/mandos/trunk : revision 487

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

39

43

stdout, ferror(), remove() */

40

44

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

41

45

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

42

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

43

srand(), strtof() */

46

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

47

strtof(), abort() */

44

48

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

45

49

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

46

50

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

58

62

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

59

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

int add_server(const char *ip, uint16_t port,

191

AvahiIfIndex if_index,

192

int af){

193

int ret;

194

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

195

if(new_server == NULL){

196

perror_plus("malloc");

197

return -1;

198

}

199

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

200

.port = port,

201

.if_index = if_index,

202

.af = af };

203

if(new_server->ip == NULL){

204

perror_plus("strdup");

205

return -1;

206

}

207

/* unique case of first server */

208

if (mc.current_server == NULL){

209

new_server->next = new_server;

210

new_server->prev = new_server;

211

mc.current_server = new_server;

212

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

213

} else {

214

new_server->next = mc.current_server;

215

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

216

new_server->prev->next = new_server;

217

mc.current_server->prev = new_server;

218

}

219

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

220

if(ret == -1){

221

perror_plus("clock_gettime");

222

return -1;

223

}

224

return 0;

225

}

226

158

227

/*

159

228

* Initialize GPGME.

160

229

*/

161

230

static bool init_gpgme(const char *seckey,

162

231

const char *pubkey, const char *tempdir){

163

int ret;

164

232

gpgme_error_t rc;

165

233

gpgme_engine_info_t engine_info;

166

234

169

237

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

170

238

*/

171

239

bool import_key(const char *filename){

240

int ret;

172

241

int fd;

173

242

gpgme_data_t pgp_data;

174

243

175

244

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

176

245

if(fd == -1){

177

perror("open");

246

perror_plus("open");

178

247

return false;

179

248

}

180

249

194

263

195

264

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

196

265

if(ret == -1){

197

perror("close");

266

perror_plus("close");

198

267

}

199

268

gpgme_data_release(pgp_data);

200

269

return true;

245

314

return false;

246

315

}

247

316

248

return true;

317

return true;

249

318

}

250

319

251

320

/*

305

374

}

306

375

gpgme_recipient_t recipient;

307

376

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

}

377

while(recipient != NULL){

378

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

379

gpgme_pubkey_algo_name(recipient->pubkey_algo));

380

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

381

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

382

recipient->status == GPG_ERR_NO_SECKEY

383

? "No" : "Yes");

384

recipient = recipient->next;

318

385

}

319

386

}

320

387

}

327

394

328

395

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

329

396

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

330

perror("gpgme_data_seek");

397

perror_plus("gpgme_data_seek");

331

398

plaintext_length = -1;

332

399

goto decrypt_end;

333

400

}

338

405

(size_t)plaintext_length,

339

406

plaintext_capacity);

340

407

if(plaintext_capacity == 0){

341

perror("incbuffer");

408

perror_plus("incbuffer");

342

409

plaintext_length = -1;

343

410

goto decrypt_end;

344

411

}

351

418

break;

352

419

}

353

420

if(ret < 0){

354

perror("gpgme_data_read");

421

perror_plus("gpgme_data_read");

355

422

plaintext_length = -1;

356

423

goto decrypt_end;

357

424

}

414

481

}

415

482

416

483

/* OpenPGP credentials */

417

gnutls_certificate_allocate_credentials(&mc.cred);

484

ret = gnutls_certificate_allocate_credentials(&mc.cred);

418

485

if(ret != GNUTLS_E_SUCCESS){

419

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

420

from

421

-Wunreachable-code

422

*/

486

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

423

487

safer_gnutls_strerror(ret));

424

488

gnutls_global_deinit();

425

489

return -1;

472

536

static int init_gnutls_session(gnutls_session_t *session){

473

537

int ret;

474

538

/* GnuTLS session creation */

475

ret = gnutls_init(session, GNUTLS_SERVER);

539

do {

540

ret = gnutls_init(session, GNUTLS_SERVER);

541

if(quit_now){

542

return -1;

543

}

544

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

476

545

if(ret != GNUTLS_E_SUCCESS){

477

546

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

478

547

safer_gnutls_strerror(ret));

480

549

481

550

{

482

551

const char *err;

483

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

552

do {

553

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

554

if(quit_now){

555

gnutls_deinit(*session);

556

return -1;

557

}

558

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

484

559

if(ret != GNUTLS_E_SUCCESS){

485

560

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

486

561

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

490

565

}

491

566

}

492

567

493

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

494

mc.cred);

568

do {

569

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

570

mc.cred);

571

if(quit_now){

572

gnutls_deinit(*session);

573

return -1;

574

}

575

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

495

576

if(ret != GNUTLS_E_SUCCESS){

496

577

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

497

578

safer_gnutls_strerror(ret));

500

581

}

501

582

502

583

/* ignore client certificate if any. */

503

gnutls_certificate_server_set_request(*session,

504

GNUTLS_CERT_IGNORE);

584

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

505

585

506

586

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

507

587

516

596

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

517

597

AvahiIfIndex if_index,

518

598

int af){

519

int ret, tcp_sd;

599

int ret, tcp_sd = -1;

