/mandos/trunk : revision 478

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

80

argp_parse(), ARGP_KEY_ARG,

81

ARGP_KEY_END, ARGP_ERR_UNKNOWN */

82

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

83

sigaction(), SIGTERM, sigaction,

84

sig_atomic_t */

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

249

256

return false;

250

257

}

251

258

252

return true;

259

return true;

253

260

}

254

261

255

262

/*

309

316

}

310

317

gpgme_recipient_t recipient;

311

318

recipient = result->recipients;

312

if(recipient){

313

while(recipient != NULL){

314

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

315

gpgme_pubkey_algo_name(recipient->pubkey_algo));

316

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

317

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

318

recipient->status == GPG_ERR_NO_SECKEY

319

? "No" : "Yes");

320

recipient = recipient->next;

321

}

319

while(recipient != NULL){

320

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

321

gpgme_pubkey_algo_name(recipient->pubkey_algo));

322

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

323

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

324

recipient->status == GPG_ERR_NO_SECKEY

325

? "No" : "Yes");

326

recipient = recipient->next;

322

327

}

323

328

}

324

329

}

476

481

static int init_gnutls_session(gnutls_session_t *session){

477

482

int ret;

478

483

/* GnuTLS session creation */

479

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);

480

490

if(ret != GNUTLS_E_SUCCESS){

481

491

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

482

492

safer_gnutls_strerror(ret));

484

494

485

495

{

486

496

const char *err;

487

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);

488

504

if(ret != GNUTLS_E_SUCCESS){

489

505

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

490

506

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

494

510

}

495

511

}

496

512

497

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

498

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);

499

521

if(ret != GNUTLS_E_SUCCESS){

500

522

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

501

523

safer_gnutls_strerror(ret));

504

526

}

505

527

506

528

/* ignore client certificate if any. */

507

gnutls_certificate_server_set_request(*session,

508

GNUTLS_CERT_IGNORE);

529

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

509

530

510

531

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

511

532

520

541

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

521

542

AvahiIfIndex if_index,

522

543

int af){

523

int ret, tcp_sd;

544

int ret, tcp_sd = -1;

524

545

ssize_t sret;

525

546

union {

526

547

struct sockaddr_in in;

527

548

struct sockaddr_in6 in6;

528

549

} to;

529

550

char *buffer = NULL;

530

char *decrypted_buffer;

551

char *decrypted_buffer = NULL;

531

552

size_t buffer_length = 0;

532

553

size_t buffer_capacity = 0;

533

ssize_t decrypted_buffer_size;

534

554

size_t written;

535

int retval = 0;

555

int retval = -1;

536

556

gnutls_session_t session;

537

557

int pf; /* Protocol family */

538

558

559

errno = 0;

560

561

if(quit_now){

562

errno = EINTR;

563

return -1;

564

}

565

539

566

switch(af){

540

567

case AF_INET6:

541

568

pf = PF_INET6;

545

572

break;

546

573

default:

547

574

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

575

errno = EINVAL;

548

576

return -1;

549

577

}

550

578

560

588

561

589

tcp_sd = socket(pf, SOCK_STREAM, 0);

562

590

if(tcp_sd < 0){

591

int e = errno;

563

592

perror("socket");

564

return -1;

593

errno = e;

594

goto mandos_end;

595

}

596

597

if(quit_now){

598

errno = EINTR;

599

goto mandos_end;

565

600

}

566

601

567

602

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

573

608

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

574

609

}

575

610

if(ret < 0 ){

611

int e = errno;

576

612

perror("inet_pton");

577

return -1;

613

errno = e;

614

goto mandos_end;

578

615

}

579

616

if(ret == 0){

617

int e = errno;

580

618

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

581

return -1;

619

errno = e;

620

goto mandos_end;

582

621

}

583

622

if(af == AF_INET6){

584

623

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

591

630

if(if_index == AVAHI_IF_UNSPEC){

592

631

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

593

632

" without a network interface\n");

594

return -1;

633

errno = EINVAL;

