/mandos/trunk : revision 237.4.35

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

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

740

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

741

-Wunreachable-code*/

758

742

if(if_index == AVAHI_IF_UNSPEC){

759

743

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

760

744

" incomplete without a network interface\n");

762

746

goto mandos_end;

763

747

}

764

748

/* Set the network interface number as scope */

765

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

749

to.in6.sin6_scope_id = (uint32_t)if_index;

766

750

}

767

751

} else {

768

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

752

to.in.sin_port = htons(port); /* Spurious warnings from

753

-Wconversion and

754

-Wunreachable-code */

769

755

}

770

756

771

757

if(quit_now){

788

774

}

789

775

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

790

776

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

777

const char *pcret;

791

778

if(af == AF_INET6){

792

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

793

sizeof(struct sockaddr_in6),

794

addrstr, sizeof(addrstr), NULL, 0,

795

NI_NUMERICHOST);

779

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

780

sizeof(addrstr));

796

781

} else {

797

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

798

sizeof(struct sockaddr_in),

799

addrstr, sizeof(addrstr), NULL, 0,

800

NI_NUMERICHOST);

782

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

783

sizeof(addrstr));

801

784

}

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);

785

if(pcret == NULL){

786

perror_plus("inet_ntop");

787

} else {

788

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

789

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

790

}

808

791

}

809

792

}

810

793

814

797

}

815

798

816

799

if(af == AF_INET6){

817

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

818

sizeof(struct sockaddr_in6));

800

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

819

801

} else {

820

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

821

sizeof(struct sockaddr_in));

802

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

822

803

}

823

804

if(ret < 0){

824

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

805

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

825

806

int e = errno;

826

807

perror_plus("connect");

827

808

errno = e;

1042

1023

return retval;

1043

1024

}

1044

1025

1045

__attribute__((nonnull))

1046

1026

static void resolve_callback(AvahiSServiceResolver *r,

1047

1027

AvahiIfIndex interface,

1048

1028

AvahiProtocol proto,

1056

1036

AVAHI_GCC_UNUSED AvahiStringList *txt,

1057

1037

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1058

1038

flags,

1059

void *mc){

1039

void* mc){

1060

1040

if(r == NULL){

1061

1041

return;

1062

1042

}

1115

1095

const char *domain,

1116

1096

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1117

1097

flags,

1118

void *mc){

1098

void* mc){

1119

1099

if(b == NULL){

1120

1100

return;

1121

1101

}

1181

1161

errno = old_errno;

1182

1162

}

1183

1163

1184

__attribute__((nonnull, warn_unused_result))

1185

1164

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

1186

1165

int ret;

1187

1166

error_t ret_errno;

1206

1185

return true;

1207

1186

}

1208

1187

1209

__attribute__((nonnull, warn_unused_result))

1210

1188

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

1211

1189

1212

1190

/* Reject the loopback device */

1254

1232

* corresponds to an acceptable network device.

1255

1233

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

1256

1234

*/

1257

__attribute__((nonnull, warn_unused_result))

1258

1235

int good_interface(const struct dirent *if_entry){

1259

1236

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

1260

1237

return 0;

1278

1255

/*

1279

1256

* This function determines if a network interface is up.

1280

1257

*/

1281

__attribute__((nonnull, warn_unused_result))

1282

1258

bool interface_is_up(const char *interface){

1283

1259

struct ifreq ifr;

1284

1260

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

1295

1271

/*

1296

1272

* This function determines if a network interface is running

1297

1273

*/

1298

__attribute__((nonnull, warn_unused_result))

1299

1274

bool interface_is_running(const char *interface){

1300

1275

struct ifreq ifr;

1301

1276

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

1309

1284

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

1310

1285

}

1311

1286

1312

__attribute__((nonnull, pure, warn_unused_result))

1313

1287

int notdotentries(const struct dirent *direntry){

1314

1288

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

1315

1289

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

1322

1296

}

1323

1297

1324

1298

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

1325

__attribute__((nonnull, warn_unused_result))

1326

1299

int runnable_hook(const struct dirent *direntry){

1327

1300

int ret;

