/mandos/release : revision 24.1.149

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

65

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

62

66

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

67

71

INET_ADDRSTRLEN, INET6_ADDRSTRLEN

68

72

*/

69

73

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

70

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

71

setgid() */

74

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

75

setgid(), pause() */

72

76

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

73

77

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

74

78

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

76

80

argp_parse(), ARGP_KEY_ARG,

77

81

ARGP_KEY_END, ARGP_ERR_UNKNOWN */

78

82

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

79

sigaction(), SIGTERM, sigaction */

83

sigaction(), SIGTERM, sig_atomic_t,

84

raise() */

85

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

86

EX_NOHOST, EX_IOERR, EX_PROTOCOL */

80

87

81

88

#ifdef __linux__

82

89

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

83

#endif

90

#endif /* __linux__ */

84

91

85

92

/* Avahi */

86

93

/* All Avahi types, constants and functions

133

140

} mandos_context;

134

141

135

142

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

136

mandos_context mc;

143

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

144

.dh_bits = 1024, .priority = "SECURE256"

145

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

146

147

sig_atomic_t quit_now = 0;

148

int signal_received = 0;

137

149

138

150

/*

139

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

140

* additional bytes. "buffer_capacity" is how much is currently

141

* allocated, "buffer_length" is how much is already used.

151

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

152

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

153

* "buffer_length" is how much is already used.

142

154

*/

143

155

size_t incbuffer(char **buffer, size_t buffer_length,

144

156

size_t buffer_capacity){

157

169

*/

158

170

static bool init_gpgme(const char *seckey,

159

171

const char *pubkey, const char *tempdir){

160

int ret;

161

172

gpgme_error_t rc;

162

173

gpgme_engine_info_t engine_info;

163

174

166

177

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

167

178

*/

168

179

bool import_key(const char *filename){

180

int ret;

169

181

int fd;

170

182

gpgme_data_t pgp_data;

171

183

242

254

return false;

243

255

}

244

256

245

return true;

257

return true;

246

258

}

247

259

248

260

/*

302

314

}

303

315

gpgme_recipient_t recipient;

304

316

recipient = result->recipients;

305

if(recipient){

306

while(recipient != NULL){

307

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

308

gpgme_pubkey_algo_name(recipient->pubkey_algo));

309

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

310

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

311

recipient->status == GPG_ERR_NO_SECKEY

312

? "No" : "Yes");

313

recipient = recipient->next;

314

}

317

while(recipient != NULL){

318

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

319

gpgme_pubkey_algo_name(recipient->pubkey_algo));

320

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

321

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

322

recipient->status == GPG_ERR_NO_SECKEY

323

? "No" : "Yes");

324

recipient = recipient->next;

315

325

}

316

326

}

317

327

}

469

479

static int init_gnutls_session(gnutls_session_t *session){

470

480

int ret;

471

481

/* GnuTLS session creation */

472

ret = gnutls_init(session, GNUTLS_SERVER);

482

do {

483

ret = gnutls_init(session, GNUTLS_SERVER);

484

if(quit_now){

485

return -1;

486

}

487

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

473

488

if(ret != GNUTLS_E_SUCCESS){

474

489

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

475

490

safer_gnutls_strerror(ret));

477

492

478

493

{

479

494

const char *err;

480

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

495

do {

496

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

497

if(quit_now){

498

gnutls_deinit(*session);

499

return -1;

500

}

501

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

481

502

if(ret != GNUTLS_E_SUCCESS){

482

503

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

483

504

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

487

508

}

488

509

}

489

510

490

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

491

mc.cred);

511

do {

512

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

513

mc.cred);

514

if(quit_now){

515

gnutls_deinit(*session);

516

return -1;

517

}

518

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

492

519

if(ret != GNUTLS_E_SUCCESS){

493

520

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

494

521

safer_gnutls_strerror(ret));

497

524

}

498

525

499

526

/* ignore client certificate if any. */

500

gnutls_certificate_server_set_request(*session,

501

GNUTLS_CERT_IGNORE);

527

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

502

528

503

529

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

504

530

513

539

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

514

540

AvahiIfIndex if_index,

515

541

int af){

516

int ret, tcp_sd;

542

int ret, tcp_sd = -1;

517

543

ssize_t sret;

518

544

union {

519

545

struct sockaddr_in in;

520

546

struct sockaddr_in6 in6;

521

547

} to;

