/mandos/trunk : revision 481

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

43

stdout, ferror(), remove() */

44

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

45

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

46

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

47

srand(), strtof() */

46

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

47

strtof(), abort() */

48

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

49

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

50

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

63

strtoimax() */

64

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

65

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

66

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

66

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

67

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

68

SIOCSIFFLAGS, if_indextoname(),

69

if_nametoindex(), IF_NAMESIZE */

71

INET_ADDRSTRLEN, INET6_ADDRSTRLEN

72

*/

73

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

74

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

75

setgid() */

74

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

75

setgid(), pause() */

76

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

77

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

78

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

82

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

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 */

85

87

86

88

#ifdef __linux__

87

89

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

125

127

static const char mandos_protocol_version[] = "1";

126

128

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

127

129

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

130

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

131

char *connect_to = NULL;

128

132

129

133

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

130

134

typedef struct {

142

146

.dh_bits = 1024, .priority = "SECURE256"

143

147

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

144

148

149

sig_atomic_t quit_now = 0;

150

int signal_received = 0;

151

145

152

/*

146

153

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

147

154

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

164

171

*/

165

172

static bool init_gpgme(const char *seckey,

166

173

const char *pubkey, const char *tempdir){

167

int ret;

168

174

gpgme_error_t rc;

169

175

gpgme_engine_info_t engine_info;

170

176

173

179

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

174

180

*/

175

181

bool import_key(const char *filename){

182

int ret;

176

183

int fd;

177

184

gpgme_data_t pgp_data;

178

185

474

481

static int init_gnutls_session(gnutls_session_t *session){

475

482

int ret;

476

483

/* GnuTLS session creation */

477

ret = gnutls_init(session, GNUTLS_SERVER);

484

do {

485

ret = gnutls_init(session, GNUTLS_SERVER);

486

if(quit_now){

487

return -1;

488

}

489

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

478

490

if(ret != GNUTLS_E_SUCCESS){

479

491

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

480

492

safer_gnutls_strerror(ret));

482

494

483

495

{

484

496

const char *err;

485

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

497

do {

498

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

499

if(quit_now){

500

gnutls_deinit(*session);

501

return -1;

502

}

503

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

486

504

if(ret != GNUTLS_E_SUCCESS){

487

505

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

488

506

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

492

510

}

493

511

}

494

512

495

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

496

mc.cred);

513

do {

514

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

515

mc.cred);

516

if(quit_now){

517

gnutls_deinit(*session);

518

return -1;

519

}

520

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

497

521

if(ret != GNUTLS_E_SUCCESS){

498

522

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

499

523

safer_gnutls_strerror(ret));

502

526

}

503

527

504

528

/* ignore client certificate if any. */

505

gnutls_certificate_server_set_request(*session,

506

GNUTLS_CERT_IGNORE);

529

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

507

530

508

531

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

509

532

514

537

static void empty_log(__attribute__((unused)) AvahiLogLevel level,

515

538

__attribute__((unused)) const char *txt){}

516

539

517

sig_atomic_t quit_now = 0;

518

int signal_received = 0;

519

520

540

/* Called when a Mandos server is found */

521

541

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

522

542

AvahiIfIndex if_index,

523

543

int af){

524

int ret, tcp_sd;

544

int ret, tcp_sd = -1;

525

545

ssize_t sret;

526

546

union {

527

547

struct sockaddr_in in;

528

548

struct sockaddr_in6 in6;

529

549

} to;

530

550

char *buffer = NULL;

531

char *decrypted_buffer;

551

char *decrypted_buffer = NULL;

532

552

size_t buffer_length = 0;

533

553

size_t buffer_capacity = 0;

534

ssize_t decrypted_buffer_size;

535

554

size_t written;

536

int retval = 0;

555

int retval = -1;

537

556

gnutls_session_t session;

538

557

int pf; /* Protocol family */

539

558

559

errno = 0;

560

561

if(quit_now){

562

errno = EINTR;

563

return -1;

564

}

565

540

566

switch(af){

541

567

case AF_INET6:

542

568

pf = PF_INET6;

546

572

break;

