/mandos/trunk : revision 600

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;

205

210

}

206

211

207

212

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

208

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

213

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

209

214

int af){

210

215

int ret;

211

216

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

465

470

}

466

471

467

472

static const char * safer_gnutls_strerror(int value){

468

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

469

-Wunreachable-code */

473

const char *ret = gnutls_strerror(value);

470

474

if(ret == NULL)

471

475

ret = "(unknown)";

472

476

return ret;

617

621

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

618

622

619

623

/* Called when a Mandos server is found */

620

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

624

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

621

625

AvahiIfIndex if_index,

622

626

int af){

623

627

int ret, tcp_sd = -1;

662

666

663

667

if(debug){

664

668

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

665

PRIu16 "\n", ip, port);

669

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

666

670

}

667

671

668

672

tcp_sd = socket(pf, SOCK_STREAM, 0);

699

703

goto mandos_end;

700

704

}

701

705

if(af == AF_INET6){

702

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

703

-Wconversion and

704

-Wunreachable-code */

705

706

to.in6.sin6_port = htons(port);

706

707

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

707

708

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

708

709

-Wunreachable-code*/

732

733

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

733

734

perror_plus("if_indextoname");

734

735

} else {

735

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

736

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

736

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

737

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

737

738

}

738

739

} else {

739

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

740

ip, port);

740

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

741

ip, (uintmax_t)port);

741

742

}

742

743

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

743

744

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

821

822

goto mandos_end;

822

823

}

823

824

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

825

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

825

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

826

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

827

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

828

gnutls_transport_set_ptr(session,

829

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

826

830

827

831

if(quit_now){

828

832

errno = EINTR;

1001

1005

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1002

1006

flags,

1003

1007

AVAHI_GCC_UNUSED void* userdata){

1004

assert(r);

1008

if(r == NULL){

1009

return;

1010

}

1005

1011

1006

1012

/* Called whenever a service has been resolved successfully or

1007

1013

timed out */

1028

1034

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

1029

1035

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

1030

1036

}

1031

int ret = start_mandos_communication(ip, port, interface,

1037

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

1038

interface,

1032

1039

avahi_proto_to_af(proto));

1033

1040

if(ret == 0){

1034

1041

avahi_simple_poll_quit(mc.simple_poll);

1035

1042

} else {

1036

if(not add_server(ip, port, interface,

1043

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

1037

1044

avahi_proto_to_af(proto))){

1038

1045

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

1039

1046

" list\n", name);

1054

1061

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1055

1062

flags,

1056

1063

AVAHI_GCC_UNUSED void* userdata){

1057

assert(b);

1064

if(b == NULL){

1065

return;

1066

}

1058

1067

1059

1068

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

1060

1069

is removed from the LAN */

1116

1125

1117

1126

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

1118

1127

int ret;

1128

error_t ret_errno;

1119

1129

1120

1130

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

1121

1131

if(s < 0){

1132

ret_errno = errno;

1122

1133

perror_plus("socket");

1134

errno = ret_errno;

1123

1135

return false;

1124

1136

}

1125

1137

strcpy(ifr->ifr_name, ifname);

1126

1138

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1127

1139

if(ret == -1){

1128

1140

if(debug){

1141

ret_errno = errno;

1129

1142

perror_plus("ioctl SIOCGIFFLAGS");

1143

errno = ret_errno;

1130

1144

}

1131

1145

return false;

1132

1146

}

1201

1215

}

1202

1216

1203

1217

/*

1204

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

1205

* corresponds to an acceptable network device which is up.

