/mandos/release : revision 24.1.171

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));

568

603

if(af == AF_INET6){

569

to.in6.sin6_family = (uint16_t)af;

604

to.in6.sin6_family = (sa_family_t)af;

570

605

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

571

606

} else { /* IPv4 */

572

607

to.in.sin_family = (sa_family_t)af;

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

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

895

1132

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

896

1133

AvahiSServiceBrowser *sb = NULL;

897

1134

int error;

899

1136

intmax_t tmpmax;

900

1137

char *tmp;

901

1138

int exitcode = EXIT_SUCCESS;

902

const char *interface = "eth0";

1139

const char *interface = "";

903

1140

struct ifreq network;

904

int sd;

1141

int sd = -1;

1142

bool take_down_interface = false;

905

1143

uid_t uid;

906

1144

gid_t gid;

907

char *connect_to = NULL;

908

1145

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

909

1146

bool tempdir_created = false;

910

1147

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

915

1152

bool gpgme_initialized = false;

916

1153

float delay = 2.5f;

917

1154

918

struct sigaction old_sigterm_action;

1155

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

919

1156

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

920

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

921

1179

{

922

1180

struct argp_option options[] = {

923

1181

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

952

1210

.arg = "SECONDS",

953

1211

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

954

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 },

955

1222

{ .name = NULL }

956

1223

};

957

1224

958

1225

error_t parse_opt(int key, char *arg,

959

1226

struct argp_state *state){

1227

errno = 0;

960

1228

switch(key){

961

1229

case 128: /* --debug */

962

1230

debug = true;

978

1246

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

979

1247

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

980

1248

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

981

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

982

exit(EXIT_FAILURE);

1249

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

983

1250

}

984

1251

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

985

1252

break;

990

1257

errno = 0;

991

1258

delay = strtof(arg, &tmp);

992

1259

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

993

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

994

exit(EXIT_FAILURE);

1260

argp_error(state, "Bad delay");

995

1261

}

996

1262

break;

997

case ARGP_KEY_ARG:

998

argp_usage(state);

999

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);

1000

1276

break;

1001

1277

default:

1002

1278

return ARGP_ERR_UNKNOWN;

1003

1279

}

1004

return 0;

1280

return errno;

1005

1281

}

1006

1282

1007

1283

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

1008

1284

.args_doc = "",

1009

1285

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

1010

1286

" 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;

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;

1015

1300

goto end;

1016

1301

}

1017

1302

}

1019

1304

if(not debug){

1020

1305

avahi_set_log_function(empty_log);

1021

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

}

1022

1332

1023

1333

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

1024

1334

from the signal handler */

1027

1337

mc.simple_poll = avahi_simple_poll_new();

1028

1338

if(mc.simple_poll == NULL){

1029

1339

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

1030

exitcode = EXIT_FAILURE;

1340

exitcode = EX_UNAVAILABLE;

1031

1341

goto end;

1032

1342

}

1033

1343

1035

1345

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

1036

1346

if(ret == -1){

1037

1347

perror("sigaddset");

1038

exitcode = EXIT_FAILURE;

1348

exitcode = EX_OSERR;

1039

1349

goto end;

1040

1350

}

1041

1351

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

1042

1352

if(ret == -1){

1043

1353

perror("sigaddset");

1044

exitcode = EXIT_FAILURE;

1354

exitcode = EX_OSERR;

1045

1355

goto end;

1046

1356

}

1047

1357

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

1048

1358

if(ret == -1){

1049

1359

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

}

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

}

1405

}

1059

1406

1060

1407

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

1061

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

1408

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

1409

if_index = (AvahiIfIndex) if_nametoindex(interface);

1410

if(if_index == 0){

1411

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

1412

exitcode = EX_UNAVAILABLE;

1413

goto end;

1414

}

1415

1416

if(quit_now){

1417

goto end;

1418

}

1419

1420

/* Re-raise priviliges */

1421

errno = 0;

1422

ret = seteuid(0);

1423

if(ret == -1){

1424

perror("seteuid");

1425

}

1426

1062

1427

#ifdef __linux__

1063

1428

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1064

messages to mess up the prompt */

1429

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

1065

1430

ret = klogctl(8, NULL, 5);

1066

1431

bool restore_loglevel = true;

1067

1432

if(ret == -1){

1073

1438

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1074

1439

if(sd < 0){

1075

1440

perror("socket");

1076

exitcode = EXIT_FAILURE;

1441

exitcode = EX_OSERR;

1077

1442

#ifdef __linux__

1078

1443

if(restore_loglevel){

1079

1444

ret = klogctl(7, NULL, 0);

1082

1447

}

1083

1448

}

1084

1449

#endif /* __linux__ */

1450

/* Lower privileges */

1451

errno = 0;

1452

ret = seteuid(uid);

1453

if(ret == -1){

1454

perror("seteuid");

1455

}

1085

1456

goto end;

1086

1457

}

1087

1458

strcpy(network.ifr_name, interface);

1096

1467

}

1097

1468

}

1098

1469

#endif /* __linux__ */

1099

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

}

1100

1477

goto end;

1101

1478

}

1102

1479

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

1103

1480

network.ifr_flags |= IFF_UP;

1481

take_down_interface = true;

1104

1482

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

1105

1483

if(ret == -1){

1106

perror("ioctl SIOCSIFFLAGS");

