/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() */

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() */

127

120

bool debug = false;

128

121

static const char mandos_protocol_version[] = "1";

129

122

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

130

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

131

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

132

char *connect_to = NULL;

133

134

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

135

typedef struct server{

136

const char *ip;

137

uint16_t port;

138

AvahiIfIndex if_index;

139

int af;

140

struct timespec last_seen;

141

struct server *next;

142

struct server *prev;

143

} server;

123

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

144

124

145

125

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

146

126

typedef struct {

151

131

gnutls_dh_params_t dh_params;

152

132

const char *priority;

153

133

gpgme_ctx_t ctx;

154

server *current_server;

155

134

} mandos_context;

156

135

157

136

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

158

137

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

159

138

.dh_bits = 1024, .priority = "SECURE256"

160

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

161

.current_server = NULL };

162

163

sig_atomic_t quit_now = 0;

164

int signal_received = 0;

165

166

/* Function to use when printing errors */

167

void perror_plus(const char *print_text){

168

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

169

program_invocation_short_name);

170

perror(print_text);

171

}

139

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

172

140

173

141

/*

174

142

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

187

155

return buffer_capacity;

188

156

}

189

157

190

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

191

int add_server(const char *ip, uint16_t port,

192

AvahiIfIndex if_index,

193

int af){

194

int ret;

195

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

196

if(new_server == NULL){

197

perror_plus("malloc");

198

return -1;

199

}

200

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

201

.port = port,

202

.if_index = if_index,

203

.af = af };

204

if(new_server->ip == NULL){

205

perror_plus("strdup");

206

return -1;

207

}

208

/* Special case of first server */

209

if (mc.current_server == NULL){

210

new_server->next = new_server;

211

new_server->prev = new_server;

212

mc.current_server = new_server;

213

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

214

} else {

215

new_server->next = mc.current_server;

216

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

217

new_server->prev->next = new_server;

218

mc.current_server->prev = new_server;

219

}

220

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

221

if(ret == -1){

222

perror_plus("clock_gettime");

223

return -1;

224

}

225

return 0;

226

}

227

228

158

/*

229

159

* Initialize GPGME.

230

160

*/

231

161

static bool init_gpgme(const char *seckey,

232

162

const char *pubkey, const char *tempdir){

163

int ret;

233

164

gpgme_error_t rc;

234

165

gpgme_engine_info_t engine_info;

235

166

238

169

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

239

170

*/

240

171

bool import_key(const char *filename){

241

int ret;

242

172

int fd;

243

173

gpgme_data_t pgp_data;

244

174

245

175

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

246

176

if(fd == -1){

247

perror_plus("open");

177

perror("open");

248

178

return false;

249

179

}

250

180

264

194

265

195

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

266

196

if(ret == -1){

267

perror_plus("close");

197

perror("close");

268

198

}

269

199

gpgme_data_release(pgp_data);

270

200

return true;

283

213

return false;

284

214

}

285

215

286

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

216

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

287

217

rc = gpgme_get_engine_info(&engine_info);

288

218

if(rc != GPG_ERR_NO_ERROR){

289

219

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

315

245

return false;

316

246

}

317

247

318

return true;

248

return true;

319

249

}

320

250

321

251

/*

375

305

}

376

306

gpgme_recipient_t recipient;

377

307

recipient = result->recipients;

378

while(recipient != NULL){

379

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

380

gpgme_pubkey_algo_name(recipient->pubkey_algo));

381

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

382

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

383

recipient->status == GPG_ERR_NO_SECKEY

384

? "No" : "Yes");

385

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

}

386

318

}

387

319

}

388

320

}

395

327

396

328

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

397

329

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

398

perror_plus("gpgme_data_seek");

330

perror("gpgme_data_seek");

399

331

plaintext_length = -1;

400

332

goto decrypt_end;

401

333

}

406

338

(size_t)plaintext_length,

407

339

plaintext_capacity);

408

340

if(plaintext_capacity == 0){

409

perror_plus("incbuffer");

341

perror("incbuffer");

410

342

plaintext_length = -1;

411

343

goto decrypt_end;

412

344

}

419

351

break;

420

352

}

421

353

if(ret < 0){

422

perror_plus("gpgme_data_read");

354

perror("gpgme_data_read");

423

355

plaintext_length = -1;

424

356

goto decrypt_end;

425

357

}

482

414

}

483

415

484

416

/* OpenPGP credentials */

485

ret = gnutls_certificate_allocate_credentials(&mc.cred);

417

gnutls_certificate_allocate_credentials(&mc.cred);

486

418

if(ret != GNUTLS_E_SUCCESS){

487

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

419

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

420

from

421

-Wunreachable-code

422

*/

488

423

safer_gnutls_strerror(ret));

489

424

gnutls_global_deinit();

490

425

return -1;

537

472

static int init_gnutls_session(gnutls_session_t *session){

538

473

int ret;

539

474

/* GnuTLS session creation */

540

do {

541

ret = gnutls_init(session, GNUTLS_SERVER);

542

if(quit_now){

543

return -1;

544

}

545

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

475

ret = gnutls_init(session, GNUTLS_SERVER);

546

476

if(ret != GNUTLS_E_SUCCESS){

547

477

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

548

478

safer_gnutls_strerror(ret));

550

480

551

481

{

552

482

const char *err;

553

do {

554

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

555

if(quit_now){

556

gnutls_deinit(*session);