547

573

default:

548

574

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

575

errno = EINVAL;

549

576

return -1;

550

577

}

551

578

561

588

562

589

tcp_sd = socket(pf, SOCK_STREAM, 0);

563

590

if(tcp_sd < 0){

591

int e = errno;

564

592

perror("socket");

565

return -1;

593

errno = e;

594

goto mandos_end;

595

}

596

597

if(quit_now){

598

errno = EINTR;

599

goto mandos_end;

566

600

}

567

601

568

602

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

574

608

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

575

609

}

576

610

if(ret < 0 ){

611

int e = errno;

577

612

perror("inet_pton");

578

return -1;

613

errno = e;

614

goto mandos_end;

579

615

}

580

616

if(ret == 0){

617

int e = errno;

581

618

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

582

return -1;

619

errno = e;

620

goto mandos_end;

583

621

}

584

622

if(af == AF_INET6){

585

623

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

592

630

if(if_index == AVAHI_IF_UNSPEC){

593

631

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

594

632

" without a network interface\n");

595

return -1;

633

errno = EINVAL;

634

goto mandos_end;

596

635

}

597

636

/* Set the network interface number as scope */

598

637

to.in6.sin6_scope_id = (uint32_t)if_index;

603

642

-Wunreachable-code */

604

643

}

605

644

645

if(quit_now){

646

errno = EINTR;

647

goto mandos_end;

648

}

649

606

650

if(debug){

607

651

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

608

652

char interface[IF_NAMESIZE];

635

679

}

636

680

}

637

681

682

if(quit_now){

683

errno = EINTR;

684

goto mandos_end;

685

}

686

638

687

if(af == AF_INET6){

639

688

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

640

689

} else {

641

690

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

642

691

}

643

692

if(ret < 0){

644

perror("connect");

645

return -1;

693

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

694

int e = errno;

695

perror("connect");

696

errno = e;

697

}

698

goto mandos_end;

699

}

700

701

if(quit_now){

702

errno = EINTR;

703

goto mandos_end;

646

704

}

647

705

648

706

const char *out = mandos_protocol_version;

652

710

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

653

711

out_size - written));

654

712

if(ret == -1){

713

int e = errno;

655

714

perror("write");

656

retval = -1;

715

errno = e;

657

716

goto mandos_end;

658

717

}

659

718

written += (size_t)ret;

667

726

break;

668

727

}

669

728

}

729

730

if(quit_now){

731

errno = EINTR;

732

goto mandos_end;

733

}

670

734

}

671

735

672

736

if(debug){

673

737

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

674

738

}

675

739

740

if(quit_now){

741

errno = EINTR;

742

goto mandos_end;

743

}

744

676

745

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

677

746

678

do{

747

if(quit_now){

748

errno = EINTR;

749

goto mandos_end;

750

}

751

752

do {

679

753

ret = gnutls_handshake(session);

754

if(quit_now){

755

errno = EINTR;

756

goto mandos_end;

757

}

680

758

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

681

759

682

760

if(ret != GNUTLS_E_SUCCESS){

684

762

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

685

763

gnutls_perror(ret);

686

764

}

687

retval = -1;

765

errno = EPROTO;

688

766

goto mandos_end;

689

767

}

690

768

696

774

}

697

775

698

776

while(true){

777

778

if(quit_now){

779

errno = EINTR;

780

goto mandos_end;

781

}

782

699

783

buffer_capacity = incbuffer(&buffer, buffer_length,

700

784

buffer_capacity);

701

785

if(buffer_capacity == 0){

786

int e = errno;

702

787

perror("incbuffer");

703

retval = -1;

788

errno = e;

789

goto mandos_end;

790

}

791

792

if(quit_now){

793

errno = EINTR;

704

794

goto mandos_end;

705

795

}

706

796

715

805

case GNUTLS_E_AGAIN:

716

806

break;

717

807

case GNUTLS_E_REHANDSHAKE:

718

do{

808

do {

719

809

ret = gnutls_handshake(session);

810

811

if(quit_now){

812

errno = EINTR;

813

goto mandos_end;