1328

1301

size_t sret;

1336

1309

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

1337

1310

"abcdefghijklmnopqrstuvwxyz"

1338

1311

"0123456789"

1339

"_.-");

1312

"_-");

1340

1313

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

1341

1314

/* Contains non-allowed characters */

1342

1315

if(debug){

1346

1319

return 0;

1347

1320

}

1348

1321

1349

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

1322

char *fullname = NULL;

1323

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

1324

if(ret < 0){

1325

perror_plus("asprintf");

1326

return 0;

1327

}

1328

1329

ret = stat(fullname, &st);

1350

1330

if(ret == -1){

1351

1331

if(debug){

1352

1332

perror_plus("Could not stat hook");

1376

1356

return 1;

1377

1357

}

1378

1358

1379

__attribute__((nonnull, warn_unused_result))

1380

1359

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1381

1360

mandos_context *mc){

1382

1361

int ret;

1386

1365

1387

1366

while(true){

1388

1367

if(mc->current_server == NULL){

1389

if(debug){

1368

if (debug){

1390

1369

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

1391

1370

" No timeout!\n");

1392

1371

}

1393

1372

ret = avahi_simple_poll_iterate(s, -1);

1394

1373

} else {

1395

if(debug){

1374

if (debug){

1396

1375

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

1397

1376

" it, or wait\n");

1398

1377

}

1415

1394

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

1416

1395

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

1417

1396

1418

if(debug){

1397

if (debug){

1419

1398

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

1420

1399

block_time);

1421

1400

}

1443

1422

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

1444

1423

}

1445

1424

if(ret != 0){

1446

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

1425

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

1447

1426

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

1448

1427

}

1449

1428

}

1451

1430

}

1452

1431

1453

1432

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

1454

__attribute__((warn_unused_result))

1455

1433

error_t raise_privileges(void){

1456

1434

error_t old_errno = errno;

1457

1435

error_t ret_errno = 0;

1464

1442

}

1465

1443

1466

1444

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

1467

__attribute__((warn_unused_result))

1468

1445

error_t raise_privileges_permanently(void){

1469

1446

error_t old_errno = errno;

1470

1447

error_t ret_errno = raise_privileges();

1481

1458

}

1482

1459

1483

1460

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

1484

__attribute__((warn_unused_result))

1485

1461

error_t lower_privileges(void){

1486

1462

error_t old_errno = errno;

1487

1463

error_t ret_errno = 0;

1494

1470

}

1495

1471

1496

1472

/* Lower privileges permanently */

1497

__attribute__((warn_unused_result))

1498

1473

error_t lower_privileges_permanently(void){

1499

1474

error_t old_errno = errno;

1500

1475

error_t ret_errno = 0;

1506

1481

return ret_errno;

1507

1482

}

1508

1483

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,

1484

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

1530

1485

const float delay){

1531

1486

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__ */

1487

struct dirent *direntry;

1488

int ret;

1489

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

1490

alphasort);

1575

1491

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);

1492

if(errno == ENOENT){

1493

if(debug){

1494

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

1495

" found\n", hookdir);

1496

}

1497

} else {

1498

perror_plus("scandir");

1587

1499

}

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){

1500

} else {

1501

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

1502

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

1503

direntry = direntries[i];

1504

char *fullname = NULL;

1505

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

1506

if(ret < 0){

1648

1507

perror_plus("asprintf");

1649

_exit(EX_OSERR);

1650

}

1651

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

1652

if(ret == -1){

1508

continue;

1509

}

1510

if(debug){

1511

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

1512

direntry->d_name);

1513

}

1514

pid_t hook_pid = fork();

1515

if(hook_pid == 0){

1516

/* Child */

1517

/* Raise privileges */

1518

raise_privileges_permanently();

1519

/* Set group */

1520

errno = 0;

1521

ret = setgid(0);

1522

if(ret == -1){

1523

perror_plus("setgid");

1524

}

1525

/* Reset supplementary groups */

1526

errno = 0;

