/mandos/release : revision 237.16.10

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

41

42

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

43

stdout, ferror(), remove() */

44

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

44

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

45

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

46

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

47

strtof(), abort() */

61

*/

62

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

63

strtoimax() */

64

#include <assert.h> /* assert() */

64

65

#include <errno.h> /* perror(), errno,

65

66

program_invocation_short_name */

66

67

#include <time.h> /* nanosleep(), time(), sleep() */

72

73

*/

73

74

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

74

75

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

75

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

76

setgid(), pause() */

76

77

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

77

78

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

78

79

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

86

87

EX_NOHOST, EX_IOERR, EX_PROTOCOL */

87

88

#include <sys/wait.h> /* waitpid(), WIFEXITED(),

88

89

WEXITSTATUS(), WTERMSIG() */

89

#include <grp.h> /* setgroups() */

90

#include <argz.h> /* argz_add_sep(), argz_next(),

91

argz_delete(), argz_append(),

92

argz_stringify(), argz_add(),

93

argz_count() */

94

90

95

91

#ifdef __linux__

96

92

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

138

134

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

139

135

char *connect_to = NULL;

140

136

const char *hookdir = HOOKDIR;

141

uid_t uid = 65534;

142

gid_t gid = 65534;

143

137

144

138

/* Doubly linked list that need to be circularly linked when used */

145

139

typedef struct server{

146

140

const char *ip;

147

in_port_t port;

141

uint16_t port;

148

142

AvahiIfIndex if_index;

149

143

int af;

150

144

struct timespec last_seen;

154

148

155

149

/* Used for passing in values through the Avahi callback functions */

156

150

typedef struct {

151

AvahiSimplePoll *simple_poll;

157

152

AvahiServer *server;

158

153

gnutls_certificate_credentials_t cred;

159

154

unsigned int dh_bits;

163

158

server *current_server;

164

159

} mandos_context;

165

160

166

/* global so signal handler can reach it*/

167

AvahiSimplePoll *simple_poll;

168

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

169

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

170

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

161

/* global context so signal handler can reach it*/

162

mandos_context mc = { .simple_poll = NULL, .server = NULL,

163

.dh_bits = 1024, .priority = "SECURE256"

164

":!CTYPE-X.509:+CTYPE-OPENPGP",

165

.current_server = NULL };

171

166

172

167

sig_atomic_t quit_now = 0;

173

168

int signal_received = 0;

174

169

175

170

/* Function to use when printing errors */

176

171

void perror_plus(const char *print_text){

177

int e = errno;

178

172

fprintf(stderr, "Mandos plugin %s: ",

179

173

program_invocation_short_name);

180

errno = e;

181

174

perror(print_text);

182

175

}

183

176

184

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

185

177

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

186

178

va_list ap;

187

179

va_start (ap, format);

209

201

}

210

202

211

203

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

212

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

213

int af){

204

int add_server(const char *ip, uint16_t port, AvahiIfIndex if_index,

205

int af){

214

206

int ret;

215

207

server *new_server = malloc(sizeof(server));

216

208

if(new_server == NULL){

217

209

perror_plus("malloc");

218

return false;

210

return -1;

219

211

}

220

212

*new_server = (server){ .ip = strdup(ip),

221

213

.port = port,

223

215

.af = af };

224

216

if(new_server->ip == NULL){

225

217

perror_plus("strdup");

226

return false;

218

return -1;

227

219

}

228

220

/* Special case of first server */

229

221

if (mc.current_server == NULL){

240

232

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

241

233

if(ret == -1){

242

234

perror_plus("clock_gettime");

243

return false;

235

return -1;

244

236

}

245

return true;

237

return 0;

246

238

}

247

239

248

240

/*

253

245

gpgme_error_t rc;

254

246

gpgme_engine_info_t engine_info;

255

247

248

256

249

/*

257

250

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

258

251

*/

468

461

}

469

462

470

463

static const char * safer_gnutls_strerror(int value){

471

const char *ret = gnutls_strerror(value);

464

const char *ret = gnutls_strerror(value); /* Spurious warning from

465

-Wunreachable-code */

472

466

if(ret == NULL)

473

467

ret = "(unknown)";

474

468

return ret;

619

613

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

620

614

621

615

/* Called when a Mandos server is found */

622

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

616

static int start_mandos_communication(const char *ip, uint16_t port,

623

617

AvahiIfIndex if_index,

624

618

int af){

625

619

int ret, tcp_sd = -1;

664

658

665

659

if(debug){

666

660

fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"

667

PRIuMAX "\n", ip, (uintmax_t)port);

661

PRIu16 "\n", ip, port);

668

662

}

669

663

670

664

tcp_sd = socket(pf, SOCK_STREAM, 0);

701

695

goto mandos_end;

702

696

}

703

697

if(af == AF_INET6){

704

to.in6.sin6_port = htons(port);

698

to.in6.sin6_port = htons(port); /* Spurious warnings from

699

-Wconversion and

700

-Wunreachable-code */

701

705

702

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

706

703

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

707

704

-Wunreachable-code*/

731

728

if(if_indextoname((unsigned int)if_index, interface) == NULL){

732

729

perror_plus("if_indextoname");

