/mandos/trunk : revision 608

9

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

10

*

11

* Everything else is

12

13

12

13

14

*

15

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

16

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

32

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

33

#ifndef _LARGEFILE_SOURCE

34

#define _LARGEFILE_SOURCE

35

#endif /* not _LARGEFILE_SOURCE */

35

#endif

36

#ifndef _FILE_OFFSET_BITS

37

#define _FILE_OFFSET_BITS 64

38

#endif /* not _FILE_OFFSET_BITS */

38

#endif

39

40

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

41

42

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

43

stdout, ferror() */

43

stdout, ferror(), remove() */

44

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

45

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

46

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

55

opendir(), DIR */

56

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

57

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

58

inet_pton(), connect(),

59

getnameinfo() */

60

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

58

inet_pton(), connect() */

59

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

61

60

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

62

61

*/

63

62

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

73

72

*/

74

73

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

75

74

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

76

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

77

unlinkat() */

78

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

75

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

76

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

79

77

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

80

78

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

81

79

argp_state, struct argp,

93

91

argz_delete(), argz_append(),

94

92

argz_stringify(), argz_add(),

95

93

argz_count() */

96

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

97

EAI_SYSTEM, gai_strerror() */

98

94

99

95

#ifdef __linux__

100

96

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

142

138

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

143

139

char *connect_to = NULL;

144

140

const char *hookdir = HOOKDIR;

145

int hookdir_fd = -1;

146

141

uid_t uid = 65534;

147

142

gid_t gid = 65534;

148

143

185

180

perror(print_text);

186

181

}

187

182

188

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

183

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

189

184

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

190

185

va_list ap;

191

186

va_start (ap, format);

192

187

193

188

TEMP_FAILURE_RETRY(fprintf(stream, "Mandos plugin %s: ",

194

189

program_invocation_short_name));

195

return (int)TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));

190

return TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));

196

191

}

197

192

198

193

/*

200

195

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

201

196

* "buffer_length" is how much is already used.

202

197

*/

203

__attribute__((nonnull, warn_unused_result))

204

198

size_t incbuffer(char **buffer, size_t buffer_length,

205

199

size_t buffer_capacity){

206

200

if(buffer_length + BUFFER_SIZE > buffer_capacity){

207

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

208

if(new_buf == NULL){

209

int old_errno = errno;

210

free(*buffer);

211

errno = old_errno;

212

*buffer = NULL;

201

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

202

if(buffer == NULL){

213

203

return 0;

214

204

}

215

*buffer = new_buf;

216

205

buffer_capacity += BUFFER_SIZE;

217

206

}

218

207

return buffer_capacity;

219

208

}

220

209

221

210

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

222

__attribute__((nonnull, warn_unused_result))

223

211

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

224

212

int af, server **current_server){

225

213

int ret;

236

224

perror_plus("strdup");

237

225

return false;

238

226

}

239

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

240

if(ret == -1){

241

perror_plus("clock_gettime");

242

return false;

243

}

244

227

/* Special case of first server */

245

228

if(*current_server == NULL){

246

229

new_server->next = new_server;

247

230

new_server->prev = new_server;

248

231

*current_server = new_server;

232

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

249

233

} else {

250

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

251

234

new_server->next = *current_server;

252

235

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

253

236

new_server->prev->next = new_server;

254

237

(*current_server)->prev = new_server;

255

238

}

239

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

240

if(ret == -1){

241

perror_plus("clock_gettime");

242

return false;

243

}

256

244

return true;

257

245

}

258

246

259

247

/*

260

248

* Initialize GPGME.

261

249

*/

262

__attribute__((nonnull, warn_unused_result))

263

static bool init_gpgme(const char * const seckey,

264

const char * const pubkey,

265

const char * const tempdir,

266

mandos_context *mc){

250

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

251

const char *tempdir, mandos_context *mc){

267

252

gpgme_error_t rc;

268

253

gpgme_engine_info_t engine_info;

269

254

270

255

/*

271

256

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

272

257

*/

273

bool import_key(const char * const filename){

258

bool import_key(const char *filename){

274

259

int ret;

275

260

int fd;

276

261

gpgme_data_t pgp_data;

357

342

* Decrypt OpenPGP data.

