/mandos/trunk : revision 601

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 */

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(),

47

strtof(), abort() */

61

*/

62

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

63

strtoimax() */

64

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

65

64

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

66

65

program_invocation_short_name */

67

66

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

88

87

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

89

88

WEXITSTATUS(), WTERMSIG() */

90

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() */

91

94

92

95

#ifdef __linux__

93

96

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

135

138

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

136

139

char *connect_to = NULL;

137

140

const char *hookdir = HOOKDIR;

141

uid_t uid = 65534;

142

gid_t gid = 65534;

138

143

139

144

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

140

145

typedef struct server{

141

146

const char *ip;

142

uint16_t port;

147

in_port_t port;

143

148

AvahiIfIndex if_index;

144

149

int af;

145

150

struct timespec last_seen;

149

154

150

155

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

151

156

typedef struct {

152

AvahiSimplePoll *simple_poll;

153

157

AvahiServer *server;

154

158

gnutls_certificate_credentials_t cred;

155

159

unsigned int dh_bits;

159

163

server *current_server;

160

164

} mandos_context;

161

165

162

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

163

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

164

.dh_bits = 1024, .priority = "SECURE256"

165

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

166

.current_server = NULL };

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 };

167

171

168

172

sig_atomic_t quit_now = 0;

169

173

int signal_received = 0;

170

174

171

175

/* Function to use when printing errors */

172

176

void perror_plus(const char *print_text){

177

int e = errno;

173

178

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

174

179

program_invocation_short_name);

180

errno = e;

175

181

perror(print_text);

176

182

}

177

183

203

209

}

204

210

205

211

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

206

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

212

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

207

213

int af){

208

214

int ret;

209

215

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

247

253

gpgme_error_t rc;

248

254

gpgme_engine_info_t engine_info;

249

255

250

251

256

/*

252

257

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

253

258

*/

463

468

}

464

469

465

470

static const char * safer_gnutls_strerror(int value){

466

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

467

-Wunreachable-code */

471

const char *ret = gnutls_strerror(value);

468

472

if(ret == NULL)

469

473

ret = "(unknown)";

470

474

return ret;

615

619

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

616

620

617

621

/* Called when a Mandos server is found */

618

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

622

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

619

623

AvahiIfIndex if_index,

620

624

int af){

621

625

int ret, tcp_sd = -1;

660

664

661

665

if(debug){

662

666

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

663

PRIu16 "\n", ip, port);

667

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

664

668

}

665

669

666

670

tcp_sd = socket(pf, SOCK_STREAM, 0);

697

701

goto mandos_end;

698

702

}

699

703

if(af == AF_INET6){

700

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

701

-Wconversion and

702

-Wunreachable-code */

703

704

to.in6.sin6_port = htons(port);

704

705

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

705

706

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

706

707

-Wunreachable-code*/

730

731

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

731

732

perror_plus("if_indextoname");

732

733

} else {

733

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

734

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

734

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

735

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

735

736

}

736

737

} else {

737

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

738

ip, port);

738

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

739

ip, (uintmax_t)port);

739

740

}

740

741

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

741

742

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

819

820

goto mandos_end;

820

821

}

821

822

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

823

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

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);

824

828

825

829

if(quit_now){

826

830

errno = EINTR;

999

1003

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1000

1004

flags,

1001

1005

AVAHI_GCC_UNUSED void* userdata){

1002

assert(r);

1006

if(r == NULL){

1007

return;

1008

}

1003

1009

1004

1010

/* Called whenever a service has been resolved successfully or

1005

1011

timed out */

1026

1032

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

1027

1033

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

1028

1034

}

1029

int ret = start_mandos_communication(ip, port, interface,

1035

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

1036

interface,

1030

1037

avahi_proto_to_af(proto));

1031

1038

if(ret == 0){

1032

avahi_simple_poll_quit(mc.simple_poll);

1039

avahi_simple_poll_quit(simple_poll);