520

600

ssize_t sret;

521

601

union {

522

602

struct sockaddr_in in;

523

603

struct sockaddr_in6 in6;

524

604

} to;

525

605

char *buffer = NULL;

526

char *decrypted_buffer;

606

char *decrypted_buffer = NULL;

527

607

size_t buffer_length = 0;

528

608

size_t buffer_capacity = 0;

529

ssize_t decrypted_buffer_size;

530

609

size_t written;

531

int retval = 0;

610

int retval = -1;

532

611

gnutls_session_t session;

533

612

int pf; /* Protocol family */

534

613

614

errno = 0;

615

616

if(quit_now){

617

errno = EINTR;

618

return -1;

619

}

620

535

621

switch(af){

536

622

case AF_INET6:

537

623

pf = PF_INET6;

541

627

break;

542

628

default:

543

629

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

630

errno = EINVAL;

544

631

return -1;

545

632

}

546

633

556

643

557

644

tcp_sd = socket(pf, SOCK_STREAM, 0);

558

645

if(tcp_sd < 0){

559

perror("socket");

560

return -1;

646

int e = errno;

647

perror_plus("socket");

648

errno = e;

649

goto mandos_end;

650

}

651

652

if(quit_now){

653

errno = EINTR;

654

goto mandos_end;

561

655

}

562

656

563

657

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

564

658

if(af == AF_INET6){

565

to.in6.sin6_family = (uint16_t)af;

659

to.in6.sin6_family = (sa_family_t)af;

566

660

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

567

661

} else { /* IPv4 */

568

662

to.in.sin_family = (sa_family_t)af;

569

663

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

570

664

}

571

665

if(ret < 0 ){

572

perror("inet_pton");

573

return -1;

666

int e = errno;

667

perror_plus("inet_pton");

668

errno = e;

669

goto mandos_end;

574

670

}

575

671

if(ret == 0){

672

int e = errno;

576

673

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

577

return -1;

674

errno = e;

675

goto mandos_end;

578

676

}

579

677

if(af == AF_INET6){

580

678

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

587

685

if(if_index == AVAHI_IF_UNSPEC){

588

686

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

589

687

" without a network interface\n");

590

return -1;

688

errno = EINVAL;

689

goto mandos_end;

591

690

}

592

691

/* Set the network interface number as scope */

593

692

to.in6.sin6_scope_id = (uint32_t)if_index;

598

697

-Wunreachable-code */

599

698

}

600

699

700

if(quit_now){

701

errno = EINTR;

702

goto mandos_end;

703

}

704

601

705

if(debug){

602

706

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

603

707

char interface[IF_NAMESIZE];

604

708

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

605

perror("if_indextoname");

709

perror_plus("if_indextoname");

606

710

} else {

607

711

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

608

712

ip, interface, port);

622

726

sizeof(addrstr));

623

727

}

624

728

if(pcret == NULL){

625

perror("inet_ntop");

729

perror_plus("inet_ntop");

626

730

} else {

627

731

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

628

732

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

630

734

}

631

735

}

632

736

737

if(quit_now){

738

errno = EINTR;

739

goto mandos_end;

740

}

741

633

742

if(af == AF_INET6){

634

743

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

635

744

} else {

636

745

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

637

746

}

638

747

if(ret < 0){

639

perror("connect");

640

return -1;

748

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

749

int e = errno;

750

perror_plus("connect");

751

errno = e;

752

}

753

goto mandos_end;

754

}

755

756

if(quit_now){

757

errno = EINTR;

758

goto mandos_end;

641

759

}

642

760

643

761

const char *out = mandos_protocol_version;

647

765

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

648

766

out_size - written));

649

767

if(ret == -1){

650

perror("write");

651

retval = -1;

768

int e = errno;

769

perror_plus("write");

770

errno = e;

652

771

goto mandos_end;

653

772

}

654

773

written += (size_t)ret;

662

781

break;

663

782

}

664

783

}

784

785

if(quit_now){

786

errno = EINTR;

787

goto mandos_end;

788

}

665

789

}

666

790

667

791

if(debug){

668

792

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

669

793

}

670

794

795

if(quit_now){

796

errno = EINTR;

797

goto mandos_end;

798

}

799

800

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

671

801

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

672

802

673

do{

803

if(quit_now){

804

errno = EINTR;

805

goto mandos_end;

806

}

807

808

do {

674

809

ret = gnutls_handshake(session);

810

if(quit_now){

811

errno = EINTR;

812

goto mandos_end;

813

}

675

814

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

676

815

677

816

if(ret != GNUTLS_E_SUCCESS){

679

818

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

680

819

gnutls_perror(ret);

681

820

}

682

retval = -1;

821

errno = EPROTO;

683

822

goto mandos_end;

684

823

}

685

824

691

830

}

692

831

693

832

while(true){

833

834

if(quit_now){

835

errno = EINTR;

836

goto mandos_end;

837

}

838

694

839

buffer_capacity = incbuffer(&buffer, buffer_length,

695

840

buffer_capacity);

696

841

if(buffer_capacity == 0){

697

perror("incbuffer");

698

retval = -1;

842

int e = errno;

