/mandos/release : revision 237.7.452

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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#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 */

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#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,

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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() */

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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

free(params.data);

630

} while(false);

631

}

632

if(dhparamsfilename == NULL){

633

if(mc->dh_bits == 0){

634

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

635

/* Try to read the private key file */

636

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

637

do {

638

int secfile = open(seckeyfilename, O_RDONLY);

639

if(secfile == -1){

640

perror_plus("open");

641

break;

642

}

643

size_t buffer_capacity = 0;

644

while(true){

645

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

646

(size_t)buffer.size,

647

(size_t)buffer_capacity);

648

if(buffer_capacity == 0){

649

perror_plus("incbuffer");

650

free(buffer.data);

651

buffer.data = NULL;

652

break;

653

}

654

ssize_t bytes_read = read(secfile,

655

buffer.data + buffer.size,

656

BUFFER_SIZE);

657

/* EOF */

658

if(bytes_read == 0){

659

break;

660

}

661

/* check bytes_read for failure */

662

if(bytes_read < 0){

663

perror_plus("read");

664

free(buffer.data);

665

buffer.data = NULL;

666

break;

667

}

668

buffer.size += (unsigned int)bytes_read;

669

}

670

close(secfile);

671

} while(false);

672

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

673

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

674

if(buffer.data != NULL){

675

{

676

gnutls_openpgp_privkey_t privkey = NULL;

677

ret = gnutls_openpgp_privkey_init(&privkey);

678

if(ret != GNUTLS_E_SUCCESS){

679

fprintf_plus(stderr, "Error initializing OpenPGP key"

680

" structure: %s",

681

safer_gnutls_strerror(ret));

682

free(buffer.data);

683

buffer.data = NULL;

684

} else {

685

ret = gnutls_openpgp_privkey_import

686

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

687

if(ret != GNUTLS_E_SUCCESS){

688

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

689

safer_gnutls_strerror(ret));

690

privkey = NULL;

691

}

692

free(buffer.data);

693

buffer.data = NULL;

694

if(privkey != NULL){

695

/* Use private key to suggest an appropriate

696

sec_param */

697

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

698

gnutls_openpgp_privkey_deinit(privkey);

699

if(debug){

700

fprintf_plus(stderr, "This OpenPGP key implies using"

701

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

702

safe_string(gnutls_sec_param_get_name

703

(sec_param)));

704

}

705

}

706

}

707

}

708

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

709

/* Err on the side of caution */

710

sec_param = GNUTLS_SEC_PARAM_ULTRA;

711

if(debug){

712

fprintf_plus(stderr, "Falling back to security parameter"

713

" \"%s\"\n",

714

safe_string(gnutls_sec_param_get_name

715

(sec_param)));

716

}

717

}

718

}

719

uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

720

if(uret != 0){

721

mc->dh_bits = uret;

722

if(debug){

723

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

724

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

725

safe_string(gnutls_sec_param_get_name

726

(sec_param)),

727

mc->dh_bits);

728

}

729

} else {

730

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

731

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

732

safe_string(gnutls_sec_param_get_name

733

(sec_param)),

734

safer_gnutls_strerror(ret));

735

goto globalfail;

736

}

737

} else if(debug){

738

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

739

mc->dh_bits);

740

}

741

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

742

if(ret != GNUTLS_E_SUCCESS){

743

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

744

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

745

safer_gnutls_strerror(ret));

746

goto globalfail;

747

}

748

}

749

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

544

750

545

751

return 0;

546

752

547

753

globalfail:

548

754

549

gnutls_certificate_free_credentials(mc.cred);

550

gnutls_global_deinit();

551

gnutls_dh_params_deinit(mc.dh_params);

755

gnutls_certificate_free_credentials(mc->cred);

756

gnutls_dh_params_deinit(mc->dh_params);

552

757

return -1;

553

758

}

554

759

555

static int init_gnutls_session(gnutls_session_t *session){

760

__attribute__((nonnull, warn_unused_result))

761

static int init_gnutls_session(gnutls_session_t *session,

762

mandos_context *mc){

556

763

int ret;

557

764

/* GnuTLS session creation */

558

765

do {

570

777

{

571

778

const char *err;

572

779

do {

573

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

780

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

574

781

if(quit_now){

575

782

gnutls_deinit(*session);

576

783

return -1;

587

794

588

795

do {

589

796

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

590

mc.cred);

797

mc->cred);

591

798

if(quit_now){

592

799

gnutls_deinit(*session);

593

800

return -1;

603

810

/* ignore client certificate if any. */

604

811

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

605

812

606

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

607

608

813

return 0;

609

814

}

610

815

612

817

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

613

818

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

614

819

820

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

821

__attribute__((warn_unused_result))

822

int raise_privileges(void){

823

int old_errno = errno;

824

int ret = 0;

825

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

826

ret = errno;

827

}

828

errno = old_errno;

829

return ret;

830

}

831

832

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

833

__attribute__((warn_unused_result))

834

int raise_privileges_permanently(void){

835

int old_errno = errno;

836

int ret = raise_privileges();

837

if(ret != 0){

838

errno = old_errno;

839

return ret;

840

}

841

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

842

ret = errno;

843

}

844

errno = old_errno;

845

return ret;

846

}

847

848

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

849

__attribute__((warn_unused_result))

850

int lower_privileges(void){

851

int old_errno = errno;

852

int ret = 0;

853

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

854

ret = errno;

855

}

856

errno = old_errno;

857

return ret;

858

}

859

860

/* Lower privileges permanently */

861

__attribute__((warn_unused_result))

862

int lower_privileges_permanently(void){

863

int old_errno = errno;

864

int ret = 0;

865

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

866

ret = errno;

867

}

868

errno = old_errno;

869

return ret;

870

}

871

872

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

873

__attribute__((nonnull, warn_unused_result))

874

static bool add_delete_local_route(const bool add,

875

const char *address,

876

AvahiIfIndex if_index){

877

int ret;

878

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

879

char add_arg[] = "add";

880

char delete_arg[] = "delete";

881

char debug_flag[] = "--debug";

882

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

883

if(pluginhelperdir == NULL){

884

if(debug){

885

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

886

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

887

}

888

return false;

889

}

890

891

char interface[IF_NAMESIZE];

892

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

893

perror_plus("if_indextoname");

894

return false;

895

}

896

897

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

898

if(devnull == -1){

899

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

900

return false;

901

}

902

pid_t pid = fork();

903

if(pid == 0){

904

/* Child */

905

/* Raise privileges */

906

errno = raise_privileges_permanently();

907

if(errno != 0){

908

perror_plus("Failed to raise privileges");

909

/* _exit(EX_NOPERM); */

910

} else {

911

/* Set group */

912

errno = 0;

913

ret = setgid(0);

914

if(ret == -1){

915

perror_plus("setgid");

916

_exit(EX_NOPERM);

917

}

918

/* Reset supplementary groups */

919

errno = 0;

920

ret = setgroups(0, NULL);

921

if(ret == -1){

922

perror_plus("setgroups");

923

_exit(EX_NOPERM);

924

}

925

}

926

ret = dup2(devnull, STDIN_FILENO);

927

if(ret == -1){

928

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

929

_exit(EX_OSERR);

930

}

931

ret = close(devnull);

932

if(ret == -1){

933

perror_plus("close");

934

_exit(EX_OSERR);

935

}

936

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

937

if(ret == -1){

938

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

939

_exit(EX_OSERR);

940

}

941

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

942

O_RDONLY

943

| O_DIRECTORY

944

| O_PATH

945

| O_CLOEXEC));

946

if(helperdir_fd == -1){

947

perror_plus("open");

948

_exit(EX_UNAVAILABLE);

949

}

950

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

951

helper, O_RDONLY));

952

if(helper_fd == -1){

953

perror_plus("openat");

954

close(helperdir_fd);

955

_exit(EX_UNAVAILABLE);

956

}

957

close(helperdir_fd);

