/mandos/release : revision 237.2.74

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

26

* along with this program. If not, see

27

* <http://www.gnu.org/licenses/>.

28

*

29

* Contact the authors at <mandos@recompile.se>.

29

* Contact the authors at <mandos@fukt.bsnet.se>.

30

*/

31

32

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

33

#ifndef _LARGEFILE_SOURCE

34

33

#define _LARGEFILE_SOURCE

35

#endif

36

#ifndef _FILE_OFFSET_BITS

37

34

#define _FILE_OFFSET_BITS 64

38

#endif

39

35

40

36

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

41

37

43

39

stdout, ferror(), remove() */

44

40

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

45

41

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

46

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

47

strtof(), abort() */

42

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

43

srand(), strtof() */

48

44

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

49

45

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

50

46

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

53

49

sockaddr_in6, PF_INET6,

54

50

SOCK_STREAM, uid_t, gid_t, open(),

55

51

opendir(), DIR */

56

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

52

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

57

53

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

58

54

inet_pton(), connect() */

59

55

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

62

58

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

63

59

strtoimax() */

64

60

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

65

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

66

program_invocation_short_name */

67

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

61

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

62

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

68

63

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

69

64

SIOCSIFFLAGS, if_indextoname(),

70

65

if_nametoindex(), IF_NAMESIZE */

72

67

INET_ADDRSTRLEN, INET6_ADDRSTRLEN

73

68

*/

74

69

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

75

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

76

setgid(), pause() */

77

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

70

getuid(), getgid(), setuid(),

71

setgid() */

72

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

78

73

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

79

74

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

80

75

argp_state, struct argp,

81

76

argp_parse(), ARGP_KEY_ARG,

82

77

ARGP_KEY_END, ARGP_ERR_UNKNOWN */

83

78

#include <signal.h> /* sigemptyset(), sigaddset(),

84

sigaction(), SIGTERM, sig_atomic_t,

85

raise() */

86

#include <sysexits.h> /* EX_OSERR, EX_USAGE, EX_UNAVAILABLE,

87

EX_NOHOST, EX_IOERR, EX_PROTOCOL */

79

sigaction(), SIGTERM, sigaction,

80

sig_atomic_t */

88

81

89

82

#ifdef __linux__

90

83

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

123

116

#define PATHDIR "/conf/conf.d/mandos"

124

117

#define SECKEY "seckey.txt"

125

118

#define PUBKEY "pubkey.txt"

126

#define HOOKDIR "/lib/mandos/network-hooks.d"

127

119

128

120

bool debug = false;

129

121

static const char mandos_protocol_version[] = "1";

130

122

const char *argp_program_version = "mandos-client " VERSION;

131

const char *argp_program_bug_address = "<mandos@recompile.se>";

132

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

133

char *connect_to = NULL;

134

135

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

136

typedef struct server{

137

const char *ip;

138

uint16_t port;

139

AvahiIfIndex if_index;

140

int af;

141

struct timespec last_seen;

142

struct server *next;

143

struct server *prev;

144

} server;

123

const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";

145

124

146

125

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

147

126

typedef struct {

152

131

gnutls_dh_params_t dh_params;

153

132

const char *priority;

154

133

gpgme_ctx_t ctx;

155

server *current_server;

156

134

} mandos_context;

157

135

158

136

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

159

137

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

160

138

.dh_bits = 1024, .priority = "SECURE256"

161

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

162

.current_server = NULL };

163

164

sig_atomic_t quit_now = 0;

165

int signal_received = 0;

166

167

/* Function to use when printing errors */

168

void perror_plus(const char *print_text){

169

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

170

program_invocation_short_name);

171

perror(print_text);

172

}

139

":!CTYPE-X.509:+CTYPE-OPENPGP" };

173

140

174

141

/*

175

142

* Make additional room in "buffer" for at least BUFFER_SIZE more

188

155

return buffer_capacity;

189

156

}

190

157

191

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

192

int add_server(const char *ip, uint16_t port,

193

AvahiIfIndex if_index,

194

int af){

195

int ret;

196

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

197

if(new_server == NULL){

198

perror_plus("malloc");

199

return -1;

200

}

201

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

202

.port = port,

203

.if_index = if_index,

204

.af = af };

205

if(new_server->ip == NULL){

206

perror_plus("strdup");

207

return -1;

208

}

209

/* Special case of first server */

210

if (mc.current_server == NULL){

211

new_server->next = new_server;

212

new_server->prev = new_server;

213

mc.current_server = new_server;

214

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

215

} else {

216

new_server->next = mc.current_server;

217

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

218

new_server->prev->next = new_server;

219

mc.current_server->prev = new_server;

220

}

221

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

222

if(ret == -1){

223

perror_plus("clock_gettime");

224

return -1;

225

}

226

return 0;

227

}

228

229

158

/*

230

159

* Initialize GPGME.

231

160

*/

232

161

static bool init_gpgme(const char *seckey,

233

162

const char *pubkey, const char *tempdir){

163

int ret;

234

164

gpgme_error_t rc;

235

165

gpgme_engine_info_t engine_info;

236

166

239

169

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

240

170

*/

241

171

bool import_key(const char *filename){

242

int ret;

243

172

int fd;

244

173

gpgme_data_t pgp_data;

245

174

246

175

fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));

247

176

if(fd == -1){

248

perror_plus("open");

177

perror("open");

249

178

return false;

250

179

}

251

180

265

194

266

195

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

267

196

if(ret == -1){

268

perror_plus("close");

197

perror("close");

269

198

}

270

199

gpgme_data_release(pgp_data);

271

200

return true;

284

213

return false;

285

214

}

286

215

287

/* Set GPGME home directory for the OpenPGP engine only */

216

/* Set GPGME home directory for the OpenPGP engine only */

288

217

rc = gpgme_get_engine_info(&engine_info);

289

218

if(rc != GPG_ERR_NO_ERROR){

290

219

fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",

316

245

return false;

317

246

}

318

247

319

return true;

248

return true;

320

249

}

321

250

322

251

/*

376

305

}

377

306

gpgme_recipient_t recipient;

378

307

recipient = result->recipients;

379

while(recipient != NULL){

380

fprintf(stderr, "Public key algorithm: %s\n",

381

gpgme_pubkey_algo_name(recipient->pubkey_algo));

382

fprintf(stderr, "Key ID: %s\n", recipient->keyid);

383

fprintf(stderr, "Secret key available: %s\n",

384

recipient->status == GPG_ERR_NO_SECKEY

385

? "No" : "Yes");

386

recipient = recipient->next;

308

if(recipient){

309

while(recipient != NULL){

310

fprintf(stderr, "Public key algorithm: %s\n",

311

gpgme_pubkey_algo_name(recipient->pubkey_algo));

312

fprintf(stderr, "Key ID: %s\n", recipient->keyid);

