/mandos/trunk : revision 709

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;

242

246

new_server->next = new_server;

243

247

new_server->prev = new_server;

244

248

*current_server = new_server;

245

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

246

249

} else {

250

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

247

251

new_server->next = *current_server;

248

252

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

249

253

new_server->prev->next = new_server;

255

259

/*

256

260

* Initialize GPGME.

257

261

*/

258

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

259

const char *tempdir, mandos_context *mc){

262

__attribute__((nonnull, warn_unused_result))

263

static bool init_gpgme(const char * const seckey,

264

const char * const pubkey,

265

const char * const tempdir,

266

mandos_context *mc){

260

267

gpgme_error_t rc;

261

268

gpgme_engine_info_t engine_info;

262

269

263

270

/*

264

271

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

265

272

*/

266

bool import_key(const char *filename){

273

bool import_key(const char * const filename){

267

274

int ret;

268

275

int fd;

269

276

gpgme_data_t pgp_data;

350

357

* Decrypt OpenPGP data.

351

358

* Returns -1 on error

352

359

*/

360

__attribute__((nonnull, warn_unused_result))

353

361

static ssize_t pgp_packet_decrypt(const char *cryptotext,

354

362

size_t crypto_size,

355

363

char **plaintext,

475

483

return plaintext_length;

476

484

}

477

485

478

static const char * safer_gnutls_strerror(int value){

486

__attribute__((warn_unused_result))

487

static const char *safer_gnutls_strerror(int value){

479

488

const char *ret = gnutls_strerror(value);

480

489

if(ret == NULL)

481

490

ret = "(unknown)";

483

492

}

484

493

485

494

/* GnuTLS log function callback */

495

__attribute__((nonnull))

486

496

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

487

497

const char* string){

488

498

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

489

499

}

490

500

501

__attribute__((nonnull, warn_unused_result))

491

502

static int init_gnutls_global(const char *pubkeyfilename,

492

503

const char *seckeyfilename,

493

504

mandos_context *mc){

567

578

return -1;

568

579

}

569

580

581

__attribute__((nonnull, warn_unused_result))

570

582

static int init_gnutls_session(gnutls_session_t *session,

571

583

mandos_context *mc){

572

584

int ret;

629

641

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

630

642

631

643

/* Called when a Mandos server is found */

644

__attribute__((nonnull, warn_unused_result))

632

645

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

633

646

AvahiIfIndex if_index,

634

647

int af, mandos_context *mc){

635

648

int ret, tcp_sd = -1;

636

649

ssize_t sret;

637

union {

638

struct sockaddr_in in;

639

struct sockaddr_in6 in6;

640

} to;

650

struct sockaddr_storage to;

641

651

char *buffer = NULL;

642

652

char *decrypted_buffer = NULL;

643

653

size_t buffer_length = 0;

724

734

725

735

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

726

736

if(af == AF_INET6){

727

to.in6.sin6_family = (sa_family_t)af;

728

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

737

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

738

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

729

739

} else { /* IPv4 */

730

to.in.sin_family = (sa_family_t)af;

731

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

740

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

741

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

732

742

}

733

743

if(ret < 0 ){

734

744

int e = errno;

743

753

goto mandos_end;

744

754

}

745

755

if(af == AF_INET6){

746

to.in6.sin6_port = htons(port);

747

#ifdef __GNUC__

748

#pragma GCC diagnostic push

749

#pragma GCC diagnostic ignored "-Wstrict-aliasing"

750

#endif

751

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

752

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

753

#ifdef __GNUC__

754

#pragma GCC diagnostic pop

755

#endif

756

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

757

if(IN6_IS_ADDR_LINKLOCAL

758

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

756

759

if(if_index == AVAHI_IF_UNSPEC){

757

760

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

758

761

" incomplete without a network interface\n");

760

763

goto mandos_end;

761

764

}

762

765

/* Set the network interface number as scope */

763

to.in6.sin6_scope_id = (uint32_t)if_index;

766

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

764

767

}

765

768

} else {

766

to.in.sin_port = htons(port);

