/mandos/trunk : revision 577

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(),

59

getnameinfo() */

60

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

58

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,

64

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(),

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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;

185

177

perror(print_text);

186

178

}

187

179

188

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

180

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

189

181

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

190

182

va_list ap;

191

183

va_start (ap, format);

192

184

193

185

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

194

186

program_invocation_short_name));

195

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

187

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

196

188

}

197

189

198

190

/*

200

192

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

201

193

* "buffer_length" is how much is already used.

202

194

*/

203

__attribute__((nonnull, warn_unused_result))

204

195

size_t incbuffer(char **buffer, size_t buffer_length,

205

196

size_t buffer_capacity){

206

197

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;

198

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

199

if(buffer == NULL){

213

200

return 0;

214

201

}

215

*buffer = new_buf;

216

202

buffer_capacity += BUFFER_SIZE;

217

203

}

218

204

return buffer_capacity;

219

205

}

220

206

221

207

/* 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){

208

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

209

int af){

225

210

int ret;

226

211

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

227

212

if(new_server == NULL){

234

219

.af = af };

235

220

if(new_server->ip == NULL){

236

221

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

222

return false;

253

223

}

254

224

/* Special case of first server */

255

if(*current_server == NULL){

225

if (mc.current_server == NULL){

256

226

new_server->next = new_server;

257

227

new_server->prev = new_server;

258

*current_server = new_server;

228

mc.current_server = new_server;

229

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

259

230

} else {

260

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

261

new_server->next = *current_server;

262

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

231

new_server->next = mc.current_server;

232

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

263

233

new_server->prev->next = new_server;

264

(*current_server)->prev = new_server;

234

mc.current_server->prev = new_server;

235

}

236

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

237

if(ret == -1){

238

perror_plus("clock_gettime");

239

return false;

265

240

}

266

241

return true;

267

242

}

269

244

/*

270

245

* Initialize GPGME.

271

246

*/

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){

247

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

248

const char *tempdir){

277

249

gpgme_error_t rc;

278

250

gpgme_engine_info_t engine_info;

279

251

252

280

253

/*

281

254

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

282

255

*/

283

bool import_key(const char * const filename){

256

bool import_key(const char *filename){

284

257

int ret;

285

258

int fd;

286

259

gpgme_data_t pgp_data;

298

271

return false;

299

272

}

300

273

301

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

274

rc = gpgme_op_import(mc.ctx, pgp_data);

302

275

if(rc != GPG_ERR_NO_ERROR){

303

276

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

304

277

gpgme_strsource(rc), gpgme_strerror(rc));

348

321

}

349

322

350

323

/* Create new GPGME "context" */

351

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

324

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

352

325

if(rc != GPG_ERR_NO_ERROR){

353

326

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

354

327

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

367

340

* Decrypt OpenPGP data.

368

341

* Returns -1 on error

369

342

*/

370

__attribute__((nonnull, warn_unused_result))

371

343

static ssize_t pgp_packet_decrypt(const char *cryptotext,

372

344

size_t crypto_size,

373

char **plaintext,

374

mandos_context *mc){

345

char **plaintext){

375

346

gpgme_data_t dh_crypto, dh_plain;

376

347

gpgme_error_t rc;

377

348

ssize_t ret;

403

374

404

375

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

405

376

data buffer */

406

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

377

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

407

378

if(rc != GPG_ERR_NO_ERROR){

408

379

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

409

380

gpgme_strsource(rc), gpgme_strerror(rc));

410

381

plaintext_length = -1;

411

382

if(debug){

412

383

gpgme_decrypt_result_t result;

413

result = gpgme_op_decrypt_result(mc->ctx);

384

result = gpgme_op_decrypt_result(mc.ctx);

414

385

if(result == NULL){

415

386

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

416

387

} else {

493

464

return plaintext_length;

494

465

}

495

466

496

__attribute__((warn_unused_result))

497

static const char *safer_gnutls_strerror(int value){

498

const char *ret = gnutls_strerror(value);

467

static const char * safer_gnutls_strerror(int value){

468

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

469

-Wunreachable-code */

499

470

if(ret == NULL)

500

471

ret = "(unknown)";

501

472

return ret;

502

473

}

503

474

504

475

/* GnuTLS log function callback */

505

__attribute__((nonnull))

506

476

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

507

477

const char* string){

508

478

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

509

479

}

510

480

511

__attribute__((nonnull, warn_unused_result))

512

481

static int init_gnutls_global(const char *pubkeyfilename,

513

const char *seckeyfilename,

514

mandos_context *mc){

482

const char *seckeyfilename){

515

483

int ret;

516

484

517

485

if(debug){

534

502

}

535

503

536

504

/* OpenPGP credentials */

537

ret = gnutls_certificate_allocate_credentials(&mc->cred);

505

ret = gnutls_certificate_allocate_credentials(&mc.cred);

538

506

if(ret != GNUTLS_E_SUCCESS){

539

507

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

540

508

safer_gnutls_strerror(ret));

550

518

}

551

519

552

520

ret = gnutls_certificate_set_openpgp_key_file

553

(mc->cred, pubkeyfilename, seckeyfilename,

521

(mc.cred, pubkeyfilename, seckeyfilename,

554

522

GNUTLS_OPENPGP_FMT_BASE64);

555

523

if(ret != GNUTLS_E_SUCCESS){

556

524

fprintf_plus(stderr,

562

530

}

563

531

564

532

/* GnuTLS server initialization */

565

ret = gnutls_dh_params_init(&mc->dh_params);

533

ret = gnutls_dh_params_init(&mc.dh_params);

566

534

if(ret != GNUTLS_E_SUCCESS){

567

535

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

568

536

" initialization: %s\n",

569

537

safer_gnutls_strerror(ret));

570

538

goto globalfail;

571

539

}

572

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

540

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

573

541

if(ret != GNUTLS_E_SUCCESS){

574

542

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

575

543

safer_gnutls_strerror(ret));

576

544

goto globalfail;

577

545

}

578

546

579

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

547

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

580

548

581

549

return 0;

582

550

583

551

globalfail:

584

552

585

gnutls_certificate_free_credentials(mc->cred);

553

gnutls_certificate_free_credentials(mc.cred);

586

554

gnutls_global_deinit();

587

gnutls_dh_params_deinit(mc->dh_params);

555

gnutls_dh_params_deinit(mc.dh_params);

588

556

return -1;

589

557

}

590

558

591

__attribute__((nonnull, warn_unused_result))

592

static int init_gnutls_session(gnutls_session_t *session,

593

mandos_context *mc){

559

static int init_gnutls_session(gnutls_session_t *session){

594

560

int ret;

595

561

/* GnuTLS session creation */

596

562

do {

608

574

{

609

575

const char *err;

610

576

do {

611

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

577

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

612

578

if(quit_now){

613

579

gnutls_deinit(*session);

614

580

return -1;

625

591

626

592

do {

627

593

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

628

mc->cred);

594

mc.cred);

629

595

if(quit_now){

630

596

gnutls_deinit(*session);

631

597

return -1;

641

607

/* ignore client certificate if any. */

642

608

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

643

609

644

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

610

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

645

611

646

612

return 0;

647

613

}

650

616

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

651

617

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

652

618

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 delete_local_route() */

706

__attribute__((nonnull, warn_unused_result))

707

static bool add_delete_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 debug_flag[] = "--debug";

715

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

716

if(pluginhelperdir == NULL){

717

if(debug){

718

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

719

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

720

}

721

return false;

722

}

723

724

char interface[IF_NAMESIZE];

725

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

726

perror_plus("if_indextoname");

727

return false;

728

}

729

730

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

731

if(devnull == -1){

732

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

733

return false;

734

}

735

pid_t pid = fork();