1033

1040

} else {

1034

if(not add_server(ip, port, interface,

1041

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

1035

1042

avahi_proto_to_af(proto))){

1036

1043

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

1037

1044

" list\n", name);

1052

1059

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1053

1060

flags,

1054

1061

AVAHI_GCC_UNUSED void* userdata){

1055

assert(b);

1062

if(b == NULL){

1063

return;

1064

}

1056

1065

1057

1066

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

1058

1067

is removed from the LAN */

1067

1076

1068

1077

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

1069

1078

avahi_strerror(avahi_server_errno(mc.server)));

1070

avahi_simple_poll_quit(mc.simple_poll);

1079

avahi_simple_poll_quit(simple_poll);

1071

1080

return;

1072

1081

1073

1082

case AVAHI_BROWSER_NEW:

1106

1115

signal_received = sig;

1107

1116

int old_errno = errno;

1108

1117

/* set main loop to exit */

1109

if(mc.simple_poll != NULL){

1110

avahi_simple_poll_quit(mc.simple_poll);

1118

if(simple_poll != NULL){

1119

avahi_simple_poll_quit(simple_poll);

1111

1120

}

1112

1121

errno = old_errno;

1113

1122

}

1114

1123

1115

1124

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

1116

1125

int ret;

1126

error_t ret_errno;

1117

1127

1118

1128

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

1119

1129

if(s < 0){

1130

ret_errno = errno;

1120

1131

perror_plus("socket");

1132

errno = ret_errno;

1121

1133

return false;

1122

1134

}

1123

1135

strcpy(ifr->ifr_name, ifname);

1124

1136

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1125

1137

if(ret == -1){

1126

1138

if(debug){

1139

ret_errno = errno;

1127

1140

perror_plus("ioctl SIOCGIFFLAGS");

1141

errno = ret_errno;

1128

1142

}

1129

1143

return false;

1130

1144

}

1199

1213

}

1200

1214

1201

1215

/*

1202

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

1203

* corresponds to an acceptable network device which is up.

1204

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

1205

*/

1206

int up_interface(const struct dirent *if_entry){

1207

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

1208

return 0;

1209

}

1210

1211

struct ifreq ifr;

1212

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

1213

if(debug){

1214

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

1215

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

1216

}

1217

return 0;

1218

}

1219

1220

/* Reject down interfaces */

1221

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

1222

if(debug){

1223

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

1224

if_entry->d_name);

1225

}

1226

return 0;

1227

}

1228

1229

/* Reject non-running interfaces */

1230

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

1231

if(debug){

1232

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

1233

if_entry->d_name);

1234

}

1235

return 0;

1236

}

1237

1238

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

1239

return 0;

1240

}

1241

return 1;

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);

1242

1245

}

1243

1246

1244

1247

int notdotentries(const struct dirent *direntry){

1361

1364

mc.current_server->if_index,

1362

1365

mc.current_server->af);

1363

1366

if(ret == 0){

1364

avahi_simple_poll_quit(mc.simple_poll);

1367

avahi_simple_poll_quit(simple_poll);

1365

1368

return 0;

1366

1369

}

1367

1370

ret = clock_gettime(CLOCK_MONOTONIC,

1385

1388

}

1386

1389

}

1387

1390

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

1388

1443

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

1389

1444

const float delay){

1390

1445

struct dirent **direntries;

1393

1448

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

1394

1449

alphasort);

1395

1450

if(numhooks == -1){

1396

perror_plus("scandir");

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

}

1397

1459

} else {

1398

1460

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

1399

1461

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

1412

1474

if(hook_pid == 0){

1413

1475

/* Child */

1414

1476

/* Raise privileges */

1415

errno = 0;

1416

ret = seteuid(0);

1417

if(ret == -1){

1418

perror_plus("seteuid");

1419

}

1420

/* Raise privileges even more */

1421

errno = 0;

1422

ret = setuid(0);

1423

if(ret == -1){

1424

perror_plus("setuid");

