/mandos/trunk : revision 713

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);

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);

233

245

return false;

234

246

}

235

247

/* Special case of first server */

237

249

new_server->next = new_server;

238

250

new_server->prev = new_server;

239

251

*current_server = new_server;

240

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

241

252

} else {

253

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

242

254

new_server->next = *current_server;

243

255

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

244

256

new_server->prev->next = new_server;

245

257

(*current_server)->prev = new_server;

246

258

}

247

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

248

if(ret == -1){

249

perror_plus("clock_gettime");

250

return false;

251

}

252

259

return true;

253

260

}

254

261

255

262

/*

256

263

* Initialize GPGME.

257

264

*/

258

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

259

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){

260

270

gpgme_error_t rc;

261

271

gpgme_engine_info_t engine_info;

262

272

263

273

/*

264

274

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

265

275

*/

266

bool import_key(const char *filename){

276

bool import_key(const char * const filename){

267

277

int ret;

268

278

int fd;

269

279

gpgme_data_t pgp_data;

350

360

* Decrypt OpenPGP data.

351

361

* Returns -1 on error

352

362

*/

363

__attribute__((nonnull, warn_unused_result))

353

364

static ssize_t pgp_packet_decrypt(const char *cryptotext,

354

365

size_t crypto_size,

355

366

char **plaintext,

475

486

return plaintext_length;

476

487

}

477

488

478

static const char * safer_gnutls_strerror(int value){

489

__attribute__((warn_unused_result))

490

static const char *safer_gnutls_strerror(int value){

479

491

const char *ret = gnutls_strerror(value);

480

492

if(ret == NULL)

481

493

ret = "(unknown)";

483

495

}

484

496

485

497

/* GnuTLS log function callback */

498

__attribute__((nonnull))

486

499

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

487

500

const char* string){

488

501

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

489

502

}

490

503

504

__attribute__((nonnull, warn_unused_result))

491

505

static int init_gnutls_global(const char *pubkeyfilename,

492

506

const char *seckeyfilename,

493

507

mandos_context *mc){

567

581

return -1;

568

582

}

569

583

584

__attribute__((nonnull, warn_unused_result))

570

585

static int init_gnutls_session(gnutls_session_t *session,

571

586

mandos_context *mc){

572

587

int ret;

629

644

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

630

645

631

646

/* Called when a Mandos server is found */

647

__attribute__((nonnull, warn_unused_result))

632

648

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

633

649

AvahiIfIndex if_index,

634

650

int af, mandos_context *mc){

635

651

int ret, tcp_sd = -1;

636

652

ssize_t sret;

637

union {

638

struct sockaddr_in in;

639

struct sockaddr_in6 in6;

640

} to;

653

struct sockaddr_storage to;

641

654

char *buffer = NULL;

642

655

char *decrypted_buffer = NULL;

643

656

size_t buffer_length = 0;

724

737

725

738

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

726

739

if(af == AF_INET6){

727

to.in6.sin6_family = (sa_family_t)af;

728

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);

729

742

} else { /* IPv4 */

730

to.in.sin_family = (sa_family_t)af;

731

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);

732

745

}

733

746

if(ret < 0 ){

734

747

int e = errno;

743

756

goto mandos_end;

744

757

}

745

758

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

759

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

760

if(IN6_IS_ADDR_LINKLOCAL

761

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

756

762

if(if_index == AVAHI_IF_UNSPEC){

757

763

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

758

764

" incomplete without a network interface\n");

760

766

goto mandos_end;

761

767

}

762

768

/* Set the network interface number as scope */

763

to.in6.sin6_scope_id = (uint32_t)if_index;

769

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

764

770

}

765

771

} else {

766

to.in.sin_port = htons(port);

772

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

767

773

}

768

774

769

775

if(quit_now){

787

793

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

788

794

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

789

795

if(af == AF_INET6){

790

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

796

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

797

sizeof(struct sockaddr_in6),

791

798

addrstr, sizeof(addrstr), NULL, 0,

792

799

NI_NUMERICHOST);

793

800

} else {

794

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

801

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

802

sizeof(struct sockaddr_in),

795

803

addrstr, sizeof(addrstr), NULL, 0,

796

804

NI_NUMERICHOST);

797

805

}

810

818

}

811

819

812

820

if(af == AF_INET6){

813

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

821

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

822

sizeof(struct sockaddr_in6));

814

823

} else {

815

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

824

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

825

sizeof(struct sockaddr_in));

816

826

}

817

827

if(ret < 0){

818

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

828

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

819

829

int e = errno;

820

830

perror_plus("connect");

821

831

errno = e;

1036

1046

return retval;