733

730

} else {

734

fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX

735

"\n", ip, interface, (uintmax_t)port);

731

fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIu16

732

"\n", ip, interface, port);

736

733

}

737

734

} else {

738

fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",

739

ip, (uintmax_t)port);

735

fprintf_plus(stderr, "Connection to: %s, port %" PRIu16 "\n",

736

ip, port);

740

737

}

741

738

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

742

739

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

820

817

goto mandos_end;

821

818

}

822

819

823

/* This casting via intptr_t is to eliminate warning about casting

824

an int to a pointer type. This is exactly how the GnuTLS Guile

825

function "set-session-transport-fd!" does it. */

826

gnutls_transport_set_ptr(session,

827

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

820

/* Spurious warning from -Wint-to-pointer-cast */

821

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

828

822

829

823

if(quit_now){

830

824

errno = EINTR;

1003

997

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1004

998

flags,

1005

999

AVAHI_GCC_UNUSED void* userdata){

1006

if(r == NULL){

1007

return;

1008

}

1000

assert(r);

1009

1001

1010

1002

/* Called whenever a service has been resolved successfully or

1011

1003

timed out */

1032

1024

PRIdMAX ") on port %" PRIu16 "\n", name,

1033

1025

host_name, ip, (intmax_t)interface, port);

1034

1026

}

1035

int ret = start_mandos_communication(ip, (in_port_t)port,

1036

interface,

1027

int ret = start_mandos_communication(ip, port, interface,

1037

1028

avahi_proto_to_af(proto));

1038

1029

if(ret == 0){

1039

avahi_simple_poll_quit(simple_poll);

1030

avahi_simple_poll_quit(mc.simple_poll);

1040

1031

} else {

1041

if(not add_server(ip, (in_port_t)port, interface,

1042

avahi_proto_to_af(proto))){

1043

fprintf_plus(stderr, "Failed to add server \"%s\" to server"

1044

" list\n", name);

1045

}

1032

ret = add_server(ip, port, interface,

1033

avahi_proto_to_af(proto));

1046

1034

}

1047

1035

}

1048

1036

}

1059

1047

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1060

1048

flags,

1061

1049

AVAHI_GCC_UNUSED void* userdata){

1062

if(b == NULL){

1063

return;

1064

}

1050

assert(b);

1065

1051

1066

1052

/* Called whenever a new services becomes available on the LAN or

1067

1053

is removed from the LAN */

1076

1062

1077

1063

fprintf_plus(stderr, "(Avahi browser) %s\n",

1078

1064

avahi_strerror(avahi_server_errno(mc.server)));

1079

avahi_simple_poll_quit(simple_poll);

1065

avahi_simple_poll_quit(mc.simple_poll);

1080

1066

return;

1081

1067

1082

1068

case AVAHI_BROWSER_NEW:

1115

1101

signal_received = sig;

1116

1102

int old_errno = errno;

1117

1103

/* set main loop to exit */

1118

if(simple_poll != NULL){

1119

avahi_simple_poll_quit(simple_poll);

1104

if(mc.simple_poll != NULL){

1105

avahi_simple_poll_quit(mc.simple_poll);

1120

1106

}

1121

1107

errno = old_errno;

1122

1108

}

1123

1109

1124

1110

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

1125

1111

int ret;

1126

error_t ret_errno;

1127

1112

1128

1113

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

1129

1114

if(s < 0){

1130

ret_errno = errno;

1131

1115

perror_plus("socket");

1132

errno = ret_errno;

1133

1116

return false;

1134

1117

}

1135

1118

strcpy(ifr->ifr_name, ifname);

1136

1119

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1137

1120

if(ret == -1){

1138

1121

if(debug){

1139

ret_errno = errno;

1140

1122

perror_plus("ioctl SIOCGIFFLAGS");

1141

errno = ret_errno;

1142

1123

}

1143

1124

return false;

1144

1125

}

1213

1194

}

1214

1195

1215

1196

/*

1216

* This function determines if a network interface is up.

1217

*/

1218

bool interface_is_up(const char *interface){

1219

struct ifreq ifr;

1220

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

1221

if(debug){

1222

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

1223

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

1224

}

1225

return false;

1226

}

1227

1228

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

1229

}

1230

1231

/*

1232

* This function determines if a network interface is running

1233

*/

1234

bool interface_is_running(const char *interface){

1235

struct ifreq ifr;

1236

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

1237

if(debug){

1238

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

1239

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

1240

}

1241

return false;

1242

}

1243

1244

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

1197

* This function determines if a directory entry in /sys/class/net

1198

* corresponds to an acceptable network device which is up.

