/mandos/trunk : revision 742

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(),

57

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

58

inet_pton(), connect(),

59

getnameinfo() */

60

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

60

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

61

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

62

*/

63

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

73

*/

74

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

75

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

76

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

76

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

77

unlinkat() */

77

78

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

78

79

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

79

80

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

141

142

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

142

143

char *connect_to = NULL;

143

144

const char *hookdir = HOOKDIR;

145

int hookdir_fd = -1;

144

146

uid_t uid = 65534;

145

147

gid_t gid = 65534;

146

148

183

185

perror(print_text);

184

186

}

185

187

186

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

188

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

187

189

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

188

190

va_list ap;

189

191

va_start (ap, format);

198

200

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

199

201

* "buffer_length" is how much is already used.

200

202

*/

203

__attribute__((nonnull, warn_unused_result))

201

204

size_t incbuffer(char **buffer, size_t buffer_length,

202

205

size_t buffer_capacity){

203

206

if(buffer_length + BUFFER_SIZE > buffer_capacity){

216

219

}

217

220

218

221

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

222

__attribute__((nonnull, warn_unused_result))

219

223

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

220

224

int af, server **current_server){

221

225

int ret;

230

234

.af = af };

231

235

if(new_server->ip == NULL){

232

236

perror_plus("strdup");

237

free(new_server);

233

238

return false;

234

239

}

235

240

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

236

241

if(ret == -1){

237

242

perror_plus("clock_gettime");

243

#ifdef __GNUC__

244

#pragma GCC diagnostic push

245

#pragma GCC diagnostic ignored "-Wcast-qual"

246

#endif

247

free((char *)(new_server->ip));

248

#ifdef __GNUC__

249

#pragma GCC diagnostic pop

250

#endif

251

free(new_server);

238

252

return false;

239

253

}

240

254

/* Special case of first server */

242

256

new_server->next = new_server;

243

257

new_server->prev = new_server;

244

258

*current_server = new_server;

245

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

246

259

} else {

260

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

247

261

new_server->next = *current_server;

248

262

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

249

263

new_server->prev->next = new_server;

255

269

/*

256

270

* Initialize GPGME.

257

271

*/

258

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

259

const char *tempdir, mandos_context *mc){

272

__attribute__((nonnull, warn_unused_result))

273

static bool init_gpgme(const char * const seckey,

274

const char * const pubkey,

275

const char * const tempdir,

276

mandos_context *mc){

260

277

gpgme_error_t rc;

261

278

gpgme_engine_info_t engine_info;

262

279

263

280

/*

264

281

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

265

282

*/

266

bool import_key(const char *filename){

283

bool import_key(const char * const filename){

267

284

int ret;

268

285

int fd;

269

286

gpgme_data_t pgp_data;

350

367

* Decrypt OpenPGP data.

351

368

* Returns -1 on error

352

369

*/

370

__attribute__((nonnull, warn_unused_result))

353

371

static ssize_t pgp_packet_decrypt(const char *cryptotext,

354

372

size_t crypto_size,

355

373

char **plaintext,

475

493

return plaintext_length;

476

494

}

477

495

478

static const char * safer_gnutls_strerror(int value){

496

__attribute__((warn_unused_result))

497

static const char *safer_gnutls_strerror(int value){

479

498

const char *ret = gnutls_strerror(value);

480

499

if(ret == NULL)

481

500

ret = "(unknown)";

483

502

}

484

503

485

504

/* GnuTLS log function callback */

505

__attribute__((nonnull))

486

506

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

487

507

const char* string){

488

508

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

489

509

}

490

510

511

__attribute__((nonnull, warn_unused_result))

491

512

static int init_gnutls_global(const char *pubkeyfilename,

492

513

const char *seckeyfilename,

493

514

mandos_context *mc){

567

588

return -1;

568

589

}

569

590

591

__attribute__((nonnull, warn_unused_result))

570

592

static int init_gnutls_session(gnutls_session_t *session,

571

593

mandos_context *mc){

572

594

int ret;

629

651

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

630

652

631

653

/* Called when a Mandos server is found */

654

__attribute__((nonnull, warn_unused_result))

632

655

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

633

656

AvahiIfIndex if_index,

634

657

int af, mandos_context *mc){

740

763

goto mandos_end;