358

343

* Returns -1 on error

359

344

*/

360

__attribute__((nonnull, warn_unused_result))

361

345

static ssize_t pgp_packet_decrypt(const char *cryptotext,

362

346

size_t crypto_size,

363

347

char **plaintext,

483

467

return plaintext_length;

484

468

}

485

469

486

__attribute__((warn_unused_result))

487

static const char *safer_gnutls_strerror(int value){

470

static const char * safer_gnutls_strerror(int value){

488

471

const char *ret = gnutls_strerror(value);

489

472

if(ret == NULL)

490

473

ret = "(unknown)";

492

475

}

493

476

494

477

/* GnuTLS log function callback */

495

__attribute__((nonnull))

496

478

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

497

479

const char* string){

498

480

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

499

481

}

500

482

501

__attribute__((nonnull, warn_unused_result))

502

483

static int init_gnutls_global(const char *pubkeyfilename,

503

484

const char *seckeyfilename,

504

485

mandos_context *mc){

578

559

return -1;

579

560

}

580

561

581

__attribute__((nonnull, warn_unused_result))

582

562

static int init_gnutls_session(gnutls_session_t *session,

583

563

mandos_context *mc){

584

564

int ret;

641

621

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

642

622

643

623

/* Called when a Mandos server is found */

644

__attribute__((nonnull, warn_unused_result))

645

624

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

646

625

AvahiIfIndex if_index,

647

626

int af, mandos_context *mc){

648

627

int ret, tcp_sd = -1;

649

628

ssize_t sret;

650

struct sockaddr_storage to;

629

union {

630

struct sockaddr_in in;

631

struct sockaddr_in6 in6;

632

} to;

651

633

char *buffer = NULL;

652

634

char *decrypted_buffer = NULL;

653

635

size_t buffer_length = 0;

734

716

735

717

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

736

718

if(af == AF_INET6){

737

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

738

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);

739

721

} else { /* IPv4 */

740

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

741

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);

742

724

}

743

725

if(ret < 0 ){

744

726

int e = errno;

753

735

goto mandos_end;

754

736

}

755

737

if(af == AF_INET6){

756

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

757

if(IN6_IS_ADDR_LINKLOCAL

758

(&((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*/

759

742

if(if_index == AVAHI_IF_UNSPEC){

760

743

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

761

744

" incomplete without a network interface\n");

763

746

goto mandos_end;

764

747

}

765

748

/* Set the network interface number as scope */

766

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

749

to.in6.sin6_scope_id = (uint32_t)if_index;

767

750

}

768

751

} else {

769

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

752

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

753

-Wconversion and

754

-Wunreachable-code */

770

755

}

771

756

772

757

if(quit_now){

789

774

}

790

775

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

791

776

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

777

const char *pcret;

792

778

if(af == AF_INET6){

793

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

794

sizeof(struct sockaddr_in6),

795

addrstr, sizeof(addrstr), NULL, 0,

796

NI_NUMERICHOST);

779

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

780

sizeof(addrstr));

797

781

} else {

798

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

799

sizeof(struct sockaddr_in),

800

addrstr, sizeof(addrstr), NULL, 0,

801

NI_NUMERICHOST);

782

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

783

sizeof(addrstr));

802

784

}

803

if(ret == EAI_SYSTEM){

804

perror_plus("getnameinfo");

805

} else if(ret != 0) {

806

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

807

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

808

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

}

809

791

}

810

792

}

811

793

815

797

}

816

798

817

799

if(af == AF_INET6){

818

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

819

sizeof(struct sockaddr_in6));