1425

}

1477

raise_privileges_permanently();

1426

1478

/* Set group */

1427

1479

errno = 0;

1428

1480

ret = setgid(0);

1448

1500

perror_plus("setenv");

1449

1501

_exit(EX_OSERR);

1450

1502

}

1451

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

1503

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

1452

1504

if(ret == -1){

1453

1505

perror_plus("setenv");

1454

1506

_exit(EX_OSERR);

1471

1523

_exit(EX_OSERR);

1472

1524

}

1473

1525

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

}

1474

1533

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

1475

1534

perror_plus("execl");

1476

1535

_exit(EXIT_FAILURE);

1514

1573

return true;

1515

1574

}

1516

1575

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

1517

1748

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

1518

1749

AvahiSServiceBrowser *sb = NULL;

1519

int error;

1750

error_t ret_errno;

1520

1751

int ret;

1521

1752

intmax_t tmpmax;

1522

1753

char *tmp;

1523

1754

int exitcode = EXIT_SUCCESS;

1524

const char *interface = "";

1525

struct ifreq network;

1526

int sd = -1;

1527

bool take_down_interface = false;

1528

uid_t uid;

1529

gid_t gid;

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;

1530

1759

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

1531

1760

bool tempdir_created = false;

1532

1761

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1533

1762

const char *seckey = PATHDIR "/" SECKEY;

1534

1763

const char *pubkey = PATHDIR "/" PUBKEY;

1764

char *interfaces_hooks = NULL;

1765

size_t interfaces_hooks_size = 0;

1535

1766

1536

1767

bool gnutls_initialized = false;

1537

1768

bool gpgme_initialized = false;

1599

1830

.group = 2 },

1600

1831

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

1601

1832

.arg = "SECONDS",

1602

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

1833

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

1603

1834

.group = 2 },

1604

1835

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

1605

1836

.arg = "DIR",

1628

1859

connect_to = arg;

1629

1860

break;

1630

1861

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

1631

interface = arg;

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

}

1632

1867

break;

1633

1868

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

1634

1869

seckey = arg;

1712

1947

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

1713

1948

1714

1949

/* Re-raise priviliges */

1715

errno = 0;

1716

ret = seteuid(0);

1717

if(ret == -1){

1718

perror_plus("seteuid");

1719

} else {

1950

if(raise_privileges() == 0){

1720

1951

struct stat st;

1721

1952

1722

1953

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

1770

2001

}

1771

2002

}

1772

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

}

2017

}

2018

}

2019

1773

2020

/* Run network hooks */

1774

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

1775

goto end;

2021

{

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)',');

2033

}

2034

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

2035

interfaces_hooks : "", delay)){

2036

goto end;

2037

}

1776

2038

}

1777

2039

1778

2040

if(not debug){

1779

2041

avahi_set_log_function(empty_log);

1780

2042

}

1781

2043

1782

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

1783

struct dirent **direntries;

1784

/* First look for interfaces that are up */

1785

ret = scandir(sys_class_net, &direntries, up_interface,

1786

alphasort);

1787

if(ret == 0){

1788

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

1789

free(direntries);

1790

ret = scandir(sys_class_net, &direntries, good_interface,

1791

alphasort);

1792

}

1793

if(ret >= 1){

1794

/* Pick the first interface returned */

1795

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

1796

if(debug){

1797

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

1798

}

1799

if(interface == NULL){

1800

perror_plus("malloc");

1801

free(direntries);

1802

exitcode = EXIT_FAILURE;

1803

goto end;

1804

}

1805

free(direntries);

1806

} else {

1807

free(direntries);

1808

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

1809

exitcode = EXIT_FAILURE;

1810

goto end;

1811

}

1812

}

1813

1814

2044

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

1815

2045

from the signal handler */

1816

2046

/* Initialize the pseudo-RNG for Avahi */

1817

2047

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

1818

mc.simple_poll = avahi_simple_poll_new();

