/mandos/release : revision 237.7.42

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

30

*/

31

32

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

33

#ifndef _LARGEFILE_SOURCE

33

34

#define _LARGEFILE_SOURCE

35

#endif

36

#ifndef _FILE_OFFSET_BITS

34

37

#define _FILE_OFFSET_BITS 64

38

#endif

35

39

36

40

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

37

41

38

42

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

39

stdout, ferror(), sscanf(),

40

remove() */

43

stdout, ferror(), remove() */

41

44

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

42

45

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

43

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

44

srand() */

46

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

47

strtof(), abort() */

45

48

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

46

49

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

47

50

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

56

59

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

57

60

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

58

61

*/

59

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

62

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

63

strtoimax() */

60

64

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

61

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

62

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

65

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

66

program_invocation_short_name */

67

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

63

68

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

64

69

SIOCSIFFLAGS, if_indextoname(),

65

70

if_nametoindex(), IF_NAMESIZE */

67

72

INET_ADDRSTRLEN, INET6_ADDRSTRLEN

68

73

*/

69

74

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

70

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

71

setgid() */

72

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

75

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

76

setgid(), pause() */

77

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

73

78

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

74

79

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

75

80

argp_state, struct argp,

76

81

argp_parse(), ARGP_KEY_ARG,

77

82

ARGP_KEY_END, ARGP_ERR_UNKNOWN */

78

83

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

79

sigaction(), SIGTERM, sigaction,

80

sig_atomic_t */

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 */

81

88

82

89

#ifdef __linux__

83

90

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

121

128

static const char mandos_protocol_version[] = "1";

122

129

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

123

130

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

124

144

125

145

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

126

146

typedef struct {

131

151

gnutls_dh_params_t dh_params;

132

152

const char *priority;

133

153

gpgme_ctx_t ctx;

154

server *current_server;

134

155

} mandos_context;

135

156

136

157

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

137

158

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

138

159

.dh_bits = 1024, .priority = "SECURE256"

139

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

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

}

140

172

141

173

/*

142

174

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

155

187

return buffer_capacity;

156

188

}

157

189

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

158

228

/*

159

229

* Initialize GPGME.

160

230

*/

161

231

static bool init_gpgme(const char *seckey,

162

232

const char *pubkey, const char *tempdir){

163

int ret;

164

233

gpgme_error_t rc;

165

234

gpgme_engine_info_t engine_info;

166

235

169

238

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

170

239

*/

171

240

bool import_key(const char *filename){

241

int ret;

172

242

int fd;

173

243

gpgme_data_t pgp_data;

174

244

175

245

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

176

246

if(fd == -1){

177

perror("open");

247

perror_plus("open");

178

248

return false;

179

249

}

180

250

194

264

195

265

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

196

266

if(ret == -1){

197

perror("close");

267

perror_plus("close");

198

268

}

199

269

gpgme_data_release(pgp_data);

200

270

return true;

213

283

return false;

214

284

}

215

285

216

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

286

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

217

287

rc = gpgme_get_engine_info(&engine_info);

218

288

if(rc != GPG_ERR_NO_ERROR){

219

289

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

245

315

return false;

246

316

}

247

317

248

return true;

318

return true;

249

319

}

250

320

251

321

/*

305

375

}

306

376

gpgme_recipient_t recipient;

307

377

recipient = result->recipients;

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

}

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;

318

386

}

319

387

}

320

388

}

327

395

328

396

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

329

397

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

330

perror("gpgme_data_seek");

398

perror_plus("gpgme_data_seek");

331

399

plaintext_length = -1;

332

400

goto decrypt_end;

333

401

}

338

406

(size_t)plaintext_length,

339

407

plaintext_capacity);

340

408

if(plaintext_capacity == 0){

341

perror("incbuffer");

409

perror_plus("incbuffer");

342

410

plaintext_length = -1;

343

411

goto decrypt_end;

344

412

}

351

419

break;

352

420

}

353

421

if(ret < 0){

354

perror("gpgme_data_read");

422

perror_plus("gpgme_data_read");

355

423

plaintext_length = -1;

356

424

goto decrypt_end;

357

425

}

414

482

}

415

483

416

484

/* OpenPGP credentials */

417

gnutls_certificate_allocate_credentials(&mc.cred);

