/mandos/release : revision 237.7.195

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

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() */

58

inet_pton(), connect() */

60

59

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

61

60

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

62

61

*/

74

73

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

75

74

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

76

75

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

77

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

76

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

78

77

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

79

78

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

80

79

argp_state, struct argp,

92

91

argz_delete(), argz_append(),

93

92

argz_stringify(), argz_add(),

94

93

argz_count() */

95

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

96

EAI_SYSTEM, gai_strerror() */

97

94

98

95

#ifdef __linux__

99

96

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

141

138

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

142

139

char *connect_to = NULL;

143

140

const char *hookdir = HOOKDIR;

144

int hookdir_fd = -1;

145

141

uid_t uid = 65534;

146

142

gid_t gid = 65534;

147

143

184

180

perror(print_text);

185

181

}

186

182

187

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

183

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

188

184

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

189

185

va_list ap;

190

186

va_start (ap, format);

199

195

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

200

196

* "buffer_length" is how much is already used.

201

197

*/

202

__attribute__((nonnull, warn_unused_result))

203

198

size_t incbuffer(char **buffer, size_t buffer_length,

204

199

size_t buffer_capacity){

205

200

if(buffer_length + BUFFER_SIZE > buffer_capacity){

206

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

207

if(new_buf == NULL){

208

int old_errno = errno;

209

free(*buffer);

210

errno = old_errno;

211

*buffer = NULL;

201

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

202

if(buffer == NULL){

212

203

return 0;

213

204

}

214

*buffer = new_buf;

215

205

buffer_capacity += BUFFER_SIZE;

216

206

}

217

207

return buffer_capacity;

218

208

}

219

209

220

210

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

221

__attribute__((nonnull, warn_unused_result))

222

211

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

223

212

int af, server **current_server){

224

213

int ret;

235

224

perror_plus("strdup");

236

225

return false;

237

226

}

238

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

239

if(ret == -1){

240

perror_plus("clock_gettime");

241

return false;

242

}

243

227

/* Special case of first server */

244

228

if(*current_server == NULL){

245

229

new_server->next = new_server;

246

230

new_server->prev = new_server;

247

231

*current_server = new_server;

232

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

248

233

} else {

249

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

250

234

new_server->next = *current_server;

251

235

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

252

236

new_server->prev->next = new_server;

253

237

(*current_server)->prev = new_server;

254

238

}

239

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

240

if(ret == -1){

241

perror_plus("clock_gettime");

242

return false;

243

}

255

244

return true;

256

245

}

257

246

258

247

/*

259

248

* Initialize GPGME.

260

249

*/

261

__attribute__((nonnull, warn_unused_result))

262

static bool init_gpgme(const char * const seckey,

263

const char * const pubkey,

264

const char * const tempdir,

265

mandos_context *mc){

250

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

251

const char *tempdir, mandos_context *mc){

266

252

gpgme_error_t rc;

267

253

gpgme_engine_info_t engine_info;

268

254

269

255

/*

270

256

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

271

257

*/

272

bool import_key(const char * const filename){

258

bool import_key(const char *filename){

273

259

int ret;

274

260

int fd;

275

261

gpgme_data_t pgp_data;

356

342

* Decrypt OpenPGP data.

357

343

* Returns -1 on error

358

344

*/

359

__attribute__((nonnull, warn_unused_result))

360

345

static ssize_t pgp_packet_decrypt(const char *cryptotext,

361

346

size_t crypto_size,

362

347

char **plaintext,

482

467

return plaintext_length;

483

468

}

484

469

485

__attribute__((warn_unused_result))

486

static const char *safer_gnutls_strerror(int value){

470

static const char * safer_gnutls_strerror(int value){

487

471

const char *ret = gnutls_strerror(value);

488

472

if(ret == NULL)

489

473

ret = "(unknown)";

491

475

}

492

476

493

477

/* GnuTLS log function callback */

494

__attribute__((nonnull))

495

478

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

496

479

const char* string){

497

480

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

498

481

}

499

482

500

__attribute__((nonnull, warn_unused_result))

501

483

static int init_gnutls_global(const char *pubkeyfilename,

502

484

const char *seckeyfilename,

503

485

mandos_context *mc){

577

559

return -1;