1206

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

1207

*/

1208

int up_interface(const struct dirent *if_entry){

1209

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

1210

return 0;

1211

}

1212

1213

struct ifreq ifr;

1214

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

1215

if(debug){

1216

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

1217

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

1218

}

1219

return 0;

1220

}

1221

1222

/* Reject down interfaces */

1223

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

1224

if(debug){

1225

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

1226

if_entry->d_name);

1227

}

1228

return 0;

1229

}

1230

1231

/* Reject non-running interfaces */

1232

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

1233

if(debug){

1234

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

1235

if_entry->d_name);

1236

}

1237

return 0;

1238

}

1239

1240

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

1241

return 0;

1242

}

1243

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);

1244

1247

}

1245

1248

1246

1249

int notdotentries(const struct dirent *direntry){

1387

1390

}

1388

1391

}

1389

1392

1393

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

1394

error_t raise_privileges(void){

1395

error_t old_errno = errno;

1396

error_t ret_errno = 0;

1397

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

1398

ret_errno = errno;

1399

perror_plus("seteuid");

1400

}

1401

errno = old_errno;

1402

return ret_errno;

1403

}

1404

1405

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

1406

error_t raise_privileges_permanently(void){

1407

error_t old_errno = errno;

1408

error_t ret_errno = raise_privileges();

1409

if(ret_errno != 0){

1410

errno = old_errno;

1411

return ret_errno;

1412

}

1413

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

1414

ret_errno = errno;

1415

perror_plus("seteuid");

1416

}

1417

errno = old_errno;

1418

return ret_errno;

1419

}

1420

1421

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

1422

error_t lower_privileges(void){

1423

error_t old_errno = errno;

1424

error_t ret_errno = 0;

1425

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

1426

ret_errno = errno;

1427

perror_plus("seteuid");

1428

}

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

}

1441

errno = old_errno;

1442

return ret_errno;

1443

}

1444

1390

1445

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

1391

1446

const float delay){

1392

1447

struct dirent **direntries;

1395

1450

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

1396

1451

alphasort);

1397

1452

if(numhooks == -1){

1398

perror_plus("scandir");

1453

if(errno == ENOENT){

1454

if(debug){

1455

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

1456

" found\n", hookdir);

1457

}

1458

} else {

1459

perror_plus("scandir");

1460

}

1399

1461

} else {

1400

1462

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

1401

1463

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

1414

1476

if(hook_pid == 0){

1415

1477

/* Child */

1416

1478

/* Raise privileges */

1417

errno = 0;

1418

ret = seteuid(0);

1419

if(ret == -1){

1420

perror_plus("seteuid");

1421

}

1422

/* Raise privileges even more */

1423

errno = 0;

1424

ret = setuid(0);

1425

if(ret == -1){

1426

perror_plus("setuid");

1427

}

1479

raise_privileges_permanently();

1428

1480

/* Set group */

1429

1481

errno = 0;

1430

1482

ret = setgid(0);

1523

1575

return true;

1524

1576

}

1525

1577

1578

error_t bring_up_interface(const char *const interface,

1579

const float delay){

1580

int sd = -1;

1581

error_t old_errno = errno;

1582

error_t ret_errno = 0;

1583

int ret, ret_setflags;

1584

struct ifreq network;

1585

unsigned int if_index = if_nametoindex(interface);

1586

if(if_index == 0){

1587

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

1588

errno = old_errno;

1589

return ENXIO;

1590

}

1591

1592

if(quit_now){

1593

errno = old_errno;

1594

return EINTR;

1595

}

1596

1597

if(not interface_is_up(interface)){

1598

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

1599

ret_errno = errno;

1600

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

1601

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

1602

return ret_errno;

1603

}

1604

network.ifr_flags |= IFF_UP;

1605

1606

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1607

if(sd < 0){

1608

ret_errno = errno;

1609

perror_plus("socket");

1610

errno = old_errno;

1611

return ret_errno;

1612

}

1613

1614

if(quit_now){

1615

close(sd);

1616

errno = old_errno;

1617

return EINTR;

1618

}

1619

1620

if(debug){

1621

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

1622

interface);

1623

}

1624

1625

/* Raise priviliges */

1626

raise_privileges();

1627

1628

#ifdef __linux__

1629

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1630

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

1631

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

1632

bool restore_loglevel = true;

1633

if(ret_linux == -1){

1634

restore_loglevel = false;

1635

perror_plus("klogctl");