736

if(pid == 0){

737

/* Child */

738

/* Raise privileges */

739

errno = raise_privileges_permanently();

740

if(errno != 0){

741

perror_plus("Failed to raise privileges");

742

/* _exit(EX_NOPERM); */

743

} else {

744

/* Set group */

745

errno = 0;

746

ret = setgid(0);

747

if(ret == -1){

748

perror_plus("setgid");

749

_exit(EX_NOPERM);

750

}

751

/* Reset supplementary groups */

752

errno = 0;

753

ret = setgroups(0, NULL);

754

if(ret == -1){

755

perror_plus("setgroups");

756

_exit(EX_NOPERM);

757

}

758

}

759

ret = dup2(devnull, STDIN_FILENO);

760

if(ret == -1){

761

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

762

_exit(EX_OSERR);

763

}

764

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

765

if(ret == -1){

766

perror_plus("close");

767

_exit(EX_OSERR);

768

}

769

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

770

if(ret == -1){

771

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

772

_exit(EX_OSERR);

773

}

774

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

775

O_RDONLY

776

| O_DIRECTORY

777

| O_PATH

778

| O_CLOEXEC));

779

if(helperdir_fd == -1){

780

perror_plus("open");

781

_exit(EX_UNAVAILABLE);

782

}

783

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

784

helper, O_RDONLY));

785

if(helper_fd == -1){

786

perror_plus("openat");

787

_exit(EX_UNAVAILABLE);

788

}

789

TEMP_FAILURE_RETRY(close(helperdir_fd));

790

#ifdef __GNUC__

791

#pragma GCC diagnostic push

792

#pragma GCC diagnostic ignored "-Wcast-qual"

793

#endif

794

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

795

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

796

interface, debug ? debug_flag : NULL, NULL },

797

environ) == -1){

798

#ifdef __GNUC__

799

#pragma GCC diagnostic pop

800

#endif

801

perror_plus("fexecve");

802

_exit(EXIT_FAILURE);

803

}

804

}

805

if(pid == -1){

806

perror_plus("fork");

807

return false;

808

}

809

int status;

810

pid_t pret = -1;

811

errno = 0;

812

do {

813

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

814

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

815

int errno_raising = 0;

816

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

817

errno_raising = errno;

818

perror_plus("Failed to raise privileges in order to"

819

" kill helper program");

820

}

821

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

822

perror_plus("kill");

823

}

824

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

825

perror_plus("Failed to lower privileges after killing"

826

" helper program");

827

}

828

return false;

829

}

830

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

831

if(pret == -1){

832

perror_plus("waitpid");

833

return false;

834

}

835

if(WIFEXITED(status)){

836

if(WEXITSTATUS(status) != 0){

837

fprintf_plus(stderr, "Error: iprouteadddel exited"

838

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

839

return false;

840

}

841

return true;

842

}

843

if(WIFSIGNALED(status)){

844

fprintf_plus(stderr, "Error: iprouteadddel died by"

845

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

846

return false;

847

}

848

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

849

return false;

850

}

851

852

__attribute__((nonnull, warn_unused_result))

853

static bool add_local_route(const char *address,

854

AvahiIfIndex if_index){

855

if(debug){

856

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

857

}

858

return add_delete_local_route(true, address, if_index);

859

}

860

861

__attribute__((nonnull, warn_unused_result))

862

static bool delete_local_route(const char *address,

863

AvahiIfIndex if_index){

864

if(debug){

865

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

866

}

867

return add_delete_local_route(false, address, if_index);

868

}

869

870

619

/* Called when a Mandos server is found */

871

__attribute__((nonnull, warn_unused_result))

872

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

620

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

873

621

AvahiIfIndex if_index,

874

int af, mandos_context *mc){

622

int af){

875

623

int ret, tcp_sd = -1;

876

624

ssize_t sret;

877

struct sockaddr_storage to;

625

union {

626

struct sockaddr_in in;

627

struct sockaddr_in6 in6;

628

} to;

878

629

char *buffer = NULL;

879

630

char *decrypted_buffer = NULL;

880

631

size_t buffer_length = 0;

883

634

int retval = -1;

884

635

gnutls_session_t session;

885

636

int pf; /* Protocol family */

886

bool route_added = false;

887

637

888

638

errno = 0;

889

639

905

655

return -1;

906

656

}

907

657

908

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

909

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

910

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

911

bool match = false;

912

{

913

char *interface = NULL;

914

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

915

interface))){

916

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

917

match = true;

918

break;

919

}

920

}

921

}

922

if(not match){

923

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

924

connect to the server */

925

if(debug){

926

char interface[IF_NAMESIZE];

927

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

928

perror_plus("if_indextoname");

929

} else {

930

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

931

" \"%s\"\n",

932

if_indextoname((unsigned int)if_index,

933

interface));

934

}

935

}

936

return -1;

937

}

938

}

939

940

ret = init_gnutls_session(&session, mc);

658

ret = init_gnutls_session(&session);

941

659

if(ret != 0){

942

660

return -1;

943

661

}

944

662

945

663

if(debug){

946

664

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

947

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

665

PRIu16 "\n", ip, port);

948

666

}

949

667

950

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

668

tcp_sd = socket(pf, SOCK_STREAM, 0);

951

669

if(tcp_sd < 0){

952

670

int e = errno;

953

671

perror_plus("socket");

962

680

963

681

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

964

682

if(af == AF_INET6){

965

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

966

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

683

to.in6.sin6_family = (sa_family_t)af;

684

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

967

685

} else { /* IPv4 */

968

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

969

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

686

to.in.sin_family = (sa_family_t)af;

687

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

970

688

}

971

689

if(ret < 0 ){

972

690

int e = errno;

981

699

goto mandos_end;

982

700

}

983

701

if(af == AF_INET6){

984

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

985

if(IN6_IS_ADDR_LINKLOCAL

986

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

702

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

703

-Wconversion and

704

-Wunreachable-code */

705

706

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

707

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

708

-Wunreachable-code*/

987

709

if(if_index == AVAHI_IF_UNSPEC){

988

710

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

989

711

" incomplete without a network interface\n");

991

713

goto mandos_end;

992

714

}

993

715

/* Set the network interface number as scope */

994

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

716

to.in6.sin6_scope_id = (uint32_t)if_index;

995

717

}

996

718

} else {

997

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

719

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

720

-Wconversion and

721

-Wunreachable-code */

998

722

}

999

723

1000

724

if(quit_now){

1008

732

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

1009

733

perror_plus("if_indextoname");

1010

734

} else {

1011

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

1012

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

735

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

736

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

1013

737

}

1014

738

} else {

1015

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

1016

ip, (uintmax_t)port);

739

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

740

ip, port);

1017

741

}

1018

742

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

1019

743

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

1020

if(af == AF_INET6){

1021

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

1022

sizeof(struct sockaddr_in6),

1023

addrstr, sizeof(addrstr), NULL, 0,

1024

NI_NUMERICHOST);

1025

} else {

1026

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

1027

sizeof(struct sockaddr_in),

1028

addrstr, sizeof(addrstr), NULL, 0,

1029

NI_NUMERICHOST);

1030

}

1031

if(ret == EAI_SYSTEM){

1032

perror_plus("getnameinfo");

1033

} else if(ret != 0) {

1034

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

1035

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

1036

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

1037

}

1038

}

1039

1040

if(quit_now){

1041

errno = EINTR;

1042

goto mandos_end;

1043

}

1044

1045

while(true){

1046

if(af == AF_INET6){

1047

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

1048

sizeof(struct sockaddr_in6));

1049

} else {

1050

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

1051

sizeof(struct sockaddr_in));

