/mandos/release : revision 237.16.13

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 /* not _LARGEFILE_SOURCE */

35

#endif

36

#ifndef _FILE_OFFSET_BITS

37

#define _FILE_OFFSET_BITS 64

38

#endif /* not _FILE_OFFSET_BITS */

38

#endif

39

40

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

41

42

#include <stdio.h> /* fprintf(), stderr, fwrite(),

43

stdout, ferror() */

44

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

43

stdout, ferror(), remove() */

44

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

45

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

46

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

47

strtof(), abort() */

55

opendir(), DIR */

56

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

57

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

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inet_pton(), connect(),

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getnameinfo() */

60

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

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inet_pton(), connect() */

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

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60

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

62

61

*/

63

62

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

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63

strtoimax() */

64

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

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

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program_invocation_short_name */

67

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

73

*/

74

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

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

76

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

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unlinkat() */

78

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

76

setgid(), pause() */

77

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

79

78

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

80

79

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

81

80

argp_state, struct argp,

88

87

EX_NOHOST, EX_IOERR, EX_PROTOCOL */

89

88

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

90

89

WEXITSTATUS(), WTERMSIG() */

91

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

92

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

93

argz_delete(), argz_append(),

94

argz_stringify(), argz_add(),

95

argz_count() */

96

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

97

EAI_SYSTEM, gai_strerror() */

98

90

99

91

#ifdef __linux__

100

92

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

142

134

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

143

135

char *connect_to = NULL;

144

136

const char *hookdir = HOOKDIR;

145

int hookdir_fd = -1;

146

uid_t uid = 65534;

147

gid_t gid = 65534;

148

137

149

138

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

150

139

typedef struct server{

151

140

const char *ip;

152

in_port_t port;

141

uint16_t port;

153

142

AvahiIfIndex if_index;

154

143

int af;

155

144

struct timespec last_seen;

159

148

160

149

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

161

150

typedef struct {

151

AvahiSimplePoll *simple_poll;

162

152

AvahiServer *server;

163

153

gnutls_certificate_credentials_t cred;

164

154

unsigned int dh_bits;

166

156

const char *priority;

167

157

gpgme_ctx_t ctx;

168

158

server *current_server;

169

char *interfaces;

170

size_t interfaces_size;

171

159

} mandos_context;

172

160

173

/* global so signal handler can reach it*/

174

AvahiSimplePoll *simple_poll;

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 };

175

166

176

167

sig_atomic_t quit_now = 0;

177

168

int signal_received = 0;

178

169

179

170

/* Function to use when printing errors */

180

171

void perror_plus(const char *print_text){

181

int e = errno;

182

172

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

183

173

program_invocation_short_name);

184

errno = e;

185

174

perror(print_text);

186

175

}

187

176

188

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

189

177

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

190

178

va_list ap;

191

179

va_start (ap, format);

192

180

193

181

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

194

182

program_invocation_short_name));

195

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

183

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

196

184

}

197

185

198

186

/*

200

188

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

201

189

* "buffer_length" is how much is already used.

202

190

*/

203

__attribute__((nonnull, warn_unused_result))

204

191

size_t incbuffer(char **buffer, size_t buffer_length,

205

192

size_t buffer_capacity){

206

193

if(buffer_length + BUFFER_SIZE > buffer_capacity){

207

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

208

if(new_buf == NULL){

209

int old_errno = errno;

210

free(*buffer);

211

errno = old_errno;

212

*buffer = NULL;

194

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

195

if(buffer == NULL){

213

196

return 0;

214

197

}

215

*buffer = new_buf;

216

198

buffer_capacity += BUFFER_SIZE;

217

199

}

218

200

return buffer_capacity;

219

201

}

220

202

221

203

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

222

__attribute__((nonnull, warn_unused_result))

223

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

224

int af, server **current_server){

204

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

205

int af){

225

206

int ret;

226

207

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

227

208

if(new_server == NULL){

228

209

perror_plus("malloc");

229

return false;

210

return -1;

230

211

}

231

212

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

232

213

.port = port,

234

215

.af = af };

235

216

if(new_server->ip == NULL){

236

217

perror_plus("strdup");

237

free(new_server);

238

return false;

239

}

240

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

241

if(ret == -1){

242

perror_plus("clock_gettime");

243

#ifdef __GNUC__

244

#pragma GCC diagnostic push

245

#pragma GCC diagnostic ignored "-Wcast-qual"

246

#endif

247

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

248

#ifdef __GNUC__

249

#pragma GCC diagnostic pop

250

#endif

251

free(new_server);

252

return false;

218

return -1;

253

219

}

254

220

/* Special case of first server */

255

if(*current_server == NULL){

221

if (mc.current_server == NULL){

256

222

new_server->next = new_server;

257

223

new_server->prev = new_server;

258

*current_server = new_server;

224

mc.current_server = new_server;

225

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

259

226

} else {

260

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

261

new_server->next = *current_server;

262

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

227

new_server->next = mc.current_server;

228

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

263

229

new_server->prev->next = new_server;

264

(*current_server)->prev = new_server;

265

}

266

return true;

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;

267

238

}

268

239

269

240

/*

270

241

* Initialize GPGME.

271

242

*/

272

__attribute__((nonnull, warn_unused_result))

273

static bool init_gpgme(const char * const seckey,

274

const char * const pubkey,

275

const char * const tempdir,

276

mandos_context *mc){

243

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

244

const char *tempdir){

277

245

gpgme_error_t rc;

278

246

gpgme_engine_info_t engine_info;

279

247

248

280

249

/*

281

250

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

282

251

*/

283

bool import_key(const char * const filename){

252

bool import_key(const char *filename){

284

253

int ret;

285

254

int fd;

286

255

gpgme_data_t pgp_data;

298

267

return false;

299

268

}

300

269

301

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

270

rc = gpgme_op_import(mc.ctx, pgp_data);

302

271

if(rc != GPG_ERR_NO_ERROR){

303

272

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

304

273

gpgme_strsource(rc), gpgme_strerror(rc));

348

317

}

349

318

350

319

/* Create new GPGME "context" */

351

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

320

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

352

321

if(rc != GPG_ERR_NO_ERROR){

353

322

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

354

323

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

367

336

* Decrypt OpenPGP data.

