/mandos/trunk : revision 697

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

42

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

43

stdout, ferror(), remove() */

43

stdout, ferror() */

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

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

58

inet_pton(), connect(),

59

getnameinfo() */

60

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

60

61

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

61

62

*/

62

63

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

72

73

*/

73

74

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

74

75

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

75

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

76

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

76

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

77

unlinkat() */

78

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

77

79

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

78

80

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

79

81

argp_state, struct argp,

91

93

argz_delete(), argz_append(),

92

94

argz_stringify(), argz_add(),

93

95

argz_count() */

96

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

97

EAI_SYSTEM, gai_strerror() */

94

98

95

99

#ifdef __linux__

96

100

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

138

142

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

139

143

char *connect_to = NULL;

140

144

const char *hookdir = HOOKDIR;

145

int hookdir_fd = -1;

141

146

uid_t uid = 65534;

142

147

gid_t gid = 65534;

143

148

180

185

perror(print_text);

181

186

}

182

187

183

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

188

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

184

189

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

185

190

va_list ap;

186

191

va_start (ap, format);

187

192

188

193

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

189

194

program_invocation_short_name));

190

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

195

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

191

196

}

192

197

193

198

/*

195

200

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

196

201

* "buffer_length" is how much is already used.

197

202

*/

203

__attribute__((nonnull, warn_unused_result))

198

204

size_t incbuffer(char **buffer, size_t buffer_length,

199

205

size_t buffer_capacity){

200

206

if(buffer_length + BUFFER_SIZE > buffer_capacity){

201

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

202

if(buffer == NULL){

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;

203

213

return 0;

204

214

}

215

*buffer = new_buf;

205

216

buffer_capacity += BUFFER_SIZE;

206

217

}

207

218

return buffer_capacity;

208

219

}

209

220

210

221

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

222

__attribute__((nonnull, warn_unused_result))

211

223

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

212

224

int af, server **current_server){

213

225

int ret;

224

236

perror_plus("strdup");

225

237

return false;

226

238

}

239

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

240

if(ret == -1){

241

perror_plus("clock_gettime");

242

return false;

243

}

227

244

/* Special case of first server */

228

245

if(*current_server == NULL){

229

246

new_server->next = new_server;

230

247

new_server->prev = new_server;

231

248

*current_server = new_server;

232

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

233

249

} else {

250

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

234

251

new_server->next = *current_server;

235

252

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

236

253

new_server->prev->next = new_server;

237

254

(*current_server)->prev = new_server;

238

255

}

239

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

240

if(ret == -1){

241

perror_plus("clock_gettime");

242

return false;

243

}

244

256

return true;

245

257

}

246

258

247

259

/*

248

260

* Initialize GPGME.

249

261

*/

250

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

251

const char *tempdir, mandos_context *mc){

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){

252

267

gpgme_error_t rc;

253

268

gpgme_engine_info_t engine_info;

254

269

255

270

/*

256

271

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

257

272

*/

258

bool import_key(const char *filename){

273

bool import_key(const char * const filename){

259

274

int ret;

260

275

int fd;

261

276

gpgme_data_t pgp_data;

342

357

* Decrypt OpenPGP data.

343

358

* Returns -1 on error

344

359

*/

360

__attribute__((nonnull, warn_unused_result))

345

361

static ssize_t pgp_packet_decrypt(const char *cryptotext,

346

362

size_t crypto_size,

347

363

char **plaintext,

467

483

return plaintext_length;

468

484

}

469

485

470

static const char * safer_gnutls_strerror(int value){

486

__attribute__((warn_unused_result))

487

static const char *safer_gnutls_strerror(int value){

471

488

const char *ret = gnutls_strerror(value);

472

489

if(ret == NULL)

473

490

ret = "(unknown)";

475

492

}

476

493

477

494

/* GnuTLS log function callback */

495

__attribute__((nonnull))

478

496

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

479

497

const char* string){

480

498

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

481

499

}

482

500

501

__attribute__((nonnull, warn_unused_result))

483

502

static int init_gnutls_global(const char *pubkeyfilename,

484

503

const char *seckeyfilename,

485

504

mandos_context *mc){

559

578

return -1;