741

764

}

742

765

if(af == AF_INET6){

743

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

766

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

744

767

if(IN6_IS_ADDR_LINKLOCAL

745

768

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

746

769

if(if_index == AVAHI_IF_UNSPEC){

809

832

sizeof(struct sockaddr_in));

810

833

}

811

834

if(ret < 0){

812

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

835

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

813

836

int e = errno;

814

837

perror_plus("connect");

815

838

errno = e;

1030

1053

return retval;

1031

1054

}

1032

1055

1056

__attribute__((nonnull))

1033

1057

static void resolve_callback(AvahiSServiceResolver *r,

1034

1058

AvahiIfIndex interface,

1035

1059

AvahiProtocol proto,

1043

1067

AVAHI_GCC_UNUSED AvahiStringList *txt,

1044

1068

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1045

1069

flags,

1046

void* mc){

1070

void *mc){

1047

1071

if(r == NULL){

1048

1072

return;

1049

1073

}

1052

1076

timed out */

1053

1077

1054

1078

if(quit_now){

1079

avahi_s_service_resolver_free(r);

1055

1080

return;

1056

1081

}

1057

1082

1102

1127

const char *domain,

1103

1128

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1104

1129

flags,

1105

void* mc){

1130

void *mc){

1106

1131

if(b == NULL){

1107

1132

return;

1108

1133

}

1168

1193

errno = old_errno;

1169

1194

}

1170

1195

1196

__attribute__((nonnull, warn_unused_result))

1171

1197

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

1172

1198

int ret;

1173

1199

error_t ret_errno;

1192

1218

return true;

1193

1219

}

1194

1220

1221

__attribute__((nonnull, warn_unused_result))

1195

1222

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

1196

1223

1197

1224

/* Reject the loopback device */

1239

1266

* corresponds to an acceptable network device.

1240

1267

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

1241

1268

*/

1269

__attribute__((nonnull, warn_unused_result))

1242

1270

int good_interface(const struct dirent *if_entry){

1243

1271

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

1244

1272

return 0;

1262

1290

/*

1263

1291

* This function determines if a network interface is up.

1264

1292

*/

1293

__attribute__((nonnull, warn_unused_result))

1265

1294

bool interface_is_up(const char *interface){

1266

1295

struct ifreq ifr;

1267

1296

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

1278

1307

/*

1279

1308

* This function determines if a network interface is running

1280

1309

*/

1310

__attribute__((nonnull, warn_unused_result))

1281

1311

bool interface_is_running(const char *interface){

1282

1312

struct ifreq ifr;

1283

1313

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

1291

1321

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

1292

1322

}

1293

1323

1324

__attribute__((nonnull, pure, warn_unused_result))

1294

1325

int notdotentries(const struct dirent *direntry){

1295

1326

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

1296

1327

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

1303

1334

}

1304

1335

1305

1336

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

1337

__attribute__((nonnull, warn_unused_result))

1306

1338

int runnable_hook(const struct dirent *direntry){

1307

1339

int ret;

1308

1340

size_t sret;

1316

1348

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

1317

1349

"abcdefghijklmnopqrstuvwxyz"

1318

1350

"0123456789"

1319

"_-");

1351

"_.-");

1320

1352

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

1321

1353

/* Contains non-allowed characters */

1322

1354

if(debug){

1326

1358

return 0;

1327

1359

}

1328

1360

1329

char *fullname = NULL;

1330

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

1331

if(ret < 0){

1332

perror_plus("asprintf");

1333

return 0;

1334

}

1335

1336

ret = stat(fullname, &st);

1361

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

1337

1362

if(ret == -1){

1338

1363

if(debug){

1339

1364

perror_plus("Could not stat hook");

1363

1388

return 1;

1364

1389

}

1365

1390

1391

__attribute__((nonnull, warn_unused_result))

1366

1392

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1367

1393

mandos_context *mc){

1368

1394

int ret;

1372

1398

1373

1399

while(true){

1374

1400

if(mc->current_server == NULL){

1375

if (debug){

1401

if(debug){

1376

1402

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

1377

1403

" No timeout!\n");

1378

1404

}

1379

1405

ret = avahi_simple_poll_iterate(s, -1);