1199

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

1200

*/

1201

int up_interface(const struct dirent *if_entry){

1202

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

1203

return 0;

1204

}

1205

1206

struct ifreq ifr;

1207

if(not get_flags(if_entry->d_name, &ifr)){

1208

if(debug){

1209

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

1210

"\"%s\"\n", if_entry->d_name);

1211

}

1212

return 0;

1213

}

1214

1215

/* Reject down interfaces */

1216

if(not (ifr.ifr_flags & IFF_UP)){

1217

if(debug){

1218

fprintf_plus(stderr, "Rejecting down interface \"%s\"\n",

1219

if_entry->d_name);

1220

}

1221

return 0;

1222

}

1223

1224

/* Reject non-running interfaces */

1225

if(not (ifr.ifr_flags & IFF_RUNNING)){

1226

if(debug){

1227

fprintf_plus(stderr, "Rejecting non-running interface \"%s\"\n",

1228

if_entry->d_name);

1229

}

1230

return 0;

1231

}

1232

1233

if(not good_flags(if_entry->d_name, &ifr)){

1234

return 0;

1235

}

1236

return 1;

1245

1237

}

1246

1238

1247

1239

int notdotentries(const struct dirent *direntry){

1309

1301

}

1310

1302

return 0;

1311

1303

}

1312

if(debug){

1313

fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",

1314

direntry->d_name);

1315

}

1316

1304

return 1;

1317

1305

}

1318

1306

1364

1352

mc.current_server->if_index,

1365

1353

mc.current_server->af);

1366

1354

if(ret == 0){

1367

avahi_simple_poll_quit(simple_poll);

1355

avahi_simple_poll_quit(mc.simple_poll);

1368

1356

return 0;

1369

1357

}

1370

1358

ret = clock_gettime(CLOCK_MONOTONIC,

1388

1376

}

1389

1377

}

1390

1378

1391

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

1392

error_t raise_privileges(void){

1393

error_t old_errno = errno;

1394

error_t ret_errno = 0;

1395

if(seteuid(0) == -1){

1396

ret_errno = errno;

1397

perror_plus("seteuid");

1398

}

1399

errno = old_errno;

1400

return ret_errno;

1401

}

1402

1403

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

1404

error_t raise_privileges_permanently(void){

1405

error_t old_errno = errno;

1406

error_t ret_errno = raise_privileges();

1407

if(ret_errno != 0){

1408

errno = old_errno;

1409

return ret_errno;

1410

}

1411

if(setuid(0) == -1){

1412

ret_errno = errno;

1413

perror_plus("seteuid");

1414

}

1415

errno = old_errno;

1416

return ret_errno;

1417

}

1418

1419

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

1420

error_t lower_privileges(void){

1421

error_t old_errno = errno;

1422

error_t ret_errno = 0;

1423

if(seteuid(uid) == -1){

1424

ret_errno = errno;

1425

perror_plus("seteuid");

1426

}

1427

errno = old_errno;

1428

return ret_errno;

1429

}

1430

1431

/* Lower privileges permanently */

1432

error_t lower_privileges_permanently(void){

1433

error_t old_errno = errno;

1434

error_t ret_errno = 0;

1435

if(setuid(uid) == -1){

1436

ret_errno = errno;

1437

perror_plus("setuid");

1438

}

1439

errno = old_errno;

1440

return ret_errno;

1441

}

1442

1443

1379

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

1444

1380

const float delay){

1445

1381

struct dirent **direntries;

1448

1384

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

1449

1385

alphasort);

1450

1386

if(numhooks == -1){

1451

if(errno == ENOENT){

1452

if(debug){

1453

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

1454

" found\n", hookdir);

1455

}

1456

} else {

1457

perror_plus("scandir");

1458

}

1387

perror_plus("scandir");

1459

1388

} else {

1460

1389

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

1461

1390

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

1462

direntry = direntries[i];

1391

direntry = direntries[0];

1463

1392

char *fullname = NULL;

1464

1393

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

1465

1394

if(ret < 0){

1466

1395

perror_plus("asprintf");

1467

1396

continue;

1468

1397

}

1469

if(debug){

1470

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

1471

direntry->d_name);

1472

}

1473

1398

pid_t hook_pid = fork();

1474

1399

if(hook_pid == 0){

1475

1400

/* Child */

1476

/* Raise privileges */

1477

raise_privileges_permanently();

1478

/* Set group */

1479

errno = 0;

1480

ret = setgid(0);

1481

if(ret == -1){

1482

perror_plus("setgid");

1483

}

1484

/* Reset supplementary groups */

1485

errno = 0;

1486

ret = setgroups(0, NULL);

1487

if(ret == -1){

1488

perror_plus("setgroups");

1489

}

1490

1401

dup2(devnull, STDIN_FILENO);

1491

1402

close(devnull);

1492

1403

dup2(STDERR_FILENO, STDOUT_FILENO);

1493

1404

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

1494

1405

if(ret == -1){

1495

1406

perror_plus("setenv");

1496

_exit(EX_OSERR);

1407

return false;

1497

1408

}

1498

1409

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

1499

1410

if(ret == -1){

1500

1411

perror_plus("setenv");

1501

_exit(EX_OSERR);

1412

return false;

1502

1413

}

1503

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

1414

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

1504

1415

if(ret == -1){

1505

1416

perror_plus("setenv");

1506

_exit(EX_OSERR);

1417

return false;

1507

1418

}

1508

1419

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

1509

1420

if(ret == -1){

1510

1421

perror_plus("setenv");

1511

_exit(EX_OSERR);

1422

return false;

1512

1423

}

1513

1424

char *delaystring;

1514

1425

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

1515

1426

if(ret == -1){

1516

1427

perror_plus("asprintf");

1517

_exit(EX_OSERR);

1428

return false;

1518

1429

}

1519

1430

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

1520

1431

if(ret == -1){

1521

1432

free(delaystring);

