/mandos/trunk : revision 654

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 /* not _LARGEFILE_SOURCE */

35

#endif

36

#ifndef _FILE_OFFSET_BITS

37

#define _FILE_OFFSET_BITS 64

38

#endif /* not _FILE_OFFSET_BITS */

38

#endif

39

40

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

41

42

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

43

stdout, ferror() */

43

stdout, ferror(), remove() */

44

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

45

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

46

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

55

opendir(), DIR */

56

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

57

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

58

inet_pton(), connect(),

59

getnameinfo() */

60

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

58

inet_pton(), connect() */

59

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

61

60

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

62

61

*/

63

62

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

73

72

*/

74

73

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

75

74

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

76

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

77

unlinkat() */

78

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

75

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

76

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

79

77

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

80

78

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

81

79

argp_state, struct argp,

93

91

argz_delete(), argz_append(),

94

92

argz_stringify(), argz_add(),

95

93

argz_count() */

96

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

97

EAI_SYSTEM, gai_strerror() */

98

94

99

95

#ifdef __linux__

100

96

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

142

138

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

143

139

char *connect_to = NULL;

144

140

const char *hookdir = HOOKDIR;

145

int hookdir_fd = -1;

146

141

uid_t uid = 65534;

147

142

gid_t gid = 65534;

148

143

185

180

perror(print_text);

186

181

}

187

182

188

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

183

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

189

184

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

190

185

va_list ap;

191

186

va_start (ap, format);

200

195

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

201

196

* "buffer_length" is how much is already used.

202

197

*/

203

__attribute__((nonnull, warn_unused_result))

204

198

size_t incbuffer(char **buffer, size_t buffer_length,

205

199

size_t buffer_capacity){

206

200

if(buffer_length + BUFFER_SIZE > buffer_capacity){

207

char *new_buf = realloc(*buffer, buffer_capacity + BUFFER_SIZE);

208

if(new_buf == NULL){

209

int old_errno = errno;

210

free(*buffer);

211

errno = old_errno;

212

*buffer = NULL;

201

*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);

202

if(buffer == NULL){

213

203

return 0;

214

204

}

215

*buffer = new_buf;

216

205

buffer_capacity += BUFFER_SIZE;

217

206

}

218

207

return buffer_capacity;

219

208

}

220

209

221

210

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

222

__attribute__((nonnull, warn_unused_result))

223

211

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

224

212

int af, server **current_server){

225

213

int ret;

234

222

.af = af };

235

223

if(new_server->ip == NULL){

236

224

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);

245

225

return false;

246

226

}

247

227

/* Special case of first server */

249

229

new_server->next = new_server;

250

230

new_server->prev = new_server;

251

231

*current_server = new_server;

232

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

252

233

} else {

253

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

254

234

new_server->next = *current_server;

255

235

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

256

236

new_server->prev->next = new_server;

257

237

(*current_server)->prev = new_server;

258

238

}

239

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

240

if(ret == -1){

241

perror_plus("clock_gettime");

242

return false;

243

}

259

244

return true;

260

245

}

261

246

262

247

/*

263

248

* Initialize GPGME.

264

249

*/

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){

250

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

251

const char *tempdir, mandos_context *mc){

270

252

gpgme_error_t rc;

271

253

gpgme_engine_info_t engine_info;

272

254

273

255

/*

274

256

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

275

257

*/

276

bool import_key(const char * const filename){

258

bool import_key(const char *filename){

277

259

int ret;

278

260

int fd;

279

261

gpgme_data_t pgp_data;

360

342

* Decrypt OpenPGP data.