557

return -1;

558

}

559

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

483

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

560

484

if(ret != GNUTLS_E_SUCCESS){

561

485

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

562

486

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

566

490

}

567

491

}

568

492

569

do {

570

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

571

mc.cred);

572

if(quit_now){

573

gnutls_deinit(*session);

574

return -1;

575

}

576

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

493

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

494

mc.cred);

577

495

if(ret != GNUTLS_E_SUCCESS){

578

496

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

579

497

safer_gnutls_strerror(ret));

582

500

}

583

501

584

502

/* ignore client certificate if any. */

585

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

503

gnutls_certificate_server_set_request(*session,

504

GNUTLS_CERT_IGNORE);

586

505

587

506

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

588

507

597

516

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

598

517

AvahiIfIndex if_index,

599

518

int af){

600

int ret, tcp_sd = -1;

519

int ret, tcp_sd;

601

520

ssize_t sret;

602

521

union {

603

522

struct sockaddr_in in;

604

523

struct sockaddr_in6 in6;

605

524

} to;

606

525

char *buffer = NULL;

607

char *decrypted_buffer = NULL;

526

char *decrypted_buffer;

608

527

size_t buffer_length = 0;

609

528

size_t buffer_capacity = 0;

529

ssize_t decrypted_buffer_size;

610

530

size_t written;

611

int retval = -1;

531

int retval = 0;

612

532

gnutls_session_t session;

613

533

int pf; /* Protocol family */

614

534

615

errno = 0;

616

617

if(quit_now){

618

errno = EINTR;

619

return -1;

620

}

621

622

535

switch(af){

623

536

case AF_INET6:

624

537

pf = PF_INET6;

628

541

break;

629

542

default:

630

543

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

631

errno = EINVAL;

632

544

return -1;

633

545

}

634

546

644

556

645

557

tcp_sd = socket(pf, SOCK_STREAM, 0);

646

558

if(tcp_sd < 0){

647

int e = errno;

648

perror_plus("socket");

649

errno = e;

650

goto mandos_end;

651

}

652

653

if(quit_now){

654

errno = EINTR;

655

goto mandos_end;

559

perror("socket");

560

return -1;

656

561

}

657

562

658

563

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

659

564

if(af == AF_INET6){

660

to.in6.sin6_family = (sa_family_t)af;

565

to.in6.sin6_family = (uint16_t)af;

661

566

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

662

567

} else { /* IPv4 */

663

568

to.in.sin_family = (sa_family_t)af;

664

569

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

665

570

}

666

571

if(ret < 0 ){

667

int e = errno;

668

perror_plus("inet_pton");

669

errno = e;

670

goto mandos_end;

572

perror("inet_pton");

573

return -1;

671

574

}

672

575

if(ret == 0){

673

int e = errno;

674

576

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

675

errno = e;

676

goto mandos_end;

577

return -1;

677

578

}

678

579

if(af == AF_INET6){

679

580

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

686

587

if(if_index == AVAHI_IF_UNSPEC){

687

588

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

688

589

" without a network interface\n");

689

errno = EINVAL;

690

goto mandos_end;

590

return -1;

691

591

}

692

592

/* Set the network interface number as scope */

693

593

to.in6.sin6_scope_id = (uint32_t)if_index;

698

598

-Wunreachable-code */

699

599

}

700

600

701

if(quit_now){

702

errno = EINTR;

703

goto mandos_end;

704

}

705

706

601

if(debug){

707

602

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

708

603

char interface[IF_NAMESIZE];

709

604

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

710

perror_plus("if_indextoname");

605

perror("if_indextoname");

711

606

} else {

712

607

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

713

608

ip, interface, port);

727

622

sizeof(addrstr));

728

623

}

729

624

if(pcret == NULL){

730

perror_plus("inet_ntop");

625

perror("inet_ntop");

731

626

} else {

732

627

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

733

628

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

735

630

}

736

631

}

737

632

738

if(quit_now){

739

errno = EINTR;

740

goto mandos_end;

741

}

742

743

633

if(af == AF_INET6){

744

634

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

745

635

} else {

746

636

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

747

637

}

748

638

if(ret < 0){

749

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

750

int e = errno;

751

perror_plus("connect");

752

errno = e;

753

}

754

goto mandos_end;

755

}

756

757

if(quit_now){

758

errno = EINTR;

759

goto mandos_end;

639

perror("connect");

640

return -1;

760

641

}

761

642

762

643

const char *out = mandos_protocol_version;

766

647

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

767

648

out_size - written));

768

649

if(ret == -1){

769

int e = errno;

770

perror_plus("write");

771

errno = e;

650

perror("write");

651

retval = -1;

772

652

goto mandos_end;

773

653

}

774

654

written += (size_t)ret;

782

662

break;

783

663

}

784

664

}

785

786

if(quit_now){

787

errno = EINTR;

788

goto mandos_end;

789

}

790

665

}

791

666

792

667

if(debug){

793

668

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

794

669

}

795

670

796

if(quit_now){

797

errno = EINTR;

798

goto mandos_end;

799

}

800

801

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

802

671

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

803

672

804

if(quit_now){

805

errno = EINTR;

806

goto mandos_end;

807

}

808

809

do {

673

do{

810

674

ret = gnutls_handshake(session);

811

if(quit_now){

812

errno = EINTR;

813

goto mandos_end;