560

579

}

561

580

581

__attribute__((nonnull, warn_unused_result))

562

582

static int init_gnutls_session(gnutls_session_t *session,

563

583

mandos_context *mc){

564

584

int ret;

621

641

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

622

642

623

643

/* Called when a Mandos server is found */

644

__attribute__((nonnull, warn_unused_result))

624

645

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

625

646

AvahiIfIndex if_index,

626

647

int af, mandos_context *mc){

627

648

int ret, tcp_sd = -1;

628

649

ssize_t sret;

629

union {

630

struct sockaddr_in in;

631

struct sockaddr_in6 in6;

632

} to;

650

struct sockaddr_storage to;

633

651

char *buffer = NULL;

634

652

char *decrypted_buffer = NULL;

635

653

size_t buffer_length = 0;

716

734

717

735

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

718

736

if(af == AF_INET6){

719

to.in6.sin6_family = (sa_family_t)af;

720

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

737

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

738

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

721

739

} else { /* IPv4 */

722

to.in.sin_family = (sa_family_t)af;

723

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

740

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

741

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

724

742

}

725

743

if(ret < 0 ){

726

744

int e = errno;

735

753

goto mandos_end;

736

754

}

737

755

if(af == AF_INET6){

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*/

756

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

757

if(IN6_IS_ADDR_LINKLOCAL

758

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

742

759

if(if_index == AVAHI_IF_UNSPEC){

743

760

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

744

761

" incomplete without a network interface\n");

746

763

goto mandos_end;

747

764

}

748

765

/* Set the network interface number as scope */

749

to.in6.sin6_scope_id = (uint32_t)if_index;

766

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

750

767

}

751

768

} else {

752

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

753

-Wconversion and

754

-Wunreachable-code */

769

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

755

770

}

756

771

757

772

if(quit_now){

774

789

}

775

790

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

776

791

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

777

const char *pcret;

778

792

if(af == AF_INET6){

779

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

780

sizeof(addrstr));

793

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

794

sizeof(struct sockaddr_in6),

795

addrstr, sizeof(addrstr), NULL, 0,

796

NI_NUMERICHOST);

781

797

} else {

782

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

783

sizeof(addrstr));

798

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

799

sizeof(struct sockaddr_in),

800

addrstr, sizeof(addrstr), NULL, 0,

801

NI_NUMERICHOST);

784

802

}

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

}

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);

791

809

}

792

810

}

793

811

797

815

}

798

816

799

817

if(af == AF_INET6){

800

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

818

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

819

sizeof(struct sockaddr_in6));

801

820

} else {

802

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

821

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

822

sizeof(struct sockaddr_in));

803

823

}

804

824

if(ret < 0){

805

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

825

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

806

826

int e = errno;

807

827

perror_plus("connect");

808

828

errno = e;

1023

1043

return retval;

1024

1044

}

1025

1045

1046

__attribute__((nonnull))

1026

1047

static void resolve_callback(AvahiSServiceResolver *r,

1027

1048

AvahiIfIndex interface,

1028

1049

AvahiProtocol proto,

1036

1057

AVAHI_GCC_UNUSED AvahiStringList *txt,

1037

1058

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1038

1059

flags,

1039

void* mc){

1060

void *mc){

1040

1061

if(r == NULL){

1041

1062

return;

1042

1063

}

1095

1116

const char *domain,

1096

1117

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1097

1118

flags,

1098

void* mc){

1119

void *mc){

1099

1120

if(b == NULL){

1100

1121

return;

1101

1122

}

1161

1182

errno = old_errno;

1162

1183

}

1163

1184

1185

__attribute__((nonnull, warn_unused_result))

1164

1186

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

1165

1187

int ret;

1166

1188

error_t ret_errno;

1185

1207

return true;

1186

1208

}

1187

1209

1210

__attribute__((nonnull, warn_unused_result))

1188

1211

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

1189

1212

1190

1213

/* Reject the loopback device */

1232

1255

* corresponds to an acceptable network device.

