/mandos/release : revision 237.7.261

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

32

/* Needed by GPGME, specifically gpgme_data_seek() */

33

#ifndef _LARGEFILE_SOURCE

34

#define _LARGEFILE_SOURCE

35

#endif

35

#endif /* not _LARGEFILE_SOURCE */

36

#ifndef _FILE_OFFSET_BITS

37

#define _FILE_OFFSET_BITS 64

38

#endif

38

#endif /* not _FILE_OFFSET_BITS */

39

40

#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */

41

42

#include <stdio.h> /* fprintf(), stderr, fwrite(),

43

stdout, ferror(), remove() */

43

stdout, ferror() */

44

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

45

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

46

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

55

opendir(), DIR */

56

#include <sys/stat.h> /* open(), S_ISREG */

57

#include <sys/socket.h> /* socket(), struct sockaddr_in6,

58

inet_pton(), connect() */

59

#include <fcntl.h> /* open() */

58

inet_pton(), connect(),

59

getnameinfo() */

60

#include <fcntl.h> /* open(), unlinkat() */

60

61

#include <dirent.h> /* opendir(), struct dirent, readdir()

61

62

*/

62

63

#include <inttypes.h> /* PRIu16, PRIdMAX, intmax_t,

72

73

*/

73

74

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

74

75

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

75

setgid(), pause(), _exit() */

76

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

76

setgid(), pause(), _exit(),

77

unlinkat() */

78

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

77

79

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

78

80

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

79

81

argp_state, struct argp,

91

93

argz_delete(), argz_append(),

92

94

argz_stringify(), argz_add(),

93

95

argz_count() */

96

#include <netdb.h> /* getnameinfo(), NI_NUMERICHOST,

97

EAI_SYSTEM, gai_strerror() */

94

98

95

99

#ifdef __linux__

96

100

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

138

142

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

139

143

char *connect_to = NULL;

140

144

const char *hookdir = HOOKDIR;

145

int hookdir_fd = -1;

141

146

uid_t uid = 65534;

142

147

gid_t gid = 65534;

143

148

180

185

perror(print_text);

181

186

}

182

187

183

__attribute__((format (gnu_printf, 2, 3)))

188

__attribute__((format (gnu_printf, 2, 3), nonnull))

184

189

int fprintf_plus(FILE *stream, const char *format, ...){

185

190

va_list ap;

186

191

va_start (ap, format);

195

200

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

196

201

* "buffer_length" is how much is already used.

197

202

*/

203

__attribute__((nonnull, warn_unused_result))

198

204

size_t incbuffer(char **buffer, size_t buffer_length,

199

205

size_t buffer_capacity){

200

206

if(buffer_length + BUFFER_SIZE > buffer_capacity){

213

219

}

214

220

215

221

/* Add server to set of servers to retry periodically */

222

__attribute__((nonnull, warn_unused_result))

216

223

bool add_server(const char *ip, in_port_t port, AvahiIfIndex if_index,

217

224

int af, server **current_server){

218

225

int ret;

227

234

.af = af };

228

235

if(new_server->ip == NULL){

229

236

perror_plus("strdup");

237

free(new_server);

238

return false;

239

}

240

ret = clock_gettime(CLOCK_MONOTONIC, &(new_server->last_seen));

241

if(ret == -1){

242

perror_plus("clock_gettime");

243

free(new_server->ip);

244

free(new_server);

230

245

return false;

231

246

}

232

247

/* Special case of first server */

234

249

new_server->next = new_server;

235

250

new_server->prev = new_server;

236

251

*current_server = new_server;

237

/* Place the new server last in the list */

238

252

} else {

253

/* Place the new server last in the list */

239

254

new_server->next = *current_server;

240

255

new_server->prev = (*current_server)->prev;

241

256

new_server->prev->next = new_server;

242

257

(*current_server)->prev = new_server;

243

258

}

244

ret = clock_gettime(CLOCK_MONOTONIC, &(*current_server)->last_seen);

245

if(ret == -1){

246

perror_plus("clock_gettime");

247

return false;

248

}

249

259

return true;

250

260

}

251

261

252

262

/*

253

263

* Initialize GPGME.

254

264

*/

255

static bool init_gpgme(const char *seckey, const char *pubkey,

256

const char *tempdir, mandos_context *mc){

265

__attribute__((nonnull, warn_unused_result))

266

static bool init_gpgme(const char * const seckey,

267

const char * const pubkey,

268

const char * const tempdir,

269

mandos_context *mc){

257

270

gpgme_error_t rc;

258

271

gpgme_engine_info_t engine_info;

259

272

260

273

/*

261

274

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

262

275

*/

263

bool import_key(const char *filename){

276

bool import_key(const char * const filename){

264

277

int ret;

265

278

int fd;

266

279

gpgme_data_t pgp_data;

347

360

* Decrypt OpenPGP data.