958

#ifdef __GNUC__

959

#pragma GCC diagnostic push

960

#pragma GCC diagnostic ignored "-Wcast-qual"

961

#endif

962

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

963

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

964

interface, debug ? debug_flag : NULL, NULL },

965

environ) == -1){

966

#ifdef __GNUC__

967

#pragma GCC diagnostic pop

968

#endif

969

perror_plus("fexecve");

970

_exit(EXIT_FAILURE);

971

}

972

}

973

if(pid == -1){

974

perror_plus("fork");

975

return false;

976

}

977

int status;

978

pid_t pret = -1;

979

errno = 0;

980

do {

981

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

982

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

983

int errno_raising = 0;

984

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

985

errno_raising = errno;

986

perror_plus("Failed to raise privileges in order to"

987

" kill helper program");

988

}

989

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

990

perror_plus("kill");

991

}

992

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

993

perror_plus("Failed to lower privileges after killing"

994

" helper program");

995

}

996

return false;

997

}

998

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

999

if(pret == -1){

1000

perror_plus("waitpid");

1001

return false;

1002

}

1003

if(WIFEXITED(status)){

1004

if(WEXITSTATUS(status) != 0){

1005

fprintf_plus(stderr, "Error: iprouteadddel exited"

1006

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

1007

return false;

1008

}

1009

return true;

1010

}

1011

if(WIFSIGNALED(status)){

1012

fprintf_plus(stderr, "Error: iprouteadddel died by"

1013

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

1014

return false;

1015

}

1016

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

1017

return false;

1018

}

1019

1020

__attribute__((nonnull, warn_unused_result))

1021

static bool add_local_route(const char *address,

1022

AvahiIfIndex if_index){

1023

if(debug){

1024

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

1025

}

1026

return add_delete_local_route(true, address, if_index);

1027

}

1028

1029

__attribute__((nonnull, warn_unused_result))

1030

static bool delete_local_route(const char *address,

1031

AvahiIfIndex if_index){

1032

if(debug){

1033

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

1034

}

1035

return add_delete_local_route(false, address, if_index);

1036

}

1037

615

1038

/* Called when a Mandos server is found */

616

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

1039

__attribute__((nonnull, warn_unused_result))

1040

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

617

1041

AvahiIfIndex if_index,

618

int af){

1042

int af, mandos_context *mc){

619

1043

int ret, tcp_sd = -1;

620

1044

ssize_t sret;

621

union {

622

struct sockaddr_in in;

623

struct sockaddr_in6 in6;

624

} to;

1045

struct sockaddr_storage to;

625

1046

char *buffer = NULL;

626

1047

char *decrypted_buffer = NULL;

627

1048

size_t buffer_length = 0;

630

1051

int retval = -1;

631

1052

gnutls_session_t session;

632

1053

int pf; /* Protocol family */

1054

bool route_added = false;

633

1055

634

1056

errno = 0;

635

1057

651

1073

return -1;

652

1074

}

653

1075

654

ret = init_gnutls_session(&session);

1076

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

1077

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

1078

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

1079

bool match = false;

1080

{

1081

char *interface = NULL;

1082

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

1083

mc->interfaces_size,

1084

interface))){

1085

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

1086

match = true;

1087

break;

1088

}

1089

}

1090

}

1091

if(not match){

1092

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

1093

connect to the server */

1094

if(debug){

1095

char interface[IF_NAMESIZE];

1096

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

1097

perror_plus("if_indextoname");

1098

} else {

1099

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

1100

" \"%s\"\n",

1101

if_indextoname((unsigned int)if_index,

1102

interface));

1103

}

1104

}

1105

return -1;

1106

}

1107

}

1108

1109

ret = init_gnutls_session(&session, mc);

655

1110

if(ret != 0){

656

1111

return -1;

657

1112

}

658

1113

659

1114

if(debug){

660

1115

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

661

PRIu16 "\n", ip, port);

1116

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

662

1117

}

663

1118

664

tcp_sd = socket(pf, SOCK_STREAM, 0);

1119

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

665

1120

if(tcp_sd < 0){

666

1121

int e = errno;

667

1122

perror_plus("socket");

674

1129

goto mandos_end;

675

1130

}

676

1131

677

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

678

1132

if(af == AF_INET6){

679

to.in6.sin6_family = (sa_family_t)af;

680

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

1133

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

1134

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

1135

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

681

1136

} else { /* IPv4 */

682

to.in.sin_family = (sa_family_t)af;

683

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

1137

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

1138

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

1139

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

684

1140

}

685

1141

if(ret < 0 ){

686

1142

int e = errno;

695

1151

goto mandos_end;

696

1152

}

697

1153

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*/

1154

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

1155

if(IN6_IS_ADDR_LINKLOCAL

1156

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

705

1157

if(if_index == AVAHI_IF_UNSPEC){

706

1158

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

707

1159

" incomplete without a network interface\n");

709

1161

goto mandos_end;

710

1162

}

711

1163

/* Set the network interface number as scope */

712

to.in6.sin6_scope_id = (uint32_t)if_index;

1164

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

713

1165

}

714

1166

} else {

715

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

716

-Wconversion and

717

-Wunreachable-code */

1167

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

718

1168

}

719

1169

720

1170

if(quit_now){

728

1178

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

729

1179

perror_plus("if_indextoname");

730

1180

} else {

731

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

732

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

1181

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

1182

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

733

1183

}

734

1184

} else {

735

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

736

ip, port);

1185

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

1186

ip, (uintmax_t)port);

737

1187

}

738

1188

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

739

1189

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;

1190

if(af == AF_INET6){

1191

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

1192

sizeof(struct sockaddr_in6),

1193

addrstr, sizeof(addrstr), NULL, 0,

1194

NI_NUMERICHOST);

1195

} else {

1196

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

1197

sizeof(struct sockaddr_in),

1198

addrstr, sizeof(addrstr), NULL, 0,

1199

NI_NUMERICHOST);

1200

}

1201

if(ret == EAI_SYSTEM){

1202

perror_plus("getnameinfo");

1203

} else if(ret != 0) {

1204

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

1205

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

1206

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

1207

}

1208

}

1209

1210

if(quit_now){

1211

errno = EINTR;

1212

goto mandos_end;

1213

}

1214

1215

while(true){

1216

if(af == AF_INET6){

1217

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

1218

sizeof(struct sockaddr_in6));

1219

} else {

1220

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

1221

sizeof(struct sockaddr_in));

1222

}

1223

if(ret < 0){

1224

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

1225

and if_index != AVAHI_IF_UNSPEC

1226

and connect_to == NULL

1227

and not route_added and

1228

((af == AF_INET6 and not

1229

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1230

&to)->sin6_addr)))

1231

or (af == AF_INET and

1232

/* Not a a IPv4LL address */

1233

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

1234

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

1235

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

1236

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

1237

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

1238

connect to a Mandos server announced by Avahi on a server

1239

host with a global address. Work around this by retrying

1240

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

1241

1242

Avahi bug reference:

1243

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

1244

https://bugs.debian.org/587961

1245

*/

1246

if(debug){

1247

fprintf_plus(stderr, "Mandos server unreachable, trying"

1248

" direct route\n");

1249

}

1250

int e = errno;

1251

route_added = add_local_route(ip, if_index);

1252

if(route_added){

1253

continue;

1254

}

1255

errno = e;

1256

}

1257

if(errno != ECONNREFUSED or debug){

1258

int e = errno;

1259

perror_plus("connect");

1260

errno = e;

1261

}

1262

goto mandos_end;

1263

}

1264

1265

if(quit_now){

1266

errno = EINTR;

1267

goto mandos_end;

1268

}

1269

break;

779

1270

}

780

1271

781

1272

const char *out = mandos_protocol_version;

817

1308

goto mandos_end;

818

1309

}

819

1310

820

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

821

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

1311

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

1312

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

1313

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

1314

gnutls_transport_set_ptr(session,

1315

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

822

1316

823

1317

if(quit_now){

824

1318

errno = EINTR;

