/mandos/trunk : revision 237.2.19

71

INET_ADDRSTRLEN, INET6_ADDRSTRLEN

72

*/

73

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

74

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

74

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

75

setgid() */

76

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

77

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

80

argp_parse(), ARGP_KEY_ARG,

81

ARGP_KEY_END, ARGP_ERR_UNKNOWN */

82

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

83

sigaction(), SIGTERM, sig_atomic_t,

84

raise() */

83

sigaction(), SIGTERM, sigaction,

84

sig_atomic_t */

85

86

#ifdef __linux__

87

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

142

.dh_bits = 1024, .priority = "SECURE256"

143

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

144

145

sig_atomic_t quit_now = 0;

146

int signal_received = 0;

147

148

145

/*

149

146

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

150

147

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

167

164

*/

168

165

static bool init_gpgme(const char *seckey,

169

166

const char *pubkey, const char *tempdir){

167

int ret;

170

168

gpgme_error_t rc;

171

169

gpgme_engine_info_t engine_info;

172

170

175

173

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

176

174

*/

177

175

bool import_key(const char *filename){

178

int ret;

179

176

int fd;

180

177

gpgme_data_t pgp_data;

181

178

252

249

return false;

253

250

}

254

251

255

return true;

252

return true;

256

253

}

257

254

258

255

/*

312

309

}

313

310

gpgme_recipient_t recipient;

314

311

recipient = result->recipients;

315

while(recipient != NULL){

316

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

317

gpgme_pubkey_algo_name(recipient->pubkey_algo));

318

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

319

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

320

recipient->status == GPG_ERR_NO_SECKEY

321

? "No" : "Yes");

322

recipient = recipient->next;

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

}

323

322

}

324

323

}

325

324

}

477

476

static int init_gnutls_session(gnutls_session_t *session){

478

477

int ret;

479

478

/* GnuTLS session creation */

480

do {

481

ret = gnutls_init(session, GNUTLS_SERVER);

482

if(quit_now){

483

return -1;

484

}

485

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

479

ret = gnutls_init(session, GNUTLS_SERVER);

486

480

if(ret != GNUTLS_E_SUCCESS){

487

481

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

488

482

safer_gnutls_strerror(ret));

490

484

491

485

{

492

486

const char *err;

493

do {

494

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

495

if(quit_now){

496

gnutls_deinit(*session);

497

return -1;

498

}

499

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

487

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

500

488

if(ret != GNUTLS_E_SUCCESS){

501

489

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

502

490

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

506

494

}

507

495

}

508

496

509

do {

510

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

511

mc.cred);

512

if(quit_now){

513

gnutls_deinit(*session);

514

return -1;

515

}

516

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

497

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

498

mc.cred);

517

499

if(ret != GNUTLS_E_SUCCESS){

518

500

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

519

501

safer_gnutls_strerror(ret));

522

504

}

523

505

524

506

/* ignore client certificate if any. */

525

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

507

gnutls_certificate_server_set_request(*session,

508

GNUTLS_CERT_IGNORE);

526

509

527

510

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

528

511

537

520

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

538

521

AvahiIfIndex if_index,

539

522

int af){

540

int ret, tcp_sd = -1;

523

int ret, tcp_sd;

541

524

ssize_t sret;

542

525

union {

543

526

struct sockaddr_in in;

547

530

char *decrypted_buffer;

548

531

size_t buffer_length = 0;

549

532

size_t buffer_capacity = 0;

533

ssize_t decrypted_buffer_size;

550

534

size_t written;

551

535

int retval = 0;

552

536

gnutls_session_t session;

553

537

int pf; /* Protocol family */

554

538

555

if(quit_now){

556

return -1;

557

}

558

559

539

switch(af){

560

540

case AF_INET6:

561

541

pf = PF_INET6;

581

561

tcp_sd = socket(pf, SOCK_STREAM, 0);

582

562

if(tcp_sd < 0){

583

563

perror("socket");

584

retval = -1;

585

goto mandos_end;

586

}

587

588

if(quit_now){

589

retval = -1;

590

goto mandos_end;

564

return -1;

591

565

}

592

566

593

567

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

594

568

if(af == AF_INET6){

595

to.in6.sin6_family = (sa_family_t)af;

569

to.in6.sin6_family = (uint16_t)af;

596

570

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

597

571

} else { /* IPv4 */

598

572

to.in.sin_family = (sa_family_t)af;

600

574

}

601

575

if(ret < 0 ){

602

576

perror("inet_pton");

603

retval = -1;

604

goto mandos_end;

577

return -1;

605

578

}

606

579

if(ret == 0){

607

580

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

608

retval = -1;

609

goto mandos_end;

581

return -1;