634

goto mandos_end;

595

635

}

596

636

/* Set the network interface number as scope */

597

637

to.in6.sin6_scope_id = (uint32_t)if_index;

602

642

-Wunreachable-code */

603

643

}

604

644

645

if(quit_now){

646

errno = EINTR;

647

goto mandos_end;

648

}

649

605

650

if(debug){

606

651

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

607

652

char interface[IF_NAMESIZE];

634

679

}

635

680

}

636

681

682

if(quit_now){

683

errno = EINTR;

684

goto mandos_end;

685

}

686

637

687

if(af == AF_INET6){

638

688

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

639

689

} else {

640

690

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

641

691

}

642

692

if(ret < 0){

643

perror("connect");

644

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;

645

704

}

646

705

647

706

const char *out = mandos_protocol_version;

651

710

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

652

711

out_size - written));

653

712

if(ret == -1){

713

int e = errno;

654

714

perror("write");

655

retval = -1;

715

errno = e;

656

716

goto mandos_end;

657

717

}

658

718

written += (size_t)ret;

666

726

break;

667

727

}

668

728

}

729

730

if(quit_now){

731

errno = EINTR;

732

goto mandos_end;

733

}

669

734

}

670

735

671

736

if(debug){

672

737

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

673

738

}

674

739

740

if(quit_now){

741

errno = EINTR;

742

goto mandos_end;

743

}

744

675

745

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

676

746

677

do{

747

if(quit_now){

748

errno = EINTR;

749

goto mandos_end;

750

}

751

752

do {

678

753

ret = gnutls_handshake(session);

754

if(quit_now){

755

errno = EINTR;

756

goto mandos_end;

757

}

679

758

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

680

759

681

760

if(ret != GNUTLS_E_SUCCESS){

683

762

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

684

763

gnutls_perror(ret);

685

764

}

686

retval = -1;

765

errno = EPROTO;

687

766

goto mandos_end;

688

767

}

689

768

695

774

}

696

775

697

776

while(true){

777

778

if(quit_now){

779

errno = EINTR;

780

goto mandos_end;

781

}

782

698

783

buffer_capacity = incbuffer(&buffer, buffer_length,

699

784

buffer_capacity);

700

785

if(buffer_capacity == 0){

786

int e = errno;

701

787

perror("incbuffer");

702

retval = -1;

788

errno = e;

789

goto mandos_end;

790

}

791

792

if(quit_now){

793

errno = EINTR;

703

794

goto mandos_end;

704

795

}

705

796

714

805

case GNUTLS_E_AGAIN:

715

806

break;

716

807

case GNUTLS_E_REHANDSHAKE:

717

do{

808

do {

718

809

ret = gnutls_handshake(session);

810

811

if(quit_now){

812

errno = EINTR;

813

goto mandos_end;

814

}

719

815

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

720

816

if(ret < 0){

721

817

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

722

818

gnutls_perror(ret);

723

retval = -1;

819

errno = EPROTO;

724

820

goto mandos_end;

725

821

}

726

822

break;

727

823

default:

728

824

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

729

825

" encrypted session with Mandos server\n");

730

retval = -1;

731

826

gnutls_bye(session, GNUTLS_SHUT_RDWR);

827

errno = EIO;

732

828

goto mandos_end;

733

829

}

734

830

} else {

740

836

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

741

837

}

742

838

743

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);

744

851

745

852

if(buffer_length > 0){

853

ssize_t decrypted_buffer_size;

746

854

decrypted_buffer_size = pgp_packet_decrypt(buffer,

747

855

buffer_length,

748

856

&decrypted_buffer);

749

857

if(decrypted_buffer_size >= 0){

858

750

859

written = 0;

751

860

while(written < (size_t) decrypted_buffer_size){

861

if(quit_now){

862

errno = EINTR;

863

goto mandos_end;

864

}

865

752

866

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

753

867

(size_t)decrypted_buffer_size - written,

754

868

stdout);

755

869

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

870

int e = errno;