1052

}

1053

if(ret < 0){

1054

if(errno == ENETUNREACH

1055

and if_index != AVAHI_IF_UNSPEC

1056

and connect_to == NULL

1057

and not route_added and

1058

((af == AF_INET6 and not

1059

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1060

&to)->sin6_addr)))

1061

or (af == AF_INET and

1062

/* Not a a IPv4LL address */

1063

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

1064

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

1065

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

1066

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

1067

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

1068

connect to a Mandos server announced by Avahi on a server

1069

host with a global address. Work around this by retrying

1070

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

1071

1072

Avahi bug reference:

1073

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

1074

https://bugs.debian.org/587961

1075

*/

1076

if(debug){

1077

fprintf_plus(stderr, "Mandos server unreachable, trying"

1078

" direct route\n");

1079

}

1080

int e = errno;

1081

route_added = add_local_route(ip, if_index);

1082

if(route_added){

1083

continue;

1084

}

1085

errno = e;

1086

}

1087

if(errno != ECONNREFUSED or debug){

1088

int e = errno;

1089

perror_plus("connect");

1090

errno = e;

1091

}

1092

goto mandos_end;

1093

}

1094

1095

if(quit_now){

1096

errno = EINTR;

1097

goto mandos_end;

1098

}

1099

break;

744

const char *pcret;

745

if(af == AF_INET6){

746

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

747

sizeof(addrstr));

748

} else {

749

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

750

sizeof(addrstr));

751

}

752

if(pcret == NULL){

753

perror_plus("inet_ntop");

754

} else {

755

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

756

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

757

}

758

}

759

}

760

761

if(quit_now){

762

errno = EINTR;

763

goto mandos_end;

764

}

765

766

if(af == AF_INET6){

767

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

768

} else {

769

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

770

}

771

if(ret < 0){

772

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

773

int e = errno;

774

perror_plus("connect");

775

errno = e;

776

}

777

goto mandos_end;

778

}

779

780

if(quit_now){

781

errno = EINTR;

782

goto mandos_end;

1100

783

}

1101

784

1102

785

const char *out = mandos_protocol_version;

1138

821

goto mandos_end;

1139

822

}

1140

823

1141

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

1142

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

1143

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

1144

gnutls_transport_set_ptr(session,

1145

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

824

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

825

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

1146

826

1147

827

if(quit_now){

1148

828

errno = EINTR;

1253

933

if(buffer_length > 0){

1254

934

ssize_t decrypted_buffer_size;

1255

935

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

1256

&decrypted_buffer, mc);

936

&decrypted_buffer);

1257

937

if(decrypted_buffer_size >= 0){

1258

938

1259

939

written = 0;

1285

965

1286

966

mandos_end:

1287

967

{

1288

if(route_added){

1289

if(not delete_local_route(ip, if_index)){

1290

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

1291

" interface %d", ip, if_index);

1292

}

1293

}

1294

968

int e = errno;

1295

969

free(decrypted_buffer);

1296

970

free(buffer);

1313

987

return retval;

1314

988

}

1315

989

1316

__attribute__((nonnull))

1317

990

static void resolve_callback(AvahiSServiceResolver *r,

1318

991

AvahiIfIndex interface,

1319

992

AvahiProtocol proto,

1327

1000

AVAHI_GCC_UNUSED AvahiStringList *txt,

1328

1001

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1329

1002

flags,

1330

void *mc){

1331

if(r == NULL){

1332

return;

1333

}

1003

AVAHI_GCC_UNUSED void* userdata){

1004

assert(r);

1334

1005

1335

1006

/* Called whenever a service has been resolved successfully or

1336

1007

timed out */

1337

1008

1338

1009

if(quit_now){

1339

avahi_s_service_resolver_free(r);

1340

1010

return;

1341

1011

}

1342

1012

1346

1016

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

1347

1017

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

1348

1018

domain,

1349

avahi_strerror(avahi_server_errno

1350

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

1019

avahi_strerror(avahi_server_errno(mc.server)));

1351

1020

break;

1352

1021

1353

1022

case AVAHI_RESOLVER_FOUND:

1359

1028

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

1360

1029

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

1361

1030

}

1362

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

1363

interface,

1364

avahi_proto_to_af(proto),

1365

mc);

1031

int ret = start_mandos_communication(ip, port, interface,

1032

avahi_proto_to_af(proto));

1366

1033

if(ret == 0){

1367

avahi_simple_poll_quit(simple_poll);

1034

avahi_simple_poll_quit(mc.simple_poll);

1368

1035

} else {

1369

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

1370

avahi_proto_to_af(proto),

1371

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

1036

if(not add_server(ip, port, interface,

1037

avahi_proto_to_af(proto))){

1372

1038

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

1373

1039

" list\n", name);

1374

1040

}

1387

1053

const char *domain,

1388

1054

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1389

1055

flags,

1390

void *mc){

1391

if(b == NULL){

1392

return;

1393

}

1056

AVAHI_GCC_UNUSED void* userdata){

1057

assert(b);

1394

1058

1395

1059

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

1396

1060

is removed from the LAN */

1404

1068

case AVAHI_BROWSER_FAILURE:

1405

1069

1406

1070

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

1407

avahi_strerror(avahi_server_errno

1408

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

1409

avahi_simple_poll_quit(simple_poll);

1071

avahi_strerror(avahi_server_errno(mc.server)));

1072

avahi_simple_poll_quit(mc.simple_poll);

1410

1073

return;

1411

1074

1412

1075

case AVAHI_BROWSER_NEW:

1415

1078

the callback function is called the Avahi server will free the

1416

1079

resolver for us. */

1417

1080

1418

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

1419

interface, protocol, name, type,

1420

domain, protocol, 0,

1421

resolve_callback, mc) == NULL)

1081

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

1082

name, type, domain, protocol, 0,

1083

resolve_callback, NULL) == NULL)

1422

1084

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

1423

1085

" %s\n", name,

1424

avahi_strerror(avahi_server_errno

1425

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

1086

avahi_strerror(avahi_server_errno(mc.server)));

1426

1087

break;

1427

1088

1428

1089

case AVAHI_BROWSER_REMOVE:

1447

1108

signal_received = sig;

1448

1109

int old_errno = errno;

1449

1110

/* set main loop to exit */

1450

if(simple_poll != NULL){

1451

avahi_simple_poll_quit(simple_poll);

1111

if(mc.simple_poll != NULL){

1112

avahi_simple_poll_quit(mc.simple_poll);

1452

1113

}

1453

1114

errno = old_errno;

1454

1115

}

1455

1116

1456

__attribute__((nonnull, warn_unused_result))

1457

1117

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

1458

1118

int ret;

1459

error_t ret_errno;

1460

1119

1461

1120

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

1462

1121

if(s < 0){

1463

ret_errno = errno;

1464

1122

perror_plus("socket");

1465

errno = ret_errno;

1466

1123

return false;

1467

1124

}

1468

1125

strcpy(ifr->ifr_name, ifname);

1469

1126

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1470

1127

if(ret == -1){

1471

1128

if(debug){

1472

ret_errno = errno;

1473

1129

perror_plus("ioctl SIOCGIFFLAGS");

1474

errno = ret_errno;

1475

1130

}

1476

1131

return false;

1477

1132

}

1478

1133

return true;

1479

1134

}

1480

1135

1481

__attribute__((nonnull, warn_unused_result))

1482

1136

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

1483

1137

1484

1138

/* Reject the loopback device */

1526

1180

* corresponds to an acceptable network device.

1527

1181

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

1528

1182

*/

1529

__attribute__((nonnull, warn_unused_result))

1530

1183

int good_interface(const struct dirent *if_entry){

1531

1184

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

1532

1185

return 0;

1548

1201

}

1549

1202

1550

1203

/*

1551

* This function determines if a network interface is up.