368

337

* Returns -1 on error

369

338

*/

370

__attribute__((nonnull, warn_unused_result))

371

339

static ssize_t pgp_packet_decrypt(const char *cryptotext,

372

340

size_t crypto_size,

373

char **plaintext,

374

mandos_context *mc){

341

char **plaintext){

375

342

gpgme_data_t dh_crypto, dh_plain;

376

343

gpgme_error_t rc;

377

344

ssize_t ret;

403

370

404

371

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

405

372

data buffer */

406

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

373

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

407

374

if(rc != GPG_ERR_NO_ERROR){

408

375

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

409

376

gpgme_strsource(rc), gpgme_strerror(rc));

410

377

plaintext_length = -1;

411

378

if(debug){

412

379

gpgme_decrypt_result_t result;

413

result = gpgme_op_decrypt_result(mc->ctx);

380

result = gpgme_op_decrypt_result(mc.ctx);

414

381

if(result == NULL){

415

382

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

416

383

} else {

493

460

return plaintext_length;

494

461

}

495

462

496

__attribute__((warn_unused_result))

497

static const char *safer_gnutls_strerror(int value){

498

const char *ret = gnutls_strerror(value);

463

static const char * safer_gnutls_strerror(int value){

464

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

465

-Wunreachable-code */

499

466

if(ret == NULL)

500

467

ret = "(unknown)";

501

468

return ret;

502

469

}

503

470

504

471

/* GnuTLS log function callback */

505

__attribute__((nonnull))

506

472

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

507

473

const char* string){

508

474

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

509

475

}

510

476

511

__attribute__((nonnull, warn_unused_result))

512

477

static int init_gnutls_global(const char *pubkeyfilename,

513

const char *seckeyfilename,

514

mandos_context *mc){

478

const char *seckeyfilename){

515

479

int ret;

516

480

517

481

if(debug){

534

498

}

535

499

536

500

/* OpenPGP credentials */

537

ret = gnutls_certificate_allocate_credentials(&mc->cred);

501

ret = gnutls_certificate_allocate_credentials(&mc.cred);

538

502

if(ret != GNUTLS_E_SUCCESS){

539

503

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

540

504

safer_gnutls_strerror(ret));

550

514

}

551

515

552

516

ret = gnutls_certificate_set_openpgp_key_file

553

(mc->cred, pubkeyfilename, seckeyfilename,

517

(mc.cred, pubkeyfilename, seckeyfilename,

554

518

GNUTLS_OPENPGP_FMT_BASE64);

555

519

if(ret != GNUTLS_E_SUCCESS){

556

520

fprintf_plus(stderr,

562

526

}

563

527

564

528

/* GnuTLS server initialization */

565

ret = gnutls_dh_params_init(&mc->dh_params);

529

ret = gnutls_dh_params_init(&mc.dh_params);

566

530

if(ret != GNUTLS_E_SUCCESS){

567

531

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

568

532

" initialization: %s\n",

569

533

safer_gnutls_strerror(ret));

570

534

goto globalfail;

571

535

}

572

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

536

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

573

537

if(ret != GNUTLS_E_SUCCESS){

574

538

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

575

539

safer_gnutls_strerror(ret));

576

540

goto globalfail;

577

541

}

578

542

579

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

543

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

580

544

581

545

return 0;

582

546

583

547

globalfail:

584

548

585

gnutls_certificate_free_credentials(mc->cred);

549

gnutls_certificate_free_credentials(mc.cred);

586

550

gnutls_global_deinit();

587

gnutls_dh_params_deinit(mc->dh_params);

551

gnutls_dh_params_deinit(mc.dh_params);

588

552

return -1;

589

553

}

590

554

591

__attribute__((nonnull, warn_unused_result))

592

static int init_gnutls_session(gnutls_session_t *session,

593

mandos_context *mc){

555

static int init_gnutls_session(gnutls_session_t *session){

594

556

int ret;

595

557

/* GnuTLS session creation */

596

558

do {

608

570

{

609

571

const char *err;

610

572

do {

611

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

573

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

612

574

if(quit_now){

613

575

gnutls_deinit(*session);

614

576

return -1;

625

587

626

588

do {

627

589

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

628

mc->cred);

590

mc.cred);

629

591

if(quit_now){

630

592

gnutls_deinit(*session);

631

593

return -1;

641

603

/* ignore client certificate if any. */

642

604

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

643

605

644

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

606

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

645

607

646

608

return 0;

647

609

}

650

612

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

651

613

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

652

614

653

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

654

__attribute__((warn_unused_result))

655

error_t raise_privileges(void){

656

error_t old_errno = errno;

657

error_t ret_errno = 0;

658

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

659

ret_errno = errno;

660

}

661

errno = old_errno;

662

return ret_errno;

663

}

664

665

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

666

__attribute__((warn_unused_result))

667

error_t raise_privileges_permanently(void){

668

error_t old_errno = errno;

669

error_t ret_errno = raise_privileges();

670

if(ret_errno != 0){

671

errno = old_errno;

672

return ret_errno;

673

}

674

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

675

ret_errno = errno;

676

}

677

errno = old_errno;

678

return ret_errno;

679

}

680

681

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

682

__attribute__((warn_unused_result))

683

error_t lower_privileges(void){

684

error_t old_errno = errno;

685

error_t ret_errno = 0;

686

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

687

ret_errno = errno;

688

}

689

errno = old_errno;

690

return ret_errno;

691

}

692

693

/* Lower privileges permanently */

694

__attribute__((warn_unused_result))

695

error_t lower_privileges_permanently(void){

696

error_t old_errno = errno;

697

error_t ret_errno = 0;

698

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

699

ret_errno = errno;

700

}

701

errno = old_errno;

702

return ret_errno;

703

}

704

705

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

706

__attribute__((nonnull, warn_unused_result))

707

static bool add_remove_local_route(const bool add,

708

const char *address,

709

AvahiIfIndex if_index){

710

int ret;

711

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

712

char add_arg[] = "add";

713

char remove_arg[] = "remove";

714

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

715

if(pluginhelperdir == NULL){

716

if(debug){

717

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

718

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

719

}

720

return false;

721

}

722

723

char interface[IF_NAMESIZE];

724

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

725

perror_plus("if_indextoname");

726

return false;

727

}

728

729

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

730

if(devnull == -1){

731

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

732

return false;

733

}

734

pid_t pid = fork();

735

if(pid == 0){

736

/* Child */

737

/* Raise privileges */

738

errno = raise_privileges_permanently();

739

if(errno != 0){

740

perror_plus("Failed to raise privileges");

741

/* _exit(EX_NOPERM); */

742

} else {

743

/* Set group */

744

errno = 0;

745

ret = setgid(0);

746

if(ret == -1){

747

perror_plus("setgid");

748

_exit(EX_NOPERM);

749

}

750

/* Reset supplementary groups */

751

errno = 0;

752

ret = setgroups(0, NULL);

753

if(ret == -1){

754

perror_plus("setgroups");

755

_exit(EX_NOPERM);

756

}

757

}

758

ret = dup2(devnull, STDIN_FILENO);

759

if(ret == -1){

760

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

761

_exit(EX_OSERR);

762

}

763

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

764

if(ret == -1){

765

perror_plus("close");

766

_exit(EX_OSERR);

767

}

768

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

769

if(ret == -1){

770

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

771

_exit(EX_OSERR);

772

}

773

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

774

O_RDONLY

775

| O_DIRECTORY

776

| O_PATH

777

| O_CLOEXEC));

778

if(helperdir_fd == -1){

779

perror_plus("open");

780

_exit(EX_UNAVAILABLE);

781

}

782

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

783

helper, O_RDONLY));

784

if(helper_fd == -1){

785

perror_plus("openat");

786

_exit(EX_UNAVAILABLE);

787

}

788

TEMP_FAILURE_RETRY(close(helperdir_fd));