522

548

char *buffer = NULL;

523

char *decrypted_buffer;

549

char *decrypted_buffer = NULL;

524

550

size_t buffer_length = 0;

525

551

size_t buffer_capacity = 0;

526

ssize_t decrypted_buffer_size;

527

552

size_t written;

528

int retval = 0;

553

int retval = -1;

529

554

gnutls_session_t session;

530

555

int pf; /* Protocol family */

531

556

557

errno = 0;

558

559

if(quit_now){

560

errno = EINTR;

561

return -1;

562

}

563

532

564

switch(af){

533

565

case AF_INET6:

534

566

pf = PF_INET6;

538

570

break;

539

571

default:

540

572

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

573

errno = EINVAL;

541

574

return -1;

542

575

}

543

576

553

586

554

587

tcp_sd = socket(pf, SOCK_STREAM, 0);

555

588

if(tcp_sd < 0){

589

int e = errno;

556

590

perror("socket");

557

return -1;

591

errno = e;

592

goto mandos_end;

593

}

594

595

if(quit_now){

596

errno = EINTR;

597

goto mandos_end;

558

598

}

559

599

560

600

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

561

601

if(af == AF_INET6){

562

to.in6.sin6_family = (uint16_t)af;

602

to.in6.sin6_family = (sa_family_t)af;

563

603

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

564

604

} else { /* IPv4 */

565

605

to.in.sin_family = (sa_family_t)af;

566

606

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

567

607

}

568

608

if(ret < 0 ){

609

int e = errno;

569

610

perror("inet_pton");

570

return -1;

611

errno = e;

612

goto mandos_end;

571

613

}

572

614

if(ret == 0){

615

int e = errno;

573

616

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

574

return -1;

617

errno = e;

618

goto mandos_end;

575

619

}

576

620

if(af == AF_INET6){

577

621

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

584

628

if(if_index == AVAHI_IF_UNSPEC){

585

629

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

586

630

" without a network interface\n");

587

return -1;

631

errno = EINVAL;

632

goto mandos_end;

588

633

}

589

634

/* Set the network interface number as scope */

590

635

to.in6.sin6_scope_id = (uint32_t)if_index;

595

640

-Wunreachable-code */

596

641

}

597

642

643

if(quit_now){

644

errno = EINTR;

645

goto mandos_end;

646

}

647

598

648

if(debug){

599

649

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

600

650

char interface[IF_NAMESIZE];

627

677

}

628

678

}

629

679

680

if(quit_now){

681

errno = EINTR;

682

goto mandos_end;

683

}

684

630

685

if(af == AF_INET6){

631

686

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

632

687

} else {

633

688

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

634

689

}

635

690

if(ret < 0){

691

int e = errno;

636

692

perror("connect");

637

return -1;

693

errno = e;

694

goto mandos_end;

695

}

696

697

if(quit_now){

698

errno = EINTR;

699

goto mandos_end;

638

700

}

639

701

640

702

const char *out = mandos_protocol_version;

644

706

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

645

707

out_size - written));

646

708

if(ret == -1){

709

int e = errno;

647

710

perror("write");

648

retval = -1;

711

errno = e;

649

712

goto mandos_end;

650

713

}

651

714

written += (size_t)ret;

659

722

break;

660

723

}

661

724

}

725

726

if(quit_now){

727

errno = EINTR;

728

goto mandos_end;

729

}

662

730

}

663

731

664

732

if(debug){

665

733

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

666

734

}

667

735

736

if(quit_now){

737

errno = EINTR;

738

goto mandos_end;

739

}

740

668

741

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

669

742

670

do{

743

if(quit_now){

744

errno = EINTR;

745

goto mandos_end;

746

}

747

748

do {

671

749

ret = gnutls_handshake(session);

750

if(quit_now){

751

errno = EINTR;

752

goto mandos_end;

753

}

672

754

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

673

755

674

756

if(ret != GNUTLS_E_SUCCESS){

676

758

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

677

759

gnutls_perror(ret);

678

760

}

679

retval = -1;

761

errno = EPROTO;

680

762

goto mandos_end;

681

763

}

682

764

688

770

}

689

771

690

772

while(true){

773

774

if(quit_now){

775

errno = EINTR;

776

goto mandos_end;

777

}

778

691

779

buffer_capacity = incbuffer(&buffer, buffer_length,

692

780

buffer_capacity);