814

}

815

675

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

816

676

817

677

if(ret != GNUTLS_E_SUCCESS){

819

679

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

820

680

gnutls_perror(ret);

821

681

}

822

errno = EPROTO;

682

retval = -1;

823

683

goto mandos_end;

824

684

}

825

685

831

691

}

832

692

833

693

while(true){

834

835

if(quit_now){

836

errno = EINTR;

837

goto mandos_end;

838

}

839

840

694

buffer_capacity = incbuffer(&buffer, buffer_length,

841

695

buffer_capacity);

842

696

if(buffer_capacity == 0){

843

int e = errno;

844

perror_plus("incbuffer");

845

errno = e;

846

goto mandos_end;

847

}

848

849

if(quit_now){

850

errno = EINTR;

697

perror("incbuffer");

698

retval = -1;

851

699

goto mandos_end;

852

700

}

853

701

862

710

case GNUTLS_E_AGAIN:

863

711

break;

864

712

case GNUTLS_E_REHANDSHAKE:

865

do {

713

do{

866

714

ret = gnutls_handshake(session);

867

868

if(quit_now){

869

errno = EINTR;

870

goto mandos_end;

871

}

872

715

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

873

716

if(ret < 0){

874

717

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

875

718

gnutls_perror(ret);

876

errno = EPROTO;

719

retval = -1;

877

720

goto mandos_end;

878

721

}

879

722

break;

880

723

default:

881

724

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

882

725

" encrypted session with Mandos server\n");

726

retval = -1;

883

727

gnutls_bye(session, GNUTLS_SHUT_RDWR);

884

errno = EIO;

885

728

goto mandos_end;

886

729

}

887

730

} else {

893

736

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

894

737

}

895

738

896

if(quit_now){

897

errno = EINTR;

898

goto mandos_end;

899

}

900

901

do {

902

ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);

903

if(quit_now){

904

errno = EINTR;

905

goto mandos_end;

906

}

907

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

739

gnutls_bye(session, GNUTLS_SHUT_RDWR);

908

740

909

741

if(buffer_length > 0){

910

ssize_t decrypted_buffer_size;

911

742

decrypted_buffer_size = pgp_packet_decrypt(buffer,

912

743

buffer_length,

913

744

&decrypted_buffer);

914

745

if(decrypted_buffer_size >= 0){

915

916

746

written = 0;

917

747

while(written < (size_t) decrypted_buffer_size){

918

if(quit_now){

919

errno = EINTR;

920

goto mandos_end;

921

}

922

923

748

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

924

749

(size_t)decrypted_buffer_size - written,

925

750

stdout);

926

751

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

927

int e = errno;

928

752

if(debug){

929

753

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

930

754

strerror(errno));

931

755

}

932

errno = e;

933

goto mandos_end;

756

retval = -1;

757

break;

934

758

}

935

759

written += (size_t)ret;

936

760

}

937

retval = 0;

761

free(decrypted_buffer);

762

} else {

763

retval = -1;

938

764

}

765

} else {

766

retval = -1;

939

767

}

940

768

941

769

/* Shutdown procedure */

942

770

943

771

mandos_end:

944

{

945

int e = errno;

946

free(decrypted_buffer);

947

free(buffer);

948

if(tcp_sd >= 0){

949

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

950

}

951

if(ret == -1){

952

if(e == 0){

953

e = errno;

954

}

955

perror_plus("close");

956

}

957

gnutls_deinit(session);

958

errno = e;

959

if(quit_now){

960

errno = EINTR;

961

retval = -1;

962

}

772

free(buffer);

773

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

774

if(ret == -1){

775

perror("close");

963

776

}

777

gnutls_deinit(session);

964

778

return retval;

965

779

}

966

780

983

797

/* Called whenever a service has been resolved successfully or

984

798

timed out */

985

799

986

if(quit_now){

987

return;

988

}

989

990

800

switch(event){

991

801

default:

992

802

case AVAHI_RESOLVER_FAILURE:

1008

818

avahi_proto_to_af(proto));

1009

819

if(ret == 0){

1010

820

avahi_simple_poll_quit(mc.simple_poll);

1011

} else {

1012

ret = add_server(ip, port, interface,

1013

avahi_proto_to_af(proto));

1014

821

}

1015

822

}

1016

823

}

1032

839

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

1033

840

is removed from the LAN */

1034

841

1035

if(quit_now){

1036

return;

1037

}

1038

1039

842

switch(event){

1040

843

default:

1041

844

case AVAHI_BROWSER_FAILURE:

1051

854

the callback function is called the Avahi server will free the

1052

855

resolver for us. */

1053

856

1054

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

1055

name, type, domain, protocol, 0,

1056

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)))

1057

861

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

1058

862

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

1059

863

break;

1070

874

}

1071

875

}

1072

876

1073

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

1074

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){

1075

881

if(quit_now){

1076

882

return;

1077

883

}

1078

884

quit_now = 1;

1079

signal_received = sig;

1080

885

int old_errno = errno;

1081

/* set main loop to exit */

1082

886

if(mc.simple_poll != NULL){

1083

887

avahi_simple_poll_quit(mc.simple_poll);

1084

888

}

1085

889

errno = old_errno;

1086

890

}

1087

891

1088

/*

1089

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

1090

* corresponds to an acceptable network device.