348

361

* Returns -1 on error

349

362

*/

363

__attribute__((nonnull, warn_unused_result))

350

364

static ssize_t pgp_packet_decrypt(const char *cryptotext,

351

365

size_t crypto_size,

352

366

char **plaintext,

472

486

return plaintext_length;

473

487

}

474

488

475

static const char * safer_gnutls_strerror(int value){

489

__attribute__((warn_unused_result))

490

static const char *safer_gnutls_strerror(int value){

476

491

const char *ret = gnutls_strerror(value);

477

492

if(ret == NULL)

478

493

ret = "(unknown)";

480

495

}

481

496

482

497

/* GnuTLS log function callback */

498

__attribute__((nonnull))

483

499

static void debuggnutls(__attribute__((unused)) int level,

484

500

const char* string){

485

501

fprintf_plus(stderr, "GnuTLS: %s", string);

486

502

}

487

503

504

__attribute__((nonnull, warn_unused_result))

488

505

static int init_gnutls_global(const char *pubkeyfilename,

489

506

const char *seckeyfilename,

490

507

mandos_context *mc){

564

581

return -1;

565

582

}

566

583

584

__attribute__((nonnull, warn_unused_result))

567

585

static int init_gnutls_session(gnutls_session_t *session,

568

586

mandos_context *mc){

569

587

int ret;

626

644

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

627

645

628

646

/* Called when a Mandos server is found */

647

__attribute__((nonnull, warn_unused_result))

629

648

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

630

649

AvahiIfIndex if_index,

631

650

int af, mandos_context *mc){

632

651

int ret, tcp_sd = -1;

633

652

ssize_t sret;

634

union {

635

struct sockaddr_in in;

636

struct sockaddr_in6 in6;

637

} to;

653

struct sockaddr_storage to;

638

654

char *buffer = NULL;

639

655

char *decrypted_buffer = NULL;

640

656

size_t buffer_length = 0;

721

737

722

738

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

723

739

if(af == AF_INET6){

724

to.in6.sin6_family = (sa_family_t)af;

725

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

740

((struct sockaddr_in6 *)&to)->sin6_family = (sa_family_t)af;

741

ret = inet_pton(af, ip, &((struct sockaddr_in6 *)&to)->sin6_addr);

726

742

} else { /* IPv4 */

727

to.in.sin_family = (sa_family_t)af;

728

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

743

((struct sockaddr_in *)&to)->sin_family = (sa_family_t)af;

744

ret = inet_pton(af, ip, &((struct sockaddr_in *)&to)->sin_addr);

729

745

}

730

746

if(ret < 0 ){

731

747

int e = errno;

740

756

goto mandos_end;

741

757

}

742

758

if(af == AF_INET6){

743

to.in6.sin6_port = htons(port);

744

#ifdef __GNUC__

745

#pragma GCC diagnostic push

746

#pragma GCC diagnostic ignored "-Wstrict-aliasing"

747

#endif

748

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

749

(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower */

750

#ifdef __GNUC__

751

#pragma GCC diagnostic pop

752

#endif

759

((struct sockaddr_in6 *)&to)->sin6_port = htons(port);

760

if(IN6_IS_ADDR_LINKLOCAL

761

(&((struct sockaddr_in6 *)&to)->sin6_addr)){

753

762

if(if_index == AVAHI_IF_UNSPEC){

754

763

fprintf_plus(stderr, "An IPv6 link-local address is"

755

764

" incomplete without a network interface\n");

757

766

goto mandos_end;

758

767

}

759

768

/* Set the network interface number as scope */

760

to.in6.sin6_scope_id = (uint32_t)if_index;

769

((struct sockaddr_in6 *)&to)->sin6_scope_id = (uint32_t)if_index;

761

770

}

762

771

} else {

763

to.in.sin_port = htons(port);

772

((struct sockaddr_in *)&to)->sin_port = htons(port);

764

773

}

765

774

766

775

if(quit_now){

783

792

}

784

793

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

785

794

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

786

const char *pcret;

787

795

if(af == AF_INET6){

788

pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,

789

sizeof(addrstr));

796

ret = getnameinfo((struct sockaddr *)&to,

797

sizeof(struct sockaddr_in6),

798

addrstr, sizeof(addrstr), NULL, 0,

799

NI_NUMERICHOST);

790

800

} else {

791

pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,

792

sizeof(addrstr));

801

ret = getnameinfo((struct sockaddr *)&to,

802

sizeof(struct sockaddr_in),

803

addrstr, sizeof(addrstr), NULL, 0,

804

NI_NUMERICHOST);

793

805

}

794

if(pcret == NULL){

795

perror_plus("inet_ntop");

796

} else {

797

if(strcmp(addrstr, ip) != 0){

798

fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);

799

}

806

if(ret == EAI_SYSTEM){

807

perror_plus("getnameinfo");

808

} else if(ret != 0) {

809

fprintf_plus(stderr, "getnameinfo: %s", gai_strerror(ret));

810

} else if(strcmp(addrstr, ip) != 0){

811

fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);

800

812

}

801

813

}

802

814

806

818

}

807

819

808

820

if(af == AF_INET6){

809

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

821

ret = connect(tcp_sd, (struct sockaddr *)&to,

822

sizeof(struct sockaddr_in6));

810

823

} else {

811

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

824

ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */

825

sizeof(struct sockaddr_in));

812

826

}

813

827

if(ret < 0){

814

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

828

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

815

829

int e = errno;

816

830

perror_plus("connect");

817

831

errno = e;

1032

1046

return retval;

1033

1047

}

1034

1048

1049

__attribute__((nonnull))

1035

1050

static void resolve_callback(AvahiSServiceResolver *r,

1036

1051

AvahiIfIndex interface,

1037

1052

AvahiProtocol proto,

1045

1060

AVAHI_GCC_UNUSED AvahiStringList *txt,

1046

1061

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1047

1062

flags,

1048

void* mc){

1063

void *mc){

1049

1064

if(r == NULL){

1050

1065

return;

1051

1066

}

1104

1119

const char *domain,

1105

1120

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1106

1121

flags,

1107

void* mc){

1122

void *mc){

1108

1123

if(b == NULL){

1109

1124

return;

1110

1125

}

1170

1185

errno = old_errno;

1171

1186

}

1172

1187

1188

__attribute__((nonnull, warn_unused_result))

1173

1189

bool get_flags(const char *ifname, struct ifreq *ifr){

1174

1190

int ret;

1175

1191

error_t ret_errno;

1194

1210

return true;

1195

1211

}

1196

1212

1213

__attribute__((nonnull, warn_unused_result))

1197

1214

bool good_flags(const char *ifname, const struct ifreq *ifr){

1198

1215

1199

1216

/* Reject the loopback device */

1241

1258

* corresponds to an acceptable network device.