693

781

if(buffer_capacity == 0){

782

int e = errno;

694

783

perror("incbuffer");

695

retval = -1;

784

errno = e;

785

goto mandos_end;

786

}

787

788

if(quit_now){

789

errno = EINTR;

696

790

goto mandos_end;

697

791

}

698

792

707

801

case GNUTLS_E_AGAIN:

708

802

break;

709

803

case GNUTLS_E_REHANDSHAKE:

710

do{

804

do {

711

805

ret = gnutls_handshake(session);

806

807

if(quit_now){

808

errno = EINTR;

809

goto mandos_end;

810

}

712

811

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

713

812

if(ret < 0){

714

813

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

715

814

gnutls_perror(ret);

716

retval = -1;

815

errno = EPROTO;

717

816

goto mandos_end;

718

817

}

719

818

break;

720

819

default:

721

820

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

722

821

" encrypted session with Mandos server\n");

723

retval = -1;

724

822

gnutls_bye(session, GNUTLS_SHUT_RDWR);

823

errno = EIO;

725

824

goto mandos_end;

726

825

}

727

826

} else {

733

832

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

734

833

}

735

834

736

gnutls_bye(session, GNUTLS_SHUT_RDWR);

835

if(quit_now){

836

errno = EINTR;

837

goto mandos_end;

838

}

839

840

do {

841

ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);

842

if(quit_now){

843

errno = EINTR;

844

goto mandos_end;

845

}

846

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

737

847

738

848

if(buffer_length > 0){

849

ssize_t decrypted_buffer_size;

739

850

decrypted_buffer_size = pgp_packet_decrypt(buffer,

740

851

buffer_length,

741

852

&decrypted_buffer);

742

853

if(decrypted_buffer_size >= 0){

854

743

855

written = 0;

744

856

while(written < (size_t) decrypted_buffer_size){

857

if(quit_now){

858

errno = EINTR;

859

goto mandos_end;

860

}

861

745

862

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

746

863

(size_t)decrypted_buffer_size - written,

747

864

stdout);

748

865

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

866

int e = errno;

749

867

if(debug){

750

868

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

751

869

strerror(errno));

752

870

}

753

retval = -1;

754

break;

871

errno = e;

872

goto mandos_end;

755

873

}

756

874

written += (size_t)ret;

757

875

}

758

free(decrypted_buffer);

759

} else {

760

retval = -1;

876

retval = 0;

761

877

}

762

} else {

763

retval = -1;

764

878

}

765

879

766

880

/* Shutdown procedure */

767

881

768

882

mandos_end:

769

free(buffer);

770

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

771

if(ret == -1){

772

perror("close");

883

{

884

int e = errno;

885

free(decrypted_buffer);

886

free(buffer);

887

if(tcp_sd >= 0){

888

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

889

}

890

if(ret == -1){

891

if(e == 0){

892

e = errno;

893

}

894

perror("close");

895

}

896

gnutls_deinit(session);

897

if(quit_now){

898

e = EINTR;

899

retval = -1;

900

}

901

errno = e;

773

902

}

774

gnutls_deinit(session);

775

903

return retval;

776

904

}

777

905

794

922

/* Called whenever a service has been resolved successfully or

795

923

timed out */

796

924

925

if(quit_now){

926

return;

927

}

928

797

929

switch(event){

798

930

default:

799

931

case AVAHI_RESOLVER_FAILURE:

836

968

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

837

969

is removed from the LAN */

838

970

971

if(quit_now){

972

return;

973

}

974

839

975

switch(event){

840

976

default:

841

977

case AVAHI_BROWSER_FAILURE:

851

987

the callback function is called the Avahi server will free the

852

988

resolver for us. */

853

989

854

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

855

protocol, name, type, domain,

856

AVAHI_PROTO_INET6, 0,

857

resolve_callback, NULL)))

990

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

991

name, type, domain, protocol, 0,

992

resolve_callback, NULL) == NULL)

858

993

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

859

994

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

860

995

break;

871

1006

}

872

1007

}

873

1008

874

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

1009

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

1010

static void handle_sigterm(int sig){

1011

if(quit_now){

1012

return;

1013

}

1014

quit_now = 1;

1015

signal_received = sig;

875

1016

int old_errno = errno;

876

avahi_simple_poll_quit(mc.simple_poll);

1017

if(mc.simple_poll != NULL){

1018

avahi_simple_poll_quit(mc.simple_poll);