800

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

820

801

} else {

821

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

822

sizeof(struct sockaddr_in));

802

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

823

803

}

824

804

if(ret < 0){

825

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

805

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

826

806

int e = errno;

827

807

perror_plus("connect");

828

808

errno = e;

1043

1023

return retval;

1044

1024

}

1045

1025

1046

__attribute__((nonnull))

1047

1026

static void resolve_callback(AvahiSServiceResolver *r,

1048

1027

AvahiIfIndex interface,

1049

1028

AvahiProtocol proto,

1057

1036

AVAHI_GCC_UNUSED AvahiStringList *txt,

1058

1037

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1059

1038

flags,

1060

void *mc){

1039

void* mc){

1061

1040

if(r == NULL){

1062

1041

return;

1063

1042

}

1116

1095

const char *domain,

1117

1096

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1118

1097

flags,

1119

void *mc){

1098

void* mc){

1120

1099

if(b == NULL){

1121

1100

return;

1122

1101

}

1182

1161

errno = old_errno;

1183

1162

}

1184

1163

1185

__attribute__((nonnull, warn_unused_result))

1186

1164

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

1187

1165

int ret;

1188

1166

error_t ret_errno;

1207

1185

return true;

1208

1186

}

1209

1187

1210

__attribute__((nonnull, warn_unused_result))

1211

1188

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

1212

1189

1213

1190

/* Reject the loopback device */

1255

1232

* corresponds to an acceptable network device.

1256

1233

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

1257

1234

*/

1258

__attribute__((nonnull, warn_unused_result))

1259

1235

int good_interface(const struct dirent *if_entry){

1260

1236

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

1261

1237

return 0;

1279

1255

/*

1280

1256

* This function determines if a network interface is up.

1281

1257

*/

1282

__attribute__((nonnull, warn_unused_result))

1283

1258

bool interface_is_up(const char *interface){

1284

1259

struct ifreq ifr;

1285

1260

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

1296

1271

/*

1297

1272

* This function determines if a network interface is running

1298

1273

*/

1299

__attribute__((nonnull, warn_unused_result))

1300

1274

bool interface_is_running(const char *interface){

1301

1275

struct ifreq ifr;

1302

1276

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

1310

1284

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

1311

1285

}

1312

1286

1313

__attribute__((nonnull, pure, warn_unused_result))

1314

1287

int notdotentries(const struct dirent *direntry){

1315

1288

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

1316

1289

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

1323

1296

}

1324

1297

1325

1298

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

1326

__attribute__((nonnull, warn_unused_result))

1327

1299

int runnable_hook(const struct dirent *direntry){

1328

1300

int ret;

1329

1301

size_t sret;

1337

1309

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

1338

1310

"abcdefghijklmnopqrstuvwxyz"

1339

1311

"0123456789"

1340

"_.-");

1312

"_-");

1341

1313

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

1342

1314

/* Contains non-allowed characters */

1343

1315

if(debug){

1347

1319

return 0;

1348

1320

}

1349

1321

1350

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);

1351

1330

if(ret == -1){

1352

1331

if(debug){

1353

1332

perror_plus("Could not stat hook");

1377

1356

return 1;

1378

1357

}

1379

1358

1380

__attribute__((nonnull, warn_unused_result))

1381

1359

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1382

1360

mandos_context *mc){

1383

1361

int ret;

1387

1365

1388

1366

while(true){

1389

1367

if(mc->current_server == NULL){

1390

if(debug){

1368

if (debug){

1391

1369

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

1392

1370

" No timeout!\n");

1393

1371

}

1394

1372

ret = avahi_simple_poll_iterate(s, -1);

1395

1373

} else {

1396

if(debug){

1374

if (debug){

1397

1375

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

1398

1376

" it, or wait\n");

1399

1377

}

1416

1394

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

1417

1395

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

1418

1396

1419

if(debug){

1397

if (debug){

1420

1398

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

1421

1399

block_time);