361

343

* Returns -1 on error

362

344

*/

363

__attribute__((nonnull, warn_unused_result))

364

345

static ssize_t pgp_packet_decrypt(const char *cryptotext,

365

346

size_t crypto_size,

366

347

char **plaintext,

486

467

return plaintext_length;

487

468

}

488

469

489

__attribute__((warn_unused_result))

490

static const char *safer_gnutls_strerror(int value){

470

static const char * safer_gnutls_strerror(int value){

491

471

const char *ret = gnutls_strerror(value);

492

472

if(ret == NULL)

493

473

ret = "(unknown)";

495

475

}

496

476

497

477

/* GnuTLS log function callback */

498

__attribute__((nonnull))

499

478

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

500

479

const char* string){

501

480

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

502

481

}

503

482

504

__attribute__((nonnull, warn_unused_result))

505

483

static int init_gnutls_global(const char *pubkeyfilename,

506

484

const char *seckeyfilename,

507

485

mandos_context *mc){

581

559

return -1;

582

560

}

583

561

584

__attribute__((nonnull, warn_unused_result))

585

562

static int init_gnutls_session(gnutls_session_t *session,

586

563

mandos_context *mc){

587

564

int ret;

644

621

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

645

622

646

623

/* Called when a Mandos server is found */

647

__attribute__((nonnull, warn_unused_result))

648

624

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

649

625

AvahiIfIndex if_index,

650

626

int af, mandos_context *mc){

651

627

int ret, tcp_sd = -1;

652

628

ssize_t sret;

653

struct sockaddr_storage to;

629

union {

630

struct sockaddr_in in;

631

struct sockaddr_in6 in6;

632

} to;

654

633

char *buffer = NULL;

655

634

char *decrypted_buffer = NULL;

656

635

size_t buffer_length = 0;

737

716

738

717

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

739

718

if(af == AF_INET6){

740

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

741

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

719

to.in6.sin6_family = (sa_family_t)af;

720

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

742

721

} else { /* IPv4 */

743

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

744

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

722

to.in.sin_family = (sa_family_t)af;

723

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

745

724

}

746

725

if(ret < 0 ){

747

726

int e = errno;

756

735

goto mandos_end;

757

736

}

758

737

if(af == AF_INET6){

759

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

760

if(IN6_IS_ADDR_LINKLOCAL

761

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

738

to.in6.sin6_port = htons(port);

739

#ifdef __GNUC__

740

#pragma GCC diagnostic push

741

#pragma GCC diagnostic ignored "-Wstrict-aliasing"

742

#endif

743

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

744

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

745

#ifdef __GNUC__

746

#pragma GCC diagnostic pop

747

#endif

762

748

if(if_index == AVAHI_IF_UNSPEC){

763

749

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

764

750

" incomplete without a network interface\n");

766

752

goto mandos_end;

767

753

}

768

754

/* Set the network interface number as scope */

769

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

755

to.in6.sin6_scope_id = (uint32_t)if_index;

770

756

}

771

757

} else {

772

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

758

to.in.sin_port = htons(port);

773

759

}

774

760

775

761

if(quit_now){

792

778

}

793

779

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

794

780

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

781

const char *pcret;

795

782

if(af == AF_INET6){

796

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

797

sizeof(struct sockaddr_in6),

798

addrstr, sizeof(addrstr), NULL, 0,

799

NI_NUMERICHOST);

783

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

784

sizeof(addrstr));

800

785

} else {

801

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

802

sizeof(struct sockaddr_in),

803

addrstr, sizeof(addrstr), NULL, 0,

804

NI_NUMERICHOST);

786

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

787

sizeof(addrstr));

805

788

}

806

if(ret == EAI_SYSTEM){

807

perror_plus("getnameinfo");

808

} else if(ret != 0) {

809

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

810

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

811

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

789

if(pcret == NULL){

790

perror_plus("inet_ntop");

791

} else {

792

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

793

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

794

}

812

795

}

813

796

}

814

797

818

801

}

819

802

820

803

if(af == AF_INET6){

821

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

822

sizeof(struct sockaddr_in6));

804

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

823

805

} else {

824

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

825

sizeof(struct sockaddr_in));

806

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

826

807

}

827

808

if(ret < 0){

828

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

809

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

829

810

int e = errno;

830

811

perror_plus("connect");

831

812

errno = e;

1046

1027

return retval;