843

perror_plus("incbuffer");

844

errno = e;

845

goto mandos_end;

846

}

847

848

if(quit_now){

849

errno = EINTR;

699

850

goto mandos_end;

700

851

}

701

852

710

861

case GNUTLS_E_AGAIN:

711

862

break;

712

863

case GNUTLS_E_REHANDSHAKE:

713

do{

864

do {

714

865

ret = gnutls_handshake(session);

866

867

if(quit_now){

868

errno = EINTR;

869

goto mandos_end;

870

}

715

871

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

716

872

if(ret < 0){

717

873

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

718

874

gnutls_perror(ret);

719

retval = -1;

875

errno = EPROTO;

720

876

goto mandos_end;

721

877

}

722

878

break;

723

879

default:

724

880

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

725

881

" encrypted session with Mandos server\n");

726

retval = -1;

727

882

gnutls_bye(session, GNUTLS_SHUT_RDWR);

883

errno = EIO;

728

884

goto mandos_end;

729

885

}

730

886

} else {

736

892

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

737

893

}

738

894

739

gnutls_bye(session, GNUTLS_SHUT_RDWR);

895

if(quit_now){

896

errno = EINTR;

897

goto mandos_end;

898

}

899

900

do {

901

ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);

902

if(quit_now){

903

errno = EINTR;

904

goto mandos_end;

905

}

906

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

740

907

741

908

if(buffer_length > 0){

909

ssize_t decrypted_buffer_size;

742

910

decrypted_buffer_size = pgp_packet_decrypt(buffer,

743

911

buffer_length,

744

912

&decrypted_buffer);

745

913

if(decrypted_buffer_size >= 0){

914

746

915

written = 0;

747

916

while(written < (size_t) decrypted_buffer_size){

917

if(quit_now){

918

errno = EINTR;

919

goto mandos_end;

920

}

921

748

922

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

749

923

(size_t)decrypted_buffer_size - written,

750

924

stdout);

751

925

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

926

int e = errno;

752

927

if(debug){

753

928

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

754

929

strerror(errno));

755

930

}

756

retval = -1;

757

break;

931

errno = e;

932

goto mandos_end;

758

933

}

759

934

written += (size_t)ret;

760

935

}

761

free(decrypted_buffer);

762

} else {

763

retval = -1;

936

retval = 0;

764

937

}

765

} else {

766

retval = -1;

767

938

}

768

939

769

940

/* Shutdown procedure */

770

941

771

942

mandos_end:

772

free(buffer);

773

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

774

if(ret == -1){

775

perror("close");

943

{

944

int e = errno;

945

free(decrypted_buffer);

946

free(buffer);

947

if(tcp_sd >= 0){

948

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

949

}

950

if(ret == -1){

951

if(e == 0){

952

e = errno;

953

}

954

perror_plus("close");

955

}

956

gnutls_deinit(session);

957

errno = e;

958

if(quit_now){

959

errno = EINTR;

960

retval = -1;

961

}

776

962

}

777

gnutls_deinit(session);

778

963

return retval;

779

964

}

780

965

797

982

/* Called whenever a service has been resolved successfully or

798

983

timed out */

799

984

985

if(quit_now){

986

return;

987

}

988

800

989

switch(event){

801

990

default:

802

991

case AVAHI_RESOLVER_FAILURE:

818

1007

avahi_proto_to_af(proto));

819

1008

if(ret == 0){

820

1009

avahi_simple_poll_quit(mc.simple_poll);

1010

} else {

1011

ret = add_server(ip, port, interface,

1012

avahi_proto_to_af(proto));

821

1013

}

822

1014

}

823

1015

}

839

1031

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

840

1032

is removed from the LAN */

841

1033

1034

if(quit_now){

1035

return;

1036

}

1037

842

1038

switch(event){

843

1039

default:

844

1040

case AVAHI_BROWSER_FAILURE:

854

1050

the callback function is called the Avahi server will free the

855

1051

resolver for us. */

856

1052

857

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

858

protocol, name, type, domain,

859

AVAHI_PROTO_INET6, 0,

860

resolve_callback, NULL)))

1053

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

1054

name, type, domain, protocol, 0,

1055

resolve_callback, NULL) == NULL)

861

1056

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

862

1057

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

863

1058

break;

874

1069

}

875

1070

}

876

1071

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){

1072

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

1073

static void handle_sigterm(int sig){

881

1074

if(quit_now){

882

1075

return;

883

1076

}

884

1077

quit_now = 1;

1078

signal_received = sig;

885

1079

int old_errno = errno;

1080

/* set main loop to exit */

886

1081

if(mc.simple_poll != NULL){

887

1082

avahi_simple_poll_quit(mc.simple_poll);

888

1083

}

889

1084

errno = old_errno;

890

1085

}

891

1086

1087

/*

1088

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

1089

* corresponds to an acceptable network device.