1019

}

877

1020

errno = old_errno;

878

1021

}

879

1022

882

1025

int error;

883

1026

int ret;

884

1027

intmax_t tmpmax;

885

int numchars;

1028

char *tmp;

886

1029

int exitcode = EXIT_SUCCESS;

887

1030

const char *interface = "eth0";

888

1031

struct ifreq network;

889

int sd;

1032

int sd = -1;

1033

bool take_down_interface = false;

890

1034

uid_t uid;

891

1035

gid_t gid;

892

1036

char *connect_to = NULL;

896

1040

const char *seckey = PATHDIR "/" SECKEY;

897

1041

const char *pubkey = PATHDIR "/" PUBKEY;

898

1042

899

/* Initialize Mandos context */

900

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

901

.dh_bits = 1024, .priority = "SECURE256"

902

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

903

1043

bool gnutls_initialized = false;

904

1044

bool gpgme_initialized = false;

905

double delay = 2.5;

906

907

struct sigaction old_sigterm_action;

1045

float delay = 2.5f;

1046

1047

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

908

1048

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

909

1049

1050

uid = getuid();

1051

gid = getgid();

1052

1053

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

1054

errno = 0;

1055

ret = setgid(gid);

1056

if(ret == -1){

1057

perror("setgid");

1058

}

1059

1060

/* Lower user privileges (temporarily) */

1061

errno = 0;

1062

ret = seteuid(uid);

1063

if(ret == -1){

1064

perror("seteuid");

1065

}

1066

1067

if(quit_now){

1068

goto end;

1069

}

1070

910

1071

{

911

1072

struct argp_option options[] = {

912

1073

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

941

1102

.arg = "SECONDS",

942

1103

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

943

1104

.group = 2 },

1105

/*

1106

* These reproduce what we would get without ARGP_NO_HELP

1107

*/

1108

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

1109

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

1110

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

1111

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

1112

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

1113

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

944

1114

{ .name = NULL }

945

1115

};

946

1116

947

1117

error_t parse_opt(int key, char *arg,

948

1118

struct argp_state *state){

1119

errno = 0;

949

1120

switch(key){

950

1121

case 128: /* --debug */

951

1122

debug = true;

963

1134

pubkey = arg;

964

1135

break;

965

1136

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

966

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

967

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

968

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

969

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

970

exit(EXIT_FAILURE);

1137

errno = 0;

1138

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

1139

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

1140

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

1141

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

971

1142

}

972

1143

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

973

1144

break;

975

1146

mc.priority = arg;

976

1147

break;

977

1148

case 131: /* --delay */

978

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

979

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

980

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

981

exit(EXIT_FAILURE);

1149

errno = 0;

1150

delay = strtof(arg, &tmp);

1151

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

1152

argp_error(state, "Bad delay");

982

1153

}

983

1154

break;

984

case ARGP_KEY_ARG:

985

argp_usage(state);

986

case ARGP_KEY_END:

1155

/*

1156

* These reproduce what we would get without ARGP_NO_HELP

1157

*/

1158

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

1159

argp_state_help(state, state->out_stream,

1160

(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)

1161

& ~(unsigned int)ARGP_HELP_EXIT_OK);

1162

case -3: /* --usage */

1163

argp_state_help(state, state->out_stream,

1164

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1165

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

1166

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

1167

exit(argp_err_exit_status);

987

1168

break;

988

1169

default:

989

1170

return ARGP_ERR_UNKNOWN;

990

1171

}

991

return 0;

1172

return errno;

992

1173

}

993

1174

994

1175

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

995

1176

.args_doc = "",

996

1177

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

997

1178

" passwords from a Mandos server" };

998

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

999

if(ret == ARGP_ERR_UNKNOWN){

1000

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

1001

exitcode = EXIT_FAILURE;

1179

ret = argp_parse(&argp, argc, argv,

1180

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1181

switch(ret){

1182

case 0:

1183

break;

1184

case ENOMEM:

1185

default:

1186

errno = ret;

1187

perror("argp_parse");

1188

exitcode = EX_OSERR;

1189

goto end;

1190

case EINVAL:

1191

exitcode = EX_USAGE;

1192

goto end;

1193

}

1194

}

1195

1196

if(not debug){

1197

avahi_set_log_function(empty_log);