313

fprintf(stderr, "Secret key available: %s\n",

314

recipient->status == GPG_ERR_NO_SECKEY

315

? "No" : "Yes");

316

recipient = recipient->next;

317

}

387

318

}

388

319

}

389

320

}

396

327

397

328

/* Seek back to the beginning of the GPGME plaintext data buffer */

398

329

if(gpgme_data_seek(dh_plain, (off_t)0, SEEK_SET) == -1){

399

perror_plus("gpgme_data_seek");

330

perror("gpgme_data_seek");

400

331

plaintext_length = -1;

401

332

goto decrypt_end;

402

333

}

407

338

(size_t)plaintext_length,

408

339

plaintext_capacity);

409

340

if(plaintext_capacity == 0){

410

perror_plus("incbuffer");

341

perror("incbuffer");

411

342

plaintext_length = -1;

412

343

goto decrypt_end;

413

344

}

420

351

break;

421

352

}

422

353

if(ret < 0){

423

perror_plus("gpgme_data_read");

354

perror("gpgme_data_read");

424

355

plaintext_length = -1;

425

356

goto decrypt_end;

426

357

}

483

414

}

484

415

485

416

/* OpenPGP credentials */

486

ret = gnutls_certificate_allocate_credentials(&mc.cred);

417

gnutls_certificate_allocate_credentials(&mc.cred);

487

418

if(ret != GNUTLS_E_SUCCESS){

488

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

419

fprintf(stderr, "GnuTLS memory error: %s\n", /* Spurious warning

420

from

421

-Wunreachable-code

422

*/

489

423

safer_gnutls_strerror(ret));

490

424

gnutls_global_deinit();

491

425

return -1;

538

472

static int init_gnutls_session(gnutls_session_t *session){

539

473

int ret;

540

474

/* GnuTLS session creation */

541

do {

542

ret = gnutls_init(session, GNUTLS_SERVER);

543

if(quit_now){

544

return -1;

545

}

546

} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);

475

ret = gnutls_init(session, GNUTLS_SERVER);

547

476

if(ret != GNUTLS_E_SUCCESS){

548

477

fprintf(stderr, "Error in GnuTLS session initialization: %s\n",

549

478

safer_gnutls_strerror(ret));

551

480

552

481

{

553

482

const char *err;

554

do {

555

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

556

if(quit_now){

557

gnutls_deinit(*session);

558

return -1;

559

}

560

} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);

483

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

561

484

if(ret != GNUTLS_E_SUCCESS){

562

485

fprintf(stderr, "Syntax error at: %s\n", err);

563

486

fprintf(stderr, "GnuTLS error: %s\n",

567

490

}

568

491

}

569

492

570

do {

571

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

572

mc.cred);

573

if(quit_now){

574

gnutls_deinit(*session);

575

return -1;

576

}

577

} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);

493

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

494

mc.cred);

578

495

if(ret != GNUTLS_E_SUCCESS){

579

496

fprintf(stderr, "Error setting GnuTLS credentials: %s\n",

580

497

safer_gnutls_strerror(ret));

583

500

}

584

501

585

502

/* ignore client certificate if any. */

586

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

503

gnutls_certificate_server_set_request(*session,

504

GNUTLS_CERT_IGNORE);

587

505

588

506

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

589

507

598

516

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

599

517

AvahiIfIndex if_index,

600

518

int af){

601

int ret, tcp_sd = -1;

519

int ret, tcp_sd;

602

520

ssize_t sret;

603

521

union {

604

522

struct sockaddr_in in;

605

523

struct sockaddr_in6 in6;

606

524

} to;

607

525

char *buffer = NULL;

608

char *decrypted_buffer = NULL;

526

char *decrypted_buffer;

609

527

size_t buffer_length = 0;

610

528

size_t buffer_capacity = 0;

529

ssize_t decrypted_buffer_size;

611

530

size_t written;

612

int retval = -1;

531

int retval = 0;

613

532

gnutls_session_t session;

614

533

int pf; /* Protocol family */

615

534

616

errno = 0;

617

618

if(quit_now){

619

errno = EINTR;

620

return -1;

621

}

622

623

535

switch(af){

624

536

case AF_INET6:

625

537

pf = PF_INET6;

629

541

break;

630

542

default:

631

543

fprintf(stderr, "Bad address family: %d\n", af);

632

errno = EINVAL;

633

544

return -1;

634

545

}

635

546

645

556

646

557

tcp_sd = socket(pf, SOCK_STREAM, 0);

647

558

if(tcp_sd < 0){

648

int e = errno;

649

perror_plus("socket");

650

errno = e;

651

goto mandos_end;

652

}

653

654

if(quit_now){

655

errno = EINTR;

656

goto mandos_end;

559

perror("socket");

560

return -1;

657

561

}

658

562

659

563

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

660

564

if(af == AF_INET6){

661

to.in6.sin6_family = (sa_family_t)af;

565

to.in6.sin6_family = (uint16_t)af;

662

566

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

663

567

} else { /* IPv4 */

664

568

to.in.sin_family = (sa_family_t)af;

665

569

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

666

570

}

667

571

if(ret < 0 ){

668

int e = errno;

669

perror_plus("inet_pton");

670

errno = e;

671

goto mandos_end;

572

perror("inet_pton");

573

return -1;

672

574

}

673

575

if(ret == 0){

674

int e = errno;

675

576

fprintf(stderr, "Bad address: %s\n", ip);

676

errno = e;

677

goto mandos_end;

577

return -1;

678

578

}

679

579

if(af == AF_INET6){

680

580

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

687

587

if(if_index == AVAHI_IF_UNSPEC){

688

588

fprintf(stderr, "An IPv6 link-local address is incomplete"

689

589

" without a network interface\n");

690

errno = EINVAL;

691

goto mandos_end;

590

return -1;

692

591

}

693

592

/* Set the network interface number as scope */

694

593

to.in6.sin6_scope_id = (uint32_t)if_index;

699

598

-Wunreachable-code */

700

599

}

701

600

702

if(quit_now){

703

errno = EINTR;

704

goto mandos_end;

705

}

706

707

601

if(debug){

708

602

if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){

709

603

char interface[IF_NAMESIZE];

710

604

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

711

perror_plus("if_indextoname");

605

perror("if_indextoname");

712

606

} else {

713

607

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

714

608

ip, interface, port);

728

622

sizeof(addrstr));

729

623

}

730

624

if(pcret == NULL){

731

perror_plus("inet_ntop");

625

perror("inet_ntop");

732

626

} else {

733

627

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

734

628

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

736

630

}

737

631

}

738

632

739

if(quit_now){

740

errno = EINTR;

741

goto mandos_end;

742

}

743

744

633

if(af == AF_INET6){

745

634

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

746

635

} else {

747

636

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

748

637

}

749

638

if(ret < 0){

750

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

751

int e = errno;

752

perror_plus("connect");