1090

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

1091

*/

1092

int good_interface(const struct dirent *if_entry){

1093

ssize_t ssret;

1094

char *flagname = NULL;

1095

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

1096

return 0;

1097

}

1098

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

1099

if_entry->d_name);

1100

if(ret < 0){

1101

perror_plus("asprintf");

1102

return 0;

1103

}

1104

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

1105

if(flags_fd == -1){

1106

perror_plus("open");

1107

free(flagname);

1108

return 0;

1109

}

1110

free(flagname);

1111

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

1112

/* read line from flags_fd */

1113

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

1114

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

1115

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

1116

if(flagstring == NULL){

1117

perror_plus("malloc");

1118

close(flags_fd);

1119

return 0;

1120

}

1121

while(to_read > 0){

1122

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

1123

(size_t)to_read));

1124

if(ssret == -1){

1125

perror_plus("read");

1126

free(flagstring);

1127

close(flags_fd);

1128

return 0;

1129

}

1130

to_read -= ssret;

1131

if(ssret == 0){

1132

break;

1133

}

1134

}

1135

close(flags_fd);

1136

intmax_t tmpmax;

1137

char *tmp;

1138

errno = 0;

1139

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

1140

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

1141

and not (isspace(*tmp)))

1142

or tmpmax != (ifreq_flags)tmpmax){

1143

if(debug){

1144

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

1145

flagstring, if_entry->d_name);

1146

}

1147

free(flagstring);

1148

return 0;

1149

}

1150

free(flagstring);

1151

ifreq_flags flags = (ifreq_flags)tmpmax;

1152

/* Reject the loopback device */

1153

if(flags & IFF_LOOPBACK){

1154

if(debug){

1155

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

1156

if_entry->d_name);

1157

}

1158

return 0;

1159

}

1160

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

1161

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

1162

if(debug){

1163

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

1164

if_entry->d_name);

1165

}

1166

return 1;

1167

}

1168

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

1169

if(not (flags & IFF_BROADCAST)){

1170

if(debug){

1171

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

1172

if_entry->d_name);

1173

}

1174

return 0;

1175

}

1176

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

1177

if(flags & IFF_NOARP){

1178

if(debug){

1179

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

1180

if_entry->d_name);

1181

}

1182

return 0;

1183

}

1184

/* Accept this device */

1185

if(debug){

1186

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

1187

if_entry->d_name);

1188

}

1189

return 1;

1190

}

1191

1192

int notdotentries(const struct dirent *direntry){

1193

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

1194

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

1195

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

1196

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

1197

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

1198

return 0;

1199

}

1200

return 1;

1201

}

1202

1203

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1204

int ret;

1205

struct timespec now;

1206

struct timespec waited_time;

1207

intmax_t block_time;

1208

1209

while(true){

1210

if(mc.current_server == NULL){

1211

if (debug){

1212

fprintf(stderr,

1213

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

1214

}

1215

ret = avahi_simple_poll_iterate(s, -1);

1216

} else {

1217

if (debug){

1218

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

1219

" or wait\n");

1220

}

1221

/* the current time */

1222

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1223

if(ret == -1){

1224

perror_plus("clock_gettime");

1225

return -1;

1226

}

1227

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

1228

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

1229

waited_time.tv_sec = (now.tv_sec

1230

- mc.current_server->last_seen.tv_sec);

1231

waited_time.tv_nsec = (now.tv_nsec

1232

- mc.current_server->last_seen.tv_nsec);

1233

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

1234

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

1235

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

1236

block_time = ((retry_interval

1237

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

1238

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

1239

1240

if (debug){

1241

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

1242

}

1243

1244

if(block_time <= 0){

1245

ret = start_mandos_communication(mc.current_server->ip,

1246

mc.current_server->port,

1247

mc.current_server->if_index,

1248

mc.current_server->af);

1249

if(ret == 0){

1250

avahi_simple_poll_quit(mc.simple_poll);

1251

return 0;

1252

}

1253

ret = clock_gettime(CLOCK_MONOTONIC,

1254

&mc.current_server->last_seen);

1255

if(ret == -1){

1256

perror_plus("clock_gettime");

1257

return -1;

1258

}

1259

mc.current_server = mc.current_server->next;

1260

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

1261

servers, but don't block */

1262

}

1263

1264

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

1265

}

1266

if(ret != 0){

1267

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

1268

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

1269

}

1270

}

1271

}

1272

}

1273

892

1274

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

893

1275

AvahiSServiceBrowser *sb = NULL;

894

1276

int error;

896

1278

intmax_t tmpmax;

897

1279

char *tmp;

898

1280

int exitcode = EXIT_SUCCESS;

899

const char *interface = "eth0";

1281

const char *interface = "";

900

1282

struct ifreq network;

901

int sd;

1283

int sd = -1;

1284

bool take_down_interface = false;

902

1285

uid_t uid;

903

1286

gid_t gid;

904

char *connect_to = NULL;

905

1287

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

906

1288

bool tempdir_created = false;

907

1289

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

908

1290

const char *seckey = PATHDIR "/" SECKEY;

909

1291

const char *pubkey = PATHDIR "/" PUBKEY;

910

1292

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

1293

bool gnutls_initialized = false;

916

1294

bool gpgme_initialized = false;

917

1295

float delay = 2.5f;

1296

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

1297

retrying the same server again */

918

1298

919

struct sigaction old_sigterm_action;