1527

ret = setgroups(0, NULL);

1528

if(ret == -1){

1529

perror_plus("setgroups");

1530

}

1531

dup2(devnull, STDIN_FILENO);

1532

close(devnull);

1533

dup2(STDERR_FILENO, STDOUT_FILENO);

1534

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

1535

if(ret == -1){

1536

perror_plus("setenv");

1537

_exit(EX_OSERR);

1538

}

1539

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

1540

if(ret == -1){

1541

perror_plus("setenv");

1542

_exit(EX_OSERR);

1543

}

1544

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

1545

if(ret == -1){

1546

perror_plus("setenv");

1547

_exit(EX_OSERR);

1548

}

1549

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

1550

if(ret == -1){

1551

perror_plus("setenv");

1552

_exit(EX_OSERR);

1553

}

1554

char *delaystring;

1555

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

1556

if(ret == -1){

1557

perror_plus("asprintf");

1558

_exit(EX_OSERR);

1559

}

1560

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

1561

if(ret == -1){

1562

free(delaystring);

1563

perror_plus("setenv");

1564

_exit(EX_OSERR);

1565

}

1653

1566

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;

1567

if(connect_to != NULL){

1568

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

1569

if(ret == -1){

1570

perror_plus("setenv");

1571

_exit(EX_OSERR);

1572

}

1573

}

1574

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

1575

perror_plus("execl");

1576

_exit(EXIT_FAILURE);

1577

}

1688

1578

} 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);

1579

int status;

1580

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

1581

perror_plus("waitpid");

1582

free(fullname);

1583

continue;

1584

}

1585

if(WIFEXITED(status)){

1586

if(WEXITSTATUS(status) != 0){

1587

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

1588

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

1589

WEXITSTATUS(status));

1590

free(fullname);

1591

continue;

1592

}

1593

} else if(WIFSIGNALED(status)){

1594

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

1595

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

1596

WTERMSIG(status));

1597

free(fullname);

1598

continue;

1599

} else {

1600

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

1601

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

1602

free(fullname);

1603

continue;

1604

}

1605

}

1606

free(fullname);

1607

if(debug){

1608

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

1609

direntry->d_name);

1610

}

1611

}

1612

close(devnull);

1613

}

1614

return true;

1705

1615

}

1706

1616

1707

__attribute__((nonnull, warn_unused_result))

1708

1617

error_t bring_up_interface(const char *const interface,

1709

1618

const float delay){

1619

int sd = -1;

1710

1620

error_t old_errno = errno;

1711

int ret;

1621

error_t ret_errno = 0;

1622

int ret, ret_setflags;

1712

1623

struct ifreq network;

1713

1624

unsigned int if_index = if_nametoindex(interface);

1714

1625

if(if_index == 0){

1723

1634

}

1724

1635

1725

1636

if(not interface_is_up(interface)){

1726

error_t ret_errno = 0, ioctl_errno = 0;

1727

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

1637

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

1728

1638

ret_errno = errno;

1729

1639

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

1730

1640

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

1731

errno = old_errno;

1732

1641

return ret_errno;

1733

1642

}

1734

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

1643

network.ifr_flags |= IFF_UP;

1735

1644

1736

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

1737

if(sd == -1){

1645

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1646

if(sd < 0){

1738

1647

ret_errno = errno;

1739

1648

perror_plus("socket");

1740

1649

errno = old_errno;

1741

1650

return ret_errno;

1742

1651

}

1743

1652

1744

1653

if(quit_now){

1745

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

1746

if(ret == -1){

1747

perror_plus("close");

1748

}

1654

close(sd);

1749

1655

errno = old_errno;

1750

1656

return EINTR;

1751

1657

}

1755

1661

interface);

1756

1662

}

1757

1663

1758

/* Raise privileges */

1759

ret_errno = raise_privileges();

1760

if(ret_errno != 0){

1761

perror_plus("Failed to raise privileges");

1762

}

1664

/* Raise priviliges */

1665

raise_privileges();

1763

1666

1764

1667

#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

}

1668

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1669

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

1670

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

1671

bool restore_loglevel = true;