1091

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

1092

*/

1093

int good_interface(const struct dirent *if_entry){

1094

ssize_t ssret;

1095

char *flagname = NULL;

1096

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

1097

return 0;

1098

}

1099

int ret = asprintf(&flagname, "%s/%s/flags", sys_class_net,

1100

if_entry->d_name);

1101

if(ret < 0){

1102

perror_plus("asprintf");

1103

return 0;

1104

}

1105

int flags_fd = (int)TEMP_FAILURE_RETRY(open(flagname, O_RDONLY));

1106

if(flags_fd == -1){

1107

perror_plus("open");

1108

free(flagname);

1109

return 0;

1110

}

1111

free(flagname);

1112

typedef short ifreq_flags; /* ifreq.ifr_flags in netdevice(7) */

1113

/* read line from flags_fd */

1114

ssize_t to_read = 2+(sizeof(ifreq_flags)*2)+1; /* "0x1003\n" */

1115

char *flagstring = malloc((size_t)to_read+1); /* +1 for final \0 */

1116

flagstring[(size_t)to_read] = '\0';

1117

if(flagstring == NULL){

1118

perror_plus("malloc");

1119

close(flags_fd);

1120

return 0;

1121

}

1122

while(to_read > 0){

1123

ssret = (ssize_t)TEMP_FAILURE_RETRY(read(flags_fd, flagstring,

1124

(size_t)to_read));

1125

if(ssret == -1){

1126

perror_plus("read");

1127

free(flagstring);

1128

close(flags_fd);

1129

return 0;

1130

}

1131

to_read -= ssret;

1132

if(ssret == 0){

1133

break;

1134

}

1135

}

1136

close(flags_fd);

1137

intmax_t tmpmax;

1138

char *tmp;

1139

errno = 0;

1140

tmpmax = strtoimax(flagstring, &tmp, 0);

1141

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

1142

and not (isspace(*tmp)))

1143

or tmpmax != (ifreq_flags)tmpmax){

1144

if(debug){

1145

fprintf(stderr, "Invalid flags \"%s\" for interface \"%s\"\n",

1146

flagstring, if_entry->d_name);

1147

}

1148

free(flagstring);

1149

return 0;

1150

}

1151

free(flagstring);

1152

ifreq_flags flags = (ifreq_flags)tmpmax;

1153

/* Reject the loopback device */

1154

if(flags & IFF_LOOPBACK){

1155

if(debug){

1156

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

1157

if_entry->d_name);

1158

}

1159

return 0;

1160

}

1161

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

1162

if(connect_to != NULL and (flags & IFF_POINTOPOINT)){

1163

if(debug){

1164

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

1165

if_entry->d_name);

1166

}

1167

return 1;

1168

}

1169

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

1170

if(not (flags & IFF_BROADCAST)){

1171

if(debug){

1172

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

1173

if_entry->d_name);

1174

}

1175

return 0;

1176

}

1177

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

1178

if(flags & IFF_NOARP){

1179

if(debug){

1180

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

1181

if_entry->d_name);

1182

}

1183

return 0;

1184

}

1185

/* Accept this device */

1186

if(debug){

1187

fprintf(stderr, "Interface \"%s\" is acceptable\n",

1188

if_entry->d_name);

1189

}

1190

return 1;

1191

}

1192

1193

int notdotentries(const struct dirent *direntry){

1194

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

1195

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

1196

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

1197

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

1198

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

1199

return 0;

1200

}

1201

return 1;

1202

}

1203

1204

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1205

int ret;

1206

struct timespec now;

1207

struct timespec waited_time;

1208

intmax_t block_time;

1209

1210

while(true){

1211

if(mc.current_server == NULL){

1212

if (debug){

1213

fprintf(stderr,

1214

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

1215

}

1216

ret = avahi_simple_poll_iterate(s, -1);

1217

} else {

1218

if (debug){

1219

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

1220

" or wait\n");

1221

}

1222

/* the current time */

1223

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1224

if(ret == -1){

1225

perror_plus("clock_gettime");

1226

return -1;

1227

}

1228

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

1229

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

1230

waited_time.tv_sec = (now.tv_sec

1231

- mc.current_server->last_seen.tv_sec);

1232

waited_time.tv_nsec = (now.tv_nsec

1233

- mc.current_server->last_seen.tv_nsec);

1234

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

1235

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

1236

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

1237

block_time = ((retry_interval

1238

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

1239

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

1240

1241

if (debug){

1242

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

1243

}

1244

1245

if(block_time <= 0){

1246

ret = start_mandos_communication(mc.current_server->ip,

1247

mc.current_server->port,

1248

mc.current_server->if_index,

1249

mc.current_server->af);

1250

if(ret == 0){

1251

avahi_simple_poll_quit(mc.simple_poll);

1252

return 0;

1253

}

1254

ret = clock_gettime(CLOCK_MONOTONIC,

1255

&mc.current_server->last_seen);

1256

if(ret == -1){

1257

perror_plus("clock_gettime");

1258

return -1;

1259

}

1260

mc.current_server = mc.current_server->next;

1261

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

1262

servers, but don't block */

1263

}

1264

1265

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

1266

}

1267

if(ret != 0){

1268

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

1269

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

1270

}

1271

}

1272

}

1273

}

1274

1275

892

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

1276

893

AvahiSServiceBrowser *sb = NULL;

1277

894

int error;

1279

896

intmax_t tmpmax;

1280

897

char *tmp;

1281

898

int exitcode = EXIT_SUCCESS;