1233

1256

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

1234

1257

*/

1258

__attribute__((nonnull, warn_unused_result))

1235

1259

int good_interface(const struct dirent *if_entry){

1236

1260

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

1237

1261

return 0;

1255

1279

/*

1256

1280

* This function determines if a network interface is up.

1257

1281

*/

1282

__attribute__((nonnull, warn_unused_result))

1258

1283

bool interface_is_up(const char *interface){

1259

1284

struct ifreq ifr;

1260

1285

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

1271

1296

/*

1272

1297

* This function determines if a network interface is running

1273

1298

*/

1299

__attribute__((nonnull, warn_unused_result))

1274

1300

bool interface_is_running(const char *interface){

1275

1301

struct ifreq ifr;

1276

1302

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

1284

1310

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

1285

1311

}

1286

1312

1313

__attribute__((nonnull, pure, warn_unused_result))

1287

1314

int notdotentries(const struct dirent *direntry){

1288

1315

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

1289

1316

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

1296

1323

}

1297

1324

1298

1325

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

1326

__attribute__((nonnull, warn_unused_result))

1299

1327

int runnable_hook(const struct dirent *direntry){

1300

1328

int ret;

1301

1329

size_t sret;

1309

1337

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

1310

1338

"abcdefghijklmnopqrstuvwxyz"

1311

1339

"0123456789"

1312

"_-");

1340

"_.-");

1313

1341

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

1314

1342

/* Contains non-allowed characters */

1315

1343

if(debug){

1319

1347

return 0;

1320

1348

}

1321

1349

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

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

1330

1351

if(ret == -1){

1331

1352

if(debug){

1332

1353

perror_plus("Could not stat hook");

1356

1377

return 1;

1357

1378

}

1358

1379

1380

__attribute__((nonnull, warn_unused_result))

1359

1381

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1360

1382

mandos_context *mc){

1361

1383

int ret;

1365

1387

1366

1388

while(true){

1367

1389

if(mc->current_server == NULL){

1368

if (debug){

1390

if(debug){

1369

1391

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

1370

1392

" No timeout!\n");

1371

1393

}

1372

1394

ret = avahi_simple_poll_iterate(s, -1);

1373

1395

} else {

1374

if (debug){

1396

if(debug){

1375

1397

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

1376

1398

" it, or wait\n");

1377

1399

}

1394

1416

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

1395

1417

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

1396

1418

1397

if (debug){

1419

if(debug){

1398

1420

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

1399

1421

block_time);

1400

1422

}

1422

1444

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

1423

1445

}

1424

1446

if(ret != 0){

1425

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

1447

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

1426

1448

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

1427

1449

}

1428

1450

}

1430

1452

}

1431

1453

1432

1454

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

1455

__attribute__((warn_unused_result))

1433

1456

error_t raise_privileges(void){

1434

1457

error_t old_errno = errno;

1435

1458

error_t ret_errno = 0;

1442

1465

}

1443

1466

1444

1467

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

1468

__attribute__((warn_unused_result))

1445

1469

error_t raise_privileges_permanently(void){

1446

1470

error_t old_errno = errno;

1447

1471

error_t ret_errno = raise_privileges();

1458

1482

}

1459

1483

1460

1484

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

1485

__attribute__((warn_unused_result))

1461

1486

error_t lower_privileges(void){

1462

1487

error_t old_errno = errno;

1463

1488

error_t ret_errno = 0;

1470

1495

}

1471

1496

1472

1497

/* Lower privileges permanently */

1498

__attribute__((warn_unused_result))

1473

1499

error_t lower_privileges_permanently(void){

1474

1500

error_t old_errno = errno;

1475

1501

error_t ret_errno = 0;

1481

1507

return ret_errno;

1482

1508

}

1483

1509

1484

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

1510

__attribute__((nonnull))

1511

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

1485

1512

const float delay){

1486

1513

struct dirent **direntries;

1514

if(hookdir_fd == -1){

1515

hookdir_fd = open(hookdir, O_RDONLY);

1516

if(hookdir_fd == -1){

1517

if(errno == ENOENT){

1518

if(debug){

1519

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

1520

" found\n", hookdir);

1521

}

1522

} else {

1523

perror_plus("open");

1524

}

1525

return;