1552

*/

1553

__attribute__((nonnull, warn_unused_result))

1554

bool interface_is_up(const char *interface){

1555

struct ifreq ifr;

1556

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

1557

if(debug){

1558

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

1559

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

1560

}

1561

return false;

1562

}

1563

1564

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

1565

}

1566

1567

/*

1568

* This function determines if a network interface is running

1569

*/

1570

__attribute__((nonnull, warn_unused_result))

1571

bool interface_is_running(const char *interface){

1572

struct ifreq ifr;

1573

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

1574

if(debug){

1575

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

1576

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

1577

}

1578

return false;

1579

}

1580

1581

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

1582

}

1583

1584

__attribute__((nonnull, pure, warn_unused_result))

1204

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

1205

* corresponds to an acceptable network device which is up.

1206

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

1207

*/

1208

int up_interface(const struct dirent *if_entry){

1209

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

1210

return 0;

1211

}

1212

1213

struct ifreq ifr;

1214

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

1215

if(debug){

1216

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

1217

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

1218

}

1219

return 0;

1220

}

1221

1222

/* Reject down interfaces */

1223

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

1224

if(debug){

1225

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

1226

if_entry->d_name);

1227

}

1228

return 0;

1229

}

1230

1231

/* Reject non-running interfaces */

1232

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

1233

if(debug){

1234

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

1235

if_entry->d_name);

1236

}

1237

return 0;

1238

}

1239

1240

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

1241

return 0;

1242

}

1243

return 1;

1244

}

1245

1585

1246

int notdotentries(const struct dirent *direntry){

1586

1247

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

1587

1248

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

1594

1255

}

1595

1256

1596

1257

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

1597

__attribute__((nonnull, warn_unused_result))

1598

1258

int runnable_hook(const struct dirent *direntry){

1599

1259

int ret;

1600

1260

size_t sret;

1608

1268

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

1609

1269

"abcdefghijklmnopqrstuvwxyz"

1610

1270

"0123456789"

1611

"_.-");

1271

"_-");

1612

1272

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

1613

1273

/* Contains non-allowed characters */

1614

1274

if(debug){

1618

1278

return 0;

1619

1279

}

1620

1280

1621

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

1281

char *fullname = NULL;

1282

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

1283

if(ret < 0){

1284

perror_plus("asprintf");

1285

return 0;

1286

}

1287

1288

ret = stat(fullname, &st);

1622

1289

if(ret == -1){

1623

1290

if(debug){

1624

1291

perror_plus("Could not stat hook");

1648

1315

return 1;

1649

1316

}

1650

1317

1651

__attribute__((nonnull, warn_unused_result))

1652

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1653

mandos_context *mc){

1318

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1654

1319

int ret;

1655

1320

struct timespec now;

1656

1321

struct timespec waited_time;

1657

1322

intmax_t block_time;

1658

1323

1659

1324

while(true){

1660

if(mc->current_server == NULL){

1661

if(debug){

1325

if(mc.current_server == NULL){

1326

if (debug){

1662

1327

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

1663

1328

" No timeout!\n");

1664

1329

}

1665

1330

ret = avahi_simple_poll_iterate(s, -1);

1666

1331

} else {

1667

if(debug){

1332

if (debug){

1668

1333

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

1669

1334

" it, or wait\n");

1670

1335

}

1677

1342

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

1678

1343

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

1679

1344

waited_time.tv_sec = (now.tv_sec

1680

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

1345

- mc.current_server->last_seen.tv_sec);

1681

1346

waited_time.tv_nsec = (now.tv_nsec

1682

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

1347

- mc.current_server->last_seen.tv_nsec);

1683

1348

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

1684

1349

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

1685

1350

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

1687

1352

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

1688

1353

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

1689

1354

1690

if(debug){

1355

if (debug){

1691

1356

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

1692

1357

block_time);

1693

1358

}

1694

1359

1695

1360

if(block_time <= 0){

1696

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

1697

mc->current_server->port,

1698

mc->current_server->if_index,

1699

mc->current_server->af, mc);

1361

ret = start_mandos_communication(mc.current_server->ip,

1362

mc.current_server->port,

1363

mc.current_server->if_index,

1364

mc.current_server->af);

1700

1365

if(ret == 0){

1701

avahi_simple_poll_quit(s);

1366

avahi_simple_poll_quit(mc.simple_poll);

1702

1367

return 0;

1703

1368

}

1704

1369

ret = clock_gettime(CLOCK_MONOTONIC,

1705

&mc->current_server->last_seen);

1370

&mc.current_server->last_seen);

1706

1371

if(ret == -1){

1707

1372

perror_plus("clock_gettime");

1708

1373

return -1;

1709

1374

}

1710

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

1375

mc.current_server = mc.current_server->next;

1711

1376

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

1712

1377

servers, but don't block */

1713

1378

}

1715

1380

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

1716

1381

}

1717

1382

if(ret != 0){

1718

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

1383

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

1719

1384

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

1720

1385

}

1721

1386

}

1722

1387

}

1723

1388

}

1724

1389

1725

__attribute__((nonnull))

1726

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

1390

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

1727

1391

const float delay){

1728

struct dirent **direntries = NULL;

1729

if(hookdir_fd == -1){

1730

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

1731

| O_CLOEXEC);

1732

if(hookdir_fd == -1){

1733

if(errno == ENOENT){

1734

if(debug){

1735

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

1736

" found\n", hookdir);

1737

}

1738

} else {

1739

perror_plus("open");

1740

}

1741

return;

1742

}

1743

}

1744

#ifdef __GLIBC__

1745

#if __GLIBC_PREREQ(2, 15)

1746

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

1747

runnable_hook, alphasort);

1748

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

1749

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

1750

alphasort);

1751

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

1752

#else /* not __GLIBC__ */

1753

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

1754

alphasort);

1755

#endif /* not __GLIBC__ */

1392

struct dirent **direntries;

1393

struct dirent *direntry;

1394

int ret;

1395

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

1396

alphasort);

1756

1397

if(numhooks == -1){

1757

1398

perror_plus("scandir");

1758

return;

1759

}

1760

struct dirent *direntry;

1761

int ret;

1762

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

1763

if(devnull == -1){

1764

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

1765

return;

1766

}

1767

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

1768

direntry = direntries[i];

1769

if(debug){

1770

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

1771

direntry->d_name);

1772

}

1773

pid_t hook_pid = fork();

1774

if(hook_pid == 0){

1775

/* Child */

1776

/* Raise privileges */

1777

errno = raise_privileges_permanently();

1778

if(errno != 0){

1779

perror_plus("Failed to raise privileges");

1780

_exit(EX_NOPERM);

1781

}

1782

/* Set group */

1783

errno = 0;

1784

ret = setgid(0);

1785

if(ret == -1){

1786

perror_plus("setgid");

1787

_exit(EX_NOPERM);

1788

}

1789

/* Reset supplementary groups */

1790

errno = 0;

1791

ret = setgroups(0, NULL);

1792

if(ret == -1){

1793

perror_plus("setgroups");

1794

_exit(EX_NOPERM);

1795

}

1796

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

1797

if(ret == -1){

1798

perror_plus("setenv");

1799

_exit(EX_OSERR);

1800

}

1801

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

1802

if(ret == -1){

1803

perror_plus("setenv");

1804

_exit(EX_OSERR);

1805

}

1806

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

1807

if(ret == -1){

1808

perror_plus("setenv");

1809

_exit(EX_OSERR);

1810

}

1811

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

1812

if(ret == -1){

1813

perror_plus("setenv");

1814

_exit(EX_OSERR);

1815

}

1816

char *delaystring;

1817

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

1818

if(ret == -1){

1399

} else {

1400

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

1401

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

1402

direntry = direntries[i];