929

1423

if(buffer_length > 0){

930

1424

ssize_t decrypted_buffer_size;

931

1425

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

932

&decrypted_buffer);

1426

&decrypted_buffer, mc);

933

1427

if(decrypted_buffer_size >= 0){

934

1428

1429

clearerr(stdout);

935

1430

written = 0;

936

1431

while(written < (size_t) decrypted_buffer_size){

937

1432

if(quit_now){

953

1448

}

954

1449

written += (size_t)ret;

955

1450

}

1451

ret = fflush(stdout);

1452

if(ret != 0){

1453

int e = errno;

1454

if(debug){

1455

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

1456

strerror(errno));

1457

}

1458

errno = e;

1459

goto mandos_end;

1460

}

956

1461

retval = 0;

957

1462

}

958

1463

}

961

1466

962

1467

mandos_end:

963

1468

{

1469

if(route_added){

1470

if(not delete_local_route(ip, if_index)){

1471

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

1472

" interface %d", ip, if_index);

1473

}

1474

}

964

1475

int e = errno;

965

1476

free(decrypted_buffer);

966

1477

free(buffer);

967

1478

if(tcp_sd >= 0){

968

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

1479

ret = close(tcp_sd);

969

1480

}

970

1481

if(ret == -1){

971

1482

if(e == 0){

996

1507

AVAHI_GCC_UNUSED AvahiStringList *txt,

997

1508

AVAHI_GCC_UNUSED AvahiLookupResultFlags

998

1509

flags,

999

AVAHI_GCC_UNUSED void* userdata){

1000

assert(r);

1510

void *mc){

1511

if(r == NULL){

1512

return;

1513

}

1001

1514

1002

1515

/* Called whenever a service has been resolved successfully or

1003

1516

timed out */

1004

1517

1005

1518

if(quit_now){

1519

avahi_s_service_resolver_free(r);

1006

1520

return;

1007

1521

}

1008

1522

1012

1526

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

1013

1527

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

1014

1528

domain,

1015

avahi_strerror(avahi_server_errno(mc.server)));

1529

avahi_strerror(avahi_server_errno

1530

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

1016

1531

break;

1017

1532

1018

1533

case AVAHI_RESOLVER_FOUND:

1024

1539

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

1025

1540

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

1026

1541

}

1027

int ret = start_mandos_communication(ip, port, interface,

1028

avahi_proto_to_af(proto));

1542

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

1543

interface,

1544

avahi_proto_to_af(proto),

1545

mc);

1029

1546

if(ret == 0){

1030

avahi_simple_poll_quit(mc.simple_poll);

1547

avahi_simple_poll_quit(simple_poll);

1031

1548

} else {

1032

ret = add_server(ip, port, interface,

1033

avahi_proto_to_af(proto));

1549

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

1550

avahi_proto_to_af(proto),

1551

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

1552

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

1553

" list\n", name);

1554

}

1034

1555

}

1035

1556

}

1036

1557

}

1046

1567

const char *domain,

1047

1568

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1048

1569

flags,

1049

AVAHI_GCC_UNUSED void* userdata){

1050

assert(b);

1570

void *mc){

1571

if(b == NULL){

1572

return;

1573

}

1051

1574

1052

1575

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

1053

1576

is removed from the LAN */

1061

1584

case AVAHI_BROWSER_FAILURE:

1062

1585

1063

1586

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

1064

avahi_strerror(avahi_server_errno(mc.server)));

1065

avahi_simple_poll_quit(mc.simple_poll);

1587

avahi_strerror(avahi_server_errno

1588

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

1589

avahi_simple_poll_quit(simple_poll);

1066

1590

return;

1067

1591

1068

1592

case AVAHI_BROWSER_NEW:

1071

1595

the callback function is called the Avahi server will free the

1072

1596

resolver for us. */

1073

1597

1074

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

1075

name, type, domain, protocol, 0,

1076

resolve_callback, NULL) == NULL)

1598

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

1599

interface, protocol, name, type,

1600

domain, protocol, 0,

1601

resolve_callback, mc) == NULL)

1077

1602

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

1078

1603

" %s\n", name,

1079

avahi_strerror(avahi_server_errno(mc.server)));

1604

avahi_strerror(avahi_server_errno

1605

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

1080

1606

break;

1081

1607

1082

1608

case AVAHI_BROWSER_REMOVE:

1101

1627

signal_received = sig;

1102

1628

int old_errno = errno;

1103

1629

/* set main loop to exit */

1104

if(mc.simple_poll != NULL){

1105

avahi_simple_poll_quit(mc.simple_poll);

1630

if(simple_poll != NULL){

1631

avahi_simple_poll_quit(simple_poll);

1106

1632

}

1107

1633

errno = old_errno;

1108

1634

}

1109

1635

1636

__attribute__((nonnull, warn_unused_result))

1110

1637

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

1111

1638

int ret;

1639

int old_errno;

1112

1640

1113

1641

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

1114

1642

if(s < 0){

1643

old_errno = errno;

1115

1644

perror_plus("socket");

1645

errno = old_errno;

1116

1646

return false;

1117

1647

}

1118

strcpy(ifr->ifr_name, ifname);

1648

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

1649

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

1119

1650

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1120

1651

if(ret == -1){

1121

1652

if(debug){

1653

old_errno = errno;

1122

1654

perror_plus("ioctl SIOCGIFFLAGS");

1655

errno = old_errno;

1123

1656

}

1124

1657

return false;

1125

1658

}

1126

1659

return true;

1127

1660

}

1128

1661

1662

__attribute__((nonnull, warn_unused_result))

1129

1663

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

1130

1664

1131

1665

/* Reject the loopback device */

1173

1707

* corresponds to an acceptable network device.

1174

1708

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

1175

1709

*/

1710

__attribute__((nonnull, warn_unused_result))

1176

1711

int good_interface(const struct dirent *if_entry){

1177

1712

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

1178

1713

return 0;

1194

1729

}

1195

1730

1196

1731

/*

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

1732

* This function determines if a network interface is up.

1733

*/

1734

__attribute__((nonnull, warn_unused_result))

1735

bool interface_is_up(const char *interface){

1736

struct ifreq ifr;

1737

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

1738

if(debug){

1739

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

1740

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

1741

}

1742

return false;

1743

}

1744

1745

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

1746

}

1747

1748

/*

1749

* This function determines if a network interface is running

1750

*/

1751

__attribute__((nonnull, warn_unused_result))

1752

bool interface_is_running(const char *interface){

1753

struct ifreq ifr;

1754

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

1755

if(debug){

1756

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

1757

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

1758

}

1759

return false;

1760

}

1761

1762

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

1763

}

1764

1765

__attribute__((nonnull, pure, warn_unused_result))

1239

1766

int notdotentries(const struct dirent *direntry){

1240

1767

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

1241

1768

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

1248

1775

}

1249

1776

1250

1777

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

1778

__attribute__((nonnull, warn_unused_result))

1251

1779

int runnable_hook(const struct dirent *direntry){

1252

1780

int ret;

1253

1781

size_t sret;

1261

1789

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

1262

1790

"abcdefghijklmnopqrstuvwxyz"

1263

1791

"0123456789"

1264

"_-");

1792

"_.-");

1265

1793

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

1266

1794

/* Contains non-allowed characters */

1267

1795

if(debug){

1271

1799

return 0;

1272

1800

}

1273

1801

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);

1802

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

1282

1803

if(ret == -1){

1283

1804

if(debug){

1284

1805

perror_plus("Could not stat hook");

1301

1822

}

1302

1823

return 0;

1303

1824

}

1825

if(debug){

1826

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

1827

direntry->d_name);

1828

}

1304

1829

return 1;

1305

1830

}

1306

1831

1307

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1832

__attribute__((nonnull, warn_unused_result))

1833

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1834

mandos_context *mc){

1308

1835

int ret;

1309

1836

struct timespec now;

1310

1837

struct timespec waited_time;

1311

1838

intmax_t block_time;