789

#ifdef __GNUC__

790

#pragma GCC diagnostic push

791

#pragma GCC diagnostic ignored "-Wcast-qual"

792

#endif

793

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

794

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

795

interface, NULL }, environ) == -1){

796

#ifdef __GNUC__

797

#pragma GCC diagnostic pop

798

#endif

799

perror_plus("fexecve");

800

_exit(EXIT_FAILURE);

801

}

802

}

803

if(pid == -1){

804

perror_plus("fork");

805

return false;

806

}

807

int status;

808

pid_t pret = -1;

809

errno = 0;

810

do {

811

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

812

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

813

int errno_raising = 0;

814

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

815

errno_raising = errno;

816

perror_plus("Failed to raise privileges in order to"

817

" kill helper program");

818

}

819

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

820

perror_plus("kill");

821

}

822

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

823

perror_plus("Failed to lower privileges after killing"

824

" helper program");

825

}

826

return false;

827

}

828

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

829

if(pret == -1){

830

perror_plus("waitpid");

831

return false;

832

}

833

if(WIFEXITED(status)){

834

if(WEXITSTATUS(status) != 0){

835

fprintf_plus(stderr, "Error: iprouteadddel exited"

836

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

837

return false;

838

}

839

return true;

840

}

841

if(WIFSIGNALED(status)){

842

fprintf_plus(stderr, "Error: iprouteadddel died by"

843

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

844

return false;

845

}

846

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

847

return false;

848

}

849

850

__attribute__((nonnull, warn_unused_result))

851

static bool add_local_route(const char *address,

852

AvahiIfIndex if_index){

853

return add_remove_local_route(true, address, if_index);

854

}

855

856

__attribute__((nonnull, warn_unused_result))

857

static bool remove_local_route(const char *address,

858

AvahiIfIndex if_index){

859

return add_remove_local_route(false, address, if_index);

860

}

861

862

615

/* Called when a Mandos server is found */

863

__attribute__((nonnull, warn_unused_result))

864

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

616

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

865

617

AvahiIfIndex if_index,

866

int af, mandos_context *mc){

618

int af){

867

619

int ret, tcp_sd = -1;

868

620

ssize_t sret;

869

struct sockaddr_storage to;

621

union {

622

struct sockaddr_in in;

623

struct sockaddr_in6 in6;

624

} to;

870

625

char *buffer = NULL;

871

626

char *decrypted_buffer = NULL;

872

627

size_t buffer_length = 0;

875

630

int retval = -1;

876

631

gnutls_session_t session;

877

632

int pf; /* Protocol family */

878

bool route_added = false;

879

633

880

634

errno = 0;

881

635

897

651

return -1;

898

652

}

899

653

900

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

901

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

902

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

903

bool match = false;

904

{

905

char *interface = NULL;

906

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

907

interface))){

908

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

909

match = true;

910

break;

911

}

912

}

913

}

914

if(not match){

915

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

916

connect to the server */

917

if(debug){

918

char interface[IF_NAMESIZE];

919

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

920

perror_plus("if_indextoname");

921

} else {

922

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

923

" \"%s\"\n",

924

if_indextoname((unsigned int)if_index,

925

interface));

926

}

927

}

928

return -1;

929

}

930

}

931

932

ret = init_gnutls_session(&session, mc);

654

ret = init_gnutls_session(&session);

933

655

if(ret != 0){

934

656

return -1;

935

657

}

936

658

937

659

if(debug){

938

660

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

939

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

661

PRIu16 "\n", ip, port);

940

662

}

941

663

942

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

664

tcp_sd = socket(pf, SOCK_STREAM, 0);

943

665

if(tcp_sd < 0){

944

666

int e = errno;

945

667

perror_plus("socket");

954

676

955

677

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

956

678

if(af == AF_INET6){

957

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

958

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

679

to.in6.sin6_family = (sa_family_t)af;

680

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

959

681

} else { /* IPv4 */

960

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

961

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

682

to.in.sin_family = (sa_family_t)af;

683

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

962

684

}

963

685

if(ret < 0 ){

964

686

int e = errno;

973

695

goto mandos_end;

974

696

}

975

697

if(af == AF_INET6){

976

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

977

if(IN6_IS_ADDR_LINKLOCAL

978

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

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*/

979

705

if(if_index == AVAHI_IF_UNSPEC){

980

706

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

981

707

" incomplete without a network interface\n");

983

709

goto mandos_end;

984

710

}

985

711

/* Set the network interface number as scope */

986

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

712

to.in6.sin6_scope_id = (uint32_t)if_index;

987

713

}

988

714

} else {

989

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

715

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

716

-Wconversion and

717

-Wunreachable-code */

990

718

}

991

719

992

720

if(quit_now){

1000

728

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

1001

729

perror_plus("if_indextoname");

1002

730

} else {

1003

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

1004

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

731

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

732

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

1005

733

}

1006

734

} else {

1007

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

1008

ip, (uintmax_t)port);

735

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

736

ip, port);

1009

737

}

1010

738

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

1011

739

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

1012

if(af == AF_INET6){

1013

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

1014

sizeof(struct sockaddr_in6),

1015

addrstr, sizeof(addrstr), NULL, 0,

1016

NI_NUMERICHOST);

1017

} else {

1018

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

1019

sizeof(struct sockaddr_in),

1020

addrstr, sizeof(addrstr), NULL, 0,

1021

NI_NUMERICHOST);

1022

}

1023

if(ret == EAI_SYSTEM){

1024

perror_plus("getnameinfo");

1025

} else if(ret != 0) {

1026

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

1027

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

1028

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

1029

}

1030

}

1031

1032

if(quit_now){

1033

errno = EINTR;

1034

goto mandos_end;

1035

}

1036

1037

while(true){

1038

if(af == AF_INET6){

1039

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

1040

sizeof(struct sockaddr_in6));

1041

} else {

1042

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

1043

sizeof(struct sockaddr_in));

1044

}

1045

if(ret < 0){

1046

if(errno == ENETUNREACH

1047

and if_index != AVAHI_IF_UNSPEC

1048

and connect_to == NULL

1049

and not route_added and

1050

((af == AF_INET6 and not

1051

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1052

&to)->sin6_addr)))

1053

or (af == AF_INET and

1054

/* Not a a IPv4LL address */

1055

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

1056

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

1057

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

1058

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

1059

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

1060

connect to a Mandos server announced by Avahi on a server

1061

host with a global address. Work around this by retrying

1062

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

1063

1064

Avahi bug reference:

1065

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

1066

https://bugs.debian.org/587961

1067

*/

1068

int e = errno;

1069

route_added = add_local_route(ip, if_index);

1070

if(route_added){

1071

continue;

1072

}

1073

errno = e;

1074

}

1075

if(errno != ECONNREFUSED or debug){

1076

int e = errno;

1077

perror_plus("connect");

1078

errno = e;

1079

}

1080

goto mandos_end;

1081

}

1082

1083

if(quit_now){

1084

errno = EINTR;

1085

goto mandos_end;

1086

}

1087

break;

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;