769

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

767

770

}

768

771

769

772

if(quit_now){

787

790

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

788

791

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

789

792

if(af == AF_INET6){

790

ret = getnameinfo((struct sockaddr *)&(to.in6), sizeof(to.in6),

793

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

794

sizeof(struct sockaddr_in6),

791

795

addrstr, sizeof(addrstr), NULL, 0,

792

796

NI_NUMERICHOST);

793

797

} else {

794

ret = getnameinfo((struct sockaddr *)&(to.in), sizeof(to.in),

798

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

799

sizeof(struct sockaddr_in),

795

800

addrstr, sizeof(addrstr), NULL, 0,

796

801

NI_NUMERICHOST);

797

802

}

810

815

}

811

816

812

817

if(af == AF_INET6){

813

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

818

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

819

sizeof(struct sockaddr_in6));

814

820

} else {

815

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

821

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

822

sizeof(struct sockaddr_in));

816

823

}

817

824

if(ret < 0){

818

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

825

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

819

826

int e = errno;

820

827

perror_plus("connect");

821

828

errno = e;

1036

1043

return retval;

1037

1044

}

1038

1045

1046

__attribute__((nonnull))

1039

1047

static void resolve_callback(AvahiSServiceResolver *r,

1040

1048

AvahiIfIndex interface,

1041

1049

AvahiProtocol proto,

1049

1057

AVAHI_GCC_UNUSED AvahiStringList *txt,

1050

1058

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1051

1059

flags,

1052

void* mc){

1060

void *mc){

1053

1061

if(r == NULL){

1054

1062

return;

1055

1063

}

1108

1116

const char *domain,

1109

1117

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1110

1118

flags,

1111

void* mc){

1119

void *mc){

1112

1120

if(b == NULL){

1113

1121

return;

1114

1122

}

1174

1182

errno = old_errno;

1175

1183

}

1176

1184

1185

__attribute__((nonnull, warn_unused_result))

1177

1186

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

1178

1187

int ret;

1179

1188

error_t ret_errno;

1198

1207

return true;

1199

1208

}

1200

1209

1210

__attribute__((nonnull, warn_unused_result))

1201

1211

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

1202

1212

1203

1213

/* Reject the loopback device */

1245

1255

* corresponds to an acceptable network device.

1246

1256

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

1247

1257

*/

1258

__attribute__((nonnull, warn_unused_result))

1248

1259

int good_interface(const struct dirent *if_entry){

1249

1260

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

1250

1261

return 0;

1268

1279

/*

1269

1280

* This function determines if a network interface is up.

1270

1281

*/

1282

__attribute__((nonnull, warn_unused_result))

1271

1283

bool interface_is_up(const char *interface){

1272

1284

struct ifreq ifr;

1273

1285

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

1284

1296

/*

1285

1297

* This function determines if a network interface is running

1286

1298

*/

1299

__attribute__((nonnull, warn_unused_result))

1287

1300

bool interface_is_running(const char *interface){

1288

1301

struct ifreq ifr;

1289

1302

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

1297

1310

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

1298

1311

}

1299

1312

1313

__attribute__((nonnull, pure, warn_unused_result))

1300

1314

int notdotentries(const struct dirent *direntry){

1301

1315

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

1302

1316

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

1309

1323

}

1310

1324

1311

1325

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

1326

__attribute__((nonnull, warn_unused_result))

1312

1327

int runnable_hook(const struct dirent *direntry){

1313

1328

int ret;

1314

1329

size_t sret;

1322

1337

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

1323

1338

"abcdefghijklmnopqrstuvwxyz"

1324

1339

"0123456789"

1325

"_-");

1340

"_.-");

1326

1341

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

1327

1342

/* Contains non-allowed characters */

1328

1343

if(debug){

1332

1347

return 0;

1333

1348

}

1334

1349

1335

char *fullname = NULL;

1336

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

1337

if(ret < 0){

1338

perror_plus("asprintf");

1339

return 0;

1340

}

1341

1342

ret = stat(fullname, &st);

1350

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

1343

1351

if(ret == -1){

1344

1352

if(debug){

1345

1353

perror_plus("Could not stat hook");

