/mandos/release : revision 237.7.240

9

* "browse_callback", and parts of "main".

10

*

11

* Everything else is

12

13

12

13

14

*

15

* This program is free software: you can redistribute it and/or

16

* modify it under the terms of the GNU General Public License as

32

/* Needed by GPGME, specifically gpgme_data_seek() */

33

#ifndef _LARGEFILE_SOURCE

34

#define _LARGEFILE_SOURCE

35

#endif

35

#endif /* not _LARGEFILE_SOURCE */

36

#ifndef _FILE_OFFSET_BITS

37

#define _FILE_OFFSET_BITS 64

38

#endif

38

#endif /* not _FILE_OFFSET_BITS */

39

40

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

41

55

opendir(), DIR */

56

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

57

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

58

inet_pton(), connect() */

58

inet_pton(), connect(),

59

getnameinfo() */

59

60

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

60

61

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

61

62

*/

73

74

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

74

75

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

75

76

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

76

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

77

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

77

78

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

78

79

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

79

80

argp_state, struct argp,

91

92

argz_delete(), argz_append(),

92

93

argz_stringify(), argz_add(),

93

94

argz_count() */

95

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

96

EAI_SYSTEM, gai_strerror() */

94

97

95

98

#ifdef __linux__

96

99

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

138

141

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

139

142

char *connect_to = NULL;

140

143

const char *hookdir = HOOKDIR;

144

int hookdir_fd = -1;

141

145

uid_t uid = 65534;

142

146

gid_t gid = 65534;

143

147

180

184

perror(print_text);

181

185

}

182

186

183

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

187

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

184

188

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

185

189

va_list ap;

186

190

va_start (ap, format);

195

199

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

196

200

* "buffer_length" is how much is already used.

197

201

*/

202

__attribute__((nonnull, warn_unused_result))

198

203

size_t incbuffer(char **buffer, size_t buffer_length,

199

204

size_t buffer_capacity){

200

205

if(buffer_length + BUFFER_SIZE > buffer_capacity){

201

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

202

if(buffer == NULL){

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;

203

212

return 0;

204

213

}

214

*buffer = new_buf;

205

215

buffer_capacity += BUFFER_SIZE;

206

216

}

207

217

return buffer_capacity;

208

218

}

209

219

210

220

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

221

__attribute__((nonnull, warn_unused_result))

211

222

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

212

223

int af, server **current_server){

213

224

int ret;

224

235

perror_plus("strdup");

225

236

return false;

226

237

}

238

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

239

if(ret == -1){

240

perror_plus("clock_gettime");

241

return false;

242

}

227

243

/* Special case of first server */

228

244

if(*current_server == NULL){

229

245

new_server->next = new_server;

230

246

new_server->prev = new_server;

231

247

*current_server = new_server;

232

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

233

248

} else {

249

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

234

250

new_server->next = *current_server;

235

251

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

236

252

new_server->prev->next = new_server;

237

253

(*current_server)->prev = new_server;

238

254

}

239

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

240

if(ret == -1){

241

perror_plus("clock_gettime");

242

return false;

243

}

244

255

return true;

245

256

}

246

257

247

258

/*

248

259

* Initialize GPGME.

249

260

*/

250

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

251

const char *tempdir, mandos_context *mc){

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){

252

266

gpgme_error_t rc;

253

267

gpgme_engine_info_t engine_info;

254

268

255

269

/*

256

270

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

257

271

*/

258

bool import_key(const char *filename){

272

bool import_key(const char * const filename){

259

273

int ret;

260

274

int fd;

261

275

gpgme_data_t pgp_data;

342

356

* Decrypt OpenPGP data.