1242

1259

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

1243

1260

*/

1261

__attribute__((nonnull, warn_unused_result))

1244

1262

int good_interface(const struct dirent *if_entry){

1245

1263

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

1246

1264

return 0;

1264

1282

/*

1265

1283

* This function determines if a network interface is up.

1266

1284

*/

1285

__attribute__((nonnull, warn_unused_result))

1267

1286

bool interface_is_up(const char *interface){

1268

1287

struct ifreq ifr;

1269

1288

if(not get_flags(interface, &ifr)){

1280

1299

/*

1281

1300

* This function determines if a network interface is running

1282

1301

*/

1302

__attribute__((nonnull, warn_unused_result))

1283

1303

bool interface_is_running(const char *interface){

1284

1304

struct ifreq ifr;

1285

1305

if(not get_flags(interface, &ifr)){

1293

1313

return (bool)(ifr.ifr_flags & IFF_RUNNING);

1294

1314

}

1295

1315

1316

__attribute__((nonnull, pure, warn_unused_result))

1296

1317

int notdotentries(const struct dirent *direntry){

1297

1318

/* Skip "." and ".." */

1298

1319

if(direntry->d_name[0] == '.'

1305

1326

}

1306

1327

1307

1328

/* Is this directory entry a runnable program? */

1329

__attribute__((nonnull, warn_unused_result))

1308

1330

int runnable_hook(const struct dirent *direntry){

1309

1331

int ret;

1310

1332

size_t sret;

1318

1340

sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"

1319

1341

"abcdefghijklmnopqrstuvwxyz"

1320

1342

"0123456789"

1321

"_-");

1343

"_.-");

1322

1344

if((direntry->d_name)[sret] != '\0'){

1323

1345

/* Contains non-allowed characters */

1324

1346

if(debug){

1328

1350

return 0;

1329

1351

}

1330

1352

1331

char *fullname = NULL;

1332

ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);

1333

if(ret < 0){

1334

perror_plus("asprintf");

1335

return 0;

1336

}

1337

1338

ret = stat(fullname, &st);

1353

ret = fstatat(hookdir_fd, direntry->d_name, &st, 0);

1339

1354

if(ret == -1){

1340

1355

if(debug){

1341

1356

perror_plus("Could not stat hook");

1365

1380

return 1;

1366

1381

}

1367

1382

1383

__attribute__((nonnull, warn_unused_result))

1368

1384

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1369

1385

mandos_context *mc){

1370

1386

int ret;

1374

1390

1375

1391

while(true){

1376

1392

if(mc->current_server == NULL){

1377

if (debug){

1393

if(debug){

1378

1394

fprintf_plus(stderr, "Wait until first server is found."

1379

1395

" No timeout!\n");

1380

1396

}

1381

1397

ret = avahi_simple_poll_iterate(s, -1);

1382

1398

} else {

1383

if (debug){

1399

if(debug){

1384

1400

fprintf_plus(stderr, "Check current_server if we should run"

1385

1401

" it, or wait\n");

1386

1402

}

1403

1419

- ((intmax_t)waited_time.tv_sec * 1000))

1404

1420

- ((intmax_t)waited_time.tv_nsec / 1000000));

1405

1421

1406

if (debug){

1422

if(debug){

1407

1423

fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",

1408

1424

block_time);

1409

1425

}

1431

1447

ret = avahi_simple_poll_iterate(s, (int)block_time);

1432

1448

}

1433

1449

if(ret != 0){

1434

if (ret > 0 or errno != EINTR){

1450

if(ret > 0 or errno != EINTR){

1435

1451

return (ret != 1) ? ret : 0;

1436

1452

}

1437

1453

}

1439

1455

}

1440

1456

1441

1457

/* Set effective uid to 0, return errno */

1458

__attribute__((warn_unused_result))

1442

1459

error_t raise_privileges(void){

1443

1460

error_t old_errno = errno;

1444

1461

error_t ret_errno = 0;

1445

1462

if(seteuid(0) == -1){

1446

1463

ret_errno = errno;

1447

perror_plus("seteuid");

1448

1464

}

1449

1465

errno = old_errno;

1450

1466

return ret_errno;

1451

1467

}

1452

1468

1453

1469

/* Set effective and real user ID to 0. Return errno. */

1470

__attribute__((warn_unused_result))

1454

1471

error_t raise_privileges_permanently(void){

1455

1472

error_t old_errno = errno;

1456

1473

error_t ret_errno = raise_privileges();

1460

1477

}

1461

1478

if(setuid(0) == -1){

1462

1479

ret_errno = errno;

1463

perror_plus("seteuid");

1464

1480

}

1465

1481

errno = old_errno;

1466

1482

return ret_errno;

1467

1483

}

1468

1484

1469

1485

/* Set effective user ID to unprivileged saved user ID */

1486

__attribute__((warn_unused_result))

1470

1487

error_t lower_privileges(void){

1471

1488

error_t old_errno = errno;