1522

1433

perror_plus("setenv");

1523

_exit(EX_OSERR);

1434

return false;

1524

1435

}

1525

1436

free(delaystring);

1526

if(connect_to != NULL){

1527

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

1528

if(ret == -1){

1529

perror_plus("setenv");

1530

_exit(EX_OSERR);

1531

}

1532

}

1533

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

1534

perror_plus("execl");

1535

_exit(EXIT_FAILURE);

1536

}

1437

ret = execl(fullname, direntry->d_name, mode, NULL);

1438

perror_plus("execl");

1537

1439

} else {

1538

1440

int status;

1539

1441

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

1563

1465

}

1564

1466

}

1565

1467

free(fullname);

1566

if(debug){

1567

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

1568

direntry->d_name);

1468

if(quit_now){

1469

break;

1569

1470

}

1570

1471

}

1571

1472

close(devnull);

1573

1474

return true;

1574

1475

}

1575

1476

1576

error_t bring_up_interface(const char *const interface,

1577

const float delay){

1578

int sd = -1;

1579

error_t old_errno = errno;

1580

error_t ret_errno = 0;

1581

int ret, ret_setflags;

1582

struct ifreq network;

1583

unsigned int if_index = if_nametoindex(interface);

1584

if(if_index == 0){

1585

fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);

1586

errno = old_errno;

1587

return ENXIO;

1588

}

1589

1590

if(quit_now){

1591

errno = old_errno;

1592

return EINTR;

1593

}

1594

1595

if(not interface_is_up(interface)){

1596

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

1597

ret_errno = errno;

1598

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

1599

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

1600

return ret_errno;

1601

}

1602

network.ifr_flags |= IFF_UP;

1603

1604

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1605

if(sd < 0){

1606

ret_errno = errno;

1607

perror_plus("socket");

1608

errno = old_errno;

1609

return ret_errno;

1610

}

1611

1612

if(quit_now){

1613

close(sd);

1614

errno = old_errno;

1615

return EINTR;

1616

}

1617

1618

if(debug){

1619

fprintf_plus(stderr, "Bringing up interface \"%s\"\n",

1620

interface);

1621

}

1622

1623

/* Raise priviliges */

1624

raise_privileges();

1625

1626

#ifdef __linux__

1627

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1628

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

1629

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

1630

bool restore_loglevel = true;

1631

if(ret_linux == -1){

1632

restore_loglevel = false;

1633

perror_plus("klogctl");

1634

}

1635

#endif /* __linux__ */

1636

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

1637

ret_errno = errno;

1638

#ifdef __linux__

1639

if(restore_loglevel){

1640

ret_linux = klogctl(7, NULL, 0);

1641

if(ret_linux == -1){

1642

perror_plus("klogctl");

1643

}

1644

}

1645

#endif /* __linux__ */

1646

1647

/* Lower privileges */

1648

lower_privileges();

1649

1650

/* Close the socket */

1651

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

1652

if(ret == -1){

1653

perror_plus("close");

1654

}

1655

1656

if(ret_setflags == -1){

1657

errno = ret_errno;

1658

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1659

errno = old_errno;

1660

return ret_errno;

1661

}

1662

} else if(debug){

1663

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

1664

interface);

1665

}

1666

1667

/* Sleep checking until interface is running.

1668

Check every 0.25s, up to total time of delay */

1669

for(int i=0; i < delay * 4; i++){

1670

if(interface_is_running(interface)){

1671

break;

1672

}

1673

struct timespec sleeptime = { .tv_nsec = 250000000 };

1674

ret = nanosleep(&sleeptime, NULL);

1675

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

1676

perror_plus("nanosleep");

1677

}

1678

}

1679

1680

errno = old_errno;

1681

return 0;

1682

}

1683

1684

error_t take_down_interface(const char *const interface){

1685

int sd = -1;

1686

error_t old_errno = errno;

1687

error_t ret_errno = 0;

1688

int ret, ret_setflags;

1689

struct ifreq network;

1690

unsigned int if_index = if_nametoindex(interface);

1691

if(if_index == 0){

1692

fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);

1693

errno = old_errno;

1694

return ENXIO;

1695

}

1696

if(interface_is_up(interface)){

1697

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

1698

ret_errno = errno;

1699

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

1700

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

1701

return ret_errno;

1702

}

1703

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

1704

1705

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1706

if(sd < 0){

1707

ret_errno = errno;

1708

perror_plus("socket");

1709

errno = old_errno;

1710

return ret_errno;

1711

}

1712

1713

if(debug){

1714

fprintf_plus(stderr, "Taking down interface \"%s\"\n",

1715

interface);

1716

}

1717

1718

/* Raise priviliges */

1719

raise_privileges();

1720

1721

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

1722

ret_errno = errno;

1723

1724

/* Lower privileges */

1725

lower_privileges();

1726

1727

/* Close the socket */

1728

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

1729

if(ret == -1){

1730

perror_plus("close");

1731

}

1732

1733

if(ret_setflags == -1){

1734

errno = ret_errno;

1735

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1736

errno = old_errno;

1737

return ret_errno;

1738

}

1739

} else if(debug){

1740

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

1741

interface);

