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/*
* ZeroTier One - Network Virtualization Everywhere
* Copyright (C) 2011-2015 ZeroTier, Inc.
*
* 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 <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include <fcntl.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <ifaddrs.h>
#include <algorithm>
#include <utility>
#include "../node/Constants.hpp"
#include "../node/Utils.hpp"
#include "LinuxRoutingTable.hpp"
#define ZT_LINUX_IP_COMMAND "/sbin/ip"
namespace ZeroTier {
LinuxRoutingTable::LinuxRoutingTable()
{
}
LinuxRoutingTable::~LinuxRoutingTable()
{
}
std::vector<RoutingTable::Entry> LinuxRoutingTable::get(bool includeLinkLocal,bool includeLoopback) const
{
char buf[131072];
char *stmp,*stmp2;
std::vector<RoutingTable::Entry> entries;
{
int fd = ::open("/proc/net/route",O_RDONLY);
if (fd <= 0)
buf[0] = (char)0;
else {
int n = (int)::read(fd,buf,sizeof(buf) - 1);
::close(fd);
if (n < 0) n = 0;
buf[n] = (char)0;
}
}
int lineno = 0;
for(char *line=Utils::stok(buf,"\r\n",&stmp);(line);line=Utils::stok((char *)0,"\r\n",&stmp)) {
if (lineno == 0) {
++lineno;
continue; // skip header
}
char *iface = (char *)0;
uint32_t destination = 0;
uint32_t gateway = 0;
int metric = 0;
uint32_t mask = 0;
int fno = 0;
for(char *f=Utils::stok(line,"\t \r\n",&stmp2);(f);f=Utils::stok((char *)0,"\t \r\n",&stmp2)) {
switch(fno) {
case 0: iface = f; break;
case 1: destination = (uint32_t)Utils::hexStrToULong(f); break;
case 2: gateway = (uint32_t)Utils::hexStrToULong(f); break;
case 6: metric = (int)Utils::strToInt(f); break;
case 7: mask = (uint32_t)Utils::hexStrToULong(f); break;
}
++fno;
}
if ((iface)&&(destination)) {
RoutingTable::Entry e;
if (destination)
e.destination.set(&destination,4,Utils::countBits(mask));
e.gateway.set(&gateway,4,0);
e.deviceIndex = 0; // not used on Linux
e.metric = metric;
Utils::scopy(e.device,sizeof(e.device),iface);
if ((e.destination)&&((includeLinkLocal)||(!e.destination.isLinkLocal()))&&((includeLoopback)||((!e.destination.isLoopback())&&(!e.gateway.isLoopback())&&(strcmp(iface,"lo")))))
entries.push_back(e);
}
++lineno;
}
{
int fd = ::open("/proc/net/ipv6_route",O_RDONLY);
if (fd <= 0)
buf[0] = (char)0;
else {
int n = (int)::read(fd,buf,sizeof(buf) - 1);
::close(fd);
if (n < 0) n = 0;
buf[n] = (char)0;
}
}
for(char *line=Utils::stok(buf,"\r\n",&stmp);(line);line=Utils::stok((char *)0,"\r\n",&stmp)) {
char *destination = (char *)0;
unsigned int destPrefixLen = 0;
char *gateway = (char *)0; // next hop in ipv6 terminology
int metric = 0;
char *device = (char *)0;
int fno = 0;
for(char *f=Utils::stok(line,"\t \r\n",&stmp2);(f);f=Utils::stok((char *)0,"\t \r\n",&stmp2)) {
switch(fno) {
case 0: destination = f; break;
case 1: destPrefixLen = (unsigned int)Utils::hexStrToULong(f); break;
case 4: gateway = f; break;
case 5: metric = (int)Utils::hexStrToLong(f); break;
case 9: device = f; break;
}
++fno;
}
if ((device)&&(destination)) {
unsigned char tmp[16];
RoutingTable::Entry e;
Utils::unhex(destination,tmp,16);
if ((!Utils::isZero(tmp,16))&&(tmp[0] != 0xff))
e.destination.set(tmp,16,destPrefixLen);
Utils::unhex(gateway,tmp,16);
e.gateway.set(tmp,16,0);
e.deviceIndex = 0; // not used on Linux
e.metric = metric;
Utils::scopy(e.device,sizeof(e.device),device);
if ((e.destination)&&((includeLinkLocal)||(!e.destination.isLinkLocal()))&&((includeLoopback)||((!e.destination.isLoopback())&&(!e.gateway.isLoopback())&&(strcmp(device,"lo")))))
entries.push_back(e);
}
}
std::sort(entries.begin(),entries.end());
return entries;
}
RoutingTable::Entry LinuxRoutingTable::set(const InetAddress &destination,const InetAddress &gateway,const char *device,int metric)
{
char metstr[128];
if ((!gateway)&&((!device)||(!device[0])))
return RoutingTable::Entry();
Utils::snprintf(metstr,sizeof(metstr),"%d",metric);
if (metric < 0) {
long pid = (long)vfork();
if (pid == 0) {
if (gateway) {
if ((device)&&(device[0])) {
::execl(ZT_LINUX_IP_COMMAND,ZT_LINUX_IP_COMMAND,"route","del",destination.toString().c_str(),"via",gateway.toIpString().c_str(),"dev",device,(const char *)0);
} else {
::execl(ZT_LINUX_IP_COMMAND,ZT_LINUX_IP_COMMAND,"route","del",destination.toString().c_str(),"via",gateway.toIpString().c_str(),(const char *)0);
}
} else {
::execl(ZT_LINUX_IP_COMMAND,ZT_LINUX_IP_COMMAND,"route","del",destination.toString().c_str(),"dev",device,(const char *)0);
}
::_exit(-1);
} else if (pid > 0) {
int exitcode = -1;
::waitpid(pid,&exitcode,0);
}
} else {
long pid = (long)vfork();
if (pid == 0) {
if (gateway) {
if ((device)&&(device[0])) {
::execl(ZT_LINUX_IP_COMMAND,ZT_LINUX_IP_COMMAND,"route","replace",destination.toString().c_str(),"metric",metstr,"via",gateway.toIpString().c_str(),"dev",device,(const char *)0);
} else {
::execl(ZT_LINUX_IP_COMMAND,ZT_LINUX_IP_COMMAND,"route","replace",destination.toString().c_str(),"metric",metstr,"via",gateway.toIpString().c_str(),(const char *)0);
}
} else {
::execl(ZT_LINUX_IP_COMMAND,ZT_LINUX_IP_COMMAND,"route","replace",destination.toString().c_str(),"metric",metstr,"dev",device,(const char *)0);
}
::_exit(-1);
} else if (pid > 0) {
int exitcode = -1;
::waitpid(pid,&exitcode,0);
}
}
std::vector<RoutingTable::Entry> rtab(get(true,true));
std::vector<RoutingTable::Entry>::iterator bestEntry(rtab.end());
for(std::vector<RoutingTable::Entry>::iterator e(rtab.begin());e!=rtab.end();++e) {
if ((e->destination == destination)&&(e->gateway.ipsEqual(gateway))) {
if ((device)&&(device[0])) {
if (!strcmp(device,e->device)) {
if (metric == e->metric)
bestEntry = e;
}
}
if (bestEntry == rtab.end())
bestEntry = e;
}
}
if (bestEntry != rtab.end())
return *bestEntry;
return RoutingTable::Entry();
}
} // namespace ZeroTier
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