485

ret = gnutls_certificate_allocate_credentials(&mc.cred);

418

486

if(ret != GNUTLS_E_SUCCESS){

419

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

420

from

421

-Wunreachable-code

422

*/

487

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

423

488

safer_gnutls_strerror(ret));

424

489

gnutls_global_deinit();

425

490

return -1;

472

537

static int init_gnutls_session(gnutls_session_t *session){

473

538

int ret;

474

539

/* GnuTLS session creation */

475

ret = gnutls_init(session, GNUTLS_SERVER);

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);

476

546

if(ret != GNUTLS_E_SUCCESS){

477

547

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

478

548

safer_gnutls_strerror(ret));

480

550

481

551

{

482

552

const char *err;

483

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

484

560

if(ret != GNUTLS_E_SUCCESS){

485

561

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

486

562

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

490

566

}

491

567

}

492

568

493

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

494

mc.cred);

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);

495

577

if(ret != GNUTLS_E_SUCCESS){

496

578

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

497

579

safer_gnutls_strerror(ret));

500

582

}

501

583

502

584

/* ignore client certificate if any. */

503

gnutls_certificate_server_set_request(*session,

504

GNUTLS_CERT_IGNORE);

585

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

505

586

506

587

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

507

588

516

597

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

517

598

AvahiIfIndex if_index,

518

599

int af){

519

int ret, tcp_sd;

600

int ret, tcp_sd = -1;

520

601

ssize_t sret;

521

602

union {

522

603

struct sockaddr_in in;

523

604

struct sockaddr_in6 in6;

524

605

} to;

525

606

char *buffer = NULL;

526

char *decrypted_buffer;

607

char *decrypted_buffer = NULL;

527

608

size_t buffer_length = 0;

528

609

size_t buffer_capacity = 0;

529

ssize_t decrypted_buffer_size;

530

610

size_t written;

531

int retval = 0;

611

int retval = -1;

532

612

gnutls_session_t session;

533

613

int pf; /* Protocol family */

534

614

615

errno = 0;

616

617

if(quit_now){

618

errno = EINTR;

619

return -1;

620

}

621

535

622

switch(af){

536

623

case AF_INET6:

537

624

pf = PF_INET6;

541

628

break;

542

629

default:

543

630

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

631

errno = EINVAL;

544

632

return -1;

545

633

}

546

634

556

644

557

645

tcp_sd = socket(pf, SOCK_STREAM, 0);

558

646

if(tcp_sd < 0){

559

perror("socket");

560

return -1;

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;

561

656

}

562

657

563

658

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

564

659

if(af == AF_INET6){

565

to.in6.sin6_family = (uint16_t)af;

660

to.in6.sin6_family = (sa_family_t)af;

566

661

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

567

662

} else { /* IPv4 */

568

663

to.in.sin_family = (sa_family_t)af;

569

664

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

570

665

}

571

666

if(ret < 0 ){

572

perror("inet_pton");

573

return -1;

667

int e = errno;

668

perror_plus("inet_pton");

669

errno = e;

670

goto mandos_end;

574

671

}

575

672

if(ret == 0){

673

int e = errno;

576

674

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

577

return -1;

675

errno = e;

676

goto mandos_end;

578

677

}

579

678

if(af == AF_INET6){

580

679

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

587

686

if(if_index == AVAHI_IF_UNSPEC){

588

687

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

589

688

" without a network interface\n");

590

return -1;

689

errno = EINVAL;

690

goto mandos_end;

591

691

}

592

692

/* Set the network interface number as scope */

593

693

to.in6.sin6_scope_id = (uint32_t)if_index;

598

698

-Wunreachable-code */

599

699

}

600

700

701

if(quit_now){

702

errno = EINTR;

703

goto mandos_end;

704

}

705

601

706

if(debug){

602

707

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

603

708

char interface[IF_NAMESIZE];

604

709

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

605

perror("if_indextoname");

710

perror_plus("if_indextoname");

606

711

} else {

607

712

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

608

713

ip, interface, port);

622

727

sizeof(addrstr));

623

728

}

624

729

if(pcret == NULL){

625

perror("inet_ntop");