1742

}

1743

1744

errno = old_errno;

1745

return 0;

1746

}

1747

1748

1477

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

1749

1478

AvahiSServiceBrowser *sb = NULL;

1750

error_t ret_errno;

1479

int error;

1751

1480

int ret;

1752

1481

intmax_t tmpmax;

1753

1482

char *tmp;

1754

1483

int exitcode = EXIT_SUCCESS;

1755

char *interfaces = NULL;

1756

size_t interfaces_size = 0;

1757

char *interfaces_to_take_down = NULL;

1758

size_t interfaces_to_take_down_size = 0;

1484

const char *interface = "";

1485

struct ifreq network;

1486

int sd = -1;

1487

bool take_down_interface = false;

1488

uid_t uid;

1489

gid_t gid;

1759

1490

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

1760

1491

bool tempdir_created = false;

1761

1492

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1762

1493

const char *seckey = PATHDIR "/" SECKEY;

1763

1494

const char *pubkey = PATHDIR "/" PUBKEY;

1764

char *interfaces_hooks = NULL;

1765

size_t interfaces_hooks_size = 0;

1766

1495

1767

1496

bool gnutls_initialized = false;

1768

1497

bool gpgme_initialized = false;

1830

1559

.group = 2 },

1831

1560

{ .name = "retry", .key = 132,

1832

1561

.arg = "SECONDS",

1833

.doc = "Retry interval used when denied by the Mandos server",

1562

.doc = "Retry interval used when denied by the mandos server",

1834

1563

.group = 2 },

1835

1564

{ .name = "network-hook-dir", .key = 133,

1836

1565

.arg = "DIR",

1859

1588

connect_to = arg;

1860

1589

break;

1861

1590

case 'i': /* --interface */

1862

ret_errno = argz_add_sep(&interfaces, &interfaces_size, arg,

1863

(int)',');

1864

if(ret_errno != 0){

1865

argp_error(state, "%s", strerror(ret_errno));

1866

}

1591

interface = arg;

1867

1592

break;

1868

1593

case 's': /* --seckey */

1869

1594

seckey = arg;

1912

1637

argp_state_help(state, state->out_stream,

1913

1638

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1914

1639

case 'V': /* --version */

1640

fprintf_plus(state->out_stream,

1641

"Mandos plugin mandos-client: ");

1915

1642

fprintf_plus(state->out_stream, "%s\n", argp_program_version);

1916

1643

exit(argp_err_exit_status);

1917

1644

break;

1945

1672

{

1946

1673

/* Work around Debian bug #633582:

1947

1674

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

1675

struct stat st;

1948

1676

1949

1677

/* Re-raise priviliges */

1950

if(raise_privileges() == 0){

1951

struct stat st;

1952

1953

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

1954

int seckey_fd = open(seckey, O_RDONLY);

1955

if(seckey_fd == -1){

1956

perror_plus("open");

1957

} else {

1958

ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));

1959

if(ret == -1){

1960

perror_plus("fstat");

1961

} else {

1962

if(S_ISREG(st.st_mode)

1963

and st.st_uid == 0 and st.st_gid == 0){

1964

ret = fchown(seckey_fd, uid, gid);

1965

if(ret == -1){

1966

perror_plus("fchown");

1967

}

1968

}

1969

}

1970

TEMP_FAILURE_RETRY(close(seckey_fd));

1971

}

1972

}

1973

1974

if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){

1975

int pubkey_fd = open(pubkey, O_RDONLY);

1976

if(pubkey_fd == -1){

1977

perror_plus("open");

1978

} else {

1979

ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));

1980

if(ret == -1){

1981

perror_plus("fstat");

1982

} else {

1983

if(S_ISREG(st.st_mode)

1984

and st.st_uid == 0 and st.st_gid == 0){

1985

ret = fchown(pubkey_fd, uid, gid);

1986

if(ret == -1){

1987

perror_plus("fchown");

1988

}

1989

}

1990

}

1991

TEMP_FAILURE_RETRY(close(pubkey_fd));

1992

}

1993

}

1994

1995

/* Lower privileges */

1996

errno = 0;

1997

ret = seteuid(uid);

1998

if(ret == -1){

1999

perror_plus("seteuid");

2000

}

2001

}

2002

}

2003

2004

/* Remove empty interface names */

2005

{

2006

char *interface = NULL;

2007

while((interface = argz_next(interfaces, interfaces_size,

2008

interface))){

2009

if(if_nametoindex(interface) == 0){

2010

if(interface[0] != '\0' and strcmp(interface, "none") != 0){

2011

fprintf_plus(stderr, "Not using nonexisting interface"

2012

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

2013

}

2014

argz_delete(&interfaces, &interfaces_size, interface);

2015

interface = NULL;

2016

}

1678

errno = 0;

1679

ret = seteuid(0);

1680

if(ret == -1){

1681

perror_plus("seteuid");

1682

}

1683

1684

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

1685

int seckey_fd = open(seckey, O_RDONLY);

1686

if(seckey_fd == -1){

1687

perror_plus("open");

1688

} else {

1689

ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));

1690

if(ret == -1){

1691

perror_plus("fstat");

1692

} else {

1693

if(S_ISREG(st.st_mode)