1299

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

920

1300

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

921

1301

1302

uid = getuid();

1303

gid = getgid();

1304

1305

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

1306

errno = 0;

1307

ret = setgid(gid);

1308

if(ret == -1){

1309

perror_plus("setgid");

1310

}

1311

1312

/* Lower user privileges (temporarily) */

1313

errno = 0;

1314

ret = seteuid(uid);

1315

if(ret == -1){

1316

perror_plus("seteuid");

1317

}

1318

1319

if(quit_now){

1320

goto end;

1321

}

1322

922

1323

{

923

1324

struct argp_option options[] = {

924

1325

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

953

1354

.arg = "SECONDS",

954

1355

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

955

1356

.group = 2 },

1357

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

1358

.arg = "SECONDS",

1359

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

1360

.group = 2 },

1361

/*

1362

* These reproduce what we would get without ARGP_NO_HELP

1363

*/

1364

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

1365

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

1366

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

1367

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

1368

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

1369

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

956

1370

{ .name = NULL }

957

1371

};

958

1372

959

1373

error_t parse_opt(int key, char *arg,

960

1374

struct argp_state *state){

1375

errno = 0;

961

1376

switch(key){

962

1377

case 128: /* --debug */

963

1378

debug = true;

979

1394

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

980

1395

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

981

1396

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

982

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

983

exit(EXIT_FAILURE);

1397

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

984

1398

}

985

1399

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

986

1400

break;

991

1405

errno = 0;

992

1406

delay = strtof(arg, &tmp);

993

1407

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

994

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

995

exit(EXIT_FAILURE);

1408

argp_error(state, "Bad delay");

1409

}

1410

case 132: /* --retry */

1411

errno = 0;

1412

retry_interval = strtod(arg, &tmp);

1413

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

1414

or (retry_interval * 1000) > INT_MAX){

1415

argp_error(state, "Bad retry interval");

996

1416

}

997

1417

break;

998

case ARGP_KEY_ARG:

999

argp_usage(state);

1000

case ARGP_KEY_END:

1418

/*

1419

* These reproduce what we would get without ARGP_NO_HELP

1420

*/

1421

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

1422

argp_state_help(state, state->out_stream,

1423

(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)

1424

& ~(unsigned int)ARGP_HELP_EXIT_OK);

1425

case -3: /* --usage */

1426

argp_state_help(state, state->out_stream,

1427

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1428

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

1429

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

1430

exit(argp_err_exit_status);

1001

1431

break;

1002

1432

default:

1003

1433

return ARGP_ERR_UNKNOWN;

1004

1434

}

1005

return 0;

1435

return errno;

1006

1436

}

1007

1437

1008

1438

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

1009

1439

.args_doc = "",

1010

1440

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

1011

1441

" passwords from a Mandos server" };

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;

1442

ret = argp_parse(&argp, argc, argv,

1443

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1444

switch(ret){

1445

case 0:

1446

break;

1447

case ENOMEM:

1448

default:

1449

errno = ret;

1450

perror_plus("argp_parse");

1451

exitcode = EX_OSERR;

1452

goto end;

1453

case EINVAL:

1454

exitcode = EX_USAGE;

1455

goto end;

1456

}

1457

}

1458

1459

{

1460

/* Work around Debian bug #633582:

1461

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

1462

struct stat st;

1463

1464

/* Re-raise priviliges */

1465

errno = 0;

1466

ret = seteuid(0);

1467

if(ret == -1){

1468

perror_plus("seteuid");

1469

}

1470

1471

int seckey_fd = open(PATHDIR "/" SECKEY, O_RDONLY);

1472

if(seckey_fd == -1){

1473

perror_plus("open");

1474

} else {

1475

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

1476

if(ret == -1){

1477

perror_plus("fstat");

1478

} else {

1479

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

1480

ret = fchown(seckey_fd, uid, gid);

1481

if(ret == -1){

1482

perror_plus("fchown");

1483

}

1484

}

1485

}

1486

TEMP_FAILURE_RETRY(close(seckey_fd));

1487

}

1488

1489

int pubkey_fd = open(PATHDIR "/" PUBKEY, O_RDONLY);

1490

if(pubkey_fd == -1){

1491

perror_plus("open");

1492

} else {

1493

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

1494

if(ret == -1){

1495

perror_plus("fstat");

1496

} else {

1497

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

1498

ret = fchown(pubkey_fd, uid, gid);

1499

if(ret == -1){

1500

perror_plus("fchown");

1501

}

1502

}

1503

}

1504

TEMP_FAILURE_RETRY(close(pubkey_fd));

1505

}

1506

1507

/* Lower privileges */

1508

errno = 0;

1509

ret = seteuid(uid);

1510

if(ret == -1){

1511

perror_plus("seteuid");

1017

1512

}

1018

1513

}

1019

1514

1020

1515

if(not debug){

1021

1516

avahi_set_log_function(empty_log);

1022

1517

}

1518

1519

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

1520

struct dirent **direntries;

1521

ret = scandir(sys_class_net, &direntries, good_interface,

1522

alphasort);