1312

1839

1313

1840

while(true){

1314

if(mc.current_server == NULL){

1315

if (debug){

1841

if(mc->current_server == NULL){

1842

if(debug){

1316

1843

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

1317

1844

" No timeout!\n");

1318

1845

}

1319

1846

ret = avahi_simple_poll_iterate(s, -1);

1320

1847

} else {

1321

if (debug){

1848

if(debug){

1322

1849

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

1323

1850

" it, or wait\n");

1324

1851

}

1331

1858

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

1332

1859

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

1333

1860

waited_time.tv_sec = (now.tv_sec

1334

- mc.current_server->last_seen.tv_sec);

1861

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

1335

1862

waited_time.tv_nsec = (now.tv_nsec

1336

- mc.current_server->last_seen.tv_nsec);

1863

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

1337

1864

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

1338

1865

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

1339

1866

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

1341

1868

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

1342

1869

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

1343

1870

1344

if (debug){

1871

if(debug){

1345

1872

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

1346

1873

block_time);

1347

1874

}

1348

1875

1349

1876

if(block_time <= 0){

1350

ret = start_mandos_communication(mc.current_server->ip,

1351

mc.current_server->port,

1352

mc.current_server->if_index,

1353

mc.current_server->af);

1877

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

1878

mc->current_server->port,

1879

mc->current_server->if_index,

1880

mc->current_server->af, mc);

1354

1881

if(ret == 0){

1355

avahi_simple_poll_quit(mc.simple_poll);

1882

avahi_simple_poll_quit(s);

1356

1883

return 0;

1357

1884

}

1358

1885

ret = clock_gettime(CLOCK_MONOTONIC,

1359

&mc.current_server->last_seen);

1886

&mc->current_server->last_seen);

1360

1887

if(ret == -1){

1361

1888

perror_plus("clock_gettime");

1362

1889

return -1;

1363

1890

}

1364

mc.current_server = mc.current_server->next;

1891

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

1365

1892

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

1366

1893

servers, but don't block */

1367

1894

}

1369

1896

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

1370

1897

}

1371

1898

if(ret != 0){

1372

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

1899

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

1373

1900

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

1374

1901

}

1375

1902

}

1376

1903

}

1377

1904

}

1378

1905

1379

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

1906

__attribute__((nonnull))

1907

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

1380

1908

const float delay){

1381

struct dirent **direntries;

1382

struct dirent *direntry;

1383

int ret;

1384

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

1385

alphasort);

1909

struct dirent **direntries = NULL;

1910

if(hookdir_fd == -1){

1911

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

1912

| O_CLOEXEC);

1913

if(hookdir_fd == -1){

1914

if(errno == ENOENT){

1915

if(debug){

1916

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

1917

" found\n", hookdir);

1918

}

1919

} else {

1920

perror_plus("open");

1921

}

1922

return;

1923

}

1924

}

1925

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

1926

runnable_hook, alphasort);

1386

1927

if(numhooks == -1){

1387

1928

perror_plus("scandir");

1388

} else {

1389

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

1390

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

1391

direntry = direntries[0];

1392

char *fullname = NULL;

1393

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

1394

if(ret < 0){

1929

return;

1930

}

1931

struct dirent *direntry;

1932

int ret;

1933

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

1934

if(devnull == -1){

1935

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

1936

return;

1937

}

1938

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

1939

direntry = direntries[i];

1940

if(debug){

1941

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

1942

direntry->d_name);

1943

}

1944

pid_t hook_pid = fork();

1945

if(hook_pid == 0){

1946

/* Child */

1947

/* Raise privileges */

1948

errno = raise_privileges_permanently();

1949

if(errno != 0){

1950

perror_plus("Failed to raise privileges");

1951

_exit(EX_NOPERM);

1952

}

1953

/* Set group */

1954

errno = 0;

1955

ret = setgid(0);

1956

if(ret == -1){

1957

perror_plus("setgid");

1958

_exit(EX_NOPERM);

1959

}

1960

/* Reset supplementary groups */

1961

errno = 0;

1962

ret = setgroups(0, NULL);

1963

if(ret == -1){

1964

perror_plus("setgroups");

1965

_exit(EX_NOPERM);

1966

}

1967

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

1968

if(ret == -1){

1969

perror_plus("setenv");

1970

_exit(EX_OSERR);

1971

}

1972

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

1973

if(ret == -1){

1974

perror_plus("setenv");

1975

_exit(EX_OSERR);

1976

}

1977

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

1978

if(ret == -1){

1979

perror_plus("setenv");

1980

_exit(EX_OSERR);

1981

}

1982

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

1983

if(ret == -1){

1984

perror_plus("setenv");

1985

_exit(EX_OSERR);

1986

}

1987

char *delaystring;

1988

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

1989

if(ret == -1){

1395

1990

perror_plus("asprintf");

1396

continue;

1991

_exit(EX_OSERR);

1397

1992

}

1398

pid_t hook_pid = fork();

1399

if(hook_pid == 0){

1400

/* Child */

1401

dup2(devnull, STDIN_FILENO);

1402

close(devnull);

1403

dup2(STDERR_FILENO, STDOUT_FILENO);

1404

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

1405

if(ret == -1){

1406

perror_plus("setenv");

1407

return false;

1408

}

1409

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

1410

if(ret == -1){

1411

perror_plus("setenv");

1412

return false;

1413

}

1414

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

1415

if(ret == -1){

1416

perror_plus("setenv");

1417

return false;

1418

}

1419

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

1420

if(ret == -1){

1421

perror_plus("setenv");

1422

return false;

1423

}

1424

char *delaystring;

1425

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

1426

if(ret == -1){

1427

perror_plus("asprintf");

1428

return false;

1429

}

1430

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

1431

if(ret == -1){

1432

free(delaystring);

1433

perror_plus("setenv");

1434

return false;

1435

}

1993

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

1994

if(ret == -1){

1436

1995

free(delaystring);

1437

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

1438

perror_plus("execl");

1439

} else {

1440

int status;

1441

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

1442

perror_plus("waitpid");

1443

free(fullname);

1444

continue;

1445

}

1446

if(WIFEXITED(status)){

1447

if(WEXITSTATUS(status) != 0){

1448

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

1449

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

1450

WEXITSTATUS(status));

1451

free(fullname);

1452

continue;

1453

}

1454

} else if(WIFSIGNALED(status)){

1455

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

1456

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

1457

WTERMSIG(status));

1458

free(fullname);

1459

continue;

1460

} else {

1461

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

1462

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

1463

free(fullname);

1464

continue;

1465

}

1466

}

1467

free(fullname);

1468

if(quit_now){

1469

break;

1470

}

1471

}

1472

close(devnull);

1473

}

1474

return true;

1996

perror_plus("setenv");

1997

_exit(EX_OSERR);

1998

}

1999

free(delaystring);

2000

if(connect_to != NULL){

2001

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

2002

if(ret == -1){

2003

perror_plus("setenv");

2004

_exit(EX_OSERR);

2005

}

2006

}

2007

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

2008

direntry->d_name,

2009

O_RDONLY));

2010

if(hook_fd == -1){

2011

perror_plus("openat");

2012

_exit(EXIT_FAILURE);

2013

}

2014

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

2015

perror_plus("close");

2016

_exit(EXIT_FAILURE);

2017

}

2018

ret = dup2(devnull, STDIN_FILENO);

2019

if(ret == -1){

2020

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

2021

_exit(EX_OSERR);

2022

}

2023

ret = close(devnull);

2024

if(ret == -1){

2025

perror_plus("close");

2026

_exit(EX_OSERR);

2027

}

2028

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

2029

if(ret == -1){

2030

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

2031

_exit(EX_OSERR);

2032

}

2033

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

2034

environ) == -1){

2035

perror_plus("fexecve");

2036

_exit(EXIT_FAILURE);

2037

}

2038

} else {

2039

if(hook_pid == -1){

2040

perror_plus("fork");

2041

free(direntry);