1380

1406

} else {

1381

if (debug){

1407

if(debug){

1382

1408

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

1383

1409

" it, or wait\n");

1384

1410

}

1401

1427

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

1402

1428

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

1403

1429

1404

if (debug){

1430

if(debug){

1405

1431

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

1406

1432

block_time);

1407

1433

}

1429

1455

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

1430

1456

}

1431

1457

if(ret != 0){

1432

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

1458

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

1433

1459

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

1434

1460

}

1435

1461

}

1437

1463

}

1438

1464

1439

1465

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

1466

__attribute__((warn_unused_result))

1440

1467

error_t raise_privileges(void){

1441

1468

error_t old_errno = errno;

1442

1469

error_t ret_errno = 0;

1443

1470

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

1444

1471

ret_errno = errno;

1445

perror_plus("seteuid");

1446

1472

}

1447

1473

errno = old_errno;

1448

1474

return ret_errno;

1449

1475

}

1450

1476

1451

1477

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

1478

__attribute__((warn_unused_result))

1452

1479

error_t raise_privileges_permanently(void){

1453

1480

error_t old_errno = errno;

1454

1481

error_t ret_errno = raise_privileges();

1458

1485

}

1459

1486

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

1460

1487

ret_errno = errno;

1461

perror_plus("seteuid");

1462

1488

}

1463

1489

errno = old_errno;

1464

1490

return ret_errno;

1465

1491

}

1466

1492

1467

1493

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

1494

__attribute__((warn_unused_result))

1468

1495

error_t lower_privileges(void){

1469

1496

error_t old_errno = errno;

1470

1497

error_t ret_errno = 0;

1471

1498

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

1472

1499

ret_errno = errno;

1473

perror_plus("seteuid");

1474

1500

}

1475

1501

errno = old_errno;

1476

1502

return ret_errno;

1477

1503

}

1478

1504

1479

1505

/* Lower privileges permanently */

1506

__attribute__((warn_unused_result))

1480

1507

error_t lower_privileges_permanently(void){

1481

1508

error_t old_errno = errno;

1482

1509

error_t ret_errno = 0;

1483

1510

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

1484

1511

ret_errno = errno;

1485

perror_plus("setuid");

1486

1512

}

1487

1513

errno = old_errno;

1488

1514

return ret_errno;

1489

1515

}

1490

1516

1491

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

1517

__attribute__((nonnull))

1518

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

1492

1519

const float delay){

1493

struct dirent **direntries;

1494

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

1495

alphasort);

1520

struct dirent **direntries = NULL;

1521

if(hookdir_fd == -1){

1522

hookdir_fd = open(hookdir, O_RDONLY);

1523

if(hookdir_fd == -1){

1524

if(errno == ENOENT){

1525

if(debug){

1526

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

1527

" found\n", hookdir);

1528

}

1529

} else {

1530

perror_plus("open");

1531

}

1532

return;

1533

}

1534

}

1535

#ifdef __GLIBC__

1536

#if __GLIBC_PREREQ(2, 15)

1537

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

1538

runnable_hook, alphasort);

1539

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

1540

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

1541

alphasort);

1542

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

1543

#else /* not __GLIBC__ */

1544

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

1545

alphasort);

1546

#endif /* not __GLIBC__ */

1496

1547

if(numhooks == -1){

1497

if(errno == ENOENT){

1498

if(debug){

1499

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

1500

" found\n", hookdir);

1501

}

1502

} else {

1503

perror_plus("scandir");

1548

perror_plus("scandir");

1549

return;

1550

}

1551

struct dirent *direntry;

1552

int ret;

1553

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

1554

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

1555

direntry = direntries[i];

1556

if(debug){

1557

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

1558

direntry->d_name);

1504

1559

}

1505

} else {

1506

struct dirent *direntry;

1507

int ret;

1508

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

1509

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

1510

direntry = direntries[i];

1511

char *fullname = NULL;

1512

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

1513

if(ret < 0){

1560

pid_t hook_pid = fork();

1561

if(hook_pid == 0){

1562

/* Child */

1563

/* Raise privileges */

1564

errno = raise_privileges_permanently();

1565

if(errno != 0){

1566

perror_plus("Failed to raise privileges");

