/mandos/release : revision 237.16.24

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() */

59

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

61

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() */

65

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

66

program_invocation_short_name */

67

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

73

*/

74

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

75

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

76

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

77

unlinkat() */

78

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

76

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

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,

89

88

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

90

89

WEXITSTATUS(), WTERMSIG() */

91

90

#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

91

99

92

#ifdef __linux__

100

93

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

142

135

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

143

136

char *connect_to = NULL;

144

137

const char *hookdir = HOOKDIR;

145

int hookdir_fd = -1;

146

uid_t uid = 65534;

147

gid_t gid = 65534;

148

138

149

139

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

150

140

typedef struct server{

151

141

const char *ip;

152

in_port_t port;

142

uint16_t port;

153

143

AvahiIfIndex if_index;

154

144

int af;

155

145

struct timespec last_seen;

159

149

160

150

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

161

151

typedef struct {

152

AvahiSimplePoll *simple_poll;

162

153

AvahiServer *server;

163

154

gnutls_certificate_credentials_t cred;

164

155

unsigned int dh_bits;

166

157

const char *priority;

167

158

gpgme_ctx_t ctx;

168

159

server *current_server;

169

char *interfaces;

170

size_t interfaces_size;

171

160

} mandos_context;

172

161

173

/* global so signal handler can reach it*/

174

AvahiSimplePoll *simple_poll;

162

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

163

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

164

.dh_bits = 1024, .priority = "SECURE256"

165

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

166

.current_server = NULL };

175

167

176

168

sig_atomic_t quit_now = 0;

177

169

int signal_received = 0;

178

170

179

171

/* Function to use when printing errors */

180

172

void perror_plus(const char *print_text){

181

int e = errno;

182

173

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

183

174

program_invocation_short_name);

184

errno = e;

185

175

perror(print_text);

186

176

}

187

177

188

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

189

178

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

190

179

va_list ap;

191

180

va_start (ap, format);

192

181

193

182

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

194

183

program_invocation_short_name));

195

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

184

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

196

185

}

197

186

198

187

/*

200

189

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

201

190

* "buffer_length" is how much is already used.

202

191

*/

203

__attribute__((nonnull, warn_unused_result))

204

192

size_t incbuffer(char **buffer, size_t buffer_length,

205

193

size_t buffer_capacity){

206

194

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;

195

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

196

if(buffer == NULL){

213

197

return 0;

214

198

}

215

*buffer = new_buf;

216

199

buffer_capacity += BUFFER_SIZE;

217

200

}

218

201

return buffer_capacity;

219

202

}

220

203

221

204

/* 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){

205

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

206

int af){

225

207

int ret;

226

208

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

227

209

if(new_server == NULL){

228

210

perror_plus("malloc");

229

return false;

211

return -1;

230

212

}

231

213

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

232

214

.port = port,

234

216

.af = af };

235

217

if(new_server->ip == NULL){

236

218

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;

219

return -1;

253

220

}

254

221

/* Special case of first server */

255

if(*current_server == NULL){

222

if (mc.current_server == NULL){

256

223

new_server->next = new_server;

257

224

new_server->prev = new_server;

258

*current_server = new_server;

225

mc.current_server = new_server;

226

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

259

227

} else {

260

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

261

new_server->next = *current_server;

262

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

228

new_server->next = mc.current_server;

229

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

263

230

new_server->prev->next = new_server;

264

(*current_server)->prev = new_server;

265

}

266

return true;

231

mc.current_server->prev = new_server;

232

}

233

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

234

if(ret == -1){

235

perror_plus("clock_gettime");

236

return -1;

237

}

238

return 0;

267

239

}

268

240

269

241

/*

270

242

* Initialize GPGME.

271

243

*/

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){

244

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

245

const char *tempdir){

277

246

gpgme_error_t rc;

278

247

gpgme_engine_info_t engine_info;

279

248

249

280

250

/*

281

251

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

282

252

*/

283

bool import_key(const char * const filename){

253

bool import_key(const char *filename){

284

254

int ret;

285

255

int fd;

286

256

gpgme_data_t pgp_data;

298

268

return false;

299

269

}

300

270

301

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

271

rc = gpgme_op_import(mc.ctx, pgp_data);

302

272

if(rc != GPG_ERR_NO_ERROR){

303

273

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

304

274

gpgme_strsource(rc), gpgme_strerror(rc));

348

318

}

349

319

350

320

/* Create new GPGME "context" */

351

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

321

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

352

322

if(rc != GPG_ERR_NO_ERROR){

353

323

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

354

324

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

367

337

* Decrypt OpenPGP data.