2042

continue;

2043

}

2044

int status;

2045

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

2046

perror_plus("waitpid");

2047

free(direntry);

2048

continue;

2049

}

2050

if(WIFEXITED(status)){

2051

if(WEXITSTATUS(status) != 0){

2052

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

2053

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

2054

WEXITSTATUS(status));

2055

free(direntry);

2056

continue;

2057

}

2058

} else if(WIFSIGNALED(status)){

2059

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

2060

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

2061

WTERMSIG(status));

2062

free(direntry);

2063

continue;

2064

} else {

2065

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

2066

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

2067

free(direntry);

2068

continue;

2069

}

2070

}

2071

if(debug){

2072

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

2073

direntry->d_name);

2074

}

2075

free(direntry);

2076

}

2077

free(direntries);

2078

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

2079

perror_plus("close");

2080

} else {

2081

hookdir_fd = -1;

2082

}

2083

close(devnull);

2084

}

2085

2086

__attribute__((nonnull, warn_unused_result))

2087

int bring_up_interface(const char *const interface,

2088

const float delay){

2089

int old_errno = errno;

2090

int ret;

2091

struct ifreq network;

2092

unsigned int if_index = if_nametoindex(interface);

2093

if(if_index == 0){

2094

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

2095

errno = old_errno;

2096

return ENXIO;

2097

}

2098

2099

if(quit_now){

2100

errno = old_errno;

2101

return EINTR;

2102

}

2103

2104

if(not interface_is_up(interface)){

2105

int ret_errno = 0;

2106

int ioctl_errno = 0;

2107

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

2108

ret_errno = errno;

2109

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

2110

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

2111

errno = old_errno;

2112

return ret_errno;

2113

}

2114

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

2115

2116

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

2117

if(sd == -1){

2118

ret_errno = errno;

2119

perror_plus("socket");

2120

errno = old_errno;

2121

return ret_errno;

2122

}

2123

2124

if(quit_now){

2125

ret = close(sd);

2126

if(ret == -1){

2127

perror_plus("close");

2128

}

2129

errno = old_errno;

2130

return EINTR;

2131

}

2132

2133

if(debug){

2134

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

2135

interface);

2136

}

2137

2138

/* Raise privileges */

2139

ret_errno = raise_privileges();

2140

if(ret_errno != 0){

2141

errno = ret_errno;

2142

perror_plus("Failed to raise privileges");

2143

}

2144

2145

#ifdef __linux__

2146

int ret_linux;

2147

bool restore_loglevel = false;

2148

if(ret_errno == 0){

2149

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

2150

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

2151

ret_linux = klogctl(8, NULL, 5);

2152

if(ret_linux == -1){

2153

perror_plus("klogctl");

2154

} else {

2155

restore_loglevel = true;

2156

}

2157

}

2158

#endif /* __linux__ */

2159

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

2160

ioctl_errno = errno;

2161

#ifdef __linux__

2162

if(restore_loglevel){

2163

ret_linux = klogctl(7, NULL, 0);

2164

if(ret_linux == -1){

2165

perror_plus("klogctl");

2166

}

2167

}

2168

#endif /* __linux__ */

2169

2170

/* If raise_privileges() succeeded above */

2171

if(ret_errno == 0){

2172

/* Lower privileges */

2173

ret_errno = lower_privileges();

2174

if(ret_errno != 0){

2175

errno = ret_errno;

2176

perror_plus("Failed to lower privileges");

2177

}

2178

}

2179

2180

/* Close the socket */

2181

ret = close(sd);

2182

if(ret == -1){

2183

perror_plus("close");

2184

}

2185

2186

if(ret_setflags == -1){

2187

errno = ioctl_errno;

2188

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

2189

errno = old_errno;

2190

return ioctl_errno;

2191

}

2192

} else if(debug){

2193

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

2194

interface);

2195

}

2196

2197

/* Sleep checking until interface is running.

2198

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

2199

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

2200

if(interface_is_running(interface)){

2201

break;

2202

}

2203

struct timespec sleeptime = { .tv_nsec = 250000000 };

2204

ret = nanosleep(&sleeptime, NULL);

2205

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

2206

perror_plus("nanosleep");

2207

}

2208

}

2209

2210

errno = old_errno;

2211

return 0;

2212

}

2213

2214

__attribute__((nonnull, warn_unused_result))

2215

int take_down_interface(const char *const interface){

2216

int old_errno = errno;

2217

struct ifreq network;

2218

unsigned int if_index = if_nametoindex(interface);

2219

if(if_index == 0){

2220

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

2221

errno = old_errno;

2222

return ENXIO;

2223

}

2224

if(interface_is_up(interface)){

2225

int ret_errno = 0;

2226

int ioctl_errno = 0;

2227

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

2228

ret_errno = errno;

2229

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

2230

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

2231

errno = old_errno;

2232

return ret_errno;

2233

}

2234

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

2235

2236

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

2237

if(sd == -1){

2238

ret_errno = errno;

2239

perror_plus("socket");

2240

errno = old_errno;

2241

return ret_errno;

2242

}

2243

2244

if(debug){

2245

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

2246

interface);

2247

}

2248

2249

/* Raise privileges */

2250

ret_errno = raise_privileges();

2251

if(ret_errno != 0){

2252

errno = ret_errno;

2253

perror_plus("Failed to raise privileges");

2254

}

2255

2256

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

2257

ioctl_errno = errno;

2258

2259

/* If raise_privileges() succeeded above */

2260

if(ret_errno == 0){

2261

/* Lower privileges */

2262

ret_errno = lower_privileges();

2263

if(ret_errno != 0){

2264

errno = ret_errno;

2265

perror_plus("Failed to lower privileges");

2266

}

2267

}

2268

2269

/* Close the socket */

2270

int ret = close(sd);

2271

if(ret == -1){

2272

perror_plus("close");

2273

}

2274

2275

if(ret_setflags == -1){

2276

errno = ioctl_errno;

2277

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2278

errno = old_errno;

2279

return ioctl_errno;

2280

}

2281

} else if(debug){

2282

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

2283

interface);

2284

}

2285

2286

errno = old_errno;

2287

return 0;

1475

2288

}

1476

2289

1477

2290

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

2291

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

2292

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

2293

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

2294

.current_server = NULL, .interfaces = NULL,

2295

.interfaces_size = 0 };

1478

2296

AvahiSServiceBrowser *sb = NULL;

1479

int error;

2297

error_t ret_errno;

1480

2298

int ret;

1481

2299

intmax_t tmpmax;

1482

2300

char *tmp;

1483

2301

int exitcode = EXIT_SUCCESS;

1484

const char *interface = "";

1485

struct ifreq network;

1486

int sd = -1;

1487

bool take_down_interface = false;

1488

uid_t uid;

1489

gid_t gid;

1490

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

1491

bool tempdir_created = false;

2302

char *interfaces_to_take_down = NULL;

2303

size_t interfaces_to_take_down_size = 0;

2304

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

2305

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

2306

char *tempdir = NULL;

1492

2307

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1493

2308

const char *seckey = PATHDIR "/" SECKEY;

1494

2309

const char *pubkey = PATHDIR "/" PUBKEY;

2310

const char *dh_params_file = NULL;

2311

char *interfaces_hooks = NULL;

1495

2312

1496

2313

bool gnutls_initialized = false;

1497

2314

bool gpgme_initialized = false;

1549

2366

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

1550

2367

" Diffie-Hellman key exchange",

1551

2368

.group = 2 },

2369

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

2370

.arg = "FILE",

2371

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

2372

" for the Diffie-Hellman key exchange",

2373

.group = 2 },

1552

2374

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

1553

2375

.arg = "STRING",

1554

2376

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

1559

2381

.group = 2 },

1560

2382

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

1561

2383

.arg = "SECONDS",

1562

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

2384

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

1563

2385

.group = 2 },

1564

2386

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

1565

2387

.arg = "DIR",

1588

2410

connect_to = arg;

1589

2411

break;