1369

1377

return 1;

1370

1378

}

1371

1379

1380

__attribute__((nonnull, warn_unused_result))

1372

1381

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1373

1382

mandos_context *mc){

1374

1383

int ret;

1378

1387

1379

1388

while(true){

1380

1389

if(mc->current_server == NULL){

1381

if (debug){

1390

if(debug){

1382

1391

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

1383

1392

" No timeout!\n");

1384

1393

}

1385

1394

ret = avahi_simple_poll_iterate(s, -1);

1386

1395

} else {

1387

if (debug){

1396

if(debug){

1388

1397

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

1389

1398

" it, or wait\n");

1390

1399

}

1407

1416

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

1408

1417

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

1409

1418

1410

if (debug){

1419

if(debug){

1411

1420

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

1412

1421

block_time);

1413

1422

}

1435

1444

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

1436

1445

}

1437

1446

if(ret != 0){

1438

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

1447

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

1439

1448

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

1440

1449

}

1441

1450

}

1443

1452

}

1444

1453

1445

1454

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

1455

__attribute__((warn_unused_result))

1446

1456

error_t raise_privileges(void){

1447

1457

error_t old_errno = errno;

1448

1458

error_t ret_errno = 0;

1449

1459

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

1450

1460

ret_errno = errno;

1451

perror_plus("seteuid");

1452

1461

}

1453

1462

errno = old_errno;

1454

1463

return ret_errno;

1455

1464

}

1456

1465

1457

1466

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

1467

__attribute__((warn_unused_result))

1458

1468

error_t raise_privileges_permanently(void){

1459

1469

error_t old_errno = errno;

1460

1470

error_t ret_errno = raise_privileges();

1464

1474

}

1465

1475

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

1466

1476

ret_errno = errno;

1467

perror_plus("seteuid");

1468

1477

}

1469

1478

errno = old_errno;

1470

1479

return ret_errno;

1471

1480

}

1472

1481

1473

1482

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

1483

__attribute__((warn_unused_result))

1474

1484

error_t lower_privileges(void){

1475

1485

error_t old_errno = errno;

1476

1486

error_t ret_errno = 0;

1477

1487

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

1478

1488

ret_errno = errno;

1479

perror_plus("seteuid");

1480

1489

}

1481

1490

errno = old_errno;

1482

1491

return ret_errno;

1483

1492

}

1484

1493

1485

1494

/* Lower privileges permanently */

1495

__attribute__((warn_unused_result))

1486

1496

error_t lower_privileges_permanently(void){

1487

1497

error_t old_errno = errno;

1488

1498

error_t ret_errno = 0;

1489

1499

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

1490

1500

ret_errno = errno;

1491

perror_plus("setuid");

1492

1501

}

1493

1502

errno = old_errno;

1494

1503

return ret_errno;

1495

1504

}

1496

1505

1497

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

1506

__attribute__((nonnull))

1507

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

1498

1508

const float delay){

1499

struct dirent **direntries;

1500

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

1501

alphasort);

1509

struct dirent **direntries = NULL;

1510

if(hookdir_fd == -1){

1511

hookdir_fd = open(hookdir, O_RDONLY);

1512

if(hookdir_fd == -1){

1513

if(errno == ENOENT){

1514

if(debug){

1515

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

1516

" found\n", hookdir);

1517

}

1518

} else {

1519

perror_plus("open");

1520

}

1521

return;

1522

}

1523

}

1524

#ifdef __GLIBC__

1525

#if __GLIBC_PREREQ(2, 15)

1526

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

1527

runnable_hook, alphasort);

1528

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

1529

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

1530

alphasort);

1531

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

1532

#else /* not __GLIBC__ */

1533

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

1534

alphasort);

1535

#endif /* not __GLIBC__ */

1502

1536

if(numhooks == -1){

1503

if(errno == ENOENT){

1504

if(debug){

1505

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

1506

" found\n", hookdir);

1507

}

1508

} else {

1509

perror_plus("scandir");

1537

perror_plus("scandir");

1538

return;

1539

}

1540

struct dirent *direntry;