610

582

}

611

583

if(af == AF_INET6){

612

584

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

619

591

if(if_index == AVAHI_IF_UNSPEC){

620

592

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

621

593

" without a network interface\n");

622

retval = -1;

623

goto mandos_end;

594

return -1;

624

595

}

625

596

/* Set the network interface number as scope */

626

597

to.in6.sin6_scope_id = (uint32_t)if_index;

631

602

-Wunreachable-code */

632

603

}

633

604

634

if(quit_now){

635

retval = -1;

636

goto mandos_end;

637

}

638

639

605

if(debug){

640

606

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

641

607

char interface[IF_NAMESIZE];

668

634

}

669

635

}

670

636

671

if(quit_now){

672

retval = -1;

673

goto mandos_end;

674

}

675

676

637

if(af == AF_INET6){

677

638

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

678

639

} else {

680

641

}

681

642

if(ret < 0){

682

643

perror("connect");

683

retval = -1;

684

goto mandos_end;

685

}

686

687

if(quit_now){

688

retval = -1;

689

goto mandos_end;

644

return -1;

690

645

}

691

646

692

647

const char *out = mandos_protocol_version;

711

666

break;

712

667

}

713

668

}

714

715

if(quit_now){

716

retval = -1;

717

goto mandos_end;

718

}

719

669

}

720

670

721

671

if(debug){

722

672

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

723

673

}

724

674

725

if(quit_now){

726

retval = -1;

727

goto mandos_end;

728

}

729

730

675

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

731

676

732

if(quit_now){

733

retval = -1;

734

goto mandos_end;

735

}

736

737

do {

677

do{

738

678

ret = gnutls_handshake(session);

739

if(quit_now){

740

retval = -1;

741

goto mandos_end;

742

}

743

679

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

744

680

745

681

if(ret != GNUTLS_E_SUCCESS){

759

695

}

760

696

761

697

while(true){

762

763

if(quit_now){

764

retval = -1;

765

goto mandos_end;

766

}

767

768

698

buffer_capacity = incbuffer(&buffer, buffer_length,

769

699

buffer_capacity);

770

700

if(buffer_capacity == 0){

773

703

goto mandos_end;

774

704

}

775

705

776

if(quit_now){

777

retval = -1;

778

goto mandos_end;

779

}

780

781

706

sret = gnutls_record_recv(session, buffer+buffer_length,

782

707

BUFFER_SIZE);

783

708

if(sret == 0){

789

714

case GNUTLS_E_AGAIN:

790

715

break;

791

716

case GNUTLS_E_REHANDSHAKE:

792

do {

717

do{

793

718

ret = gnutls_handshake(session);

794

795

if(quit_now){

796

retval = -1;

797

goto mandos_end;

798

}

799

719

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

800

720

if(ret < 0){

801

721

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

820

740

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

821

741

}

822

742

823

if(quit_now){

824

retval = -1;

825

goto mandos_end;

826

}

827

828

do {

829

ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);

830

if(quit_now){

831

retval = -1;

832

goto mandos_end;

833

}

834

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

743

gnutls_bye(session, GNUTLS_SHUT_RDWR);

835

744

836

745

if(buffer_length > 0){

837

ssize_t decrypted_buffer_size;

838

746

decrypted_buffer_size = pgp_packet_decrypt(buffer,

839

747

buffer_length,

840

748

&decrypted_buffer);

841

749

if(decrypted_buffer_size >= 0){

842

843

750

written = 0;

844

751

while(written < (size_t) decrypted_buffer_size){

845

if(quit_now){

846

retval = -1;

847

goto mandos_end;

848

}

849

850

752

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

851

753

(size_t)decrypted_buffer_size - written,

852

754

stdout);

872

774

873

775

mandos_end:

874

776

free(buffer);

875

if(tcp_sd >= 0){

876

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

877

}

777

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

878

778

if(ret == -1){

879

779

perror("close");

880

780

}

881

781

gnutls_deinit(session);

882

if(quit_now){

883

retval = -1;

884

}

885

782

return retval;

886

783

}

887

784

904

801

/* Called whenever a service has been resolved successfully or

905

802

timed out */

906

803

907

if(quit_now){

908

return;

909

}

910

911

804

switch(event){

912

805

default:

913

806

case AVAHI_RESOLVER_FAILURE:

950

843

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

951

844

is removed from the LAN */

952

845

953

if(quit_now){

954

return;

955

}

956

957

846

switch(event){

958

847

default:

959

848

case AVAHI_BROWSER_FAILURE:

988

877

}

989

878

}

990

879

880

sig_atomic_t quit_now = 0;

881

991

882

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

992

static void handle_sigterm(int sig){

883

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

993

884

if(quit_now){

994

885

return;

995

886

}

996

887

quit_now = 1;

997

signal_received = sig;

998

888

int old_errno = errno;