578

560

}

579

561

580

__attribute__((nonnull, warn_unused_result))

581

562

static int init_gnutls_session(gnutls_session_t *session,

582

563

mandos_context *mc){

583

564

int ret;

640

621

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

641

622

642

623

/* Called when a Mandos server is found */

643

__attribute__((nonnull, warn_unused_result))

644

624

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

645

625

AvahiIfIndex if_index,

646

626

int af, mandos_context *mc){

647

627

int ret, tcp_sd = -1;

648

628

ssize_t sret;

649

struct sockaddr_storage to;

629

union {

630

struct sockaddr_in in;

631

struct sockaddr_in6 in6;

632

} to;

650

633

char *buffer = NULL;

651

634

char *decrypted_buffer = NULL;

652

635

size_t buffer_length = 0;

733

716

734

717

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

735

718

if(af == AF_INET6){

736

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

737

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);

738

721

} else { /* IPv4 */

739

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

740

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);

741

724

}

742

725

if(ret < 0 ){

743

726

int e = errno;

752

735

goto mandos_end;

753

736

}

754

737

if(af == AF_INET6){

755

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

756

if(IN6_IS_ADDR_LINKLOCAL

757

(&((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

758

748

if(if_index == AVAHI_IF_UNSPEC){

759

749

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

760

750

" incomplete without a network interface\n");

762

752

goto mandos_end;

763

753

}

764

754

/* Set the network interface number as scope */

765

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

755

to.in6.sin6_scope_id = (uint32_t)if_index;

766

756

}

767

757

} else {

768

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

758

to.in.sin_port = htons(port);

769

759

}

770

760

771

761

if(quit_now){

788

778

}

789

779

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

790

780

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

781

const char *pcret;

791

782

if(af == AF_INET6){

792

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

793

sizeof(struct sockaddr_in6),

794

addrstr, sizeof(addrstr), NULL, 0,

795

NI_NUMERICHOST);

783

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

784

sizeof(addrstr));

796

785

} else {

797

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

798

sizeof(struct sockaddr_in),

799

addrstr, sizeof(addrstr), NULL, 0,

800

NI_NUMERICHOST);

786

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

787

sizeof(addrstr));

801

788

}

802

if(ret == EAI_SYSTEM){

803

perror_plus("getnameinfo");

804

} else if(ret != 0) {

805

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

806

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

807

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

}

808

795

}

809

796

}

810

797

814

801

}

815

802

816

803

if(af == AF_INET6){

817

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

818

sizeof(struct sockaddr_in6));

804

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

819

805

} else {

820

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

821

sizeof(struct sockaddr_in));

806

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

822

807

}

823

808

if(ret < 0){

824

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

809

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

825

810

int e = errno;

826

811

perror_plus("connect");

827

812

errno = e;

1042

1027

return retval;

1043

1028

}

1044

1029

1045

__attribute__((nonnull))

1046

1030

static void resolve_callback(AvahiSServiceResolver *r,

1047

1031

AvahiIfIndex interface,

1048

1032

AvahiProtocol proto,

1056

1040

AVAHI_GCC_UNUSED AvahiStringList *txt,

1057

1041

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1058

1042

flags,

1059

void *mc){

1043

void* mc){

1060

1044

if(r == NULL){

1061

1045

return;

1062

1046

}

1115

1099

const char *domain,

1116

1100

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1117

1101

flags,

1118

void *mc){

1102

void* mc){

1119

1103

if(b == NULL){

1120

1104

return;

1121

1105

}

1181

1165

errno = old_errno;

1182

1166

}

1183

1167

1184

__attribute__((nonnull, warn_unused_result))

1185

1168

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

1186

1169

int ret;

1187

1170

error_t ret_errno;

1206

1189

return true;

1207

1190

}

1208

1191

1209

__attribute__((nonnull, warn_unused_result))

1210

1192

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

1211

1193

1212

1194

/* Reject the loopback device */

1254

1236

* corresponds to an acceptable network device.

1255

1237

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

1256

1238

*/

1257

__attribute__((nonnull, warn_unused_result))

1258

1239

int good_interface(const struct dirent *if_entry){

1259

1240

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

1260

1241

return 0;

1278

1259

/*

1279

1260

* This function determines if a network interface is up.