1541

int ret;

1542

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

1543

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

1544

direntry = direntries[i];

1545

if(debug){

1546

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

1547

direntry->d_name);

1510

1548

}

1511

} else {

1512

struct dirent *direntry;

1513

int ret;

1514

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

1515

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

1516

direntry = direntries[i];

1517

char *fullname = NULL;

1518

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

1519

if(ret < 0){

1549

pid_t hook_pid = fork();

1550

if(hook_pid == 0){

1551

/* Child */

1552

/* Raise privileges */

1553

errno = raise_privileges_permanently();

1554

if(errno != 0){

1555

perror_plus("Failed to raise privileges");

1556

_exit(EX_NOPERM);

1557

}

1558

/* Set group */

1559

errno = 0;

1560

ret = setgid(0);

1561

if(ret == -1){

1562

perror_plus("setgid");

1563

_exit(EX_NOPERM);

1564

}

1565

/* Reset supplementary groups */

1566

errno = 0;

1567

ret = setgroups(0, NULL);

1568

if(ret == -1){

1569

perror_plus("setgroups");

1570

_exit(EX_NOPERM);

1571

}

1572

ret = dup2(devnull, STDIN_FILENO);

1573

if(ret == -1){

1574

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

1575

_exit(EX_OSERR);

1576

}

1577

ret = close(devnull);

1578

if(ret == -1){

1579

perror_plus("close");

1580

_exit(EX_OSERR);

1581

}

1582

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1583

if(ret == -1){

1584

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

1585

_exit(EX_OSERR);

1586

}

1587

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

1588

if(ret == -1){

1589

perror_plus("setenv");

1590

_exit(EX_OSERR);

1591

}

1592

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

1593

if(ret == -1){

1594

perror_plus("setenv");

1595

_exit(EX_OSERR);

1596

}

1597

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

1598

if(ret == -1){

1599

perror_plus("setenv");

1600

_exit(EX_OSERR);

1601

}

1602

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

1603

if(ret == -1){

1604

perror_plus("setenv");

1605

_exit(EX_OSERR);

1606

}

1607

char *delaystring;

1608

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

1609

if(ret == -1){

1520

1610

perror_plus("asprintf");

1521

continue;

1522

}

1523

if(debug){

1524

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

1525

direntry->d_name);

1526

}

1527

pid_t hook_pid = fork();

1528

if(hook_pid == 0){

1529

/* Child */

1530

/* Raise privileges */

1531

raise_privileges_permanently();

1532

/* Set group */

1533

errno = 0;

1534

ret = setgid(0);

1535

if(ret == -1){

1536

perror_plus("setgid");

1537

}

1538

/* Reset supplementary groups */

1539

errno = 0;

1540

ret = setgroups(0, NULL);

1541

if(ret == -1){

1542

perror_plus("setgroups");

1543

}

1544

dup2(devnull, STDIN_FILENO);

1545

close(devnull);

1546

dup2(STDERR_FILENO, STDOUT_FILENO);

1547

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

1548

if(ret == -1){

1549

perror_plus("setenv");

1550

_exit(EX_OSERR);

1551

}

1552

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

1553

if(ret == -1){

1554

perror_plus("setenv");

1555

_exit(EX_OSERR);

1556

}

1557

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

1558

if(ret == -1){

1559

perror_plus("setenv");

1560

_exit(EX_OSERR);

1561

}

1562

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

1563

if(ret == -1){

1564

perror_plus("setenv");

1565

_exit(EX_OSERR);

1566

}

1567

char *delaystring;

1568

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

1569

if(ret == -1){

1570

perror_plus("asprintf");

1571

_exit(EX_OSERR);

1572

}

1573

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

1574

if(ret == -1){

1575

free(delaystring);

1576

perror_plus("setenv");

1577

_exit(EX_OSERR);

1578

}

1611

_exit(EX_OSERR);

1612

}

1613

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

1614

if(ret == -1){

1579

1615

free(delaystring);

1580

if(connect_to != NULL){

1581

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

1582

if(ret == -1){

1583

perror_plus("setenv");

1584

_exit(EX_OSERR);