1422

1400

}

1444

1422

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

1445

1423

}

1446

1424

if(ret != 0){

1447

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

1425

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

1448

1426

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

1449

1427

}

1450

1428

}

1452

1430

}

1453

1431

1454

1432

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

1455

__attribute__((warn_unused_result))

1456

1433

error_t raise_privileges(void){

1457

1434

error_t old_errno = errno;

1458

1435

error_t ret_errno = 0;

1465

1442

}

1466

1443

1467

1444

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

1468

__attribute__((warn_unused_result))

1469

1445

error_t raise_privileges_permanently(void){

1470

1446

error_t old_errno = errno;

1471

1447

error_t ret_errno = raise_privileges();

1482

1458

}

1483

1459

1484

1460

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

1485

__attribute__((warn_unused_result))

1486

1461

error_t lower_privileges(void){

1487

1462

error_t old_errno = errno;

1488

1463

error_t ret_errno = 0;

1495

1470

}

1496

1471

1497

1472

/* Lower privileges permanently */

1498

__attribute__((warn_unused_result))

1499

1473

error_t lower_privileges_permanently(void){

1500

1474

error_t old_errno = errno;

1501

1475

error_t ret_errno = 0;

1507

1481

return ret_errno;

1508

1482

}

1509

1483

1510

#ifndef O_CLOEXEC

1511

/*

1512

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

1513

* Descriptor Flags".

1514

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

1515

*/

1516

__attribute__((warn_unused_result))

1517

static int set_cloexec_flag(int fd){

1518

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

1519

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

1520

if(ret < 0){

1521

return ret;

1522

}

1523

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

1524

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

1525

ret | FD_CLOEXEC));

1526

}

1527

#endif /* not O_CLOEXEC */

1528

1529

__attribute__((nonnull))

1530

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

1484

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

1531

1485

const float delay){

1532

1486

struct dirent **direntries;

1533

if(hookdir_fd == -1){

1534

hookdir_fd = open(hookdir, O_RDONLY |

1535

#ifdef O_CLOEXEC

1536

O_CLOEXEC

1537

#else /* not O_CLOEXEC */

1538

0

1539

#endif /* not O_CLOEXEC */

1540

);

1541

if(hookdir_fd == -1){

1542

if(errno == ENOENT){

1543

if(debug){

1544

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

1545

" found\n", hookdir);

1546

}

1547

} else {

1548

perror_plus("open");

1549

}

1550

return;

1551

}

1552

#ifndef O_CLOEXEC

1553

if(set_cloexec_flag(hookdir_fd) < 0){

1554

perror_plus("set_cloexec_flag");

1555

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

1556

perror_plus("close");

1557

} else {

1558

hookdir_fd = -1;

1559

}

1560

return;

1561

}

1562

#endif /* not O_CLOEXEC */

1563

}

1564

#ifdef __GLIBC__

1565

#if __GLIBC_PREREQ(2, 15)

1566

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

1567

runnable_hook, alphasort);

1568

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

1569

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

1570

alphasort);

1571

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

1572

#else /* not __GLIBC__ */

1573

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

1574

alphasort);

1575

#endif /* not __GLIBC__ */

1487

struct dirent *direntry;

1488

int ret;

1489

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

1490

alphasort);

1576

1491

if(numhooks == -1){

1577

perror_plus("scandir");

1578

return;

1579

}

1580

struct dirent *direntry;

1581

int ret;

1582

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

1583

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

1584

direntry = direntries[i];

1585

if(debug){

1586

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

1587

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");

1588

1499

}

1589

pid_t hook_pid = fork();

1590

if(hook_pid == 0){

1591

/* Child */

1592

/* Raise privileges */

1593

if(raise_privileges_permanently() != 0){

1594

perror_plus("Failed to raise privileges");

1595

_exit(EX_NOPERM);

1596

}

1597

/* Set group */

1598

errno = 0;

1599

ret = setgid(0);