999

889

if(mc.simple_poll != NULL){

1000

890

avahi_simple_poll_quit(mc.simple_poll);

1011

901

int exitcode = EXIT_SUCCESS;

1012

902

const char *interface = "eth0";

1013

903

struct ifreq network;

1014

int sd = -1;

1015

bool take_down_interface = false;

904

int sd;

1016

905

uid_t uid;

1017

906

gid_t gid;

1018

907

char *connect_to = NULL;

1026

915

bool gpgme_initialized = false;

1027

916

float delay = 2.5f;

1028

917

1029

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

918

struct sigaction old_sigterm_action;

1030

919

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

1031

920

1032

uid = getuid();

1033

gid = getgid();

1034

1035

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

1036

errno = 0;

1037

ret = setgid(gid);

1038

if(ret == -1){

1039

perror("setgid");

1040

}

1041

1042

/* Lower user privileges (temporarily) */

1043

errno = 0;

1044

ret = seteuid(uid);

1045

if(ret == -1){

1046

perror("seteuid");

1047

}

1048

1049

if(quit_now){

1050

goto end;

1051

}

1052

1053

921

{

1054

922

struct argp_option options[] = {

1055

923

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

1182

1050

exitcode = EXIT_FAILURE;

1183

1051

goto end;

1184

1052

}

1185

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

1186

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

1187

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

1188

*/

1189

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

1190

if(ret == -1){

1191

perror("sigaction");

1192

return EXIT_FAILURE;

1193

}

1194

if(old_sigterm_action.sa_handler != SIG_IGN){

1195

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

1196

if(ret == -1){

1197

perror("sigaction");

1198

exitcode = EXIT_FAILURE;

1199

goto end;

1200

}

1201

}

1202

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

1203

if(ret == -1){

1204

perror("sigaction");

1205

return EXIT_FAILURE;

1206

}

1207

if(old_sigterm_action.sa_handler != SIG_IGN){

1208

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

1209

if(ret == -1){

1210

perror("sigaction");

1211

exitcode = EXIT_FAILURE;

1212

goto end;

1213

}

1214

}

1215

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

1216

if(ret == -1){

1217

perror("sigaction");

1218

return EXIT_FAILURE;

1219

}

1220

if(old_sigterm_action.sa_handler != SIG_IGN){

1221

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

1222

if(ret == -1){

1223

perror("sigaction");

1224

exitcode = EXIT_FAILURE;

1225

goto end;

1226

}

1227

}

1053

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

1054

if(ret == -1){

1055

perror("sigaction");

1056

exitcode = EXIT_FAILURE;

1057

goto end;

1058

}

1228

1059

1229

1060

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

1230

1061

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

1231

if_index = (AvahiIfIndex) if_nametoindex(interface);

1232

if(if_index == 0){

1233

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

1234

exitcode = EXIT_FAILURE;

1235

goto end;

1236

}

1237

1238

if(quit_now){

1239

goto end;

1240

}

1241

1242

/* Re-raise priviliges */

1243

errno = 0;

1244

ret = seteuid(0);

1245

if(ret == -1){

1246

perror("seteuid");

1247

}

1248

1249

1062

#ifdef __linux__

1250

1063

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1251

1064

messages to mess up the prompt */

1269

1082

}

1270

1083

}

1271

1084

#endif /* __linux__ */

1272

/* Lower privileges */

1273

errno = 0;

1274

ret = seteuid(uid);

1275

if(ret == -1){

1276

perror("seteuid");

1277

}

1278

1085

goto end;

1279

1086

}

1280

1087

strcpy(network.ifr_name, interface);

1290

1097

}

1291

1098

#endif /* __linux__ */

1292

1099

exitcode = EXIT_FAILURE;

1293

/* Lower privileges */

1294

errno = 0;

1295

ret = seteuid(uid);

1296

if(ret == -1){

1297

perror("seteuid");

1298

}

1299

1100

goto end;

1300

1101

}

1301

1102

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

1302

1103

network.ifr_flags |= IFF_UP;

1303

take_down_interface = true;

1304

1104

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

1305

1105

if(ret == -1){

1306

take_down_interface = false;

1307

1106

perror("ioctl SIOCSIFFLAGS");

1308

1107

exitcode = EXIT_FAILURE;

1309

1108

#ifdef __linux__

1314

1113

}

1315

1114

}

1316

1115

#endif /* __linux__ */

1317

/* Lower privileges */

1318

errno = 0;

1319

ret = seteuid(uid);

1320

if(ret == -1){

1321

perror("seteuid");

1322

}

1323

1116

goto end;

1324

1117

}

1325

1118

}

1337

1130

perror("nanosleep");

1338

1131

}

1339

1132

}

1340

if(not take_down_interface){

1341

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

1342

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

1343

if(ret == -1){

1344

perror("close");