1585

}

1586

}

1587

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

1588

perror_plus("execl");

1589

_exit(EXIT_FAILURE);

1590

}

1616

perror_plus("setenv");

1617

_exit(EX_OSERR);

1618

}

1619

free(delaystring);

1620

if(connect_to != NULL){

1621

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

1622

if(ret == -1){

1623

perror_plus("setenv");

1624

_exit(EX_OSERR);

1625

}

1626

}

1627

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

1628

if(hook_fd == -1){

1629

perror_plus("openat");

1630

_exit(EXIT_FAILURE);

1631

}

1632

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

1633

perror_plus("close");

1634

_exit(EXIT_FAILURE);

1635

}

1636

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

1637

environ) == -1){

1638

perror_plus("fexecve");

1639

_exit(EXIT_FAILURE);

1640

}

1641

} else {

1642

int status;

1643

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

1644

perror_plus("waitpid");

1645

continue;

1646

}

1647

if(WIFEXITED(status)){

1648

if(WEXITSTATUS(status) != 0){

1649

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

1650

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

1651

WEXITSTATUS(status));

1652

continue;

1653

}

1654

} else if(WIFSIGNALED(status)){

1655

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

1656

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

1657

WTERMSIG(status));

1658

continue;

1591

1659

} else {

1592

int status;

1593

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

1594

perror_plus("waitpid");

1595

free(fullname);

1596

continue;

1597

}

1598

if(WIFEXITED(status)){

1599

if(WEXITSTATUS(status) != 0){

1600

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

1601

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

1602

WEXITSTATUS(status));

1603

free(fullname);

1604

continue;

1605

}

1606

} else if(WIFSIGNALED(status)){

1607

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

1608

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

1609

WTERMSIG(status));

1610

free(fullname);

1611

continue;

1612

} else {

1613

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

1614

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

1615

free(fullname);

1616

continue;

1617

}

1618

}

1619

free(fullname);

1620

if(debug){

1621

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

1622

direntry->d_name);

1623

}

1624

}

1625

close(devnull);

1626

}

1627

return true;

1660

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

1661

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

1662

continue;

1663

}

1664

}

1665

if(debug){

1666

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

1667

direntry->d_name);

1668

}

1669

}

1670

free(direntries);

1671

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

1672

perror_plus("close");

1673

} else {

1674

hookdir_fd = -1;

1675

}

1676

close(devnull);

1628

1677

}

1629

1678

1679

__attribute__((nonnull, warn_unused_result))

1630

1680

error_t bring_up_interface(const char *const interface,

1631

1681

const float delay){

1632

int sd = -1;

1633

1682

error_t old_errno = errno;

1634

error_t ret_errno = 0;

1635

int ret, ret_setflags;

1683

int ret;

1636

1684

struct ifreq network;

1637

1685

unsigned int if_index = if_nametoindex(interface);

1638

1686

if(if_index == 0){

1647

1695

}

1648

1696

1649

1697

if(not interface_is_up(interface)){

1650

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

1698

error_t ret_errno = 0, ioctl_errno = 0;

1699

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

1651

1700

ret_errno = errno;

1652

1701

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

1653

1702

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

1703

errno = old_errno;

1654

1704

return ret_errno;

1655

1705

}

1656

network.ifr_flags |= IFF_UP;

1706

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

1657

1707

1658

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1659

if(sd < 0){

1708

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

1709

if(sd == -1){

1660

1710

ret_errno = errno;

1661

1711

perror_plus("socket");

1662

1712

errno = old_errno;

1663

1713

return ret_errno;

1664

1714

}

1665

1715

1666

1716

if(quit_now){

1667

close(sd);

1717

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

1718

if(ret == -1){

1719

perror_plus("close");

1720

}

1668

1721

errno = old_errno;

1669

1722

return EINTR;

1670

1723

}

1674

1727

interface);

1675

1728

}

1676

1729

1677

/* Raise priviliges */

1678

raise_privileges();

1730

/* Raise privileges */

1731

ret_errno = raise_privileges();

1732

if(ret_errno != 0){

1733

errno = ret_errno;