1282

const char *interface = "";

899

const char *interface = "eth0";

1283

900

struct ifreq network;

1284

int sd = -1;

1285

bool take_down_interface = false;

901

int sd;

1286

902

uid_t uid;

1287

903

gid_t gid;

904

char *connect_to = NULL;

1288

905

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

1289

906

bool tempdir_created = false;

1290

907

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1291

908

const char *seckey = PATHDIR "/" SECKEY;

1292

909

const char *pubkey = PATHDIR "/" PUBKEY;

1293

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" };

1294

915

bool gnutls_initialized = false;

1295

916

bool gpgme_initialized = false;

1296

917

float delay = 2.5f;

1297

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

1298

retrying the same server again */

1299

918

1300

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

919

struct sigaction old_sigterm_action;

1301

920

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

1302

921

1303

uid = getuid();

1304

gid = getgid();

1305

1306

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

1307

errno = 0;

1308

ret = setgid(gid);

1309

if(ret == -1){

1310

perror_plus("setgid");

1311

}

1312

1313

/* Lower user privileges (temporarily) */

1314

errno = 0;

1315

ret = seteuid(uid);

1316

if(ret == -1){

1317

perror_plus("seteuid");

1318

}

1319

1320

if(quit_now){

1321

goto end;

1322

}

1323

1324

922

{

1325

923

struct argp_option options[] = {

1326

924

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

1355

953

.arg = "SECONDS",

1356

954

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

1357

955

.group = 2 },

1358

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

1359

.arg = "SECONDS",

1360

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

1361

.group = 2 },

1362

/*

1363

* These reproduce what we would get without ARGP_NO_HELP

1364

*/

1365

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

1366

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

1367

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

1368

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

1369

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

1370

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

1371

956

{ .name = NULL }

1372

957

};

1373

958

1374

959

error_t parse_opt(int key, char *arg,

1375

960

struct argp_state *state){

1376

errno = 0;

1377

961

switch(key){

1378

962

case 128: /* --debug */

1379

963

debug = true;

1395

979

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

1396

980

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

1397

981

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

1398

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

982

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

983

exit(EXIT_FAILURE);

1399

984

}

1400

985

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

1401

986

break;

1406

991

errno = 0;

1407

992

delay = strtof(arg, &tmp);

1408

993

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

1409

argp_error(state, "Bad delay");

1410

}

1411

case 132: /* --retry */

1412

errno = 0;

1413

retry_interval = strtod(arg, &tmp);

1414

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

1415

or (retry_interval * 1000) > INT_MAX

1416

or retry_interval < 0){

1417

argp_error(state, "Bad retry interval");

994

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

995

exit(EXIT_FAILURE);

1418

996

}

1419

997

break;

1420

/*

1421

* These reproduce what we would get without ARGP_NO_HELP

1422

*/

1423

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

1424

argp_state_help(state, state->out_stream,

1425

(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)

1426

& ~(unsigned int)ARGP_HELP_EXIT_OK);

1427

case -3: /* --usage */

1428

argp_state_help(state, state->out_stream,

1429

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1430

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

1431

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

1432

exit(argp_err_exit_status);

998

case ARGP_KEY_ARG:

999

argp_usage(state);

1000

case ARGP_KEY_END:

1433

1001

break;

1434

1002

default:

1435

1003

return ARGP_ERR_UNKNOWN;

1436

1004

}

1437

return errno;

1005

return 0;

1438

1006

}

1439

1007

1440

1008

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

1441

1009

.args_doc = "",

1442

1010

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

1443

1011

" passwords from a Mandos server" };

1444

ret = argp_parse(&argp, argc, argv,

1445

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1446

switch(ret){

1447

case 0:

1448

break;

1449

case ENOMEM:

1450

default:

1451

errno = ret;

1452

perror_plus("argp_parse");

1453

exitcode = EX_OSERR;

1454

goto end;

1455

case EINVAL:

1456

exitcode = EX_USAGE;

1457

goto end;

1458

}

1459

}

1460

1461

{

1462

/* Work around Debian bug #633582:

1463

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

1464

struct stat st;

1465

1466

/* Re-raise priviliges */

1467

errno = 0;

1468

ret = seteuid(0);

1469

if(ret == -1){

1470

perror_plus("seteuid");

1471

}

1472

1473

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

1474

int seckey_fd = open(seckey, O_RDONLY);

1475

if(seckey_fd == -1){

1476

perror_plus("open");

1477

} else {

1478

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

1479

if(ret == -1){

1480

perror_plus("fstat");

1481

} else {

1482

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

1483

ret = fchown(seckey_fd, uid, gid);

1484

if(ret == -1){

1485

perror_plus("fchown");

1486

}

1487

}

1488

}

1489

TEMP_FAILURE_RETRY(close(seckey_fd));

1490

}

1491

}

1492

1493

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

1494

int pubkey_fd = open(pubkey, O_RDONLY);

1495

if(pubkey_fd == -1){

1496

perror_plus("open");

1497

} else {

1498

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

1499

if(ret == -1){

1500

perror_plus("fstat");

1501

} else {

1502

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

1503

ret = fchown(pubkey_fd, uid, gid);

1504

if(ret == -1){

1505

perror_plus("fchown");

1506

}

1507

}

1508

}

1509

TEMP_FAILURE_RETRY(close(pubkey_fd));