1047

1028

}

1048

1029

1049

__attribute__((nonnull))

1050

1030

static void resolve_callback(AvahiSServiceResolver *r,

1051

1031

AvahiIfIndex interface,

1052

1032

AvahiProtocol proto,

1060

1040

AVAHI_GCC_UNUSED AvahiStringList *txt,

1061

1041

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1062

1042

flags,

1063

void *mc){

1043

void* mc){

1064

1044

if(r == NULL){

1065

1045

return;

1066

1046

}

1119

1099

const char *domain,

1120

1100

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1121

1101

flags,

1122

void *mc){

1102

void* mc){

1123

1103

if(b == NULL){

1124

1104

return;

1125

1105

}

1185

1165

errno = old_errno;

1186

1166

}

1187

1167

1188

__attribute__((nonnull, warn_unused_result))

1189

1168

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

1190

1169

int ret;

1191

1170

error_t ret_errno;

1210

1189

return true;

1211

1190

}

1212

1191

1213

__attribute__((nonnull, warn_unused_result))

1214

1192

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

1215

1193

1216

1194

/* Reject the loopback device */

1258

1236

* corresponds to an acceptable network device.

1259

1237

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

1260

1238

*/

1261

__attribute__((nonnull, warn_unused_result))

1262

1239

int good_interface(const struct dirent *if_entry){

1263

1240

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

1264

1241

return 0;

1282

1259

/*

1283

1260

* This function determines if a network interface is up.

1284

1261

*/

1285

__attribute__((nonnull, warn_unused_result))

1286

1262

bool interface_is_up(const char *interface){

1287

1263

struct ifreq ifr;

1288

1264

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

1299

1275

/*

1300

1276

* This function determines if a network interface is running

1301

1277

*/

1302

__attribute__((nonnull, warn_unused_result))

1303

1278

bool interface_is_running(const char *interface){

1304

1279

struct ifreq ifr;

1305

1280

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

1313

1288

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

1314

1289

}

1315

1290

1316

__attribute__((nonnull, pure, warn_unused_result))

1317

1291

int notdotentries(const struct dirent *direntry){

1318

1292

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

1319

1293

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

1326

1300

}

1327

1301

1328

1302

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

1329

__attribute__((nonnull, warn_unused_result))

1330

1303

int runnable_hook(const struct dirent *direntry){

1331

1304

int ret;

1332

1305

size_t sret;

1340

1313

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

1341

1314

"abcdefghijklmnopqrstuvwxyz"

1342

1315

"0123456789"

1343

"_.-");

1316

"_-");

1344

1317

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

1345

1318

/* Contains non-allowed characters */

1346

1319

if(debug){

1350

1323

return 0;

1351

1324

}

1352

1325

1353

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

1326

char *fullname = NULL;

1327

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

1328

if(ret < 0){

1329

perror_plus("asprintf");

1330

return 0;

1331

}

1332

1333

ret = stat(fullname, &st);

1354

1334

if(ret == -1){

1355

1335

if(debug){

1356

1336

perror_plus("Could not stat hook");

1380

1360

return 1;

1381

1361

}

1382

1362

1383

__attribute__((nonnull, warn_unused_result))

1384

1363

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1385

1364

mandos_context *mc){

1386

1365

int ret;

1390

1369

1391

1370

while(true){

1392

1371

if(mc->current_server == NULL){

1393

if(debug){

1372

if (debug){

1394

1373

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

1395

1374

" No timeout!\n");

1396

1375

}

1397

1376

ret = avahi_simple_poll_iterate(s, -1);

1398

1377

} else {

1399

if(debug){

1378

if (debug){

1400

1379

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

1401

1380

" it, or wait\n");

1402

1381

}

1419

1398

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

1420

1399

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

1421

1400

1422

if(debug){

1401

if (debug){

1423

1402

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

1424

1403

block_time);

1425

1404

}

1447

1426

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

1448

1427

}

1449

1428

if(ret != 0){

1450

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

1429

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

1451

1430

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

1452

1431

}

1453

1432

}

1455

1434

}

1456

1435

1457

1436

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

1458

__attribute__((warn_unused_result))

1459

1437

error_t raise_privileges(void){

1460

1438

error_t old_errno = errno;

1461

1439

error_t ret_errno = 0;