753

errno = e;

754

}

755

goto mandos_end;

756

}

757

758

if(quit_now){

759

errno = EINTR;

760

goto mandos_end;

639

perror("connect");

640

return -1;

761

641

}

762

642

763

643

const char *out = mandos_protocol_version;

767

647

ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,

768

648

out_size - written));

769

649

if(ret == -1){

770

int e = errno;

771

perror_plus("write");

772

errno = e;

650

perror("write");

651

retval = -1;

773

652

goto mandos_end;

774

653

}

775

654

written += (size_t)ret;

783

662

break;

784

663

}

785

664

}

786

787

if(quit_now){

788

errno = EINTR;

789

goto mandos_end;

790

}

791

665

}

792

666

793

667

if(debug){

794

668

fprintf(stderr, "Establishing TLS session with %s\n", ip);

795

669

}

796

670

797

if(quit_now){

798

errno = EINTR;

799

goto mandos_end;

800

}

801

802

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

803

671

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

804

672

805

if(quit_now){

806

errno = EINTR;

807

goto mandos_end;

808

}

809

810

do {

673

do{

811

674

ret = gnutls_handshake(session);

812

if(quit_now){

813

errno = EINTR;

814

goto mandos_end;

815

}

816

675

} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);

817

676

818

677

if(ret != GNUTLS_E_SUCCESS){

820

679

fprintf(stderr, "*** GnuTLS Handshake failed ***\n");

821

680

gnutls_perror(ret);

822

681

}

823

errno = EPROTO;

682

retval = -1;

824

683

goto mandos_end;

825

684

}

826

685

832

691

}

833

692

834

693

while(true){

835

836

if(quit_now){

837

errno = EINTR;

838

goto mandos_end;

839

}

840

841

694

buffer_capacity = incbuffer(&buffer, buffer_length,

842

695

buffer_capacity);

843

696

if(buffer_capacity == 0){

844

int e = errno;

845

perror_plus("incbuffer");

846

errno = e;

847

goto mandos_end;

848

}

849

850

if(quit_now){

851

errno = EINTR;

697

perror("incbuffer");

698

retval = -1;

852

699

goto mandos_end;

853

700

}

854

701

863

710

case GNUTLS_E_AGAIN:

864

711

break;

865

712

case GNUTLS_E_REHANDSHAKE:

866

do {

713

do{

867

714

ret = gnutls_handshake(session);

868

869

if(quit_now){

870

errno = EINTR;

871

goto mandos_end;

872

}

873

715

} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);

874

716

if(ret < 0){

875

717

fprintf(stderr, "*** GnuTLS Re-handshake failed ***\n");

876

718

gnutls_perror(ret);

877

errno = EPROTO;

719

retval = -1;

878

720

goto mandos_end;

879

721

}

880

722

break;

881

723

default:

882

724

fprintf(stderr, "Unknown error while reading data from"

883

725

" encrypted session with Mandos server\n");

726

retval = -1;

884

727

gnutls_bye(session, GNUTLS_SHUT_RDWR);

885

errno = EIO;

886

728

goto mandos_end;

887

729

}

888

730

} else {

894

736

fprintf(stderr, "Closing TLS session\n");

895

737

}

896

738

897

if(quit_now){

898

errno = EINTR;

899

goto mandos_end;

900

}

901

902

do {

903

ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);

904

if(quit_now){

905

errno = EINTR;

906

goto mandos_end;

907

}

908

} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);

739

gnutls_bye(session, GNUTLS_SHUT_RDWR);

909

740

910

741

if(buffer_length > 0){

911

ssize_t decrypted_buffer_size;

912

742

decrypted_buffer_size = pgp_packet_decrypt(buffer,

913

743

buffer_length,

914

744

&decrypted_buffer);

915

745

if(decrypted_buffer_size >= 0){

916

917

746

written = 0;

918

747

while(written < (size_t) decrypted_buffer_size){

919

if(quit_now){

920

errno = EINTR;

921

goto mandos_end;

922

}

923

924

748

ret = (int)fwrite(decrypted_buffer + written, 1,

925

749

(size_t)decrypted_buffer_size - written,

926

750

stdout);

927

751

if(ret == 0 and ferror(stdout)){

928

int e = errno;

929

752

if(debug){

930

753

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

931

754

strerror(errno));

932

755

}

933

errno = e;

934

goto mandos_end;

756

retval = -1;

757

break;

935

758

}

936

759

written += (size_t)ret;

937

760

}

938

retval = 0;

761

free(decrypted_buffer);

762

} else {

763

retval = -1;

939

764

}

765

} else {

766

retval = -1;

940

767

}

941

768

942

769

/* Shutdown procedure */

943

770

944

771

mandos_end:

945

{

946

int e = errno;

947

free(decrypted_buffer);

948

free(buffer);

949

if(tcp_sd >= 0){

950

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

951

}

952

if(ret == -1){

953

if(e == 0){

954

e = errno;

955

}

956

perror_plus("close");

957

}

958

gnutls_deinit(session);

959

errno = e;

960

if(quit_now){

961

errno = EINTR;

962

retval = -1;

963

}

772

free(buffer);

773

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

774

if(ret == -1){

775

perror("close");

964

776

}

777

gnutls_deinit(session);

965

778

return retval;

966

779

}

967

780

984

797

/* Called whenever a service has been resolved successfully or

985

798

timed out */

986

799

987

if(quit_now){

988

return;

989

}

990

991

800

switch(event){

992

801

default:

993

802

case AVAHI_RESOLVER_FAILURE:

1009

818

avahi_proto_to_af(proto));

1010

819

if(ret == 0){

1011

820

avahi_simple_poll_quit(mc.simple_poll);

1012

} else {

1013

ret = add_server(ip, port, interface,

1014

avahi_proto_to_af(proto));

1015

821

}

1016

822

}

1017

823

}

1033

839

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

1034

840

is removed from the LAN */

1035

841

1036

if(quit_now){

1037

return;

1038

}

1039

1040

842

switch(event){

1041

843

default:

1042

844

case AVAHI_BROWSER_FAILURE:

1052

854

the callback function is called the Avahi server will free the

1053

855

resolver for us. */

1054

856

1055

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

1056

name, type, domain, protocol, 0,

1057

resolve_callback, NULL) == NULL)

857

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

858

protocol, name, type, domain,

859

AVAHI_PROTO_INET6, 0,

860

resolve_callback, NULL)))

1058

861

fprintf(stderr, "Avahi: Failed to resolve service '%s': %s\n",

1059

862

name, avahi_strerror(avahi_server_errno(mc.server)));

1060

863

break;

1071

874

}

1072

875

}

1073

876

1074

/* Signal handler that stops main loop after SIGTERM */

1075

static void handle_sigterm(int sig){

877

sig_atomic_t quit_now = 0;