1280

1261

*/

1281

__attribute__((nonnull, warn_unused_result))

1282

1262

bool interface_is_up(const char *interface){

1283

1263

struct ifreq ifr;

1284

1264

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

1295

1275

/*

1296

1276

* This function determines if a network interface is running

1297

1277

*/

1298

__attribute__((nonnull, warn_unused_result))

1299

1278

bool interface_is_running(const char *interface){

1300

1279

struct ifreq ifr;

1301

1280

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

1309

1288

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

1310

1289

}

1311

1290

1312

__attribute__((nonnull, pure, warn_unused_result))

1313

1291

int notdotentries(const struct dirent *direntry){

1314

1292

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

1315

1293

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

1322

1300

}

1323

1301

1324

1302

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

1325

__attribute__((nonnull, warn_unused_result))

1326

1303

int runnable_hook(const struct dirent *direntry){

1327

1304

int ret;

1328

1305

size_t sret;

1336

1313

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

1337

1314

"abcdefghijklmnopqrstuvwxyz"

1338

1315

"0123456789"

1339

"_.-");

1316

"_-");

1340

1317

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

1341

1318

/* Contains non-allowed characters */

1342

1319

if(debug){

1346

1323

return 0;

1347

1324

}

1348

1325

1349

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);

1350

1334

if(ret == -1){

1351

1335

if(debug){

1352

1336

perror_plus("Could not stat hook");

1376

1360

return 1;

1377

1361

}

1378

1362

1379

__attribute__((nonnull, warn_unused_result))

1380

1363

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1381

1364

mandos_context *mc){

1382

1365

int ret;

1386

1369

1387

1370

while(true){

1388

1371

if(mc->current_server == NULL){

1389

if(debug){

1372

if (debug){

1390

1373

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

1391

1374

" No timeout!\n");

1392

1375

}

1393

1376

ret = avahi_simple_poll_iterate(s, -1);

1394

1377

} else {

1395

if(debug){

1378

if (debug){

1396

1379

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

1397

1380

" it, or wait\n");

1398

1381

}

1415

1398

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

1416

1399

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

1417

1400

1418

if(debug){

1401

if (debug){

1419

1402

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

1420

1403

block_time);

1421

1404

}

1443

1426

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

1444

1427

}

1445

1428

if(ret != 0){

1446

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

1429

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

1447

1430

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

1448

1431

}

1449

1432

}

1451

1434

}

1452

1435

1453

1436

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

1454

__attribute__((warn_unused_result))

1455

1437

error_t raise_privileges(void){

1456

1438

error_t old_errno = errno;

1457

1439

error_t ret_errno = 0;

1464

1446

}

1465

1447

1466

1448

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

1467

__attribute__((warn_unused_result))

1468

1449

error_t raise_privileges_permanently(void){

1469

1450

error_t old_errno = errno;

1470

1451

error_t ret_errno = raise_privileges();

1481

1462

}

1482

1463

1483

1464

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

1484

__attribute__((warn_unused_result))

1485

1465

error_t lower_privileges(void){

1486

1466

error_t old_errno = errno;

1487

1467

error_t ret_errno = 0;

1494

1474

}

1495

1475

1496

1476

/* Lower privileges permanently */

1497

__attribute__((warn_unused_result))

1498

1477

error_t lower_privileges_permanently(void){

1499

1478

error_t old_errno = errno;

1500

1479

error_t ret_errno = 0;

1506

1485

return ret_errno;

1507

1486

}

1508

1487

1509

#ifndef O_CLOEXEC

1510

/*

1511

* Based on the example in the GNU LibC manual chapter 13.13 "File

1512

* Descriptor Flags".