1523

if(ret >= 1){

1524

/* Pick the first good interface */

1525

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

1526

if(debug){

1527

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

1528

}

1529

if(interface == NULL){

1530

perror_plus("malloc");

1531

free(direntries);

1532

exitcode = EXIT_FAILURE;

1533

goto end;

1534

}

1535

free(direntries);

1536

} else {

1537

free(direntries);

1538

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

1539

exitcode = EXIT_FAILURE;

1540

goto end;

1541

}

1542

}

1023

1543

1024

1544

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

1025

1545

from the signal handler */

1028

1548

mc.simple_poll = avahi_simple_poll_new();

1029

1549

if(mc.simple_poll == NULL){

1030

1550

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

1031

exitcode = EXIT_FAILURE;

1551

exitcode = EX_UNAVAILABLE;

1032

1552

goto end;

1033

1553

}

1034

1554

1035

1555

sigemptyset(&sigterm_action.sa_mask);

1036

1556

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

1037

1557

if(ret == -1){

1038

perror("sigaddset");

1039

exitcode = EXIT_FAILURE;

1558

perror_plus("sigaddset");

1559

exitcode = EX_OSERR;

1040

1560

goto end;

1041

1561

}

1042

1562

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

1043

1563

if(ret == -1){

1044

perror("sigaddset");

1045

exitcode = EXIT_FAILURE;

1564

perror_plus("sigaddset");

1565

exitcode = EX_OSERR;

1046

1566

goto end;

1047

1567

}

1048

1568

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

1049

1569

if(ret == -1){

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

}

1570

perror_plus("sigaddset");

1571

exitcode = EX_OSERR;

1572

goto end;

1573

}

1574

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

1575

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

1576

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

1577

*/

1578

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

1579

if(ret == -1){

1580

perror_plus("sigaction");

1581

return EX_OSERR;

1582

}

1583

if(old_sigterm_action.sa_handler != SIG_IGN){

1584

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

1585

if(ret == -1){

1586

perror_plus("sigaction");

1587

exitcode = EX_OSERR;

1588

goto end;

1589

}

1590

}

1591

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

1592

if(ret == -1){

1593

perror_plus("sigaction");

1594

return EX_OSERR;

1595

}

1596

if(old_sigterm_action.sa_handler != SIG_IGN){

1597

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

1598

if(ret == -1){

1599

perror_plus("sigaction");

1600

exitcode = EX_OSERR;

1601

goto end;

1602

}

1603

}

1604

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

1605

if(ret == -1){

1606

perror_plus("sigaction");

1607

return EX_OSERR;

1608

}

1609

if(old_sigterm_action.sa_handler != SIG_IGN){

1610

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

1611

if(ret == -1){

1612

perror_plus("sigaction");

1613

exitcode = EX_OSERR;

1614

goto end;

1615

}

1616

}

1060

1617

1061

1618

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

1062

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

1619

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

1620

if_index = (AvahiIfIndex) if_nametoindex(interface);

1621

if(if_index == 0){

1622

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

1623

exitcode = EX_UNAVAILABLE;

1624

goto end;

1625

}

1626

1627

if(quit_now){

1628

goto end;

1629

}

1630

1631

/* Re-raise priviliges */

1632

errno = 0;

1633

ret = seteuid(0);

1634

if(ret == -1){

1635

perror_plus("seteuid");

1636

}

1637

1063

1638

#ifdef __linux__

1064

1639

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1065

messages to mess up the prompt */

1640

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

1066

1641

ret = klogctl(8, NULL, 5);

1067

1642

bool restore_loglevel = true;

1068

1643

if(ret == -1){

1069

1644

restore_loglevel = false;

1070

perror("klogctl");

1645

perror_plus("klogctl");

1071

1646

}

1072

1647

#endif /* __linux__ */

1073

1648

1074

1649

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1075

1650

if(sd < 0){

1076

perror("socket");

1077

exitcode = EXIT_FAILURE;

1651

perror_plus("socket");

1652

exitcode = EX_OSERR;

1078

1653

#ifdef __linux__

1079

1654

if(restore_loglevel){

1080

1655

ret = klogctl(7, NULL, 0);

1081

1656

if(ret == -1){

1082

perror("klogctl");

1657

perror_plus("klogctl");

1083

1658

}

1084

1659

}

1085

1660

#endif /* __linux__ */

1661

/* Lower privileges */

1662

errno = 0;

1663

ret = seteuid(uid);

1664

if(ret == -1){

1665

perror_plus("seteuid");

1666

}

1086

1667

goto end;

1087

1668

}

1088

1669

strcpy(network.ifr_name, interface);

1089

1670

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

1090

1671

if(ret == -1){

1091

perror("ioctl SIOCGIFFLAGS");

1672

perror_plus("ioctl SIOCGIFFLAGS");

1092

1673

#ifdef __linux__

1093

1674

if(restore_loglevel){

1094

1675

ret = klogctl(7, NULL, 0);

1095

1676

if(ret == -1){

1096

perror("klogctl");

1677

perror_plus("klogctl");

1097

1678

}

1098

1679

}

1099

1680

#endif /* __linux__ */

1100

exitcode = EXIT_FAILURE;

1681

exitcode = EX_OSERR;

