/mandos/trunk : revision 596

88

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

89

WEXITSTATUS(), WTERMSIG() */

90

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

91

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

92

argz_delete(), argz_append(),

93

argz_stringify(), argz_add(),

94

argz_count() */

91

95

92

96

#ifdef __linux__

93

97

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

1121

1125

1122

1126

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

1123

1127

int ret;

1128

error_t ret_errno;

1124

1129

1125

1130

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

1126

1131

if(s < 0){

1132

ret_errno = errno;

1127

1133

perror_plus("socket");

1134

errno = ret_errno;

1128

1135

return false;

1129

1136

}

1130

1137

strcpy(ifr->ifr_name, ifname);

1131

1138

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1132

1139

if(ret == -1){

1133

1140

if(debug){

1141

ret_errno = errno;

1134

1142

perror_plus("ioctl SIOCGIFFLAGS");

1143

errno = ret_errno;

1135

1144

}

1136

1145

return false;

1137

1146

}

1206

1215

}

1207

1216

1208

1217

/*

1209

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

1210

* corresponds to an acceptable network device which is up.

1211

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

1212

*/

1213

int up_interface(const struct dirent *if_entry){

1214

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

1215

return 0;

1216

}

1217

1218

struct ifreq ifr;

1219

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

1220

if(debug){

1221

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

1222

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

1223

}

1224

return 0;

1225

}

1226

1227

/* Reject down interfaces */

1228

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

1229

if(debug){

1230

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

1231

if_entry->d_name);

1232

}

1233

return 0;

1234

}

1235

1236

/* Reject non-running interfaces */

1237

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

1238

if(debug){

1239

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

1240

if_entry->d_name);

1241

}

1242

return 0;

1243

}

1244

1245

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

1246

return 0;

1247

}

1248

return 1;

1218

* This function determines if a network interface is up.

1219

*/

1220

bool interface_is_up(const char *interface){

1221

struct ifreq ifr;

1222

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

1223

if(debug){

1224

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

1225

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

1226

}

1227

return false;

1228

}

1229

1230

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

1231

}

1232

1233

/*

1234

* This function determines if a network interface is running

1235

*/

1236

bool interface_is_running(const char *interface){

1237

struct ifreq ifr;

1238

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

1239

if(debug){

1240

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

1241

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

1242

}

1243

return false;

1244

}

1245

1246

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

1249

1247

}

1250

1248

1251

1249

int notdotentries(const struct dirent *direntry){

1393

1391

}

1394

1392

1395

1393

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

1396

int raise_privileges(void){

1397

int old_errno = errno;

1398

int ret_errno = 0;

1399

errno = 0;

1394

error_t raise_privileges(void){

1395

error_t old_errno = errno;

1396

error_t ret_errno = 0;

1400

1397

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

1398

ret_errno = errno;

1401

1399

perror_plus("seteuid");

1402

1400

}

1403

ret_errno = errno;

1404

1401

errno = old_errno;

1405

1402

return ret_errno;

1406

1403

}

1407

1404

1408

1405

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

1409

int raise_privileges_permanently(void){

1410

int old_errno = errno;

1411

int ret_errno = raise_privileges();

1406

error_t raise_privileges_permanently(void){

1407

error_t old_errno = errno;

1408

error_t ret_errno = raise_privileges();

1412

1409

if(ret_errno != 0){

1413

1410

errno = old_errno;

1414

1411

return ret_errno;

1415

1412

}

1416

errno = 0;

1417

1413

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

1414

ret_errno = errno;

1418

1415

perror_plus("seteuid");

1419

1416

}

1420

ret_errno = errno;

1421

1417

errno = old_errno;

1422

1418

return ret_errno;

1423

1419

}

1424

1420

1425

1421

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

1426

int lower_privileges(void){

1427

int old_errno = errno;

1428

int ret_errno = 0;

1429

errno = 0;

1422

error_t lower_privileges(void){

1423

error_t old_errno = errno;

1424

error_t ret_errno = 0;

1430

1425

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

1426

ret_errno = errno;

1431

1427

perror_plus("seteuid");

1432

1428

}

1433

ret_errno = errno;

1429

errno = old_errno;

1430

return ret_errno;

1431

}

1432

1433

/* Lower privileges permanently */

1434

error_t lower_privileges_permanently(void){

1435

error_t old_errno = errno;

1436

error_t ret_errno = 0;

1437

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

1438

ret_errno = errno;

1439

perror_plus("setuid");

1440

}

1434

1441

errno = old_errno;

1435

1442

return ret_errno;

1436

1443

}

1561

1568

return true;

1562

1569

}

1563

1570

1564

int bring_up_interface(const char * const interface, const float delay){

1571

error_t bring_up_interface(const char *const interface,

1572

const float delay){

1565

1573

int sd = -1;

1566

int ret;