878

879

/* stop main loop after sigterm has been called */

880

static void handle_sigterm(__attribute__((unused)) int sig){

1076

881

if(quit_now){

1077

882

return;

1078

883

}

1079

884

quit_now = 1;

1080

signal_received = sig;

1081

885

int old_errno = errno;

1082

/* set main loop to exit */

1083

886

if(mc.simple_poll != NULL){

1084

887

avahi_simple_poll_quit(mc.simple_poll);

1085

888

}

1086

889

errno = old_errno;

1087

890

}

1088

891

1089

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

1090

int ret;

1091

1092

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

1093

if(s < 0){

1094

perror_plus("socket");

1095

return false;

1096

}

1097

strcpy(ifr->ifr_name, ifname);

1098

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1099

if(ret == -1){

1100

if(debug){

1101

perror_plus("ioctl SIOCGIFFLAGS");

1102

}

1103

return false;

1104

}

1105

return true;

1106

}

1107

1108

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

1109

1110

/* Reject the loopback device */

1111

if(ifr->ifr_flags & IFF_LOOPBACK){

1112

if(debug){

1113

fprintf(stderr, "Rejecting loopback interface \"%s\"\n",

1114

ifname);

1115

}

1116

return false;

1117

}

1118

/* Accept point-to-point devices only if connect_to is specified */

1119

if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){

1120

if(debug){

1121

fprintf(stderr, "Accepting point-to-point interface \"%s\"\n",

1122

ifname);

1123

}

1124

return true;

1125

}

1126

/* Otherwise, reject non-broadcast-capable devices */

1127

if(not (ifr->ifr_flags & IFF_BROADCAST)){

1128

if(debug){

1129

fprintf(stderr, "Rejecting non-broadcast interface \"%s\"\n",

1130

ifname);

1131

}

1132

return false;

1133

}

1134

/* Reject non-ARP interfaces (including dummy interfaces) */

1135

if(ifr->ifr_flags & IFF_NOARP){

1136

if(debug){

1137

fprintf(stderr, "Rejecting non-ARP interface \"%s\"\n", ifname);

1138

}

1139

return false;

1140

}

1141

1142

/* Accept this device */

1143

if(debug){

1144

fprintf(stderr, "Interface \"%s\" is good\n", ifname);

1145

}

1146

return true;

1147

}

1148

1149

/*

1150

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

1151

* corresponds to an acceptable network device.

1152

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

1153

*/

1154

int good_interface(const struct dirent *if_entry){

1155

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

1156

return 0;

1157

}

1158

1159

struct ifreq ifr;

1160

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

1161

if(debug){

1162

fprintf(stderr, "Failed to get flags for interface \"%s\"\n",

1163

if_entry->d_name);

1164

}

1165

return 0;

1166

}

1167

1168

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

1169

return 0;

1170

}

1171

return 1;

1172

}

1173

1174

/*

1175

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

1176

* corresponds to an acceptable network device which is up.

1177

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

1178

*/

1179

int up_interface(const struct dirent *if_entry){

1180

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

1181

return 0;

1182

}

1183

1184

struct ifreq ifr;

1185

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

1186

if(debug){

1187

fprintf(stderr, "Failed to get flags for interface \"%s\"\n",

1188

if_entry->d_name);

1189

}

1190

return 0;

1191

}

1192

1193

/* Reject down interfaces */

1194

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

1195

if(debug){

1196

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

1197

if_entry->d_name);

1198

}

1199

return 0;

1200

}

1201

1202

/* Reject non-running interfaces */

1203

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

1204

if(debug){

1205

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

1206

if_entry->d_name);

1207

}

1208

return 0;

1209

}

1210

1211

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

1212

return 0;

1213

}

1214

return 1;

1215

}

1216

1217

int notdotentries(const struct dirent *direntry){

1218

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

1219

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

1220

and (direntry->d_name[1] == '\0'

1221

or (direntry->d_name[1] == '.'

1222

and direntry->d_name[2] == '\0'))){

1223

return 0;

1224

}

1225

return 1;

1226

}

1227

1228

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

1229

int runnable_hook(const struct dirent *direntry){

1230

int ret;

1231

struct stat st;

1232

1233

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

1234

/* Empty name? */

1235

return 0;

1236

}

1237

1238

/* Save pointer to last character */

1239

char *end = strchr(direntry->d_name, '\0')-1;

1240

1241

if(*end == '~'){

1242

/* Backup name~ */

1243

return 0;

1244

}

1245

1246

if(((direntry->d_name)[0] == '#')

1247

and (*end == '#')){

1248

/* Temporary #name# */

1249

return 0;

1250

}

1251

1252

/* XXX more rules here */

1253

1254

ret = stat(direntry->d_name, &st);

1255

if(ret == -1){

1256

if(debug){

1257

perror_plus("Could not stat plugin");

1258

}

1259

return 0;

1260

}

1261

if(not (S_ISREG(st.st_mode))){

1262

/* Not a regular file */

1263

return 0;

1264

}

1265

if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){

1266

/* Not executable */

1267

return 0;

1268

}

1269

return 1;

1270

}

1271

1272

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1273

int ret;

1274

struct timespec now;

1275

struct timespec waited_time;

1276

intmax_t block_time;

1277

1278

while(true){

1279

if(mc.current_server == NULL){

1280

if (debug){

1281

fprintf(stderr,

1282

"Wait until first server is found. No timeout!\n");

1283

}

1284

ret = avahi_simple_poll_iterate(s, -1);

1285

} else {

1286

if (debug){

1287

fprintf(stderr, "Check current_server if we should run it,"

1288

" or wait\n");

1289

}

1290

/* the current time */

1291

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1292

if(ret == -1){

1293

perror_plus("clock_gettime");

1294

return -1;

1295

}

1296

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

1297

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

1298

waited_time.tv_sec = (now.tv_sec

1299

- mc.current_server->last_seen.tv_sec);

1300

waited_time.tv_nsec = (now.tv_nsec

1301

- mc.current_server->last_seen.tv_nsec);

1302

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

1303

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

1304

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

1305

block_time = ((retry_interval

1306

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

1307

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

1308

1309

if (debug){

1310

fprintf(stderr, "Blocking for %" PRIdMAX " ms\n", block_time);

1311

}

1312

1313

if(block_time <= 0){

1314

ret = start_mandos_communication(mc.current_server->ip,

1315

mc.current_server->port,

1316

mc.current_server->if_index,

1317

mc.current_server->af);

1318

if(ret == 0){

1319

avahi_simple_poll_quit(mc.simple_poll);

1320

return 0;

1321

}

1322

ret = clock_gettime(CLOCK_MONOTONIC,

1323

&mc.current_server->last_seen);

1324

if(ret == -1){

1325

perror_plus("clock_gettime");

1326

return -1;

1327

}

1328

mc.current_server = mc.current_server->next;