1819

if(mc.simple_poll == NULL){

2048

simple_poll = avahi_simple_poll_new();

2049

if(simple_poll == NULL){

1820

2050

fprintf_plus(stderr,

1821

2051

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

1822

2052

exitcode = EX_UNAVAILABLE;

1886

2116

}

1887

2117

}

1888

2118

1889

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

1890

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

1891

if_index = (AvahiIfIndex) if_nametoindex(interface);

1892

if(if_index == 0){

1893

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

1894

exitcode = EX_UNAVAILABLE;

1895

goto end;

1896

}

1897

1898

if(quit_now){

1899

goto end;

1900

}

1901

1902

/* Re-raise priviliges */

1903

errno = 0;

1904

ret = seteuid(0);

1905

if(ret == -1){

1906

perror_plus("seteuid");

1907

}

1908

1909

#ifdef __linux__

1910

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1911

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

1912

ret = klogctl(8, NULL, 5);

1913

bool restore_loglevel = true;

1914

if(ret == -1){

1915

restore_loglevel = false;

1916

perror_plus("klogctl");

1917

}

1918

#endif /* __linux__ */

1919

1920

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1921

if(sd < 0){

1922

perror_plus("socket");

1923

exitcode = EX_OSERR;

1924

#ifdef __linux__

1925

if(restore_loglevel){

1926

ret = klogctl(7, NULL, 0);

1927

if(ret == -1){

1928

perror_plus("klogctl");

1929

}

1930

}

1931

#endif /* __linux__ */

1932

/* Lower privileges */

1933

errno = 0;

1934

ret = seteuid(uid);

1935

if(ret == -1){

1936

perror_plus("seteuid");

1937

}

1938

goto end;

1939

}

1940

strcpy(network.ifr_name, interface);

1941

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

1942

if(ret == -1){

1943

perror_plus("ioctl SIOCGIFFLAGS");

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

exitcode = EX_OSERR;

1953

/* Lower privileges */

1954

errno = 0;

1955

ret = seteuid(uid);

1956

if(ret == -1){

1957

perror_plus("seteuid");

1958

}

1959

goto end;

1960

}

1961

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

1962

network.ifr_flags |= IFF_UP;

1963

take_down_interface = true;

1964

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

1965

if(ret == -1){

1966

take_down_interface = false;

1967

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1968

exitcode = EX_OSERR;

1969

#ifdef __linux__

1970

if(restore_loglevel){

1971

ret = klogctl(7, NULL, 0);

1972

if(ret == -1){

1973

perror_plus("klogctl");

1974

}

1975

}

1976

#endif /* __linux__ */

1977

/* Lower privileges */

1978

errno = 0;

1979

ret = seteuid(uid);

1980

if(ret == -1){

1981

perror_plus("seteuid");

1982

}

1983

goto end;

1984

}

1985

}

1986

/* Sleep checking until interface is running.

1987

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

1988

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

1989

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

1990

if(ret == -1){

1991

perror_plus("ioctl SIOCGIFFLAGS");

1992

} else if(network.ifr_flags & IFF_RUNNING){

1993

break;

1994

}

1995

struct timespec sleeptime = { .tv_nsec = 250000000 };

1996

ret = nanosleep(&sleeptime, NULL);

1997

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

1998

perror_plus("nanosleep");

1999

}

2000

}

2001

if(not take_down_interface){

2002

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

2003

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

2004

if(ret == -1){

2005

perror_plus("close");

2006

}

2007

}

2008

#ifdef __linux__

2009

if(restore_loglevel){

2010

/* Restores kernel loglevel to default */

2011

ret = klogctl(7, NULL, 0);

2012

if(ret == -1){

2013

perror_plus("klogctl");

2014

}

2015

}

2016

#endif /* __linux__ */

2017

/* Lower privileges */

2018

errno = 0;

2019

/* Lower privileges */

2020

ret = seteuid(uid);

2021

if(ret == -1){

2022

perror_plus("seteuid");