1526

}

1527

}

1528

#ifdef __GLIBC__

1529

#if __GLIBC_PREREQ(2, 15)

1530

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

1531

runnable_hook, alphasort);

1532

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

1533

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

1534

alphasort);

1535

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

1536

#else /* not __GLIBC__ */

1537

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

1538

alphasort);

1539

#endif /* not __GLIBC__ */

1540

if(numhooks == -1){

1541

perror_plus("scandir");

1542

return;

1543

}

1487

1544

struct dirent *direntry;

1488

1545

int ret;

1489

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

1490

alphasort);

1491

if(numhooks == -1){

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");

1546

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

1547

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

1548

direntry = direntries[i];

1549

if(debug){

1550

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

1551

direntry->d_name);

1499

1552

}

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){

1553

pid_t hook_pid = fork();

1554

if(hook_pid == 0){

1555

/* Child */

1556

/* Raise privileges */

1557

if(raise_privileges_permanently() != 0){

1558

perror_plus("Failed to raise privileges");

1559

_exit(EX_NOPERM);

1560

}

1561

/* Set group */

1562

errno = 0;

1563

ret = setgid(0);

1564

if(ret == -1){

1565

perror_plus("setgid");

1566

_exit(EX_NOPERM);

1567

}

1568

/* Reset supplementary groups */

1569

errno = 0;

1570

ret = setgroups(0, NULL);

1571

if(ret == -1){

1572

perror_plus("setgroups");

1573

_exit(EX_NOPERM);

1574

}

1575

ret = dup2(devnull, STDIN_FILENO);

1576

if(ret == -1){

1577

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

1578

_exit(EX_OSERR);

1579

}

1580

ret = close(devnull);

1581

if(ret == -1){

1582

perror_plus("close");

1583

_exit(EX_OSERR);

1584

}

1585

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1586

if(ret == -1){

1587

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

1588

_exit(EX_OSERR);

1589

}

1590

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

1591

if(ret == -1){

1592

perror_plus("setenv");

1593

_exit(EX_OSERR);

1594

}

1595

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

1596

if(ret == -1){

1597

perror_plus("setenv");

1598

_exit(EX_OSERR);

1599

}

1600

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

1601

if(ret == -1){

1602

perror_plus("setenv");

1603

_exit(EX_OSERR);

1604

}

1605

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

1606

if(ret == -1){

1607

perror_plus("setenv");

1608

_exit(EX_OSERR);

1609

}

1610

char *delaystring;

1611

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

1612

if(ret == -1){

1507

1613

perror_plus("asprintf");

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

}

1614

_exit(EX_OSERR);

1615

}

1616

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

1617

if(ret == -1){

1566

1618

free(delaystring);

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

}

1619

perror_plus("setenv");

1620

_exit(EX_OSERR);

1621

}

1622

free(delaystring);

1623

if(connect_to != NULL){

1624

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

1625

if(ret == -1){

1626

perror_plus("setenv");

1627

_exit(EX_OSERR);

1628

}

1629

}

1630

int hook_fd = openat(hookdir_fd, direntry->d_name, O_RDONLY);

1631

if(hook_fd == -1){

1632

perror_plus("openat");

1633

_exit(EXIT_FAILURE);

1634

}

1635

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

1636

perror_plus("close");

1637

_exit(EXIT_FAILURE);

1638

}

1639

if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },

1640

environ) == -1){

1641

perror_plus("fexecve");

1642

_exit(EXIT_FAILURE);

1643

}

1644

} else {

1645

int status;

1646

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

1647

perror_plus("waitpid");

1648

continue;

1649

}

1650

if(WIFEXITED(status)){

1651

if(WEXITSTATUS(status) != 0){

1652

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

1653

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

1654

WEXITSTATUS(status));

1655

continue;

1656

}

1657

} else if(WIFSIGNALED(status)){

1658

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

1659

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

1660

WTERMSIG(status));

1661

continue;

1578

1662

} else {

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;

1663

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

1664

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

1665

continue;

1666

}

1667

}

1668

if(debug){

1669

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

1670

direntry->d_name);

1671

}

1672

}

1673

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

1674

perror_plus("close");