368

338

* Returns -1 on error

369

339

*/

370

__attribute__((nonnull, warn_unused_result))

371

340

static ssize_t pgp_packet_decrypt(const char *cryptotext,

372

341

size_t crypto_size,

373

char **plaintext,

374

mandos_context *mc){

342

char **plaintext){

375

343

gpgme_data_t dh_crypto, dh_plain;

376

344

gpgme_error_t rc;

377

345

ssize_t ret;

403

371

404

372

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

405

373

data buffer */

406

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

374

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

407

375

if(rc != GPG_ERR_NO_ERROR){

408

376

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

409

377

gpgme_strsource(rc), gpgme_strerror(rc));

410

378

plaintext_length = -1;

411

379

if(debug){

412

380

gpgme_decrypt_result_t result;

413

result = gpgme_op_decrypt_result(mc->ctx);

381

result = gpgme_op_decrypt_result(mc.ctx);

414

382

if(result == NULL){

415

383

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

416

384

} else {

493

461

return plaintext_length;

494

462

}

495

463

496

__attribute__((warn_unused_result))

497

static const char *safer_gnutls_strerror(int value){

498

const char *ret = gnutls_strerror(value);

464

static const char * safer_gnutls_strerror(int value){

465

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

466

-Wunreachable-code */

499

467

if(ret == NULL)

500

468

ret = "(unknown)";

501

469

return ret;

502

470

}

503

471

504

472

/* GnuTLS log function callback */

505

__attribute__((nonnull))

506

473

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

507

474

const char* string){

508

475

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

509

476

}

510

477

511

__attribute__((nonnull, warn_unused_result))

512

478

static int init_gnutls_global(const char *pubkeyfilename,

513

const char *seckeyfilename,

514

mandos_context *mc){

479

const char *seckeyfilename){

515

480

int ret;

516

481

517

482

if(debug){

534

499

}

535

500

536

501

/* OpenPGP credentials */

537

ret = gnutls_certificate_allocate_credentials(&mc->cred);

502

ret = gnutls_certificate_allocate_credentials(&mc.cred);

538

503

if(ret != GNUTLS_E_SUCCESS){

539

504

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

540

505

safer_gnutls_strerror(ret));

550

515

}

551

516

552

517

ret = gnutls_certificate_set_openpgp_key_file

553

(mc->cred, pubkeyfilename, seckeyfilename,

518

(mc.cred, pubkeyfilename, seckeyfilename,

554

519

GNUTLS_OPENPGP_FMT_BASE64);

555

520

if(ret != GNUTLS_E_SUCCESS){

556

521

fprintf_plus(stderr,

562

527

}

563

528

564

529

/* GnuTLS server initialization */

565

ret = gnutls_dh_params_init(&mc->dh_params);

530

ret = gnutls_dh_params_init(&mc.dh_params);

566

531

if(ret != GNUTLS_E_SUCCESS){

567

532

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

568

533

" initialization: %s\n",

569

534

safer_gnutls_strerror(ret));

570

535

goto globalfail;

571

536

}

572

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

537

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

573

538

if(ret != GNUTLS_E_SUCCESS){

574

539

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

575

540

safer_gnutls_strerror(ret));

576

541

goto globalfail;

577

542

}

578

543

579

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

544

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

580

545

581

546

return 0;

582

547

583

548

globalfail:

584

549

585

gnutls_certificate_free_credentials(mc->cred);

550

gnutls_certificate_free_credentials(mc.cred);

586

551

gnutls_global_deinit();

587

gnutls_dh_params_deinit(mc->dh_params);

552

gnutls_dh_params_deinit(mc.dh_params);

588

553

return -1;

589

554

}

590

555

591

__attribute__((nonnull, warn_unused_result))

592

static int init_gnutls_session(gnutls_session_t *session,

593

mandos_context *mc){

556

static int init_gnutls_session(gnutls_session_t *session){

594

557

int ret;

595

558

/* GnuTLS session creation */

596

559

do {

608

571

{

609

572

const char *err;

610

573

do {

611

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

574

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

612

575

if(quit_now){

613

576

gnutls_deinit(*session);

614

577

return -1;

625

588

626

589

do {

627

590

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

628

mc->cred);

591

mc.cred);

629

592

if(quit_now){

630

593

gnutls_deinit(*session);

631

594

return -1;

641

604

/* ignore client certificate if any. */

642

605

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

643

606

644

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

607

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

645

608

646

609

return 0;

647

610

}

650

613

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

651

614

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

652

615

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 delete_arg[] = "delete";

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 : delete_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

616

/* 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,

617

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

865

618

AvahiIfIndex if_index,

866

int af, mandos_context *mc){

619

int af){

867

620

int ret, tcp_sd = -1;

868

621

ssize_t sret;

869

struct sockaddr_storage to;

622

union {

623

struct sockaddr_in in;

624

struct sockaddr_in6 in6;

625

} to;

870

626

char *buffer = NULL;

871

627

char *decrypted_buffer = NULL;

872

628

size_t buffer_length = 0;

875

631

int retval = -1;

876

632

gnutls_session_t session;

877

633

int pf; /* Protocol family */

878

bool route_added = false;

879

634

880

635

errno = 0;

881

636

897

652

return -1;

898

653

}

899

654

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);

655

ret = init_gnutls_session(&session);

933

656

if(ret != 0){

934

657

return -1;

935

658

}

936

659

937

660

if(debug){

938

661

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

939

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

662

PRIu16 "\n", ip, port);