1345

}

1133

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

1134

if(ret == -1){

1135

perror("close");

1346

1136

}

1347

1137

#ifdef __linux__

1348

1138

if(restore_loglevel){

1353

1143

}

1354

1144

}

1355

1145

#endif /* __linux__ */

1356

/* Lower privileges */

1357

errno = 0;

1358

if(take_down_interface){

1359

/* Lower privileges */

1360

ret = seteuid(uid);

1361

if(ret == -1){

1362

perror("seteuid");

1363

}

1364

} else {

1365

/* Lower privileges permanently */

1366

ret = setuid(uid);

1367

if(ret == -1){

1368

perror("setuid");

1369

}

1370

}

1371

}

1372

1373

if(quit_now){

1374

goto end;

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");

1375

1160

}

1376

1161

1377

1162

ret = init_gnutls_global(pubkey, seckey);

1383

1168

gnutls_initialized = true;

1384

1169

}

1385

1170

1386

if(quit_now){

1387

goto end;

1388

}

1389

1390

tempdir_created = true;

1391

1171

if(mkdtemp(tempdir) == NULL){

1392

tempdir_created = false;

1393

1172

perror("mkdtemp");

1394

1173

goto end;

1395

1174

}

1396

1397

if(quit_now){

1398

goto end;

1399

}

1175

tempdir_created = true;

1400

1176

1401

1177

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

1402

1178

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

1406

1182

gpgme_initialized = true;

1407

1183

}

1408

1184

1409

if(quit_now){

1410

goto end;

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

}

1411

1192

}

1412

1193

1413

1194

if(connect_to != NULL){

1419

1200

exitcode = EXIT_FAILURE;

1420

1201

goto end;

1421

1202

}

1422

1423

if(quit_now){

1424

goto end;

1425

}

1426

1427

1203

uint16_t port;

1428

1204

errno = 0;

1429

1205

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

1433

1209

exitcode = EXIT_FAILURE;

1434

1210

goto end;

1435

1211

}

1436

1437

if(quit_now){

1438

goto end;

1439

}

1440

1441

1212

port = (uint16_t)tmpmax;

1442

1213

*address = '\0';

1443

1214

address = connect_to;

1448

1219

} else {

1449

1220

af = AF_INET;

1450

1221

}

1451

1452

if(quit_now){

1453

goto end;

1454

}

1455

1456

1222

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

1457

1223

if(ret < 0){

1458

1224

exitcode = EXIT_FAILURE;

1461

1227

}

1462

1228

goto end;

1463

1229

}

1464

1465

if(quit_now){

1466

goto end;

1467

}

1468

1230

1469

1231

{

1470

1232

AvahiServerConfig config;

1471

1233

/* Do not publish any local Zeroconf records */

1492

1254

goto end;

1493

1255

}

1494

1256

1495

if(quit_now){

1496

goto end;

1497

}

1498

1499

1257

/* Create the Avahi service browser */

1500

1258

sb = avahi_s_service_browser_new(mc.server, if_index,

1501

1259

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

1507

1265

goto end;

1508

1266

}

1509

1267

1510

if(quit_now){

1511

goto end;

1512

}

1513

1514

1268

/* Run the main loop */

1515

1269

1516

1270

if(debug){

1545

1299

gpgme_release(mc.ctx);

1546

1300

}

1547

1301

1548

/* Take down the network interface */

1549

if(take_down_interface){

1550

/* Re-raise priviliges */

1551

errno = 0;

1552

ret = seteuid(0);

1553

if(ret == -1){

1554

perror("seteuid");

1555

}

1556

if(geteuid() == 0){

1557

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

1558

if(ret == -1){

1559

perror("ioctl SIOCGIFFLAGS");

1560

} else if(network.ifr_flags & IFF_UP) {

1561

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

1562

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

1563

if(ret == -1){

1564

perror("ioctl SIOCSIFFLAGS");

1565

}

1566

}

1567

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

1568

if(ret == -1){

1569

perror("close");

1570

}

1571

/* Lower privileges permanently */

1572

errno = 0;

1573

ret = setuid(uid);

1574

if(ret == -1){

1575

perror("setuid");

1576

}

1577

}

1578

}

1579

1580

1302

/* Removes the temp directory used by GPGME */

1581

1303

if(tempdir_created){

1582

1304

DIR *d;

1621

1343

}

1622

1344

}

1623

1345

1624

if(quit_now){

1625

sigemptyset(&old_sigterm_action.sa_mask);

1626

old_sigterm_action.sa_handler = SIG_DFL;

1627

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

1628

if(ret == -1){

1629

perror("sigaction");

1630

}

1631

raise(signal_received);

1632

}

1633

1634

1346

return exitcode;

1635

1347

}