1636

}

1637

#endif /* __linux__ */

1638

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

1639

ret_errno = errno;

1640

#ifdef __linux__

1641

if(restore_loglevel){

1642

ret_linux = klogctl(7, NULL, 0);

1643

if(ret_linux == -1){

1644

perror_plus("klogctl");

1645

}

1646

}

1647

#endif /* __linux__ */

1648

1649

/* Lower privileges */

1650

lower_privileges();

1651

1652

/* Close the socket */

1653

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

1654

if(ret == -1){

1655

perror_plus("close");

1656

}

1657

1658

if(ret_setflags == -1){

1659

errno = ret_errno;

1660

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1661

errno = old_errno;

1662

return ret_errno;

1663

}

1664

} else if(debug){

1665

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

1666

interface);

1667

}

1668

1669

/* Sleep checking until interface is running.

1670

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

1671

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

1672

if(interface_is_running(interface)){

1673

break;

1674

}

1675

struct timespec sleeptime = { .tv_nsec = 250000000 };

1676

ret = nanosleep(&sleeptime, NULL);

1677

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

1678

perror_plus("nanosleep");

1679

}

1680

}

1681

1682

errno = old_errno;

1683

return 0;

1684

}

1685

1686

error_t take_down_interface(const char *const interface){

1687

int sd = -1;

1688

error_t old_errno = errno;

1689

error_t ret_errno = 0;

1690

int ret, ret_setflags;

1691

struct ifreq network;

1692

unsigned int if_index = if_nametoindex(interface);

1693

if(if_index == 0){

1694

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

1695

errno = old_errno;

1696

return ENXIO;

1697

}

1698

if(interface_is_up(interface)){

1699

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

1700

ret_errno = errno;

1701

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

1702

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

1703

return ret_errno;

1704

}

1705

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

1706

1707

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1708

if(sd < 0){

1709

ret_errno = errno;

1710

perror_plus("socket");

1711

errno = old_errno;

1712

return ret_errno;

1713

}

1714

1715

if(debug){

1716

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

1717

interface);

1718

}

1719

1720

/* Raise priviliges */

1721

raise_privileges();

1722

1723

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

1724

ret_errno = errno;

1725

1726

/* Lower privileges */

1727

lower_privileges();

1728

1729

/* Close the socket */

1730

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

1731

if(ret == -1){

1732

perror_plus("close");

1733

}

1734

1735

if(ret_setflags == -1){

1736

errno = ret_errno;

1737

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1738

errno = old_errno;

1739

return ret_errno;

1740

}

1741

} else if(debug){

1742

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

1743

interface);

1744

}

1745

1746

errno = old_errno;

1747

return 0;

1748

}

1749

1526

1750

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

1527

1751

AvahiSServiceBrowser *sb = NULL;

1528

int error;

1752

error_t ret_errno;

1529

1753

int ret;

1530

1754

intmax_t tmpmax;

1531

1755

char *tmp;

1532

1756

int exitcode = EXIT_SUCCESS;

1533

const char *interface = "";

1534

struct ifreq network;

1535

int sd = -1;

1536

bool take_down_interface = false;

1537

uid_t uid;

1538

gid_t gid;

1757

char *interfaces = NULL;

1758

size_t interfaces_size = 0;

1759

char *interfaces_to_take_down = NULL;

1760

size_t interfaces_to_take_down_size = 0;

1539

1761

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

1540

1762

bool tempdir_created = false;

1541

1763

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1542

1764

const char *seckey = PATHDIR "/" SECKEY;

1543

1765

const char *pubkey = PATHDIR "/" PUBKEY;

1766

char *interfaces_hooks = NULL;

1767

size_t interfaces_hooks_size = 0;

1544

1768

1545

1769

bool gnutls_initialized = false;

1546

1770

bool gpgme_initialized = false;

1637

1861

connect_to = arg;

1638

1862

break;

1639

1863

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

1640

interface = arg;

1864

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

1865

(int)',');