1403

char *fullname = NULL;

1404

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

1405

if(ret < 0){

1819

1406

perror_plus("asprintf");

1820

_exit(EX_OSERR);

1821

}

1822

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

1823

if(ret == -1){

1407

continue;

1408

}

1409

if(debug){

1410

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

1411

direntry->d_name);

1412

}

1413

pid_t hook_pid = fork();

1414

if(hook_pid == 0){

1415

/* Child */

1416

/* Raise privileges */

1417

errno = 0;

1418

ret = seteuid(0);

1419

if(ret == -1){

1420

perror_plus("seteuid");

1421

}

1422

/* Raise privileges even more */

1423

errno = 0;

1424

ret = setuid(0);

1425

if(ret == -1){

1426

perror_plus("setuid");

1427

}

1428

/* Set group */

1429

errno = 0;

1430

ret = setgid(0);

1431

if(ret == -1){

1432

perror_plus("setgid");

1433

}

1434

/* Reset supplementary groups */

1435

errno = 0;

1436

ret = setgroups(0, NULL);

1437

if(ret == -1){

1438

perror_plus("setgroups");

1439

}

1440

dup2(devnull, STDIN_FILENO);

1441

close(devnull);

1442

dup2(STDERR_FILENO, STDOUT_FILENO);

1443

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

1444

if(ret == -1){

1445

perror_plus("setenv");

1446

_exit(EX_OSERR);

1447

}

1448

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

1449

if(ret == -1){

1450

perror_plus("setenv");

1451

_exit(EX_OSERR);

1452

}

1453

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

1454

if(ret == -1){

1455

perror_plus("setenv");

1456

_exit(EX_OSERR);

1457

}

1458

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

1459

if(ret == -1){

1460

perror_plus("setenv");

1461

_exit(EX_OSERR);

1462

}

1463

char *delaystring;

1464

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

1465

if(ret == -1){

1466

perror_plus("asprintf");

1467

_exit(EX_OSERR);

1468

}

1469

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

1470

if(ret == -1){

1471

free(delaystring);

1472

perror_plus("setenv");

1473

_exit(EX_OSERR);

1474

}

1824

1475

free(delaystring);

1825

perror_plus("setenv");

1826

_exit(EX_OSERR);

1827

}

1828

free(delaystring);

1829

if(connect_to != NULL){

1830

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

1831

if(ret == -1){

1832

perror_plus("setenv");

1833

_exit(EX_OSERR);

1834

}

1835

}

1836

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

1837

direntry->d_name,

1838

O_RDONLY));

1839

if(hook_fd == -1){

1840

perror_plus("openat");

1841

_exit(EXIT_FAILURE);

1842

}

1843

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

1844

perror_plus("close");

1845

_exit(EXIT_FAILURE);

1846

}

1847

ret = dup2(devnull, STDIN_FILENO);

1848

if(ret == -1){

1849

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

1850

_exit(EX_OSERR);

1851

}

1852

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

1853

if(ret == -1){

1854

perror_plus("close");

1855

_exit(EX_OSERR);

1856

}

1857

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1858

if(ret == -1){

1859

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

1860

_exit(EX_OSERR);

1861

}

1862

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

1863

environ) == -1){

1864

perror_plus("fexecve");

1865

_exit(EXIT_FAILURE);

1866

}

1867

} else {

1868

if(hook_pid == -1){

1869

perror_plus("fork");

1870

free(direntry);

1871

continue;

1872

}

1873

int status;

1874

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

1875

perror_plus("waitpid");

1876

free(direntry);

1877

continue;

1878

}

1879

if(WIFEXITED(status)){

1880

if(WEXITSTATUS(status) != 0){

1881

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

1882

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

1883

WEXITSTATUS(status));

1884

free(direntry);

1885

continue;

1886

}

1887

} else if(WIFSIGNALED(status)){

1888

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

1889

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

1890

WTERMSIG(status));

1891

free(direntry);

1892

continue;

1893

} else {

1894

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

1895

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

1896

free(direntry);

1897

continue;

1898

}

1899

}

1900

if(debug){

1901

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

1902

direntry->d_name);

1903

}

1904

free(direntry);

1905

}

1906

free(direntries);

1907

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

1908

perror_plus("close");

1909

} else {

1910

hookdir_fd = -1;

1911

}

1912

close(devnull);

1913

}

1914

1915

__attribute__((nonnull, warn_unused_result))

1916

error_t bring_up_interface(const char *const interface,

1917

const float delay){

1918

error_t old_errno = errno;

1919

int ret;

1920

struct ifreq network;

1921

unsigned int if_index = if_nametoindex(interface);

1922

if(if_index == 0){

1923

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

1924

errno = old_errno;

1925

return ENXIO;

1926

}

1927

1928

if(quit_now){

1929

errno = old_errno;

1930

return EINTR;

1931

}

1932

1933

if(not interface_is_up(interface)){

1934

error_t ret_errno = 0, ioctl_errno = 0;

1935

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

1936

ret_errno = errno;

1937

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

1938

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

1939

errno = old_errno;

1940

return ret_errno;

1941

}

1942

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

1943

1944

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

1945

if(sd == -1){

1946

ret_errno = errno;

1947

perror_plus("socket");

1948

errno = old_errno;

1949

return ret_errno;

1950

}

1951

1952

if(quit_now){

1953

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

1954

if(ret == -1){

1955

perror_plus("close");

1956

}

1957

errno = old_errno;

1958

return EINTR;

1959

}

1960

1961

if(debug){

1962

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

1963

interface);

1964

}

1965

1966

/* Raise privileges */

1967

ret_errno = raise_privileges();

1968

if(ret_errno != 0){

1969

errno = ret_errno;

1970

perror_plus("Failed to raise privileges");

1971

}

1972

1973

#ifdef __linux__

1974

int ret_linux;

1975

bool restore_loglevel = false;

1976

if(ret_errno == 0){

1977

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1978

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

1979

ret_linux = klogctl(8, NULL, 5);

1980

if(ret_linux == -1){

1981

perror_plus("klogctl");

1982

} else {

1983

restore_loglevel = true;

1984

}

1985

}

1986

#endif /* __linux__ */

1987

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

1988

ioctl_errno = errno;

1989

#ifdef __linux__

1990

if(restore_loglevel){

1991

ret_linux = klogctl(7, NULL, 0);

1992

if(ret_linux == -1){

1993

perror_plus("klogctl");

1994

}

1995

}

1996

#endif /* __linux__ */

1997

1998

/* If raise_privileges() succeeded above */

1999

if(ret_errno == 0){

2000

/* Lower privileges */

2001

ret_errno = lower_privileges();

2002

if(ret_errno != 0){

2003

errno = ret_errno;

2004

perror_plus("Failed to lower privileges");

2005

}

2006

}

2007

2008

/* Close the socket */

2009

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

2010

if(ret == -1){

2011

perror_plus("close");

2012

}

2013

2014

if(ret_setflags == -1){

2015

errno = ioctl_errno;

2016

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

2017

errno = old_errno;

2018

return ioctl_errno;

2019

}

2020

} else if(debug){

2021

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

2022

interface);

2023

}

2024

2025

/* Sleep checking until interface is running.