940

663

}

941

664

942

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

665

tcp_sd = socket(pf, SOCK_STREAM, 0);

943

666

if(tcp_sd < 0){

944

667

int e = errno;

945

668

perror_plus("socket");

954

677

955

678

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

956

679

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);

680

to.in6.sin6_family = (sa_family_t)af;

681

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

959

682

} 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);

683

to.in.sin_family = (sa_family_t)af;

684

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

962

685

}

963

686

if(ret < 0 ){

964

687

int e = errno;

973

696

goto mandos_end;

974

697

}

975

698

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)){

699

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

700

-Wconversion and

701

-Wunreachable-code */

702

703

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

704

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

705

-Wunreachable-code*/

979

706

if(if_index == AVAHI_IF_UNSPEC){

980

707

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

981

708

" incomplete without a network interface\n");

983

710

goto mandos_end;

984

711

}

985

712

/* Set the network interface number as scope */

986

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

713

to.in6.sin6_scope_id = (uint32_t)if_index;

987

714

}

988

715

} else {

989

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

716

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

717

-Wconversion and

718

-Wunreachable-code */

990

719

}

991

720

992

721

if(quit_now){

1000

729

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

1001

730

perror_plus("if_indextoname");

1002

731

} else {

1003

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

1004

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

732

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

733

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

1005

734

}

1006

735

} else {

1007

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

1008

ip, (uintmax_t)port);

736

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

737

ip, port);

1009

738

}

1010

739

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

1011

740

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;

741

const char *pcret;

742

if(af == AF_INET6){

743

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

744

sizeof(addrstr));

745

} else {

746

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

747

sizeof(addrstr));

748

}

749

if(pcret == NULL){

750

perror_plus("inet_ntop");

751

} else {

752

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

753

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

754

}

755

}

756

}

757

758

if(quit_now){

759

errno = EINTR;

760

goto mandos_end;

761

}

762

763

if(af == AF_INET6){

764

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

765

} else {

766

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

767

}

768

if(ret < 0){

769

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

770

int e = errno;

771

perror_plus("connect");

772

errno = e;

773

}

774

goto mandos_end;

775

}

776

777

if(quit_now){

778

errno = EINTR;

779

goto mandos_end;

1088

780

}

1089

781

1090

782

const char *out = mandos_protocol_version;

1126

818

goto mandos_end;

1127

819

}

1128

820

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);

821

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

822

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

1134

823

1135

824

if(quit_now){

1136

825

errno = EINTR;

1241

930

if(buffer_length > 0){

1242

931

ssize_t decrypted_buffer_size;

1243

932

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

1244

&decrypted_buffer, mc);

933

&decrypted_buffer);

1245

934

if(decrypted_buffer_size >= 0){

1246

935

1247

936

written = 0;

1273

962

1274

963

mandos_end:

1275

964

{

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

965

int e = errno;

1283

966

free(decrypted_buffer);

1284

967

free(buffer);

1301

984

return retval;

1302

985

}

1303

986

1304

__attribute__((nonnull))

1305

987

static void resolve_callback(AvahiSServiceResolver *r,

1306

988

AvahiIfIndex interface,

1307

989

AvahiProtocol proto,

1315

997

AVAHI_GCC_UNUSED AvahiStringList *txt,

1316

998

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1317

999

flags,

1318

void *mc){

1319

if(r == NULL){

1320

return;

1321

}

1000

AVAHI_GCC_UNUSED void* userdata){

1001

assert(r);

1322

1002

1323

1003

/* Called whenever a service has been resolved successfully or

1324

1004

timed out */

1325

1005

1326

1006

if(quit_now){

1327

avahi_s_service_resolver_free(r);

1328

1007

return;

1329

1008

}

1330

1009

1334

1013

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

1335

1014

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

1336

1015

domain,

1337

avahi_strerror(avahi_server_errno

1338

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

1016

avahi_strerror(avahi_server_errno(mc.server)));

1339

1017

break;

1340

1018

1341

1019

case AVAHI_RESOLVER_FOUND:

1347

1025

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

1348

1026

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

1349

1027

}

1350

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

1351

interface,

1352

avahi_proto_to_af(proto),

1353

mc);

1028

int ret = start_mandos_communication(ip, port, interface,

1029

avahi_proto_to_af(proto));

1354

1030

if(ret == 0){

1355

avahi_simple_poll_quit(simple_poll);

1031

avahi_simple_poll_quit(mc.simple_poll);

1356

1032

} 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

}

1033

ret = add_server(ip, port, interface,

1034

avahi_proto_to_af(proto));

1363

1035

}

1364

1036

}

1365

1037

}

1375

1047

const char *domain,

1376

1048

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1377

1049

flags,

1378

void *mc){

1379

if(b == NULL){

1380

return;

1381

}

1050

AVAHI_GCC_UNUSED void* userdata){

1051

assert(b);

1382

1052

1383

1053

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

1384

1054

is removed from the LAN */

1392

1062

case AVAHI_BROWSER_FAILURE:

1393

1063

1394

1064

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);