1567

_exit(EX_NOPERM);

1568

}

1569

/* Set group */

1570

errno = 0;

1571

ret = setgid(0);

1572

if(ret == -1){

1573

perror_plus("setgid");

1574

_exit(EX_NOPERM);

1575

}

1576

/* Reset supplementary groups */

1577

errno = 0;

1578

ret = setgroups(0, NULL);

1579

if(ret == -1){

1580

perror_plus("setgroups");

1581

_exit(EX_NOPERM);

1582

}

1583

ret = dup2(devnull, STDIN_FILENO);

1584

if(ret == -1){

1585

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

1586

_exit(EX_OSERR);

1587

}

1588

ret = close(devnull);

1589

if(ret == -1){

1590

perror_plus("close");

1591

_exit(EX_OSERR);

1592

}

1593

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1594

if(ret == -1){

1595

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

1596

_exit(EX_OSERR);

1597

}

1598

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

1599

if(ret == -1){

1600

perror_plus("setenv");

1601

_exit(EX_OSERR);

1602

}

1603

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

1604

if(ret == -1){

1605

perror_plus("setenv");

1606

_exit(EX_OSERR);

1607

}

1608

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

1609

if(ret == -1){

1610

perror_plus("setenv");

1611

_exit(EX_OSERR);

1612

}

1613

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

1614

if(ret == -1){

1615

perror_plus("setenv");

1616

_exit(EX_OSERR);

1617

}

1618

char *delaystring;

1619

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

1620

if(ret == -1){

1514

1621

perror_plus("asprintf");

1515

continue;

1516

}

1517

if(debug){

1518

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

1519

direntry->d_name);

1520

}

1521

pid_t hook_pid = fork();

1522

if(hook_pid == 0){

1523

/* Child */

1524

/* Raise privileges */

1525

raise_privileges_permanently();

1526

/* Set group */

1527

errno = 0;

1528

ret = setgid(0);

1529

if(ret == -1){

1530

perror_plus("setgid");

1531

}

1532

/* Reset supplementary groups */

1533

errno = 0;

1534

ret = setgroups(0, NULL);

1535

if(ret == -1){

1536

perror_plus("setgroups");

1537

}

1538

dup2(devnull, STDIN_FILENO);

1539

close(devnull);

1540

dup2(STDERR_FILENO, STDOUT_FILENO);

1541

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

1542

if(ret == -1){

1543

perror_plus("setenv");

1544

_exit(EX_OSERR);

1545

}

1546

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

1547

if(ret == -1){

1548

perror_plus("setenv");

1549

_exit(EX_OSERR);

1550

}

1551

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

1552

if(ret == -1){

1553

perror_plus("setenv");

1554

_exit(EX_OSERR);

1555

}

1556

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

1557

if(ret == -1){

1558

perror_plus("setenv");

1559

_exit(EX_OSERR);

1560

}

1561

char *delaystring;

1562

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

1563

if(ret == -1){

1564

perror_plus("asprintf");

1565

_exit(EX_OSERR);

1566

}

1567

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

1568

if(ret == -1){

1569

free(delaystring);

1570

perror_plus("setenv");

1571

_exit(EX_OSERR);

1572

}

1622

_exit(EX_OSERR);

1623

}

1624

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

1625

if(ret == -1){

1573

1626

free(delaystring);

1574

if(connect_to != NULL){

1575

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

1576

if(ret == -1){

1577

perror_plus("setenv");

1578

_exit(EX_OSERR);

1579

}

1580

}

1581

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

1582

perror_plus("execl");

1583

_exit(EXIT_FAILURE);

1584

}

1627

perror_plus("setenv");

1628

_exit(EX_OSERR);

1629

}

1630

free(delaystring);

1631

if(connect_to != NULL){

1632

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

1633

if(ret == -1){

1634

perror_plus("setenv");

1635

_exit(EX_OSERR);

1636

}

1637

}

1638

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

1639

if(hook_fd == -1){

1640

perror_plus("openat");

1641

_exit(EXIT_FAILURE);

1642

}

1643

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

1644

perror_plus("close");

1645

_exit(EXIT_FAILURE);

1646

}

1647

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

1648

environ) == -1){

1649

perror_plus("fexecve");