1088

779

}

1089

780

1090

781

const char *out = mandos_protocol_version;

1126

817

goto mandos_end;

1127

818

}

1128

819

1129

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

1130

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

1131

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

1132

gnutls_transport_set_ptr(session,

1133

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

820

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

821

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

1134

822

1135

823

if(quit_now){

1136

824

errno = EINTR;

1241

929

if(buffer_length > 0){

1242

930

ssize_t decrypted_buffer_size;

1243

931

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

1244

&decrypted_buffer, mc);

932

&decrypted_buffer);

1245

933

if(decrypted_buffer_size >= 0){

1246

934

1247

935

written = 0;

1273

961

1274

962

mandos_end:

1275

963

{

1276

if(route_added){

1277

if(not remove_local_route(ip, if_index)){

1278

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

1279

" interface %d", ip, if_index);

1280

}

1281

}

1282

964

int e = errno;

1283

965

free(decrypted_buffer);

1284

966

free(buffer);

1301

983

return retval;

1302

984

}

1303

985

1304

__attribute__((nonnull))

1305

986

static void resolve_callback(AvahiSServiceResolver *r,

1306

987

AvahiIfIndex interface,

1307

988

AvahiProtocol proto,

1315

996

AVAHI_GCC_UNUSED AvahiStringList *txt,

1316

997

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1317

998

flags,

1318

void *mc){

1319

if(r == NULL){

1320

return;

1321

}

999

AVAHI_GCC_UNUSED void* userdata){

1000

assert(r);

1322

1001

1323

1002

/* Called whenever a service has been resolved successfully or

1324

1003

timed out */

1325

1004

1326

1005

if(quit_now){

1327

avahi_s_service_resolver_free(r);

1328

1006

return;

1329

1007

}

1330

1008

1334

1012

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

1335

1013

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

1336

1014

domain,

1337

avahi_strerror(avahi_server_errno

1338

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

1015

avahi_strerror(avahi_server_errno(mc.server)));

1339

1016

break;

1340

1017

1341

1018

case AVAHI_RESOLVER_FOUND:

1347

1024

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

1348

1025

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

1349

1026

}

1350

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

1351

interface,

1352

avahi_proto_to_af(proto),

1353

mc);

1027

int ret = start_mandos_communication(ip, port, interface,

1028

avahi_proto_to_af(proto));

1354

1029

if(ret == 0){

1355

avahi_simple_poll_quit(simple_poll);

1030

avahi_simple_poll_quit(mc.simple_poll);

1356

1031

} else {

1357

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

1358

avahi_proto_to_af(proto),

1359

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

1360

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

1361

" list\n", name);

1362

}

1032

ret = add_server(ip, port, interface,

1033

avahi_proto_to_af(proto));

1363

1034

}

1364

1035

}

1365

1036

}

1375

1046

const char *domain,

1376

1047

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1377

1048

flags,

1378

void *mc){

1379

if(b == NULL){

1380

return;

1381

}

1049

AVAHI_GCC_UNUSED void* userdata){

1050

assert(b);

1382

1051

1383

1052

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

1384

1053

is removed from the LAN */

1392

1061

case AVAHI_BROWSER_FAILURE:

1393

1062

1394

1063

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

1395

avahi_strerror(avahi_server_errno

1396

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

1397

avahi_simple_poll_quit(simple_poll);

1064

avahi_strerror(avahi_server_errno(mc.server)));

1065

avahi_simple_poll_quit(mc.simple_poll);

1398

1066

return;

1399

1067

1400

1068

case AVAHI_BROWSER_NEW:

1403

1071

the callback function is called the Avahi server will free the

1404

1072

resolver for us. */

1405

1073

1406

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

1407

interface, protocol, name, type,

1408

domain, protocol, 0,

1409

resolve_callback, mc) == NULL)

1074

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

1075

name, type, domain, protocol, 0,

1076

resolve_callback, NULL) == NULL)

1410

1077

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

1411

1078

" %s\n", name,

1412

avahi_strerror(avahi_server_errno

1413

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

1079

avahi_strerror(avahi_server_errno(mc.server)));

1414

1080

break;

1415

1081

1416

1082

case AVAHI_BROWSER_REMOVE:

1435

1101

signal_received = sig;

1436

1102

int old_errno = errno;

1437

1103

/* set main loop to exit */

1438

if(simple_poll != NULL){

1439

avahi_simple_poll_quit(simple_poll);

1104

if(mc.simple_poll != NULL){

1105

avahi_simple_poll_quit(mc.simple_poll);

1440

1106

}

1441

1107

errno = old_errno;

1442

1108

}

1443

1109

1444

__attribute__((nonnull, warn_unused_result))

1445

1110

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

1446

1111

int ret;

1447

error_t ret_errno;

1448

1112

1449

1113

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

1450

1114

if(s < 0){

1451

ret_errno = errno;

1452

1115

perror_plus("socket");

1453

errno = ret_errno;

1454

1116

return false;

1455

1117

}

1456

1118

strcpy(ifr->ifr_name, ifname);

1457

1119

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1458

1120

if(ret == -1){

1459

1121

if(debug){

1460

ret_errno = errno;

1461

1122

perror_plus("ioctl SIOCGIFFLAGS");

1462

errno = ret_errno;

1463

1123

}

1464

1124

return false;

1465

1125

}

1466

1126

return true;

1467

1127

}

1468

1128

1469

__attribute__((nonnull, warn_unused_result))

1470

1129

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

1471

1130

1472

1131

/* Reject the loopback device */

1514

1173

* corresponds to an acceptable network device.

1515

1174

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

1516

1175

*/

1517

__attribute__((nonnull, warn_unused_result))

1518

1176

int good_interface(const struct dirent *if_entry){

1519

1177

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

1520

1178

return 0;

1536

1194

}

1537

1195

1538

1196

/*

1539

* This function determines if a network interface is up.

1540

*/

1541

__attribute__((nonnull, warn_unused_result))

1542

bool interface_is_up(const char *interface){

1543

struct ifreq ifr;

1544

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

1545

if(debug){

1546

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

1547

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

1548

}

1549

return false;

1550

}

1551

1552

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

1553

}

1554

1555

/*

1556

* This function determines if a network interface is running

1557

*/

1558

__attribute__((nonnull, warn_unused_result))

1559

bool interface_is_running(const char *interface){

1560

struct ifreq ifr;

1561

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

1562

if(debug){

1563

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

1564

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

1565

}

1566

return false;

1567

}

1568

1569

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

1570

}

1571

1572

__attribute__((nonnull, pure, warn_unused_result))

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

1573

1239

int notdotentries(const struct dirent *direntry){

1574

1240

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

1575

1241

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

1582

1248

}

1583

1249

1584

1250

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

1585

__attribute__((nonnull, warn_unused_result))

1586

1251

int runnable_hook(const struct dirent *direntry){

1587

1252

int ret;

1588

1253

size_t sret;

1596

1261

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

1597

1262

"abcdefghijklmnopqrstuvwxyz"

1598

1263

"0123456789"

1599

"_.-");

1264

"_-");