1065

avahi_strerror(avahi_server_errno(mc.server)));

1066

avahi_simple_poll_quit(mc.simple_poll);

1398

1067

return;

1399

1068

1400

1069

case AVAHI_BROWSER_NEW:

1403

1072

the callback function is called the Avahi server will free the

1404

1073

resolver for us. */

1405

1074

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)

1075

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

1076

name, type, domain, protocol, 0,

1077

resolve_callback, NULL) == NULL)

1410

1078

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

1411

1079

" %s\n", name,

1412

avahi_strerror(avahi_server_errno

1413

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

1080

avahi_strerror(avahi_server_errno(mc.server)));

1414

1081

break;

1415

1082

1416

1083

case AVAHI_BROWSER_REMOVE:

1435

1102

signal_received = sig;

1436

1103

int old_errno = errno;

1437

1104

/* set main loop to exit */

1438

if(simple_poll != NULL){

1439

avahi_simple_poll_quit(simple_poll);

1105

if(mc.simple_poll != NULL){

1106

avahi_simple_poll_quit(mc.simple_poll);

1440

1107

}

1441

1108

errno = old_errno;

1442

1109

}

1443

1110

1444

__attribute__((nonnull, warn_unused_result))

1445

1111

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

1446

1112

int ret;

1447

error_t ret_errno;

1448

1113

1449

1114

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

1450

1115

if(s < 0){

1451

ret_errno = errno;

1452

1116

perror_plus("socket");

1453

errno = ret_errno;

1454

1117

return false;

1455

1118

}

1456

1119

strcpy(ifr->ifr_name, ifname);

1457

1120

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1458

1121

if(ret == -1){

1459

1122

if(debug){

1460

ret_errno = errno;

1461

1123

perror_plus("ioctl SIOCGIFFLAGS");

1462

errno = ret_errno;

1463

1124

}

1464

1125

return false;

1465

1126

}

1466

1127

return true;

1467

1128

}

1468

1129

1469

__attribute__((nonnull, warn_unused_result))

1470

1130

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

1471

1131

1472

1132

/* Reject the loopback device */

1514

1174

* corresponds to an acceptable network device.

1515

1175

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

1516

1176

*/

1517

__attribute__((nonnull, warn_unused_result))

1518

1177

int good_interface(const struct dirent *if_entry){

1519

1178

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

1520

1179

return 0;

1536

1195

}

1537

1196

1538

1197

/*

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))

1198

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

1199

* corresponds to an acceptable network device which is up.

1200

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

1201

*/

1202

int up_interface(const struct dirent *if_entry){

1203

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

1204

return 0;

1205

}

1206

1207

struct ifreq ifr;

1208

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

1209

if(debug){

1210

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

1211

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

1212

}

1213

return 0;

1214

}

1215

1216

/* Reject down interfaces */

1217

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

1218

if(debug){

1219

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

1220

if_entry->d_name);

1221

}

1222

return 0;

1223

}

1224

1225

/* Reject non-running interfaces */

1226

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

1227

if(debug){

1228

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

1229

if_entry->d_name);

1230

}

1231

return 0;

1232

}

1233

1234

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

1235

return 0;

1236

}

1237

return 1;

1238

}

1239

1573

1240

int notdotentries(const struct dirent *direntry){

1574

1241

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

1575

1242

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

1582

1249

}

1583

1250

1584

1251

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

1585

__attribute__((nonnull, warn_unused_result))

1586

1252

int runnable_hook(const struct dirent *direntry){

1587

1253

int ret;

1588

1254

size_t sret;

1596

1262

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

1597

1263

"abcdefghijklmnopqrstuvwxyz"

1598

1264

"0123456789"

1599

"_.-");

1265

"_-");

1600

1266

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

1601

1267

/* Contains non-allowed characters */

1602

1268

if(debug){

1606

1272

return 0;

1607

1273

}

1608

1274

1609

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

1275

char *fullname = NULL;

1276

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

1277

if(ret < 0){

1278

perror_plus("asprintf");

1279

return 0;

1280

}

1281

1282

ret = stat(fullname, &st);

1610

1283

if(ret == -1){

1611

1284

if(debug){

1612

1285

perror_plus("Could not stat hook");

1636

1309

return 1;

1637

1310

}

1638

1311

1639

__attribute__((nonnull, warn_unused_result))

1640

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1641

mandos_context *mc){

1312

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1642

1313

int ret;

1643

1314

struct timespec now;

1644

1315

struct timespec waited_time;

1645

1316

intmax_t block_time;

1646

1317

1647

1318

while(true){

1648

if(mc->current_server == NULL){

1649

if(debug){

1319

if(mc.current_server == NULL){

1320

if (debug){

1650

1321

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

1651

1322

" No timeout!\n");

1652

1323

}

1653

1324

ret = avahi_simple_poll_iterate(s, -1);

1654

1325

} else {

1655

if(debug){

1326

if (debug){

1656

1327

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

1657

1328

" it, or wait\n");