1734

perror_plus("Failed to raise privileges");

1735

}

1679

1736

1680

1737

#ifdef __linux__

1681

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1682

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

1683

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

1684

bool restore_loglevel = true;

1685

if(ret_linux == -1){

1686

restore_loglevel = false;

1687

perror_plus("klogctl");

1738

int ret_linux;

1739

bool restore_loglevel = false;

1740

if(ret_errno == 0){

1741

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1742

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

1743

ret_linux = klogctl(8, NULL, 5);

1744

if(ret_linux == -1){

1745

perror_plus("klogctl");

1746

} else {

1747

restore_loglevel = true;

1748

}

1688

1749

}

1689

1750

#endif /* __linux__ */

1690

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

1691

ret_errno = errno;

1751

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

1752

ioctl_errno = errno;

1692

1753

#ifdef __linux__

1693

1754

if(restore_loglevel){

1694

1755

ret_linux = klogctl(7, NULL, 0);

1698

1759

}

1699

1760

#endif /* __linux__ */

1700

1761

1701

/* Lower privileges */

1702

lower_privileges();

1762

/* If raise_privileges() succeeded above */

1763

if(ret_errno == 0){

1764

/* Lower privileges */

1765

ret_errno = lower_privileges();

1766

if(ret_errno != 0){

1767

errno = ret_errno;

1768

perror_plus("Failed to lower privileges");

1769

}

1770

}

1703

1771

1704

1772

/* Close the socket */

1705

1773

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

1708

1776

}

1709

1777

1710

1778

if(ret_setflags == -1){

1711

errno = ret_errno;

1779

errno = ioctl_errno;

1712

1780

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1713

1781

errno = old_errno;

1714

return ret_errno;

1782

return ioctl_errno;

1715

1783

}

1716

1784

} else if(debug){

1717

1785

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

1735

1803

return 0;

1736

1804

}

1737

1805

1806

__attribute__((nonnull, warn_unused_result))

1738

1807

error_t take_down_interface(const char *const interface){

1739

1808

error_t old_errno = errno;

1740

1809

struct ifreq network;

1745

1814

return ENXIO;

1746

1815

}

1747

1816

if(interface_is_up(interface)){

1748

error_t ret_errno = 0;

1817

error_t ret_errno = 0, ioctl_errno = 0;

1749

1818

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

1750

1819

ret_errno = errno;

1751

1820

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

1752

1821

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

1822

errno = old_errno;

1753

1823

return ret_errno;

1754

1824

}

1755

1825

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

1756

1826

1757

1827

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

1758

if(sd < 0){

1828

if(sd == -1){

1759

1829

ret_errno = errno;

1760

1830

perror_plus("socket");

1761

1831

errno = old_errno;

1767

1837

interface);

1768

1838

}

1769

1839

1770

/* Raise priviliges */

1771

raise_privileges();

1840

/* Raise privileges */

1841

ret_errno = raise_privileges();

1842

if(ret_errno != 0){

1843

errno = ret_errno;

1844

perror_plus("Failed to raise privileges");

1845

}

1772

1846

1773

1847

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

1774

ret_errno = errno;

1848

ioctl_errno = errno;

1775

1849

1776

/* Lower privileges */

1777

lower_privileges();

1850

/* If raise_privileges() succeeded above */

1851

if(ret_errno == 0){

1852

/* Lower privileges */

1853

ret_errno = lower_privileges();

1854

if(ret_errno != 0){

1855

errno = ret_errno;

1856

perror_plus("Failed to lower privileges");

1857

}

1858

}

1778

1859

1779

1860

/* Close the socket */

1780

1861

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

1783

1864

}

1784

1865

1785

1866

if(ret_setflags == -1){

1786

errno = ret_errno;

1867

errno = ioctl_errno;

1787

1868

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1788

1869

errno = old_errno;

1789

return ret_errno;

1870

return ioctl_errno;

1790

1871

}

1791

1872

} else if(debug){

1792

1873

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

1800

1881

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

1801

1882

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

1802

1883

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

1803

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

1884

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

1804

1885

.interfaces = NULL, .interfaces_size = 0 };