1198

}

1199

1200

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

1201

from the signal handler */

1202

/* Initialize the pseudo-RNG for Avahi */

1203

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

1204

mc.simple_poll = avahi_simple_poll_new();

1205

if(mc.simple_poll == NULL){

1206

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

1207

exitcode = EX_UNAVAILABLE;

1208

goto end;

1209

}

1210

1211

sigemptyset(&sigterm_action.sa_mask);

1212

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

1213

if(ret == -1){

1214

perror("sigaddset");

1215

exitcode = EX_OSERR;

1216

goto end;

1217

}

1218

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

1219

if(ret == -1){

1220

perror("sigaddset");

1221

exitcode = EX_OSERR;

1222

goto end;

1223

}

1224

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

1225

if(ret == -1){

1226

perror("sigaddset");

1227

exitcode = EX_OSERR;

1228

goto end;

1229

}

1230

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

1231

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

1232

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

1233

*/

1234

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

1235

if(ret == -1){

1236

perror("sigaction");

1237

return EX_OSERR;

1238

}

1239

if(old_sigterm_action.sa_handler != SIG_IGN){

1240

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

1241

if(ret == -1){

1242

perror("sigaction");

1243

exitcode = EX_OSERR;

1244

goto end;

1245

}

1246

}

1247

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

1248

if(ret == -1){

1249

perror("sigaction");

1250

return EX_OSERR;

1251

}

1252

if(old_sigterm_action.sa_handler != SIG_IGN){

1253

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

1254

if(ret == -1){

1255

perror("sigaction");

1256

exitcode = EX_OSERR;

1257

goto end;

1258

}

1259

}

1260

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

1261

if(ret == -1){

1262

perror("sigaction");

1263

return EX_OSERR;

1264

}

1265

if(old_sigterm_action.sa_handler != SIG_IGN){

1266

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

1267

if(ret == -1){

1268

perror("sigaction");

1269

exitcode = EX_OSERR;

1002

1270

goto end;

1003

1271

}

1004

1272

}

1005

1273

1006

1274

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

1007

1275

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

1276

if_index = (AvahiIfIndex) if_nametoindex(interface);

1277

if(if_index == 0){

1278

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

1279

exitcode = EX_UNAVAILABLE;

1280

goto end;

1281

}

1282

1283

if(quit_now){

1284

goto end;

1285

}

1286

1287

/* Re-raise priviliges */

1288

errno = 0;

1289

ret = seteuid(0);

1290

if(ret == -1){

1291

perror("seteuid");

1292

}

1293

1008

1294

#ifdef __linux__

1009

1295

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1010

messages to mess up the prompt */

1296

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

1011

1297

ret = klogctl(8, NULL, 5);

1012

1298

bool restore_loglevel = true;

1013

1299

if(ret == -1){

1014

1300

restore_loglevel = false;

1015

1301

perror("klogctl");

1016

1302

}

1017

#endif

1303

#endif /* __linux__ */

1018

1304

1019

1305

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1020

1306

if(sd < 0){

1021

1307

perror("socket");

1022

exitcode = EXIT_FAILURE;

1308

exitcode = EX_OSERR;

1023

1309

#ifdef __linux__

1024

1310

if(restore_loglevel){

1025

1311

ret = klogctl(7, NULL, 0);

1027

1313

perror("klogctl");

1028

1314

}

1029

1315

}

1030

#endif

1316

#endif /* __linux__ */

1317

/* Lower privileges */

1318

errno = 0;

1319

ret = seteuid(uid);

1320

if(ret == -1){

1321

perror("seteuid");

1322

}

1031

1323

goto end;

1032

1324

}

1033

1325

strcpy(network.ifr_name, interface);

1041

1333

perror("klogctl");

1042

1334

}

1043

1335

}

1044

#endif

1045

exitcode = EXIT_FAILURE;

1336

#endif /* __linux__ */

1337

exitcode = EX_OSERR;

1338

/* Lower privileges */

1339

errno = 0;

1340

ret = seteuid(uid);

1341

if(ret == -1){

1342

perror("seteuid");

1343

}

1046

1344

goto end;

1047

1345

}

1048

1346

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

1049

1347

network.ifr_flags |= IFF_UP;

1348

take_down_interface = true;

1050

1349

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

1051

1350

if(ret == -1){

1351

take_down_interface = false;

1052

1352

perror("ioctl SIOCSIFFLAGS");

1053

exitcode = EXIT_FAILURE;