1658

1329

}

1665

1336

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

1666

1337

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

1667

1338

waited_time.tv_sec = (now.tv_sec

1668

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

1339

- mc.current_server->last_seen.tv_sec);

1669

1340

waited_time.tv_nsec = (now.tv_nsec

1670

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

1341

- mc.current_server->last_seen.tv_nsec);

1671

1342

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

1672

1343

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

1673

1344

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

1675

1346

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

1676

1347

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

1677

1348

1678

if(debug){

1349

if (debug){

1679

1350

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

1680

1351

block_time);

1681

1352

}

1682

1353

1683

1354

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);

1355

ret = start_mandos_communication(mc.current_server->ip,

1356

mc.current_server->port,

1357

mc.current_server->if_index,

1358

mc.current_server->af);

1688

1359

if(ret == 0){

1689

avahi_simple_poll_quit(s);

1360

avahi_simple_poll_quit(mc.simple_poll);

1690

1361

return 0;

1691

1362

}

1692

1363

ret = clock_gettime(CLOCK_MONOTONIC,

1693

&mc->current_server->last_seen);

1364

&mc.current_server->last_seen);

1694

1365

if(ret == -1){

1695

1366

perror_plus("clock_gettime");

1696

1367

return -1;

1697

1368

}

1698

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

1369

mc.current_server = mc.current_server->next;

1699

1370

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

1700

1371

servers, but don't block */

1701

1372

}

1703

1374

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

1704

1375

}

1705

1376

if(ret != 0){

1706

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

1377

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

1707

1378

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

1708

1379

}

1709

1380

}

1710

1381

}

1711

1382

}

1712

1383

1713

__attribute__((nonnull))

1714

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

1384

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

1715

1385

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__ */

1386

struct dirent **direntries;

1387

struct dirent *direntry;

1388

int ret;

1389

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

1390

alphasort);

1744

1391

if(numhooks == -1){

1745

1392

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){

1393

} else {

1394

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

1395

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

1396

direntry = direntries[i];

1397

char *fullname = NULL;

1398

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

1399

if(ret < 0){

1807

1400

perror_plus("asprintf");

1808

_exit(EX_OSERR);

1809

}

1810

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

1811

if(ret == -1){

1401

continue;

1402

}

1403

if(debug){

1404

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

1405

direntry->d_name);

1406

}

1407

pid_t hook_pid = fork();

1408

if(hook_pid == 0){

1409

/* Child */

1410

/* Raise privileges */

1411

errno = 0;

1412

ret = seteuid(0);

1413

if(ret == -1){

1414

perror_plus("seteuid");

1415

}

1416

/* Raise privileges even more */

1417

errno = 0;

1418

ret = setuid(0);

1419

if(ret == -1){

1420

perror_plus("setuid");

1421

}

1422

/* Set group */

1423

errno = 0;

1424

ret = setgid(0);

1425

if(ret == -1){

1426

perror_plus("setgid");

1427

}

1428

/* Reset supplementary groups */

1429

errno = 0;

1430

ret = setgroups(0, NULL);

1431

if(ret == -1){

1432

perror_plus("setgroups");

1433

}

1434

dup2(devnull, STDIN_FILENO);

1435

close(devnull);

1436

dup2(STDERR_FILENO, STDOUT_FILENO);

1437

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

1438

if(ret == -1){

1439

perror_plus("setenv");

1440

_exit(EX_OSERR);

1441

}

1442

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

1443

if(ret == -1){

1444

perror_plus("setenv");

1445

_exit(EX_OSERR);

1446

}

1447

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

1448

if(ret == -1){

1449

perror_plus("setenv");

1450

_exit(EX_OSERR);

1451

}

1452

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

1453

if(ret == -1){

1454

perror_plus("setenv");

1455

_exit(EX_OSERR);

1456

}

1457

char *delaystring;

1458

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

1459

if(ret == -1){

1460

perror_plus("asprintf");

1461

_exit(EX_OSERR);

1462

}

1463

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

1464

if(ret == -1){

1465

free(delaystring);

1466

perror_plus("setenv");

1467

_exit(EX_OSERR);

1468

}

1812

1469

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;

1470

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

1471

perror_plus("execl");

1472

} else {

1473

int status;

1474

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

1475

perror_plus("waitpid");

1476

free(fullname);

1477

continue;

1478

}

1479

if(WIFEXITED(status)){

1480

if(WEXITSTATUS(status) != 0){

1481

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

1482

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

1483

WEXITSTATUS(status));

1484

free(fullname);

1485

continue;

1486

}

1487

} else if(WIFSIGNALED(status)){

1488

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

1489

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

1490

WTERMSIG(status));

1491

free(fullname);

1492

continue;

1493

} else {

1494

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

1495

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

1496

free(fullname);

1497

continue;

1498

}

1499

}

1500

free(fullname);

1501

if(debug){

1502

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

1503

direntry->d_name);

1504

}

1505

}

1506

close(devnull);

1507

}

1508

return true;

2103

1509

}

2104

1510

2105

1511

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

1512

AvahiSServiceBrowser *sb = NULL;