1672

if(ret_linux == -1){

1673

restore_loglevel = false;

1674

perror_plus("klogctl");

1776

1675

}

1777

1676

#endif /* __linux__ */

1778

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

1779

ioctl_errno = errno;

1677

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

1678

ret_errno = errno;

1780

1679

#ifdef __linux__

1781

1680

if(restore_loglevel){

1782

1681

ret_linux = klogctl(7, NULL, 0);

1786

1685

}

1787

1686

#endif /* __linux__ */

1788

1687

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

}

1688

/* Lower privileges */

1689

lower_privileges();

1798

1690

1799

1691

/* Close the socket */

1800

1692

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

1803

1695

}

1804

1696

1805

1697

if(ret_setflags == -1){

1806

errno = ioctl_errno;

1698

errno = ret_errno;

1807

1699

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1808

1700

errno = old_errno;

1809

return ioctl_errno;

1701

return ret_errno;

1810

1702

}

1811

1703

} else if(debug){

1812

1704

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

1830

1722

return 0;

1831

1723

}

1832

1724

1833

__attribute__((nonnull, warn_unused_result))

1834

1725

error_t take_down_interface(const char *const interface){

1726

int sd = -1;

1835

1727

error_t old_errno = errno;

1728

error_t ret_errno = 0;

1729

int ret, ret_setflags;

1836

1730

struct ifreq network;

1837

1731

unsigned int if_index = if_nametoindex(interface);

1838

1732

if(if_index == 0){

1841

1735

return ENXIO;

1842

1736

}

1843

1737

if(interface_is_up(interface)){

1844

error_t ret_errno = 0, ioctl_errno = 0;

1845

1738

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

1846

1739

ret_errno = errno;

1847

1740

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

1848

1741

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

1849

errno = old_errno;

1850

1742

return ret_errno;

1851

1743

}

1852

1744

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

1853

1745

1854

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

1855

if(sd == -1){

1746

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1747

if(sd < 0){

1856

1748

ret_errno = errno;

1857

1749

perror_plus("socket");

1858

1750

errno = old_errno;

1864

1756

interface);

1865

1757

}

1866

1758

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

}

1759

/* Raise priviliges */

1760

raise_privileges();

1761

1762

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

1763

ret_errno = errno;

1764

1765

/* Lower privileges */

1766

lower_privileges();

1885

1767

1886

1768

/* Close the socket */

1887

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

1769

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

1888

1770

if(ret == -1){

1889

1771

perror_plus("close");

1890

1772

}

1891

1773

1892

1774

if(ret_setflags == -1){

1893

errno = ioctl_errno;

1775

errno = ret_errno;

1894

1776

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1895

1777

errno = old_errno;

1896

return ioctl_errno;

1778

return ret_errno;

1897

1779

}

1898

1780

} else if(debug){

1899

1781

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

1907

1789

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

1908

1790

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

1909

1791

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

1910

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

1792

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

1911

1793

.interfaces = NULL, .interfaces_size = 0 };

1912

1794

AvahiSServiceBrowser *sb = NULL;

1913

1795

error_t ret_errno;

1917

1799

int exitcode = EXIT_SUCCESS;

1918

1800

char *interfaces_to_take_down = NULL;

1919

1801

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;

1802

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

1803

bool tempdir_created = false;

1923

1804

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1924

1805

const char *seckey = PATHDIR "/" SECKEY;

1925

1806

const char *pubkey = PATHDIR "/" PUBKEY;

1926

1807

char *interfaces_hooks = NULL;

1808

size_t interfaces_hooks_size = 0;

1927

1809

1928

1810

bool gnutls_initialized = false;

1929

1811

bool gpgme_initialized = false;

2107

1989

/* Work around Debian bug #633582:

2108

1990

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

2109

1991

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 {

1992

/* Re-raise priviliges */

1993

if(raise_privileges() == 0){

2116

1994

struct stat st;

2117

1995

2118

1996

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

2158

2036

}

2159

2037

2160

2038

/* Lower privileges */

2161

ret_errno = lower_privileges();