1353

exitcode = EX_OSERR;

1054

1354

#ifdef __linux__

1055

1355

if(restore_loglevel){

1056

1356

ret = klogctl(7, NULL, 0);

1058

1358

perror("klogctl");

1059

1359

}

1060

1360

}

1061

#endif

1361

#endif /* __linux__ */

1362

/* Lower privileges */

1363

errno = 0;

1364

ret = seteuid(uid);

1365

if(ret == -1){

1366

perror("seteuid");

1367

}

1062

1368

goto end;

1063

1369

}

1064

1370

}

1076

1382

perror("nanosleep");

1077

1383

}

1078

1384

}

1079

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

1080

if(ret == -1){

1081

perror("close");

1385

if(not take_down_interface){

1386

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

1387

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

1388

if(ret == -1){

1389

perror("close");

1390

}

1082

1391

}

1083

1392

#ifdef __linux__

1084

1393

if(restore_loglevel){

1088

1397

perror("klogctl");

1089

1398

}

1090

1399

}

1091

#endif

1092

}

1093

1094

uid = getuid();

1095

gid = getgid();

1096

1097

errno = 0;

1098

setgid(gid);

1099

if(ret == -1){

1100

perror("setgid");

1101

}

1102

1103

ret = setuid(uid);

1104

if(ret == -1){

1105

perror("setuid");

1400

#endif /* __linux__ */

1401

/* Lower privileges */

1402

errno = 0;

1403

if(take_down_interface){

1404

/* Lower privileges */

1405

ret = seteuid(uid);

1406

if(ret == -1){

1407

perror("seteuid");

1408

}

1409

} else {

1410

/* Lower privileges permanently */

1411

ret = setuid(uid);

1412

if(ret == -1){

1413

perror("setuid");

1414

}

1415

}

1416

}

1417

1418

if(quit_now){

1419

goto end;

1106

1420

}

1107

1421

1108

1422

ret = init_gnutls_global(pubkey, seckey);

1109

1423

if(ret == -1){

1110

1424

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

1111

exitcode = EXIT_FAILURE;

1425

exitcode = EX_UNAVAILABLE;

1112

1426

goto end;

1113

1427

} else {

1114

1428

gnutls_initialized = true;

1115

1429

}

1116

1430

1431

if(quit_now){

1432

goto end;

1433

}

1434

1435

tempdir_created = true;

1117

1436

if(mkdtemp(tempdir) == NULL){

1437

tempdir_created = false;

1118

1438

perror("mkdtemp");

1119

1439

goto end;

1120

1440

}

1121

tempdir_created = true;

1441

1442

if(quit_now){

1443

goto end;

1444

}

1122

1445

1123

1446

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

1124

1447

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

1125

exitcode = EXIT_FAILURE;

1448

exitcode = EX_UNAVAILABLE;

1126

1449

goto end;

1127

1450

} else {

1128

1451

gpgme_initialized = true;

1129

1452

}

1130

1453

1131

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

1132

if_index = (AvahiIfIndex) if_nametoindex(interface);

1133

if(if_index == 0){

1134

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

1135

exitcode = EXIT_FAILURE;

1136

goto end;

1137

}

1454

if(quit_now){

1455

goto end;

1138

1456

}

1139

1457

1140

1458

if(connect_to != NULL){

1143

1461

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

1144

1462

if(address == NULL){

1145

1463

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

1146

exitcode = EXIT_FAILURE;

1147

goto end;

1148

}

1464

exitcode = EX_USAGE;

1465

goto end;

1466

}

1467

1468

if(quit_now){

1469

goto end;

1470

}

1471

1149

1472

uint16_t port;

1150

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

1151

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

1152

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

1473

errno = 0;

1474

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

1475

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

1476

or tmpmax != (uint16_t)tmpmax){

1153

1477

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

1154

exitcode = EXIT_FAILURE;

1155

goto end;

1156

}

1478

exitcode = EX_USAGE;

1479

goto end;

1480

}

1481

1482

if(quit_now){

1483

goto end;

1484

}

1485

1157

1486

port = (uint16_t)tmpmax;

1158

1487

*address = '\0';

1159

1488

address = connect_to;

1164

1493

} else {

1165

1494

af = AF_INET;

1166

1495

}

1496

1497

if(quit_now){

1498

goto end;

1499

}

1500

1167

1501

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

1168

1502

if(ret < 0){

1169

exitcode = EXIT_FAILURE;