343

357

* Returns -1 on error

344

358

*/

359

__attribute__((nonnull, warn_unused_result))

345

360

static ssize_t pgp_packet_decrypt(const char *cryptotext,

346

361

size_t crypto_size,

347

362

char **plaintext,

467

482

return plaintext_length;

468

483

}

469

484

470

static const char * safer_gnutls_strerror(int value){

485

__attribute__((warn_unused_result))

486

static const char *safer_gnutls_strerror(int value){

471

487

const char *ret = gnutls_strerror(value);

472

488

if(ret == NULL)

473

489

ret = "(unknown)";

475

491

}

476

492

477

493

/* GnuTLS log function callback */

494

__attribute__((nonnull))

478

495

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

479

496

const char* string){

480

497

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

481

498

}

482

499

500

__attribute__((nonnull, warn_unused_result))

483

501

static int init_gnutls_global(const char *pubkeyfilename,

484

502

const char *seckeyfilename,

485

503

mandos_context *mc){

559

577

return -1;

560

578

}

561

579

580

__attribute__((nonnull, warn_unused_result))

562

581

static int init_gnutls_session(gnutls_session_t *session,

563

582

mandos_context *mc){

564

583

int ret;

621

640

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

622

641

623

642

/* Called when a Mandos server is found */

643

__attribute__((nonnull, warn_unused_result))

624

644

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

625

645

AvahiIfIndex if_index,

626

646

int af, mandos_context *mc){

627

647

int ret, tcp_sd = -1;

628

648

ssize_t sret;

629

union {

630

struct sockaddr_in in;

631

struct sockaddr_in6 in6;

632

} to;

649

struct sockaddr_storage to;

633

650

char *buffer = NULL;

634

651

char *decrypted_buffer = NULL;

635

652

size_t buffer_length = 0;

716

733

717

734

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

718

735

if(af == AF_INET6){

719

to.in6.sin6_family = (sa_family_t)af;

720

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

736

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

737

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

721

738

} else { /* IPv4 */

722

to.in.sin_family = (sa_family_t)af;

723

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

739

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

740

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

724

741

}

725

742

if(ret < 0 ){

726

743

int e = errno;

735

752

goto mandos_end;

736

753

}

737

754

if(af == AF_INET6){

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

755

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

756

if(IN6_IS_ADDR_LINKLOCAL

757

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

748

758

if(if_index == AVAHI_IF_UNSPEC){

749

759

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

750

760

" incomplete without a network interface\n");

752

762

goto mandos_end;

753

763

}

754

764

/* Set the network interface number as scope */

755

to.in6.sin6_scope_id = (uint32_t)if_index;

765

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

756

766

}

757

767

} else {

758

to.in.sin_port = htons(port);

768

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

759

769

}

760

770

761

771

if(quit_now){

778

788

}

779

789

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

780

790

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

781

const char *pcret;

782

791

if(af == AF_INET6){

783

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

784

sizeof(addrstr));

792

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

793

sizeof(struct sockaddr_in6),

794

addrstr, sizeof(addrstr), NULL, 0,

795

NI_NUMERICHOST);

785

796

} else {

786

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

787

sizeof(addrstr));

797

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

798

sizeof(struct sockaddr_in),

799

addrstr, sizeof(addrstr), NULL, 0,

800

NI_NUMERICHOST);

788

801

}

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

}

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);

795

808

}

796

809

}

797

810

801

814

}

802

815

803

816

if(af == AF_INET6){

804

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

817

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

818

sizeof(struct sockaddr_in6));

805

819

} else {

806

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

820

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

821

sizeof(struct sockaddr_in));

807

822

}

808

823

if(ret < 0){

809

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

824

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

810

825

int e = errno;

811

826

perror_plus("connect");

812

827

errno = e;

1027

1042

return retval;

1028

1043

}

1029

1044

1045

__attribute__((nonnull))

1030

1046

static void resolve_callback(AvahiSServiceResolver *r,

1031

1047

AvahiIfIndex interface,

1032

1048

AvahiProtocol proto,

1040

1056

AVAHI_GCC_UNUSED AvahiStringList *txt,

1041

1057

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1042

1058

flags,

1043

void* mc){

1059

void *mc){

1044

1060

if(r == NULL){

1045

1061

return;

1046

1062

}

1099

1115

const char *domain,

1100

1116

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1101

1117

flags,

1102

void* mc){

1118

void *mc){

1103

1119

if(b == NULL){

1104

1120

return;

1105

1121

}

1165

1181

errno = old_errno;

1166

1182

}

1167

1183

1184

__attribute__((nonnull, warn_unused_result))

1168

1185

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

1169

1186

int ret;

1170

1187

error_t ret_errno;

1189

1206

return true;

1190

1207

}

1191

1208

1209

__attribute__((nonnull, warn_unused_result))

1192

1210

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

1193

1211

1194

1212

/* Reject the loopback device */

1236

1254

* corresponds to an acceptable network device.