756

871

if(debug){

757

872

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

758

873

strerror(errno));

759

874

}

760

retval = -1;

761

break;

875

errno = e;

876

goto mandos_end;

762

877

}

763

878

written += (size_t)ret;

764

879

}

765

free(decrypted_buffer);

766

} else {

767

retval = -1;

880

retval = 0;

768

881

}

769

} else {

770

retval = -1;

771

882

}

772

883

773

884

/* Shutdown procedure */

774

885

775

886

mandos_end:

776

free(buffer);

777

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

778

if(ret == -1){

779

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;

780

906

}

781

gnutls_deinit(session);

782

907

return retval;

783

908

}

784

909

801

926

/* Called whenever a service has been resolved successfully or

802

927

timed out */

803

928

929

if(quit_now){

930

return;

931

}

932

804

933

switch(event){

805

934

default:

806

935

case AVAHI_RESOLVER_FAILURE:

843

972

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

844

973

is removed from the LAN */

845

974

975

if(quit_now){

976

return;

977

}

978

846

979

switch(event){

847

980

default:

848

981

case AVAHI_BROWSER_FAILURE:

877

1010

}

878

1011

}

879

1012

880

sig_atomic_t quit_now = 0;

881

882

1013

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

883

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

1014

static void handle_sigterm(int sig){

884

1015

if(quit_now){

885

1016

return;

886

1017

}

887

1018

quit_now = 1;

1019

signal_received = sig;

888

1020

int old_errno = errno;

889

1021

if(mc.simple_poll != NULL){

890

1022

avahi_simple_poll_quit(mc.simple_poll);

892

1024

errno = old_errno;

893

1025

}

894

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

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

1036

if_entry->d_name);

1037

if(ret < 0){

1038

perror("asprintf");

1039

return 0;

1040

}

1041

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

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

return 0;

1048

}

1049

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

1050

/* read line from flags_fd */

1051

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

1052

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

1053

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

1054

if(flagstring == NULL){

1055

perror("malloc");

1056

close(flags_fd);

1057

return 0;

1058

}

1059

while(to_read > 0){

1060

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

1061

(size_t)to_read));

1062

if(ssret == -1){

1063

perror("read");

1064

free(flagstring);

1065

close(flags_fd);

1066

return 0;

1067

}

1068

to_read -= ssret;

1069

if(ssret == 0){

1070

break;

1071

}

1072

}

1073

close(flags_fd);

1074

intmax_t tmpmax;

1075

char *tmp;

1076

errno = 0;

1077

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

1078

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

1079

and not (isspace(*tmp)))

1080

or tmpmax != (ifreq_flags)tmpmax){

1081

if(debug){

1082

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

1083

flagstring, if_entry->d_name);

1084

}

1085

free(flagstring);

1086

return 0;

1087

}

1088

free(flagstring);

1089

ifreq_flags flags = (ifreq_flags)tmpmax;

1090

/* Reject the loopback device */

1091

if(flags & IFF_LOOPBACK){

1092

if(debug){

1093

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

1094

if_entry->d_name);

1095

}

1096

return 0;

1097

}

1098

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

1099

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

1100

if(debug){

1101

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

1102

if_entry->d_name);

1103

}

1104

return 1;

1105

}

1106

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

1107

if(not (flags & IFF_BROADCAST)){

1108

if(debug){

1109

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

1110

if_entry->d_name);

1111

}

1112

return 0;

1113

}

1114

/* Accept this device */

1115

if(debug){

1116

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

1117

if_entry->d_name);

1118

}

1119

return 1;

1120

}

1121

895

1122

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

896

1123

AvahiSServiceBrowser *sb = NULL;

897

1124

int error;

899

1126

intmax_t tmpmax;

900

1127

char *tmp;

901

1128

int exitcode = EXIT_SUCCESS;

902

const char *interface = "eth0";

1129

const char *interface = "";

903

1130

struct ifreq network;

904

int sd;

1131

int sd = -1;

1132

bool take_down_interface = false;

905

1133

uid_t uid;