1600

1265

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

1601

1266

/* Contains non-allowed characters */

1602

1267

if(debug){

1606

1271

return 0;

1607

1272

}

1608

1273

1609

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

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);

1610

1282

if(ret == -1){

1611

1283

if(debug){

1612

1284

perror_plus("Could not stat hook");

1636

1308

return 1;

1637

1309

}

1638

1310

1639

__attribute__((nonnull, warn_unused_result))

1640

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1641

mandos_context *mc){

1311

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1642

1312

int ret;

1643

1313

struct timespec now;

1644

1314

struct timespec waited_time;

1645

1315

intmax_t block_time;

1646

1316

1647

1317

while(true){

1648

if(mc->current_server == NULL){

1649

if(debug){

1318

if(mc.current_server == NULL){

1319

if (debug){

1650

1320

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

1651

1321

" No timeout!\n");

1652

1322

}

1653

1323

ret = avahi_simple_poll_iterate(s, -1);

1654

1324

} else {

1655

if(debug){

1325

if (debug){

1656

1326

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

1657

1327

" it, or wait\n");

1658

1328

}

1665

1335

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

1666

1336

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

1667

1337

waited_time.tv_sec = (now.tv_sec

1668

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

1338

- mc.current_server->last_seen.tv_sec);

1669

1339

waited_time.tv_nsec = (now.tv_nsec

1670

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

1340

- mc.current_server->last_seen.tv_nsec);

1671

1341

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

1672

1342

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

1673

1343

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

1675

1345

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

1676

1346

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

1677

1347

1678

if(debug){

1348

if (debug){

1679

1349

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

1680

1350

block_time);

1681

1351

}

1682

1352

1683

1353

if(block_time <= 0){

1684

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

1685

mc->current_server->port,

1686

mc->current_server->if_index,

1687

mc->current_server->af, mc);

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);

1688

1358

if(ret == 0){

1689

avahi_simple_poll_quit(s);

1359

avahi_simple_poll_quit(mc.simple_poll);

1690

1360

return 0;

1691

1361

}

1692

1362

ret = clock_gettime(CLOCK_MONOTONIC,

1693

&mc->current_server->last_seen);

1363

&mc.current_server->last_seen);

1694

1364

if(ret == -1){

1695

1365

perror_plus("clock_gettime");

1696

1366

return -1;

1697

1367

}

1698

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

1368

mc.current_server = mc.current_server->next;

1699

1369

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

1700

1370

servers, but don't block */

1701

1371

}

1703

1373

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

1704

1374

}

1705

1375

if(ret != 0){

1706

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

1376

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

1707

1377

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

1708

1378

}

1709

1379

}

1710

1380

}

1711

1381

}

1712

1382

1713

__attribute__((nonnull))

1714

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

1383

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

1715

1384

const float delay){

1716

struct dirent **direntries = NULL;

1717

if(hookdir_fd == -1){

1718

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

1719

| O_CLOEXEC);

1720

if(hookdir_fd == -1){

1721

if(errno == ENOENT){

1722

if(debug){

1723

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

1724

" found\n", hookdir);

1725

}

1726

} else {

1727

perror_plus("open");

1728

}

1729

return;

1730

}

1731

}

1732

#ifdef __GLIBC__

1733

#if __GLIBC_PREREQ(2, 15)

1734

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

1735

runnable_hook, alphasort);

1736

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

1737

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

1738

alphasort);

1739

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

1740

#else /* not __GLIBC__ */

1741

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

1742

alphasort);

1743

#endif /* not __GLIBC__ */

1385

struct dirent **direntries;

1386

struct dirent *direntry;

1387

int ret;

1388

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

1389

alphasort);

1744

1390

if(numhooks == -1){

1745

1391

perror_plus("scandir");

1746

return;

1747

}

1748

struct dirent *direntry;

1749

int ret;

1750

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

1751

if(devnull == -1){

1752

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

1753

return;

1754

}

1755

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

1756

direntry = direntries[i];

1757

if(debug){

1758

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

1759

direntry->d_name);

1760

}

1761

pid_t hook_pid = fork();

1762

if(hook_pid == 0){

1763

/* Child */

1764

/* Raise privileges */

1765

errno = raise_privileges_permanently();

1766

if(errno != 0){

1767

perror_plus("Failed to raise privileges");

1768

_exit(EX_NOPERM);

1769

}

1770

/* Set group */

1771

errno = 0;

1772

ret = setgid(0);

1773

if(ret == -1){

1774

perror_plus("setgid");

1775

_exit(EX_NOPERM);

1776

}

1777

/* Reset supplementary groups */

1778

errno = 0;

1779

ret = setgroups(0, NULL);

1780

if(ret == -1){

1781

perror_plus("setgroups");

1782

_exit(EX_NOPERM);

1783

}

1784

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

1785

if(ret == -1){

1786

perror_plus("setenv");

1787

_exit(EX_OSERR);

1788

}

1789

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

1790

if(ret == -1){

1791

perror_plus("setenv");

1792

_exit(EX_OSERR);

1793

}

1794

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

1795

if(ret == -1){

1796

perror_plus("setenv");

1797

_exit(EX_OSERR);

1798

}

1799

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

1800

if(ret == -1){

1801

perror_plus("setenv");

1802

_exit(EX_OSERR);

1803

}

1804

char *delaystring;

1805

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

1806

if(ret == -1){

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){

1807

1399

perror_plus("asprintf");

1808

_exit(EX_OSERR);

1809

}

1810

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

1811

if(ret == -1){

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

}

1812

1444

free(delaystring);

1813

perror_plus("setenv");

1814

_exit(EX_OSERR);

1815

}

1816

free(delaystring);

1817

if(connect_to != NULL){

1818

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

1819

if(ret == -1){

1820

perror_plus("setenv");

1821

_exit(EX_OSERR);

1822

}

1823

}

1824

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

1825

direntry->d_name,

1826

O_RDONLY));

1827

if(hook_fd == -1){

1828

perror_plus("openat");

1829

_exit(EXIT_FAILURE);

1830

}

1831

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

1832

perror_plus("close");

1833

_exit(EXIT_FAILURE);

1834

}

1835

ret = dup2(devnull, STDIN_FILENO);

1836

if(ret == -1){

1837

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

1838

_exit(EX_OSERR);

1839

}

1840

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

1841

if(ret == -1){

1842

perror_plus("close");

1843

_exit(EX_OSERR);

1844

}

1845

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1846

if(ret == -1){

1847

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

1848

_exit(EX_OSERR);

1849

}

1850

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

1851

environ) == -1){

1852

perror_plus("fexecve");

1853

_exit(EXIT_FAILURE);

1854

}

1855

} else {

1856

if(hook_pid == -1){

1857

perror_plus("fork");

1858

free(direntry);

1859

continue;

1860

}

1861

int status;

1862

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

1863

perror_plus("waitpid");

1864

free(direntry);

1865

continue;

1866

}

1867

if(WIFEXITED(status)){

1868

if(WEXITSTATUS(status) != 0){

1869

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

1870

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

1871

WEXITSTATUS(status));

1872

free(direntry);