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");

2023

2181

}

2024

2182

}

2025

2183

2066

2224

/* Connect directly, do not use Zeroconf */

2067

2225

/* (Mainly meant for debugging) */

2068

2226

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

2227

2069

2228

if(address == NULL){

2070

2229

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

2071

2230

exitcode = EX_USAGE;

2076

2235

goto end;

2077

2236

}

2078

2237

2079

uint16_t port;

2238

in_port_t port;

2080

2239

errno = 0;

2081

2240

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

2082

2241

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

2083

or tmpmax != (uint16_t)tmpmax){

2242

or tmpmax != (in_port_t)tmpmax){

2084

2243

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

2085

2244

exitcode = EX_USAGE;

2086

2245

goto end;

2090

2249

goto end;

2091

2250

}

2092

2251

2093

port = (uint16_t)tmpmax;

2252

port = (in_port_t)tmpmax;

2094

2253

*address = '\0';

2095

2254

/* Colon in address indicates IPv6 */

2096

2255

int af;

2144

2303

config.publish_domain = 0;

2145

2304

2146

2305

/* Allocate a new server */

2147

mc.server = avahi_server_new(avahi_simple_poll_get

2148

(mc.simple_poll), &config, NULL,

2149

NULL, &error);

2306

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2307

&config, NULL, NULL, &ret_errno);

2150

2308

2151

2309

/* Free the Avahi configuration data */

2152

2310

avahi_server_config_free(&config);

2155

2313

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

2156

2314

if(mc.server == NULL){

2157

2315

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

2158

avahi_strerror(error));

2316

avahi_strerror(ret_errno));

2159

2317

exitcode = EX_UNAVAILABLE;

2160

2318

goto end;

2161

2319

}

2185

2343

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

2186

2344

}

2187

2345

2188

ret = avahi_loop_with_timeout(mc.simple_poll,

2346

ret = avahi_loop_with_timeout(simple_poll,

2189

2347

(int)(retry_interval * 1000));

2190

2348

if(debug){

2191

2349

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

2205

2363

if(mc.server != NULL)

2206

2364

avahi_server_free(mc.server);

2207

2365

2208

if(mc.simple_poll != NULL)

2209

avahi_simple_poll_free(mc.simple_poll);

2366

if(simple_poll != NULL)

2367

avahi_simple_poll_free(simple_poll);

2210

2368

2211

2369

if(gnutls_initialized){

2212

2370

gnutls_certificate_free_credentials(mc.cred);

2229

2387

}

2230

2388

}

2231

2389

2232

/* Run network hooks */

2233

run_network_hooks("stop", interface, delay);

2234

2235

2390

/* Re-raise priviliges */

2236

2391

{

2237

errno = 0;

2238

ret = seteuid(0);

2239

if(ret == -1){

2240

perror_plus("seteuid");

2241

}

2242

2243

/* Take down the network interface */

2244

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

2245

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

2246

if(ret == -1){

2247

perror_plus("ioctl SIOCGIFFLAGS");

2248

} else if(network.ifr_flags & IFF_UP){

2249

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

2250

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

2251

if(ret == -1){

2252

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2392

raise_privileges();

2393

2394

/* Run network hooks */

2395

run_network_hooks("stop", interfaces_hooks != NULL ?

2396

interfaces_hooks : "", delay);

2397

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");

2253

2408

}

2254

2409

}

2255

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

2256

if(ret == -1){

2257

perror_plus("close");

2410

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

2411

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

2412

" down\n");

2258

2413

}

2259

2414

}

2260

}

2261

/* Lower privileges permanently */

2262

errno = 0;

2263

ret = setuid(uid);

2264

if(ret == -1){

2265

perror_plus("setuid");

2266

}

2415

2416

lower_privileges_permanently();

2417

}

2418

2419

free(interfaces_to_take_down);

2420

free(interfaces_hooks);

2267

2421

2268

2422

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

2269

2423

if(tempdir_created){