1574

error_t old_errno = errno;

1575

error_t ret_errno = 0;

1576

int ret, ret_setflags;

1567

1577

struct ifreq network;

1568

AvahiIfIndex if_index = (AvahiIfIndex)if_nametoindex(interface);

1578

unsigned int if_index = if_nametoindex(interface);

1569

1579

if(if_index == 0){

1570

1580

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

1571

return EX_UNAVAILABLE;

1581

errno = old_errno;

1582

return ENXIO;

1572

1583

}

1573

1584

1574

1585

if(quit_now){

1586

errno = old_errno;

1575

1587

return EINTR;

1576

1588

}

1577

1589

1578

/* Re-raise priviliges */

1579

raise_privileges();

1580

1581

#ifdef __linux__

1582

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1583

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

1584

ret = klogctl(8, NULL, 5);

1585

bool restore_loglevel = true;

1586

if(ret == -1){

1587

restore_loglevel = false;

1588

perror_plus("klogctl");

1589

}

1590

#endif /* __linux__ */

1591

1592

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1593

if(sd < 0){

1594

perror_plus("socket");

1595

#ifdef __linux__

1596

if(restore_loglevel){

1597

ret = klogctl(7, NULL, 0);

1598

if(ret == -1){

1599

perror_plus("klogctl");

1600

}

1601

}

1602

#endif /* __linux__ */

1603

/* Lower privileges */

1604

lower_privileges();

1605

return EX_OSERR;

1606

;

1607

}

1608

strcpy(network.ifr_name, interface);

1609

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

1610

if(ret == -1){

1611

perror_plus("ioctl SIOCGIFFLAGS");

1612

#ifdef __linux__

1613

if(restore_loglevel){

1614

ret = klogctl(7, NULL, 0);

1615

if(ret == -1){

1616

perror_plus("klogctl");

1617

}

1618

}

1619

#endif /* __linux__ */

1620

/* Lower privileges */

1621

lower_privileges();

1622

return EX_OSERR;

1623

}

1624

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

1590

if(not interface_is_up(interface)){

1591

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

1592

ret_errno = errno;

1593

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

1594

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

1595

return ret_errno;

1596

}

1625

1597

network.ifr_flags |= IFF_UP;

1626

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

1598

1599

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1600

if(sd < 0){

1601

ret_errno = errno;

1602

perror_plus("socket");

1603

errno = old_errno;

1604

return ret_errno;

1605

}

1606

1607

if(quit_now){

1608

close(sd);

1609

errno = old_errno;

1610

return EINTR;

1611

}

1612

1613

if(debug){

1614

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

1615

interface);

1616

}

1617

1618

/* Raise priviliges */

1619

raise_privileges();

1620

1621

#ifdef __linux__

1622

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1623

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

1624

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

1625

bool restore_loglevel = true;

1626

if(ret_linux == -1){

1627

restore_loglevel = false;

1628

perror_plus("klogctl");

1629

}

1630

#endif /* __linux__ */

1631

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

1632

ret_errno = errno;

1633

#ifdef __linux__

1634

if(restore_loglevel){

1635

ret_linux = klogctl(7, NULL, 0);

1636

if(ret_linux == -1){

1637

perror_plus("klogctl");

1638

}

1639

}

1640

#endif /* __linux__ */

1641

1642

/* Lower privileges */

1643

lower_privileges();

1644

1645

/* Close the socket */

1646

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

1627

1647

if(ret == -1){

1648

perror_plus("close");

1649

}

1650

1651

if(ret_setflags == -1){

1652

errno = ret_errno;

1628

1653

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1629

#ifdef __linux__

1630

if(restore_loglevel){

1631

ret = klogctl(7, NULL, 0);

1632

if(ret == -1){

1633

perror_plus("klogctl");

1634

}

1635

}

1636

#endif /* __linux__ */

1637

/* Lower privileges */

1638

lower_privileges();

1639

return EX_OSERR;

1654

errno = old_errno;

1655

return ret_errno;

1640

1656

}

1657

} else if(debug){

1658

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

1659

interface);

1641

1660

}

1661

1642

1662

/* Sleep checking until interface is running.