814

}

720

815

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

721

816

if(ret < 0){

722

817

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

723

818

gnutls_perror(ret);

724

retval = -1;

819

errno = EPROTO;

725

820

goto mandos_end;

726

821

}

727

822

break;

728

823

default:

729

824

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

730

825

" encrypted session with Mandos server\n");

731

retval = -1;

732

826

gnutls_bye(session, GNUTLS_SHUT_RDWR);

827

errno = EIO;

733

828

goto mandos_end;

734

829

}

735

830

} else {

741

836

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

742

837

}

743

838

744

gnutls_bye(session, GNUTLS_SHUT_RDWR);

839

if(quit_now){

840

errno = EINTR;

841

goto mandos_end;

842

}

843

844

do {

845

ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);

846

if(quit_now){

847

errno = EINTR;

848

goto mandos_end;

849

}

850

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

745

851

746

852

if(buffer_length > 0){

853

ssize_t decrypted_buffer_size;

747

854

decrypted_buffer_size = pgp_packet_decrypt(buffer,

748

855

buffer_length,

749

856

&decrypted_buffer);

750

857

if(decrypted_buffer_size >= 0){

858

751

859

written = 0;

752

860

while(written < (size_t) decrypted_buffer_size){

861

if(quit_now){

862

errno = EINTR;

863

goto mandos_end;

864

}

865

753

866

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

754

867

(size_t)decrypted_buffer_size - written,

755

868

stdout);

756

869

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

870

int e = errno;

757

871

if(debug){

758

872

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

759

873

strerror(errno));

760

874

}

761

retval = -1;

762

break;

875

errno = e;

876

goto mandos_end;

763

877

}

764

878

written += (size_t)ret;

765

879

}

766

free(decrypted_buffer);

767

} else {

768

retval = -1;

880

retval = 0;

769

881

}

770

} else {

771

retval = -1;

772

882

}

773

883

774

884

/* Shutdown procedure */

775

885

776

886

mandos_end:

777

free(buffer);

778

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

779

if(ret == -1){

780

perror("close");

887

{

888

int e = errno;

889

free(decrypted_buffer);

890

free(buffer);

891

if(tcp_sd >= 0){

892

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

893

}

894

if(ret == -1){

895

if(e == 0){

896

e = errno;

897

}

898

perror("close");

899

}

900

gnutls_deinit(session);

901

if(quit_now){

902

e = EINTR;

903

retval = -1;

904

}

905

errno = e;

781

906

}

782

gnutls_deinit(session);

783

907

return retval;

784

908

}

785

909

848

972

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

849

973

is removed from the LAN */

850

974

975

if(quit_now){

976

return;

977

}

978

851

979

switch(event){

852

980

default:

853

981

case AVAHI_BROWSER_FAILURE:

896

1024

errno = old_errno;

897

1025

}

898

1026

1027

/*

1028

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

1029

* corresponds to an acceptable network device.

1030

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

1031

*/

1032

int good_interface(const struct dirent *if_entry){

1033

ssize_t ssret;

1034

char *flagname = NULL;

1035

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

1036

return 0;

1037

}

1038

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

1039

if_entry->d_name);

1040

if(ret < 0){

1041

perror("asprintf");

1042

return 0;

1043

}

1044

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

1045

if(flags_fd == -1){

1046

perror("open");

1047

free(flagname);

1048

return 0;

1049

}

1050

free(flagname);

1051

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

1052

/* read line from flags_fd */

1053

ssize_t to_read = (sizeof(ifreq_flags)*2)+3; /* "0x1003\n" */

1054

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

1055

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

1056

if(flagstring == NULL){

1057

perror("malloc");

1058

close(flags_fd);

1059

return 0;

1060

}

1061

while(to_read > 0){

1062

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

1063

(size_t)to_read));

1064

if(ssret == -1){

1065

perror("read");

1066

free(flagstring);

1067

close(flags_fd);

1068

return 0;

1069

}

1070

to_read -= ssret;

1071

if(ssret == 0){

1072

break;

1073

}

1074

}

1075

close(flags_fd);

1076

intmax_t tmpmax;