1866

if(ret_errno != 0){

1867

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

1868

}

1641

1869

break;

1642

1870

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

1643

1871

seckey = arg;

1721

1949

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

1722

1950

1723

1951

/* Re-raise priviliges */

1724

errno = 0;

1725

ret = seteuid(0);

1726

if(ret == -1){

1727

perror_plus("seteuid");

1728

} else {

1952

if(raise_privileges() == 0){

1729

1953

struct stat st;

1730

1954

1731

1955

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

1779

2003

}

1780

2004

}

1781

2005

2006

/* Remove empty interface names */

2007

{

2008

char *interface = NULL;

2009

while((interface = argz_next(interfaces, interfaces_size,

2010

interface))){

2011

if(if_nametoindex(interface) == 0){

2012

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

2013

fprintf_plus(stderr, "Not using nonexisting interface"

2014

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

2015

}

2016

argz_delete(&interfaces, &interfaces_size, interface);

2017

interface = NULL;

2018

}

2019

}

2020

}

2021

1782

2022

/* Run network hooks */

1783

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

1784

goto end;

2023

{

2024

2025

if(interfaces != NULL){

2026

interfaces_hooks = malloc(interfaces_size);

2027

if(interfaces_hooks == NULL){

2028

perror_plus("malloc");

2029

goto end;

2030

}

2031

memcpy(interfaces_hooks, interfaces, interfaces_size);

2032

interfaces_hooks_size = interfaces_size;

2033

argz_stringify(interfaces_hooks, interfaces_hooks_size,

2034

(int)',');

2035

}

2036

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

2037

interfaces_hooks : "", delay)){

2038

goto end;

2039

}

1785

2040

}

1786

2041

1787

2042

if(not debug){

1788

2043

avahi_set_log_function(empty_log);

1789

2044

}

1790

2045

1791

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

1792

struct dirent **direntries;

1793

/* First look for interfaces that are up */

1794

ret = scandir(sys_class_net, &direntries, up_interface,

1795

alphasort);

1796

if(ret == 0){

1797

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

1798

free(direntries);

1799

ret = scandir(sys_class_net, &direntries, good_interface,

1800

alphasort);

1801

}

1802

if(ret >= 1){

1803

/* Pick the first interface returned */

1804

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

1805

if(debug){

1806

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

1807

}

1808

if(interface == NULL){

1809

perror_plus("malloc");

1810

free(direntries);

1811

exitcode = EXIT_FAILURE;

1812

goto end;

1813

}

1814

free(direntries);

1815

} else {

1816

free(direntries);

1817

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

1818

exitcode = EXIT_FAILURE;

1819

goto end;

1820

}

1821

}

1822

1823

2046

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

1824

2047

from the signal handler */

1825

2048

/* Initialize the pseudo-RNG for Avahi */

1895

2118

}

1896

2119

}

1897

2120

1898

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

1899

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

1900

if_index = (AvahiIfIndex) if_nametoindex(interface);

1901

if(if_index == 0){

1902

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

1903

exitcode = EX_UNAVAILABLE;

1904

goto end;

1905

}

1906

1907

if(quit_now){

1908

goto end;

1909

}

1910

1911

/* Re-raise priviliges */

1912

errno = 0;

1913

ret = seteuid(0);

1914

if(ret == -1){

1915

perror_plus("seteuid");

1916

}

1917

1918

#ifdef __linux__

1919

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1920

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

1921

ret = klogctl(8, NULL, 5);

1922

bool restore_loglevel = true;

1923

if(ret == -1){

1924

restore_loglevel = false;

1925

perror_plus("klogctl");

1926

}

1927

#endif /* __linux__ */

1928

1929

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1930

if(sd < 0){

1931

perror_plus("socket");

1932

exitcode = EX_OSERR;

1933

#ifdef __linux__

1934

if(restore_loglevel){

1935

ret = klogctl(7, NULL, 0);

1936

if(ret == -1){

1937

perror_plus("klogctl");