1513

| [[info:libc:Descriptor%20Flags][File Descriptor Flags]] |

1514

*/

1515

__attribute__((warn_unused_result))

1516

static int set_cloexec_flag(int fd){

1517

int ret = (int)TEMP_FAILURE_RETRY(fcntl(fd, F_GETFD, 0));

1518

/* If reading the flags failed, return error indication now. */

1519

if(ret < 0){

1520

return ret;

1521

}

1522

/* Store modified flag word in the descriptor. */

1523

return (int)TEMP_FAILURE_RETRY(fcntl(fd, F_SETFD,

1524

ret | FD_CLOEXEC));

1525

}

1526

#endif /* not O_CLOEXEC */

1527

1528

__attribute__((nonnull))

1529

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

1488

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

1530

1489

const float delay){

1531

1490

struct dirent **direntries;

1532

if(hookdir_fd == -1){

1533

hookdir_fd = open(hookdir, O_RDONLY |

1534

#ifdef O_CLOEXEC

1535

O_CLOEXEC

1536

#else /* not O_CLOEXEC */

1537

0

1538

#endif /* not O_CLOEXEC */

1539

);

1540

if(hookdir_fd == -1){

1541

if(errno == ENOENT){

1542

if(debug){

1543

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

1544

" found\n", hookdir);

1545

}

1546

} else {

1547

perror_plus("open");

1548

}

1549

return;

1550

}

1551

#ifndef O_CLOEXEC

1552

if(set_cloexec_flag(hookdir_fd) < 0){

1553

perror_plus("set_cloexec_flag");

1554

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

1555

perror_plus("close");

1556

} else {

1557

hookdir_fd = -1;

1558

}

1559

return;

1560

}

1561

#endif /* not O_CLOEXEC */

1562

}

1563

#ifdef __GLIBC__

1564

#if __GLIBC_PREREQ(2, 15)

1565

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

1566

runnable_hook, alphasort);

1567

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

1568

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

1569

alphasort);

1570

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

1571

#else /* not __GLIBC__ */

1572

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

1573

alphasort);

1574

#endif /* not __GLIBC__ */

1491

struct dirent *direntry;

1492

int ret;

1493

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

1494

alphasort);

1575

1495

if(numhooks == -1){

1576

perror_plus("scandir");

1577

return;

1578

}

1579

struct dirent *direntry;

1580

int ret;

1581

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

1582

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

1583

direntry = direntries[i];

1584

if(debug){

1585

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

1586

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");

1587

1503

}

1588

pid_t hook_pid = fork();

1589

if(hook_pid == 0){

1590

/* Child */

1591

/* Raise privileges */

1592

if(raise_privileges_permanently() != 0){

1593

perror_plus("Failed to raise privileges");

1594

_exit(EX_NOPERM);

1595

}

1596

/* Set group */

1597

errno = 0;

1598

ret = setgid(0);

1599

if(ret == -1){

1600

perror_plus("setgid");

1601

_exit(EX_NOPERM);

1602

}

1603

/* Reset supplementary groups */

1604

errno = 0;

1605

ret = setgroups(0, NULL);

1606

if(ret == -1){

1607

perror_plus("setgroups");

1608

_exit(EX_NOPERM);

1609

}

1610

ret = dup2(devnull, STDIN_FILENO);

1611

if(ret == -1){

1612

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

1613

_exit(EX_OSERR);

1614

}

1615

ret = close(devnull);

1616

if(ret == -1){

1617

perror_plus("close");

1618

_exit(EX_OSERR);

1619

}

1620

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1621

if(ret == -1){

1622

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

1623

_exit(EX_OSERR);

1624

}

1625

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

1626

if(ret == -1){

1627

perror_plus("setenv");

1628

_exit(EX_OSERR);

1629

}

1630

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

1631

if(ret == -1){

1632

perror_plus("setenv");

1633

_exit(EX_OSERR);

1634

}

1635

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

1636

if(ret == -1){

1637

perror_plus("setenv");

1638

_exit(EX_OSERR);

1639

}

1640

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

1641

if(ret == -1){

1642

perror_plus("setenv");

1643

_exit(EX_OSERR);

1644

}

1645

char *delaystring;

1646

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

1647

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){

1648

1511

perror_plus("asprintf");

1649

_exit(EX_OSERR);

1650

}

1651

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

1652

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

}

1653

1570

free(delaystring);

1654

perror_plus("setenv");

1655

_exit(EX_OSERR);

1656

}

1657

free(delaystring);

1658

if(connect_to != NULL){

1659

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

1660

if(ret == -1){

1661

perror_plus("setenv");

1662

_exit(EX_OSERR);