2162

if(ret_errno != 0){

2163

errno = ret_errno;

2164

perror_plus("Failed to lower privileges");

2165

}

2039

lower_privileges();

2166

2040

}

2167

2041

}

2168

2042

2192

2066

goto end;

2193

2067

}

2194

2068

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);

2069

interfaces_hooks_size = mc.interfaces_size;

2070

argz_stringify(interfaces_hooks, interfaces_hooks_size,

2071

(int)',');

2072

}

2073

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

2074

interfaces_hooks : "", delay)){

2075

goto end;

2076

}

2199

2077

}

2200

2078

2201

2079

if(not debug){

2289

2167

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

2290

2168

direntries[i]->d_name);

2291

2169

if(ret_errno != 0){

2292

errno = ret_errno;

2293

2170

perror_plus("argz_add");

2294

2171

continue;

2295

2172

}

2329

2206

break;

2330

2207

}

2331

2208

bool interface_was_up = interface_is_up(interface);

2332

errno = bring_up_interface(interface, delay);

2209

ret = bring_up_interface(interface, delay);

2333

2210

if(not interface_was_up){

2334

if(errno != 0){

2211

if(ret != 0){

2212

errno = ret;

2335

2213

perror_plus("Failed to bring up interface");

2336

2214

} 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

}

2215

ret_errno = argz_add(&interfaces_to_take_down,

2216

&interfaces_to_take_down_size,

2217

interface);

2343

2218

}

2344

2219

}

2345

2220

}

2374

2249

goto end;

2375

2250

}

2376

2251

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){

2252

if(mkdtemp(tempdir) == NULL){

2387

2253

perror_plus("mkdtemp");

2388

2254

goto end;

2389

2255

}

2256

tempdir_created = true;

2390

2257

2391

2258

if(quit_now){

2392

2259

goto end;

2467

2334

sleep((unsigned int)retry_interval);

2468

2335

}

2469

2336

2470

if(not quit_now){

2337

if (not quit_now){

2471

2338

exitcode = EXIT_SUCCESS;

2472

2339

}

2473

2340

2528

2395

if(debug){

2529

2396

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

2530

2397

}

2531

2398

2532

2399

ret = avahi_loop_with_timeout(simple_poll,

2533

2400

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

2534

2401

if(debug){

2575

2442

}

2576

2443

}

2577

2444

2578

/* Re-raise privileges */

2445

/* Re-raise priviliges */

2579

2446

{

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

}

2447

raise_privileges();

2448

2449

/* Run network hooks */

2450

run_network_hooks("stop", interfaces_hooks != NULL ?

2451

interfaces_hooks : "", delay);

2452

2453

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

2454

{

2455

char *interface = NULL;

2456

while((interface=argz_next(interfaces_to_take_down,

2457

interfaces_to_take_down_size,

2458

interface))){

2459

ret_errno = take_down_interface(interface);

2460

if(ret_errno != 0){

2461

errno = ret_errno;

2462

perror_plus("Failed to take down interface");

2463

}

2464

}

2465

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

2466

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

2467

" down\n");

2468

}

2469

}

2470

2471

lower_privileges_permanently();

2612

2472

}

2613

2473

2614

2474

free(interfaces_to_take_down);

2615

2475

free(interfaces_hooks);

2616

2476

2617

2477

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

2618

if(tempdir != NULL){

2478

if(tempdir_created){

2619

2479

struct dirent **direntries = NULL;

2620

2480

struct dirent *direntry = NULL;

2621

2481

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

2622

2482

alphasort);

2623

if(numentries > 0){

2483

if (numentries > 0){

2624

2484

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

2625

2485

direntry = direntries[i];

2626

2486

char *fullname = NULL;

2638

2498

free(fullname);

2639

2499

}

2640

2500

}

2641

2501

2642

2502

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

2643

2503

free(direntries);

2644

if(numentries == -1){

2504

if (numentries == -1){

2645

2505

perror_plus("scandir");

2646

2506

}

2647

2507

ret = rmdir(tempdir);