1675

} else {

1676

hookdir_fd = -1;

1677

}

1678

close(devnull);

1615

1679

}

1616

1680

1681

__attribute__((nonnull, warn_unused_result))

1617

1682

error_t bring_up_interface(const char *const interface,

1618

1683

const float delay){

1619

int sd = -1;

1620

1684

error_t old_errno = errno;

1621

error_t ret_errno = 0;

1622

int ret, ret_setflags;

1685

int ret;

1623

1686

struct ifreq network;

1624

1687

unsigned int if_index = if_nametoindex(interface);

1625

1688

if(if_index == 0){

1634

1697

}

1635

1698

1636

1699

if(not interface_is_up(interface)){

1637

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

1700

error_t ret_errno = 0, ioctl_errno = 0;

1701

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

1638

1702

ret_errno = errno;

1639

1703

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

1640

1704

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

1705

errno = old_errno;

1641

1706

return ret_errno;

1642

1707

}

1643

network.ifr_flags |= IFF_UP;

1708

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

1644

1709

1645

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1646

if(sd < 0){

1710

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

1711

if(sd == -1){

1647

1712

ret_errno = errno;

1648

1713

perror_plus("socket");

1649

1714

errno = old_errno;

1650

1715

return ret_errno;

1651

1716

}

1652

1717

1653

1718

if(quit_now){

1654

close(sd);

1719

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

1720

if(ret == -1){

1721

perror_plus("close");

1722

}

1655

1723

errno = old_errno;

1656

1724

return EINTR;

1657

1725

}

1661

1729

interface);

1662

1730

}

1663

1731

1664

/* Raise priviliges */

1665

raise_privileges();

1732

/* Raise privileges */

1733

ret_errno = raise_privileges();

1734

if(ret_errno != 0){

1735

perror_plus("Failed to raise privileges");

1736

}

1666

1737

1667

1738

#ifdef __linux__

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");

1739

int ret_linux;

1740

bool restore_loglevel = false;

1741

if(ret_errno == 0){

1742

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1743

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

1744

ret_linux = klogctl(8, NULL, 5);

1745

if(ret_linux == -1){

1746

perror_plus("klogctl");

1747

} else {

1748

restore_loglevel = true;

1749

}

1675

1750

}

1676

1751

#endif /* __linux__ */

1677

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

1678

ret_errno = errno;

1752

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

1753

ioctl_errno = errno;

1679

1754

#ifdef __linux__

1680

1755

if(restore_loglevel){

1681

1756

ret_linux = klogctl(7, NULL, 0);

1685

1760

}

1686

1761

#endif /* __linux__ */

1687

1762

1688

/* Lower privileges */

1689

lower_privileges();

1763

/* If raise_privileges() succeeded above */

1764

if(ret_errno == 0){

1765

/* Lower privileges */

1766

ret_errno = lower_privileges();

1767

if(ret_errno != 0){

1768

errno = ret_errno;

1769

perror_plus("Failed to lower privileges");

1770

}

1771

}

1690

1772

1691

1773

/* Close the socket */

1692

1774

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

1695

1777

}

1696

1778

1697

1779

if(ret_setflags == -1){

1698

errno = ret_errno;

1780

errno = ioctl_errno;

1699

1781

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1700

1782

errno = old_errno;

1701

return ret_errno;

1783

return ioctl_errno;

1702

1784

}

1703

1785

} else if(debug){

1704

1786

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

1722

1804

return 0;

1723

1805

}

1724

1806

1807

__attribute__((nonnull, warn_unused_result))

1725

1808

error_t take_down_interface(const char *const interface){

1726

int sd = -1;

1727

1809

error_t old_errno = errno;

1728

error_t ret_errno = 0;

1729

int ret, ret_setflags;

1730

1810

struct ifreq network;

1731

1811

unsigned int if_index = if_nametoindex(interface);

1732

1812

if(if_index == 0){

1735

1815

return ENXIO;

1736

1816

}

1737

1817

if(interface_is_up(interface)){

1818

error_t ret_errno = 0, ioctl_errno = 0;

1738

1819

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

1739

1820

ret_errno = errno;