1663

}

1664

}

1665

if(fexecve(hookdir_fd, (char *const [])

1666

{ direntry->d_name, NULL }, environ) == -1){

1667

perror_plus("fexecve");

1668

_exit(EXIT_FAILURE);

1669

}

1670

} else {

1671

int status;

1672

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

1673

perror_plus("waitpid");

1674

continue;

1675

}

1676

if(WIFEXITED(status)){

1677

if(WEXITSTATUS(status) != 0){

1678

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

1679

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

1680

WEXITSTATUS(status));

1681

continue;

1682

}

1683

} else if(WIFSIGNALED(status)){

1684

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

1685

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

1686

WTERMSIG(status));

1687

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

}

1688

1582

} else {

1689

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

1690

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

1691

continue;

1692

}

1693

}

1694

if(debug){

1695

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

1696

direntry->d_name);

1697

}

1698

}

1699

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

1700

perror_plus("close");

1701

} else {

1702

hookdir_fd = -1;

1703

}

1704

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;

1705

1619

}

1706

1620

1707

__attribute__((nonnull, warn_unused_result))

1708

1621

error_t bring_up_interface(const char *const interface,

1709

1622

const float delay){

1623

int sd = -1;

1710

1624

error_t old_errno = errno;

1711

int ret;

1625

error_t ret_errno = 0;

1626

int ret, ret_setflags;

1712

1627

struct ifreq network;

1713

1628

unsigned int if_index = if_nametoindex(interface);

1714

1629

if(if_index == 0){

1723

1638

}

1724

1639

1725

1640

if(not interface_is_up(interface)){

1726

error_t ret_errno = 0, ioctl_errno = 0;

1727

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

1641

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

1728

1642

ret_errno = errno;

1729

1643

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

1730

1644

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

1731

errno = old_errno;

1732

1645

return ret_errno;

1733

1646

}

1734

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

1647

network.ifr_flags |= IFF_UP;

1735

1648

1736

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

1737

if(sd == -1){

1649

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1650

if(sd < 0){

1738

1651

ret_errno = errno;

1739

1652

perror_plus("socket");

1740

1653

errno = old_errno;

1741

1654

return ret_errno;

1742

1655

}

1743

1656

1744

1657

if(quit_now){

1745

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

1746

if(ret == -1){

1747

perror_plus("close");

1748

}

1658

close(sd);

1749

1659

errno = old_errno;

1750

1660

return EINTR;

1751

1661

}

1755

1665

interface);

1756

1666

}

1757

1667

1758

/* Raise privileges */

1759

ret_errno = raise_privileges();

1760

if(ret_errno != 0){

1761

perror_plus("Failed to raise privileges");

1762

}

1668

/* Raise priviliges */

1669

raise_privileges();

1763

1670

1764

1671

#ifdef __linux__

1765

int ret_linux;

1766

bool restore_loglevel = false;

1767

if(ret_errno == 0){

1768

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1769

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

1770

ret_linux = klogctl(8, NULL, 5);

1771

if(ret_linux == -1){

1772

perror_plus("klogctl");

1773

} else {

1774

restore_loglevel = true;

1775

}

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");

1776

1679

}

1777

1680

#endif /* __linux__ */

1778

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

1779

ioctl_errno = errno;

1681

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

1682

ret_errno = errno;

1780

1683

#ifdef __linux__

1781

1684

if(restore_loglevel){

1782

1685

ret_linux = klogctl(7, NULL, 0);

1786

1689

}

1787

1690

#endif /* __linux__ */

1788

1691

1789

/* If raise_privileges() succeeded above */

1790

if(ret_errno == 0){

1791

/* Lower privileges */

1792

ret_errno = lower_privileges();

1793

if(ret_errno != 0){

1794

errno = ret_errno;

1795

perror_plus("Failed to lower privileges");

1796

}

1797

}

1692

/* Lower privileges */

1693

lower_privileges();

1798

1694

1799

1695

/* Close the socket */

1800

1696

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

1803

1699

}

1804

1700

1805

1701

if(ret_setflags == -1){

1806

errno = ioctl_errno;

1702

errno = ret_errno;

1807

1703

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1808

1704

errno = old_errno;

1809

return ioctl_errno;

1705

return ret_errno;