1510

}

1511

}

1512

1513

/* Lower privileges */

1514

errno = 0;

1515

ret = seteuid(uid);

1516

if(ret == -1){

1517

perror_plus("seteuid");

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;

1518

1017

}

1519

1018

}

1520

1019

1521

1020

if(not debug){

1522

1021

avahi_set_log_function(empty_log);

1523

1022

}

1524

1525

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

1526

struct dirent **direntries;

1527

ret = scandir(sys_class_net, &direntries, good_interface,

1528

alphasort);

1529

if(ret >= 1){

1530

/* Pick the first good interface */

1531

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

1532

if(debug){

1533

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

1534

}

1535

if(interface == NULL){

1536

perror_plus("malloc");

1537

free(direntries);

1538

exitcode = EXIT_FAILURE;

1539

goto end;

1540

}

1541

free(direntries);

1542

} else {

1543

free(direntries);

1544

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

1545

exitcode = EXIT_FAILURE;

1546

goto end;

1547

}

1548

}

1549

1023

1550

1024

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

1551

1025

from the signal handler */

1554

1028

mc.simple_poll = avahi_simple_poll_new();

1555

1029

if(mc.simple_poll == NULL){

1556

1030

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

1557

exitcode = EX_UNAVAILABLE;

1031

exitcode = EXIT_FAILURE;

1558

1032

goto end;

1559

1033

}

1560

1034

1561

1035

sigemptyset(&sigterm_action.sa_mask);

1562

1036

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

1563

1037

if(ret == -1){

1564

perror_plus("sigaddset");

1565

exitcode = EX_OSERR;

1038

perror("sigaddset");

1039

exitcode = EXIT_FAILURE;

1566

1040

goto end;

1567

1041

}

1568

1042

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

1569

1043

if(ret == -1){

1570

perror_plus("sigaddset");

1571

exitcode = EX_OSERR;

1044

perror("sigaddset");

1045

exitcode = EXIT_FAILURE;

1572

1046

goto end;

1573

1047

}

1574

1048

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

1575

1049

if(ret == -1){

1576

perror_plus("sigaddset");

1577

exitcode = EX_OSERR;

1578

goto end;

1579

}

1580

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

1581

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

1582

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

1583

*/

1584

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

1585

if(ret == -1){

1586

perror_plus("sigaction");

1587

return EX_OSERR;

1588

}

1589

if(old_sigterm_action.sa_handler != SIG_IGN){

1590

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

1591

if(ret == -1){

1592

perror_plus("sigaction");

1593

exitcode = EX_OSERR;

1594

goto end;

1595

}

1596

}

1597

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

1598

if(ret == -1){

1599

perror_plus("sigaction");

1600

return EX_OSERR;

1601

}

1602

if(old_sigterm_action.sa_handler != SIG_IGN){

1603

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

1604

if(ret == -1){

1605

perror_plus("sigaction");

1606

exitcode = EX_OSERR;

1607

goto end;

1608

}

1609

}

1610

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

1611

if(ret == -1){

1612

perror_plus("sigaction");

1613

return EX_OSERR;

1614

}

1615

if(old_sigterm_action.sa_handler != SIG_IGN){

1616

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

1617

if(ret == -1){

1618

perror_plus("sigaction");

1619

exitcode = EX_OSERR;

1620

goto end;

1621

}

1622

}

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

}

1623

1060

1624

1061

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

1625

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

1626

if_index = (AvahiIfIndex) if_nametoindex(interface);

1627

if(if_index == 0){

1628

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

1629

exitcode = EX_UNAVAILABLE;

1630

goto end;

1631

}

1632

1633

if(quit_now){

1634

goto end;

1635

}

1636

1637

/* Re-raise priviliges */

1638

errno = 0;

1639

ret = seteuid(0);

1640

if(ret == -1){

1641

perror_plus("seteuid");

1642

}

1643

1062

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

1644

1063

#ifdef __linux__

1645

1064

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1646

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

1065

messages to mess up the prompt */

1647

1066

ret = klogctl(8, NULL, 5);

1648

1067

bool restore_loglevel = true;

1649

1068

if(ret == -1){

1650

1069

restore_loglevel = false;

1651

perror_plus("klogctl");

1070

perror("klogctl");

1652

1071

}

1653

1072

#endif /* __linux__ */

1654

1073

1655

1074

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1656

1075

if(sd < 0){

1657

perror_plus("socket");

1658

exitcode = EX_OSERR;

1076

perror("socket");

1077

exitcode = EXIT_FAILURE;

1659

1078

#ifdef __linux__

1660

1079

if(restore_loglevel){

1661

1080

ret = klogctl(7, NULL, 0);

1662

1081

if(ret == -1){

1663

perror_plus("klogctl");

1082

perror("klogctl");

1664

1083

}

1665

1084

}

1666

1085

#endif /* __linux__ */

1667

/* Lower privileges */

1668

errno = 0;

1669

ret = seteuid(uid);

1670

if(ret == -1){

1671

perror_plus("seteuid");

1672

}

1673

1086

goto end;

1674

1087

}

1675

1088

strcpy(network.ifr_name, interface);

1676

1089

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

1677

1090

if(ret == -1){

1678

perror_plus("ioctl SIOCGIFFLAGS");

1091

perror("ioctl SIOCGIFFLAGS");

1679

1092

#ifdef __linux__

1680

1093

if(restore_loglevel){

1681

1094

ret = klogctl(7, NULL, 0);