1107

exitcode = EXIT_FAILURE;

1484

take_down_interface = false;

1485

perror("ioctl SIOCSIFFLAGS +IFF_UP");

1486

exitcode = EX_OSERR;

1108

1487

#ifdef __linux__

1109

1488

if(restore_loglevel){

1110

1489

ret = klogctl(7, NULL, 0);

1113

1492

}

1114

1493

}

1115

1494

#endif /* __linux__ */

1495

/* Lower privileges */

1496

errno = 0;

1497

ret = seteuid(uid);

1498

if(ret == -1){

1499

perror("seteuid");

1500

}

1116

1501

goto end;

1117

1502

}

1118

1503

}

1130

1515

perror("nanosleep");

1131

1516

}

1132

1517

}

1133

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

1134

if(ret == -1){

1135

perror("close");

1518

if(not take_down_interface){

1519

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

1520

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

1521

if(ret == -1){

1522

perror("close");

1523

}

1136

1524

}

1137

1525

#ifdef __linux__

1138

1526

if(restore_loglevel){

1143

1531

}

1144

1532

}

1145

1533

#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");

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

}

1549

}

1550

1551

if(quit_now){

1552

goto end;

1160

1553

}

1161

1554

1162

1555

ret = init_gnutls_global(pubkey, seckey);

1163

1556

if(ret == -1){

1164

1557

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

1165

exitcode = EXIT_FAILURE;

1558

exitcode = EX_UNAVAILABLE;

1166

1559

goto end;

1167

1560

} else {

1168

1561

gnutls_initialized = true;

1169

1562

}

1170

1563

1564

if(quit_now){

1565

goto end;

1566

}

1567

1568

tempdir_created = true;

1171

1569

if(mkdtemp(tempdir) == NULL){

1570

tempdir_created = false;

1172

1571

perror("mkdtemp");

1173

1572

goto end;

1174

1573

}

1175

tempdir_created = true;

1574

1575

if(quit_now){

1576

goto end;

1577

}

1176

1578

1177

1579

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

1178

1580

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

1179

exitcode = EXIT_FAILURE;

1581

exitcode = EX_UNAVAILABLE;

1180

1582

goto end;

1181

1583

} else {

1182

1584

gpgme_initialized = true;

1183

1585

}

1184

1586

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

}

1587

if(quit_now){

1588

goto end;

1192

1589

}

1193

1590

1194

1591

if(connect_to != NULL){

1197

1594

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

1198

1595

if(address == NULL){

1199

1596

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

1200

exitcode = EXIT_FAILURE;

1201

goto end;

1202

}

1597

exitcode = EX_USAGE;

1598

goto end;

1599

}

1600

1601

if(quit_now){

1602

goto end;

1603

}

1604

1203

1605

uint16_t port;

1204

1606

errno = 0;

1205

1607

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

1206

1608

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

1207

1609

or tmpmax != (uint16_t)tmpmax){

1208

1610

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

1209

exitcode = EXIT_FAILURE;

1210

goto end;

1211

}

1611

exitcode = EX_USAGE;

1612

goto end;

1613

}

1614

1615

if(quit_now){

1616

goto end;

1617

}

1618

1212

1619

port = (uint16_t)tmpmax;

1213

1620

*address = '\0';

1214

1621

address = connect_to;

1219

1626

} else {

1220

1627

af = AF_INET;

1221

1628

}

1222

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

1223

if(ret < 0){

1224

exitcode = EXIT_FAILURE;

1225

} else {

1629

1630

if(quit_now){

1631

goto end;

1632

}

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){

1226

1643

exitcode = EXIT_SUCCESS;

1227

1644

}

1228

goto end;

1229

}

1230

1645

1646

goto end;

1647

}

1648

1649

if(quit_now){

1650

goto end;

1651

}

1652

1231

1653

{

1232

1654

AvahiServerConfig config;

1233

1655

/* Do not publish any local Zeroconf records */

1250

1672

if(mc.server == NULL){

1251

1673

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

1252

1674

avahi_strerror(error));

1253

exitcode = EXIT_FAILURE;

1675

exitcode = EX_UNAVAILABLE;

1676

goto end;

1677

}

1678

1679

if(quit_now){

1254

1680

goto end;

1255

1681

}

1256

1682

1261

1687

if(sb == NULL){

1262

1688

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

1263

1689

avahi_strerror(avahi_server_errno(mc.server)));

1264

exitcode = EXIT_FAILURE;

1690

exitcode = EX_UNAVAILABLE;

1691

goto end;

1692

}

1693

1694

if(quit_now){

1265

1695

goto end;

1266

1696

}

1267

1697

1299

1729

gpgme_release(mc.ctx);

1300

1730

}

1301

1731

1732

/* Take down the network interface */

1733

if(take_down_interface){

1734

/* Re-raise priviliges */

1735

errno = 0;

1736

ret = seteuid(0);

1737

if(ret == -1){

1738

perror("seteuid");

1739

}

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

}

1761

}

1762

}

1763

1302

1764

/* Removes the temp directory used by GPGME */

1303

1765

if(tempdir_created){

1304

1766

DIR *d;

1343

1805

}

1344

1806

}

1345

1807

1808

if(quit_now){

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));

1814

if(ret == -1){

1815

perror("sigaction");

1816

}

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());

1825

}

1826

1346

1827

return exitcode;

1347

1828

}