730

perror_plus("inet_ntop");

626

731

} else {

627

732

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

628

733

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

630

735

}

631

736

}

632

737

738

if(quit_now){

739

errno = EINTR;

740

goto mandos_end;

741

}

742

633

743

if(af == AF_INET6){

634

744

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

635

745

} else {

636

746

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

637

747

}

638

748

if(ret < 0){

639

perror("connect");

640

return -1;

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;

641

760

}

642

761

643

762

const char *out = mandos_protocol_version;

647

766

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

648

767

out_size - written));

649

768

if(ret == -1){

650

perror("write");

651

retval = -1;

769

int e = errno;

770

perror_plus("write");

771

errno = e;

652

772

goto mandos_end;

653

773

}

654

774

written += (size_t)ret;

662

782

break;

663

783

}

664

784

}

785

786

if(quit_now){

787

errno = EINTR;

788

goto mandos_end;

789

}

665

790

}

666

791

667

792

if(debug){

668

793

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

669

794

}

670

795

796

if(quit_now){

797

errno = EINTR;

798

goto mandos_end;

799

}

800

801

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

671

802

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

672

803

673

do{

804

if(quit_now){

805

errno = EINTR;

806

goto mandos_end;

807

}

808

809

do {

674

810

ret = gnutls_handshake(session);

811

if(quit_now){

812

errno = EINTR;

813

goto mandos_end;

814

}

675

815

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

676

816

677

817

if(ret != GNUTLS_E_SUCCESS){

679

819

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

680

820

gnutls_perror(ret);

681

821

}

682

retval = -1;

822

errno = EPROTO;

683

823

goto mandos_end;

684

824

}

685

825

691

831

}

692

832

693

833

while(true){

834

835

if(quit_now){

836

errno = EINTR;

837

goto mandos_end;

838

}

839

694

840

buffer_capacity = incbuffer(&buffer, buffer_length,

695

841

buffer_capacity);

696

842

if(buffer_capacity == 0){

697

perror("incbuffer");

698

retval = -1;

843

int e = errno;

844

perror_plus("incbuffer");

845

errno = e;

846

goto mandos_end;

847

}

848

849

if(quit_now){

850

errno = EINTR;

699

851

goto mandos_end;

700

852

}

701

853

710

862

case GNUTLS_E_AGAIN:

711

863

break;

712

864

case GNUTLS_E_REHANDSHAKE:

713

do{

865

do {

714

866

ret = gnutls_handshake(session);

867

868

if(quit_now){

869

errno = EINTR;

870

goto mandos_end;

871

}

715

872

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

716

873

if(ret < 0){

717

874

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

718

875

gnutls_perror(ret);

719

retval = -1;

876

errno = EPROTO;

720

877

goto mandos_end;

721

878

}

722

879

break;

723

880

default:

724

881

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

725

882

" encrypted session with Mandos server\n");

726

retval = -1;

727

883

gnutls_bye(session, GNUTLS_SHUT_RDWR);

884

errno = EIO;

728

885

goto mandos_end;

729

886

}

730

887

} else {

736

893

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

737

894

}

738

895

739

gnutls_bye(session, GNUTLS_SHUT_RDWR);

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);

740

908

741

909

if(buffer_length > 0){

910

ssize_t decrypted_buffer_size;

742

911

decrypted_buffer_size = pgp_packet_decrypt(buffer,

743

912

buffer_length,

744

913

&decrypted_buffer);

745

914

if(decrypted_buffer_size >= 0){

915

746

916

written = 0;

747

917

while(written < (size_t) decrypted_buffer_size){

918

if(quit_now){

919

errno = EINTR;

920

goto mandos_end;

921

}

922

748

923

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

749

924

(size_t)decrypted_buffer_size - written,

750

925

stdout);

751

926

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

927

int e = errno;

752

928

if(debug){

753

929

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

754

930

strerror(errno));

755

931

}

756

retval = -1;

757

break;

932

errno = e;

933

goto mandos_end;

758

934

}

759

935

written += (size_t)ret;

760

936

}

761

free(decrypted_buffer);

762

} else {

763

retval = -1;

937

retval = 0;

764

938

}

765

} else {

766

retval = -1;