1643

1663

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

1644

1664

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

1645

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

1646

if(ret == -1){

1647

perror_plus("ioctl SIOCGIFFLAGS");

1648

} else if(network.ifr_flags & IFF_RUNNING){

1665

if(interface_is_running(interface)){

1649

1666

break;

1650

1667

}

1651

1668

struct timespec sleeptime = { .tv_nsec = 250000000 };

1654

1671

perror_plus("nanosleep");

1655

1672

}

1656

1673

}

1657

/* Close the socket */

1658

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

1659

if(ret == -1){

1660

perror_plus("close");

1674

1675

errno = old_errno;

1676

return 0;

1677

}

1678

1679

error_t take_down_interface(const char *const interface){

1680

int sd = -1;

1681

error_t old_errno = errno;

1682

error_t ret_errno = 0;

1683

int ret, ret_setflags;

1684

struct ifreq network;

1685

unsigned int if_index = if_nametoindex(interface);

1686

if(if_index == 0){

1687

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

1688

errno = old_errno;

1689

return ENXIO;

1661

1690

}

1662

#ifdef __linux__

1663

if(restore_loglevel){

1664

/* Restores kernel loglevel to default */

1665

ret = klogctl(7, NULL, 0);

1691

if(interface_is_up(interface)){

1692

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

1693

ret_errno = errno;

1694

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

1695

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

1696

return ret_errno;

1697

}

1698

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

1699

1700

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1701

if(sd < 0){

1702

ret_errno = errno;

1703

perror_plus("socket");

1704

errno = old_errno;

1705

return ret_errno;

1706

}

1707

1708

if(debug){

1709

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

1710

interface);

1711

}

1712

1713

/* Raise priviliges */

1714

raise_privileges();

1715

1716

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

1717

ret_errno = errno;

1718

1719

/* Lower privileges */

1720

lower_privileges();

1721

1722

/* Close the socket */

1723

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

1666

1724

if(ret == -1){

1667

perror_plus("klogctl");

1668

}

1725

perror_plus("close");

1726

}

1727

1728

if(ret_setflags == -1){

1729

errno = ret_errno;

1730

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1731

errno = old_errno;

1732

return ret_errno;

1733

}

1734

} else if(debug){

1735

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

1736

interface);

1669

1737

}

1670

#endif /* __linux__ */

1671

/* Lower privileges */

1672

lower_privileges();

1673

return errno;

1738

1739

errno = old_errno;

1740

return 0;

1674

1741

}

1675

1742

1676

1743

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

1677

1744

AvahiSServiceBrowser *sb = NULL;

1678

int error;

1745

error_t ret_errno;

1679

1746

int ret;

1680

1747

intmax_t tmpmax;

1681

1748

char *tmp;

1682

1749

int exitcode = EXIT_SUCCESS;

1683

const char *interface = "";

1684

struct ifreq network;

1685

int sd = -1;

1686

bool take_down_interface = false;

1750

char *interfaces = NULL;

1751

size_t interfaces_size = 0;

1752

char *interfaces_to_take_down = NULL;

1753

size_t interfaces_to_take_down_size = 0;

1687

1754

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

1688

1755

bool tempdir_created = false;

1689

1756

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1690

1757

const char *seckey = PATHDIR "/" SECKEY;

1691

1758

const char *pubkey = PATHDIR "/" PUBKEY;

1759

char *interfaces_hooks = NULL;

1760

size_t interfaces_hooks_size = 0;

1692

1761

1693

1762

bool gnutls_initialized = false;

1694

1763

bool gpgme_initialized = false;

1785

1854

connect_to = arg;

1786

1855

break;

1787

1856

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

1788

interface = arg;

1857

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

1858

(int)',');

1859

if(ret_errno != 0){

1860

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

1861

}

1789

1862

break;

1790

1863

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

1791

1864

seckey = arg;

1923

1996

}

1924

1997

}

1925

1998

1999

/* Remove empty interface names */

2000

{

2001

char *interface = NULL;

2002

while((interface = argz_next(interfaces, interfaces_size,

2003

interface))){

2004

if(if_nametoindex(interface) == 0){

2005

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

2006

fprintf_plus(stderr, "Not using nonexisting interface"

2007

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

2008

}

2009

argz_delete(&interfaces, &interfaces_size, interface);

2010

interface = NULL;

2011

}

2012

}

2013

}

2014

1926

2015

/* Run network hooks */

1927

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

1928

goto end;

2016

{

2017

ret_errno = argz_append(&interfaces_hooks, &interfaces_hooks_size,

2018

interfaces, interfaces_size);

2019

if(ret_errno != 0){

2020

errno = ret_errno;

2021

perror_plus("argz_append");

2022

goto end;

2023

}

2024

argz_stringify(interfaces_hooks, interfaces_hooks_size, (int)',');

2025

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

2026

goto end;

2027

}

1929

2028

}

1930

2029

1931

2030

if(not debug){

1932

2031

avahi_set_log_function(empty_log);

1933

2032

}

1934

2033

1935

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

1936

struct dirent **direntries;

1937

/* First look for interfaces that are up */

1938

ret = scandir(sys_class_net, &direntries, up_interface,

1939

alphasort);

1940

if(ret == 0){

1941

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

1942

free(direntries);

1943

ret = scandir(sys_class_net, &direntries, good_interface,

1944

alphasort);

1945

}

1946

if(ret >= 1){

1947

/* Pick the first interface returned */

1948

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

1949

if(debug){

1950

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

1951

}

1952

if(interface == NULL){

1953

perror_plus("malloc");