1873

continue;

1874

}

1875

} else if(WIFSIGNALED(status)){

1876

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

1877

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

1878

WTERMSIG(status));

1879

free(direntry);

1880

continue;

1881

} else {

1882

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

1883

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

1884

free(direntry);

1885

continue;

1886

}

1887

}

1888

if(debug){

1889

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

1890

direntry->d_name);

1891

}

1892

free(direntry);

1893

}

1894

free(direntries);

1895

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

1896

perror_plus("close");

1897

} else {

1898

hookdir_fd = -1;

1899

}

1900

close(devnull);

1901

}

1902

1903

__attribute__((nonnull, warn_unused_result))

1904

error_t bring_up_interface(const char *const interface,

1905

const float delay){

1906

error_t old_errno = errno;

1907

int ret;

1908

struct ifreq network;

1909

unsigned int if_index = if_nametoindex(interface);

1910

if(if_index == 0){

1911

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

1912

errno = old_errno;

1913

return ENXIO;

1914

}

1915

1916

if(quit_now){

1917

errno = old_errno;

1918

return EINTR;

1919

}

1920

1921

if(not interface_is_up(interface)){

1922

error_t ret_errno = 0, ioctl_errno = 0;

1923

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

1924

ret_errno = errno;

1925

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

1926

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

1927

errno = old_errno;

1928

return ret_errno;

1929

}

1930

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

1931

1932

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

1933

if(sd == -1){

1934

ret_errno = errno;

1935

perror_plus("socket");

1936

errno = old_errno;

1937

return ret_errno;

1938

}

1939

1940

if(quit_now){

1941

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

1942

if(ret == -1){

1943

perror_plus("close");

1944

}

1945

errno = old_errno;

1946

return EINTR;

1947

}

1948

1949

if(debug){

1950

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

1951

interface);

1952

}

1953

1954

/* Raise privileges */

1955

ret_errno = raise_privileges();

1956

if(ret_errno != 0){

1957

errno = ret_errno;

1958

perror_plus("Failed to raise privileges");

1959

}

1960

1961

#ifdef __linux__

1962

int ret_linux;

1963

bool restore_loglevel = false;

1964

if(ret_errno == 0){

1965

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1966

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

1967

ret_linux = klogctl(8, NULL, 5);

1968

if(ret_linux == -1){

1969

perror_plus("klogctl");

1970

} else {

1971

restore_loglevel = true;

1972

}

1973

}

1974

#endif /* __linux__ */

1975

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

1976

ioctl_errno = errno;

1977

#ifdef __linux__

1978

if(restore_loglevel){

1979

ret_linux = klogctl(7, NULL, 0);

1980

if(ret_linux == -1){

1981

perror_plus("klogctl");

1982

}

1983

}

1984

#endif /* __linux__ */

1985

1986

/* If raise_privileges() succeeded above */

1987

if(ret_errno == 0){

1988

/* Lower privileges */

1989

ret_errno = lower_privileges();

1990

if(ret_errno != 0){

1991

errno = ret_errno;

1992

perror_plus("Failed to lower privileges");

1993

}

1994

}

1995

1996

/* Close the socket */

1997

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

1998

if(ret == -1){

1999

perror_plus("close");

2000

}

2001

2002

if(ret_setflags == -1){

2003

errno = ioctl_errno;

2004

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

2005

errno = old_errno;

2006

return ioctl_errno;

2007

}

2008

} else if(debug){

2009

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

2010

interface);

2011

}

2012

2013

/* Sleep checking until interface is running.

2014

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

2015

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

2016

if(interface_is_running(interface)){

2017

break;

2018

}

2019

struct timespec sleeptime = { .tv_nsec = 250000000 };

2020

ret = nanosleep(&sleeptime, NULL);

2021

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

2022

perror_plus("nanosleep");

2023

}

2024

}

2025

2026

errno = old_errno;

2027

return 0;

2028

}

2029

2030

__attribute__((nonnull, warn_unused_result))

2031

error_t take_down_interface(const char *const interface){

2032

error_t old_errno = errno;

2033

struct ifreq network;

2034

unsigned int if_index = if_nametoindex(interface);

2035

if(if_index == 0){

2036

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

2037

errno = old_errno;

2038

return ENXIO;

2039

}

2040

if(interface_is_up(interface)){

2041

error_t ret_errno = 0, ioctl_errno = 0;

2042

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

2043

ret_errno = errno;

2044

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

2045

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

2046

errno = old_errno;

2047

return ret_errno;

2048

}

2049

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

2050

2051

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

2052

if(sd == -1){

2053

ret_errno = errno;

2054

perror_plus("socket");

2055

errno = old_errno;

2056

return ret_errno;

2057

}

2058

2059

if(debug){

2060

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

2061

interface);

2062

}

2063

2064

/* Raise privileges */

2065

ret_errno = raise_privileges();

2066

if(ret_errno != 0){

2067

errno = ret_errno;

2068

perror_plus("Failed to raise privileges");

2069

}

2070

2071

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

2072

ioctl_errno = errno;

2073

2074

/* If raise_privileges() succeeded above */

2075

if(ret_errno == 0){

2076

/* Lower privileges */

2077

ret_errno = lower_privileges();

2078

if(ret_errno != 0){

2079

errno = ret_errno;

2080

perror_plus("Failed to lower privileges");

2081

}

2082

}

2083

2084

/* Close the socket */

2085

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

2086

if(ret == -1){

2087

perror_plus("close");

2088

}

2089

2090

if(ret_setflags == -1){

2091

errno = ioctl_errno;

2092

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2093

errno = old_errno;

2094

return ioctl_errno;

2095

}

2096

} else if(debug){

2097

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

2098

interface);

2099

}

2100

2101

errno = old_errno;

2102

return 0;

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;

2103

1484

}

2104

1485

2105

1486

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

2106

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

2107

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

2108

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

2109

.interfaces = NULL, .interfaces_size = 0 };

2110

1487

AvahiSServiceBrowser *sb = NULL;

2111

error_t ret_errno;

1488

int error;

2112

1489

int ret;

2113

1490

intmax_t tmpmax;

2114

1491

char *tmp;

2115

1492

int exitcode = EXIT_SUCCESS;

2116

char *interfaces_to_take_down = NULL;

2117

size_t interfaces_to_take_down_size = 0;

2118

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

2119

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

2120

char *tempdir = NULL;

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;

2121

1501

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

2122

1502

const char *seckey = PATHDIR "/" SECKEY;

2123

1503

const char *pubkey = PATHDIR "/" PUBKEY;

2124

char *interfaces_hooks = NULL;

2125

1504

2126

1505

bool gnutls_initialized = false;

2127

1506

bool gpgme_initialized = false;

2189

1568

.group = 2 },

2190

1569

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

2191

1570

.arg = "SECONDS",

2192

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

1571

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

2193

1572

.group = 2 },

2194

1573

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

2195

1574

.arg = "DIR",

2218

1597

connect_to = arg;

2219

1598

break;

2220

1599

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

2221

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

2222

arg, (int)',');