767

939

}

768

940

769

941

/* Shutdown procedure */

770

942

771

943

mandos_end:

772

free(buffer);

773

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

774

if(ret == -1){

775

perror("close");

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

}

776

963

}

777

gnutls_deinit(session);

778

964

return retval;

779

965

}

780

966

797

983

/* Called whenever a service has been resolved successfully or

798

984

timed out */

799

985

986

if(quit_now){

987

return;

988

}

989

800

990

switch(event){

801

991

default:

802

992

case AVAHI_RESOLVER_FAILURE:

818

1008

avahi_proto_to_af(proto));

819

1009

if(ret == 0){

820

1010

avahi_simple_poll_quit(mc.simple_poll);

1011

} else {

1012

ret = add_server(ip, port, interface,

1013

avahi_proto_to_af(proto));

821

1014

}

822

1015

}

823

1016

}

839

1032

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

840

1033

is removed from the LAN */

841

1034

1035

if(quit_now){

1036

return;

1037

}

1038

842

1039

switch(event){

843

1040

default:

844

1041

case AVAHI_BROWSER_FAILURE:

854

1051

the callback function is called the Avahi server will free the

855

1052

resolver for us. */

856

1053

857

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

858

protocol, name, type, domain,

859

AVAHI_PROTO_INET6, 0,

860

resolve_callback, NULL)))

1054

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

1055

name, type, domain, protocol, 0,

1056

resolve_callback, NULL) == NULL)

861

1057

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

862

1058

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

863

1059

break;

874

1070

}

875

1071

}

876

1072

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){

1073

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

1074

static void handle_sigterm(int sig){

881

1075

if(quit_now){

882

1076

return;

883

1077

}

884

1078

quit_now = 1;

1079

signal_received = sig;

885

1080

int old_errno = errno;

1081

/* set main loop to exit */

886

1082

if(mc.simple_poll != NULL){

887

1083

avahi_simple_poll_quit(mc.simple_poll);

888

1084

}

889

1085

errno = old_errno;

890

1086

}

891

1087

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

892

1275

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

893

1276

AvahiSServiceBrowser *sb = NULL;

894

1277

int error;

895

1278

int ret;

896

1279

intmax_t tmpmax;

897

int numchars;

1280

char *tmp;

898

1281

int exitcode = EXIT_SUCCESS;

899

const char *interface = "eth0";

1282

const char *interface = "";

900

1283

struct ifreq network;

901

int sd;

1284

int sd = -1;

1285

bool take_down_interface = false;

902

1286

uid_t uid;

903

1287

gid_t gid;

904

char *connect_to = NULL;

905

1288

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

906

1289

bool tempdir_created = false;

907

1290

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

908

1291

const char *seckey = PATHDIR "/" SECKEY;

909

1292

const char *pubkey = PATHDIR "/" PUBKEY;

910

1293

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" };

915

1294

bool gnutls_initialized = false;

916

1295

bool gpgme_initialized = false;

917

double delay = 2.5;

918

919

struct sigaction old_sigterm_action;

1296

float delay = 2.5f;

1297

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

1298

retrying the same server again */

1299

1300

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

920

1301

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

921

1302

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

922

1324

{

923

1325

struct argp_option options[] = {

924

1326

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

953

1355

.arg = "SECONDS",

954

1356

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

955

1357

.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 },

956

1371

{ .name = NULL }

957

1372

};

958

1373

959

1374

error_t parse_opt(int key, char *arg,

960

1375

struct argp_state *state){

1376

errno = 0;

961

1377

switch(key){

962

1378

case 128: /* --debug */

963

1379

debug = true;

975

1391

pubkey = arg;

976

1392

break;

977

1393

case 129: /* --dh-bits */

978

ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);

979

if(ret < 1 or tmpmax != (typeof(mc.dh_bits))tmpmax

980

or arg[numchars] != '\0'){

981

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

982

exit(EXIT_FAILURE);

1394

errno = 0;

1395

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

1396

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

1397

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

1398

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

983

1399

}

984

1400

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

985

1401

break;

987

1403

mc.priority = arg;

988

1404

break;

989

1405

case 131: /* --delay */

990

ret = sscanf(arg, "%lf%n", &delay, &numchars);