1237

1255

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

1238

1256

*/

1257

__attribute__((nonnull, warn_unused_result))

1239

1258

int good_interface(const struct dirent *if_entry){

1240

1259

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

1241

1260

return 0;

1259

1278

/*

1260

1279

* This function determines if a network interface is up.

1261

1280

*/

1281

__attribute__((nonnull, warn_unused_result))

1262

1282

bool interface_is_up(const char *interface){

1263

1283

struct ifreq ifr;

1264

1284

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

1275

1295

/*

1276

1296

* This function determines if a network interface is running

1277

1297

*/

1298

__attribute__((nonnull, warn_unused_result))

1278

1299

bool interface_is_running(const char *interface){

1279

1300

struct ifreq ifr;

1280

1301

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

1288

1309

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

1289

1310

}

1290

1311

1312

__attribute__((nonnull, pure, warn_unused_result))

1291

1313

int notdotentries(const struct dirent *direntry){

1292

1314

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

1293

1315

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

1300

1322

}

1301

1323

1302

1324

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

1325

__attribute__((nonnull, warn_unused_result))

1303

1326

int runnable_hook(const struct dirent *direntry){

1304

1327

int ret;

1305

1328

size_t sret;

1313

1336

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

1314

1337

"abcdefghijklmnopqrstuvwxyz"

1315

1338

"0123456789"

1316

"_-");

1339

"_.-");

1317

1340

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

1318

1341

/* Contains non-allowed characters */

1319

1342

if(debug){

1337

1360

}

1338

1361

return 0;

1339

1362

}

1363

free(fullname);

1340

1364

if(not (S_ISREG(st.st_mode))){

1341

1365

/* Not a regular file */

1342

1366

if(debug){

1360

1384

return 1;

1361

1385

}

1362

1386

1387

__attribute__((nonnull, warn_unused_result))

1363

1388

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1364

1389

mandos_context *mc){

1365

1390

int ret;

1369

1394

1370

1395

while(true){

1371

1396

if(mc->current_server == NULL){

1372

if (debug){

1397

if(debug){

1373

1398

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

1374

1399

" No timeout!\n");

1375

1400

}

1376

1401

ret = avahi_simple_poll_iterate(s, -1);

1377

1402

} else {

1378

if (debug){

1403

if(debug){

1379

1404

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

1380

1405

" it, or wait\n");

1381

1406

}

1398

1423

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

1399

1424

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

1400

1425

1401

if (debug){

1426

if(debug){

1402

1427

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

1403

1428

block_time);

1404

1429

}

1426

1451

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

1427

1452

}

1428

1453

if(ret != 0){

1429

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

1454

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

1430

1455

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

1431

1456

}

1432

1457

}

1434

1459

}

1435

1460

1436

1461

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

1462

__attribute__((warn_unused_result))

1437

1463

error_t raise_privileges(void){

1438

1464

error_t old_errno = errno;

1439

1465

error_t ret_errno = 0;

1446

1472

}

1447

1473

1448

1474

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

1475

__attribute__((warn_unused_result))

1449

1476

error_t raise_privileges_permanently(void){

1450

1477

error_t old_errno = errno;

1451

1478

error_t ret_errno = raise_privileges();

1462

1489

}

1463

1490

1464

1491

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

1492

__attribute__((warn_unused_result))

1465

1493

error_t lower_privileges(void){

1466

1494

error_t old_errno = errno;

1467

1495

error_t ret_errno = 0;

1474

1502

}

1475

1503

1476

1504

/* Lower privileges permanently */

1505

__attribute__((warn_unused_result))

1477

1506

error_t lower_privileges_permanently(void){

1478

1507

error_t old_errno = errno;

1479

1508

error_t ret_errno = 0;

1485

1514

return ret_errno;

1486

1515

}

1487

1516

1488

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

1517

#ifndef O_CLOEXEC

1518

/*

1519

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

1520

* Descriptor Flags".