1329

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

1330

servers, but don't block */

1331

}

1332

1333

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

1334

}

1335

if(ret != 0){

1336

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

1337

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

1338

}

1339

}

1340

}

1341

}

1342

1343

892

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

1344

893

AvahiSServiceBrowser *sb = NULL;

1345

894

int error;

1347

896

intmax_t tmpmax;

1348

897

char *tmp;

1349

898

int exitcode = EXIT_SUCCESS;

1350

const char *interface = "";

899

const char *interface = "eth0";

1351

900

struct ifreq network;

1352

int sd = -1;

1353

bool take_down_interface = false;

901

int sd;

1354

902

uid_t uid;

1355

903

gid_t gid;

904

char *connect_to = NULL;

1356

905

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

1357

906

bool tempdir_created = false;

1358

907

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1359

908

const char *seckey = PATHDIR "/" SECKEY;

1360

909

const char *pubkey = PATHDIR "/" PUBKEY;

1361

910

911

/* Initialize Mandos context */

912

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

913

.dh_bits = 1024, .priority = "SECURE256"

914

":!CTYPE-X.509:+CTYPE-OPENPGP" };

1362

915

bool gnutls_initialized = false;

1363

916

bool gpgme_initialized = false;

1364

917

float delay = 2.5f;

1365

double retry_interval = 10; /* 10s between trying a server and

1366

retrying the same server again */

1367

918

1368

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

919

struct sigaction old_sigterm_action;

1369

920

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

1370

921

1371

uid = getuid();

1372

gid = getgid();

1373

1374

/* Lower any group privileges we might have, just to be safe */

1375

errno = 0;

1376

ret = setgid(gid);

1377

if(ret == -1){

1378

perror_plus("setgid");

1379

}

1380

1381

/* Lower user privileges (temporarily) */

1382

errno = 0;

1383

ret = seteuid(uid);

1384

if(ret == -1){

1385

perror_plus("seteuid");

1386

}

1387

1388

if(quit_now){

1389

goto end;

1390

}

1391

1392

922

{

1393

923

struct argp_option options[] = {

1394

924

{ .name = "debug", .key = 128,

1423

953

.arg = "SECONDS",

1424

954

.doc = "Maximum delay to wait for interface startup",

1425

955

.group = 2 },

1426

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

1427

.arg = "SECONDS",

1428

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

1429

.group = 2 },

1430

/*

1431

* These reproduce what we would get without ARGP_NO_HELP

1432

*/

1433

{ .name = "help", .key = '?',

1434

.doc = "Give this help list", .group = -1 },

1435

{ .name = "usage", .key = -3,

1436

.doc = "Give a short usage message", .group = -1 },

1437

{ .name = "version", .key = 'V',

1438

.doc = "Print program version", .group = -1 },

1439

956

{ .name = NULL }

1440

957

};

1441

958

1442

959

error_t parse_opt(int key, char *arg,

1443

960

struct argp_state *state){

1444

errno = 0;

1445

961

switch(key){

1446

962

case 128: /* --debug */

1447

963

debug = true;

1463

979

tmpmax = strtoimax(arg, &tmp, 10);

1464

980

if(errno != 0 or tmp == arg or *tmp != '\0'

1465

981

or tmpmax != (typeof(mc.dh_bits))tmpmax){

1466

argp_error(state, "Bad number of DH bits");

982

fprintf(stderr, "Bad number of DH bits\n");

983

exit(EXIT_FAILURE);

1467

984

}

1468

985

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

1469

986

break;

1474

991

errno = 0;

1475

992

delay = strtof(arg, &tmp);

1476

993

if(errno != 0 or tmp == arg or *tmp != '\0'){

1477

argp_error(state, "Bad delay");

1478

}

1479

case 132: /* --retry */

1480

errno = 0;

1481

retry_interval = strtod(arg, &tmp);

1482

if(errno != 0 or tmp == arg or *tmp != '\0'

1483

or (retry_interval * 1000) > INT_MAX

1484

or retry_interval < 0){

1485

argp_error(state, "Bad retry interval");

994

fprintf(stderr, "Bad delay\n");

995

exit(EXIT_FAILURE);

1486

996

}

1487

997

break;

1488

/*

1489

* These reproduce what we would get without ARGP_NO_HELP

1490

*/

1491

case '?': /* --help */

1492

argp_state_help(state, state->out_stream,

1493

(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)

1494

& ~(unsigned int)ARGP_HELP_EXIT_OK);

1495

case -3: /* --usage */

1496

argp_state_help(state, state->out_stream,

1497

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1498

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

1499

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

1500

exit(argp_err_exit_status);

998

case ARGP_KEY_ARG:

999

argp_usage(state);

1000

case ARGP_KEY_END:

1501

1001

break;

1502

1002

default:

1503

1003

return ARGP_ERR_UNKNOWN;

1504

1004

}

1505

return errno;

1005

return 0;

1506

1006

}

1507

1007

1508

1008

struct argp argp = { .options = options, .parser = parse_opt,

1509

1009

.args_doc = "",

1510

1010

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

1511

1011

" passwords from a Mandos server" };

1512

ret = argp_parse(&argp, argc, argv,

1513

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1514

switch(ret){

1515

case 0:

1516

break;

1517

case ENOMEM:

1518

default:

1519

errno = ret;

1520

perror_plus("argp_parse");

1521

exitcode = EX_OSERR;

1522

goto end;

1523

case EINVAL:

1524

exitcode = EX_USAGE;

1525

goto end;

1526

}

1527

}

1528

1529

{

1530

/* Work around Debian bug #633582:

1531

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

1532

struct stat st;

1533

1534

/* Re-raise priviliges */

1535

errno = 0;

1536

ret = seteuid(0);

1537

if(ret == -1){

1538

perror_plus("seteuid");

1539

}

1540

1541

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

1542

int seckey_fd = open(seckey, O_RDONLY);

1543

if(seckey_fd == -1){

1544

perror_plus("open");

1545

} else {

1546

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

1547

if(ret == -1){

1548

perror_plus("fstat");

1549

} else {

1550

if(S_ISREG(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){

1551

ret = fchown(seckey_fd, uid, gid);

1552

if(ret == -1){

1553

perror_plus("fchown");

1554

}

1555

}

1556

}

1557

TEMP_FAILURE_RETRY(close(seckey_fd));

1558

}

1559

}

1560

1561

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

1562

int pubkey_fd = open(pubkey, O_RDONLY);

1563

if(pubkey_fd == -1){

1564

perror_plus("open");

1565

} else {

1566

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

1567

if(ret == -1){

1568

perror_plus("fstat");

1569

} else {

1570

if(S_ISREG(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){

1571

ret = fchown(pubkey_fd, uid, gid);

1572

if(ret == -1){

1573

perror_plus("fchown");

1574

}

1575

}

1576

}

1577

TEMP_FAILURE_RETRY(close(pubkey_fd));