991

if(ret < 1 or arg[numchars] != '\0'){

992

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

993

exit(EXIT_FAILURE);

1406

errno = 0;

1407

delay = strtof(arg, &tmp);

1408

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

1418

}

995

1419

break;

996

case ARGP_KEY_ARG:

997

argp_usage(state);

998

case ARGP_KEY_END:

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);

999

1433

break;

1000

1434

default:

1001

1435

return ARGP_ERR_UNKNOWN;

1002

1436

}

1003

return 0;

1437

return errno;

1004

1438

}

1005

1439

1006

1440

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

1007

1441

.args_doc = "",

1008

1442

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

1009

1443

" passwords from a Mandos server" };

1010

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

1011

if(ret == ARGP_ERR_UNKNOWN){

1012

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

1013

exitcode = EXIT_FAILURE;

1014

goto end;

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");

1015

1518

}

1016

1519

}

1017

1520

1018

1521

if(not debug){

1019

1522

avahi_set_log_function(empty_log);

1020

1523

}

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

}

1021

1549

1022

1550

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

1023

1551

from the signal handler */

1026

1554

mc.simple_poll = avahi_simple_poll_new();

1027

1555

if(mc.simple_poll == NULL){

1028

1556

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

1029

exitcode = EXIT_FAILURE;

1557

exitcode = EX_UNAVAILABLE;

1030

1558

goto end;

1031

1559

}

1032

1560

1033

1561

sigemptyset(&sigterm_action.sa_mask);

1034

1562

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

1035

1563

if(ret == -1){

1036

perror("sigaddset");

1037

exitcode = EXIT_FAILURE;

1564

perror_plus("sigaddset");

1565

exitcode = EX_OSERR;

1038

1566

goto end;

1039

1567

}

1040

1568

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

1041

1569

if(ret == -1){

1042

perror("sigaddset");

1043

exitcode = EXIT_FAILURE;

1570

perror_plus("sigaddset");

1571

exitcode = EX_OSERR;

1044

1572

goto end;

1045

1573

}

1046

1574

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

1047

1575

if(ret == -1){

1048

perror("sigaddset");

1049

exitcode = EXIT_FAILURE;

1050

goto end;

1051

}

1052

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

1053

if(ret == -1){

1054

perror("sigaction");

1055

exitcode = EXIT_FAILURE;

1056

goto end;

1057

}

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

}

1058

1623

1059

1624

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

1060

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

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

1061

1644

#ifdef __linux__

1062

1645

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1063

messages to mess up the prompt */

1646

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

1064

1647

ret = klogctl(8, NULL, 5);

1065

1648

bool restore_loglevel = true;

1066

1649

if(ret == -1){

1067

1650

restore_loglevel = false;

1068

perror("klogctl");

1651

perror_plus("klogctl");

1069

1652

}

1070

1653

#endif /* __linux__ */

1071

1654

1072

1655

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1073

1656

if(sd < 0){

1074

perror("socket");

1075

exitcode = EXIT_FAILURE;

1657

perror_plus("socket");

1658

exitcode = EX_OSERR;

1076

1659

#ifdef __linux__

1077

1660

if(restore_loglevel){

1078

1661

ret = klogctl(7, NULL, 0);

1079

1662

if(ret == -1){

1080

perror("klogctl");

1663

perror_plus("klogctl");

1081

1664

}

1082

1665

}

1083

1666

#endif /* __linux__ */

1667

/* Lower privileges */

1668

errno = 0;

1669

ret = seteuid(uid);

1670

if(ret == -1){

1671

perror_plus("seteuid");

1672

}

1084

1673

goto end;

1085

1674

}

1086

1675

strcpy(network.ifr_name, interface);

1087

1676

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

1088

1677

if(ret == -1){

1089

perror("ioctl SIOCGIFFLAGS");

1678

perror_plus("ioctl SIOCGIFFLAGS");

1090

1679

#ifdef __linux__

1091

1680

if(restore_loglevel){

1092

1681

ret = klogctl(7, NULL, 0);

1093

1682

if(ret == -1){

1094

perror("klogctl");

1683

perror_plus("klogctl");

1095

1684

}

1096

1685

}

1097

1686

#endif /* __linux__ */

1098

exitcode = EXIT_FAILURE;