1600

if(ret == -1){

1601

perror_plus("setgid");

1602

_exit(EX_NOPERM);

1603

}

1604

/* Reset supplementary groups */

1605

errno = 0;

1606

ret = setgroups(0, NULL);

1607

if(ret == -1){

1608

perror_plus("setgroups");

1609

_exit(EX_NOPERM);

1610

}

1611

ret = dup2(devnull, STDIN_FILENO);

1612

if(ret == -1){

1613

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

1614

_exit(EX_OSERR);

1615

}

1616

ret = close(devnull);

1617

if(ret == -1){

1618

perror_plus("close");

1619

_exit(EX_OSERR);

1620

}

1621

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1622

if(ret == -1){

1623

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

1624

_exit(EX_OSERR);

1625

}

1626

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

1627

if(ret == -1){

1628

perror_plus("setenv");

1629

_exit(EX_OSERR);

1630

}

1631

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

1632

if(ret == -1){

1633

perror_plus("setenv");

1634

_exit(EX_OSERR);

1635

}

1636

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

1637

if(ret == -1){

1638

perror_plus("setenv");

1639

_exit(EX_OSERR);

1640

}

1641

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

1642

if(ret == -1){

1643

perror_plus("setenv");

1644

_exit(EX_OSERR);

1645

}

1646

char *delaystring;

1647

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

1648

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){

1649

1507

perror_plus("asprintf");

1650

_exit(EX_OSERR);

1651

}

1652

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

1653

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

}

1654

1566

free(delaystring);

1655

perror_plus("setenv");

1656

_exit(EX_OSERR);

1657

}

1658

free(delaystring);

1659

if(connect_to != NULL){

1660

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

1661

if(ret == -1){

1662

perror_plus("setenv");

1663

_exit(EX_OSERR);

1664

}

1665

}

1666

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

1667

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

1668

perror_plus("fexecve");

1669

_exit(EXIT_FAILURE);

1670

}

1671

} else {

1672

int status;

1673

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

1674

perror_plus("waitpid");

1675

continue;

1676

}

1677

if(WIFEXITED(status)){

1678

if(WEXITSTATUS(status) != 0){

1679

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

1680

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

1681

WEXITSTATUS(status));

1682

continue;

1683

}

1684

} else if(WIFSIGNALED(status)){

1685

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

1686

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

1687

WTERMSIG(status));

1688

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

}

1689

1578

} else {

1690

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

1691

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

1692

continue;

1693

}

1694

}

1695

if(debug){

1696

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

1697

direntry->d_name);

1698

}

1699

}

1700

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

1701

perror_plus("close");

1702

} else {

1703

hookdir_fd = -1;

1704

}

1705

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;

1706

1615

}

1707

1616

1708

__attribute__((nonnull, warn_unused_result))

1709

1617

error_t bring_up_interface(const char *const interface,

1710

1618

const float delay){

1619

int sd = -1;

1711

1620

error_t old_errno = errno;

1712

int ret;

1621

error_t ret_errno = 0;

1622

int ret, ret_setflags;

1713

1623

struct ifreq network;

1714

1624

unsigned int if_index = if_nametoindex(interface);

1715

1625

if(if_index == 0){

1724

1634

}

1725

1635

1726

1636

if(not interface_is_up(interface)){

1727

error_t ret_errno = 0, ioctl_errno = 0;

1728

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

1637

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

1729

1638

ret_errno = errno;

1730

1639

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

1731

1640

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

1732

errno = old_errno;

1733

1641

return ret_errno;

1734

1642

}

1735

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

1643

network.ifr_flags |= IFF_UP;

1736

1644

1737

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

1738

if(sd == -1){

1645

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1646

if(sd < 0){

1739

1647

ret_errno = errno;

1740

1648

perror_plus("socket");

1741

1649

errno = old_errno;

1742

1650

return ret_errno;