906

1134

gid_t gid;

907

char *connect_to = NULL;

908

1135

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

909

1136

bool tempdir_created = false;

910

1137

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

915

1142

bool gpgme_initialized = false;

916

1143

float delay = 2.5f;

917

1144

918

struct sigaction old_sigterm_action;

1145

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

919

1146

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

920

1147

1148

uid = getuid();

1149

gid = getgid();

1150

1151

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

1152

errno = 0;

1153

ret = setgid(gid);

1154

if(ret == -1){

1155

perror("setgid");

1156

}

1157

1158

/* Lower user privileges (temporarily) */

1159

errno = 0;

1160

ret = seteuid(uid);

1161

if(ret == -1){

1162

perror("seteuid");

1163

}

1164

1165

if(quit_now){

1166

goto end;

1167

}

1168

921

1169

{

922

1170

struct argp_option options[] = {

923

1171

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

952

1200

.arg = "SECONDS",

953

1201

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

954

1202

.group = 2 },

1203

/*

1204

* These reproduce what we would get without ARGP_NO_HELP

1205

*/

1206

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

1207

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

1208

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

1209

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

1210

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

1211

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

955

1212

{ .name = NULL }

956

1213

};

957

1214

958

1215

error_t parse_opt(int key, char *arg,

959

1216

struct argp_state *state){

1217

errno = 0;

960

1218

switch(key){

961

1219

case 128: /* --debug */

962

1220

debug = true;

978

1236

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

979

1237

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

980

1238

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

981

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

982

exit(EXIT_FAILURE);

1239

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

983

1240

}

984

1241

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

985

1242

break;

990

1247

errno = 0;

991

1248

delay = strtof(arg, &tmp);

992

1249

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

993

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

994

exit(EXIT_FAILURE);

1250

argp_error(state, "Bad delay");

995

1251

}

996

1252

break;

997

case ARGP_KEY_ARG:

998

argp_usage(state);

999

case ARGP_KEY_END:

1253

/*

1254

* These reproduce what we would get without ARGP_NO_HELP

1255

*/

1256

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

1257

argp_state_help(state, state->out_stream,

1258

(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)

1259

& ~(unsigned int)ARGP_HELP_EXIT_OK);

1260

case -3: /* --usage */

1261

argp_state_help(state, state->out_stream,

1262

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1263

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

1264

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

1265

exit(argp_err_exit_status);

1000

1266

break;

1001

1267

default:

1002

1268

return ARGP_ERR_UNKNOWN;

1003

1269

}

1004

return 0;

1270

return errno;

1005

1271

}

1006

1272

1007

1273

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

1008

1274

.args_doc = "",

1009

1275

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

1010

1276

" passwords from a Mandos server" };

1011

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

1012

if(ret == ARGP_ERR_UNKNOWN){

1013

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

1014

exitcode = EXIT_FAILURE;

1277

ret = argp_parse(&argp, argc, argv,

1278

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1279

switch(ret){

1280

case 0:

1281

break;

1282

case ENOMEM:

1283

default:

1284

errno = ret;

1285

perror("argp_parse");

1286

exitcode = EX_OSERR;

1287

goto end;

1288

case EINVAL:

1289

exitcode = EX_USAGE;

1015

1290

goto end;

1016

1291

}

1017

1292

}

1019

1294

if(not debug){

1020

1295

avahi_set_log_function(empty_log);

1021

1296

}

1297

1298

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

1299

struct dirent **direntries;

1300

ret = scandir(sys_class_net, &direntries, good_interface,

1301

alphasort);

1302

if(ret >= 1){

1303

/* Pick the first good interface */

1304

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

1305

if(debug){

1306

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

1307

}

1308

if(interface == NULL){

1309

perror("malloc");

1310

free(direntries);

1311

exitcode = EXIT_FAILURE;

1312

goto end;

1313

}

1314

free(direntries);

1315

} else {

1316

free(direntries);

1317

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

1318

exitcode = EXIT_FAILURE;

1319

goto end;