1077

char *tmp;

1078

errno = 0;

1079

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

1080

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

1081

and not (isspace(*tmp)))

1082

or tmpmax != (ifreq_flags)tmpmax){

1083

if(debug){

1084

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

1085

flagstring, if_entry->d_name);

1086

}

1087

free(flagstring);

1088

return 0;

1089

}

1090

free(flagstring);

1091

ifreq_flags flags = (ifreq_flags)tmpmax;

1092

/* Reject the loopback device */

1093

if(flags & IFF_LOOPBACK){

1094

if(debug){

1095

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

1096

if_entry->d_name);

1097

}

1098

return 0;

1099

}

1100

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

1101

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

1102

if(debug){

1103

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

1104

if_entry->d_name);

1105

}

1106

return 1;

1107

}

1108

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

1109

if(not (flags & IFF_BROADCAST)){

1110

if(debug){

1111

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

1112

if_entry->d_name);

1113

}

1114

return 0;

1115

}

1116

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

1117

if(flags & IFF_NOARP){

1118

if(debug){

1119

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

1120

if_entry->d_name);

1121

}

1122

return 0;

1123

}

1124

/* Accept this device */

1125

if(debug){

1126

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

1127

if_entry->d_name);

1128

}

1129

return 1;

1130

}

1131

899

1132

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

900

1133

AvahiSServiceBrowser *sb = NULL;

901

1134

int error;

903

1136

intmax_t tmpmax;

904

1137

char *tmp;

905

1138

int exitcode = EXIT_SUCCESS;

906

const char *interface = "eth0";

1139

const char *interface = "";

907

1140

struct ifreq network;

908

1141

int sd = -1;

909

1142

bool take_down_interface = false;

910

1143

uid_t uid;

911

1144

gid_t gid;

912

char *connect_to = NULL;

913

1145

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

914

1146

bool tempdir_created = false;

915

1147

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

920

1152

bool gpgme_initialized = false;

921

1153

float delay = 2.5f;

922

1154

923

struct sigaction old_sigterm_action;

1155

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

924

1156

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

925

1157

1158

uid = getuid();

1159

gid = getgid();

1160

1161

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

1162

errno = 0;

1163

ret = setgid(gid);

1164

if(ret == -1){

1165

perror("setgid");

1166

}

1167

1168

/* Lower user privileges (temporarily) */

1169

errno = 0;

1170

ret = seteuid(uid);

1171

if(ret == -1){

1172

perror("seteuid");

1173

}

1174

1175

if(quit_now){

1176

goto end;

1177

}

1178

926

1179

{

927

1180

struct argp_option options[] = {

928

1181

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

957

1210

.arg = "SECONDS",

958

1211

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

959

1212

.group = 2 },

1213

/*

1214

* These reproduce what we would get without ARGP_NO_HELP

1215

*/

1216

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

1217

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

1218

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

1219

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

1220

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

1221

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

960

1222

{ .name = NULL }

961

1223

};

962

1224

963

1225

error_t parse_opt(int key, char *arg,

964

1226

struct argp_state *state){

1227

errno = 0;

965

1228

switch(key){

966

1229

case 128: /* --debug */

967

1230

debug = true;

983

1246

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

984

1247

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

985

1248

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

986

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

987

exit(EXIT_FAILURE);

1249

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

988

1250

}

989

1251

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

990

1252

break;

995

1257

errno = 0;

996

1258

delay = strtof(arg, &tmp);

997

1259

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

998

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

999

exit(EXIT_FAILURE);

1260

argp_error(state, "Bad delay");

1000

1261

}

1001

1262

break;

1002

case ARGP_KEY_ARG:

1003

argp_usage(state);

1004

case ARGP_KEY_END:

1263

/*

1264

* These reproduce what we would get without ARGP_NO_HELP

1265

*/

1266

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

1267

argp_state_help(state, state->out_stream,

1268

(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)

1269

& ~(unsigned int)ARGP_HELP_EXIT_OK);

1270

case -3: /* --usage */

1271

argp_state_help(state, state->out_stream,

1272

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1273

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

1274

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

1275

exit(argp_err_exit_status);