1810

1706

}

1811

1707

} else if(debug){

1812

1708

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

1830

1726

return 0;

1831

1727

}

1832

1728

1833

__attribute__((nonnull, warn_unused_result))

1834

1729

error_t take_down_interface(const char *const interface){

1730

int sd = -1;

1835

1731

error_t old_errno = errno;

1732

error_t ret_errno = 0;

1733

int ret, ret_setflags;

1836

1734

struct ifreq network;

1837

1735

unsigned int if_index = if_nametoindex(interface);

1838

1736

if(if_index == 0){

1841

1739

return ENXIO;

1842

1740

}

1843

1741

if(interface_is_up(interface)){

1844

error_t ret_errno = 0, ioctl_errno = 0;

1845

1742

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

1846

1743

ret_errno = errno;

1847

1744

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

1848

1745

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

1849

errno = old_errno;

1850

1746

return ret_errno;

1851

1747

}

1852

1748

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

1853

1749

1854

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

1855

if(sd == -1){

1750

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1751

if(sd < 0){

1856

1752

ret_errno = errno;

1857

1753

perror_plus("socket");

1858

1754

errno = old_errno;

1864

1760

interface);

1865

1761

}

1866

1762

1867

/* Raise privileges */

1868

ret_errno = raise_privileges();

1869

if(ret_errno != 0){

1870

perror_plus("Failed to raise privileges");

1871

}

1872

1873

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

1874

ioctl_errno = errno;

1875

1876

/* If raise_privileges() succeeded above */

1877

if(ret_errno == 0){

1878

/* Lower privileges */

1879

ret_errno = lower_privileges();

1880

if(ret_errno != 0){

1881

errno = ret_errno;

1882

perror_plus("Failed to lower privileges");

1883

}

1884

}

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();

1885

1771

1886

1772

/* Close the socket */

1887

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

1773

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

1888

1774

if(ret == -1){

1889

1775

perror_plus("close");

1890

1776

}

1891

1777

1892

1778

if(ret_setflags == -1){

1893

errno = ioctl_errno;

1779

errno = ret_errno;

1894

1780

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1895

1781

errno = old_errno;

1896

return ioctl_errno;

1782

return ret_errno;

1897

1783

}

1898

1784

} else if(debug){

1899

1785

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

1907

1793

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

1908

1794

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

1909

1795

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

1910

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

1796

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

1911

1797

.interfaces = NULL, .interfaces_size = 0 };

1912

1798

AvahiSServiceBrowser *sb = NULL;

1913

1799

error_t ret_errno;

1917

1803

int exitcode = EXIT_SUCCESS;

1918

1804

char *interfaces_to_take_down = NULL;

1919

1805

size_t interfaces_to_take_down_size = 0;

1920

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

1921

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

1922

char *tempdir = NULL;

1806

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

1807

bool tempdir_created = false;

1923

1808

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1924

1809

const char *seckey = PATHDIR "/" SECKEY;

1925

1810

const char *pubkey = PATHDIR "/" PUBKEY;

1926

1811

char *interfaces_hooks = NULL;

1812

size_t interfaces_hooks_size = 0;

1927

1813

1928

1814

bool gnutls_initialized = false;

1929

1815

bool gpgme_initialized = false;

2107

1993

/* Work around Debian bug #633582:

2108

1994

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

2109

1995

2110

/* Re-raise privileges */

2111

ret_errno = raise_privileges();

2112

if(ret_errno != 0){

2113

errno = ret_errno;

2114

perror_plus("Failed to raise privileges");

2115

} else {

1996

/* Re-raise priviliges */

1997

if(raise_privileges() == 0){

2116

1998

struct stat st;

2117

1999

2118

2000

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

2158

2040

}

2159

2041

2160

2042

/* Lower privileges */

2161

ret_errno = lower_privileges();

2162

if(ret_errno != 0){

2163

errno = ret_errno;

2164

perror_plus("Failed to lower privileges");

2165

}

2043

lower_privileges();

2166

2044

}

2167

2045

}

2168

2046

2192

2070

goto end;

2193

2071

}

2194

2072

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

2195

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

2196

}

2197

run_network_hooks("start", interfaces_hooks != NULL ?