1590

2412

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

1591

interface = arg;

2413

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

2414

arg, (int)',');

2415

if(ret_errno != 0){

2416

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

2417

}

1592

2418

break;

1593

2419

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

1594

2420

seckey = arg;

1605

2431

}

1606

2432

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

1607

2433

break;

2434

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

2435

dh_params_file = arg;

2436

break;

1608

2437

case 130: /* --priority */

1609

2438

mc.priority = arg;

1610

2439

break;

1637

2466

argp_state_help(state, state->out_stream,

1638

2467

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1639

2468

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

1640

fprintf_plus(state->out_stream,

1641

"Mandos plugin mandos-client: ");

1642

2469

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

1643

2470

exit(argp_err_exit_status);

1644

2471

break;

1652

2479

.args_doc = "",

1653

2480

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

1654

2481

" passwords from a Mandos server" };

1655

ret = argp_parse(&argp, argc, argv,

1656

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1657

switch(ret){

2482

ret_errno = argp_parse(&argp, argc, argv,

2483

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2484

switch(ret_errno){

1658

2485

case 0:

1659

2486

break;

1660

2487

case ENOMEM:

1661

2488

default:

1662

errno = ret;

2489

errno = ret_errno;

1663

2490

perror_plus("argp_parse");

1664

2491

exitcode = EX_OSERR;

1665

2492

goto end;

1668

2495

goto end;

1669

2496

}

1670

2497

}

1671

2498

1672

2499

{

1673

2500

/* Work around Debian bug #633582:

1674

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

1675

struct stat st;

1676

1677

/* Re-raise priviliges */

1678

errno = 0;

1679

ret = seteuid(0);

1680

if(ret == -1){

1681

perror_plus("seteuid");

1682

}

1683

1684

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

1685

int seckey_fd = open(seckey, O_RDONLY);

1686

if(seckey_fd == -1){

1687

perror_plus("open");

1688

} else {

1689

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

1690

if(ret == -1){

1691

perror_plus("fstat");

1692

} else {

1693

if(S_ISREG(st.st_mode)

1694

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

1695

ret = fchown(seckey_fd, uid, gid);

1696

if(ret == -1){

1697

perror_plus("fchown");

1698

}

1699

}

1700

}

1701

TEMP_FAILURE_RETRY(close(seckey_fd));

1702

}

1703

}

1704

1705

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

1706

int pubkey_fd = open(pubkey, O_RDONLY);

1707

if(pubkey_fd == -1){

1708

perror_plus("open");

1709

} else {

1710

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

1711

if(ret == -1){

1712

perror_plus("fstat");

1713

} else {

1714

if(S_ISREG(st.st_mode)

1715

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

1716

ret = fchown(pubkey_fd, uid, gid);

1717

if(ret == -1){

1718

perror_plus("fchown");

1719

}

1720

}

1721

}

1722

TEMP_FAILURE_RETRY(close(pubkey_fd));

1723

}

1724

}

1725

1726

/* Lower privileges */

1727

errno = 0;

1728

ret = seteuid(uid);

1729

if(ret == -1){

1730

perror_plus("seteuid");

2501

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

2502

2503

/* Re-raise privileges */

2504

ret = raise_privileges();

2505

if(ret != 0){

2506

errno = ret;

2507

perror_plus("Failed to raise privileges");

2508

} else {

2509

struct stat st;

2510

2511

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

2512

int seckey_fd = open(seckey, O_RDONLY);

2513

if(seckey_fd == -1){

2514

perror_plus("open");

2515

} else {

2516

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

2517

if(ret == -1){

2518

perror_plus("fstat");

2519

} else {

2520

if(S_ISREG(st.st_mode)

2521

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

2522

ret = fchown(seckey_fd, uid, gid);

2523

if(ret == -1){

2524

perror_plus("fchown");

2525

}

2526

}

2527

}

2528

close(seckey_fd);

2529

}

2530

}

2531

2532

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

2533

int pubkey_fd = open(pubkey, O_RDONLY);

2534

if(pubkey_fd == -1){

2535

perror_plus("open");

2536

} else {

2537

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

2538

if(ret == -1){

2539

perror_plus("fstat");

2540

} else {

2541

if(S_ISREG(st.st_mode)

2542

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

2543

ret = fchown(pubkey_fd, uid, gid);

2544

if(ret == -1){

2545

perror_plus("fchown");

2546

}

2547

}

2548

}

2549

close(pubkey_fd);

2550

}

2551

}

2552

2553

if(dh_params_file != NULL

2554

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

2555

int dhparams_fd = open(dh_params_file, O_RDONLY);

2556

if(dhparams_fd == -1){

2557

perror_plus("open");

2558

} else {

2559

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

2560

if(ret == -1){

2561

perror_plus("fstat");

2562

} else {

2563

if(S_ISREG(st.st_mode)

2564

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

2565

ret = fchown(dhparams_fd, uid, gid);

2566

if(ret == -1){

2567

perror_plus("fchown");

2568

}

2569

}

2570

}

2571

close(dhparams_fd);

2572

}

2573

}

2574

2575

/* Lower privileges */

2576

ret = lower_privileges();

2577

if(ret != 0){

2578

errno = ret;

2579

perror_plus("Failed to lower privileges");

2580

}

2581

}

2582

}

2583

2584

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

2585

{

2586

char *interface = NULL;

2587

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

2588

interface))){

2589

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

2590

and if_nametoindex(interface) == 0){

2591

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

2592

fprintf_plus(stderr, "Not using nonexisting interface"

2593

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

2594

}

2595

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

2596

interface = NULL;

2597

}

1731

2598

}

1732

2599

}

1733

2600

1734

2601

/* Run network hooks */

1735

2602

{

1736

/* Re-raise priviliges */

1737

errno = 0;

1738

ret = seteuid(0);

1739

if(ret == -1){

1740

perror_plus("seteuid");

1741

}

1742

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

1743

goto end;

1744

}

1745

/* Lower privileges */

1746

errno = 0;

1747

ret = seteuid(uid);

1748

if(ret == -1){

1749

perror_plus("seteuid");

1750

}

2603

if(mc.interfaces != NULL){

2604

interfaces_hooks = malloc(mc.interfaces_size);

2605

if(interfaces_hooks == NULL){

2606

perror_plus("malloc");

2607

goto end;

2608

}

2609

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

2610

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

2611

}

2612

run_network_hooks("start", interfaces_hooks != NULL ?

2613

interfaces_hooks : "", delay);

1751

2614

}

1752

2615

1753

2616

if(not debug){

1754

2617

avahi_set_log_function(empty_log);

1755

2618

}

1756

2619

1757

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

1758

struct dirent **direntries;

1759

/* First look for interfaces that are up */

1760

ret = scandir(sys_class_net, &direntries, up_interface,

1761

alphasort);

1762

if(ret == 0){

1763

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

1764

free(direntries);

1765

ret = scandir(sys_class_net, &direntries, good_interface,

1766

alphasort);

1767

}

1768

if(ret >= 1){

1769

/* Pick the first interface returned */

1770

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

1771

if(debug){

1772

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

1773

}

1774

if(interface == NULL){

1775

perror_plus("malloc");

1776

free(direntries);

1777

exitcode = EXIT_FAILURE;

1778

goto end;

1779

}

1780

free(direntries);

1781

} else {

1782

free(direntries);

1783

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

1784

exitcode = EXIT_FAILURE;

1785

goto end;

1786

}

1787

}

1788

1789

2620

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

1790

2621

from the signal handler */

1791

2622

/* Initialize the pseudo-RNG for Avahi */

1792

2623

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

1793

mc.simple_poll = avahi_simple_poll_new();

1794

if(mc.simple_poll == NULL){

2624

simple_poll = avahi_simple_poll_new();

2625

if(simple_poll == NULL){

1795

2626

fprintf_plus(stderr,

1796

2627

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

1797

2628

exitcode = EX_UNAVAILABLE;