1682

1095

if(ret == -1){

1683

perror_plus("klogctl");

1096

perror("klogctl");

1684

1097

}

1685

1098

}

1686

1099

#endif /* __linux__ */

1687

exitcode = EX_OSERR;

1688

/* Lower privileges */

1689

errno = 0;

1690

ret = seteuid(uid);

1691

if(ret == -1){

1692

perror_plus("seteuid");

1693

}

1100

exitcode = EXIT_FAILURE;

1694

1101

goto end;

1695

1102

}

1696

1103

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

1697

1104

network.ifr_flags |= IFF_UP;

1698

take_down_interface = true;

1699

1105

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

1700

1106

if(ret == -1){

1701

take_down_interface = false;

1702

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1703

exitcode = EX_OSERR;

1107

perror("ioctl SIOCSIFFLAGS");

1108

exitcode = EXIT_FAILURE;

1704

1109

#ifdef __linux__

1705

1110

if(restore_loglevel){

1706

1111

ret = klogctl(7, NULL, 0);

1707

1112

if(ret == -1){

1708

perror_plus("klogctl");

1113

perror("klogctl");

1709

1114

}

1710

1115

}

1711

1116

#endif /* __linux__ */

1712

/* Lower privileges */

1713

errno = 0;

1714

ret = seteuid(uid);

1715

if(ret == -1){

1716

perror_plus("seteuid");

1717

}

1718

1117

goto end;

1719

1118

}

1720

1119

}

1721

/* Sleep checking until interface is running.

1722

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

1120

/* sleep checking until interface is running */

1723

1121

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

1724

1122

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

1725

1123

if(ret == -1){

1726

perror_plus("ioctl SIOCGIFFLAGS");

1124

perror("ioctl SIOCGIFFLAGS");

1727

1125

} else if(network.ifr_flags & IFF_RUNNING){

1728

1126

break;

1729

1127

}

1730

1128

struct timespec sleeptime = { .tv_nsec = 250000000 };

1731

1129

ret = nanosleep(&sleeptime, NULL);

1732

1130

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

1733

perror_plus("nanosleep");

1131

perror("nanosleep");

1734

1132

}

1735

1133

}

1736

if(not take_down_interface){

1737

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

1738

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

1739

if(ret == -1){

1740

perror_plus("close");

1741

}

1134

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

1135

if(ret == -1){

1136

perror("close");

1742

1137

}

1743

1138

#ifdef __linux__

1744

1139

if(restore_loglevel){

1745

1140

/* Restores kernel loglevel to default */

1746

1141

ret = klogctl(7, NULL, 0);

1747

1142

if(ret == -1){

1748

perror_plus("klogctl");

1143

perror("klogctl");

1749

1144

}

1750

1145

}

1751

1146

#endif /* __linux__ */

1752

/* Lower privileges */

1753

errno = 0;

1754

if(take_down_interface){

1755

/* Lower privileges */

1756

ret = seteuid(uid);

1757

if(ret == -1){

1758

perror_plus("seteuid");

1759

}

1760

} else {

1761

/* Lower privileges permanently */

1762

ret = setuid(uid);

1763

if(ret == -1){

1764

perror_plus("setuid");

1765

}

1766

}

1767

}

1768

1769

if(quit_now){

1770

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");

1771

1161

}

1772

1162

1773

1163

ret = init_gnutls_global(pubkey, seckey);

1774

1164

if(ret == -1){

1775

1165

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

1776

exitcode = EX_UNAVAILABLE;

1166

exitcode = EXIT_FAILURE;

1777

1167

goto end;

1778

1168

} else {

1779

1169

gnutls_initialized = true;

1780

1170

}

1781

1171

1782

if(quit_now){

1783

goto end;

1784

}

1785

1786

1172

if(mkdtemp(tempdir) == NULL){

1787

perror_plus("mkdtemp");

1173

perror("mkdtemp");

1788

1174

goto end;

1789

1175

}

1790

1176

tempdir_created = true;

1791

1177

1792

if(quit_now){

1793

goto end;

1794

}

1795

1796

1178

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

1797

1179

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

1798

exitcode = EX_UNAVAILABLE;

1180

exitcode = EXIT_FAILURE;

1799

1181

goto end;

1800

1182

} else {

1801

1183

gpgme_initialized = true;

1802

1184

}

1803

1185

1804

if(quit_now){

1805

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

}

1806

1193

}

1807

1194

1808

1195

if(connect_to != NULL){

1811

1198

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

1812

1199

if(address == NULL){

1813

1200

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

1814

exitcode = EX_USAGE;

1815

goto end;

1816

}

1817

1818

if(quit_now){

1819

goto end;

1820

}

1821

1201

exitcode = EXIT_FAILURE;

1202

goto end;

1203

}

1822

1204

uint16_t port;

1823

1205

errno = 0;

1824

1206

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

1825

1207

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

1826

1208

or tmpmax != (uint16_t)tmpmax){

1827

1209

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

1828

exitcode = EX_USAGE;

1829

goto end;

1830

}

1831

1832

if(quit_now){

1833

goto end;

1834

}

1835

1210

exitcode = EXIT_FAILURE;

1211

goto end;

1212

}

1836

1213

port = (uint16_t)tmpmax;

1837

1214

*address = '\0';

1215

address = connect_to;

1838

1216

/* Colon in address indicates IPv6 */

1839

1217

int af;