2111

error_t ret_errno;

1513

int error;

2112

1514

int ret;

2113

1515

intmax_t tmpmax;

2114

1516

char *tmp;

2115

1517

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;

1518

const char *interface = "";

1519

struct ifreq network;

1520

int sd = -1;

1521

bool take_down_interface = false;

1522

uid_t uid;

1523

gid_t gid;

1524

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

1525

bool tempdir_created = false;

2121

1526

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

2122

1527

const char *seckey = PATHDIR "/" SECKEY;

2123

1528

const char *pubkey = PATHDIR "/" PUBKEY;

2124

char *interfaces_hooks = NULL;

2125

1529

2126

1530

bool gnutls_initialized = false;

2127

1531

bool gpgme_initialized = false;

2189

1593

.group = 2 },

2190

1594

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

2191

1595

.arg = "SECONDS",

2192

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

1596

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

2193

1597

.group = 2 },

2194

1598

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

2195

1599

.arg = "DIR",

2218

1622

connect_to = arg;

2219

1623

break;

2220

1624

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

}

1625

interface = arg;

2226

1626

break;

2227

1627

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

2228

1628

seckey = arg;

2271

1671

argp_state_help(state, state->out_stream,

2272

1672

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

2273

1673

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

1674

fprintf_plus(state->out_stream,

1675

"Mandos plugin mandos-client: ");

2274

1676

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

2275

1677

exit(argp_err_exit_status);

2276

1678

break;

2300

1702

goto end;

2301

1703

}

2302

1704

}

2303

1705

2304

1706

{

2305

1707

/* Work around Debian bug #633582:

2306

1708

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

2307

1709

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");

1710

/* Re-raise priviliges */

1711

errno = 0;

1712

ret = seteuid(0);

1713

if(ret == -1){

1714

perror_plus("seteuid");

2313

1715

} else {

2314

1716

struct stat st;

2315

1717

2333

1735

TEMP_FAILURE_RETRY(close(seckey_fd));

2334

1736

}

2335

1737

}

2336

1738

2337

1739

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

2338

1740

int pubkey_fd = open(pubkey, O_RDONLY);

2339

1741

if(pubkey_fd == -1){

2354

1756

TEMP_FAILURE_RETRY(close(pubkey_fd));

2355

1757

}

2356

1758

}

2357

1759

2358

1760

/* 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;

1761

errno = 0;

1762

ret = seteuid(uid);

1763

if(ret == -1){

1764

perror_plus("seteuid");

2380

1765

}

2381

1766

}

2382

1767

}

2383

1768

2384

1769

/* Run network hooks */

2385

{

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);

1770

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

1771

goto end;

2397

1772

}

2398

1773

2399

1774

if(not debug){

2400

1775

avahi_set_log_function(empty_log);

2401

1776

}

2402

1777

1778

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

1779

struct dirent **direntries;

1780

/* First look for interfaces that are up */

1781

ret = scandir(sys_class_net, &direntries, up_interface,

1782

alphasort);

1783

if(ret == 0){

1784

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

1785

free(direntries);

1786

ret = scandir(sys_class_net, &direntries, good_interface,

1787

alphasort);

1788

}

1789

if(ret >= 1){

1790

/* Pick the first interface returned */

1791

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

1792

if(debug){

1793

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

1794

}

1795

if(interface == NULL){

1796

perror_plus("malloc");

1797

free(direntries);

1798

exitcode = EXIT_FAILURE;

1799

goto end;

1800

}

1801

free(direntries);

1802

} else {

1803

free(direntries);

1804

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

1805

exitcode = EXIT_FAILURE;

1806

goto end;

1807

}

1808

}

1809

2403

1810

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

2404

1811

from the signal handler */

2405

1812

/* Initialize the pseudo-RNG for Avahi */

2406

1813

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

2407

simple_poll = avahi_simple_poll_new();

2408

if(simple_poll == NULL){

1814

mc.simple_poll = avahi_simple_poll_new();

1815

if(mc.simple_poll == NULL){

2409

1816

fprintf_plus(stderr,

2410

1817

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

2411

1818

exitcode = EX_UNAVAILABLE;

2475

1882

}

2476

1883

}

2477

1884

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;

1885

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

1886

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

1887

if_index = (AvahiIfIndex) if_nametoindex(interface);

1888

if(if_index == 0){

1889

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

1890

exitcode = EX_UNAVAILABLE;

1891

goto end;

1892

}

1893

1894

if(quit_now){

1895

goto end;

1896

}

1897

1898

/* Re-raise priviliges */

1899

errno = 0;

1900

ret = seteuid(0);

1901

if(ret == -1){

1902

perror_plus("seteuid");

1903

}

1904

1905

#ifdef __linux__

1906

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1907

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

1908

ret = klogctl(8, NULL, 5);

1909

bool restore_loglevel = true;

1910

if(ret == -1){

1911

restore_loglevel = false;

1912

perror_plus("klogctl");

1913

}

1914

#endif /* __linux__ */

1915

1916

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1917

if(sd < 0){

1918

perror_plus("socket");