1472

1489

error_t ret_errno = 0;

1473

1490

if(seteuid(uid) == -1){

1474

1491

ret_errno = errno;

1475

perror_plus("seteuid");

1476

1492

}

1477

1493

errno = old_errno;

1478

1494

return ret_errno;

1479

1495

}

1480

1496

1481

1497

/* Lower privileges permanently */

1498

__attribute__((warn_unused_result))

1482

1499

error_t lower_privileges_permanently(void){

1483

1500

error_t old_errno = errno;

1484

1501

error_t ret_errno = 0;

1485

1502

if(setuid(uid) == -1){

1486

1503

ret_errno = errno;

1487

perror_plus("setuid");

1488

1504

}

1489

1505

errno = old_errno;

1490

1506

return ret_errno;

1491

1507

}

1492

1508

1493

bool run_network_hooks(const char *mode, const char *interface,

1509

__attribute__((nonnull))

1510

void run_network_hooks(const char *mode, const char *interface,

1494

1511

const float delay){

1495

struct dirent **direntries;

1496

int numhooks = scandir(hookdir, &direntries, runnable_hook,

1497

alphasort);

1512

struct dirent **direntries = NULL;

1513

if(hookdir_fd == -1){

1514

hookdir_fd = open(hookdir, O_RDONLY);

1515

if(hookdir_fd == -1){

1516

if(errno == ENOENT){

1517

if(debug){

1518

fprintf_plus(stderr, "Network hook directory \"%s\" not"

1519

" found\n", hookdir);

1520

}

1521

} else {

1522

perror_plus("open");

1523

}

1524

return;

1525

}

1526

}

1527

#ifdef __GLIBC__

1528

#if __GLIBC_PREREQ(2, 15)

1529

int numhooks = scandirat(hookdir_fd, ".", &direntries,

1530

runnable_hook, alphasort);

1531

#else /* not __GLIBC_PREREQ(2, 15) */

1532

int numhooks = scandir(hookdir, &direntries, runnable_hook,

1533

alphasort);

1534

#endif /* not __GLIBC_PREREQ(2, 15) */

1535

#else /* not __GLIBC__ */

1536

int numhooks = scandir(hookdir, &direntries, runnable_hook,

1537

alphasort);

1538

#endif /* not __GLIBC__ */

1498

1539

if(numhooks == -1){

1499

if(errno == ENOENT){

1500

if(debug){

1501

fprintf_plus(stderr, "Network hook directory \"%s\" not"

1502

" found\n", hookdir);

1503

}

1504

} else {

1505

perror_plus("scandir");

1540

perror_plus("scandir");

1541

return;

1542

}

1543

struct dirent *direntry;

1544

int ret;

1545

int devnull = open("/dev/null", O_RDONLY);

1546

for(int i = 0; i < numhooks; i++){

1547

direntry = direntries[i];

1548

if(debug){

1549

fprintf_plus(stderr, "Running network hook \"%s\"\n",

1550

direntry->d_name);

1506

1551

}

1507

} else {

1508

struct dirent *direntry;

1509

int ret;

1510

int devnull = open("/dev/null", O_RDONLY);

1511

for(int i = 0; i < numhooks; i++){

1512

direntry = direntries[i];

1513

char *fullname = NULL;

1514

ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);

1515

if(ret < 0){

1552

pid_t hook_pid = fork();

1553

if(hook_pid == 0){

1554

/* Child */

1555

/* Raise privileges */

1556

errno = raise_privileges_permanently();

1557

if(errno != 0){

1558

perror_plus("Failed to raise privileges");

1559

_exit(EX_NOPERM);

1560

}

1561

/* Set group */

1562

errno = 0;

1563

ret = setgid(0);

1564

if(ret == -1){

1565

perror_plus("setgid");

1566

_exit(EX_NOPERM);

1567

}

1568

/* Reset supplementary groups */

1569

errno = 0;

1570

ret = setgroups(0, NULL);

1571

if(ret == -1){

1572

perror_plus("setgroups");

1573

_exit(EX_NOPERM);

1574

}

1575

ret = dup2(devnull, STDIN_FILENO);

1576

if(ret == -1){

1577

perror_plus("dup2(devnull, STDIN_FILENO)");

1578

_exit(EX_OSERR);

1579

}

1580

ret = close(devnull);

1581

if(ret == -1){

1582

perror_plus("close");

1583

_exit(EX_OSERR);

1584

}

1585

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1586

if(ret == -1){

1587

perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");

1588

_exit(EX_OSERR);

1589

}

1590

ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);

1591

if(ret == -1){

1592

perror_plus("setenv");

1593

_exit(EX_OSERR);

1594

}

1595

ret = setenv("DEVICE", interface, 1);

1596

if(ret == -1){

1597

perror_plus("setenv");

1598

_exit(EX_OSERR);

1599

}

1600

ret = setenv("VERBOSITY", debug ? "1" : "0", 1);

1601

if(ret == -1){

1602

perror_plus("setenv");

1603

_exit(EX_OSERR);

1604

}

1605

ret = setenv("MODE", mode, 1);

1606

if(ret == -1){

1607

perror_plus("setenv");

1608

_exit(EX_OSERR);

1609

}

1610

char *delaystring;

1611

ret = asprintf(&delaystring, "%f", (double)delay);

1612

if(ret == -1){

1516

1613

perror_plus("asprintf");

1517

continue;