1740

1821

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

1741

1822

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

1823

errno = old_errno;

1742

1824

return ret_errno;

1743

1825

}

1744

1826

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

1745

1827

1746

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1747

if(sd < 0){

1828

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

1829

if(sd == -1){

1748

1830

ret_errno = errno;

1749

1831

perror_plus("socket");

1750

1832

errno = old_errno;

1756

1838

interface);

1757

1839

}

1758

1840

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();

1841

/* Raise privileges */

1842

ret_errno = raise_privileges();

1843

if(ret_errno != 0){

1844

perror_plus("Failed to raise privileges");

1845

}

1846

1847

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

1848

ioctl_errno = errno;

1849

1850

/* If raise_privileges() succeeded above */

1851

if(ret_errno == 0){

1852

/* Lower privileges */

1853

ret_errno = lower_privileges();

1854

if(ret_errno != 0){

1855

errno = ret_errno;

1856

perror_plus("Failed to lower privileges");

1857

}

1858

}

1767

1859

1768

1860

/* Close the socket */

1769

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

1861

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

1770

1862

if(ret == -1){

1771

1863

perror_plus("close");

1772

1864

}

1773

1865

1774

1866

if(ret_setflags == -1){

1775

errno = ret_errno;

1867

errno = ioctl_errno;

1776

1868

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1777

1869

errno = old_errno;

1778

return ret_errno;

1870

return ioctl_errno;

1779

1871

}

1780

1872

} else if(debug){

1781

1873

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

1789

1881

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

1790

1882

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

1791

1883

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

1792

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

1884

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

1793

1885

.interfaces = NULL, .interfaces_size = 0 };

1794

1886

AvahiSServiceBrowser *sb = NULL;

1795

1887

error_t ret_errno;

1799

1891

int exitcode = EXIT_SUCCESS;

1800

1892

char *interfaces_to_take_down = NULL;

1801

1893

size_t interfaces_to_take_down_size = 0;

1802

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

1803

bool tempdir_created = false;

1894

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

1895

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

1896

char *tempdir = NULL;

1804

1897

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1805

1898

const char *seckey = PATHDIR "/" SECKEY;

1806

1899

const char *pubkey = PATHDIR "/" PUBKEY;

1807

1900

char *interfaces_hooks = NULL;

1808

size_t interfaces_hooks_size = 0;

1809

1901

1810

1902

bool gnutls_initialized = false;

1811

1903

bool gpgme_initialized = false;

1989

2081

/* Work around Debian bug #633582:

1990

2082

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

1991

2083

1992

/* Re-raise priviliges */

1993

if(raise_privileges() == 0){

2084

/* Re-raise privileges */

2085

ret_errno = raise_privileges();

2086

if(ret_errno != 0){

2087

errno = ret_errno;

2088

perror_plus("Failed to raise privileges");

2089

} else {

1994

2090

struct stat st;

1995

2091

1996

2092

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

2036

2132

}

2037

2133

2038

2134

/* Lower privileges */

2039

lower_privileges();

2135

ret_errno = lower_privileges();

2136

if(ret_errno != 0){

2137

errno = ret_errno;

2138

perror_plus("Failed to lower privileges");

2139

}

2040

2140

}

2041

2141

}

2042

2142

2066

2166

goto end;

2067

2167

}

2068

2168

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

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

}

2169

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

2170

}

2171

run_network_hooks("start", interfaces_hooks != NULL ?

2172

interfaces_hooks : "", delay);

2077

2173

}

2078

2174

2079

2175

if(not debug){

2167

2263

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

2168

2264

direntries[i]->d_name);

2169

2265

if(ret_errno != 0){

2266

errno = ret_errno;

2170

2267

perror_plus("argz_add");

2171

2268

continue;

2172

2269

}

2206

2303

break;

2207

2304

}

2208

2305

bool interface_was_up = interface_is_up(interface);

2209

ret = bring_up_interface(interface, delay);

2306

errno = bring_up_interface(interface, delay);

2210

2307

if(not interface_was_up){

2211

if(ret != 0){

2212

errno = ret;

2308

if(errno != 0){

2213

2309

perror_plus("Failed to bring up interface");