2026

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

2027

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

2028

if(interface_is_running(interface)){

2029

break;

2030

}

2031

struct timespec sleeptime = { .tv_nsec = 250000000 };

2032

ret = nanosleep(&sleeptime, NULL);

2033

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

2034

perror_plus("nanosleep");

2035

}

2036

}

2037

2038

errno = old_errno;

2039

return 0;

2040

}

2041

2042

__attribute__((nonnull, warn_unused_result))

2043

error_t take_down_interface(const char *const interface){

2044

error_t old_errno = errno;

2045

struct ifreq network;

2046

unsigned int if_index = if_nametoindex(interface);

2047

if(if_index == 0){

2048

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

2049

errno = old_errno;

2050

return ENXIO;

2051

}

2052

if(interface_is_up(interface)){

2053

error_t ret_errno = 0, ioctl_errno = 0;

2054

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

2055

ret_errno = errno;

2056

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

2057

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

2058

errno = old_errno;

2059

return ret_errno;

2060

}

2061

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

2062

2063

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

2064

if(sd == -1){

2065

ret_errno = errno;

2066

perror_plus("socket");

2067

errno = old_errno;

2068

return ret_errno;

2069

}

2070

2071

if(debug){

2072

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

2073

interface);

2074

}

2075

2076

/* Raise privileges */

2077

ret_errno = raise_privileges();

2078

if(ret_errno != 0){

2079

errno = ret_errno;

2080

perror_plus("Failed to raise privileges");

2081

}

2082

2083

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

2084

ioctl_errno = errno;

2085

2086

/* If raise_privileges() succeeded above */

2087

if(ret_errno == 0){

2088

/* Lower privileges */

2089

ret_errno = lower_privileges();

2090

if(ret_errno != 0){

2091

errno = ret_errno;

2092

perror_plus("Failed to lower privileges");

2093

}

2094

}

2095

2096

/* Close the socket */

2097

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

2098

if(ret == -1){

2099

perror_plus("close");

2100

}

2101

2102

if(ret_setflags == -1){

2103

errno = ioctl_errno;

2104

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2105

errno = old_errno;

2106

return ioctl_errno;

2107

}

2108

} else if(debug){

2109

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

2110

interface);

2111

}

2112

2113

errno = old_errno;

2114

return 0;

1476

if(connect_to != NULL){

1477

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

1478

if(ret == -1){

1479

perror_plus("setenv");

1480

_exit(EX_OSERR);

1481

}

1482

}

1483

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

1484

perror_plus("execl");

1485

_exit(EXIT_FAILURE);

1486

}

1487

} else {

1488

int status;

1489

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

1490

perror_plus("waitpid");

1491

free(fullname);

1492

continue;

1493

}

1494

if(WIFEXITED(status)){

1495

if(WEXITSTATUS(status) != 0){

1496

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

1497

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

1498

WEXITSTATUS(status));

1499

free(fullname);

1500

continue;

1501

}

1502

} else if(WIFSIGNALED(status)){

1503

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

1504

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

1505

WTERMSIG(status));

1506

free(fullname);

1507

continue;

1508

} else {

1509

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

1510

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

1511

free(fullname);

1512

continue;

1513

}

1514

}

1515

free(fullname);

1516

if(debug){

1517

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

1518

direntry->d_name);

1519

}

1520

}

1521

close(devnull);

1522

}

1523

return true;

2115

1524

}

2116

1525

2117

1526

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

2118

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

2119

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

2120

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

2121

.interfaces = NULL, .interfaces_size = 0 };

2122

1527

AvahiSServiceBrowser *sb = NULL;

2123

error_t ret_errno;

1528

int error;

2124

1529

int ret;

2125

1530

intmax_t tmpmax;

2126

1531

char *tmp;

2127

1532

int exitcode = EXIT_SUCCESS;

2128

char *interfaces_to_take_down = NULL;

2129

size_t interfaces_to_take_down_size = 0;

2130

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

2131

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

2132

char *tempdir = NULL;

1533

const char *interface = "";

1534

struct ifreq network;

1535

int sd = -1;

1536

bool take_down_interface = false;

1537

uid_t uid;

1538

gid_t gid;

1539

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

1540

bool tempdir_created = false;

2133

1541

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

2134

1542

const char *seckey = PATHDIR "/" SECKEY;

2135

1543

const char *pubkey = PATHDIR "/" PUBKEY;

2136

char *interfaces_hooks = NULL;

2137

1544

2138

1545

bool gnutls_initialized = false;

2139

1546

bool gpgme_initialized = false;

2230

1637

connect_to = arg;

2231

1638

break;

2232

1639

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

2233

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

2234

arg, (int)',');

2235

if(ret_errno != 0){

2236

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

2237

}

1640

interface = arg;

2238

1641

break;

2239

1642

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

2240

1643

seckey = arg;

2312

1715

goto end;

2313

1716

}

2314

1717

}

2315

1718

2316

1719

{

2317

1720

/* Work around Debian bug #633582:

2318

1721

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

2319

1722

2320

/* Re-raise privileges */

2321

ret_errno = raise_privileges();

2322

if(ret_errno != 0){

2323

errno = ret_errno;

2324

perror_plus("Failed to raise privileges");

1723

/* Re-raise priviliges */

1724

errno = 0;

1725

ret = seteuid(0);

1726

if(ret == -1){

1727

perror_plus("seteuid");

2325

1728

} else {

2326

1729

struct stat st;

2327

1730

2345

1748

TEMP_FAILURE_RETRY(close(seckey_fd));

2346

1749

}

2347

1750

}

2348

1751

2349

1752

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

2350

1753

int pubkey_fd = open(pubkey, O_RDONLY);

2351

1754

if(pubkey_fd == -1){

2366

1769

TEMP_FAILURE_RETRY(close(pubkey_fd));

2367

1770

}

2368

1771

}

2369

1772

2370

1773

/* Lower privileges */

2371

ret_errno = lower_privileges();

2372

if(ret_errno != 0){

2373

errno = ret_errno;

2374

perror_plus("Failed to lower privileges");

2375

}

2376

}

2377

}

2378

2379

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

2380

{

2381

char *interface = NULL;

2382

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

2383

interface))){

2384

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

2385

and if_nametoindex(interface) == 0){

2386

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

2387

fprintf_plus(stderr, "Not using nonexisting interface"

2388

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

2389

}

2390

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

2391

interface = NULL;

1774

errno = 0;

1775

ret = seteuid(uid);

1776

if(ret == -1){

1777

perror_plus("seteuid");

2392

1778

}

2393

1779

}

2394

1780

}

2395

1781

2396

1782

/* Run network hooks */

2397

{

2398

if(mc.interfaces != NULL){

2399

interfaces_hooks = malloc(mc.interfaces_size);

2400

if(interfaces_hooks == NULL){

2401

perror_plus("malloc");

2402

goto end;

2403

}

2404

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

2405

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

2406

}

2407

run_network_hooks("start", interfaces_hooks != NULL ?

2408

interfaces_hooks : "", delay);

1783

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

1784

goto end;

2409

1785

}

2410

1786

2411

1787

if(not debug){

2412

1788

avahi_set_log_function(empty_log);

2413

1789

}

2414

1790

1791

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

1792

struct dirent **direntries;

1793

/* First look for interfaces that are up */

1794

ret = scandir(sys_class_net, &direntries, up_interface,

1795

alphasort);

1796

if(ret == 0){

1797

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

1798

free(direntries);

1799

ret = scandir(sys_class_net, &direntries, good_interface,

1800

alphasort);

1801

}

1802

if(ret >= 1){

1803

/* Pick the first interface returned */

1804

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

1805

if(debug){

1806

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

1807

}

1808

if(interface == NULL){

1809

perror_plus("malloc");

1810

free(direntries);

1811

exitcode = EXIT_FAILURE;

1812

goto end;

1813

}

1814

free(direntries);

1815

} else {

1816

free(direntries);

1817

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

1818

exitcode = EXIT_FAILURE;

1819

goto end;

1820

}

1821

}

1822

2415

1823

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

2416

1824

from the signal handler */

2417

1825

/* Initialize the pseudo-RNG for Avahi */

2418

1826

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

2419

simple_poll = avahi_simple_poll_new();