1578

}

1579

}

1580

1581

/* Lower privileges */

1582

errno = 0;

1583

ret = seteuid(uid);

1584

if(ret == -1){

1585

perror_plus("seteuid");

1586

}

1587

}

1588

1589

/* Find network hooks and run them */

1590

{

1591

struct dirent **direntries;

1592

struct dirent *direntry;

1593

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

1594

alphasort);

1595

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

1596

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

1597

direntry = direntries[0];

1598

char *fullname = NULL;

1599

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

1600

direntry->d_name);

1601

if(ret < 0){

1602

perror_plus("asprintf");

1603

continue;

1604

}

1605

pid_t hook_pid = fork();

1606

if(hook_pid == 0){

1607

/* Child */

1608

dup2(devnull, STDIN_FILENO);

1609

close(devnull);

1610

dup2(STDERR_FILENO, STDOUT_FILENO);

1611

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

1612

if(ret == -1){

1613

perror_plus("setenv");

1614

exit(1);

1615

}

1616

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

1617

if(ret == -1){

1618

perror_plus("setenv");

1619

exit(1);

1620

}

1621

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

1622

if(ret == -1){

1623

perror_plus("setenv");

1624

exit(1);

1625

}

1626

char *delaystring;

1627

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

1628

if(ret == -1){

1629

perror_plus("asprintf");

1630

exit(1);

1631

}

1632

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

1633

if(ret == -1){

1634

free(delaystring);

1635

perror_plus("setenv");

1636

exit(1);

1637

}

1638

free(delaystring);

1639

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

1640

perror_plus("execl");

1641

}

1642

free(fullname);

1643

if(quit_now){

1644

goto end;

1645

}

1646

}

1647

close(devnull);

1012

ret = argp_parse(&argp, argc, argv, 0, 0, NULL);

1013

if(ret == ARGP_ERR_UNKNOWN){

1014

fprintf(stderr, "Unknown error while parsing arguments\n");

1015

exitcode = EXIT_FAILURE;

1016

goto end;

1017

}

1648

1018

}

1649

1019

1650

1020

if(not debug){

1651

1021

avahi_set_log_function(empty_log);

1652

1022

}

1653

1023

1654

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

1655

struct dirent **direntries;

1656

/* First look for interfaces that are up */

1657

ret = scandir(sys_class_net, &direntries, up_interface,

1658

alphasort);

1659

if(ret == 0){

1660

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

1661

free(direntries);

1662

ret = scandir(sys_class_net, &direntries, good_interface,

1663

alphasort);

1664

}

1665

if(ret >= 1){

1666

/* Pick the first interface returned */

1667

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

1668

if(debug){

1669

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

1670

}

1671

if(interface == NULL){

1672

perror_plus("malloc");

1673

free(direntries);

1674

exitcode = EXIT_FAILURE;

1675

goto end;

1676

}

1677

free(direntries);

1678

} else {

1679

free(direntries);

1680

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

1681

exitcode = EXIT_FAILURE;

1682

goto end;

1683

}

1684

}

1685

1686

1024

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

1687

1025

from the signal handler */

1688

1026

/* Initialize the pseudo-RNG for Avahi */

1690

1028

mc.simple_poll = avahi_simple_poll_new();

1691

1029

if(mc.simple_poll == NULL){

1692

1030

fprintf(stderr, "Avahi: Failed to create simple poll object.\n");

1693

exitcode = EX_UNAVAILABLE;

1031

exitcode = EXIT_FAILURE;

1694

1032

goto end;

1695

1033

}

1696

1034

1697

1035

sigemptyset(&sigterm_action.sa_mask);

1698

1036

ret = sigaddset(&sigterm_action.sa_mask, SIGINT);

1699

1037

if(ret == -1){

1700

perror_plus("sigaddset");

1701

exitcode = EX_OSERR;

1038

perror("sigaddset");

1039

exitcode = EXIT_FAILURE;

1702

1040

goto end;

1703

1041

}

1704

1042

ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);

1705

1043

if(ret == -1){

1706

perror_plus("sigaddset");

1707

exitcode = EX_OSERR;

1044

perror("sigaddset");

1045

exitcode = EXIT_FAILURE;

1708

1046

goto end;

1709

1047

}

1710

1048

ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);

1711

1049

if(ret == -1){

1712

perror_plus("sigaddset");

1713

exitcode = EX_OSERR;

1714

goto end;

1715

}

1716

/* Need to check if the handler is SIG_IGN before handling:

1717

| [[info:libc:Initial Signal Actions]] |

1718

| [[info:libc:Basic Signal Handling]] |

1719

*/

1720

ret = sigaction(SIGINT, NULL, &old_sigterm_action);

1721

if(ret == -1){

1722

perror_plus("sigaction");

1723

return EX_OSERR;

1724

}

1725

if(old_sigterm_action.sa_handler != SIG_IGN){

1726

ret = sigaction(SIGINT, &sigterm_action, NULL);

1727

if(ret == -1){

1728

perror_plus("sigaction");

1729

exitcode = EX_OSERR;

1730

goto end;

1731

}

1732

}

1733

ret = sigaction(SIGHUP, NULL, &old_sigterm_action);

1734

if(ret == -1){

1735

perror_plus("sigaction");

1736

return EX_OSERR;

1737

}

1738

if(old_sigterm_action.sa_handler != SIG_IGN){

1739

ret = sigaction(SIGHUP, &sigterm_action, NULL);

1740

if(ret == -1){

1741

perror_plus("sigaction");

1742

exitcode = EX_OSERR;

1743

goto end;

1744

}

1745

}

1746

ret = sigaction(SIGTERM, NULL, &old_sigterm_action);

1747

if(ret == -1){

1748

perror_plus("sigaction");

1749

return EX_OSERR;

1750

}

1751

if(old_sigterm_action.sa_handler != SIG_IGN){

1752

ret = sigaction(SIGTERM, &sigterm_action, NULL);

1753

if(ret == -1){

1754

perror_plus("sigaction");

1755

exitcode = EX_OSERR;

1756

goto end;

1757

}

1758

}

1050

perror("sigaddset");

1051

exitcode = EXIT_FAILURE;

1052

goto end;

1053

}

1054

ret = sigaction(SIGTERM, &sigterm_action, &old_sigterm_action);

1055

if(ret == -1){

1056

perror("sigaction");

1057

exitcode = EXIT_FAILURE;

1058

goto end;

1059

}

1759

1060

1760

1061

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

1761

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

1762

if_index = (AvahiIfIndex) if_nametoindex(interface);

1763

if(if_index == 0){

1764

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

1765

exitcode = EX_UNAVAILABLE;

1766

goto end;

1767

}

1768

1769

if(quit_now){

1770

goto end;

1771

}

1772

1773

/* Re-raise priviliges */

1774

errno = 0;

1775

ret = seteuid(0);

1776

if(ret == -1){

1777

perror_plus("seteuid");