1462

1440

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

1463

1441

ret_errno = errno;

1442

perror_plus("seteuid");

1464

1443

}

1465

1444

errno = old_errno;

1466

1445

return ret_errno;

1467

1446

}

1468

1447

1469

1448

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

1470

__attribute__((warn_unused_result))

1471

1449

error_t raise_privileges_permanently(void){

1472

1450

error_t old_errno = errno;

1473

1451

error_t ret_errno = raise_privileges();

1477

1455

}

1478

1456

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

1479

1457

ret_errno = errno;

1458

perror_plus("seteuid");

1480

1459

}

1481

1460

errno = old_errno;

1482

1461

return ret_errno;

1483

1462

}

1484

1463

1485

1464

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

1486

__attribute__((warn_unused_result))

1487

1465

error_t lower_privileges(void){

1488

1466

error_t old_errno = errno;

1489

1467

error_t ret_errno = 0;

1490

1468

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

1491

1469

ret_errno = errno;

1470

perror_plus("seteuid");

1492

1471

}

1493

1472

errno = old_errno;

1494

1473

return ret_errno;

1495

1474

}

1496

1475

1497

1476

/* Lower privileges permanently */

1498

__attribute__((warn_unused_result))

1499

1477

error_t lower_privileges_permanently(void){

1500

1478

error_t old_errno = errno;

1501

1479

error_t ret_errno = 0;

1502

1480

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

1503

1481

ret_errno = errno;

1482

perror_plus("setuid");

1504

1483

}

1505

1484

errno = old_errno;

1506

1485

return ret_errno;

1507

1486

}

1508

1487

1509

__attribute__((nonnull))

1510

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

1488

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

1511

1489

const float delay){

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__ */

1490

struct dirent **direntries;

1491

struct dirent *direntry;

1492

int ret;

1493

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

1494

alphasort);

1539

1495

if(numhooks == -1){

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);

1496

if(errno == ENOENT){

1497

if(debug){

1498

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

1499

" found\n", hookdir);

1500

}

1501

} else {

1502

perror_plus("scandir");

1551

1503

}

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){

1504

} else {

1505

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

1506

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

1507

direntry = direntries[i];

1508

char *fullname = NULL;

1509

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

1510

if(ret < 0){

1613

1511

perror_plus("asprintf");

1614

_exit(EX_OSERR);

1615

}

1616

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

1617

if(ret == -1){

1512

continue;

1513

}

1514

if(debug){

1515

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

1516

direntry->d_name);

1517

}

1518

pid_t hook_pid = fork();

1519

if(hook_pid == 0){

1520

/* Child */

1521

/* Raise privileges */

1522

raise_privileges_permanently();

1523

/* Set group */

1524

errno = 0;

1525

ret = setgid(0);

1526

if(ret == -1){

1527

perror_plus("setgid");

1528

}

1529

/* Reset supplementary groups */

1530

errno = 0;

1531

ret = setgroups(0, NULL);

1532

if(ret == -1){

1533

perror_plus("setgroups");

1534

}

1535

dup2(devnull, STDIN_FILENO);

1536

close(devnull);

1537

dup2(STDERR_FILENO, STDOUT_FILENO);

1538

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

1539

if(ret == -1){

1540

perror_plus("setenv");

1541

_exit(EX_OSERR);

1542

}

1543

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

1544

if(ret == -1){

1545

perror_plus("setenv");

1546

_exit(EX_OSERR);

1547

}

1548

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

1549

if(ret == -1){

1550

perror_plus("setenv");

1551

_exit(EX_OSERR);

1552

}

1553

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

1554

if(ret == -1){

1555

perror_plus("setenv");

1556

_exit(EX_OSERR);

1557

}

1558

char *delaystring;

1559

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

1560

if(ret == -1){

1561

perror_plus("asprintf");

1562

_exit(EX_OSERR);

1563

}

1564

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

1565

if(ret == -1){

1566

free(delaystring);

1567

perror_plus("setenv");

1568

_exit(EX_OSERR);

1569

}

1618

1570

free(delaystring);

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;