1518

}

1519

if(debug){

1520

fprintf_plus(stderr, "Running network hook \"%s\"\n",

1521

direntry->d_name);

1522

}

1523

pid_t hook_pid = fork();

1524

if(hook_pid == 0){

1525

/* Child */

1526

/* Raise privileges */

1527

raise_privileges_permanently();

1528

/* Set group */

1529

errno = 0;

1530

ret = setgid(0);

1531

if(ret == -1){

1532

perror_plus("setgid");

1533

}

1534

/* Reset supplementary groups */

1535

errno = 0;

1536

ret = setgroups(0, NULL);

1537

if(ret == -1){

1538

perror_plus("setgroups");

1539

}

1540

dup2(devnull, STDIN_FILENO);

1541

close(devnull);

1542

dup2(STDERR_FILENO, STDOUT_FILENO);

1543

ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);

1544

if(ret == -1){

1545

perror_plus("setenv");

1546

_exit(EX_OSERR);

1547

}

1548

ret = setenv("DEVICE", interface, 1);

1549

if(ret == -1){

1550

perror_plus("setenv");

1551

_exit(EX_OSERR);

1552

}

1553

ret = setenv("VERBOSITY", debug ? "1" : "0", 1);

1554

if(ret == -1){

1555

perror_plus("setenv");

1556

_exit(EX_OSERR);

1557

}

1558

ret = setenv("MODE", mode, 1);

1559

if(ret == -1){

1560

perror_plus("setenv");

1561

_exit(EX_OSERR);

1562

}

1563

char *delaystring;

1564

ret = asprintf(&delaystring, "%f", delay);

1565

if(ret == -1){

1566

perror_plus("asprintf");

1567

_exit(EX_OSERR);

1568

}

1569

ret = setenv("DELAY", delaystring, 1);

1570

if(ret == -1){

1571

free(delaystring);

1572

perror_plus("setenv");

1573

_exit(EX_OSERR);

1574

}

1614

_exit(EX_OSERR);

1615

}

1616

ret = setenv("DELAY", delaystring, 1);

1617

if(ret == -1){

1575

1618

free(delaystring);

1576

if(connect_to != NULL){

1577

ret = setenv("CONNECT", connect_to, 1);

1578

if(ret == -1){

1579

perror_plus("setenv");

1580

_exit(EX_OSERR);

1581

}

1582

}

1583

if(execl(fullname, direntry->d_name, mode, NULL) == -1){

1584

perror_plus("execl");

1585

_exit(EXIT_FAILURE);

1586

}

1619

perror_plus("setenv");

1620

_exit(EX_OSERR);

1621

}

1622

free(delaystring);

1623

if(connect_to != NULL){

1624

ret = setenv("CONNECT", connect_to, 1);

1625

if(ret == -1){

1626

perror_plus("setenv");

1627

_exit(EX_OSERR);

1628

}

1629

}

1630

int hook_fd = openat(hookdir_fd, direntry->d_name, O_RDONLY);

1631

if(hook_fd == -1){

1632

perror_plus("openat");

1633

_exit(EXIT_FAILURE);

1634

}

1635

if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){

1636

perror_plus("close");

1637

_exit(EXIT_FAILURE);

1638

}

1639

if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },

1640

environ) == -1){

1641

perror_plus("fexecve");

1642

_exit(EXIT_FAILURE);

1643

}

1644

} else {

1645

int status;

1646

if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){

1647

perror_plus("waitpid");

1648

continue;

1649

}

1650

if(WIFEXITED(status)){

1651

if(WEXITSTATUS(status) != 0){

1652

fprintf_plus(stderr, "Warning: network hook \"%s\" exited"

1653

" with status %d\n", direntry->d_name,

1654

WEXITSTATUS(status));

1655

continue;

1656

}

1657

} else if(WIFSIGNALED(status)){

1658

fprintf_plus(stderr, "Warning: network hook \"%s\" died by"

1659

" signal %d\n", direntry->d_name,

1660

WTERMSIG(status));

1661

continue;

1587

1662

} else {

1588

int status;

1589

if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){

1590

perror_plus("waitpid");

1591

free(fullname);

1592

continue;

1593

}

1594

if(WIFEXITED(status)){

1595

if(WEXITSTATUS(status) != 0){

1596

fprintf_plus(stderr, "Warning: network hook \"%s\" exited"

1597

" with status %d\n", direntry->d_name,

1598

WEXITSTATUS(status));

1599

free(fullname);

1600

continue;

1601

}

1602

} else if(WIFSIGNALED(status)){

1603

fprintf_plus(stderr, "Warning: network hook \"%s\" died by"

1604

" signal %d\n", direntry->d_name,

1605

WTERMSIG(status));

1606

free(fullname);

1607

continue;

1608

} else {

1609

fprintf_plus(stderr, "Warning: network hook \"%s\""

1610

" crashed\n", direntry->d_name);

1611

free(fullname);

1612

continue;

1613

}

1614

}

1615

free(fullname);

1616

if(debug){

1617

fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",

1618

direntry->d_name);

1619

}

1620

}

1621

close(devnull);

1622

}

1623

return true;

1663

fprintf_plus(stderr, "Warning: network hook \"%s\""

1664

" crashed\n", direntry->d_name);

1665

continue;

1666

}

1667

}

1668

if(debug){

1669

fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",

1670

direntry->d_name);

1671

}

1672

}

1673

free(direntries);

1674

if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){

1675

perror_plus("close");

1676

} else {

1677

hookdir_fd = -1;

1678

}

1679

close(devnull);