1521

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

1522

*/

1523

__attribute__((warn_unused_result))

1524

static int set_cloexec_flag(int fd){

1525

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

1526

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

1527

if(ret < 0){

1528

return ret;

1529

}

1530

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

1531

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

1532

ret | FD_CLOEXEC));

1533

}

1534

#endif /* not O_CLOEXEC */

1535

1536

__attribute__((nonnull))

1537

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

1489

1538

const float delay){

1490

1539

struct dirent **direntries;

1540

if(hookdir_fd == -1){

1541

hookdir_fd = open(hookdir, O_RDONLY |

1542

#ifdef O_CLOEXEC

1543

O_CLOEXEC

1544

#else /* not O_CLOEXEC */

1545

0

1546

#endif /* not O_CLOEXEC */

1547

);

1548

if(hookdir_fd == -1){

1549

if(errno == ENOENT){

1550

if(debug){

1551

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

1552

" found\n", hookdir);

1553

}

1554

} else {

1555

perror_plus("open");

1556

}

1557

return;

1558

}

1559

#ifndef O_CLOEXEC

1560

if(set_cloexec_flag(hookdir_fd) < 0){

1561

perror_plus("set_cloexec_flag");

1562

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

1563

perror_plus("close");

1564

} else {

1565

hookdir_fd = -1;

1566

}

1567

return;

1568

}

1569

#endif /* not O_CLOEXEC */

1570

}

1571

#ifdef __GLIBC__

1572

#if __GLIBC_PREREQ(2, 15)

1573

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

1574

runnable_hook, alphasort);

1575

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

1576

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

1577

alphasort);

1578

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

1579

#else /* not __GLIBC__ */

1580

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

1581

alphasort);

1582

#endif /* not __GLIBC__ */

1583

if(numhooks == -1){

1584

perror_plus("scandir");

1585

return;

1586

}

1491

1587

struct dirent *direntry;

1492

1588

int ret;

1493

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

1494

alphasort);

1495

if(numhooks == -1){

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");

1589

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

1590

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

1591

direntry = direntries[i];

1592

if(debug){

1593

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

1594

direntry->d_name);

1503

1595

}

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){

1596

pid_t hook_pid = fork();

1597

if(hook_pid == 0){

1598

/* Child */

1599

/* Raise privileges */

1600

if(raise_privileges_permanently() != 0){

1601

perror_plus("Failed to raise privileges");

1602

_exit(EX_NOPERM);

1603

}

1604

/* Set group */

1605

errno = 0;

1606

ret = setgid(0);

1607

if(ret == -1){

1608

perror_plus("setgid");

1609

_exit(EX_NOPERM);

1610

}

1611

/* Reset supplementary groups */

1612

errno = 0;

1613

ret = setgroups(0, NULL);

1614

if(ret == -1){

1615

perror_plus("setgroups");

1616

_exit(EX_NOPERM);

1617

}

1618

ret = dup2(devnull, STDIN_FILENO);

1619

if(ret == -1){

1620

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

1621

_exit(EX_OSERR);

1622

}

1623

ret = close(devnull);

1624

if(ret == -1){

1625

perror_plus("close");

1626

_exit(EX_OSERR);

1627

}

1628

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1629

if(ret == -1){

1630

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

1631

_exit(EX_OSERR);

1632

}

1633

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

1634

if(ret == -1){

1635

perror_plus("setenv");

1636

_exit(EX_OSERR);

1637

}

1638

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

1639

if(ret == -1){

1640

perror_plus("setenv");

1641

_exit(EX_OSERR);

1642

}

1643

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

1644

if(ret == -1){

1645

perror_plus("setenv");

1646

_exit(EX_OSERR);

1647

}

1648

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

1649

if(ret == -1){

1650

perror_plus("setenv");

1651

_exit(EX_OSERR);

1652

}

1653

char *delaystring;

1654

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

1655

if(ret == -1){

1511

1656

perror_plus("asprintf");

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

}

1657

_exit(EX_OSERR);

1658

}

1659

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

1660

if(ret == -1){

1570

1661

free(delaystring);

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

perror_plus("setenv");

1663

_exit(EX_OSERR);

1664

}

1665

free(delaystring);

1666

if(connect_to != NULL){

1667

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

1668

if(ret == -1){

1669

perror_plus("setenv");