1037

1047

}

1038

1048

1049

__attribute__((nonnull))

1039

1050

static void resolve_callback(AvahiSServiceResolver *r,

1040

1051

AvahiIfIndex interface,

1041

1052

AvahiProtocol proto,

1049

1060

AVAHI_GCC_UNUSED AvahiStringList *txt,

1050

1061

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1051

1062

flags,

1052

void* mc){

1063

void *mc){

1053

1064

if(r == NULL){

1054

1065

return;

1055

1066

}

1108

1119

const char *domain,

1109

1120

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1110

1121

flags,

1111

void* mc){

1122

void *mc){

1112

1123

if(b == NULL){

1113

1124

return;

1114

1125

}

1174

1185

errno = old_errno;

1175

1186

}

1176

1187

1188

__attribute__((nonnull, warn_unused_result))

1177

1189

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

1178

1190

int ret;

1179

1191

error_t ret_errno;

1198

1210

return true;

1199

1211

}

1200

1212

1213

__attribute__((nonnull, warn_unused_result))

1201

1214

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

1202

1215

1203

1216

/* Reject the loopback device */

1245

1258

* corresponds to an acceptable network device.

1246

1259

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

1247

1260

*/

1261

__attribute__((nonnull, warn_unused_result))

1248

1262

int good_interface(const struct dirent *if_entry){

1249

1263

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

1250

1264

return 0;

1268

1282

/*

1269

1283

* This function determines if a network interface is up.

1270

1284

*/

1285

__attribute__((nonnull, warn_unused_result))

1271

1286

bool interface_is_up(const char *interface){

1272

1287

struct ifreq ifr;

1273

1288

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

1284

1299

/*

1285

1300

* This function determines if a network interface is running

1286

1301

*/

1302

__attribute__((nonnull, warn_unused_result))

1287

1303

bool interface_is_running(const char *interface){

1288

1304

struct ifreq ifr;

1289

1305

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

1297

1313

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

1298

1314

}

1299

1315

1316

__attribute__((nonnull, pure, warn_unused_result))

1300

1317

int notdotentries(const struct dirent *direntry){

1301

1318

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

1302

1319

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

1309

1326

}

1310

1327

1311

1328

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

1329

__attribute__((nonnull, warn_unused_result))

1312

1330

int runnable_hook(const struct dirent *direntry){

1313

1331

int ret;

1314

1332

size_t sret;

1322

1340

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

1323

1341

"abcdefghijklmnopqrstuvwxyz"

1324

1342

"0123456789"

1325

"_-");

1343

"_.-");

1326

1344

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

1327

1345

/* Contains non-allowed characters */

1328

1346

if(debug){

1332

1350

return 0;

1333

1351

}

1334

1352

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);

1353

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

1343

1354

if(ret == -1){

1344

1355

if(debug){

1345

1356

perror_plus("Could not stat hook");

1369

1380

return 1;

1370

1381

}

1371

1382

1383

__attribute__((nonnull, warn_unused_result))

1372

1384

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1373

1385

mandos_context *mc){

1374

1386

int ret;

1378

1390

1379

1391

while(true){

1380

1392

if(mc->current_server == NULL){

1381

if (debug){

1393

if(debug){

1382

1394

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

1383

1395

" No timeout!\n");

1384

1396

}

1385

1397

ret = avahi_simple_poll_iterate(s, -1);

1386

1398

} else {

1387

if (debug){

1399

if(debug){

1388

1400

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

1389

1401

" it, or wait\n");

1390

1402

}

1407

1419

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

1408

1420

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

1409

1421

1410

if (debug){

1422

if(debug){

1411

1423

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

1412

1424

block_time);

1413

1425

}

1435

1447

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

1436

1448

}

1437

1449

if(ret != 0){

1438

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

1450

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

1439

1451

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

1440

1452

}

1441

1453

}

1443

1455

}

1444

1456

1445

1457

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

1458

__attribute__((warn_unused_result))

1446

1459

error_t raise_privileges(void){

1447

1460

error_t old_errno = errno;

1448

1461

error_t ret_errno = 0;

1449

1462

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

1450

1463

ret_errno = errno;

1451

perror_plus("seteuid");

1452

1464

}

1453

1465

errno = old_errno;

1454

1466

return ret_errno;

1455

1467

}

1456

1468

1457

1469

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

1470

__attribute__((warn_unused_result))

1458

1471

error_t raise_privileges_permanently(void){

1459

1472

error_t old_errno = errno;

1460

1473

error_t ret_errno = raise_privileges();

1464

1477

}

1465

1478

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

1466

1479

ret_errno = errno;

1467

perror_plus("seteuid");

1468

1480

}

1469

1481

errno = old_errno;

1470

1482

return ret_errno;

1471

1483

}

1472

1484

1473

1485

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

1486

__attribute__((warn_unused_result))

1474

1487

error_t lower_privileges(void){

1475

1488

error_t old_errno = errno;