1938

}

1939

}

1940

#endif /* __linux__ */

1941

/* Lower privileges */

1942

errno = 0;

1943

ret = seteuid(uid);

1944

if(ret == -1){

1945

perror_plus("seteuid");

1946

}

1947

goto end;

1948

}

1949

strcpy(network.ifr_name, interface);

1950

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

1951

if(ret == -1){

1952

perror_plus("ioctl SIOCGIFFLAGS");

1953

#ifdef __linux__

1954

if(restore_loglevel){

1955

ret = klogctl(7, NULL, 0);

1956

if(ret == -1){

1957

perror_plus("klogctl");

1958

}

1959

}

1960

#endif /* __linux__ */

1961

exitcode = EX_OSERR;

1962

/* Lower privileges */

1963

errno = 0;

1964

ret = seteuid(uid);

1965

if(ret == -1){

1966

perror_plus("seteuid");

1967

}

1968

goto end;

1969

}

1970

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

1971

network.ifr_flags |= IFF_UP;

1972

take_down_interface = true;

1973

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

1974

if(ret == -1){

1975

take_down_interface = false;

1976

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1977

exitcode = EX_OSERR;

1978

#ifdef __linux__

1979

if(restore_loglevel){

1980

ret = klogctl(7, NULL, 0);

1981

if(ret == -1){

1982

perror_plus("klogctl");

1983

}

1984

}

1985

#endif /* __linux__ */

1986

/* Lower privileges */

1987

errno = 0;

1988

ret = seteuid(uid);

1989

if(ret == -1){

1990

perror_plus("seteuid");

1991

}

1992

goto end;

1993

}

1994

}

1995

/* Sleep checking until interface is running.

1996

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

1997

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

1998

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

1999

if(ret == -1){

2000

perror_plus("ioctl SIOCGIFFLAGS");

2001

} else if(network.ifr_flags & IFF_RUNNING){

2002

break;

2003

}

2004

struct timespec sleeptime = { .tv_nsec = 250000000 };

2005

ret = nanosleep(&sleeptime, NULL);

2006

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

2007

perror_plus("nanosleep");

2008

}

2009

}

2010

if(not take_down_interface){

2011

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

2012

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

2013

if(ret == -1){

2014

perror_plus("close");

2015

}

2016

}

2017

#ifdef __linux__

2018

if(restore_loglevel){

2019

/* Restores kernel loglevel to default */

2020

ret = klogctl(7, NULL, 0);

2021

if(ret == -1){

2022

perror_plus("klogctl");

2023

}

2024

}

2025

#endif /* __linux__ */

2026

/* Lower privileges */

2027

errno = 0;

2028

/* Lower privileges */

2029

ret = seteuid(uid);

2030

if(ret == -1){

2031

perror_plus("seteuid");

2121

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

2122

if(interfaces == NULL){

2123

struct dirent **direntries;

2124

/* Look for any good interfaces */

2125

ret = scandir(sys_class_net, &direntries, good_interface,

2126

alphasort);

2127

if(ret >= 1){

2128

/* Add all found interfaces to interfaces list */

2129

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

2130

ret_errno = argz_add(&interfaces, &interfaces_size,

2131

direntries[i]->d_name);

2132

if(ret_errno != 0){

2133

perror_plus("argz_add");

2134

continue;

2135

}

2136

if(debug){

2137

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

2138

direntries[i]->d_name);

2139

}

2140

}

2141

free(direntries);

2142

} else {

2143

free(direntries);

2144

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

2145

exitcode = EXIT_FAILURE;

2146

goto end;

2147

}

2148

}

2149

2150

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

2151

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

2152

if(debug){

2153

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

2154

interfaces);

2155

}

2156

if_index = (AvahiIfIndex)if_nametoindex(interfaces);

2157

}

2158

2159

/* Bring up interfaces which are down */

2160

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

2161

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

2162

char *interface = NULL;

2163

while((interface = argz_next(interfaces, interfaces_size,

2164

interface))){

2165

bool interface_was_up = interface_is_up(interface);