1503

switch(errno){

1504

case ENETUNREACH:

1505

case EHOSTDOWN:

1506

case EHOSTUNREACH:

1507

exitcode = EX_NOHOST;

1508

break;

1509

case EINVAL:

1510

exitcode = EX_USAGE;

1511

break;

1512

case EIO:

1513

exitcode = EX_IOERR;

1514

break;

1515

case EPROTO:

1516

exitcode = EX_PROTOCOL;

1517

break;

1518

default:

1519

exitcode = EX_OSERR;

1520

break;

1521

}

1170

1522

} else {

1171

1523

exitcode = EXIT_SUCCESS;

1172

1524

}

1173

1525

goto end;

1174

1526

}

1175

1527

1176

if(not debug){

1177

avahi_set_log_function(empty_log);

1178

}

1179

1180

/* Initialize the pseudo-RNG for Avahi */

1181

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

1182

1183

/* Allocate main Avahi loop object */

1184

mc.simple_poll = avahi_simple_poll_new();

1185

if(mc.simple_poll == NULL){

1186

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

1187

exitcode = EXIT_FAILURE;

1528

if(quit_now){

1188

1529

goto end;

1189

1530

}

1190

1531

1210

1551

if(mc.server == NULL){

1211

1552

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

1212

1553

avahi_strerror(error));

1213

exitcode = EXIT_FAILURE;

1554

exitcode = EX_UNAVAILABLE;

1555

goto end;

1556

}

1557

1558

if(quit_now){

1214

1559

goto end;

1215

1560

}

1216

1561

1217

1562

/* Create the Avahi service browser */

1218

1563

sb = avahi_s_service_browser_new(mc.server, if_index,

1219

AVAHI_PROTO_INET6, "_mandos._tcp",

1564

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

1220

1565

NULL, 0, browse_callback, NULL);

1221

1566

if(sb == NULL){

1222

1567

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

1223

1568

avahi_strerror(avahi_server_errno(mc.server)));

1224

exitcode = EXIT_FAILURE;

1569

exitcode = EX_UNAVAILABLE;

1225

1570

goto end;

1226

1571

}

1227

1572

1228

sigemptyset(&sigterm_action.sa_mask);

1229

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

1230

if(ret == -1){

1231

perror("sigaddset");

1232

exitcode = EXIT_FAILURE;

1573

if(quit_now){

1233

1574

goto end;

1234

1575

}

1235

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

1236

if(ret == -1){

1237

perror("sigaction");

1238

exitcode = EXIT_FAILURE;

1239

goto end;

1240

}

1241

1576

1242

1577

/* Run the main loop */

1243

1578

1273

1608

gpgme_release(mc.ctx);

1274

1609

}

1275

1610

1611

/* Take down the network interface */

1612

if(take_down_interface){

1613

/* Re-raise priviliges */

1614

errno = 0;

1615

ret = seteuid(0);

1616

if(ret == -1){

1617

perror("seteuid");

1618

}

1619

if(geteuid() == 0){

1620

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

1621

if(ret == -1){

1622

perror("ioctl SIOCGIFFLAGS");

1623

} else if(network.ifr_flags & IFF_UP) {

1624

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

1625

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

1626

if(ret == -1){

1627

perror("ioctl SIOCSIFFLAGS");

1628

}

1629

}

1630

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

1631

if(ret == -1){

1632

perror("close");

1633

}

1634

/* Lower privileges permanently */

1635

errno = 0;

1636

ret = setuid(uid);

1637

if(ret == -1){

1638

perror("setuid");

1639

}

1640

}

1641

}

1642

1276

1643

/* Removes the temp directory used by GPGME */

1277

1644

if(tempdir_created){

1278

1645

DIR *d;

1317

1684

}

1318

1685

}

1319

1686

1687

if(quit_now){

1688

sigemptyset(&old_sigterm_action.sa_mask);

1689

old_sigterm_action.sa_handler = SIG_DFL;

1690

ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,

1691

&old_sigterm_action,

1692

NULL));

1693

if(ret == -1){

1694

perror("sigaction");

1695

}

1696

do {

1697

ret = raise(signal_received);

1698

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

1699

if(ret != 0){

1700

perror("raise");

1701

abort();

1702

}

1703

TEMP_FAILURE_RETRY(pause());

1704

}

1705

1320

1706

return exitcode;

1321

1707

}