2214

2310

} else {

2215

ret_errno = argz_add(&interfaces_to_take_down,

2216

&interfaces_to_take_down_size,

2217

interface);

2311

errno = argz_add(&interfaces_to_take_down,

2312

&interfaces_to_take_down_size,

2313

interface);

2314

if(errno != 0){

2315

perror_plus("argz_add");

2316

}

2218

2317

}

2219

2318

}

2220

2319

}

2249

2348

goto end;

2250

2349

}

2251

2350

2252

if(mkdtemp(tempdir) == NULL){

2351

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

2352

tempdir = mkdtemp(run_tempdir);

2353

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

2354

if(debug){

2355

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

2356

run_tempdir, old_tempdir);

2357

}

2358

tempdir = mkdtemp(old_tempdir);

2359

}

2360

if(tempdir == NULL){

2253

2361

perror_plus("mkdtemp");

2254

2362

goto end;

2255

2363

}

2256

tempdir_created = true;

2257

2364

2258

2365

if(quit_now){

2259

2366

goto end;

2331

2438

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

2332

2439

(int)retry_interval);

2333

2440

}

2334

sleep((int)retry_interval);

2441

sleep((unsigned int)retry_interval);

2335

2442

}

2336

2443

2337

if (not quit_now){

2444

if(not quit_now){

2338

2445

exitcode = EXIT_SUCCESS;

2339

2446

}

2340

2447

2395

2502

if(debug){

2396

2503

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

2397

2504

}

2398

2505

2399

2506

ret = avahi_loop_with_timeout(simple_poll,

2400

2507

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

2401

2508

if(debug){

2442

2549

}

2443

2550

}

2444

2551

2445

/* Re-raise priviliges */

2552

/* Re-raise privileges */

2446

2553

{

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();

2554

ret_errno = raise_privileges();

2555

if(ret_errno != 0){

2556

perror_plus("Failed to raise privileges");

2557

} else {

2558

2559

/* Run network hooks */

2560

run_network_hooks("stop", interfaces_hooks != NULL ?

2561

interfaces_hooks : "", delay);

2562

2563

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

2564

{

2565

char *interface = NULL;

2566

while((interface=argz_next(interfaces_to_take_down,

2567

interfaces_to_take_down_size,

2568

interface))){

2569

ret_errno = take_down_interface(interface);

2570

if(ret_errno != 0){

2571

errno = ret_errno;

2572

perror_plus("Failed to take down interface");

2573

}

2574

}

2575

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

2576

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

2577

" down\n");

2578

}

2579

}

2580

}

2581

2582

ret_errno = lower_privileges_permanently();

2583

if(ret_errno != 0){

2584

perror_plus("Failed to lower privileges permanently");

2585

}

2472

2586

}

2473

2587

2474

2588

free(interfaces_to_take_down);

2475

2589

free(interfaces_hooks);

2476

2590

2477

2591

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

2478

if(tempdir_created){

2592

if(tempdir != NULL){

2479

2593

struct dirent **direntries = NULL;

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);

2594

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

2595

O_NOFOLLOW));

2596

if(tempdir_fd == -1){

2597

perror_plus("open");

2598

} else {

2599

#ifdef __GLIBC__

2600

#if __GLIBC_PREREQ(2, 15)

2601

int numentries = scandirat(tempdir_fd, ".", &direntries,

2602

notdotentries, alphasort);

2603

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

2604

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

2605

alphasort);

2606

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

2607

#else /* not __GLIBC__ */

2608

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

2609

alphasort);

2610

#endif /* not __GLIBC__ */

2611

if(numentries > 0){

2612

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

2613

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

2614

if(ret == -1){

2615

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

2616

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

2617

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

2618

}

2619

}

2620

2621

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

2622

free(direntries);

2623

if(numentries == -1){

2624

perror_plus("scandir");

2625

}

2626

ret = rmdir(tempdir);

2627

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

2628

perror_plus("rmdir");

2629

}

2499

2630

}

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");

2631

TEMP_FAILURE_RETRY(close(tempdir_fd));

2510

2632

}

2511

2633

}

2512

2634