1571

if(connect_to != NULL){

1572

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

1573

if(ret == -1){

1574

perror_plus("setenv");

1575

_exit(EX_OSERR);

1576

}

1577

}

1578

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

1579

perror_plus("execl");

1580

_exit(EXIT_FAILURE);

1581

}

1662

1582

} else {

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);

1583

int status;

1584

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

1585

perror_plus("waitpid");

1586

free(fullname);

1587

continue;

1588

}

1589

if(WIFEXITED(status)){

1590

if(WEXITSTATUS(status) != 0){

1591

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

1592

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

1593

WEXITSTATUS(status));

1594

free(fullname);

1595

continue;

1596

}

1597

} else if(WIFSIGNALED(status)){

1598

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

1599

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

1600

WTERMSIG(status));

1601

free(fullname);

1602

continue;

1603

} else {

1604

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

1605

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

1606

free(fullname);

1607

continue;

1608

}

1609

}

1610

free(fullname);

1611

if(debug){

1612

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

1613

direntry->d_name);

1614

}

1615

}

1616

close(devnull);

1617

}

1618

return true;

1680

1619

}

1681

1620

1682

__attribute__((nonnull, warn_unused_result))

1683

1621

error_t bring_up_interface(const char *const interface,

1684

1622

const float delay){

1623

int sd = -1;

1685

1624

error_t old_errno = errno;

1686

int ret;

1625

error_t ret_errno = 0;

1626

int ret, ret_setflags;

1687

1627

struct ifreq network;

1688

1628

unsigned int if_index = if_nametoindex(interface);

1689

1629

if(if_index == 0){

1698

1638

}

1699

1639

1700

1640

if(not interface_is_up(interface)){

1701

error_t ret_errno = 0, ioctl_errno = 0;

1702

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

1641

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

1703

1642

ret_errno = errno;

1704

1643

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

1705

1644

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

1706

errno = old_errno;

1707

1645

return ret_errno;

1708

1646

}

1709

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

1647

network.ifr_flags |= IFF_UP;

1710

1648

1711

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

1712

if(sd == -1){

1649

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1650

if(sd < 0){

1713

1651

ret_errno = errno;

1714

1652

perror_plus("socket");

1715

1653

errno = old_errno;

1716

1654

return ret_errno;

1717

1655

}

1718

1656

1719

1657

if(quit_now){

1720

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

1721

if(ret == -1){

1722

perror_plus("close");

1723

}

1658

close(sd);

1724

1659

errno = old_errno;

1725

1660

return EINTR;

1726

1661

}

1730

1665

interface);

1731

1666

}

1732

1667

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

}

1668

/* Raise priviliges */

1669

raise_privileges();

1739

1670

1740

1671

#ifdef __linux__

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

}

1672

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1673

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

1674

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

1675

bool restore_loglevel = true;

1676

if(ret_linux == -1){

1677

restore_loglevel = false;

1678

perror_plus("klogctl");

1752

1679

}

1753

1680

#endif /* __linux__ */

1754

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

1755

ioctl_errno = errno;

1681

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

1682

ret_errno = errno;

1756

1683

#ifdef __linux__

1757

1684

if(restore_loglevel){

1758

1685

ret_linux = klogctl(7, NULL, 0);

1762

1689

}

1763

1690

#endif /* __linux__ */

1764

1691

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

}

1692

/* Lower privileges */

1693

lower_privileges();

1774

1694

1775

1695

/* Close the socket */

1776

1696

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

1779

1699

}

1780

1700

1781

1701

if(ret_setflags == -1){

1782

errno = ioctl_errno;

1702

errno = ret_errno;

1783

1703

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1784

1704

errno = old_errno;

1785

return ioctl_errno;

1705

return ret_errno;

1786

1706

}

1787

1707

} else if(debug){

1788

1708

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

1806

1726

return 0;

1807

1727

}

1808

1728

1809

__attribute__((nonnull, warn_unused_result))

1810

1729

error_t take_down_interface(const char *const interface){

1730

int sd = -1;

1811

1731

error_t old_errno = errno;

1732

error_t ret_errno = 0;

1733

int ret, ret_setflags;