1743

1651

}

1744

1652

1745

1653

if(quit_now){

1746

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

1747

if(ret == -1){

1748

perror_plus("close");

1749

}

1654

close(sd);

1750

1655

errno = old_errno;

1751

1656

return EINTR;

1752

1657

}

1756

1661

interface);

1757

1662

}

1758

1663

1759

/* Raise privileges */

1760

ret_errno = raise_privileges();

1761

if(ret_errno != 0){

1762

perror_plus("Failed to raise privileges");

1763

}

1664

/* Raise priviliges */

1665

raise_privileges();

1764

1666

1765

1667

#ifdef __linux__

1766

int ret_linux;

1767

bool restore_loglevel = false;

1768

if(ret_errno == 0){

1769

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1770

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

1771

ret_linux = klogctl(8, NULL, 5);

1772

if(ret_linux == -1){

1773

perror_plus("klogctl");

1774

} else {

1775

restore_loglevel = true;

1776

}

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");

1777

1675

}

1778

1676

#endif /* __linux__ */

1779

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

1780

ioctl_errno = errno;

1677

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

1678

ret_errno = errno;

1781

1679

#ifdef __linux__

1782

1680

if(restore_loglevel){

1783

1681

ret_linux = klogctl(7, NULL, 0);

1787

1685

}

1788

1686

#endif /* __linux__ */

1789

1687

1790

/* If raise_privileges() succeeded above */

1791

if(ret_errno == 0){

1792

/* Lower privileges */

1793

ret_errno = lower_privileges();

1794

if(ret_errno != 0){

1795

errno = ret_errno;

1796

perror_plus("Failed to lower privileges");

1797

}

1798

}

1688

/* Lower privileges */

1689

lower_privileges();

1799

1690

1800

1691

/* Close the socket */

1801

1692

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

1804

1695

}

1805

1696

1806

1697

if(ret_setflags == -1){

1807

errno = ioctl_errno;

1698

errno = ret_errno;

1808

1699

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1809

1700

errno = old_errno;

1810

return ioctl_errno;

1701

return ret_errno;

1811

1702

}

1812

1703

} else if(debug){

1813

1704

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

1831

1722

return 0;

1832

1723

}

1833

1724

1834

__attribute__((nonnull, warn_unused_result))

1835

1725

error_t take_down_interface(const char *const interface){

1726

int sd = -1;

1836

1727

error_t old_errno = errno;

1728

error_t ret_errno = 0;

1729

int ret, ret_setflags;

1837

1730

struct ifreq network;

1838

1731

unsigned int if_index = if_nametoindex(interface);

1839

1732

if(if_index == 0){

1842

1735

return ENXIO;

1843

1736

}

1844

1737

if(interface_is_up(interface)){

1845

error_t ret_errno = 0, ioctl_errno = 0;

1846

1738

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

1847

1739

ret_errno = errno;

1848

1740

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

1849

1741

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

1850

errno = old_errno;

1851

1742

return ret_errno;

1852

1743

}

1853

1744

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

1854

1745

1855

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

1856

if(sd == -1){

1746

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1747

if(sd < 0){

1857

1748

ret_errno = errno;

1858

1749

perror_plus("socket");

1859

1750

errno = old_errno;

1865

1756

interface);

1866

1757

}

1867

1758

1868

/* Raise privileges */

1869

ret_errno = raise_privileges();

1870

if(ret_errno != 0){

1871

perror_plus("Failed to raise privileges");

1872

}

1873

1874

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

1875

ioctl_errno = errno;

1876

1877

/* If raise_privileges() succeeded above */

1878

if(ret_errno == 0){

1879

/* Lower privileges */

1880

ret_errno = lower_privileges();

1881

if(ret_errno != 0){

1882

errno = ret_errno;

1883

perror_plus("Failed to lower privileges");

1884

}

1885

}

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();

1886

1767

1887

1768

/* Close the socket */

1888

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

1769

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

1889

1770

if(ret == -1){

1890

1771

perror_plus("close");