1670

_exit(EX_OSERR);

1671

}

1672

}

1673

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

1674

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

1675

perror_plus("fexecve");

1676

_exit(EXIT_FAILURE);

1677

}

1678

} else {

1679

int status;

1680

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

1681

perror_plus("waitpid");

1682

continue;

1683

}

1684

if(WIFEXITED(status)){

1685

if(WEXITSTATUS(status) != 0){

1686

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

1687

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

1688

WEXITSTATUS(status));

1689

continue;

1690

}

1691

} else if(WIFSIGNALED(status)){

1692

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

1693

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

1694

WTERMSIG(status));

1695

continue;

1582

1696

} else {

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;

1697

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

1698

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

1699

continue;

1700

}

1701

}

1702

if(debug){

1703

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

1704

direntry->d_name);

1705

}

1706

}

1707

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

1708

perror_plus("close");

1709

} else {

1710

hookdir_fd = -1;

1711

}

1712

close(devnull);

1619

1713

}

1620

1714

1715

__attribute__((nonnull, warn_unused_result))

1621

1716

error_t bring_up_interface(const char *const interface,

1622

1717

const float delay){

1623

int sd = -1;

1624

1718

error_t old_errno = errno;

1625

error_t ret_errno = 0;

1626

int ret, ret_setflags;

1719

int ret;

1627

1720

struct ifreq network;

1628

1721

unsigned int if_index = if_nametoindex(interface);

1629

1722

if(if_index == 0){

1638

1731

}

1639

1732

1640

1733

if(not interface_is_up(interface)){

1641

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

1734

error_t ret_errno = 0, ioctl_errno = 0;

1735

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

1642

1736

ret_errno = errno;

1643

1737

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

1644

1738

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

1739

errno = old_errno;

1645

1740

return ret_errno;

1646

1741

}

1647

network.ifr_flags |= IFF_UP;

1742

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

1648

1743

1649

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1650

if(sd < 0){

1744

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

1745

if(sd == -1){

1651

1746

ret_errno = errno;

1652

1747

perror_plus("socket");

1653

1748

errno = old_errno;

1654

1749

return ret_errno;

1655

1750

}

1656

1751

1657

1752

if(quit_now){

1658

close(sd);

1753

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

1754

if(ret == -1){

1755

perror_plus("close");

1756

}

1659

1757

errno = old_errno;

1660

1758

return EINTR;

1661

1759

}

1665

1763

interface);

1666

1764

}

1667

1765

1668

/* Raise priviliges */

1669

raise_privileges();

1766

/* Raise privileges */

1767

ret_errno = raise_privileges();

1768

if(ret_errno != 0){

1769

perror_plus("Failed to raise privileges");

1770

}

1670

1771

1671

1772

#ifdef __linux__

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");

1773

int ret_linux;

1774

bool restore_loglevel = false;

1775

if(ret_errno == 0){

1776

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1777

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

1778

ret_linux = klogctl(8, NULL, 5);

1779

if(ret_linux == -1){

1780

perror_plus("klogctl");

1781

} else {

1782

restore_loglevel = true;

1783

}

1679

1784

}

1680

1785

#endif /* __linux__ */

1681

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

1682

ret_errno = errno;

1786

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

1787

ioctl_errno = errno;

1683

1788

#ifdef __linux__

1684

1789

if(restore_loglevel){

1685

1790

ret_linux = klogctl(7, NULL, 0);

1689

1794

}

1690

1795

#endif /* __linux__ */

1691

1796

1692

/* Lower privileges */

1693

lower_privileges();

1797

/* If raise_privileges() succeeded above */

1798

if(ret_errno == 0){

1799

/* Lower privileges */

1800

ret_errno = lower_privileges();

1801

if(ret_errno != 0){

1802

errno = ret_errno;

1803

perror_plus("Failed to lower privileges");

1804

}

1805

}

1694

1806

1695

1807

/* Close the socket */

1696

1808

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

1699

1811

}

1700

1812

1701

1813

if(ret_setflags == -1){

1702

errno = ret_errno;

1814

errno = ioctl_errno;

1703

1815

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1704

1816

errno = old_errno;

1705

return ret_errno;

1817

return ioctl_errno;