1805

1886

AvahiSServiceBrowser *sb = NULL;

1806

1887

error_t ret_errno;

1810

1891

int exitcode = EXIT_SUCCESS;

1811

1892

char *interfaces_to_take_down = NULL;

1812

1893

size_t interfaces_to_take_down_size = 0;

1813

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

1814

bool tempdir_created = false;

1894

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

1895

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

1896

char *tempdir = NULL;

1815

1897

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1816

1898

const char *seckey = PATHDIR "/" SECKEY;

1817

1899

const char *pubkey = PATHDIR "/" PUBKEY;

1999

2081

/* Work around Debian bug #633582:

2000

2082

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

2001

2083

2002

/* Re-raise priviliges */

2003

if(raise_privileges() == 0){

2084

/* Re-raise privileges */

2085

ret_errno = raise_privileges();

2086

if(ret_errno != 0){

2087

errno = ret_errno;

2088

perror_plus("Failed to raise privileges");

2089

} else {

2004

2090

struct stat st;

2005

2091

2006

2092

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

2046

2132

}

2047

2133

2048

2134

/* Lower privileges */

2049

lower_privileges();

2135

ret_errno = lower_privileges();

2136

if(ret_errno != 0){

2137

errno = ret_errno;

2138

perror_plus("Failed to lower privileges");

2139

}

2050

2140

}

2051

2141

}

2052

2142

2078

2168

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

2079

2169

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

2080

2170

}

2081

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

2082

interfaces_hooks : "", delay)){

2083

goto end;

2084

}

2171

run_network_hooks("start", interfaces_hooks != NULL ?

2172

interfaces_hooks : "", delay);

2085

2173

}

2086

2174

2087

2175

if(not debug){

2165

2253

2166

2254

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

2167

2255

if(mc.interfaces == NULL){

2168

struct dirent **direntries;

2256

struct dirent **direntries = NULL;

2169

2257

/* Look for any good interfaces */

2170

2258

ret = scandir(sys_class_net, &direntries, good_interface,

2171

2259

alphasort);

2186

2274

}

2187

2275

free(direntries);

2188

2276

} else {

2189

free(direntries);

2277

if(ret == 0){

2278

free(direntries);

2279

}

2190

2280

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

2191

2281

exitcode = EXIT_FAILURE;

2192

2282

goto end;

2215

2305

break;

2216

2306

}

2217

2307

bool interface_was_up = interface_is_up(interface);

2218

ret = bring_up_interface(interface, delay);

2308

errno = bring_up_interface(interface, delay);

2219

2309

if(not interface_was_up){

2220

if(ret != 0){

2221

errno = ret;

2310

if(errno != 0){

2222

2311

perror_plus("Failed to bring up interface");

2223

2312

} else {

2224

ret_errno = argz_add(&interfaces_to_take_down,

2225

&interfaces_to_take_down_size,

2226

interface);

2227

if(ret_errno != 0){

2228

errno = ret_errno;

2313

errno = argz_add(&interfaces_to_take_down,

2314

&interfaces_to_take_down_size,

2315

interface);

2316

if(errno != 0){

2229

2317

perror_plus("argz_add");

2230

2318

}

2231

2319

}

2262

2350

goto end;

2263

2351

}

2264

2352

2265

if(mkdtemp(tempdir) == NULL){

2353

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

2354

tempdir = mkdtemp(run_tempdir);

2355

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

2356

if(debug){

2357

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

2358

run_tempdir, old_tempdir);

2359

}

2360

tempdir = mkdtemp(old_tempdir);

2361

}

2362

if(tempdir == NULL){

2266

2363

perror_plus("mkdtemp");

2267

2364

goto end;

2268

2365

}

2269

tempdir_created = true;

2270

2366

2271

2367

if(quit_now){

2272

2368

goto end;

2347

2443

sleep((unsigned int)retry_interval);

2348

2444

}

2349

2445

2350

if (not quit_now){

2446

if(not quit_now){

2351

2447

exitcode = EXIT_SUCCESS;

2352

2448

}

2353

2449

2408

2504

if(debug){

2409

2505

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

2410

2506

}

2411

2507

2412

2508

ret = avahi_loop_with_timeout(simple_poll,

2413

2509

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

2414

2510

if(debug){

2455

2551

}

2456

2552

}

2457

2553

2458

/* Re-raise priviliges */

2554

/* Re-raise privileges */

2459

2555

{

2460

raise_privileges();

2461

2462

/* Run network hooks */

2463

run_network_hooks("stop", interfaces_hooks != NULL ?