1687

exitcode = EX_OSERR;

1688

/* Lower privileges */

1689

errno = 0;

1690

ret = seteuid(uid);

1691

if(ret == -1){

1692

perror_plus("seteuid");

1693

}

1099

1694

goto end;

1100

1695

}

1101

1696

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

1102

1697

network.ifr_flags |= IFF_UP;

1698

take_down_interface = true;

1103

1699

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

1104

1700

if(ret == -1){

1105

perror("ioctl SIOCSIFFLAGS");

1106

exitcode = EXIT_FAILURE;

1701

take_down_interface = false;

1702

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1703

exitcode = EX_OSERR;

1107

1704

#ifdef __linux__

1108

1705

if(restore_loglevel){

1109

1706

ret = klogctl(7, NULL, 0);

1110

1707

if(ret == -1){

1111

perror("klogctl");

1708

perror_plus("klogctl");

1112

1709

}

1113

1710

}

1114

1711

#endif /* __linux__ */

1712

/* Lower privileges */

1713

errno = 0;

1714

ret = seteuid(uid);

1715

if(ret == -1){

1716

perror_plus("seteuid");

1717

}

1115

1718

goto end;

1116

1719

}

1117

1720

}

1118

/* sleep checking until interface is running */

1721

/* Sleep checking until interface is running.

1722

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

1119

1723

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

1120

1724

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

1121

1725

if(ret == -1){

1122

perror("ioctl SIOCGIFFLAGS");

1726

perror_plus("ioctl SIOCGIFFLAGS");

1123

1727

} else if(network.ifr_flags & IFF_RUNNING){

1124

1728

break;

1125

1729

}

1126

1730

struct timespec sleeptime = { .tv_nsec = 250000000 };

1127

1731

ret = nanosleep(&sleeptime, NULL);

1128

1732

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

1129

perror("nanosleep");

1733

perror_plus("nanosleep");

1130

1734

}

1131

1735

}

1132

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

1133

if(ret == -1){

1134

perror("close");

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

}

1135

1742

}

1136

1743

#ifdef __linux__

1137

1744

if(restore_loglevel){

1138

1745

/* Restores kernel loglevel to default */

1139

1746

ret = klogctl(7, NULL, 0);

1140

1747

if(ret == -1){

1141

perror("klogctl");

1748

perror_plus("klogctl");

1142

1749

}

1143

1750

}

1144

1751

#endif /* __linux__ */

1145

}

1146

1147

uid = getuid();

1148

gid = getgid();

1149

1150

errno = 0;

1151

setgid(gid);

1152

if(ret == -1){

1153

perror("setgid");

1154

}

1155

1156

ret = setuid(uid);

1157

if(ret == -1){

1158

perror("setuid");

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;

1159

1771

}

1160

1772

1161

1773

ret = init_gnutls_global(pubkey, seckey);

1162

1774

if(ret == -1){

1163

1775

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

1164

exitcode = EXIT_FAILURE;

1776

exitcode = EX_UNAVAILABLE;

1165

1777

goto end;

1166

1778

} else {

1167

1779

gnutls_initialized = true;

1168

1780

}

1169

1781

1782

if(quit_now){

1783

goto end;

1784

}

1785

1170

1786

if(mkdtemp(tempdir) == NULL){

1171

perror("mkdtemp");

1787

perror_plus("mkdtemp");

1172

1788

goto end;

1173

1789

}

1174

1790

tempdir_created = true;

1175

1791

1792

if(quit_now){

1793

goto end;

1794

}

1795

1176

1796

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

1177

1797

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

1178

exitcode = EXIT_FAILURE;

1798

exitcode = EX_UNAVAILABLE;

1179

1799

goto end;

1180

1800

} else {

1181

1801

gpgme_initialized = true;

1182

1802

}

1183

1803

1184

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

1185

if_index = (AvahiIfIndex) if_nametoindex(interface);

1186

if(if_index == 0){

1187

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

1188

exitcode = EXIT_FAILURE;

1189

goto end;

1190

}

1804

if(quit_now){

1805

goto end;

1191

1806

}

1192

1807

1193

1808

if(connect_to != NULL){

1196

1811

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

1197

1812

if(address == NULL){

1198

1813

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

1199

exitcode = EXIT_FAILURE;

