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/*
* ZeroTier One - Global Peer to Peer Ethernet
* Copyright (C) 2011-2014 ZeroTier Networks LLC
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* --
*
* ZeroTier may be used and distributed under the terms of the GPLv3, which
* are available at: http://www.gnu.org/licenses/gpl-3.0.html
*
* If you would like to embed ZeroTier into a commercial application or
* redistribute it in a modified binary form, please contact ZeroTier Networks
* LLC. Start here: http://www.zerotier.com/
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <fcntl.h>
#include <errno.h>
#include <sys/types.h>
#include <set>
#include <string>
#include "Constants.hpp"
#include "SysEnv.hpp"
#include "Utils.hpp"
#include "RuntimeEnvironment.hpp"
#include "NodeConfig.hpp"
#ifdef __UNIX_LIKE__
#include <arpa/inet.h>
#include <sys/socket.h>
#include <unistd.h>
#include <signal.h>
#endif
#ifdef __APPLE__
#include <sys/sysctl.h>
#include <sys/uio.h>
#include <sys/param.h>
#include <net/route.h>
#endif
#ifdef __WINDOWS__
#include <Windows.h>
#include <WinSock2.h>
#endif
namespace ZeroTier {
SysEnv::SysEnv()
{
}
SysEnv::~SysEnv()
{
}
#ifdef __APPLE__
uint64_t SysEnv::getNetworkConfigurationFingerprint(const std::set<std::string> &ignoreDevices)
{
int mib[6];
size_t needed;
uint64_t fingerprint = 5381; // djb2 hash algorithm is used below
// Right now this just scans for changes in default routes. This is not
// totally robust -- it will miss cases where we switch from one 10.0.0.0/24
// network with gateway .1 to another -- but most of the time it'll pick
// up shifts in connectivity. Combined with sleep/wake detection this seems
// pretty solid so far on Mac for detecting when you change locations.
mib[0] = CTL_NET;
mib[1] = PF_ROUTE;
mib[2] = 0;
mib[3] = AF_UNSPEC;
mib[4] = NET_RT_DUMP;
mib[5] = 0;
if (!sysctl(mib,6,NULL,&needed,NULL,0)) {
char *buf = (char *)malloc(needed);
if (buf) {
if (!sysctl(mib,6,buf,&needed,NULL,0)) {
struct rt_msghdr *rtm;
for(char *next=buf,*end=buf+needed;next<end;) {
rtm = (struct rt_msghdr *)next;
char *saptr = (char *)(rtm + 1);
char *saend = next + rtm->rtm_msglen;
if (((rtm->rtm_addrs & RTA_DST))&&((rtm->rtm_addrs & RTA_GATEWAY))) {
int sano = 0;
struct sockaddr *dst = (struct sockaddr *)0;
struct sockaddr *gateway = (struct sockaddr *)0;
while (saptr < saend) {
struct sockaddr *sa = (struct sockaddr *)saptr;
if (!sa->sa_len)
break;
if (sano == 0)
dst = sa;
else if (sano == 1)
gateway = sa;
else if (sano > 1)
break;
++sano;
saptr += sa->sa_len;
}
if ((dst)&&(gateway)) {
if ((dst->sa_family == AF_INET)&&(gateway->sa_family == AF_INET)&&(!((struct sockaddr_in *)dst)->sin_addr.s_addr)) {
fingerprint = ((fingerprint << 5) + fingerprint) + (uint64_t)((struct sockaddr_in *)gateway)->sin_addr.s_addr;
} else if ((dst->sa_family == AF_INET6)&&(gateway->sa_family == AF_INET6)&&(Utils::isZero(((struct sockaddr_in6 *)dst)->sin6_addr.s6_addr,16))) {
for(unsigned int i=0;i<16;++i)
fingerprint = ((fingerprint << 5) + fingerprint) + (uint64_t)((struct sockaddr_in6 *)gateway)->sin6_addr.s6_addr[i];
}
}
}
next = saend;
}
}
free(buf);
}
}
return fingerprint;
}
#endif // __APPLE__
#if defined(__linux__) || defined(linux) || defined(__LINUX__) || defined(__linux)
uint64_t SysEnv::getNetworkConfigurationFingerprint(const std::set<std::string> &ignoreDevices)
{
char buf[16384];
uint64_t fingerprint = 5381; // djb2 hash algorithm is used below
char *t1,*t2;
try {
// Include default IPv4 route if available
int fd = open("/proc/net/route",O_RDONLY);
if (fd > 0) {
long n = read(fd,buf,sizeof(buf) - 1);
::close(fd);
if (n > 0) {
buf[n] = 0;
for(char *line=strtok_r(buf,"\r\n",&t1);(line);line=strtok_r((char *)0,"\r\n",&t1)) {
int fno = 0;
for(char *field=strtok_r(line," \t",&t2);(field);field=strtok_r((char *)0," \t",&t2)) {
if (fno == 0) { // device name
if ((ignoreDevices.count(std::string(field)))||(!strcmp(field,"lo")))
break;
} else if ((fno == 1)||(fno == 2)) { // destination, gateway
if (strlen(field) == 8) { // ignore header junk, use only hex route info
while (*field)
fingerprint = ((fingerprint << 5) + fingerprint) + (uint64_t)*(field++);
}
} else if (fno > 2)
break;
++fno;
}
}
}
}
// Include IPs of IPv6 enabled interfaces if available
fd = open("/proc/net/if_inet6",O_RDONLY);
if (fd > 0) {
long n = read(fd,buf,sizeof(buf) - 1);
::close(fd);
if (n > 0) {
buf[n] = 0;
for(char *line=strtok_r(buf,"\r\n",&t1);(line);line=strtok_r((char *)0,"\r\n",&t1)) {
int fno = 0;
const char *v6ip = (const char *)0;
const char *devname = (const char *)0;
for(char *field=strtok_r(line," \t",&t2);(field);field=strtok_r((char *)0," \t",&t2)) {
switch(fno) {
case 0:
v6ip = field;
break;
case 5:
devname = field;
break;
}
++fno;
}
if ((v6ip)&&(devname)) {
if ((!(ignoreDevices.count(std::string(devname))))&&(strcmp(devname,"lo"))) {
while (*v6ip)
fingerprint = ((fingerprint << 5) + fingerprint) + (uint64_t)*(v6ip++);
}
}
}
}
}
} catch ( ... ) {}
return fingerprint;
}
#endif // __linux__
#ifdef __WINDOWS__
uint64_t SysEnv::getNetworkConfigurationFingerprint(const std::set<std::string> &ignoreDevices)
{
// TODO: windows version
return 1;
}
#endif // __WINDOWS__
} // namespace ZeroTier
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