2223

if(ret_errno != 0){

2224

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

2225

}

1600

interface = arg;

2226

1601

break;

2227

1602

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

2228

1603

seckey = arg;

2271

1646

argp_state_help(state, state->out_stream,

2272

1647

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

2273

1648

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

1649

fprintf_plus(state->out_stream,

1650

"Mandos plugin mandos-client: ");

2274

1651

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

2275

1652

exit(argp_err_exit_status);

2276

1653

break;

2300

1677

goto end;

2301

1678

}

2302

1679

}

2303

2304

{

1680

1681

if(getuid() == 0){

2305

1682

/* Work around Debian bug #633582:

2306

1683

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

2307

2308

/* Re-raise privileges */

2309

ret_errno = raise_privileges();

2310

if(ret_errno != 0){

2311

errno = ret_errno;

2312

perror_plus("Failed to raise privileges");

2313

} else {

2314

struct stat st;

2315

2316

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

2317

int seckey_fd = open(seckey, O_RDONLY);

2318

if(seckey_fd == -1){

2319

perror_plus("open");

2320

} else {

2321

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

2322

if(ret == -1){

2323

perror_plus("fstat");

2324

} else {

2325

if(S_ISREG(st.st_mode)

2326

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

2327

ret = fchown(seckey_fd, uid, gid);

2328

if(ret == -1){

2329

perror_plus("fchown");

2330

}

2331

}

2332

}

2333

TEMP_FAILURE_RETRY(close(seckey_fd));

2334

}

2335

}

2336

2337

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

2338

int pubkey_fd = open(pubkey, O_RDONLY);

2339

if(pubkey_fd == -1){

2340

perror_plus("open");

2341

} else {

2342

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

2343

if(ret == -1){

2344

perror_plus("fstat");

2345

} else {

2346

if(S_ISREG(st.st_mode)

2347

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

2348

ret = fchown(pubkey_fd, uid, gid);

2349

if(ret == -1){

2350

perror_plus("fchown");

2351

}

2352

}

2353

}

2354

TEMP_FAILURE_RETRY(close(pubkey_fd));

2355

}

2356

}

2357

2358

/* Lower privileges */

2359

ret_errno = lower_privileges();

2360

if(ret_errno != 0){

2361

errno = ret_errno;

2362

perror_plus("Failed to lower privileges");

2363

}

2364

}

2365

}

2366

2367

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

2368

{

2369

char *interface = NULL;

2370

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

2371

interface))){

2372

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

2373

and if_nametoindex(interface) == 0){

2374

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

2375

fprintf_plus(stderr, "Not using nonexisting interface"

2376

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

2377

}

2378

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

2379

interface = NULL;

2380

}

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");

2381

1740

}

2382

1741

}

2383

1742

2384

1743

/* Run network hooks */

2385

1744

{

2386

if(mc.interfaces != NULL){

2387

interfaces_hooks = malloc(mc.interfaces_size);

2388

if(interfaces_hooks == NULL){

2389

perror_plus("malloc");

2390

goto end;

2391

}

2392

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

2393

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

2394

}

2395

run_network_hooks("start", interfaces_hooks != NULL ?

2396

interfaces_hooks : "", delay);

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

}

2397

1764

}

2398

1765

2399

1766

if(not debug){

2400

1767

avahi_set_log_function(empty_log);

2401

1768

}

2402

1769

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

2403

1802

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

2404

1803

from the signal handler */

2405

1804

/* Initialize the pseudo-RNG for Avahi */

2406

1805

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

2407

simple_poll = avahi_simple_poll_new();

2408

if(simple_poll == NULL){

1806

mc.simple_poll = avahi_simple_poll_new();

1807

if(mc.simple_poll == NULL){

2409

1808

fprintf_plus(stderr,

2410

1809

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

2411

1810

exitcode = EX_UNAVAILABLE;

2475

1874

}

2476

1875

}

2477

1876

2478

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

2479

if(mc.interfaces == NULL){

2480

struct dirent **direntries = NULL;

2481

/* Look for any good interfaces */

2482

ret = scandir(sys_class_net, &direntries, good_interface,

2483

alphasort);

2484

if(ret >= 1){

2485

/* Add all found interfaces to interfaces list */

2486

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

2487

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

2488

direntries[i]->d_name);

2489

if(ret_errno != 0){

2490

errno = ret_errno;

2491

perror_plus("argz_add");

2492

free(direntries[i]);

2493

continue;

2494

}

2495

if(debug){

2496

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

2497

direntries[i]->d_name);

2498

}

2499

free(direntries[i]);

2500

}

2501

free(direntries);

2502

} else {

2503

if(ret == 0){

2504

free(direntries);

2505

}

2506

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

2507

exitcode = EXIT_FAILURE;

2508

goto end;

2509

}

2510

}

2511

2512

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

2513

{

2514

char *interface = NULL;

2515

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

2516

interface))){

2517

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

2518

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

2519

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

2520

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

2521

interface);

2522

interface = NULL;

2523

while((interface = argz_next(mc.interfaces,

2524

mc.interfaces_size, interface))){

2525

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

2526

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

2527

interface);

2528

interface = NULL;

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");

2529

1962

}

2530

1963

}

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){

2531

1981

break;

2532

1982

}

2533

bool interface_was_up = interface_is_up(interface);

2534

errno = bring_up_interface(interface, delay);

2535

if(not interface_was_up){

2536

if(errno != 0){

2537

perror_plus("Failed to bring up interface");

2538

} else {

2539

errno = argz_add(&interfaces_to_take_down,

2540

&interfaces_to_take_down_size,

2541

interface);

2542

if(errno != 0){

2543

perror_plus("argz_add");

2544

}

2545

}

2546

}

2547

}

2548

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

2549

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

2550

}

2551

}

2552

2553

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

2554

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

2555

if(debug){

2556

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

2557

mc.interfaces);

2558

}

2559

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

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

}

2560

2012

}

2561

2013

2562

2014

if(quit_now){

2563

2015

goto end;

2564

2016

}

2565

2017

2566

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

2018

ret = init_gnutls_global(pubkey, seckey);

2567

2019

if(ret == -1){

2568

2020

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

2569

2021

exitcode = EX_UNAVAILABLE;

2576

2028

goto end;

2577

2029

}

2578

2030

2579

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

2580

tempdir = mkdtemp(run_tempdir);

2581

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

2582

if(debug){

2583

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

2584

run_tempdir, old_tempdir);

2585

}

2586

tempdir = mkdtemp(old_tempdir);

2587

}

2588

if(tempdir == NULL){

2031

if(mkdtemp(tempdir) == NULL){

2589

2032

perror_plus("mkdtemp");

2590

2033

goto end;

2591

2034

}

2035

tempdir_created = true;

2592

2036

2593

2037

if(quit_now){

2594

2038

goto end;

2595

2039

}

2596

2040

2597

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

2041

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

2598

2042

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

2599

2043

exitcode = EX_UNAVAILABLE;

2600

2044

goto end;