1861

2692

}

1862

2693

}

1863

2694

1864

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

1865

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

1866

if_index = (AvahiIfIndex) if_nametoindex(interface);

1867

if(if_index == 0){

1868

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

1869

exitcode = EX_UNAVAILABLE;

1870

goto end;

1871

}

1872

1873

if(quit_now){

1874

goto end;

1875

}

1876

1877

/* Re-raise priviliges */

1878

errno = 0;

1879

ret = seteuid(0);

1880

if(ret == -1){

1881

perror_plus("seteuid");

1882

}

1883

1884

#ifdef __linux__

1885

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1886

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

1887

ret = klogctl(8, NULL, 5);

1888

bool restore_loglevel = true;

1889

if(ret == -1){

1890

restore_loglevel = false;

1891

perror_plus("klogctl");

1892

}

1893

#endif /* __linux__ */

1894

1895

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1896

if(sd < 0){

1897

perror_plus("socket");

1898

exitcode = EX_OSERR;

1899

#ifdef __linux__

1900

if(restore_loglevel){

1901

ret = klogctl(7, NULL, 0);

1902

if(ret == -1){

1903

perror_plus("klogctl");

1904

}

1905

}

1906

#endif /* __linux__ */

1907

/* Lower privileges */

1908

errno = 0;

1909

ret = seteuid(uid);

1910

if(ret == -1){

1911

perror_plus("seteuid");

1912

}

1913

goto end;

1914

}

1915

strcpy(network.ifr_name, interface);

1916

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

1917

if(ret == -1){

1918

perror_plus("ioctl SIOCGIFFLAGS");

1919

#ifdef __linux__

1920

if(restore_loglevel){

1921

ret = klogctl(7, NULL, 0);

1922

if(ret == -1){

1923

perror_plus("klogctl");

1924

}

1925

}

1926

#endif /* __linux__ */

1927

exitcode = EX_OSERR;

1928

/* Lower privileges */

1929

errno = 0;

1930

ret = seteuid(uid);

1931

if(ret == -1){

1932

perror_plus("seteuid");

1933

}

1934

goto end;

1935

}

1936

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

1937

network.ifr_flags |= IFF_UP;

1938

take_down_interface = true;

1939

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

1940

if(ret == -1){

1941

take_down_interface = false;

1942

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1943

exitcode = EX_OSERR;

1944

#ifdef __linux__

1945

if(restore_loglevel){

1946

ret = klogctl(7, NULL, 0);

1947

if(ret == -1){

1948

perror_plus("klogctl");

2695

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

2696

if(mc.interfaces == NULL){

2697

struct dirent **direntries = NULL;

2698

/* Look for any good interfaces */

2699

ret = scandir(sys_class_net, &direntries, good_interface,

2700

alphasort);

2701

if(ret >= 1){

2702

/* Add all found interfaces to interfaces list */

2703

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

2704

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

2705

direntries[i]->d_name);

2706

if(ret_errno != 0){

2707

errno = ret_errno;

2708

perror_plus("argz_add");

2709

free(direntries[i]);

2710

continue;

2711

}

2712

if(debug){

2713

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

2714

direntries[i]->d_name);

2715

}

2716

free(direntries[i]);

2717

}

2718

free(direntries);

2719

} else {

2720

if(ret == 0){

2721

free(direntries);

2722

}

2723

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

2724

exitcode = EXIT_FAILURE;

2725

goto end;

2726

}

2727

}

2728

2729

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

2730

{

2731

char *interface = NULL;

2732

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

2733

interface))){

2734

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

2735

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

2736

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

2737

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

2738

interface);

2739

interface = NULL;

2740

while((interface = argz_next(mc.interfaces,

2741

mc.interfaces_size, interface))){

2742

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

2743

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

2744

interface);

2745

interface = NULL;

1949

2746

}

1950

2747

}

1951

#endif /* __linux__ */

1952

/* Lower privileges */

1953

errno = 0;

1954

ret = seteuid(uid);

1955

if(ret == -1){

1956

perror_plus("seteuid");

1957

}

1958

goto end;

1959

}

1960

}

1961

/* Sleep checking until interface is running.

1962

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

1963

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

1964

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

1965

if(ret == -1){

1966

perror_plus("ioctl SIOCGIFFLAGS");

1967

} else if(network.ifr_flags & IFF_RUNNING){

1968

2748

break;

1969

2749

}

1970

struct timespec sleeptime = { .tv_nsec = 250000000 };

1971

ret = nanosleep(&sleeptime, NULL);

1972

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

1973

perror_plus("nanosleep");

1974

}

1975

}

1976

if(not take_down_interface){

1977

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

1978

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

1979

if(ret == -1){

1980

perror_plus("close");

1981

}

1982

}

1983

#ifdef __linux__

1984

if(restore_loglevel){

1985

/* Restores kernel loglevel to default */

1986

ret = klogctl(7, NULL, 0);

1987

if(ret == -1){

1988

perror_plus("klogctl");

1989

}

1990

}

1991

#endif /* __linux__ */

1992

/* Lower privileges */

1993

errno = 0;

1994

/* Lower privileges */

1995

ret = seteuid(uid);

1996

if(ret == -1){

1997

perror_plus("seteuid");

1998

}

2750

bool interface_was_up = interface_is_up(interface);

2751

errno = bring_up_interface(interface, delay);

2752

if(not interface_was_up){

2753

if(errno != 0){

2754

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

2755

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

2756

} else {

2757

errno = argz_add(&interfaces_to_take_down,

2758

&interfaces_to_take_down_size,

2759

interface);

2760

if(errno != 0){

2761

perror_plus("argz_add");

2762

}

2763

}

2764

}

2765

}

2766

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

2767

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

2768

}

2769

}

2770

2771

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

2772

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

2773

if(debug){

2774

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

2775

mc.interfaces);

2776

}

2777

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

1999

2778

}

2000

2779

2001

2780

if(quit_now){

2002

2781

goto end;

2003

2782

}

2004

2783

2005

ret = init_gnutls_global(pubkey, seckey);

2784

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

2006

2785

if(ret == -1){

2007

2786

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

2008

2787

exitcode = EX_UNAVAILABLE;

2015

2794

goto end;

2016

2795

}

2017

2796

2018

if(mkdtemp(tempdir) == NULL){

2797

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

2798

tempdir = mkdtemp(run_tempdir);

2799

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

2800

if(debug){

2801

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

2802

run_tempdir, old_tempdir);

2803

}

2804

tempdir = mkdtemp(old_tempdir);

2805

}

2806

if(tempdir == NULL){

2019

2807

perror_plus("mkdtemp");

2020

2808

goto end;

2021

2809

}

2022

tempdir_created = true;

2023

2810

2024

2811

if(quit_now){

2025

2812

goto end;

2026

2813

}

2027

2814

2028

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

2815

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

2029

2816

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

2030

2817

exitcode = EX_UNAVAILABLE;

2031

2818

goto end;

2041

2828

/* Connect directly, do not use Zeroconf */

2042

2829

/* (Mainly meant for debugging) */

2043

2830

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

2831

2044

2832

if(address == NULL){

2045

2833

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

2046

2834

exitcode = EX_USAGE;

2051

2839

goto end;

2052

2840

}

2053

2841

2054

uint16_t port;

2842

in_port_t port;

2055

2843

errno = 0;

2056

2844

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

2057

2845

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

2058

or tmpmax != (uint16_t)tmpmax){

2846

or tmpmax != (in_port_t)tmpmax){

2059

2847

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

2060

2848

exitcode = EX_USAGE;

2061

2849

goto end;

2062

2850

}

2063

2851

2064

2852

if(quit_now){

2065

2853

goto end;

2066

2854

}

2067

2855

2068

port = (uint16_t)tmpmax;

2856

port = (in_port_t)tmpmax;

2069

2857

*address = '\0';

2070

2858

/* Colon in address indicates IPv6 */

2071

2859

int af;

2087

2875

}

2088

2876

2089

2877

while(not quit_now){

2090

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

2878

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

2879

&mc);