1624

1680

}

1625

1681

1682

__attribute__((nonnull, warn_unused_result))

1626

1683

error_t bring_up_interface(const char *const interface,

1627

1684

const float delay){

1628

int sd = -1;

1629

1685

error_t old_errno = errno;

1630

error_t ret_errno = 0;

1631

int ret, ret_setflags;

1686

int ret;

1632

1687

struct ifreq network;

1633

1688

unsigned int if_index = if_nametoindex(interface);

1634

1689

if(if_index == 0){

1643

1698

}

1644

1699

1645

1700

if(not interface_is_up(interface)){

1646

if(not get_flags(interface, &network) and debug){

1701

error_t ret_errno = 0, ioctl_errno = 0;

1702

if(not get_flags(interface, &network)){

1647

1703

ret_errno = errno;

1648

1704

fprintf_plus(stderr, "Failed to get flags for interface "

1649

1705

"\"%s\"\n", interface);

1706

errno = old_errno;

1650

1707

return ret_errno;

1651

1708

}

1652

network.ifr_flags |= IFF_UP;

1709

network.ifr_flags |= IFF_UP; /* set flag */

1653

1710

1654

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1655

if(sd < 0){

1711

int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1712

if(sd == -1){

1656

1713

ret_errno = errno;

1657

1714

perror_plus("socket");

1658

1715

errno = old_errno;

1659

1716

return ret_errno;

1660

1717

}

1661

1718

1662

1719

if(quit_now){

1663

close(sd);

1720

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

1721

if(ret == -1){

1722

perror_plus("close");

1723

}

1664

1724

errno = old_errno;

1665

1725

return EINTR;

1666

1726

}

1670

1730

interface);

1671

1731

}

1672

1732

1673

/* Raise priviliges */

1674

raise_privileges();

1733

/* Raise privileges */

1734

ret_errno = raise_privileges();

1735

if(ret_errno != 0){

1736

errno = ret_errno;

1737

perror_plus("Failed to raise privileges");

1738

}

1675

1739

1676

1740

#ifdef __linux__

1677

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1678

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

1679

int ret_linux = klogctl(8, NULL, 5);

1680

bool restore_loglevel = true;

1681

if(ret_linux == -1){

1682

restore_loglevel = false;

1683

perror_plus("klogctl");

1741

int ret_linux;

1742

bool restore_loglevel = false;

1743

if(ret_errno == 0){

1744

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1745

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

1746

ret_linux = klogctl(8, NULL, 5);

1747

if(ret_linux == -1){

1748

perror_plus("klogctl");

1749

} else {

1750

restore_loglevel = true;

1751

}

1684

1752

}

1685

1753

#endif /* __linux__ */

1686

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

1687

ret_errno = errno;

1754

int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);

1755

ioctl_errno = errno;

1688

1756

#ifdef __linux__

1689

1757

if(restore_loglevel){

1690

1758

ret_linux = klogctl(7, NULL, 0);

1694

1762

}

1695

1763

#endif /* __linux__ */

1696

1764

1697

/* Lower privileges */

1698

lower_privileges();

1765

/* If raise_privileges() succeeded above */

1766

if(ret_errno == 0){

1767

/* Lower privileges */

1768

ret_errno = lower_privileges();

1769

if(ret_errno != 0){

1770

errno = ret_errno;

1771

perror_plus("Failed to lower privileges");

1772

}

1773

}

1699

1774

1700

1775

/* Close the socket */

1701

1776

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

1704

1779

}

1705

1780

1706

1781

if(ret_setflags == -1){

1707

errno = ret_errno;

1782

errno = ioctl_errno;

1708

1783

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1709

1784

errno = old_errno;

1710

return ret_errno;

1785

return ioctl_errno;

1711

1786

}

1712

1787

} else if(debug){

1713

1788

fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",

1731

1806

return 0;

1732

1807

}

1733

1808

1809

__attribute__((nonnull, warn_unused_result))

1734

1810

error_t take_down_interface(const char *const interface){

1735

1811

error_t old_errno = errno;

1736

1812

struct ifreq network;

1741

1817

return ENXIO;

1742

1818

}

1743

1819

if(interface_is_up(interface)){

1744

error_t ret_errno = 0;

1820

error_t ret_errno = 0, ioctl_errno = 0;

1745

1821

if(not get_flags(interface, &network) and debug){

1746

1822

ret_errno = errno;

1747

1823

fprintf_plus(stderr, "Failed to get flags for interface "

1748

1824

"\"%s\"\n", interface);

1825

errno = old_errno;

1749

1826

return ret_errno;

1750

1827

}

1751

1828

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

1752

1829

1753

1830

int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1754

if(sd < 0){

1831

if(sd == -1){

1755

1832

ret_errno = errno;

1756

1833

perror_plus("socket");

1757

1834

errno = old_errno;

1763

1840

interface);

1764

1841

}

1765

1842

1766

/* Raise priviliges */

1767

raise_privileges();

1843

/* Raise privileges */

1844

ret_errno = raise_privileges();

1845

if(ret_errno != 0){

1846

errno = ret_errno;

1847

perror_plus("Failed to raise privileges");

1848

}

1768

1849

1769

1850

int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);

1770

ret_errno = errno;

1851

ioctl_errno = errno;

1771

1852

1772

/* Lower privileges */

1773

lower_privileges();

1853

/* If raise_privileges() succeeded above */

1854

if(ret_errno == 0){

1855

/* Lower privileges */

1856

ret_errno = lower_privileges();