1706

1818

}

1707

1819

} else if(debug){

1708

1820

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

1726

1838

return 0;

1727

1839

}

1728

1840

1841

__attribute__((nonnull, warn_unused_result))

1729

1842

error_t take_down_interface(const char *const interface){

1730

int sd = -1;

1731

1843

error_t old_errno = errno;

1732

error_t ret_errno = 0;

1733

int ret, ret_setflags;

1734

1844

struct ifreq network;

1735

1845

unsigned int if_index = if_nametoindex(interface);

1736

1846

if(if_index == 0){

1739

1849

return ENXIO;

1740

1850

}

1741

1851

if(interface_is_up(interface)){

1852

error_t ret_errno = 0, ioctl_errno = 0;

1742

1853

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

1743

1854

ret_errno = errno;

1744

1855

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

1745

1856

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

1857

errno = old_errno;

1746

1858

return ret_errno;

1747

1859

}

1748

1860

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

1749

1861

1750

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1751

if(sd < 0){

1862

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

1863

if(sd == -1){

1752

1864

ret_errno = errno;

1753

1865

perror_plus("socket");

1754

1866

errno = old_errno;

1760

1872

interface);

1761

1873

}

1762

1874

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();

1875

/* Raise privileges */

1876

ret_errno = raise_privileges();

1877

if(ret_errno != 0){

1878

perror_plus("Failed to raise privileges");

1879

}

1880

1881

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

1882

ioctl_errno = errno;

1883

1884

/* If raise_privileges() succeeded above */

1885

if(ret_errno == 0){

1886

/* Lower privileges */

1887

ret_errno = lower_privileges();

1888

if(ret_errno != 0){

1889

errno = ret_errno;

1890

perror_plus("Failed to lower privileges");

1891

}

1892

}

1771

1893

1772

1894

/* Close the socket */

1773

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

1895

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

1774

1896

if(ret == -1){

1775

1897

perror_plus("close");

1776

1898

}

1777

1899

1778

1900

if(ret_setflags == -1){

1779

errno = ret_errno;

1901

errno = ioctl_errno;

1780

1902

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1781

1903

errno = old_errno;

1782

return ret_errno;

1904

return ioctl_errno;

1783

1905

}

1784

1906

} else if(debug){

1785

1907

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

1793

1915

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

1794

1916

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

1795

1917

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

1796

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

1918

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

1797

1919

.interfaces = NULL, .interfaces_size = 0 };

1798

1920

AvahiSServiceBrowser *sb = NULL;

1799

1921

error_t ret_errno;

1803

1925

int exitcode = EXIT_SUCCESS;

1804

1926

char *interfaces_to_take_down = NULL;

1805

1927

size_t interfaces_to_take_down_size = 0;

1806

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

1807

bool tempdir_created = false;

1928

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

1929

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

1930

char *tempdir = NULL;

1808

1931

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1809

1932

const char *seckey = PATHDIR "/" SECKEY;

1810

1933

const char *pubkey = PATHDIR "/" PUBKEY;

1811

1934

char *interfaces_hooks = NULL;

1812

size_t interfaces_hooks_size = 0;

1813

1935

1814

1936

bool gnutls_initialized = false;

1815

1937

bool gpgme_initialized = false;

1993

2115

/* Work around Debian bug #633582:

1994

2116

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

1995

2117

1996

/* Re-raise priviliges */

1997

if(raise_privileges() == 0){

2118

/* Re-raise privileges */

2119

ret_errno = raise_privileges();

2120

if(ret_errno != 0){

2121

errno = ret_errno;

2122

perror_plus("Failed to raise privileges");

2123

} else {

1998

2124

struct stat st;

1999

2125

2000

2126

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

2040

2166

}

2041

2167

2042

2168

/* Lower privileges */

2043

lower_privileges();

2169

ret_errno = lower_privileges();

2170

if(ret_errno != 0){

2171

errno = ret_errno;

2172

perror_plus("Failed to lower privileges");

2173

}

2044

2174

}

2045

2175

}

2046

2176

2070

2200

goto end;

2071

2201

}

2072

2202

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

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

}

2203

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

2204

}

2205

run_network_hooks("start", interfaces_hooks != NULL ?