2091

2880

if(quit_now or ret == 0){

2092

2881

break;

2093

2882

}

2095

2884

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

2096

2885

(int)retry_interval);

2097

2886

}

2098

sleep((int)retry_interval);

2887

sleep((unsigned int)retry_interval);

2099

2888

}

2100

2889

2101

if (not quit_now){

2890

if(not quit_now){

2102

2891

exitcode = EXIT_SUCCESS;

2103

2892

}

2104

2893

2119

2908

config.publish_domain = 0;

2120

2909

2121

2910

/* Allocate a new server */

2122

mc.server = avahi_server_new(avahi_simple_poll_get

2123

(mc.simple_poll), &config, NULL,

2124

NULL, &error);

2911

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2912

&config, NULL, NULL, &ret);

2125

2913

2126

2914

/* Free the Avahi configuration data */

2127

2915

avahi_server_config_free(&config);

2130

2918

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

2131

2919

if(mc.server == NULL){

2132

2920

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

2133

avahi_strerror(error));

2921

avahi_strerror(ret));

2134

2922

exitcode = EX_UNAVAILABLE;

2135

2923

goto end;

2136

2924

}

2142

2930

/* Create the Avahi service browser */

2143

2931

sb = avahi_s_service_browser_new(mc.server, if_index,

2144

2932

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2145

NULL, 0, browse_callback, NULL);

2933

NULL, 0, browse_callback,

2934

(void *)&mc);

2146

2935

if(sb == NULL){

2147

2936

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

2148

2937

avahi_strerror(avahi_server_errno(mc.server)));

2159

2948

if(debug){

2160

2949

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

2161

2950

}

2162

2163

ret = avahi_loop_with_timeout(mc.simple_poll,

2164

(int)(retry_interval * 1000));

2951

2952

ret = avahi_loop_with_timeout(simple_poll,

2953

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

2165

2954

if(debug){

2166

2955

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

2167

2956

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

2170

2959

end:

2171

2960

2172

2961

if(debug){

2173

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

2962

if(signal_received){

2963

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

2964

argv[0], signal_received,

2965

strsignal(signal_received));

2966

} else {

2967

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

2968

}

2174

2969

}

2175

2970

2176

2971

/* Cleanup things */

2972

free(mc.interfaces);

2973

2177

2974

if(sb != NULL)

2178

2975

avahi_s_service_browser_free(sb);

2179

2976

2180

2977

if(mc.server != NULL)

2181

2978

avahi_server_free(mc.server);

2182

2979

2183

if(mc.simple_poll != NULL)

2184

avahi_simple_poll_free(mc.simple_poll);

2980

if(simple_poll != NULL)

2981

avahi_simple_poll_free(simple_poll);

2185

2982

2186

2983

if(gnutls_initialized){

2187

2984

gnutls_certificate_free_credentials(mc.cred);

2188

gnutls_global_deinit();

2189

2985

gnutls_dh_params_deinit(mc.dh_params);

2190

2986

}

2191

2987

2192

2988

if(gpgme_initialized){

2193

2989

gpgme_release(mc.ctx);

2194

2990

}

2195

2991

2196

2992

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

2197

2993

has seen */

2198

2994

if(mc.current_server != NULL){

2199

2995

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

2200

2996

while(mc.current_server != NULL){

2201

2997

server *next = mc.current_server->next;

2998

#ifdef __GNUC__

2999

#pragma GCC diagnostic push

3000

#pragma GCC diagnostic ignored "-Wcast-qual"

3001

#endif

3002

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

3003

#ifdef __GNUC__

3004

#pragma GCC diagnostic pop

3005

#endif

2202

3006

free(mc.current_server);

2203

3007

mc.current_server = next;

2204

3008

}

2205

3009

}

2206

3010

2207

/* Re-raise priviliges */

3011

/* Re-raise privileges */

2208

3012

{

2209

errno = 0;

2210

ret = seteuid(0);

2211

if(ret == -1){

2212

perror_plus("seteuid");

2213

}

2214

/* Run network hooks */

2215

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

2216

goto end;

3013

ret = raise_privileges();

3014

if(ret != 0){

3015

errno = ret;

3016

perror_plus("Failed to raise privileges");

3017

} else {

3018

3019

/* Run network hooks */

3020

run_network_hooks("stop", interfaces_hooks != NULL ?

3021

interfaces_hooks : "", delay);

3022

3023

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

3024

{

3025

char *interface = NULL;

3026

while((interface = argz_next(interfaces_to_take_down,

3027

interfaces_to_take_down_size,

3028

interface))){

3029

ret = take_down_interface(interface);

3030

if(ret != 0){

3031

errno = ret;

3032

perror_plus("Failed to take down interface");

3033

}

3034

}

3035

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

3036

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

3037

" down\n");

3038

}

3039

}

2217

3040

}

2218

3041

2219

/* Take down the network interface */

2220

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

2221

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

2222

if(ret == -1){

2223

perror_plus("ioctl SIOCGIFFLAGS");

2224

} else if(network.ifr_flags & IFF_UP){

2225

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

2226

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

2227

if(ret == -1){

2228

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2229

}

2230

}

2231

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

2232

if(ret == -1){

2233

perror_plus("close");

2234

}

3042

ret = lower_privileges_permanently();

3043

if(ret != 0){

3044

errno = ret;

3045

perror_plus("Failed to lower privileges permanently");

2235

3046

}

2236

3047

}

2237

/* Lower privileges permanently */

2238

errno = 0;

2239

ret = setuid(uid);

2240

if(ret == -1){

2241

perror_plus("setuid");

3048

3049

free(interfaces_to_take_down);

3050

free(interfaces_hooks);

3051

3052

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

3053

uintmax_t level){

3054

struct dirent **direntries = NULL;

3055

int dret;

3056

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

3057

O_RDONLY

3058

| O_NOFOLLOW

3059

| O_DIRECTORY

3060

| O_PATH));

3061

if(dir_fd == -1){

3062

perror_plus("open");

3063

}

3064

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

3065

notdotentries, alphasort);

3066

if(numentries >= 0){

3067

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

3068

if(debug){

3069

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

3070

dirname, direntries[i]->d_name);

3071

}

3072

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

3073

if(dret == -1){

3074

if(errno == EISDIR){

3075

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

3076

AT_REMOVEDIR);

3077

}

3078

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

3079

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

3080

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

3081

/* Recurse only in this special case */

3082

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

3083

dret = 0;

3084

}

3085

if(dret == -1){

3086

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

3087

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

3088

}

3089

}

3090

free(direntries[i]);

3091

}

3092

3093

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

3094

free(direntries);

3095

if(numentries == -1){

3096

perror_plus("scandirat");

3097

}

3098

dret = unlinkat(base, dirname, AT_REMOVEDIR);

3099

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

3100

perror_plus("rmdir");

3101

}

3102

} else {

3103

perror_plus("scandirat");

3104

}

3105

close(dir_fd);

2242

3106

}

2243

3107

2244

3108

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

2245

if(tempdir_created){

2246

struct dirent **direntries = NULL;

2247

struct dirent *direntry = NULL;

2248

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

2249

alphasort);

2250

if (numentries > 0){

2251

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

2252

direntry = direntries[i];

2253

char *fullname = NULL;

2254

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

2255

direntry->d_name);

2256

if(ret < 0){

2257

perror_plus("asprintf");

2258

continue;

2259

}

2260

ret = remove(fullname);

2261

if(ret == -1){

2262

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

2263

strerror(errno));

2264

}

2265

free(fullname);

2266

}

2267

}

2268

2269

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

2270

free(direntries);

2271

if (numentries == -1){

2272

perror_plus("scandir");

2273

}

2274

ret = rmdir(tempdir);

2275

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

2276

perror_plus("rmdir");

2277

}

3109

if(tempdir != NULL){

3110

clean_dir_at(-1, tempdir, 0);

2278

3111

}

2279

3112

2280

3113

if(quit_now){