1320

}

1321

}

1022

1322

1023

1323

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

1024

1324

from the signal handler */

1027

1327

mc.simple_poll = avahi_simple_poll_new();

1028

1328

if(mc.simple_poll == NULL){

1029

1329

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

1030

exitcode = EXIT_FAILURE;

1330

exitcode = EX_UNAVAILABLE;

1031

1331

goto end;

1032

1332

}

1033

1333

1035

1335

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

1036

1336

if(ret == -1){

1037

1337

perror("sigaddset");

1038

exitcode = EXIT_FAILURE;

1338

exitcode = EX_OSERR;

1039

1339

goto end;

1040

1340

}

1041

1341

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

1042

1342

if(ret == -1){

1043

1343

perror("sigaddset");

1044

exitcode = EXIT_FAILURE;

1344

exitcode = EX_OSERR;

1045

1345

goto end;

1046

1346

}

1047

1347

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

1048

1348

if(ret == -1){

1049

1349

perror("sigaddset");

1050

exitcode = EXIT_FAILURE;

1051

goto end;

1052

}

1053

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

1054

if(ret == -1){

1055

perror("sigaction");

1056

exitcode = EXIT_FAILURE;

1057

goto end;

1058

}

1350

exitcode = EX_OSERR;

1351

goto end;

1352

}

1353

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

1354

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

1355

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

1356

*/

1357

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

1358

if(ret == -1){

1359

perror("sigaction");

1360

return EX_OSERR;

1361

}

1362

if(old_sigterm_action.sa_handler != SIG_IGN){

1363

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

1364

if(ret == -1){

1365

perror("sigaction");

1366

exitcode = EX_OSERR;

1367

goto end;

1368

}

1369

}

1370

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

1371

if(ret == -1){

1372

perror("sigaction");

1373

return EX_OSERR;

1374

}

1375

if(old_sigterm_action.sa_handler != SIG_IGN){

1376

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

1377

if(ret == -1){

1378

perror("sigaction");

1379

exitcode = EX_OSERR;

1380

goto end;

1381

}

1382

}

1383

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

1384

if(ret == -1){

1385

perror("sigaction");

1386

return EX_OSERR;

1387

}

1388

if(old_sigterm_action.sa_handler != SIG_IGN){

1389

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

1390

if(ret == -1){

1391

perror("sigaction");

1392

exitcode = EX_OSERR;

1393

goto end;

1394

}

1395

}

1059

1396

1060

1397

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

1061

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

1398

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

1399

if_index = (AvahiIfIndex) if_nametoindex(interface);

1400

if(if_index == 0){

1401

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

1402

exitcode = EX_UNAVAILABLE;

1403

goto end;

1404

}

1405

1406

if(quit_now){

1407

goto end;

1408

}

1409

1410

/* Re-raise priviliges */

1411

errno = 0;

1412

ret = seteuid(0);

1413

if(ret == -1){

1414

perror("seteuid");

1415

}

1416

1062

1417

#ifdef __linux__

1063

1418

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1064

messages to mess up the prompt */

1419

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

1065

1420

ret = klogctl(8, NULL, 5);

1066

1421

bool restore_loglevel = true;

1067

1422

if(ret == -1){

1073

1428

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1074

1429

if(sd < 0){

1075

1430

perror("socket");

1076

exitcode = EXIT_FAILURE;

1431

exitcode = EX_OSERR;

1077

1432

#ifdef __linux__

1078

1433

if(restore_loglevel){

1079

1434

ret = klogctl(7, NULL, 0);

1082

1437

}

1083

1438

}

1084

1439

#endif /* __linux__ */

1440

/* Lower privileges */

1441

errno = 0;

1442

ret = seteuid(uid);

1443

if(ret == -1){

1444

perror("seteuid");

1445

}

1085

1446

goto end;

1086

1447

}

1087

1448

strcpy(network.ifr_name, interface);

1096

1457

}

1097

1458

}

1098

1459

#endif /* __linux__ */

1099

exitcode = EXIT_FAILURE;