1891

1772

}

1892

1773

1893

1774

if(ret_setflags == -1){

1894

errno = ioctl_errno;

1775

errno = ret_errno;

1895

1776

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1896

1777

errno = old_errno;

1897

return ioctl_errno;

1778

return ret_errno;

1898

1779

}

1899

1780

} else if(debug){

1900

1781

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

1908

1789

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

1909

1790

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

1910

1791

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

1911

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

1792

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

1912

1793

.interfaces = NULL, .interfaces_size = 0 };

1913

1794

AvahiSServiceBrowser *sb = NULL;

1914

1795

error_t ret_errno;

1918

1799

int exitcode = EXIT_SUCCESS;

1919

1800

char *interfaces_to_take_down = NULL;

1920

1801

size_t interfaces_to_take_down_size = 0;

1921

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

1922

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

1923

char *tempdir = NULL;

1802

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

1803

bool tempdir_created = false;

1924

1804

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1925

1805

const char *seckey = PATHDIR "/" SECKEY;

1926

1806

const char *pubkey = PATHDIR "/" PUBKEY;

1927

1807

char *interfaces_hooks = NULL;

1808

size_t interfaces_hooks_size = 0;

1928

1809

1929

1810

bool gnutls_initialized = false;

1930

1811

bool gpgme_initialized = false;

2108

1989

/* Work around Debian bug #633582:

2109

1990

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

2110

1991

2111

/* Re-raise privileges */

2112

ret_errno = raise_privileges();

2113

if(ret_errno != 0){

2114

errno = ret_errno;

2115

perror_plus("Failed to raise privileges");

2116

} else {

1992

/* Re-raise priviliges */

1993

if(raise_privileges() == 0){

2117

1994

struct stat st;

2118

1995

2119

1996

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

2159

2036

}

2160

2037

2161

2038

/* Lower privileges */

2162

ret_errno = lower_privileges();

2163

if(ret_errno != 0){

2164

errno = ret_errno;

2165

perror_plus("Failed to lower privileges");

2166

}

2039

lower_privileges();

2167

2040

}

2168

2041

}

2169

2042

2193

2066

goto end;

2194

2067

}

2195

2068

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

2196

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

2197

}

2198

run_network_hooks("start", interfaces_hooks != NULL ?

2199

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

}

2200

2077

}

2201

2078

2202

2079

if(not debug){

2290

2167

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

2291

2168

direntries[i]->d_name);

2292

2169

if(ret_errno != 0){

2293

errno = ret_errno;

2294

2170

perror_plus("argz_add");

2295

2171

continue;

2296

2172

}

2330

2206

break;

2331

2207

}

2332

2208

bool interface_was_up = interface_is_up(interface);

2333

errno = bring_up_interface(interface, delay);

2209

ret = bring_up_interface(interface, delay);

2334

2210

if(not interface_was_up){

2335

if(errno != 0){

2211

if(ret != 0){

2212

errno = ret;

2336

2213

perror_plus("Failed to bring up interface");

2337

2214

} else {

2338

errno = argz_add(&interfaces_to_take_down,

2339

&interfaces_to_take_down_size,

2340

interface);

2341

if(errno != 0){

2342

perror_plus("argz_add");

2343

}

2215

ret_errno = argz_add(&interfaces_to_take_down,

2216

&interfaces_to_take_down_size,

2217

interface);

2344

2218

}

2345

2219

}

2346

2220

}

2375

2249

goto end;

2376

2250

}

2377

2251

2378

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

2379

tempdir = mkdtemp(run_tempdir);

2380

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

2381

if(debug){

2382

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

2383

run_tempdir, old_tempdir);

2384

}

2385

tempdir = mkdtemp(old_tempdir);

2386

}

2387

if(tempdir == NULL){

2252

if(mkdtemp(tempdir) == NULL){

2388

2253

perror_plus("mkdtemp");

2389

2254

goto end;