1778

}

1779

1062

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

1780

1063

#ifdef __linux__

1781

1064

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1782

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

1065

messages to mess up the prompt */

1783

1066

ret = klogctl(8, NULL, 5);

1784

1067

bool restore_loglevel = true;

1785

1068

if(ret == -1){

1786

1069

restore_loglevel = false;

1787

perror_plus("klogctl");

1070

perror("klogctl");

1788

1071

}

1789

1072

#endif /* __linux__ */

1790

1073

1791

1074

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1792

1075

if(sd < 0){

1793

perror_plus("socket");

1794

exitcode = EX_OSERR;

1076

perror("socket");

1077

exitcode = EXIT_FAILURE;

1795

1078

#ifdef __linux__

1796

1079

if(restore_loglevel){

1797

1080

ret = klogctl(7, NULL, 0);

1798

1081

if(ret == -1){

1799

perror_plus("klogctl");

1082

perror("klogctl");

1800

1083

}

1801

1084

}

1802

1085

#endif /* __linux__ */

1803

/* Lower privileges */

1804

errno = 0;

1805

ret = seteuid(uid);

1806

if(ret == -1){

1807

perror_plus("seteuid");

1808

}

1809

1086

goto end;

1810

1087

}

1811

1088

strcpy(network.ifr_name, interface);

1812

1089

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

1813

1090

if(ret == -1){

1814

perror_plus("ioctl SIOCGIFFLAGS");

1091

perror("ioctl SIOCGIFFLAGS");

1815

1092

#ifdef __linux__

1816

1093

if(restore_loglevel){

1817

1094

ret = klogctl(7, NULL, 0);

1818

1095

if(ret == -1){

1819

perror_plus("klogctl");

1096

perror("klogctl");

1820

1097

}

1821

1098

}

1822

1099

#endif /* __linux__ */

1823

exitcode = EX_OSERR;

1824

/* Lower privileges */

1825

errno = 0;

1826

ret = seteuid(uid);

1827

if(ret == -1){

1828

perror_plus("seteuid");

1829

}

1100

exitcode = EXIT_FAILURE;

1830

1101

goto end;

1831

1102

}

1832

1103

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

1833

1104

network.ifr_flags |= IFF_UP;

1834

take_down_interface = true;

1835

1105

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

1836

1106

if(ret == -1){

1837

take_down_interface = false;

1838

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1839

exitcode = EX_OSERR;

1107

perror("ioctl SIOCSIFFLAGS");

1108

exitcode = EXIT_FAILURE;

1840

1109

#ifdef __linux__

1841

1110

if(restore_loglevel){

1842

1111

ret = klogctl(7, NULL, 0);

1843

1112

if(ret == -1){

1844

perror_plus("klogctl");

1113

perror("klogctl");

1845

1114

}

1846

1115

}

1847

1116

#endif /* __linux__ */

1848

/* Lower privileges */

1849

errno = 0;

1850

ret = seteuid(uid);

1851

if(ret == -1){

1852

perror_plus("seteuid");

1853

}

1854

1117

goto end;

1855

1118

}

1856

1119

}

1857

/* Sleep checking until interface is running.

1858

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

1120

/* sleep checking until interface is running */

1859

1121

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

1860

1122

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

1861

1123

if(ret == -1){

1862

perror_plus("ioctl SIOCGIFFLAGS");

1124

perror("ioctl SIOCGIFFLAGS");

1863

1125

} else if(network.ifr_flags & IFF_RUNNING){

1864

1126

break;

1865

1127

}

1866

1128

struct timespec sleeptime = { .tv_nsec = 250000000 };

1867

1129

ret = nanosleep(&sleeptime, NULL);

1868

1130

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

1869

perror_plus("nanosleep");

1131

perror("nanosleep");

1870

1132

}

1871

1133

}

1872

if(not take_down_interface){

1873

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

1874

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

1875

if(ret == -1){

1876

perror_plus("close");

1877

}

1134

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

1135

if(ret == -1){

1136

perror("close");

1878

1137

}

1879

1138

#ifdef __linux__

1880

1139

if(restore_loglevel){

1881

1140

/* Restores kernel loglevel to default */

1882

1141

ret = klogctl(7, NULL, 0);

1883

1142

if(ret == -1){

1884

perror_plus("klogctl");

1143

perror("klogctl");

1885

1144

}

1886

1145

}

1887

1146

#endif /* __linux__ */

1888

/* Lower privileges */

1889

errno = 0;

1890

if(take_down_interface){

1891

/* Lower privileges */

1892

ret = seteuid(uid);

1893

if(ret == -1){

1894

perror_plus("seteuid");

1895

}

1896

} else {

1897

/* Lower privileges permanently */

1898

ret = setuid(uid);

1899

if(ret == -1){

1900

perror_plus("setuid");

1901

}

1902

}

1903

}

1904

1905

if(quit_now){

1906

goto end;

1147

}

1148

1149

uid = getuid();

1150

gid = getgid();

1151

1152

errno = 0;

1153

setgid(gid);

1154

if(ret == -1){

1155

perror("setgid");

1156

}

1157

1158

ret = setuid(uid);

1159

if(ret == -1){

1160

perror("setuid");

1907

1161

}

1908

1162

1909

1163

ret = init_gnutls_global(pubkey, seckey);

1910

1164

if(ret == -1){

1911

1165

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

1912

exitcode = EX_UNAVAILABLE;

1166

exitcode = EXIT_FAILURE;

1913

1167

goto end;

1914

1168

} else {

1915

1169

gnutls_initialized = true;

1916

1170

}

1917

1171

1918

if(quit_now){

1919

goto end;

1920

}

1921

1922

1172

if(mkdtemp(tempdir) == NULL){

1923

perror_plus("mkdtemp");

1173

perror("mkdtemp");

1924

1174

goto end;

1925

1175

}

1926

1176

tempdir_created = true;

1927

1177

1928

if(quit_now){

1929

goto end;

1930

}

1931

1932

1178

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

1933

1179

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

1934

exitcode = EX_UNAVAILABLE;

1180

exitcode = EXIT_FAILURE;

1935

1181

goto end;

1936

1182

} else {

1937

1183

gpgme_initialized = true;

1938

1184

}

1939

1185

1940

if(quit_now){

1941

goto end;

1186

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

1187

if_index = (AvahiIfIndex) if_nametoindex(interface);

1188

if(if_index == 0){

1189

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

1190

exitcode = EXIT_FAILURE;

1191

goto end;

1192

}

1942

1193

}

1943

1194

1944

1195

if(connect_to != NULL){

1947

1198

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

1948

1199

if(address == NULL){

1949

1200

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

1950

exitcode = EX_USAGE;

1951

goto end;

1952

}

1953

1954

if(quit_now){

1955

goto end;

1956

}

1957

1201

exitcode = EXIT_FAILURE;