1460

exitcode = EX_OSERR;

1461

/* Lower privileges */

1462

errno = 0;

1463

ret = seteuid(uid);

1464

if(ret == -1){

1465

perror("seteuid");

1466

}

1100

1467

goto end;

1101

1468

}

1102

1469

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

1103

1470

network.ifr_flags |= IFF_UP;

1471

take_down_interface = true;

1104

1472

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

1105

1473

if(ret == -1){

1106

perror("ioctl SIOCSIFFLAGS");

1107

exitcode = EXIT_FAILURE;

1474

take_down_interface = false;

1475

perror("ioctl SIOCSIFFLAGS +IFF_UP");

1476

exitcode = EX_OSERR;

1108

1477

#ifdef __linux__

1109

1478

if(restore_loglevel){

1110

1479

ret = klogctl(7, NULL, 0);

1113

1482

}

1114

1483

}

1115

1484

#endif /* __linux__ */

1485

/* Lower privileges */

1486

errno = 0;

1487

ret = seteuid(uid);

1488

if(ret == -1){

1489

perror("seteuid");

1490

}

1116

1491

goto end;

1117

1492

}

1118

1493

}

1130

1505

perror("nanosleep");

1131

1506

}

1132

1507

}

1133

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

1134

if(ret == -1){

1135

perror("close");

1508

if(not take_down_interface){

1509

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

1510

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

1511

if(ret == -1){

1512

perror("close");

1513

}

1136

1514

}

1137

1515

#ifdef __linux__

1138

1516

if(restore_loglevel){

1143

1521

}

1144

1522

}

1145

1523

#endif /* __linux__ */

1146

}

1147

1148

uid = getuid();

1149

gid = getgid();

1150

1151

errno = 0;

1152

setgid(gid);

1153

if(ret == -1){

1154

perror("setgid");

1155

}

1156

1157

ret = setuid(uid);

1158

if(ret == -1){

1159

perror("setuid");

1524

/* Lower privileges */

1525

errno = 0;

1526

if(take_down_interface){

1527

/* Lower privileges */

1528

ret = seteuid(uid);

1529

if(ret == -1){

1530

perror("seteuid");

1531

}

1532

} else {

1533

/* Lower privileges permanently */

1534

ret = setuid(uid);

1535

if(ret == -1){

1536

perror("setuid");

1537

}

1538

}

1539

}

1540

1541

if(quit_now){

1542

goto end;

1160

1543

}

1161

1544

1162

1545

ret = init_gnutls_global(pubkey, seckey);

1163

1546

if(ret == -1){

1164

1547

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

1165

exitcode = EXIT_FAILURE;

1548

exitcode = EX_UNAVAILABLE;

1166

1549

goto end;

1167

1550

} else {

1168

1551

gnutls_initialized = true;

1169

1552

}

1170

1553

1554

if(quit_now){

1555

goto end;

1556

}

1557

1558

tempdir_created = true;

1171

1559

if(mkdtemp(tempdir) == NULL){

1560

tempdir_created = false;

1172

1561

perror("mkdtemp");

1173

1562

goto end;

1174

1563

}

1175

tempdir_created = true;

1564

1565

if(quit_now){

1566

goto end;

1567

}

1176

1568

1177

1569

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

1178

1570

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

1179

exitcode = EXIT_FAILURE;

1571

exitcode = EX_UNAVAILABLE;

1180

1572

goto end;

1181

1573

} else {

1182

1574

gpgme_initialized = true;

1183

1575

}

1184

1576

1185

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

1186

if_index = (AvahiIfIndex) if_nametoindex(interface);

1187

if(if_index == 0){

1188

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

1189

exitcode = EXIT_FAILURE;

1190

goto end;

1191

}

1577

if(quit_now){

1578

goto end;

1192

1579

}

1193

1580

1194

1581

if(connect_to != NULL){

1197

1584

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

1198

1585

if(address == NULL){

1199

1586

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

1200

exitcode = EXIT_FAILURE;

1201

goto end;