1200

goto end;

1201

}

1814

exitcode = EX_USAGE;

1815

goto end;

1816

}

1817

1818

if(quit_now){

1819

goto end;

1820

}

1821

1202

1822

uint16_t port;

1203

ret = sscanf(address+1, "%" SCNdMAX "%n", &tmpmax, &numchars);

1204

if(ret < 1 or tmpmax != (uint16_t)tmpmax

1205

or address[numchars+1] != '\0'){

1823

errno = 0;

1824

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

1825

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

1826

or tmpmax != (uint16_t)tmpmax){

1206

1827

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

1207

exitcode = EXIT_FAILURE;

1208

goto end;

1209

}

1828

exitcode = EX_USAGE;

1829

goto end;

1830

}

1831

1832

if(quit_now){

1833

goto end;

1834

}

1835

1210

1836

port = (uint16_t)tmpmax;

1211

1837

*address = '\0';

1212

address = connect_to;

1213

1838

/* Colon in address indicates IPv6 */

1214

1839

int af;

1215

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

1840

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

1216

1841

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

}

1217

1848

} else {

1218

1849

af = AF_INET;

1219

1850

}

1220

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

1221

if(ret < 0){

1222

exitcode = EXIT_FAILURE;

1223

} else {

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){

1224

1870

exitcode = EXIT_SUCCESS;

1225

1871

}

1226

goto end;

1227

}

1228

1872

1873

goto end;

1874

}

1875

1876

if(quit_now){

1877

goto end;

1878

}

1879

1229

1880

{

1230

1881

AvahiServerConfig config;

1231

1882

/* Do not publish any local Zeroconf records */

1248

1899

if(mc.server == NULL){

1249

1900

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

1250

1901

avahi_strerror(error));

1251

exitcode = EXIT_FAILURE;

1902

exitcode = EX_UNAVAILABLE;

1903

goto end;

1904

}

1905

1906

if(quit_now){

1252

1907

goto end;

1253

1908

}

1254

1909

1255

1910

/* Create the Avahi service browser */

1256

1911

sb = avahi_s_service_browser_new(mc.server, if_index,

1257

AVAHI_PROTO_INET6, "_mandos._tcp",

1912

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

1258

1913

NULL, 0, browse_callback, NULL);

1259

1914

if(sb == NULL){

1260

1915

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

1261

1916

avahi_strerror(avahi_server_errno(mc.server)));

1262

exitcode = EXIT_FAILURE;

1917

exitcode = EX_UNAVAILABLE;

1918

goto end;

1919

}

1920

1921

if(quit_now){

1263

1922

goto end;

1264

1923

}

1265

1924

1268

1927

if(debug){

1269

1928

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

1270

1929

}

1271

1272

avahi_simple_poll_loop(mc.simple_poll);

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

}

1273

1937

1274

1938

end:

1275

1939

1296

1960

if(gpgme_initialized){

1297

1961

gpgme_release(mc.ctx);

1298

1962

}

1299

1300

/* Removes the temp directory used by GPGME */

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 */

1301

2008

if(tempdir_created){

1302

DIR *d;

1303

struct dirent *direntry;

1304

d = opendir(tempdir);

1305

if(d == NULL){

1306

if(errno != ENOENT){

1307

perror("opendir");

1308

}

1309

} else {

1310

while(true){

1311

direntry = readdir(d);

1312

if(direntry == NULL){

1313

break;

1314

}

1315

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

1316

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

1317

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

1318

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

1319

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

1320

continue;

1321

}

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];

1322

2016

char *fullname = NULL;

1323

2017

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

1324

2018

direntry->d_name);

1325

2019

if(ret < 0){

1326

perror("asprintf");

2020

perror_plus("asprintf");

1327

2021

continue;

1328

2022

}

1329

2023

ret = remove(fullname);

1333

2027

}

1334

2028

free(fullname);

1335

2029

}

1336

closedir(d);

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");

1337

2036

}

1338

2037

ret = rmdir(tempdir);

1339

2038

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

1340

perror("rmdir");

1341

}

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());

1342

2060

}

1343

2061

1344

2062

return exitcode;