2420

if(simple_poll == NULL){

1827

mc.simple_poll = avahi_simple_poll_new();

1828

if(mc.simple_poll == NULL){

2421

1829

fprintf_plus(stderr,

2422

1830

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

2423

1831

exitcode = EX_UNAVAILABLE;

2487

1895

}

2488

1896

}

2489

1897

2490

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

2491

if(mc.interfaces == NULL){

2492

struct dirent **direntries = NULL;

2493

/* Look for any good interfaces */

2494

ret = scandir(sys_class_net, &direntries, good_interface,

2495

alphasort);

2496

if(ret >= 1){

2497

/* Add all found interfaces to interfaces list */

2498

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

2499

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

2500

direntries[i]->d_name);

2501

if(ret_errno != 0){

2502

errno = ret_errno;

2503

perror_plus("argz_add");

2504

free(direntries[i]);

2505

continue;

2506

}

2507

if(debug){

2508

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

2509

direntries[i]->d_name);

2510

}

2511

free(direntries[i]);

2512

}

2513

free(direntries);

2514

} else {

2515

if(ret == 0){

2516

free(direntries);

2517

}

2518

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

2519

exitcode = EXIT_FAILURE;

2520

goto end;

2521

}

2522

}

2523

2524

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

2525

{

2526

char *interface = NULL;

2527

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

2528

interface))){

2529

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

2530

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

2531

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

2532

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

2533

interface);

2534

interface = NULL;

2535

while((interface = argz_next(mc.interfaces,

2536

mc.interfaces_size, interface))){

2537

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

2538

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

2539

interface);

2540

interface = NULL;

1898

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

1899

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

1900

if_index = (AvahiIfIndex) if_nametoindex(interface);

1901

if(if_index == 0){

1902

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

1903

exitcode = EX_UNAVAILABLE;

1904

goto end;

1905

}

1906

1907

if(quit_now){

1908

goto end;

1909

}

1910

1911

/* Re-raise priviliges */

1912

errno = 0;

1913

ret = seteuid(0);

1914

if(ret == -1){

1915

perror_plus("seteuid");

1916

}

1917

1918

#ifdef __linux__

1919

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1920

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

1921

ret = klogctl(8, NULL, 5);

1922

bool restore_loglevel = true;

1923

if(ret == -1){

1924

restore_loglevel = false;

1925

perror_plus("klogctl");

1926

}

1927

#endif /* __linux__ */

1928

1929

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1930

if(sd < 0){

1931

perror_plus("socket");

1932

exitcode = EX_OSERR;

1933

#ifdef __linux__

1934

if(restore_loglevel){

1935

ret = klogctl(7, NULL, 0);

1936

if(ret == -1){

1937

perror_plus("klogctl");

1938

}

1939

}

1940

#endif /* __linux__ */

1941

/* Lower privileges */

1942

errno = 0;

1943

ret = seteuid(uid);

1944

if(ret == -1){

1945

perror_plus("seteuid");

1946

}

1947

goto end;

1948

}

1949

strcpy(network.ifr_name, interface);

1950

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

1951

if(ret == -1){

1952

perror_plus("ioctl SIOCGIFFLAGS");

1953

#ifdef __linux__

1954

if(restore_loglevel){

1955

ret = klogctl(7, NULL, 0);

1956

if(ret == -1){

1957

perror_plus("klogctl");

1958

}

1959

}

1960

#endif /* __linux__ */

1961

exitcode = EX_OSERR;

1962

/* Lower privileges */

1963

errno = 0;

1964

ret = seteuid(uid);

1965

if(ret == -1){

1966

perror_plus("seteuid");

1967

}

1968

goto end;

1969

}

1970

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

1971

network.ifr_flags |= IFF_UP;

1972

take_down_interface = true;

1973

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

1974

if(ret == -1){

1975

take_down_interface = false;

1976

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1977

exitcode = EX_OSERR;

1978

#ifdef __linux__

1979

if(restore_loglevel){

1980

ret = klogctl(7, NULL, 0);

1981

if(ret == -1){

1982

perror_plus("klogctl");

2541

1983

}

2542

1984

}

1985

#endif /* __linux__ */

1986

/* Lower privileges */

1987

errno = 0;

1988

ret = seteuid(uid);

1989

if(ret == -1){

1990

perror_plus("seteuid");

1991

}

1992

goto end;

1993

}

1994

}

1995

/* Sleep checking until interface is running.

1996

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

1997

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

1998

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

1999

if(ret == -1){

2000

perror_plus("ioctl SIOCGIFFLAGS");

2001

} else if(network.ifr_flags & IFF_RUNNING){

2543

2002

break;

2544

2003

}

2545

bool interface_was_up = interface_is_up(interface);

2546

errno = bring_up_interface(interface, delay);

2547

if(not interface_was_up){

2548

if(errno != 0){

2549

perror_plus("Failed to bring up interface");

2550

} else {

2551

errno = argz_add(&interfaces_to_take_down,

2552

&interfaces_to_take_down_size,

2553

interface);

2554

if(errno != 0){

2555

perror_plus("argz_add");

2556

}

2557

}

2558

}

2559

}

2560

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

2561

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

2562

}

2563

}

2564

2565

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

2566

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

2567

if(debug){

2568

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

2569

mc.interfaces);

2570

}

2571

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

2004

struct timespec sleeptime = { .tv_nsec = 250000000 };

2005

ret = nanosleep(&sleeptime, NULL);

2006

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

2007

perror_plus("nanosleep");

2008

}

2009

}

2010

if(not take_down_interface){

2011

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

2012

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

2013

if(ret == -1){

2014

perror_plus("close");

2015

}

2016

}

2017

#ifdef __linux__

2018

if(restore_loglevel){

2019

/* Restores kernel loglevel to default */

2020

ret = klogctl(7, NULL, 0);

2021

if(ret == -1){

2022

perror_plus("klogctl");

2023

}

2024

}

2025

#endif /* __linux__ */

2026

/* Lower privileges */

2027

errno = 0;

2028

/* Lower privileges */

2029

ret = seteuid(uid);

2030

if(ret == -1){

2031

perror_plus("seteuid");

2032

}

2572

2033

}

2573

2034

2574

2035

if(quit_now){

2575

2036

goto end;

2576

2037

}

2577

2038

2578

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

2039

ret = init_gnutls_global(pubkey, seckey);

2579

2040

if(ret == -1){

2580

2041

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

2581

2042

exitcode = EX_UNAVAILABLE;

2588

2049

goto end;

2589

2050

}

2590

2051

2591

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

2592

tempdir = mkdtemp(run_tempdir);

2593

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

2594

if(debug){

2595

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

2596

run_tempdir, old_tempdir);

2597

}

2598

tempdir = mkdtemp(old_tempdir);

2599

}

2600

if(tempdir == NULL){

2052

if(mkdtemp(tempdir) == NULL){

2601

2053

perror_plus("mkdtemp");

2602

2054

goto end;

2603

2055

}

2056

tempdir_created = true;

2604

2057

2605

2058

if(quit_now){

2606

2059

goto end;

2607

2060

}

2608

2061

2609

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

2062

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

2610

2063

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

2611

2064

exitcode = EX_UNAVAILABLE;

2612

2065

goto end;

2622

2075

/* Connect directly, do not use Zeroconf */

2623

2076

/* (Mainly meant for debugging) */

2624

2077

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

2625

2626

2078

if(address == NULL){

2627

2079

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

2628

2080

exitcode = EX_USAGE;

2633

2085

goto end;

2634

2086

}

2635

2087

2636

in_port_t port;

2088

uint16_t port;

2637

2089

errno = 0;