1202

}

1587

exitcode = EX_USAGE;

1588

goto end;

1589

}

1590

1591

if(quit_now){

1592

goto end;

1593

}

1594

1203

1595

uint16_t port;

1204

1596

errno = 0;

1205

1597

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

1206

1598

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

1207

1599

or tmpmax != (uint16_t)tmpmax){

1208

1600

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

1209

exitcode = EXIT_FAILURE;

1210

goto end;

1211

}

1601

exitcode = EX_USAGE;

1602

goto end;

1603

}

1604

1605

if(quit_now){

1606

goto end;

1607

}

1608

1212

1609

port = (uint16_t)tmpmax;

1213

1610

*address = '\0';

1214

1611

address = connect_to;

1219

1616

} else {

1220

1617

af = AF_INET;

1221

1618

}

1222

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

1223

if(ret < 0){

1224

exitcode = EXIT_FAILURE;

1225

} else {

1619

1620

if(quit_now){

1621

goto end;

1622

}

1623

1624

while(not quit_now){

1625

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

1626

if(quit_now or ret == 0){

1627

break;

1628

}

1629

sleep(15);

1630

};

1631

1632

if (not quit_now){

1226

1633

exitcode = EXIT_SUCCESS;

1227

1634

}

1228

goto end;

1229

}

1230

1635

1636

goto end;

1637

}

1638

1639

if(quit_now){

1640

goto end;

1641

}

1642

1231

1643

{

1232

1644

AvahiServerConfig config;

1233

1645

/* Do not publish any local Zeroconf records */

1250

1662

if(mc.server == NULL){

1251

1663

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

1252

1664

avahi_strerror(error));

1253

exitcode = EXIT_FAILURE;

1665

exitcode = EX_UNAVAILABLE;

1666

goto end;

1667

}

1668

1669

if(quit_now){

1254

1670

goto end;

1255

1671

}

1256

1672

1261

1677

if(sb == NULL){

1262

1678

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

1263

1679

avahi_strerror(avahi_server_errno(mc.server)));

1264

exitcode = EXIT_FAILURE;

1680

exitcode = EX_UNAVAILABLE;

1681

goto end;

1682

}

1683

1684

if(quit_now){

1265

1685

goto end;

1266

1686

}

1267

1687

1299

1719

gpgme_release(mc.ctx);

1300

1720

}

1301

1721

1722

/* Take down the network interface */

1723

if(take_down_interface){

1724

/* Re-raise priviliges */

1725

errno = 0;

1726

ret = seteuid(0);

1727

if(ret == -1){

1728

perror("seteuid");

1729

}

1730

if(geteuid() == 0){

1731

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

1732

if(ret == -1){

1733

perror("ioctl SIOCGIFFLAGS");

1734

} else if(network.ifr_flags & IFF_UP) {

1735

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

1736

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

1737

if(ret == -1){

1738

perror("ioctl SIOCSIFFLAGS -IFF_UP");

1739

}

1740

}

1741

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

1742

if(ret == -1){

1743

perror("close");

1744

}

1745

/* Lower privileges permanently */

1746

errno = 0;

1747

ret = setuid(uid);

1748

if(ret == -1){

1749

perror("setuid");

1750

}

1751

}

1752

}

1753

1302

1754

/* Removes the temp directory used by GPGME */

1303

1755

if(tempdir_created){

1304

1756

DIR *d;

1343

1795

}

1344

1796

}

1345

1797

1798

if(quit_now){

1799

sigemptyset(&old_sigterm_action.sa_mask);

1800

old_sigterm_action.sa_handler = SIG_DFL;

1801

ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,

1802

&old_sigterm_action,

1803

NULL));

1804

if(ret == -1){

1805

perror("sigaction");

1806

}

1807

do {

1808

ret = raise(signal_received);

1809

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

1810

if(ret != 0){

1811

perror("raise");

1812

abort();

1813

}

1814

TEMP_FAILURE_RETRY(pause());

1815

}

1816

1346

1817

return exitcode;

1347

1818

}