2166

ret = bring_up_interface(interface, delay);

2167

if(not interface_was_up){

2168

if(ret != 0){

2169

errno = ret;

2170

perror_plus("Failed to bring up interface");

2171

} else {

2172

ret_errno = argz_add(&interfaces_to_take_down,

2173

&interfaces_to_take_down_size,

2174

interface);

2175

}

2176

}

2177

}

2178

free(interfaces);

2179

interfaces = NULL;

2180

interfaces_size = 0;

2181

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

2182

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

2032

2183

}

2033

2184

}

2034

2185

2075

2226

/* Connect directly, do not use Zeroconf */

2076

2227

/* (Mainly meant for debugging) */

2077

2228

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

2229

2078

2230

if(address == NULL){

2079

2231

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

2080

2232

exitcode = EX_USAGE;

2085

2237

goto end;

2086

2238

}

2087

2239

2088

uint16_t port;

2240

in_port_t port;

2089

2241

errno = 0;

2090

2242

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

2091

2243

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

2092

or tmpmax != (uint16_t)tmpmax){

2244

or tmpmax != (in_port_t)tmpmax){

2093

2245

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

2094

2246

exitcode = EX_USAGE;

2095

2247

goto end;

2099

2251

goto end;

2100

2252

}

2101

2253

2102

port = (uint16_t)tmpmax;

2254

port = (in_port_t)tmpmax;

2103

2255

*address = '\0';

2104

2256

/* Colon in address indicates IPv6 */

2105

2257

int af;

2155

2307

/* Allocate a new server */

2156

2308

mc.server = avahi_server_new(avahi_simple_poll_get

2157

2309

(mc.simple_poll), &config, NULL,

2158

NULL, &error);

2310

NULL, &ret_errno);

2159

2311

2160

2312

/* Free the Avahi configuration data */

2161

2313

avahi_server_config_free(&config);

2164

2316

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

2165

2317

if(mc.server == NULL){

2166

2318

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

2167

avahi_strerror(error));

2319

avahi_strerror(ret_errno));

2168

2320

exitcode = EX_UNAVAILABLE;

2169

2321

goto end;

2170

2322

}

2238

2390

}

2239

2391

}

2240

2392

2241

/* Run network hooks */

2242

run_network_hooks("stop", interface, delay);

2243

2244

2393

/* Re-raise priviliges */

2245

2394

{

2246

errno = 0;

2247

ret = seteuid(0);

2248

if(ret == -1){

2249

perror_plus("seteuid");

2250

}

2251

2252

/* Take down the network interface */

2253

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

2254

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

2255

if(ret == -1){

2256

perror_plus("ioctl SIOCGIFFLAGS");

2257

} else if(network.ifr_flags & IFF_UP){

2258

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

2259

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

2260

if(ret == -1){

2261

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2395

raise_privileges();

2396

2397

/* Run network hooks */

2398

run_network_hooks("stop", interfaces_hooks != NULL ?

2399

interfaces_hooks : "", delay);

2400

2401

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

2402

{

2403

char *interface = NULL;

2404

while((interface=argz_next(interfaces_to_take_down,

2405

interfaces_to_take_down_size,

2406

interface))){

2407

ret_errno = take_down_interface(interface);

2408

if(ret_errno != 0){

2409

errno = ret_errno;

2410

perror_plus("Failed to take down interface");

2262

2411

}

2263

2412

}

2264

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

2265

if(ret == -1){

2266

perror_plus("close");

2413

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

2414

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

2415

" down\n");

2267

2416

}

2268

2417

}

2269

}

2270

/* Lower privileges permanently */

2271

errno = 0;

2272

ret = setuid(uid);

2273

if(ret == -1){

2274

perror_plus("setuid");

2275

}

2418

2419

lower_privileges_permanently();

2420

}

2421

2422

free(interfaces_to_take_down);

2423

free(interfaces_hooks);

2276

2424

2277

2425

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

2278

2426

if(tempdir_created){