1476

1489

error_t ret_errno = 0;

1477

1490

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

1478

1491

ret_errno = errno;

1479

perror_plus("seteuid");

1480

1492

}

1481

1493

errno = old_errno;

1482

1494

return ret_errno;

1483

1495

}

1484

1496

1485

1497

/* Lower privileges permanently */

1498

__attribute__((warn_unused_result))

1486

1499

error_t lower_privileges_permanently(void){

1487

1500

error_t old_errno = errno;

1488

1501

error_t ret_errno = 0;

1489

1502

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

1490

1503

ret_errno = errno;

1491

perror_plus("setuid");

1492

1504

}

1493

1505

errno = old_errno;

1494

1506

return ret_errno;

1495

1507

}

1496

1508

1497

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

1509

__attribute__((nonnull))

1510

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

1498

1511

const float delay){

1499

struct dirent **direntries;

1500

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

1501

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__ */

1502

1539

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");

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);

1510

1551

}

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){

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){

1520

1613

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

}

1614

_exit(EX_OSERR);

1615

}

1616

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

1617

if(ret == -1){

1579

1618

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

}

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;

1591

1662

} 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;

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);

1628

1680

}

1629

1681

1682

__attribute__((nonnull, warn_unused_result))

1630

1683

error_t bring_up_interface(const char *const interface,

1631

1684

const float delay){

1632

int sd = -1;

1633

1685

error_t old_errno = errno;

1634

error_t ret_errno = 0;

1635

int ret, ret_setflags;

1686

int ret;

1636

1687

struct ifreq network;

1637

1688

unsigned int if_index = if_nametoindex(interface);

1638

1689

if(if_index == 0){

1647

1698

}

1648

1699

1649

1700

if(not interface_is_up(interface)){

1650

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

1701

error_t ret_errno = 0, ioctl_errno = 0;

1702

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

1651

1703

ret_errno = errno;

1652

1704

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

1653

1705

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

1706

errno = old_errno;

1654

1707

return ret_errno;

1655

1708

}

1656

network.ifr_flags |= IFF_UP;

1709

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

1657

1710

1658

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1659

if(sd < 0){

1711

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

1712

if(sd == -1){

1660

1713

ret_errno = errno;

1661

1714

perror_plus("socket");

1662

1715

errno = old_errno;

1663

1716

return ret_errno;

1664

1717

}

1665

1718

1666

1719

if(quit_now){

1667

close(sd);

1720

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

1721

if(ret == -1){

1722

perror_plus("close");

1723

}

1668

1724

errno = old_errno;

1669

1725

return EINTR;

1670

1726

}

1674

1730

interface);

1675

1731

}

1676

1732

1677

/* Raise priviliges */

1678

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

}

1679

1739

1680

1740

#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");

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

}

1688

1752

}

1689

1753

#endif /* __linux__ */

1690

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

1691

ret_errno = errno;

1754

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

1755

ioctl_errno = errno;

1692

1756

#ifdef __linux__

1693

1757

if(restore_loglevel){

1694

1758

ret_linux = klogctl(7, NULL, 0);

1698

1762

}

1699

1763

#endif /* __linux__ */

1700

1764

1701

/* Lower privileges */

1702

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

}

1703

1774

1704

1775

/* Close the socket */

1705

1776

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

1708

1779

}

1709

1780

1710

1781

if(ret_setflags == -1){

1711

errno = ret_errno;

1782

errno = ioctl_errno;

1712

1783

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1713

1784

errno = old_errno;

1714

return ret_errno;

1785

return ioctl_errno;

1715

1786

}

1716

1787

} else if(debug){

1717

1788

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

1735

1806

return 0;

1736

1807

}

1737

1808

1809

__attribute__((nonnull, warn_unused_result))

1738

1810

error_t take_down_interface(const char *const interface){

1739

1811

error_t old_errno = errno;

1740

1812

struct ifreq network;

1745

1817

return ENXIO;

1746

1818

}

1747

1819

if(interface_is_up(interface)){

1748

error_t ret_errno = 0;

1820

error_t ret_errno = 0, ioctl_errno = 0;

1749

1821

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

1750

1822

ret_errno = errno;

1751

1823

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

1752

1824

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

1825

errno = old_errno;

1753

1826

return ret_errno;

1754

1827

}

1755

1828

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

1756

1829

1757

1830

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

1758

if(sd < 0){

1831

if(sd == -1){

1759

1832

ret_errno = errno;

1760

1833

perror_plus("socket");

1761

1834

errno = old_errno;

1767

1840

interface);

1768

1841

}

1769

1842

1770

/* Raise priviliges */

1771

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

}

1772

1849

1773

1850

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

1774

ret_errno = errno;