1650

_exit(EXIT_FAILURE);

1651

}

1652

} else {

1653

if(hook_pid == -1){

1654

perror_plus("fork");

1655

free(direntry);

1656

continue;

1657

}

1658

int status;

1659

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

1660

perror_plus("waitpid");

1661

free(direntry);

1662

continue;

1663

}

1664

if(WIFEXITED(status)){

1665

if(WEXITSTATUS(status) != 0){

1666

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

1667

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

1668

WEXITSTATUS(status));

1669

free(direntry);

1670

continue;

1671

}

1672

} else if(WIFSIGNALED(status)){

1673

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

1674

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

1675

WTERMSIG(status));

1676

free(direntry);

1677

continue;

1585

1678

} else {

1586

int status;

1587

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

1588

perror_plus("waitpid");

1589

free(fullname);

1590

continue;

1591

}

1592

if(WIFEXITED(status)){

1593

if(WEXITSTATUS(status) != 0){

1594

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

1595

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

1596

WEXITSTATUS(status));

1597

free(fullname);

1598

continue;

1599

}

1600

} else if(WIFSIGNALED(status)){

1601

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

1602

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

1603

WTERMSIG(status));

1604

free(fullname);

1605

continue;

1606

} else {

1607

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

1608

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

1609

free(fullname);

1610

continue;

1611

}

1612

}

1613

free(fullname);

1614

if(debug){

1615

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

1616

direntry->d_name);

1617

}

1618

}

1619

close(devnull);

1620

}

1621

return true;

1679

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

1680

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

1681

free(direntry);

1682

continue;

1683

}

1684

}

1685

if(debug){

1686

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

1687

direntry->d_name);

1688

}

1689

free(direntry);

1690

}

1691

free(direntries);

1692

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

1693

perror_plus("close");

1694

} else {

1695

hookdir_fd = -1;

1696

}

1697

close(devnull);

1622

1698

}

1623

1699

1700

__attribute__((nonnull, warn_unused_result))

1624

1701

error_t bring_up_interface(const char *const interface,

1625

1702

const float delay){

1626

int sd = -1;

1627

1703

error_t old_errno = errno;

1628

error_t ret_errno = 0;

1629

int ret, ret_setflags;

1704

int ret;

1630

1705

struct ifreq network;

1631

1706

unsigned int if_index = if_nametoindex(interface);

1632

1707

if(if_index == 0){

1641

1716

}

1642

1717

1643

1718

if(not interface_is_up(interface)){

1644

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

1719

error_t ret_errno = 0, ioctl_errno = 0;

1720

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

1645

1721

ret_errno = errno;

1646

1722

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

1647

1723

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

1724

errno = old_errno;

1648

1725

return ret_errno;

1649

1726

}

1650

network.ifr_flags |= IFF_UP;

1727

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

1651

1728

1652

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1653

if(sd < 0){

1729

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

1730

if(sd == -1){

1654

1731

ret_errno = errno;

1655

1732

perror_plus("socket");

1656

1733

errno = old_errno;

1657

1734

return ret_errno;

1658

1735

}

1659

1736

1660

1737

if(quit_now){

1661

close(sd);

1738

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

1739

if(ret == -1){

1740

perror_plus("close");

1741

}

1662

1742

errno = old_errno;

1663

1743

return EINTR;

1664

1744

}

1668

1748

interface);

1669

1749

}

1670

1750

1671

/* Raise priviliges */

1672

raise_privileges();

1751

/* Raise privileges */

1752

ret_errno = raise_privileges();

1753

if(ret_errno != 0){

1754

errno = ret_errno;

1755

perror_plus("Failed to raise privileges");

1756

}

1673

1757

1674

1758

#ifdef __linux__

1675

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1676

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

1677

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

1678

bool restore_loglevel = true;

1679

if(ret_linux == -1){

1680

restore_loglevel = false;

1681

perror_plus("klogctl");

1759

int ret_linux;

1760

bool restore_loglevel = false;

1761

if(ret_errno == 0){

1762

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1763

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

1764

ret_linux = klogctl(8, NULL, 5);

1765

if(ret_linux == -1){

1766

perror_plus("klogctl");

1767

} else {

1768

restore_loglevel = true;