1857

if(ret_errno != 0){

1858

errno = ret_errno;

1859

perror_plus("Failed to lower privileges");

1860

}

1861

}

1774

1862

1775

1863

/* Close the socket */

1776

1864

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

1779

1867

}

1780

1868

1781

1869

if(ret_setflags == -1){

1782

errno = ret_errno;

1870

errno = ioctl_errno;

1783

1871

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1784

1872

errno = old_errno;

1785

return ret_errno;

1873

return ioctl_errno;

1786

1874

}

1787

1875

} else if(debug){

1788

1876

fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",

1796

1884

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

1797

1885

mandos_context mc = { .server = NULL, .dh_bits = 1024,

1798

1886

.priority = "SECURE256:!CTYPE-X.509:"

1799

"+CTYPE-OPENPGP", .current_server = NULL,

1887

"+CTYPE-OPENPGP", .current_server = NULL,

1800

1888

.interfaces = NULL, .interfaces_size = 0 };

1801

1889

AvahiSServiceBrowser *sb = NULL;

1802

1890

error_t ret_errno;

1806

1894

int exitcode = EXIT_SUCCESS;

1807

1895

char *interfaces_to_take_down = NULL;

1808

1896

size_t interfaces_to_take_down_size = 0;

1809

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

1810

bool tempdir_created = false;

1897

char run_tempdir[] = "/run/tmp/mandosXXXXXX";

1898

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

1899

char *tempdir = NULL;

1811

1900

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1812

1901

const char *seckey = PATHDIR "/" SECKEY;

1813

1902

const char *pubkey = PATHDIR "/" PUBKEY;

1995

2084

/* Work around Debian bug #633582:

1996

2085

<http://bugs.debian.org/633582> */

1997

2086

1998

/* Re-raise priviliges */

1999

if(raise_privileges() == 0){

2087

/* Re-raise privileges */

2088

ret_errno = raise_privileges();

2089

if(ret_errno != 0){

2090

errno = ret_errno;

2091

perror_plus("Failed to raise privileges");

2092

} else {

2000

2093

struct stat st;

2001

2094

2002

2095

if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){

2042

2135

}

2043

2136

2044

2137

/* Lower privileges */

2045

lower_privileges();

2138

ret_errno = lower_privileges();

2139

if(ret_errno != 0){

2140

errno = ret_errno;

2141

perror_plus("Failed to lower privileges");

2142

}

2046

2143

}

2047

2144

}

2048

2145

2074

2171

memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);

2075

2172

argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');

2076

2173

}

2077

if(not run_network_hooks("start", interfaces_hooks != NULL ?

2078

interfaces_hooks : "", delay)){

2079

goto end;

2080

}

2174

run_network_hooks("start", interfaces_hooks != NULL ?

2175

interfaces_hooks : "", delay);

2081

2176

}

2082

2177

2083

2178

if(not debug){

2161

2256

2162

2257

/* If no interfaces were specified, make a list */

2163

2258

if(mc.interfaces == NULL){

2164

struct dirent **direntries;

2259

struct dirent **direntries = NULL;

2165

2260

/* Look for any good interfaces */

2166

2261

ret = scandir(sys_class_net, &direntries, good_interface,

2167

2262

alphasort);

2182

2277

}

2183

2278

free(direntries);

2184

2279

} else {

2185

free(direntries);

2280

if(ret == 0){

2281

free(direntries);

2282

}

2186

2283

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

2187

2284

exitcode = EXIT_FAILURE;

2188

2285

goto end;

2211

2308

break;

2212

2309

}

2213

2310

bool interface_was_up = interface_is_up(interface);

2214

ret = bring_up_interface(interface, delay);

2311

errno = bring_up_interface(interface, delay);

2215

2312

if(not interface_was_up){

2216

if(ret != 0){

2217

errno = ret;

2313

if(errno != 0){

2218

2314

perror_plus("Failed to bring up interface");

2219

2315

} else {

2220

ret_errno = argz_add(&interfaces_to_take_down,

2221

&interfaces_to_take_down_size,

2222

interface);

2223

if(ret_errno != 0){

2224

errno = ret_errno;

2316

errno = argz_add(&interfaces_to_take_down,

2317

&interfaces_to_take_down_size,

2318

interface);

2319

if(errno != 0){

2225

2320

perror_plus("argz_add");

2226

2321

}

2227

2322

}

2258

2353

goto end;

2259

2354

}

2260

2355

2261

if(mkdtemp(tempdir) == NULL){

2356

/* Try /run/tmp before /tmp */

2357

tempdir = mkdtemp(run_tempdir);

2358

if(tempdir == NULL and errno == ENOENT){

2359

if(debug){

2360

fprintf_plus(stderr, "Tempdir %s did not work, trying %s\n",

2361

run_tempdir, old_tempdir);

2362

}

2363

tempdir = mkdtemp(old_tempdir);

2364

}

2365

if(tempdir == NULL){

2262

2366

perror_plus("mkdtemp");

2263

2367

goto end;

2264

2368

}

2265

tempdir_created = true;

2266

2369

2267

2370

if(quit_now){

2268

2371

goto end;

2343

2446

sleep((unsigned int)retry_interval);

2344

2447

}

2345

2448

2346

if (not quit_now){

2449

if(not quit_now){

2347

2450

exitcode = EXIT_SUCCESS;

2348

2451

}

2349

2452

2404

2507

if(debug){

2405

2508

fprintf_plus(stderr, "Starting Avahi loop search\n");

2406

2509

}

2407

2510

2408

2511

ret = avahi_loop_with_timeout(simple_poll,

2409

2512

(int)(retry_interval * 1000), &mc);

2410

2513

if(debug){

2451

2554

}

2452

2555

}

2453

2556

2454

/* Re-raise priviliges */

2557

/* Re-raise privileges */

2455

2558

{

2456

raise_privileges();

2457

2458

/* Run network hooks */

2459

run_network_hooks("stop", interfaces_hooks != NULL ?