2198

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

}

2199

2081

}

2200

2082

2201

2083

if(not debug){

2289

2171

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

2290

2172

direntries[i]->d_name);

2291

2173

if(ret_errno != 0){

2292

errno = ret_errno;

2293

2174

perror_plus("argz_add");

2294

2175

continue;

2295

2176

}

2329

2210

break;

2330

2211

}

2331

2212

bool interface_was_up = interface_is_up(interface);

2332

errno = bring_up_interface(interface, delay);

2213

ret = bring_up_interface(interface, delay);

2333

2214

if(not interface_was_up){

2334

if(errno != 0){

2215

if(ret != 0){

2216

errno = ret;

2335

2217

perror_plus("Failed to bring up interface");

2336

2218

} else {

2337

errno = argz_add(&interfaces_to_take_down,

2338

&interfaces_to_take_down_size,

2339

interface);

2340

if(errno != 0){

2341

perror_plus("argz_add");

2342

}

2219

ret_errno = argz_add(&interfaces_to_take_down,

2220

&interfaces_to_take_down_size,

2221

interface);

2343

2222

}

2344

2223

}

2345

2224

}

2374

2253

goto end;

2375

2254

}

2376

2255

2377

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

2378

tempdir = mkdtemp(run_tempdir);

2379

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

2380

if(debug){

2381

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

2382

run_tempdir, old_tempdir);

2383

}

2384

tempdir = mkdtemp(old_tempdir);

2385

}

2386

if(tempdir == NULL){

2256

if(mkdtemp(tempdir) == NULL){

2387

2257

perror_plus("mkdtemp");

2388

2258

goto end;

2389

2259

}

2260

tempdir_created = true;

2390

2261

2391

2262

if(quit_now){

2392

2263

goto end;

2467

2338

sleep((unsigned int)retry_interval);

2468

2339

}

2469

2340

2470

if(not quit_now){

2341

if (not quit_now){

2471

2342

exitcode = EXIT_SUCCESS;

2472

2343

}

2473

2344

2528

2399

if(debug){

2529

2400

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

2530

2401

}

2531

2402

2532

2403

ret = avahi_loop_with_timeout(simple_poll,

2533

2404

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

2534

2405

if(debug){

2575

2446

}

2576

2447

}

2577

2448

2578

/* Re-raise privileges */

2449

/* Re-raise priviliges */

2579

2450

{

2580

ret_errno = raise_privileges();

2581

if(ret_errno != 0){

2582

perror_plus("Failed to raise privileges");

2583

} else {

2584

2585

/* Run network hooks */

2586

run_network_hooks("stop", interfaces_hooks != NULL ?

2587

interfaces_hooks : "", delay);

2588

2589

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

2590

{

2591

char *interface = NULL;

2592

while((interface=argz_next(interfaces_to_take_down,

2593

interfaces_to_take_down_size,

2594

interface))){

2595

ret_errno = take_down_interface(interface);

2596

if(ret_errno != 0){

2597

errno = ret_errno;

2598

perror_plus("Failed to take down interface");

2599

}

2600

}

2601

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

2602

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

2603

" down\n");

2604

}

2605

}

2606

}

2607

2608

ret_errno = lower_privileges_permanently();

2609

if(ret_errno != 0){

2610

perror_plus("Failed to lower privileges permanently");

2611

}

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();

2612

2476

}

2613

2477

2614

2478

free(interfaces_to_take_down);

2615

2479

free(interfaces_hooks);

2616

2480

2617

2481

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

2618

if(tempdir != NULL){

2482

if(tempdir_created){

2619

2483

struct dirent **direntries = NULL;

2620

2484

struct dirent *direntry = NULL;

2621

2485

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

2622

2486

alphasort);

2623

if(numentries > 0){

2487

if (numentries > 0){

2624

2488

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

2625

2489

direntry = direntries[i];

2626

2490

char *fullname = NULL;

2638

2502

free(fullname);

2639

2503

}

2640

2504

}

2641

2505

2642

2506

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

2643

2507

free(direntries);

2644

if(numentries == -1){

2508

if (numentries == -1){

2645

2509

perror_plus("scandir");

2646

2510

}

2647

2511

ret = rmdir(tempdir);