1954

free(direntries);

1955

exitcode = EXIT_FAILURE;

1956

goto end;

1957

}

1958

free(direntries);

1959

} else {

1960

free(direntries);

1961

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

1962

exitcode = EXIT_FAILURE;

1963

goto end;

1964

}

1965

}

1966

1967

2034

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

1968

2035

from the signal handler */

1969

2036

/* Initialize the pseudo-RNG for Avahi */

2039

2106

}

2040

2107

}

2041

2108

2042

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

2043

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

2044

ret = bring_up_interface(interface, delay);

2045

if(ret){

2046

errno = ret;

2047

perror_plus("Failed to bring up interface");

2109

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

2110

if(interfaces == NULL){

2111

struct dirent **direntries;

2112

/* Look for any good interfaces */

2113

ret = scandir(sys_class_net, &direntries, good_interface,

2114

alphasort);

2115

if(ret >= 1){

2116

/* Add all found interfaces to interfaces list */

2117

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

2118

ret_errno = argz_add(&interfaces, &interfaces_size,

2119

direntries[i]->d_name);

2120

if(ret_errno != 0){

2121

perror_plus("argz_add");

2122

continue;

2123

}

2124

if(debug){

2125

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

2126

direntries[i]->d_name);

2127

}

2128

}

2129

free(direntries);

2130

} else {

2131

free(direntries);

2132

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

2133

exitcode = EXIT_FAILURE;

2134

goto end;

2135

}

2136

}

2137

2138

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

2139

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

2140

if(debug){

2141

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

2142

interfaces);

2143

}

2144

if_index = (AvahiIfIndex)if_nametoindex(interfaces);

2145

}

2146

2147

/* Bring up interfaces which are down */

2148

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

2149

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

2150

char *interface = NULL;

2151

while((interface = argz_next(interfaces, interfaces_size,

2152

interface))){

2153

bool interface_was_up = interface_is_up(interface);

2154

ret = bring_up_interface(interface, delay);

2155

if(not interface_was_up){

2156

if(ret != 0){

2157

errno = ret;

2158

perror_plus("Failed to bring up interface");

2159

} else {

2160

ret_errno = argz_add(&interfaces_to_take_down,

2161

&interfaces_to_take_down_size,

2162

interface);

2163

}

2164

}

2165

}

2166

free(interfaces);

2167

interfaces = NULL;

2168

interfaces_size = 0;

2169

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

2170

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

2048

2171

}

2049

2172

}

2050

2173

2172

2295

/* Allocate a new server */

2173

2296

mc.server = avahi_server_new(avahi_simple_poll_get

2174

2297

(mc.simple_poll), &config, NULL,

2175

NULL, &error);

2298

NULL, &ret_errno);

2176

2299

2177

2300

/* Free the Avahi configuration data */

2178

2301

avahi_server_config_free(&config);

2181

2304

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

2182

2305

if(mc.server == NULL){

2183

2306

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

2184

avahi_strerror(error));

2307

avahi_strerror(ret_errno));

2185

2308

exitcode = EX_UNAVAILABLE;

2186

2309

goto end;

2187

2310

}

2255

2378

}

2256

2379

}

2257

2380

2258

/* Run network hooks */

2259

run_network_hooks("stop", interface, delay);

2260

2261

2381

/* Re-raise priviliges */

2262

2382

{

2263

2383

raise_privileges();

2264

2384

2265

/* Take down the network interface */

2266

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

2267

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

2268

if(ret == -1){

2269

perror_plus("ioctl SIOCGIFFLAGS");

2270

} else if(network.ifr_flags & IFF_UP){

2271

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

2272

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

2273

if(ret == -1){

2274

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2385

/* Run network hooks */

2386

run_network_hooks("stop", interfaces_hooks, delay);

2387

2388

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

2389

{

2390

char *interface = NULL;

2391

while((interface=argz_next(interfaces_to_take_down,

2392

interfaces_to_take_down_size,

2393

interface))){

2394

ret_errno = take_down_interface(interface);

2395

if(ret_errno != 0){

2396

errno = ret_errno;

2397

perror_plus("Failed to take down interface");

2275

2398

}

2276

2399

}

2277

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

2278

if(ret == -1){

2279

perror_plus("close");

2400

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

2401

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

2402

" down\n");

2280

2403

}

2281

2404

}

2282

}

2283

/* Lower privileges permanently */

2284

errno = 0;

2285

ret = setuid(uid);

2286

if(ret == -1){

2287

perror_plus("setuid");

2288

}

2405

2406

lower_privileges_permanently();

2407

}

2408

2409

free(interfaces_to_take_down);

2410

free(interfaces_hooks);

2289

2411

2290

2412

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

2291

2413

if(tempdir_created){