1005

1276

break;

1006

1277

default:

1007

1278

return ARGP_ERR_UNKNOWN;

1008

1279

}

1009

return 0;

1280

return errno;

1010

1281

}

1011

1282

1012

1283

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

1013

1284

.args_doc = "",

1014

1285

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

1015

1286

" passwords from a Mandos server" };

1016

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

1017

if(ret == ARGP_ERR_UNKNOWN){

1018

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

1019

exitcode = EXIT_FAILURE;

1287

ret = argp_parse(&argp, argc, argv,

1288

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1289

switch(ret){

1290

case 0:

1291

break;

1292

case ENOMEM:

1293

default:

1294

errno = ret;

1295

perror("argp_parse");

1296

exitcode = EX_OSERR;

1297

goto end;

1298

case EINVAL:

1299

exitcode = EX_USAGE;

1020

1300

goto end;

1021

1301

}

1022

1302

}

1024

1304

if(not debug){

1025

1305

avahi_set_log_function(empty_log);

1026

1306

}

1307

1308

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

1309

struct dirent **direntries;

1310

ret = scandir(sys_class_net, &direntries, good_interface,

1311

alphasort);

1312

if(ret >= 1){

1313

/* Pick the first good interface */

1314

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

1315

if(debug){

1316

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

1317

}

1318

if(interface == NULL){

1319

perror("malloc");

1320

free(direntries);

1321

exitcode = EXIT_FAILURE;

1322

goto end;

1323

}

1324

free(direntries);

1325

} else {

1326

free(direntries);

1327

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

1328

exitcode = EXIT_FAILURE;

1329

goto end;

1330

}

1331

}

1027

1332

1028

1333

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

1029

1334

from the signal handler */

1032

1337

mc.simple_poll = avahi_simple_poll_new();

1033

1338

if(mc.simple_poll == NULL){

1034

1339

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

1035

exitcode = EXIT_FAILURE;

1340

exitcode = EX_UNAVAILABLE;

1036

1341

goto end;

1037

1342

}

1038

1343

1040

1345

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

1041

1346

if(ret == -1){

1042

1347

perror("sigaddset");

1043

exitcode = EXIT_FAILURE;

1348

exitcode = EX_OSERR;

1044

1349

goto end;

1045

1350

}

1046

1351

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

1047

1352

if(ret == -1){

1048

1353

perror("sigaddset");

1049

exitcode = EXIT_FAILURE;

1354

exitcode = EX_OSERR;

1050

1355

goto end;

1051

1356

}

1052

1357

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

1053

1358

if(ret == -1){

1054

1359

perror("sigaddset");

1055

exitcode = EXIT_FAILURE;

1056

goto end;

1057

}

1058

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

1059

if(ret == -1){

1060

perror("sigaction");

1061

exitcode = EXIT_FAILURE;

1062

goto end;

1063

}

1064

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

1065

if(ret == -1){

1066

perror("sigaction");

1067

exitcode = EXIT_FAILURE;

1068

goto end;

1069

}

1070

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

1071

if(ret == -1){

1072

perror("sigaction");

1073

exitcode = EXIT_FAILURE;

1074

goto end;

1360

exitcode = EX_OSERR;

1361

goto end;

1362

}

1363

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

1364

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

1365

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

1366

*/

1367

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

1368

if(ret == -1){

1369

perror("sigaction");

1370

return EX_OSERR;

1371

}

1372

if(old_sigterm_action.sa_handler != SIG_IGN){

1373

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

1374

if(ret == -1){

1375

perror("sigaction");

1376

exitcode = EX_OSERR;

1377

goto end;

1378

}

1379

}

1380

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

1381

if(ret == -1){

1382

perror("sigaction");

1383

return EX_OSERR;

1384

}

1385

if(old_sigterm_action.sa_handler != SIG_IGN){

1386

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

1387

if(ret == -1){

1388

perror("sigaction");

1389

exitcode = EX_OSERR;

1390

goto end;

1391

}

1392

}

1393

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

1394

if(ret == -1){

1395

perror("sigaction");