2390

2255

}

2256

tempdir_created = true;

2391

2257

2392

2258

if(quit_now){

2393

2259

goto end;

2465

2331

fprintf_plus(stderr, "Retrying in %d seconds\n",

2466

2332

(int)retry_interval);

2467

2333

}

2468

sleep((unsigned int)retry_interval);

2334

sleep((int)retry_interval);

2469

2335

}

2470

2336

2471

if(not quit_now){

2337

if (not quit_now){

2472

2338

exitcode = EXIT_SUCCESS;

2473

2339

}

2474

2340

2529

2395

if(debug){

2530

2396

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

2531

2397

}

2532

2398

2533

2399

ret = avahi_loop_with_timeout(simple_poll,

2534

2400

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

2535

2401

if(debug){

2576

2442

}

2577

2443

}

2578

2444

2579

/* Re-raise privileges */

2445

/* Re-raise priviliges */

2580

2446

{

2581

ret_errno = raise_privileges();

2582

if(ret_errno != 0){

2583

perror_plus("Failed to raise privileges");

2584

} else {

2585

2586

/* Run network hooks */

2587

run_network_hooks("stop", interfaces_hooks != NULL ?

2588

interfaces_hooks : "", delay);

2589

2590

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

2591

{

2592

char *interface = NULL;

2593

while((interface=argz_next(interfaces_to_take_down,

2594

interfaces_to_take_down_size,

2595

interface))){

2596

ret_errno = take_down_interface(interface);

2597

if(ret_errno != 0){

2598

errno = ret_errno;

2599

perror_plus("Failed to take down interface");

2600

}

2601

}

2602

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

2603

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

2604

" down\n");

2605

}

2606

}

2607

}

2608

2609

ret_errno = lower_privileges_permanently();

2610

if(ret_errno != 0){

2611

perror_plus("Failed to lower privileges permanently");

2612

}

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();

2613

2472

}

2614

2473

2615

2474

free(interfaces_to_take_down);

2616

2475

free(interfaces_hooks);

2617

2476

2618

2477

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

2619

if(tempdir != NULL){

2478

if(tempdir_created){

2620

2479

struct dirent **direntries = NULL;

2621

int tempdir_fd = (int)TEMP_FAILURE_RETRY(open(tempdir, O_RDONLY));

2622

if(tempdir_fd == -1){

2623

perror_plus("open");

2624

} else {

2625

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

2626

alphasort);

2627

if(numentries > 0){

2628

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

2629

ret = unlinkat(tempdir_fd, direntries[i]->d_name, 0);

2630

if(ret == -1){

2631

fprintf_plus(stderr, "unlinkat(open(\"%s\", O_RDONLY),"

2632

" \"%s\", 0): %s\n", tempdir,

2633

direntries[i]->d_name, strerror(errno));

2634

}

2635

}

2636

2637

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

2638

free(direntries);

2639

if(numentries == -1){

2640

perror_plus("scandir");

2641

}

2642

ret = rmdir(tempdir);

2643

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

2644

perror_plus("rmdir");

2645

}

2480

struct dirent *direntry = NULL;

2481

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

2482

alphasort);

2483

if (numentries > 0){

2484

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

2485

direntry = direntries[i];

2486

char *fullname = NULL;

2487

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

2488

direntry->d_name);

2489

if(ret < 0){

2490

perror_plus("asprintf");

2491

continue;

2492

}

2493

ret = remove(fullname);

2494

if(ret == -1){

2495

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

2496

strerror(errno));

2497

}

2498

free(fullname);

2646

2499

}

2647

TEMP_FAILURE_RETRY(close(tempdir_fd));

2500

}

2501

2502

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

2503

free(direntries);

2504

if (numentries == -1){

2505

perror_plus("scandir");

2506

}

2507

ret = rmdir(tempdir);

2508

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

2509

perror_plus("rmdir");

2648

2510

}

2649

2511

}

2650

2512