1769

}

1682

1770

}

1683

1771

#endif /* __linux__ */

1684

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

1685

ret_errno = errno;

1772

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

1773

ioctl_errno = errno;

1686

1774

#ifdef __linux__

1687

1775

if(restore_loglevel){

1688

1776

ret_linux = klogctl(7, NULL, 0);

1692

1780

}

1693

1781

#endif /* __linux__ */

1694

1782

1695

/* Lower privileges */

1696

lower_privileges();

1783

/* If raise_privileges() succeeded above */

1784

if(ret_errno == 0){

1785

/* Lower privileges */

1786

ret_errno = lower_privileges();

1787

if(ret_errno != 0){

1788

errno = ret_errno;

1789

perror_plus("Failed to lower privileges");

1790

}

1791

}

1697

1792

1698

1793

/* Close the socket */

1699

1794

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

1702

1797

}

1703

1798

1704

1799

if(ret_setflags == -1){

1705

errno = ret_errno;

1800

errno = ioctl_errno;

1706

1801

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1707

1802

errno = old_errno;

1708

return ret_errno;

1803

return ioctl_errno;

1709

1804

}

1710

1805

} else if(debug){

1711

1806

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

1729

1824

return 0;

1730

1825

}

1731

1826

1827

__attribute__((nonnull, warn_unused_result))

1732

1828

error_t take_down_interface(const char *const interface){

1733

1829

error_t old_errno = errno;

1734

1830

struct ifreq network;

1739

1835

return ENXIO;

1740

1836

}

1741

1837

if(interface_is_up(interface)){

1742

error_t ret_errno = 0;

1838

error_t ret_errno = 0, ioctl_errno = 0;

1743

1839

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

1744

1840

ret_errno = errno;

1745

1841

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

1746

1842

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

1843

errno = old_errno;

1747

1844

return ret_errno;

1748

1845

}

1749

1846

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

1750

1847

1751

1848

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

1752

if(sd < 0){

1849

if(sd == -1){

1753

1850

ret_errno = errno;

1754

1851

perror_plus("socket");

1755

1852

errno = old_errno;

1761

1858

interface);

1762

1859

}

1763

1860

1764

/* Raise priviliges */

1765

raise_privileges();

1861

/* Raise privileges */

1862

ret_errno = raise_privileges();

1863

if(ret_errno != 0){

1864

errno = ret_errno;

1865

perror_plus("Failed to raise privileges");

1866

}

1766

1867

1767

1868

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

1768

ret_errno = errno;

1869

ioctl_errno = errno;

1769

1870

1770

/* Lower privileges */

1771

lower_privileges();

1871

/* If raise_privileges() succeeded above */

1872

if(ret_errno == 0){

1873

/* Lower privileges */

1874

ret_errno = lower_privileges();

1875

if(ret_errno != 0){

1876

errno = ret_errno;

1877

perror_plus("Failed to lower privileges");

1878

}

1879

}

1772

1880

1773

1881

/* Close the socket */

1774

1882

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

1777

1885

}

1778

1886

1779

1887

if(ret_setflags == -1){

1780

errno = ret_errno;

1888

errno = ioctl_errno;

1781

1889

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1782

1890

errno = old_errno;

1783

return ret_errno;

1891

return ioctl_errno;

1784

1892

}

1785

1893

} else if(debug){

1786

1894

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

1794

1902

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

1795

1903

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

1796

1904

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

1797

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

1905

"+CTYPE-OPENPGP:!RSA", .current_server = NULL,

1798

1906

.interfaces = NULL, .interfaces_size = 0 };

1799

1907

AvahiSServiceBrowser *sb = NULL;

1800

1908

error_t ret_errno;

1804

1912

int exitcode = EXIT_SUCCESS;

1805

1913

char *interfaces_to_take_down = NULL;

1806

1914

size_t interfaces_to_take_down_size = 0;

1807

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

1808

bool tempdir_created = false;

1915

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

1916

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

1917

char *tempdir = NULL;

1809

1918

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1810

1919

const char *seckey = PATHDIR "/" SECKEY;

1811

1920

const char *pubkey = PATHDIR "/" PUBKEY;

1993

2102

/* Work around Debian bug #633582:

1994

2103

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

1995

2104

1996

/* Re-raise priviliges */

1997

if(raise_privileges() == 0){

2105

/* Re-raise privileges */

2106

ret_errno = raise_privileges();

2107

if(ret_errno != 0){

2108

errno = ret_errno;

2109

perror_plus("Failed to raise privileges");

2110

} else {

1998

2111

struct stat st;

1999

2112

2000

2113

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

2040

2153

}

2041

2154

2042

2155

/* Lower privileges */

2043

lower_privileges();

2156

ret_errno = lower_privileges();

2157

if(ret_errno != 0){

2158

errno = ret_errno;

2159

perror_plus("Failed to lower privileges");

2160

}

2044

2161

}

2045

2162

}

2046

2163

2072

2189

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

2073

2190

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

2074

2191

}

2075

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

2076

interfaces_hooks : "", delay)){

2077

goto end;

2078

}

2192

run_network_hooks("start", interfaces_hooks != NULL ?

2193

interfaces_hooks : "", delay);

2079

2194

}

2080

2195

2081

2196

if(not debug){

2159

2274

2160

2275

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

2161

2276

if(mc.interfaces == NULL){

2162

struct dirent **direntries;

2277

struct dirent **direntries = NULL;

2163

2278

/* Look for any good interfaces */

2164

2279

ret = scandir(sys_class_net, &direntries, good_interface,

2165

2280

alphasort);

2171

2286

if(ret_errno != 0){

2172

2287

errno = ret_errno;

2173

2288

perror_plus("argz_add");

2289

free(direntries[i]);

2174

2290

continue;

2175

2291

}

2176

2292

if(debug){

2177

2293

fprintf_plus(stderr, "Will use interface \"%s\"\n",

2178

2294

direntries[i]->d_name);

2179

2295

}

2296

free(direntries[i]);

2180

2297

}

2181

2298

free(direntries);

2182

2299

} else {

2183

free(direntries);

2300

if(ret == 0){

2301

free(direntries);

2302

}

2184

2303

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

2185

2304

exitcode = EXIT_FAILURE;

2186

2305

goto end;

2209

2328

break;

2210

2329

}

2211

2330

bool interface_was_up = interface_is_up(interface);

2212

ret = bring_up_interface(interface, delay);

2331

errno = bring_up_interface(interface, delay);

2213

2332

if(not interface_was_up){

2214

if(ret != 0){

2215

errno = ret;

2333

if(errno != 0){

2216

2334

perror_plus("Failed to bring up interface");

2217

2335

} else {

2218

ret_errno = argz_add(&interfaces_to_take_down,

2219

&interfaces_to_take_down_size,

2220

interface);

2221

if(ret_errno != 0){

2222

errno = ret_errno;

2336

errno = argz_add(&interfaces_to_take_down,

2337

&interfaces_to_take_down_size,

2338

interface);

2339

if(errno != 0){

2223

2340

perror_plus("argz_add");

2224

2341

}

2225

2342

}

2256

2373

goto end;

2257

2374

}

2258

2375

2259

if(mkdtemp(tempdir) == NULL){

2376

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

2377

tempdir = mkdtemp(run_tempdir);

2378

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

2379

if(debug){

2380

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

2381

run_tempdir, old_tempdir);

2382

}

2383

tempdir = mkdtemp(old_tempdir);

2384

}

2385

if(tempdir == NULL){

2260

2386

perror_plus("mkdtemp");

2261

2387

goto end;

2262

2388

}

2263

tempdir_created = true;

2264

2389

2265

2390

if(quit_now){

2266

2391

goto end;

2341

2466

sleep((unsigned int)retry_interval);

2342

2467

}

2343

2468

2344

if (not quit_now){

2469

if(not quit_now){

2345

2470

exitcode = EXIT_SUCCESS;

2346

2471

}

2347

2472

2402

2527

if(debug){

2403

2528

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

2404

2529

}

2405

2530

2406

2531

ret = avahi_loop_with_timeout(simple_poll,

2407

2532

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

2408

2533

if(debug){

2444

2569

mc.current_server->prev->next = NULL;

2445

2570

while(mc.current_server != NULL){

2446

2571

server *next = mc.current_server->next;

2572

#ifdef __GNUC__

2573

#pragma GCC diagnostic push

2574

#pragma GCC diagnostic ignored "-Wcast-qual"

2575

#endif

2576

free((char *)(mc.current_server->ip));

2577

#ifdef __GNUC__

2578

#pragma GCC diagnostic pop

2579

#endif

2447

2580

free(mc.current_server);

2448

2581

mc.current_server = next;

2449

2582

}

2450

2583

}

2451

2584

2452

/* Re-raise priviliges */

2585

/* Re-raise privileges */

2453

2586

{

2454

raise_privileges();

2455

2456

/* Run network hooks */

2457

run_network_hooks("stop", interfaces_hooks != NULL ?