1396

return EX_OSERR;

1397

}

1398

if(old_sigterm_action.sa_handler != SIG_IGN){

1399

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

1400

if(ret == -1){

1401

perror("sigaction");

1402

exitcode = EX_OSERR;

1403

goto end;

1404

}

1075

1405

}

1076

1406

1077

1407

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

1078

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

1408

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

1079

1409

if_index = (AvahiIfIndex) if_nametoindex(interface);

1080

1410

if(if_index == 0){

1081

1411

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

1082

exitcode = EXIT_FAILURE;

1412

exitcode = EX_UNAVAILABLE;

1083

1413

goto end;

1084

1414

}

1085

1415

1087

1417

goto end;

1088

1418

}

1089

1419

1420

/* Re-raise priviliges */

1421

errno = 0;

1422

ret = seteuid(0);

1423

if(ret == -1){

1424

perror("seteuid");

1425

}

1426

1090

1427

#ifdef __linux__

1091

1428

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1092

messages to mess up the prompt */

1429

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

1093

1430

ret = klogctl(8, NULL, 5);

1094

1431

bool restore_loglevel = true;

1095

1432

if(ret == -1){

1101

1438

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1102

1439

if(sd < 0){

1103

1440

perror("socket");

1104

exitcode = EXIT_FAILURE;

1441

exitcode = EX_OSERR;

1105

1442

#ifdef __linux__

1106

1443

if(restore_loglevel){

1107

1444

ret = klogctl(7, NULL, 0);

1110

1447

}

1111

1448

}

1112

1449

#endif /* __linux__ */

1450

/* Lower privileges */

1451

errno = 0;

1452

ret = seteuid(uid);

1453

if(ret == -1){

1454

perror("seteuid");

1455

}

1113

1456

goto end;

1114

1457

}

1115

1458

strcpy(network.ifr_name, interface);

1124

1467

}

1125

1468

}

1126

1469

#endif /* __linux__ */

1127

exitcode = EXIT_FAILURE;

1470

exitcode = EX_OSERR;

1471

/* Lower privileges */

1472

errno = 0;

1473

ret = seteuid(uid);

1474

if(ret == -1){

1475

perror("seteuid");

1476

}

1128

1477

goto end;

1129

1478

}

1130

1479

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

1133

1482

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

1134

1483

if(ret == -1){

1135

1484

take_down_interface = false;

1136

perror("ioctl SIOCSIFFLAGS");

1137

exitcode = EXIT_FAILURE;

1485

perror("ioctl SIOCSIFFLAGS +IFF_UP");

1486

exitcode = EX_OSERR;

1138

1487

#ifdef __linux__

1139

1488

if(restore_loglevel){

1140

1489

ret = klogctl(7, NULL, 0);

1143

1492

}

1144

1493

}

1145

1494

#endif /* __linux__ */

1495

/* Lower privileges */

1496

errno = 0;

1497

ret = seteuid(uid);

1498

if(ret == -1){

1499

perror("seteuid");

1500

}

1146

1501

goto end;

1147

1502

}

1148

1503

}

1176

1531

}

1177

1532

}

1178

1533

#endif /* __linux__ */

1179

}

1180

1181

if(quit_now){

1182

goto end;

1183

}

1184

1185

uid = getuid();

1186

gid = getgid();

1187

1188

errno = 0;

1189

setgid(gid);

1190

if(ret == -1){

1191

perror("setgid");

1192

}

1193

1194

ret = setuid(uid);

1195

if(ret == -1){

1196

perror("setuid");

1534

/* Lower privileges */

1535

errno = 0;

1536

if(take_down_interface){

1537

/* Lower privileges */

1538

ret = seteuid(uid);

1539

if(ret == -1){

1540

perror("seteuid");

1541

}

1542

} else {

1543

/* Lower privileges permanently */

1544

ret = setuid(uid);

1545

if(ret == -1){

1546

perror("setuid");

1547

}

1548

}

1197

1549

}

1198

1550

1199

1551

if(quit_now){

1203

1555

ret = init_gnutls_global(pubkey, seckey);