2464

interfaces_hooks : "", delay);

2465

2466

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

2467

{

2468

char *interface = NULL;

2469

while((interface=argz_next(interfaces_to_take_down,

2470

interfaces_to_take_down_size,

2471

interface))){

2472

ret_errno = take_down_interface(interface);

2473

if(ret_errno != 0){

2474

errno = ret_errno;

2475

perror_plus("Failed to take down interface");

2476

}

2477

}

2478

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

2479

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

2480

" down\n");

2481

}

2482

}

2483

2484

lower_privileges_permanently();

2556

ret_errno = raise_privileges();

2557

if(ret_errno != 0){

2558

errno = ret_errno;

2559

perror_plus("Failed to raise privileges");

2560

} else {

2561

2562

/* Run network hooks */

2563

run_network_hooks("stop", interfaces_hooks != NULL ?

2564

interfaces_hooks : "", delay);

2565

2566

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

2567

{

2568

char *interface = NULL;

2569

while((interface=argz_next(interfaces_to_take_down,

2570

interfaces_to_take_down_size,

2571

interface))){

2572

ret_errno = take_down_interface(interface);

2573

if(ret_errno != 0){

2574

errno = ret_errno;

2575

perror_plus("Failed to take down interface");

2576

}

2577

}

2578

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

2579

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

2580

" down\n");

2581

}

2582

}

2583

}

2584

2585

ret_errno = lower_privileges_permanently();

2586

if(ret_errno != 0){

2587

errno = ret_errno;

2588

perror_plus("Failed to lower privileges permanently");

2589

}

2485

2590

}

2486

2591

2487

2592

free(interfaces_to_take_down);

2488

2593

free(interfaces_hooks);

2489

2594

2490

2595

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

2491

if(tempdir_created){

2596

if(tempdir != NULL){

2492

2597

struct dirent **direntries = NULL;

2493

struct dirent *direntry = NULL;

2494

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

2495

alphasort);

2496

if (numentries > 0){

2497

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

2498

direntry = direntries[i];

2499

char *fullname = NULL;

2500

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

2501

direntry->d_name);

2502

if(ret < 0){

2503

perror_plus("asprintf");

2504

continue;

2505

}

2506

ret = remove(fullname);

2507

if(ret == -1){

2508

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

2509

strerror(errno));

2510

}

2511

free(fullname);

2598

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

2599

O_NOFOLLOW));

2600

if(tempdir_fd == -1){

2601

perror_plus("open");

2602

} else {

2603

#ifdef __GLIBC__

2604

#if __GLIBC_PREREQ(2, 15)

2605

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

2606

notdotentries, alphasort);

2607

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

2608

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

2609

alphasort);

2610

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

2611

#else /* not __GLIBC__ */

2612

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

2613

alphasort);

2614

#endif /* not __GLIBC__ */

2615

if(numentries >= 0){

2616

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

2617

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

2618

if(ret == -1){

2619

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

2620

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

2621

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

2622

}

2623

}

2624

2625

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

2626

free(direntries);

2627

if(numentries == -1){

2628

perror_plus("scandir");

2629

}

2630

ret = rmdir(tempdir);

2631

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

2632

perror_plus("rmdir");

2633

}

2512

2634

}

2513

}

2514

2515

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

2516

free(direntries);

2517

if (numentries == -1){

2518

perror_plus("scandir");

2519

}

2520

ret = rmdir(tempdir);

2521

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

2522

perror_plus("rmdir");

2635

TEMP_FAILURE_RETRY(close(tempdir_fd));

2523

2636

}

2524

2637

}

2525

2638