1694

and st.st_uid == 0 and st.st_gid == 0){

1695

ret = fchown(seckey_fd, uid, gid);

1696

if(ret == -1){

1697

perror_plus("fchown");

1698

}

1699

}

1700

}

1701

TEMP_FAILURE_RETRY(close(seckey_fd));

1702

}

1703

}

1704

1705

if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){

1706

int pubkey_fd = open(pubkey, O_RDONLY);

1707

if(pubkey_fd == -1){

1708

perror_plus("open");

1709

} else {

1710

ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));

1711

if(ret == -1){

1712

perror_plus("fstat");

1713

} else {

1714

if(S_ISREG(st.st_mode)

1715

and st.st_uid == 0 and st.st_gid == 0){

1716

ret = fchown(pubkey_fd, uid, gid);

1717

if(ret == -1){

1718

perror_plus("fchown");

1719

}

1720

}

1721

}

1722

TEMP_FAILURE_RETRY(close(pubkey_fd));

1723

}

1724

}

1725

1726

/* Lower privileges */

1727

errno = 0;

1728

ret = seteuid(uid);

1729

if(ret == -1){

1730

perror_plus("seteuid");

2017

1731

}

2018

1732

}

2019

1733

2020

1734

/* Run network hooks */

2021

1735

{

2022

2023

if(interfaces != NULL){

2024

interfaces_hooks = malloc(interfaces_size);

2025

if(interfaces_hooks == NULL){

2026

perror_plus("malloc");

2027

goto end;

2028

}

2029

memcpy(interfaces_hooks, interfaces, interfaces_size);

2030

interfaces_hooks_size = interfaces_size;

2031

argz_stringify(interfaces_hooks, interfaces_hooks_size,

2032

(int)',');

1736

/* Re-raise priviliges */

1737

errno = 0;

1738

ret = seteuid(0);

1739

if(ret == -1){

1740

perror_plus("seteuid");

2033

1741

}

2034

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

2035

interfaces_hooks : "", delay)){

1742

if(not run_network_hooks("start", interface, delay)){

2036

1743

goto end;

2037

1744

}

1745

/* Lower privileges */

1746

errno = 0;

1747

ret = seteuid(uid);

1748

if(ret == -1){

1749

perror_plus("seteuid");

1750

}

2038

1751

}

2039

1752

2040

1753

if(not debug){

2041

1754

avahi_set_log_function(empty_log);

2042

1755

}

2043

1756

1757

if(interface[0] == '\0'){

1758

struct dirent **direntries;

1759

/* First look for interfaces that are up */

1760

ret = scandir(sys_class_net, &direntries, up_interface,

1761

alphasort);

1762

if(ret == 0){

1763

/* No up interfaces, look for any good interfaces */

1764

free(direntries);

1765

ret = scandir(sys_class_net, &direntries, good_interface,

1766

alphasort);

1767

}

1768

if(ret >= 1){

1769

/* Pick the first interface returned */

1770

interface = strdup(direntries[0]->d_name);

1771

if(debug){

1772

fprintf_plus(stderr, "Using interface \"%s\"\n", interface);

1773

}

1774

if(interface == NULL){

1775

perror_plus("malloc");

1776

free(direntries);

1777

exitcode = EXIT_FAILURE;

1778

goto end;

1779

}

1780

free(direntries);

1781

} else {

1782

free(direntries);

1783

fprintf_plus(stderr, "Could not find a network interface\n");

1784

exitcode = EXIT_FAILURE;

1785

goto end;

1786

}

1787

}

1788

2044

1789

/* Initialize Avahi early so avahi_simple_poll_quit() can be called

2045

1790

from the signal handler */

2046

1791

/* Initialize the pseudo-RNG for Avahi */

2047

1792

srand((unsigned int) time(NULL));

2048

simple_poll = avahi_simple_poll_new();

2049

if(simple_poll == NULL){

1793

mc.simple_poll = avahi_simple_poll_new();

1794

if(mc.simple_poll == NULL){

2050

1795

fprintf_plus(stderr,

2051

1796

"Avahi: Failed to create simple poll object.\n");

2052

1797

exitcode = EX_UNAVAILABLE;

2116

1861

}

2117

1862

}

2118

1863

2119

/* If no interfaces were specified, make a list */

2120

if(interfaces == NULL){

2121

struct dirent **direntries;

2122

/* Look for any good interfaces */

2123

ret = scandir(sys_class_net, &direntries, good_interface,

2124

alphasort);

2125

if(ret >= 1){

2126

/* Add all found interfaces to interfaces list */

2127

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

2128

ret_errno = argz_add(&interfaces, &interfaces_size,

2129

direntries[i]->d_name);

2130

if(ret_errno != 0){

2131

perror_plus("argz_add");

2132

continue;

2133

}

2134

if(debug){

2135

fprintf_plus(stderr, "Will use interface \"%s\"\n",

2136

direntries[i]->d_name);

2137

}

2138

}

2139

free(direntries);

2140

} else {

2141

free(direntries);

2142

fprintf_plus(stderr, "Could not find a network interface\n");

2143

exitcode = EXIT_FAILURE;

2144

goto end;