1204

1556

if(ret == -1){

1205

1557

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

1206

exitcode = EXIT_FAILURE;

1558

exitcode = EX_UNAVAILABLE;

1207

1559

goto end;

1208

1560

} else {

1209

1561

gnutls_initialized = true;

1226

1578

1227

1579

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

1228

1580

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

1229

exitcode = EXIT_FAILURE;

1581

exitcode = EX_UNAVAILABLE;

1230

1582

goto end;

1231

1583

} else {

1232

1584

gpgme_initialized = true;

1242

1594

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

1243

1595

if(address == NULL){

1244

1596

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

1245

exitcode = EXIT_FAILURE;

1597

exitcode = EX_USAGE;

1246

1598

goto end;

1247

1599

}

1248

1600

1256

1608

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

1257

1609

or tmpmax != (uint16_t)tmpmax){

1258

1610

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

1259

exitcode = EXIT_FAILURE;

1611

exitcode = EX_USAGE;

1260

1612

goto end;

1261

1613

}

1262

1614

1278

1630

if(quit_now){

1279

1631

goto end;

1280

1632

}

1281

1282

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

1283

if(ret < 0){

1284

exitcode = EXIT_FAILURE;

1285

} else {

1633

1634

while(not quit_now){

1635

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

1636

if(quit_now or ret == 0){

1637

break;

1638

}

1639

sleep(15);

1640

};

1641

1642

if (not quit_now){

1286

1643

exitcode = EXIT_SUCCESS;

1287

1644

}

1645

1288

1646

goto end;

1289

1647

}

1290

1648

1314

1672

if(mc.server == NULL){

1315

1673

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

1316

1674

avahi_strerror(error));

1317

exitcode = EXIT_FAILURE;

1675

exitcode = EX_UNAVAILABLE;

1318

1676

goto end;

1319

1677

}

1320

1678

1329

1687

if(sb == NULL){

1330

1688

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

1331

1689

avahi_strerror(avahi_server_errno(mc.server)));

1332

exitcode = EXIT_FAILURE;

1690

exitcode = EX_UNAVAILABLE;

1333

1691

goto end;

1334

1692

}

1335

1693

1373

1731

1374

1732

/* Take down the network interface */

1375

1733

if(take_down_interface){

1376

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

1734

/* Re-raise priviliges */

1735

errno = 0;

1736

ret = seteuid(0);

1377

1737

if(ret == -1){

1378

perror("ioctl SIOCGIFFLAGS");

1379

} else if(network.ifr_flags & IFF_UP) {

1380

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

1381

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

1382

if(ret == -1){

1383

perror("ioctl SIOCSIFFLAGS");

1384

}

1738

perror("seteuid");

1385

1739

}

1386

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

1387

if(ret == -1){

1388

perror("close");

1740

if(geteuid() == 0){

1741

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

1742

if(ret == -1){

1743

perror("ioctl SIOCGIFFLAGS");

1744

} else if(network.ifr_flags & IFF_UP) {

1745

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

1746

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

1747

if(ret == -1){

1748

perror("ioctl SIOCSIFFLAGS -IFF_UP");

1749

}

1750

}

1751

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

1752

if(ret == -1){

1753

perror("close");

1754

}

1755

/* Lower privileges permanently */

1756

errno = 0;

1757

ret = setuid(uid);

1758

if(ret == -1){

1759

perror("setuid");

1760

}

1389

1761

}

1390

1762

}

1391

1763

1434

1806

}

1435

1807

1436

1808

if(quit_now){

1437

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

1809

sigemptyset(&old_sigterm_action.sa_mask);

1810

old_sigterm_action.sa_handler = SIG_DFL;

1811

ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,

1812

&old_sigterm_action,

1813

NULL));

1438

1814

if(ret == -1){

1439

1815

perror("sigaction");

1440

1816

}

1441

raise(signal_received);

1817

do {

1818

ret = raise(signal_received);

1819

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

1820

if(ret != 0){

1821

perror("raise");

1822

abort();

1823

}

1824

TEMP_FAILURE_RETRY(pause());

1442

1825

}

1443

1826

1444

1827

return exitcode;