2460

interfaces_hooks : "", delay);

2461

2462

/* Take down the network interfaces which were brought up */

2463

{

2464

char *interface = NULL;

2465

while((interface=argz_next(interfaces_to_take_down,

2466

interfaces_to_take_down_size,

2467

interface))){

2468

ret_errno = take_down_interface(interface);

2469

if(ret_errno != 0){

2470

errno = ret_errno;

2471

perror_plus("Failed to take down interface");

2472

}

2473

}

2474

if(debug and (interfaces_to_take_down == NULL)){

2475

fprintf_plus(stderr, "No interfaces needed to be taken"

2476

" down\n");

2477

}

2478

}

2479

2480

lower_privileges_permanently();

2559

ret_errno = raise_privileges();

2560

if(ret_errno != 0){

2561

errno = ret_errno;

2562

perror_plus("Failed to raise privileges");

2563

} else {

2564

2565

/* Run network hooks */

2566

run_network_hooks("stop", interfaces_hooks != NULL ?

2567

interfaces_hooks : "", delay);

2568

2569

/* Take down the network interfaces which were brought up */

2570

{

2571

char *interface = NULL;

2572

while((interface=argz_next(interfaces_to_take_down,

2573

interfaces_to_take_down_size,

2574

interface))){

2575

ret_errno = take_down_interface(interface);

2576

if(ret_errno != 0){

2577

errno = ret_errno;

2578

perror_plus("Failed to take down interface");

2579

}

2580

}

2581

if(debug and (interfaces_to_take_down == NULL)){

2582

fprintf_plus(stderr, "No interfaces needed to be taken"

2583

" down\n");

2584

}

2585

}

2586

}

2587

2588

ret_errno = lower_privileges_permanently();

2589

if(ret_errno != 0){

2590

errno = ret_errno;

2591

perror_plus("Failed to lower privileges permanently");

2592

}

2481

2593

}

2482

2594

2483

2595

free(interfaces_to_take_down);

2484

2596

free(interfaces_hooks);

2485

2597

2486

2598

/* Removes the GPGME temp directory and all files inside */

2487

if(tempdir_created){

2599

if(tempdir != NULL){

2488

2600

struct dirent **direntries = NULL;

2489

struct dirent *direntry = NULL;

2490

int numentries = scandir(tempdir, &direntries, notdotentries,

2491

alphasort);

2492

if (numentries > 0){

2493

for(int i = 0; i < numentries; i++){

2494

direntry = direntries[i];

2495

char *fullname = NULL;

2496

ret = asprintf(&fullname, "%s/%s", tempdir,

2497

direntry->d_name);

2498

if(ret < 0){

2499

perror_plus("asprintf");

2500

continue;

2501

}

2502

ret = remove(fullname);

2503

if(ret == -1){

2504

fprintf_plus(stderr, "remove(\"%s\"): %s\n", fullname,

2505

strerror(errno));

2506

}

2507

free(fullname);

2601

int tempdir_fd = (int)TEMP_FAILURE_RETRY(open(tempdir, O_RDONLY |

2602

O_NOFOLLOW));

2603

if(tempdir_fd == -1){

2604

perror_plus("open");

2605

} else {

2606

#ifdef __GLIBC__

2607

#if __GLIBC_PREREQ(2, 15)

2608

int numentries = scandirat(tempdir_fd, ".", &direntries,

2609

notdotentries, alphasort);

2610

#else /* not __GLIBC_PREREQ(2, 15) */

2611

int numentries = scandir(tempdir, &direntries, notdotentries,

2612

alphasort);

2613

#endif /* not __GLIBC_PREREQ(2, 15) */

2614

#else /* not __GLIBC__ */

2615

int numentries = scandir(tempdir, &direntries, notdotentries,

2616

alphasort);

2617

#endif /* not __GLIBC__ */

2618

if(numentries >= 0){

2619

for(int i = 0; i < numentries; i++){

2620

ret = unlinkat(tempdir_fd, direntries[i]->d_name, 0);

2621

if(ret == -1){

2622

fprintf_plus(stderr, "unlinkat(open(\"%s\", O_RDONLY),"

2623

" \"%s\", 0): %s\n", tempdir,

2624

direntries[i]->d_name, strerror(errno));

2625

}

2626

}

2627

2628

/* need to clean even if 0 because man page doesn't specify */

2629

free(direntries);

2630

if(numentries == -1){

2631

perror_plus("scandir");

2632

}

2633

ret = rmdir(tempdir);

2634

if(ret == -1 and errno != ENOENT){

2635

perror_plus("rmdir");

2636

}

2508

2637

}

2509

}

2510

2511

/* need to clean even if 0 because man page doesn't specify */

2512

free(direntries);

2513

if (numentries == -1){

2514

perror_plus("scandir");

2515

}

2516

ret = rmdir(tempdir);

2517

if(ret == -1 and errno != ENOENT){

2518

perror_plus("rmdir");

2638

TEMP_FAILURE_RETRY(close(tempdir_fd));

2519

2639

}

2520

2640

}

2521

2641