2610

2054

/* Connect directly, do not use Zeroconf */

2611

2055

/* (Mainly meant for debugging) */

2612

2056

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

2613

2614

2057

if(address == NULL){

2615

2058

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

2616

2059

exitcode = EX_USAGE;

2621

2064

goto end;

2622

2065

}

2623

2066

2624

in_port_t port;

2067

uint16_t port;

2625

2068

errno = 0;

2626

2069

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

2627

2070

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

2628

or tmpmax != (in_port_t)tmpmax){

2071

or tmpmax != (uint16_t)tmpmax){

2629

2072

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

2630

2073

exitcode = EX_USAGE;

2631

2074

goto end;

2632

2075

}

2633

2076

2634

2077

if(quit_now){

2635

2078

goto end;

2636

2079

}

2637

2080

2638

port = (in_port_t)tmpmax;

2081

port = (uint16_t)tmpmax;

2639

2082

*address = '\0';

2640

2083

/* Colon in address indicates IPv6 */

2641

2084

int af;

2657

2100

}

2658

2101

2659

2102

while(not quit_now){

2660

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

2661

&mc);

2103

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

2662

2104

if(quit_now or ret == 0){

2663

2105

break;

2664

2106

}

2666

2108

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

2667

2109

(int)retry_interval);

2668

2110

}

2669

sleep((unsigned int)retry_interval);

2111

sleep((int)retry_interval);

2670

2112

}

2671

2113

2672

if(not quit_now){

2114

if (not quit_now){

2673

2115

exitcode = EXIT_SUCCESS;

2674

2116

}

2675

2117

2690

2132

config.publish_domain = 0;

2691

2133

2692

2134

/* Allocate a new server */

2693

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2694

&config, NULL, NULL, &ret_errno);

2135

mc.server = avahi_server_new(avahi_simple_poll_get

2136

(mc.simple_poll), &config, NULL,

2137

NULL, &error);

2695

2138

2696

2139

/* Free the Avahi configuration data */

2697

2140

avahi_server_config_free(&config);

2700

2143

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

2701

2144

if(mc.server == NULL){

2702

2145

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

2703

avahi_strerror(ret_errno));

2146

avahi_strerror(error));

2704

2147

exitcode = EX_UNAVAILABLE;

2705

2148

goto end;

2706

2149

}

2712

2155

/* Create the Avahi service browser */

2713

2156

sb = avahi_s_service_browser_new(mc.server, if_index,

2714

2157

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2715

NULL, 0, browse_callback,

2716

(void *)&mc);

2158

NULL, 0, browse_callback, NULL);

2717

2159

if(sb == NULL){

2718

2160

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

2719

2161

avahi_strerror(avahi_server_errno(mc.server)));

2730

2172

if(debug){

2731

2173

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

2732

2174

}

2733

2734

ret = avahi_loop_with_timeout(simple_poll,

2735

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

2175

2176

ret = avahi_loop_with_timeout(mc.simple_poll,

2177

(int)(retry_interval * 1000));

2736

2178

if(debug){

2737

2179

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

2738

2180

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

2745

2187

}

2746

2188

2747

2189

/* Cleanup things */

2748

free(mc.interfaces);

2749

2750

2190

if(sb != NULL)

2751

2191

avahi_s_service_browser_free(sb);

2752

2192

2753

2193

if(mc.server != NULL)

2754

2194

avahi_server_free(mc.server);

2755

2195

2756

if(simple_poll != NULL)

2757

avahi_simple_poll_free(simple_poll);

2196

if(mc.simple_poll != NULL)

2197

avahi_simple_poll_free(mc.simple_poll);

2758

2198

2759

2199

if(gnutls_initialized){

2760

2200

gnutls_certificate_free_credentials(mc.cred);

2772

2212

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

2773

2213

while(mc.current_server != NULL){

2774

2214

server *next = mc.current_server->next;

2775

#ifdef __GNUC__

2776

#pragma GCC diagnostic push

2777

#pragma GCC diagnostic ignored "-Wcast-qual"

2778

#endif

2779

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

2780

#ifdef __GNUC__

2781

#pragma GCC diagnostic pop

2782

#endif

2783

2215

free(mc.current_server);

2784

2216

mc.current_server = next;

2785

2217

}

2786

2218

}

2787

2219

2788

/* Re-raise privileges */

2220

/* Re-raise priviliges */

2789

2221

{

2790

ret_errno = raise_privileges();

2791

if(ret_errno != 0){

2792

errno = ret_errno;

2793

perror_plus("Failed to raise privileges");

2794

} else {

2795

2796

/* Run network hooks */

2797

run_network_hooks("stop", interfaces_hooks != NULL ?

2798

interfaces_hooks : "", delay);

2799

2800

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

2801

{

2802

char *interface = NULL;

2803

while((interface=argz_next(interfaces_to_take_down,

2804

interfaces_to_take_down_size,

2805

interface))){

2806

ret_errno = take_down_interface(interface);

2807

if(ret_errno != 0){

2808

errno = ret_errno;

2809

perror_plus("Failed to take down interface");

2810

}

2811

}

2812

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

2813

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

2814

" down\n");

2815

}

2816

}

2817

}

2818

2819

ret_errno = lower_privileges_permanently();

2820

if(ret_errno != 0){

2821

errno = ret_errno;

2822

perror_plus("Failed to lower privileges permanently");

2823

}

2824

}

2825

2826

free(interfaces_to_take_down);

2827

free(interfaces_hooks);

2222

if(getuid() == 0){

2223

errno = 0;

2224

ret = seteuid(0);

2225

if(ret == -1){

2226

perror_plus("seteuid");

2227

}

2228

}

2229

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

}

2249

}

2250

}

2251

if(getuid() == 0){

2252

/* Lower privileges permanently */

2253

errno = 0;

2254

ret = setuid(uid);

2255

if(ret == -1){

2256

perror_plus("setuid");

2257

}

2258

}

2828

2259

2829

2260

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

2830

if(tempdir != NULL){

2261

if(tempdir_created){

2831

2262

struct dirent **direntries = NULL;

2832

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

2833

| O_NOFOLLOW

2834

| O_DIRECTORY

2835

| O_PATH));

2836

if(tempdir_fd == -1){

2837

perror_plus("open");

2838

} else {

2839

#ifdef __GLIBC__

2840

#if __GLIBC_PREREQ(2, 15)

2841

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

2842

notdotentries, alphasort);

2843

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

2844

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

2845

alphasort);

2846

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

2847

#else /* not __GLIBC__ */

2848

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

2849

alphasort);

2850

#endif /* not __GLIBC__ */

2851

if(numentries >= 0){

2852

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

2853

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

2854

if(ret == -1){

2855

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

2856

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

2857

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

2858

}

2859

free(direntries[i]);

2860

}

2861

2862

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

2863

free(direntries);

2864

if(numentries == -1){

2865

perror_plus("scandir");

2866

}

2867

ret = rmdir(tempdir);

2868

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

2869

perror_plus("rmdir");

2870

}

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);

2871

2282

}

2872

TEMP_FAILURE_RETRY(close(tempdir_fd));

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");

2873

2293

}

2874

2294

}

2875

2295