2458

interfaces_hooks : "", delay);

2459

2460

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

2461

{

2462

char *interface = NULL;

2463

while((interface=argz_next(interfaces_to_take_down,

2464

interfaces_to_take_down_size,

2465

interface))){

2466

ret_errno = take_down_interface(interface);

2467

if(ret_errno != 0){

2468

errno = ret_errno;

2469

perror_plus("Failed to take down interface");

2470

}

2471

}

2472

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

2473

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

2474

" down\n");

2475

}

2476

}

2477

2478

lower_privileges_permanently();

2587

ret_errno = raise_privileges();

2588

if(ret_errno != 0){

2589

errno = ret_errno;

2590

perror_plus("Failed to raise privileges");

2591

} else {

2592

2593

/* Run network hooks */

2594

run_network_hooks("stop", interfaces_hooks != NULL ?

2595

interfaces_hooks : "", delay);

2596

2597

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

2598

{

2599

char *interface = NULL;

2600

while((interface=argz_next(interfaces_to_take_down,

2601

interfaces_to_take_down_size,

2602

interface))){

2603

ret_errno = take_down_interface(interface);

2604

if(ret_errno != 0){

2605

errno = ret_errno;

2606

perror_plus("Failed to take down interface");

2607

}

2608

}

2609

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

2610

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

2611

" down\n");

2612

}

2613

}

2614

}

2615

2616

ret_errno = lower_privileges_permanently();

2617

if(ret_errno != 0){

2618

errno = ret_errno;

2619

perror_plus("Failed to lower privileges permanently");

2620

}

2479

2621

}

2480

2622

2481

2623

free(interfaces_to_take_down);

2482

2624

free(interfaces_hooks);

2483

2625

2484

2626

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

2485

if(tempdir_created){

2627

if(tempdir != NULL){

2486

2628

struct dirent **direntries = NULL;

2487

struct dirent *direntry = NULL;

2488

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

2489

alphasort);

2490

if (numentries > 0){

2491

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

2492

direntry = direntries[i];

2493

char *fullname = NULL;

2494

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

2495

direntry->d_name);

2496

if(ret < 0){

2497

perror_plus("asprintf");

2498

continue;

2499

}

2500

ret = remove(fullname);

2501

if(ret == -1){

2502

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

2503

strerror(errno));

2504

}

2505

free(fullname);

2629

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

2630

O_NOFOLLOW));

2631

if(tempdir_fd == -1){

2632

perror_plus("open");

2633

} else {

2634

#ifdef __GLIBC__

2635

#if __GLIBC_PREREQ(2, 15)

2636

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

2637

notdotentries, alphasort);

2638

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

2639

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

2640

alphasort);

2641

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

2642

#else /* not __GLIBC__ */

2643

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

2644

alphasort);

2645

#endif /* not __GLIBC__ */

2646

if(numentries >= 0){

2647

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

2648

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

2649

if(ret == -1){

2650

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

2651

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

2652

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

2653

}

2654

free(direntries[i]);

2655

}

2656

2657

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

2658

free(direntries);

2659

if(numentries == -1){

2660

perror_plus("scandir");

2661

}

2662

ret = rmdir(tempdir);

2663

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

2664

perror_plus("rmdir");

2665

}

2506

2666

}

2507

}

2508

2509

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

2510

free(direntries);

2511

if (numentries == -1){

2512

perror_plus("scandir");

2513

}

2514

ret = rmdir(tempdir);

2515

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

2516

perror_plus("rmdir");

2667

TEMP_FAILURE_RETRY(close(tempdir_fd));

2517

2668

}

2518

2669

}

2519

2670