1202

goto end;

1203

}

1958

1204

uint16_t port;

1959

1205

errno = 0;

1960

1206

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

1961

1207

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

1962

1208

or tmpmax != (uint16_t)tmpmax){

1963

1209

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

1964

exitcode = EX_USAGE;

1965

goto end;

1966

}

1967

1968

if(quit_now){

1969

goto end;

1970

}

1971

1210

exitcode = EXIT_FAILURE;

1211

goto end;

1212

}

1972

1213

port = (uint16_t)tmpmax;

1973

1214

*address = '\0';

1215

address = connect_to;

1974

1216

/* Colon in address indicates IPv6 */

1975

1217

int af;

1976

if(strchr(connect_to, ':') != NULL){

1218

if(strchr(address, ':') != NULL){

1977

1219

af = AF_INET6;

1978

/* Accept [] around IPv6 address - see RFC 5952 */

1979

if(connect_to[0] == '[' and address[-1] == ']')

1980

{

1981

connect_to++;

1982

address[-1] = '\0';

1983

}

1984

1220

} else {

1985

1221

af = AF_INET;

1986

1222

}

1987

address = connect_to;

1988

1989

if(quit_now){

1990

goto end;

1991

}

1992

1993

while(not quit_now){

1994

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

1995

if(quit_now or ret == 0){

1996

break;

1997

}

1998

if(debug){

1999

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

2000

(int)retry_interval);

2001

}

2002

sleep((int)retry_interval);

2003

}

2004

2005

if (not quit_now){

1223

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

1224

if(ret < 0){

1225

exitcode = EXIT_FAILURE;

1226

} else {

2006

1227

exitcode = EXIT_SUCCESS;

2007

1228

}

1229

goto end;

1230

}

2008

1231

2009

goto end;

2010

}

2011

2012

if(quit_now){

2013

goto end;

2014

}

2015

2016

1232

{

2017

1233

AvahiServerConfig config;

2018

1234

/* Do not publish any local Zeroconf records */

2035

1251

if(mc.server == NULL){

2036

1252

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

2037

1253

avahi_strerror(error));

2038

exitcode = EX_UNAVAILABLE;

2039

goto end;

2040

}

2041

2042

if(quit_now){

1254

exitcode = EXIT_FAILURE;

2043

1255

goto end;

2044

1256

}

2045

1257

2046

1258

/* Create the Avahi service browser */

2047

1259

sb = avahi_s_service_browser_new(mc.server, if_index,

2048

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

1260

AVAHI_PROTO_INET6, "_mandos._tcp",

2049

1261

NULL, 0, browse_callback, NULL);

2050

1262

if(sb == NULL){

2051

1263

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

2052

1264

avahi_strerror(avahi_server_errno(mc.server)));

2053

exitcode = EX_UNAVAILABLE;

2054

goto end;

2055

}

2056

2057

if(quit_now){

1265

exitcode = EXIT_FAILURE;

2058

1266

goto end;

2059

1267

}

2060

1268

2063

1271

if(debug){

2064

1272

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

2065

1273

}

2066

2067

ret = avahi_loop_with_timeout(mc.simple_poll,

2068

(int)(retry_interval * 1000));

2069

if(debug){

2070

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

2071

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

2072

}

1274

1275

avahi_simple_poll_loop(mc.simple_poll);

2073

1276

2074

1277

end:

2075

1278

2096

1299

if(gpgme_initialized){

2097

1300

gpgme_release(mc.ctx);

2098

1301

}

2099

2100

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

2101

has seen */

2102

if(mc.current_server != NULL){

2103

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

2104

while(mc.current_server != NULL){

2105

server *next = mc.current_server->next;

2106

free(mc.current_server);

2107

mc.current_server = next;

2108

}

2109

}

2110

2111

/* XXX run network hooks "stop" here */

2112

2113

/* Take down the network interface */

2114

if(take_down_interface){

2115

/* Re-raise priviliges */

2116

errno = 0;

2117

ret = seteuid(0);

2118

if(ret == -1){

2119

perror_plus("seteuid");

2120

}

2121

if(geteuid() == 0){

2122

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

2123

if(ret == -1){

2124

perror_plus("ioctl SIOCGIFFLAGS");

2125

} else if(network.ifr_flags & IFF_UP) {

2126

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

2127

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

2128

if(ret == -1){

2129

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2130

}

2131

}

2132

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

2133

if(ret == -1){

2134

perror_plus("close");

2135

}

2136

/* Lower privileges permanently */

2137

errno = 0;

2138

ret = setuid(uid);

2139

if(ret == -1){

2140

perror_plus("setuid");

2141

}

2142

}

2143

}

2144

2145

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

1302

1303

/* Removes the temp directory used by GPGME */

2146

1304

if(tempdir_created){

2147

struct dirent **direntries = NULL;

2148

struct dirent *direntry = NULL;

2149

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

2150

alphasort);

2151

if (numentries > 0){

2152

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

2153

direntry = direntries[i];

1305

DIR *d;

1306

struct dirent *direntry;

1307

d = opendir(tempdir);

1308

if(d == NULL){

1309

if(errno != ENOENT){

1310

perror("opendir");

1311

}

1312

} else {

1313

while(true){

1314

direntry = readdir(d);

1315

if(direntry == NULL){

1316

break;

1317

}

1318

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

1319

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

1320

and (direntry->d_name[1] == '\0'

1321

or (direntry->d_name[1] == '.'

1322

and direntry->d_name[2] == '\0'))){

1323

continue;

1324

}

2154

1325

char *fullname = NULL;

2155

1326

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

2156

1327

direntry->d_name);

2157

1328

if(ret < 0){

2158

perror_plus("asprintf");

1329

perror("asprintf");

2159

1330

continue;

2160

1331

}

2161

1332

ret = remove(fullname);

2165

1336

}

2166

1337

free(fullname);

2167

1338

}

2168

}

2169

2170

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

2171

free(direntries);

2172

if (numentries == -1){

2173

perror_plus("scandir");

1339

closedir(d);

2174

1340

}

2175

1341

ret = rmdir(tempdir);

2176

1342

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

2177

perror_plus("rmdir");

2178

}

2179

}

2180

2181

if(quit_now){

2182

sigemptyset(&old_sigterm_action.sa_mask);

2183

old_sigterm_action.sa_handler = SIG_DFL;

2184

ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,

2185

&old_sigterm_action,

2186

NULL));

2187

if(ret == -1){

2188

perror_plus("sigaction");

2189

}

2190

do {

2191

ret = raise(signal_received);

2192

} while(ret != 0 and errno == EINTR);

2193

if(ret != 0){

2194

perror_plus("raise");

2195

abort();

2196

}

2197

TEMP_FAILURE_RETRY(pause());

1343

perror("rmdir");

1344

}

2198

1345

}

2199

1346

2200

1347

return exitcode;