1812

1734

struct ifreq network;

1813

1735

unsigned int if_index = if_nametoindex(interface);

1814

1736

if(if_index == 0){

1817

1739

return ENXIO;

1818

1740

}

1819

1741

if(interface_is_up(interface)){

1820

error_t ret_errno = 0, ioctl_errno = 0;

1821

1742

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

1822

1743

ret_errno = errno;

1823

1744

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

1824

1745

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

1825

errno = old_errno;

1826

1746

return ret_errno;

1827

1747

}

1828

1748

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

1829

1749

1830

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

1831

if(sd == -1){

1750

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1751

if(sd < 0){

1832

1752

ret_errno = errno;

1833

1753

perror_plus("socket");

1834

1754

errno = old_errno;

1840

1760

interface);

1841

1761

}

1842

1762

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

}

1849

1850

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

1851

ioctl_errno = errno;

1852

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

}

1763

/* Raise priviliges */

1764

raise_privileges();

1765

1766

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

1767

ret_errno = errno;

1768

1769

/* Lower privileges */

1770

lower_privileges();

1862

1771

1863

1772

/* Close the socket */

1864

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

1773

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

1865

1774

if(ret == -1){

1866

1775

perror_plus("close");

1867

1776

}

1868

1777

1869

1778

if(ret_setflags == -1){

1870

errno = ioctl_errno;

1779

errno = ret_errno;

1871

1780

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1872

1781

errno = old_errno;

1873

return ioctl_errno;

1782

return ret_errno;

1874

1783

}

1875

1784

} else if(debug){

1876

1785

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

1884

1793

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

1885

1794

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

1886

1795

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

1887

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

1796

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

1888

1797

.interfaces = NULL, .interfaces_size = 0 };

1889

1798

AvahiSServiceBrowser *sb = NULL;

1890

1799

error_t ret_errno;

1894

1803

int exitcode = EXIT_SUCCESS;

1895

1804

char *interfaces_to_take_down = NULL;

1896

1805

size_t interfaces_to_take_down_size = 0;

1897

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

1898

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

1899

char *tempdir = NULL;

1806

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

1807

bool tempdir_created = false;

1900

1808

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1901

1809

const char *seckey = PATHDIR "/" SECKEY;

1902

1810

const char *pubkey = PATHDIR "/" PUBKEY;

1903

1811

char *interfaces_hooks = NULL;

1812

size_t interfaces_hooks_size = 0;

1904

1813

1905

1814

bool gnutls_initialized = false;

1906

1815

bool gpgme_initialized = false;

2084

1993

/* Work around Debian bug #633582:

2085

1994

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

2086

1995

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 {

1996

/* Re-raise priviliges */

1997

if(raise_privileges() == 0){

2093

1998

struct stat st;

2094

1999

2095

2000

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

2135

2040

}

2136

2041

2137

2042

/* Lower privileges */

2138

ret_errno = lower_privileges();

2139

if(ret_errno != 0){

2140

errno = ret_errno;

2141

perror_plus("Failed to lower privileges");

2142

}

2043

lower_privileges();

2143

2044

}

2144

2045

}

2145

2046

2169

2070

goto end;

2170

2071

}

2171

2072

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

2172

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

2173

}

2174

run_network_hooks("start", interfaces_hooks != NULL ?

2175

interfaces_hooks : "", delay);

2073

interfaces_hooks_size = mc.interfaces_size;

2074

argz_stringify(interfaces_hooks, interfaces_hooks_size,

2075

(int)',');

2076

}

2077

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

2078

interfaces_hooks : "", delay)){

2079

goto end;

2080

}

2176

2081

}

2177

2082

2178

2083

if(not debug){

2256

2161

2257

2162

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

2258

2163

if(mc.interfaces == NULL){

2259

struct dirent **direntries = NULL;

2164

struct dirent **direntries;

2260

2165

/* Look for any good interfaces */

2261

2166

ret = scandir(sys_class_net, &direntries, good_interface,

2262

2167

alphasort);

2266

2171

ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,

2267

2172

direntries[i]->d_name);