2638

2090

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

2639

2091

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

2640

or tmpmax != (in_port_t)tmpmax){

2092

or tmpmax != (uint16_t)tmpmax){

2641

2093

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

2642

2094

exitcode = EX_USAGE;

2643

2095

goto end;

2644

2096

}

2645

2097

2646

2098

if(quit_now){

2647

2099

goto end;

2648

2100

}

2649

2101

2650

port = (in_port_t)tmpmax;

2102

port = (uint16_t)tmpmax;

2651

2103

*address = '\0';

2652

2104

/* Colon in address indicates IPv6 */

2653

2105

int af;

2669

2121

}

2670

2122

2671

2123

while(not quit_now){

2672

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

2673

&mc);

2124

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

2674

2125

if(quit_now or ret == 0){

2675

2126

break;

2676

2127

}

2678

2129

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

2679

2130

(int)retry_interval);

2680

2131

}

2681

sleep((unsigned int)retry_interval);

2132

sleep((int)retry_interval);

2682

2133

}

2683

2134

2684

if(not quit_now){

2135

if (not quit_now){

2685

2136

exitcode = EXIT_SUCCESS;

2686

2137

}

2687

2138

2702

2153

config.publish_domain = 0;

2703

2154

2704

2155

/* Allocate a new server */

2705

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2706

&config, NULL, NULL, &ret_errno);

2156

mc.server = avahi_server_new(avahi_simple_poll_get

2157

(mc.simple_poll), &config, NULL,

2158

NULL, &error);

2707

2159

2708

2160

/* Free the Avahi configuration data */

2709

2161

avahi_server_config_free(&config);

2712

2164

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

2713

2165

if(mc.server == NULL){

2714

2166

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

2715

avahi_strerror(ret_errno));

2167

avahi_strerror(error));

2716

2168

exitcode = EX_UNAVAILABLE;

2717

2169

goto end;

2718

2170

}

2724

2176

/* Create the Avahi service browser */

2725

2177

sb = avahi_s_service_browser_new(mc.server, if_index,

2726

2178

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2727

NULL, 0, browse_callback,

2728

(void *)&mc);

2179

NULL, 0, browse_callback, NULL);

2729

2180

if(sb == NULL){

2730

2181

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

2731

2182

avahi_strerror(avahi_server_errno(mc.server)));

2742

2193

if(debug){

2743

2194

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

2744

2195

}

2745

2746

ret = avahi_loop_with_timeout(simple_poll,

2747

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

2196

2197

ret = avahi_loop_with_timeout(mc.simple_poll,

2198

(int)(retry_interval * 1000));

2748

2199

if(debug){

2749

2200

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

2750

2201

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

2757

2208

}

2758

2209

2759

2210

/* Cleanup things */

2760

free(mc.interfaces);

2761

2762

2211

if(sb != NULL)

2763

2212

avahi_s_service_browser_free(sb);

2764

2213

2765

2214

if(mc.server != NULL)

2766

2215

avahi_server_free(mc.server);

2767

2216

2768

if(simple_poll != NULL)

2769

avahi_simple_poll_free(simple_poll);

2217

if(mc.simple_poll != NULL)

2218

avahi_simple_poll_free(mc.simple_poll);

2770

2219

2771

2220

if(gnutls_initialized){

2772

2221

gnutls_certificate_free_credentials(mc.cred);

2784

2233

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

2785

2234

while(mc.current_server != NULL){

2786

2235

server *next = mc.current_server->next;

2787

#ifdef __GNUC__

2788

#pragma GCC diagnostic push

2789

#pragma GCC diagnostic ignored "-Wcast-qual"

2790

#endif

2791

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

2792

#ifdef __GNUC__

2793

#pragma GCC diagnostic pop

2794

#endif

2795

2236

free(mc.current_server);

2796

2237

mc.current_server = next;

2797

2238

}

2798

2239

}

2799

2240

2800

/* Re-raise privileges */

2241

/* Run network hooks */

2242

run_network_hooks("stop", interface, delay);

2243

2244

/* Re-raise priviliges */

2801

2245

{

2802

ret_errno = raise_privileges();

2803

if(ret_errno != 0){

2804

errno = ret_errno;

2805

perror_plus("Failed to raise privileges");

2806

} else {

2807

2808

/* Run network hooks */

2809

run_network_hooks("stop", interfaces_hooks != NULL ?

2810

interfaces_hooks : "", delay);

2811

2812

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

2813

{

2814

char *interface = NULL;

2815

while((interface=argz_next(interfaces_to_take_down,

2816

interfaces_to_take_down_size,

2817

interface))){

2818

ret_errno = take_down_interface(interface);

2819

if(ret_errno != 0){

2820

errno = ret_errno;

2821

perror_plus("Failed to take down interface");

2822

}

2823

}

2824

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

2825

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

2826

" down\n");

2827

}

2828

}

2246

errno = 0;

2247

ret = seteuid(0);

2248

if(ret == -1){

2249

perror_plus("seteuid");

2829

2250

}

2830

2251

2831

ret_errno = lower_privileges_permanently();

2832

if(ret_errno != 0){

2833

errno = ret_errno;

2834

perror_plus("Failed to lower privileges permanently");

2252

/* Take down the network interface */

2253

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

2254

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

2255

if(ret == -1){

2256

perror_plus("ioctl SIOCGIFFLAGS");

2257

} else if(network.ifr_flags & IFF_UP){

2258

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

2259

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

2260

if(ret == -1){

2261

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2262

}

2263

}

2264

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

2265

if(ret == -1){

2266

perror_plus("close");

2267

}

2835

2268

}

2836

2269

}

2837

2838

free(interfaces_to_take_down);

2839

free(interfaces_hooks);

2270

/* Lower privileges permanently */

2271

errno = 0;

2272

ret = setuid(uid);

2273

if(ret == -1){

2274

perror_plus("setuid");

2275

}

2840

2276

2841

2277

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

2842

if(tempdir != NULL){

2278

if(tempdir_created){

2843

2279

struct dirent **direntries = NULL;

2844

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

2845

| O_NOFOLLOW

2846

| O_DIRECTORY

2847

| O_PATH));

2848

if(tempdir_fd == -1){

2849

perror_plus("open");

2850

} else {

2851

#ifdef __GLIBC__

2852

#if __GLIBC_PREREQ(2, 15)

2853

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

2854

notdotentries, alphasort);

2855

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

2856

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

2857

alphasort);

2858

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

2859

#else /* not __GLIBC__ */

2860

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

2861

alphasort);

2862

#endif /* not __GLIBC__ */

2863

if(numentries >= 0){

2864

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

2865

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

2866

if(ret == -1){

2867

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

2868

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

2869

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

2870

}

2871

free(direntries[i]);

2872

}

2873

2874

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

2875

free(direntries);

2876

if(numentries == -1){

2877

perror_plus("scandir");

2878

}

2879

ret = rmdir(tempdir);

2880

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

2881

perror_plus("rmdir");

2882

}

2280

struct dirent *direntry = NULL;

2281

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

2282

alphasort);

2283

if (numentries > 0){

2284

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

2285

direntry = direntries[i];

2286

char *fullname = NULL;

2287

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

2288

direntry->d_name);

2289

if(ret < 0){

2290

perror_plus("asprintf");

2291

continue;

2292

}

2293

ret = remove(fullname);

2294

if(ret == -1){

2295

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

2296

strerror(errno));

2297

}

2298

free(fullname);

2883

2299

}

2884

TEMP_FAILURE_RETRY(close(tempdir_fd));

2300

}

2301

2302

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

2303

free(direntries);

2304

if (numentries == -1){

2305

perror_plus("scandir");

2306

}

2307

ret = rmdir(tempdir);

2308

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

2309

perror_plus("rmdir");

2885

2310

}

2886

2311

}

2887

2312