1919

exitcode = EX_OSERR;

1920

#ifdef __linux__

1921

if(restore_loglevel){

1922

ret = klogctl(7, NULL, 0);

1923

if(ret == -1){

1924

perror_plus("klogctl");

1925

}

1926

}

1927

#endif /* __linux__ */

1928

/* Lower privileges */

1929

errno = 0;

1930

ret = seteuid(uid);

1931

if(ret == -1){

1932

perror_plus("seteuid");

1933

}

1934

goto end;

1935

}

1936

strcpy(network.ifr_name, interface);

1937

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

1938

if(ret == -1){

1939

perror_plus("ioctl SIOCGIFFLAGS");

1940

#ifdef __linux__

1941

if(restore_loglevel){

1942

ret = klogctl(7, NULL, 0);

1943

if(ret == -1){

1944

perror_plus("klogctl");

1945

}

1946

}

1947

#endif /* __linux__ */

1948

exitcode = EX_OSERR;

1949

/* Lower privileges */

1950

errno = 0;

1951

ret = seteuid(uid);

1952

if(ret == -1){

1953

perror_plus("seteuid");

1954

}

1955

goto end;

1956

}

1957

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

1958

network.ifr_flags |= IFF_UP;

1959

take_down_interface = true;

1960

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

1961

if(ret == -1){

1962

take_down_interface = false;

1963

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1964

exitcode = EX_OSERR;

1965

#ifdef __linux__

1966

if(restore_loglevel){

1967

ret = klogctl(7, NULL, 0);

1968

if(ret == -1){

1969

perror_plus("klogctl");

2529

1970

}

2530

1971

}

1972

#endif /* __linux__ */

1973

/* Lower privileges */

1974

errno = 0;

1975

ret = seteuid(uid);

1976

if(ret == -1){

1977

perror_plus("seteuid");

1978

}

1979

goto end;

1980

}

1981

}

1982

/* Sleep checking until interface is running.

1983

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

1984

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

1985

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

1986

if(ret == -1){

1987

perror_plus("ioctl SIOCGIFFLAGS");

1988

} else if(network.ifr_flags & IFF_RUNNING){

2531

1989

break;

2532

1990

}

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);

1991

struct timespec sleeptime = { .tv_nsec = 250000000 };

1992

ret = nanosleep(&sleeptime, NULL);

1993

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

1994

perror_plus("nanosleep");

1995

}

1996

}

1997

if(not take_down_interface){

1998

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

1999

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

2000

if(ret == -1){

2001

perror_plus("close");

2002

}

2003

}

2004

#ifdef __linux__

2005

if(restore_loglevel){

2006

/* Restores kernel loglevel to default */

2007

ret = klogctl(7, NULL, 0);

2008

if(ret == -1){

2009

perror_plus("klogctl");

2010

}

2011

}

2012

#endif /* __linux__ */

2013

/* Lower privileges */

2014

errno = 0;

2015

/* Lower privileges */

2016

ret = seteuid(uid);

2017

if(ret == -1){

2018

perror_plus("seteuid");

2019

}

2560

2020

}

2561

2021

2562

2022

if(quit_now){

2563

2023

goto end;

2564

2024

}

2565

2025

2566

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

2026

ret = init_gnutls_global(pubkey, seckey);

2567

2027

if(ret == -1){

2568

2028

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

2569

2029

exitcode = EX_UNAVAILABLE;

2576

2036

goto end;

2577

2037

}

2578

2038

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){

2039

if(mkdtemp(tempdir) == NULL){

2589

2040

perror_plus("mkdtemp");

2590

2041

goto end;

2591

2042

}

2043

tempdir_created = true;

2592

2044

2593

2045

if(quit_now){

2594

2046

goto end;

2595

2047

}

2596

2048

2597

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

2049

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

2598

2050

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

2599

2051

exitcode = EX_UNAVAILABLE;

2600

2052

goto end;

2610

2062

/* Connect directly, do not use Zeroconf */

2611

2063

/* (Mainly meant for debugging) */

2612

2064

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

2613

2614

2065

if(address == NULL){

2615

2066

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

2616

2067

exitcode = EX_USAGE;

2621

2072

goto end;

2622

2073

}

2623

2074

2624

in_port_t port;

2075

uint16_t port;

2625

2076

errno = 0;

2626

2077

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

2627

2078

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

2628

or tmpmax != (in_port_t)tmpmax){

2079

or tmpmax != (uint16_t)tmpmax){

2629

2080

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

2630

2081

exitcode = EX_USAGE;

2631

2082

goto end;

2632

2083

}

2633

2084

2634

2085

if(quit_now){

2635

2086

goto end;

2636

2087

}

2637

2088

2638

port = (in_port_t)tmpmax;

2089

port = (uint16_t)tmpmax;

2639

2090

*address = '\0';

2640

2091

/* Colon in address indicates IPv6 */

2641

2092

int af;

2657

2108

}

2658

2109

2659

2110

while(not quit_now){

2660

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

2661

&mc);