2268

2173

if(ret_errno != 0){

2269

errno = ret_errno;

2270

2174

perror_plus("argz_add");

2271

2175

continue;

2272

2176

}

2277

2181

}

2278

2182

free(direntries);

2279

2183

} else {

2280

if(ret == 0){

2281

free(direntries);

2282

}

2184

free(direntries);

2283

2185

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

2284

2186

exitcode = EXIT_FAILURE;

2285

2187

goto end;

2308

2210

break;

2309

2211

}

2310

2212

bool interface_was_up = interface_is_up(interface);

2311

errno = bring_up_interface(interface, delay);

2213

ret = bring_up_interface(interface, delay);

2312

2214

if(not interface_was_up){

2313

if(errno != 0){

2215

if(ret != 0){

2216

errno = ret;

2314

2217

perror_plus("Failed to bring up interface");

2315

2218

} else {

2316

errno = argz_add(&interfaces_to_take_down,

2317

&interfaces_to_take_down_size,

2318

interface);

2319

if(errno != 0){

2320

perror_plus("argz_add");

2321

}

2219

ret_errno = argz_add(&interfaces_to_take_down,

2220

&interfaces_to_take_down_size,

2221

interface);

2322

2222

}

2323

2223

}

2324

2224

}

2353

2253

goto end;

2354

2254

}

2355

2255

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){

2256

if(mkdtemp(tempdir) == NULL){

2366

2257

perror_plus("mkdtemp");

2367

2258

goto end;

2368

2259

}

2260

tempdir_created = true;

2369

2261

2370

2262

if(quit_now){

2371

2263

goto end;

2446

2338

sleep((unsigned int)retry_interval);

2447

2339

}

2448

2340

2449

if(not quit_now){

2341

if (not quit_now){

2450

2342

exitcode = EXIT_SUCCESS;

2451

2343

}

2452

2344

2507

2399

if(debug){

2508

2400

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

2509

2401

}

2510

2402

2511

2403

ret = avahi_loop_with_timeout(simple_poll,

2512

2404

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

2513

2405

if(debug){

2554

2446

}

2555

2447

}

2556

2448

2557

/* Re-raise privileges */

2449

/* Re-raise priviliges */

2558

2450

{

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

}

2451

raise_privileges();

2452

2453

/* Run network hooks */

2454

run_network_hooks("stop", interfaces_hooks != NULL ?

2455

interfaces_hooks : "", delay);

2456

2457

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

2458

{

2459

char *interface = NULL;

2460

while((interface=argz_next(interfaces_to_take_down,

2461

interfaces_to_take_down_size,

2462

interface))){

2463

ret_errno = take_down_interface(interface);

2464

if(ret_errno != 0){

2465

errno = ret_errno;

2466

perror_plus("Failed to take down interface");

2467

}

2468

}

2469

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

2470

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

2471

" down\n");

2472

}

2473

}

2474

2475

lower_privileges_permanently();

2593

2476

}

2594

2477

2595

2478

free(interfaces_to_take_down);

2596

2479

free(interfaces_hooks);

2597

2480

2598

2481

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

2599

if(tempdir != NULL){

2482

if(tempdir_created){

2600

2483

struct dirent **direntries = NULL;

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

}

2484

struct dirent *direntry = NULL;

2485

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

2486

alphasort);

2487

if (numentries > 0){

2488

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

2489

direntry = direntries[i];

2490

char *fullname = NULL;

2491

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

2492

direntry->d_name);

2493

if(ret < 0){

2494

perror_plus("asprintf");

2495

continue;

2496

}

2497

ret = remove(fullname);

2498

if(ret == -1){

2499

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

2500

strerror(errno));

2501

}

2502

free(fullname);

2637

2503

}

2638

TEMP_FAILURE_RETRY(close(tempdir_fd));

2504

}

2505

2506

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

2507

free(direntries);

2508

if (numentries == -1){

2509

perror_plus("scandir");

2510

}

2511

ret = rmdir(tempdir);

2512

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

2513

perror_plus("rmdir");

2639

2514

}

2640

2515

}

2641

2516