1851

ioctl_errno = errno;

1775

1852

1776

/* Lower privileges */

1777

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

}

1778

1862

1779

1863

/* Close the socket */

1780

1864

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

1783

1867

}

1784

1868

1785

1869

if(ret_setflags == -1){

1786

errno = ret_errno;

1870

errno = ioctl_errno;

1787

1871

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1788

1872

errno = old_errno;

1789

return ret_errno;

1873

return ioctl_errno;

1790

1874

}

1791

1875

} else if(debug){

1792

1876

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

1800

1884

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

1801

1885

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

1802

1886

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

1803

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

1887

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

1804

1888

.interfaces = NULL, .interfaces_size = 0 };

1805

1889

AvahiSServiceBrowser *sb = NULL;

1806

1890

error_t ret_errno;

1810

1894

int exitcode = EXIT_SUCCESS;

1811

1895

char *interfaces_to_take_down = NULL;

1812

1896

size_t interfaces_to_take_down_size = 0;

1813

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

1814

bool tempdir_created = false;

1897

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

1898

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

1899

char *tempdir = NULL;

1815

1900

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1816

1901

const char *seckey = PATHDIR "/" SECKEY;

1817

1902

const char *pubkey = PATHDIR "/" PUBKEY;

1999

2084

/* Work around Debian bug #633582:

2000

2085

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

2001

2086

2002

/* Re-raise priviliges */

2003

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 {

2004

2093

struct stat st;

2005

2094

2006

2095

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

2046

2135

}

2047

2136

2048

2137

/* Lower privileges */

2049

lower_privileges();

2138

ret_errno = lower_privileges();

2139

if(ret_errno != 0){

2140

errno = ret_errno;

2141

perror_plus("Failed to lower privileges");

2142

}

2050

2143

}

2051

2144

}

2052

2145

2078

2171

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

2079

2172

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

2080

2173

}

2081

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

2082

interfaces_hooks : "", delay)){

2083

goto end;

2084

}

2174

run_network_hooks("start", interfaces_hooks != NULL ?

2175

interfaces_hooks : "", delay);

2085

2176

}

2086

2177

2087

2178

if(not debug){

2165

2256

2166

2257

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

2167

2258

if(mc.interfaces == NULL){

2168

struct dirent **direntries;

2259

struct dirent **direntries = NULL;

2169

2260

/* Look for any good interfaces */

2170

2261

ret = scandir(sys_class_net, &direntries, good_interface,

2171

2262

alphasort);

2186

2277

}

2187

2278

free(direntries);

2188

2279

} else {

2189

free(direntries);

2280

if(ret == 0){

2281

free(direntries);

2282

}

2190

2283

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

2191

2284

exitcode = EXIT_FAILURE;

2192

2285

goto end;

2215

2308

break;

2216

2309

}

2217

2310

bool interface_was_up = interface_is_up(interface);

2218

ret = bring_up_interface(interface, delay);

2311

errno = bring_up_interface(interface, delay);

2219

2312

if(not interface_was_up){

2220

if(ret != 0){

2221

errno = ret;

2313

if(errno != 0){

2222

2314

perror_plus("Failed to bring up interface");

2223

2315

} 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;

2316

errno = argz_add(&interfaces_to_take_down,

2317

&interfaces_to_take_down_size,

2318

interface);

2319

if(errno != 0){

2229

2320

perror_plus("argz_add");

2230

2321

}

2231

2322

}

2262

2353

goto end;

2263

2354

}

2264

2355

2265

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){

2266

2366

perror_plus("mkdtemp");

2267

2367

goto end;

2268

2368

}

2269

tempdir_created = true;

2270

2369

2271

2370

if(quit_now){

2272

2371

goto end;

2347

2446

sleep((unsigned int)retry_interval);

2348

2447

}

2349

2448

2350

if (not quit_now){

2449

if(not quit_now){

2351

2450

exitcode = EXIT_SUCCESS;

2352

2451

}

2353

2452

2408

2507

if(debug){

2409

2508

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

2410

2509

}

2411

2510

2412

2511

ret = avahi_loop_with_timeout(simple_poll,

2413

2512

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

2414

2513

if(debug){

2455

2554

}

2456

2555

}

2457

2556

2458

/* Re-raise priviliges */

2557

/* Re-raise privileges */

2459

2558

{

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();

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

}

2485

2593

}

2486

2594

2487

2595

free(interfaces_to_take_down);

2488

2596

free(interfaces_hooks);

2489

2597

2490

2598

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

2491

if(tempdir_created){

2599

if(tempdir != NULL){

2492

2600

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);

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

}

2512

2637

}

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");

2638

TEMP_FAILURE_RETRY(close(tempdir_fd));

2523

2639

}

2524

2640

}

2525

2641