1682

/* Lower privileges */

1683

errno = 0;

1684

ret = seteuid(uid);

1685

if(ret == -1){

1686

perror_plus("seteuid");

1687

}

1101

1688

goto end;

1102

1689

}

1103

1690

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

1104

1691

network.ifr_flags |= IFF_UP;

1692

take_down_interface = true;

1105

1693

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

1106

1694

if(ret == -1){

1107

perror("ioctl SIOCSIFFLAGS");

1108

exitcode = EXIT_FAILURE;

1695

take_down_interface = false;

1696

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1697

exitcode = EX_OSERR;

1109

1698

#ifdef __linux__

1110

1699

if(restore_loglevel){

1111

1700

ret = klogctl(7, NULL, 0);

1112

1701

if(ret == -1){

1113

perror("klogctl");

1702

perror_plus("klogctl");

1114

1703

}

1115

1704

}

1116

1705

#endif /* __linux__ */

1706

/* Lower privileges */

1707

errno = 0;

1708

ret = seteuid(uid);

1709

if(ret == -1){

1710

perror_plus("seteuid");

1711

}

1117

1712

goto end;

1118

1713

}

1119

1714

}

1120

/* sleep checking until interface is running */

1715

/* Sleep checking until interface is running.

1716

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

1121

1717

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

1122

1718

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

1123

1719

if(ret == -1){

1124

perror("ioctl SIOCGIFFLAGS");

1720

perror_plus("ioctl SIOCGIFFLAGS");

1125

1721

} else if(network.ifr_flags & IFF_RUNNING){

1126

1722

break;

1127

1723

}

1128

1724

struct timespec sleeptime = { .tv_nsec = 250000000 };

1129

1725

ret = nanosleep(&sleeptime, NULL);

1130

1726

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

1131

perror("nanosleep");

1727

perror_plus("nanosleep");

1132

1728

}

1133

1729

}

1134

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

1135

if(ret == -1){

1136

perror("close");

1730

if(not take_down_interface){

1731

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

1732

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

1733

if(ret == -1){

1734

perror_plus("close");

1735

}

1137

1736

}

1138

1737

#ifdef __linux__

1139

1738

if(restore_loglevel){

1140

1739

/* Restores kernel loglevel to default */

1141

1740

ret = klogctl(7, NULL, 0);

1142

1741

if(ret == -1){

1143

perror("klogctl");

1742

perror_plus("klogctl");

1144

1743

}

1145

1744

}

1146

1745

#endif /* __linux__ */

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");

1746

/* Lower privileges */

1747

errno = 0;

1748

if(take_down_interface){

1749

/* Lower privileges */

1750

ret = seteuid(uid);

1751

if(ret == -1){

1752

perror_plus("seteuid");

1753

}

1754

} else {

1755

/* Lower privileges permanently */

1756

ret = setuid(uid);

1757

if(ret == -1){

1758

perror_plus("setuid");

1759

}

1760

}

1761

}

1762

1763

if(quit_now){

1764

goto end;

1161

1765

}

1162

1766

1163

1767

ret = init_gnutls_global(pubkey, seckey);

1164

1768

if(ret == -1){

1165

1769

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

1166

exitcode = EXIT_FAILURE;

1770

exitcode = EX_UNAVAILABLE;

1167

1771

goto end;

1168

1772

} else {

1169

1773

gnutls_initialized = true;

1170

1774

}

1171

1775

1776

if(quit_now){

1777

goto end;

1778

}

1779

1172

1780

if(mkdtemp(tempdir) == NULL){

1173

perror("mkdtemp");

1781

perror_plus("mkdtemp");

1174

1782

goto end;

1175

1783

}

1176

1784

tempdir_created = true;

1177

1785

1786

if(quit_now){

1787

goto end;

1788

}

1789

1178

1790

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

1179

1791

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

1180

exitcode = EXIT_FAILURE;

1792

exitcode = EX_UNAVAILABLE;

1181

1793

goto end;

1182

1794

} else {

1183

1795

gpgme_initialized = true;

1184

1796

}

1185

1797

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

}

1798

if(quit_now){

1799

goto end;

1193

1800

}

1194

1801

1195

1802

if(connect_to != NULL){

1198

1805

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

1199

1806

if(address == NULL){

1200

1807

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

1201

exitcode = EXIT_FAILURE;

1202

goto end;

1203

}

1808

exitcode = EX_USAGE;

1809

goto end;

1810

}

1811

1812

if(quit_now){

1813

goto end;

1814

}

1815

1204

1816

uint16_t port;

1205

1817

errno = 0;

1206

1818

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

1207

1819

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

1208

1820

or tmpmax != (uint16_t)tmpmax){

1209

1821

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

1210

exitcode = EXIT_FAILURE;

1211

goto end;

1212

}

1822

exitcode = EX_USAGE;

1823

goto end;

1824

}

1825

1826

if(quit_now){

1827

goto end;

1828

}

1829

1213

1830

port = (uint16_t)tmpmax;

1214

1831

*address = '\0';

1215

1832

address = connect_to;

1220

1837

} else {

1221

1838

af = AF_INET;