2145

}

2146

}

2147

2148

/* If we only got one interface, explicitly use only that one */

2149

if(argz_count(interfaces, interfaces_size) == 1){

2150

if(debug){

2151

fprintf_plus(stderr, "Using only interface \"%s\"\n",

2152

interfaces);

2153

}

2154

if_index = (AvahiIfIndex)if_nametoindex(interfaces);

2155

}

2156

2157

/* Bring up interfaces which are down */

2158

if(not (argz_count(interfaces, interfaces_size) == 1

2159

and strcmp(interfaces, "none") == 0)){

2160

char *interface = NULL;

2161

while((interface = argz_next(interfaces, interfaces_size,

2162

interface))){

2163

bool interface_was_up = interface_is_up(interface);

2164

ret = bring_up_interface(interface, delay);

2165

if(not interface_was_up){

2166

if(ret != 0){

2167

errno = ret;

2168

perror_plus("Failed to bring up interface");

2169

} else {

2170

ret_errno = argz_add(&interfaces_to_take_down,

2171

&interfaces_to_take_down_size,

2172

interface);

2173

}

2174

}

2175

}

2176

free(interfaces);

2177

interfaces = NULL;

2178

interfaces_size = 0;

2179

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

2180

fprintf_plus(stderr, "No interfaces were brought up\n");

1864

/* If the interface is down, bring it up */

1865

if(strcmp(interface, "none") != 0){

1866

if_index = (AvahiIfIndex) if_nametoindex(interface);

1867

if(if_index == 0){

1868

fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);

1869

exitcode = EX_UNAVAILABLE;

1870

goto end;

1871

}

1872

1873

if(quit_now){

1874

goto end;

1875

}

1876

1877

/* Re-raise priviliges */

1878

errno = 0;

1879

ret = seteuid(0);

1880

if(ret == -1){

1881

perror_plus("seteuid");

1882

}

1883

1884

#ifdef __linux__

1885

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1886

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

1887

ret = klogctl(8, NULL, 5);

1888

bool restore_loglevel = true;

1889

if(ret == -1){

1890

restore_loglevel = false;

1891

perror_plus("klogctl");

1892

}

1893

#endif /* __linux__ */

1894

1895

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1896

if(sd < 0){

1897

perror_plus("socket");

1898

exitcode = EX_OSERR;

1899

#ifdef __linux__

1900

if(restore_loglevel){

1901

ret = klogctl(7, NULL, 0);

1902

if(ret == -1){

1903

perror_plus("klogctl");

1904

}

1905

}

1906

#endif /* __linux__ */

1907

/* Lower privileges */

1908

errno = 0;

1909

ret = seteuid(uid);

1910

if(ret == -1){

1911

perror_plus("seteuid");

1912

}

1913

goto end;

1914

}

1915

strcpy(network.ifr_name, interface);

1916

ret = ioctl(sd, SIOCGIFFLAGS, &network);

1917

if(ret == -1){

1918

perror_plus("ioctl SIOCGIFFLAGS");

1919

#ifdef __linux__

1920

if(restore_loglevel){

1921

ret = klogctl(7, NULL, 0);

1922

if(ret == -1){

1923

perror_plus("klogctl");

1924

}

1925

}

1926

#endif /* __linux__ */

1927

exitcode = EX_OSERR;

1928

/* Lower privileges */

1929

errno = 0;

1930

ret = seteuid(uid);

1931

if(ret == -1){

1932

perror_plus("seteuid");

1933

}

1934

goto end;

1935

}

1936

if((network.ifr_flags & IFF_UP) == 0){

1937

network.ifr_flags |= IFF_UP;

1938

take_down_interface = true;

1939

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

1940

if(ret == -1){

1941

take_down_interface = false;

1942

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1943

exitcode = EX_OSERR;

1944

#ifdef __linux__

1945

if(restore_loglevel){

1946

ret = klogctl(7, NULL, 0);

1947

if(ret == -1){

1948

perror_plus("klogctl");

1949

}

1950

}

1951

#endif /* __linux__ */

1952

/* Lower privileges */

1953

errno = 0;

1954

ret = seteuid(uid);

1955

if(ret == -1){

1956

perror_plus("seteuid");

1957

}

1958

goto end;

1959

}

1960

}

1961

/* Sleep checking until interface is running.

1962

Check every 0.25s, up to total time of delay */

1963

for(int i=0; i < delay * 4; i++){

1964

ret = ioctl(sd, SIOCGIFFLAGS, &network);

1965

if(ret == -1){

1966

perror_plus("ioctl SIOCGIFFLAGS");

1967

} else if(network.ifr_flags & IFF_RUNNING){

1968

break;

1969

}

1970

struct timespec sleeptime = { .tv_nsec = 250000000 };

1971

ret = nanosleep(&sleeptime, NULL);

1972

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

1973

perror_plus("nanosleep");

1974

}

1975

}

1976

if(not take_down_interface){

1977

/* We won't need the socket anymore */

1978

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

1979

if(ret == -1){

1980

perror_plus("close");

1981

}

1982

}

1983

#ifdef __linux__

1984

if(restore_loglevel){

1985

/* Restores kernel loglevel to default */

1986

ret = klogctl(7, NULL, 0);

1987

if(ret == -1){

1988

perror_plus("klogctl");