2206

interfaces_hooks : "", delay);

2081

2207

}

2082

2208

2083

2209

if(not debug){

2171

2297

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

2172

2298

direntries[i]->d_name);

2173

2299

if(ret_errno != 0){

2300

errno = ret_errno;

2174

2301

perror_plus("argz_add");

2175

2302

continue;

2176

2303

}

2210

2337

break;

2211

2338

}

2212

2339

bool interface_was_up = interface_is_up(interface);

2213

ret = bring_up_interface(interface, delay);

2340

errno = bring_up_interface(interface, delay);

2214

2341

if(not interface_was_up){

2215

if(ret != 0){

2216

errno = ret;

2342

if(errno != 0){

2217

2343

perror_plus("Failed to bring up interface");

2218

2344

} else {

2219

ret_errno = argz_add(&interfaces_to_take_down,

2220

&interfaces_to_take_down_size,

2221

interface);

2345

errno = argz_add(&interfaces_to_take_down,

2346

&interfaces_to_take_down_size,

2347

interface);

2348

if(errno != 0){

2349

perror_plus("argz_add");

2350

}

2222

2351

}

2223

2352

}

2224

2353

}

2253

2382

goto end;

2254

2383

}

2255

2384

2256

if(mkdtemp(tempdir) == NULL){

2385

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

2386

tempdir = mkdtemp(run_tempdir);

2387

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

2388

if(debug){

2389

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

2390

run_tempdir, old_tempdir);

2391

}

2392

tempdir = mkdtemp(old_tempdir);

2393

}

2394

if(tempdir == NULL){

2257

2395

perror_plus("mkdtemp");

2258

2396

goto end;

2259

2397

}

2260

tempdir_created = true;

2261

2398

2262

2399

if(quit_now){

2263

2400

goto end;

2338

2475

sleep((unsigned int)retry_interval);

2339

2476

}

2340

2477

2341

if (not quit_now){

2478

if(not quit_now){

2342

2479

exitcode = EXIT_SUCCESS;

2343

2480

}

2344

2481

2399

2536

if(debug){

2400

2537

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

2401

2538

}

2402

2539

2403

2540

ret = avahi_loop_with_timeout(simple_poll,

2404

2541

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

2405

2542

if(debug){

2446

2583

}

2447

2584

}

2448

2585

2449

/* Re-raise priviliges */

2586

/* Re-raise privileges */

2450

2587

{

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();

2588

ret_errno = raise_privileges();

2589

if(ret_errno != 0){

2590

perror_plus("Failed to raise privileges");

2591

} else {

2592

2593

/* Run network hooks */

2594

run_network_hooks("stop", interfaces_hooks != NULL ?

2595

interfaces_hooks : "", delay);

2596

2597

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

2598

{

2599

char *interface = NULL;

2600

while((interface=argz_next(interfaces_to_take_down,

2601

interfaces_to_take_down_size,

2602

interface))){

2603

ret_errno = take_down_interface(interface);

2604

if(ret_errno != 0){

2605

errno = ret_errno;

2606

perror_plus("Failed to take down interface");

2607

}

2608

}

2609

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

2610

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

2611

" down\n");

2612

}

2613

}

2614

}

2615

2616

ret_errno = lower_privileges_permanently();

2617

if(ret_errno != 0){

2618

perror_plus("Failed to lower privileges permanently");

2619

}

2476

2620

}

2477

2621

2478

2622

free(interfaces_to_take_down);

2479

2623

free(interfaces_hooks);

2480

2624

2481

2625

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

2482

if(tempdir_created){

2626

if(tempdir != NULL){

2483

2627

struct dirent **direntries = NULL;

2484

2628

struct dirent *direntry = NULL;

2485

2629

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

2486

2630

alphasort);

2487

if (numentries > 0){

2631

if(numentries > 0){

2488

2632

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

2489

2633

direntry = direntries[i];

2490

2634

char *fullname = NULL;

2502

2646

free(fullname);

2503

2647

}

2504

2648

}

2505

2649

2506

2650

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

2507

2651

free(direntries);

2508

if (numentries == -1){

2652

if(numentries == -1){

2509

2653

perror_plus("scandir");

2510

2654

}

2511

2655

ret = rmdir(tempdir);