1222

1839

}

1223

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

1224

if(ret < 0){

1225

exitcode = EXIT_FAILURE;

1226

} else {

1840

1841

if(quit_now){

1842

goto end;

1843

}

1844

1845

while(not quit_now){

1846

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

1847

if(quit_now or ret == 0){

1848

break;

1849

}

1850

sleep((int)retry_interval or 1);

1851

};

1852

1853

if (not quit_now){

1227

1854

exitcode = EXIT_SUCCESS;

1228

1855

}

1229

goto end;

1230

}

1231

1856

1857

goto end;

1858

}

1859

1860

if(quit_now){

1861

goto end;

1862

}

1863

1232

1864

{

1233

1865

AvahiServerConfig config;

1234

1866

/* Do not publish any local Zeroconf records */

1251

1883

if(mc.server == NULL){

1252

1884

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

1253

1885

avahi_strerror(error));

1254

exitcode = EXIT_FAILURE;

1886

exitcode = EX_UNAVAILABLE;

1887

goto end;

1888

}

1889

1890

if(quit_now){

1255

1891

goto end;

1256

1892

}

1257

1893

1258

1894

/* Create the Avahi service browser */

1259

1895

sb = avahi_s_service_browser_new(mc.server, if_index,

1260

AVAHI_PROTO_INET6, "_mandos._tcp",

1896

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

1261

1897

NULL, 0, browse_callback, NULL);

1262

1898

if(sb == NULL){

1263

1899

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

1264

1900

avahi_strerror(avahi_server_errno(mc.server)));

1265

exitcode = EXIT_FAILURE;

1901

exitcode = EX_UNAVAILABLE;

1902

goto end;

1903

}

1904

1905

if(quit_now){

1266

1906

goto end;

1267

1907

}

1268

1908

1271

1911

if(debug){

1272

1912

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

1273

1913

}

1274

1275

avahi_simple_poll_loop(mc.simple_poll);

1914

1915

ret = avahi_loop_with_timeout(mc.simple_poll,

1916

(int)(retry_interval * 1000));

1917

if(debug){

1918

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

1919

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

1920

}

1276

1921

1277

1922

end:

1278

1923

1299

1944

if(gpgme_initialized){

1300

1945

gpgme_release(mc.ctx);

1301

1946

}

1302

1303

/* Removes the temp directory used by GPGME */

1947

1948

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

1949

has seen */

1950

if(mc.current_server != NULL){

1951

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

1952

while(mc.current_server != NULL){

1953

server *next = mc.current_server->next;

1954

free(mc.current_server);

1955

mc.current_server = next;

1956

}

1957

}

1958

1959

/* Take down the network interface */

1960

if(take_down_interface){

1961

/* Re-raise priviliges */

1962

errno = 0;

1963

ret = seteuid(0);

1964

if(ret == -1){

1965

perror_plus("seteuid");

1966

}

1967

if(geteuid() == 0){

1968

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

1969

if(ret == -1){

1970

perror_plus("ioctl SIOCGIFFLAGS");

1971

} else if(network.ifr_flags & IFF_UP) {

1972

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

1973

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

1974

if(ret == -1){

1975

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1976

}

1977

}

1978

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

1979

if(ret == -1){

1980

perror_plus("close");

1981

}

1982

/* Lower privileges permanently */

1983

errno = 0;

1984

ret = setuid(uid);

1985

if(ret == -1){

1986

perror_plus("setuid");

1987

}

1988

}

1989

}

1990

1991

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

1304

1992

if(tempdir_created){

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

}

1993

struct dirent **direntries = NULL;

1994

struct dirent *direntry = NULL;

1995

ret = scandir(tempdir, &direntries, notdotentries, alphasort);

1996

if (ret > 0){

1997

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

1998

direntry = direntries[i];

1325

1999

char *fullname = NULL;

1326

2000

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

1327

2001

direntry->d_name);

1328

2002

if(ret < 0){

1329

perror("asprintf");

2003

perror_plus("asprintf");

1330

2004

continue;

1331

2005

}

1332

2006

ret = remove(fullname);

1336

2010

}

1337

2011

free(fullname);

1338

2012

}

1339

closedir(d);

2013

}

2014

2015

/* need to be cleaned even if ret == 0 because man page doesn't

2016

specify */

2017

free(direntries);

2018

if (ret == -1){

2019

perror_plus("scandir");

1340

2020

}

1341

2021

ret = rmdir(tempdir);

1342

2022

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

1343

perror("rmdir");

1344

}

2023

perror_plus("rmdir");

2024

}

2025

}

2026

2027

if(quit_now){

2028

sigemptyset(&old_sigterm_action.sa_mask);

2029

old_sigterm_action.sa_handler = SIG_DFL;

2030

ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,

2031

&old_sigterm_action,

2032

NULL));

2033

if(ret == -1){

2034

perror_plus("sigaction");

2035

}

2036

do {

2037

ret = raise(signal_received);

2038

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

2039

if(ret != 0){

2040

perror_plus("raise");

2041

abort();

2042

}

2043

TEMP_FAILURE_RETRY(pause());

1345

2044

}

1346

2045

1347

2046

return exitcode;