1840

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

1218

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

1841

1219

af = AF_INET6;

1842

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

1843

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

1844

{

1845

connect_to++;

1846

address[-1] = '\0';

1847

}

1848

1220

} else {

1849

1221

af = AF_INET;

1850

1222

}

1851

address = connect_to;

1852

1853

if(quit_now){

1854

goto end;

1855

}

1856

1857

while(not quit_now){

1858

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

1859

if(quit_now or ret == 0){

1860

break;

1861

}

1862

if(debug){

1863

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

1864

(int)retry_interval);

1865

}

1866

sleep((int)retry_interval);

1867

}

1868

1869

if (not quit_now){

1223

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

1224

if(ret < 0){

1225

exitcode = EXIT_FAILURE;

1226

} else {

1870

1227

exitcode = EXIT_SUCCESS;

1871

1228

}

1872

1873

goto end;

1874

}

1875

1876

if(quit_now){

1877

goto end;

1878

}

1879

1229

goto end;

1230

}

1231

1880

1232

{

1881

1233

AvahiServerConfig config;

1882

1234

/* Do not publish any local Zeroconf records */

1899

1251

if(mc.server == NULL){

1900

1252

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

1901

1253

avahi_strerror(error));

1902

exitcode = EX_UNAVAILABLE;

1903

goto end;

1904

}

1905

1906

if(quit_now){

1254

exitcode = EXIT_FAILURE;

1907

1255

goto end;

1908

1256

}

1909

1257

1910

1258

/* Create the Avahi service browser */

1911

1259

sb = avahi_s_service_browser_new(mc.server, if_index,

1912

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

1260

AVAHI_PROTO_INET6, "_mandos._tcp",

1913

1261

NULL, 0, browse_callback, NULL);

1914

1262

if(sb == NULL){

1915

1263

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

1916

1264

avahi_strerror(avahi_server_errno(mc.server)));

1917

exitcode = EX_UNAVAILABLE;

1918

goto end;

1919

}

1920

1921

if(quit_now){

1265

exitcode = EXIT_FAILURE;

1922

1266

goto end;

1923

1267

}

1924

1268

1927

1271

if(debug){

1928

1272

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

1929

1273

}

1930

1931

ret = avahi_loop_with_timeout(mc.simple_poll,

1932

(int)(retry_interval * 1000));

1933

if(debug){

1934

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

1935

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

1936

}

1274

1275

avahi_simple_poll_loop(mc.simple_poll);

1937

1276

1938

1277

end:

1939

1278

1960

1299

if(gpgme_initialized){

1961

1300

gpgme_release(mc.ctx);

1962

1301

}

1963

1964

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

1965

has seen */

1966

if(mc.current_server != NULL){

1967

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

1968

while(mc.current_server != NULL){

1969

server *next = mc.current_server->next;

1970

free(mc.current_server);

1971

mc.current_server = next;

1972

}

1973

}

1974

1975

/* Take down the network interface */

1976

if(take_down_interface){

1977

/* Re-raise priviliges */

1978

errno = 0;

1979

ret = seteuid(0);

1980

if(ret == -1){

1981

perror_plus("seteuid");

1982

}

1983

if(geteuid() == 0){

1984

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

1985

if(ret == -1){

1986

perror_plus("ioctl SIOCGIFFLAGS");

1987

} else if(network.ifr_flags & IFF_UP) {

1988

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

1989

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

1990

if(ret == -1){

1991

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1992

}

1993

}

1994

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

1995

if(ret == -1){

1996

perror_plus("close");

1997

}

1998

/* Lower privileges permanently */

1999

errno = 0;

2000

ret = setuid(uid);

2001

if(ret == -1){

2002

perror_plus("setuid");

2003

}

2004

}

2005

}

2006

2007

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

1302

1303

/* Removes the temp directory used by GPGME */

2008

1304

if(tempdir_created){

2009

struct dirent **direntries = NULL;

2010

struct dirent *direntry = NULL;

2011

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

2012

alphasort);

2013

if (numentries > 0){

2014

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

2015

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

}

2016

1325

char *fullname = NULL;

2017

1326

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

2018

1327

direntry->d_name);

2019

1328

if(ret < 0){

2020

perror_plus("asprintf");

1329

perror("asprintf");

2021

1330

continue;

2022

1331

}

2023

1332

ret = remove(fullname);

2027

1336

}

2028

1337

free(fullname);

2029

1338

}

2030

}

2031

2032

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

2033

free(direntries);

2034

if (numentries == -1){

2035

perror_plus("scandir");

1339

closedir(d);

2036

1340

}

2037

1341

ret = rmdir(tempdir);

2038

1342

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

2039

perror_plus("rmdir");

2040

}

2041

}

2042

2043

if(quit_now){

2044

sigemptyset(&old_sigterm_action.sa_mask);

2045

old_sigterm_action.sa_handler = SIG_DFL;

2046

ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,

2047

&old_sigterm_action,

2048

NULL));

2049

if(ret == -1){

2050

perror_plus("sigaction");

2051

}

2052

do {

2053

ret = raise(signal_received);

2054

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

2055

if(ret != 0){

2056

perror_plus("raise");

2057

abort();

2058

}

2059

TEMP_FAILURE_RETRY(pause());

1343

perror("rmdir");

1344

}

2060

1345

}

2061

1346

2062

1347

return exitcode;