1989

}

1990

}

1991

#endif /* __linux__ */

1992

/* Lower privileges */

1993

errno = 0;

1994

/* Lower privileges */

1995

ret = seteuid(uid);

1996

if(ret == -1){

1997

perror_plus("seteuid");

2181

1998

}

2182

1999

}

2183

2000

2224

2041

/* Connect directly, do not use Zeroconf */

2225

2042

/* (Mainly meant for debugging) */

2226

2043

char *address = strrchr(connect_to, ':');

2227

2228

2044

if(address == NULL){

2229

2045

fprintf_plus(stderr, "No colon in address\n");

2230

2046

exitcode = EX_USAGE;

2235

2051

goto end;

2236

2052

}

2237

2053

2238

in_port_t port;

2054

uint16_t port;

2239

2055

errno = 0;

2240

2056

tmpmax = strtoimax(address+1, &tmp, 10);

2241

2057

if(errno != 0 or tmp == address+1 or *tmp != '\0'

2242

or tmpmax != (in_port_t)tmpmax){

2058

or tmpmax != (uint16_t)tmpmax){

2243

2059

fprintf_plus(stderr, "Bad port number\n");

2244

2060

exitcode = EX_USAGE;

2245

2061

goto end;

2249

2065

goto end;

2250

2066

}

2251

2067

2252

port = (in_port_t)tmpmax;

2068

port = (uint16_t)tmpmax;

2253

2069

*address = '\0';

2254

2070

/* Colon in address indicates IPv6 */

2255

2071

int af;

2303

2119

config.publish_domain = 0;

2304

2120

2305

2121

/* Allocate a new server */

2306

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2307

&config, NULL, NULL, &ret_errno);

2122

mc.server = avahi_server_new(avahi_simple_poll_get

2123

(mc.simple_poll), &config, NULL,

2124

NULL, &error);

2308

2125

2309

2126

/* Free the Avahi configuration data */

2310

2127

avahi_server_config_free(&config);

2313

2130

/* Check if creating the Avahi server object succeeded */

2314

2131

if(mc.server == NULL){

2315

2132

fprintf_plus(stderr, "Failed to create Avahi server: %s\n",

2316

avahi_strerror(ret_errno));

2133

avahi_strerror(error));

2317

2134

exitcode = EX_UNAVAILABLE;

2318

2135

goto end;

2319

2136

}

2343

2160

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

2344

2161

}

2345

2162

2346

ret = avahi_loop_with_timeout(simple_poll,

2163

ret = avahi_loop_with_timeout(mc.simple_poll,

2347

2164

(int)(retry_interval * 1000));

2348

2165

if(debug){

2349

2166

fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",

2363

2180

if(mc.server != NULL)

2364

2181

avahi_server_free(mc.server);

2365

2182

2366

if(simple_poll != NULL)

2367

avahi_simple_poll_free(simple_poll);

2183

if(mc.simple_poll != NULL)

2184

avahi_simple_poll_free(mc.simple_poll);

2368

2185

2369

2186

if(gnutls_initialized){

2370

2187

gnutls_certificate_free_credentials(mc.cred);

2375

2192

if(gpgme_initialized){

2376

2193

gpgme_release(mc.ctx);

2377

2194

}

2378

2195

2379

2196

/* Cleans up the circular linked list of Mandos servers the client

2380

2197

has seen */

2381

2198

if(mc.current_server != NULL){

2389

2206

2390

2207

/* Re-raise priviliges */

2391

2208

{

2392

raise_privileges();

2393

2209

errno = 0;

2210

ret = seteuid(0);

2211

if(ret == -1){

2212

perror_plus("seteuid");

2213

}

2394

2214

/* Run network hooks */

2395

run_network_hooks("stop", interfaces_hooks != NULL ?

2396

interfaces_hooks : "", delay);

2215

if(not run_network_hooks("stop", interface, delay)){

2216

goto end;

2217

}

2397

2218

2398

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

2399

{

2400

char *interface = NULL;

2401

while((interface=argz_next(interfaces_to_take_down,

2402

interfaces_to_take_down_size,

2403

interface))){

2404

ret_errno = take_down_interface(interface);

2405

if(ret_errno != 0){

2406

errno = ret_errno;

2407

perror_plus("Failed to take down interface");

2219

/* Take down the network interface */

2220

if(take_down_interface and geteuid() == 0){

2221

ret = ioctl(sd, SIOCGIFFLAGS, &network);

2222

if(ret == -1){

2223

perror_plus("ioctl SIOCGIFFLAGS");

2224

} else if(network.ifr_flags & IFF_UP){

2225

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

2226

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

2227

if(ret == -1){

2228

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2408

2229

}

2409

2230

}

2410

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

2411

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

2412

" down\n");

2231

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

2232

if(ret == -1){

2233

perror_plus("close");

2413

2234

}

2414

2235

}

2415

2416

lower_privileges_permanently();

2417

}

2418

2419

free(interfaces_to_take_down);

2420

free(interfaces_hooks);

2236

}

2237

/* Lower privileges permanently */

2238

errno = 0;

2239

ret = setuid(uid);

2240

if(ret == -1){

2241

perror_plus("setuid");

2242

}

2421

2243

2422

2244

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

2423

2245

if(tempdir_created){