2111

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

2662

2112

if(quit_now or ret == 0){

2663

2113

break;

2664

2114

}

2666

2116

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

2667

2117

(int)retry_interval);

2668

2118

}

2669

sleep((unsigned int)retry_interval);

2119

sleep((int)retry_interval);

2670

2120

}

2671

2121

2672

if(not quit_now){

2122

if (not quit_now){

2673

2123

exitcode = EXIT_SUCCESS;

2674

2124

}

2675

2125

2690

2140

config.publish_domain = 0;

2691

2141

2692

2142

/* Allocate a new server */

2693

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2694

&config, NULL, NULL, &ret_errno);

2143

mc.server = avahi_server_new(avahi_simple_poll_get

2144

(mc.simple_poll), &config, NULL,

2145

NULL, &error);

2695

2146

2696

2147

/* Free the Avahi configuration data */

2697

2148

avahi_server_config_free(&config);

2700

2151

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

2701

2152

if(mc.server == NULL){

2702

2153

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

2703

avahi_strerror(ret_errno));

2154

avahi_strerror(error));

2704

2155

exitcode = EX_UNAVAILABLE;

2705

2156

goto end;

2706

2157

}

2712

2163

/* Create the Avahi service browser */

2713

2164

sb = avahi_s_service_browser_new(mc.server, if_index,

2714

2165

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2715

NULL, 0, browse_callback,

2716

(void *)&mc);

2166

NULL, 0, browse_callback, NULL);

2717

2167

if(sb == NULL){

2718

2168

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

2719

2169

avahi_strerror(avahi_server_errno(mc.server)));

2730

2180

if(debug){

2731

2181

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

2732

2182

}

2733

2734

ret = avahi_loop_with_timeout(simple_poll,

2735

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

2183

2184

ret = avahi_loop_with_timeout(mc.simple_poll,

2185

(int)(retry_interval * 1000));

2736

2186

if(debug){

2737

2187

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

2738

2188

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

2745

2195

}

2746

2196

2747

2197

/* Cleanup things */

2748

free(mc.interfaces);

2749

2750

2198

if(sb != NULL)

2751

2199

avahi_s_service_browser_free(sb);

2752

2200

2753

2201

if(mc.server != NULL)

2754

2202

avahi_server_free(mc.server);

2755

2203

2756

if(simple_poll != NULL)

2757

avahi_simple_poll_free(simple_poll);

2204

if(mc.simple_poll != NULL)

2205

avahi_simple_poll_free(mc.simple_poll);

2758

2206

2759

2207

if(gnutls_initialized){

2760

2208

gnutls_certificate_free_credentials(mc.cred);

2772

2220

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

2773

2221

while(mc.current_server != NULL){

2774

2222

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

2223

free(mc.current_server);

2784

2224

mc.current_server = next;

2785

2225

}

2786

2226

}

2787

2227

2788

/* Re-raise privileges */

2228

/* Run network hooks */

2229

run_network_hooks("stop", interface, delay);

2230

2231

/* Re-raise priviliges */

2789

2232

{

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

}

2233

errno = 0;

2234

ret = seteuid(0);

2235

if(ret == -1){

2236

perror_plus("seteuid");

2817

2237

}

2818

2238

2819

ret_errno = lower_privileges_permanently();

2820

if(ret_errno != 0){

2821

errno = ret_errno;

2822

perror_plus("Failed to lower privileges permanently");

2239

/* Take down the network interface */

2240

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

2241

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

2242

if(ret == -1){

2243

perror_plus("ioctl SIOCGIFFLAGS");

2244

} else if(network.ifr_flags & IFF_UP){

2245

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

2246

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

2247

if(ret == -1){

2248

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2249

}

2250

}

2251

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

2252

if(ret == -1){

2253

perror_plus("close");

2254

}

2823

2255

}

2824

2256

}

2825

2826

free(interfaces_to_take_down);

2827

free(interfaces_hooks);

2257

/* Lower privileges permanently */

2258

errno = 0;

2259

ret = setuid(uid);

2260

if(ret == -1){

2261

perror_plus("setuid");

2262

}

2828

2263

2829

2264

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

2830

if(tempdir != NULL){

2265

if(tempdir_created){

2831

2266

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

}

2267

struct dirent *direntry = NULL;

2268

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

2269

alphasort);

2270

if (numentries > 0){

2271

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

2272

direntry = direntries[i];

2273

char *fullname = NULL;

2274

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

2275

direntry->d_name);

2276

if(ret < 0){

2277

perror_plus("asprintf");

2278

continue;

2279

}

2280

ret = remove(fullname);

2281

if(ret == -1){

2282

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

2283

strerror(errno));

2284

}

2285

free(fullname);

2871

2286

}

2872

TEMP_FAILURE_RETRY(close(tempdir_fd));

2287

}

2288

2289

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

2290

free(direntries);

2291

if (numentries == -1){

2292

perror_plus("scandir");

2293

}

2294

ret = rmdir(tempdir);

2295

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

2296

perror_plus("rmdir");

2873

2297

}

2874

2298

}

2875

2299