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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/param.h>
#include <sys/sysctl.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <net/route.h>
#include <net/if.h>
#include <net/if_dl.h>
#include <ifaddrs.h>
#include <algorithm>
#include <utility>
#include "../node/Constants.hpp"
#include "BSDRoutingTable.hpp"
// All I wanted was the bloody rounting table. I didn't expect the Spanish inquisition.
#define ZT_BSD_ROUTE_CMD "/sbin/route"
namespace ZeroTier {
BSDRoutingTable::BSDRoutingTable()
{
}
BSDRoutingTable::~BSDRoutingTable()
{
}
std::vector<RoutingTable::Entry> BSDRoutingTable::get(bool includeLinkLocal,bool includeLoopback) const
{
std::vector<RoutingTable::Entry> entries;
int mib[6];
size_t needed;
mib[0] = CTL_NET;
mib[1] = PF_ROUTE;
mib[2] = 0;
mib[3] = 0;
mib[4] = NET_RT_DUMP;
mib[5] = 0;
if (!sysctl(mib,6,NULL,&needed,NULL,0)) {
if (needed <= 0)
return entries;
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_flags & RTF_LLINFO) == 0)&&((rtm->rtm_flags & RTF_HOST) == 0)&&((rtm->rtm_flags & RTF_UP) != 0)&&((rtm->rtm_flags & RTF_MULTICAST) == 0)) {
RoutingTable::Entry e;
e.deviceIndex = -9999; // unset
int which = 0;
while (saptr < saend) {
struct sockaddr *sa = (struct sockaddr *)saptr;
unsigned int salen = sa->sa_len;
if (!salen)
break;
// Skip missing fields in rtm_addrs bit field
while ((rtm->rtm_addrs & 1) == 0) {
rtm->rtm_addrs >>= 1;
++which;
if (which > 6)
break;
}
if (which > 6)
break;
rtm->rtm_addrs >>= 1;
switch(which++) {
case 0:
//printf("RTA_DST\n");
if (sa->sa_family == AF_INET6) {
struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sa;
// Nobody expects the Spanish inquisition!
if ((sin6->sin6_addr.s6_addr[0] == 0xfe)&&((sin6->sin6_addr.s6_addr[1] & 0xc0) == 0x80)) {
// Our chief weapon is... in-band signaling!
// Seriously who in the living fuck thought this was a good idea and
// then had the sadistic idea to not document it anywhere? Of course it's
// not like there is any documentation on BSD sysctls anyway.
unsigned int interfaceIndex = ((((unsigned int)sin6->sin6_addr.s6_addr[2]) << 8) & 0xff) | (((unsigned int)sin6->sin6_addr.s6_addr[3]) & 0xff);
sin6->sin6_addr.s6_addr[2] = 0;
sin6->sin6_addr.s6_addr[3] = 0;
if (!sin6->sin6_scope_id)
sin6->sin6_scope_id = interfaceIndex;
}
}
e.destination.set(sa);
break;
case 1:
//printf("RTA_GATEWAY\n");
switch(sa->sa_family) {
case AF_LINK:
e.deviceIndex = (int)((const struct sockaddr_dl *)sa)->sdl_index;
break;
case AF_INET:
case AF_INET6:
e.gateway.set(sa);
break;
}
break;
case 2: {
if (e.destination.isV6()) {
salen = sizeof(struct sockaddr_in6); // Confess!
unsigned int bits = 0;
for(int i=0;i<16;++i) {
unsigned char c = (unsigned char)((const struct sockaddr_in6 *)sa)->sin6_addr.s6_addr[i];
if (c == 0xff)
bits += 8;
else break;
/* must they be multiples of 8? Most of the BSD source I can find says yes..?
else {
while ((c & 0x80) == 0x80) {
++bits;
c <<= 1;
}
break;
}
*/
}
e.destination.setPort(bits);
} else {
salen = sizeof(struct sockaddr_in); // Confess!
e.destination.setPort((unsigned int)Utils::countBits((uint32_t)((const struct sockaddr_in *)sa)->sin_addr.s_addr));
}
//printf("RTA_NETMASK\n");
} break;
/*
case 3:
//printf("RTA_GENMASK\n");
break;
case 4:
//printf("RTA_IFP\n");
break;
case 5:
//printf("RTA_IFA\n");
break;
case 6:
//printf("RTA_AUTHOR\n");
break;
*/
}
saptr += salen;
}
e.metric = (int)rtm->rtm_rmx.rmx_hopcount;
if (e.metric < 0)
e.metric = 0;
if (((includeLinkLocal)||(!e.destination.isLinkLocal()))&&((includeLoopback)||((!e.destination.isLoopback())&&(!e.gateway.isLoopback()))))
entries.push_back(e);
}
next = saend;
}
}
::free(buf);
}
}
for(std::vector<ZeroTier::RoutingTable::Entry>::iterator e1(entries.begin());e1!=entries.end();++e1) {
if ((!e1->device[0])&&(e1->deviceIndex >= 0))
if_indextoname(e1->deviceIndex,e1->device);
}
for(std::vector<ZeroTier::RoutingTable::Entry>::iterator e1(entries.begin());e1!=entries.end();++e1) {
if ((!e1->device[0])&&(e1->gateway)) {
int bestMetric = 9999999;
for(std::vector<ZeroTier::RoutingTable::Entry>::iterator e2(entries.begin());e2!=entries.end();++e2) {
if ((e1->gateway.within(e2->destination))&&(e2->metric <= bestMetric)) {
bestMetric = e2->metric;
Utils::scopy(e1->device,sizeof(e1->device),e2->device);
}
}
}
}
std::sort(entries.begin(),entries.end());
return entries;
}
RoutingTable::Entry BSDRoutingTable::set(const InetAddress &destination,const InetAddress &gateway,const char *device,int metric)
{
if ((!gateway)&&((!device)||(!device[0])))
return RoutingTable::Entry();
std::vector<RoutingTable::Entry> rtab(get(true,true));
for(std::vector<RoutingTable::Entry>::iterator e(rtab.begin());e!=rtab.end();++e) {
if (e->destination == destination) {
if (((!device)||(!device[0]))||(!strcmp(device,e->device))) {
long p = (long)fork();
if (p > 0) {
int exitcode = -1;
::waitpid(p,&exitcode,0);
} else if (p == 0) {
::close(STDOUT_FILENO);
::close(STDERR_FILENO);
::execl(ZT_BSD_ROUTE_CMD,ZT_BSD_ROUTE_CMD,"delete",(destination.isV6() ? "-inet6" : "-inet"),destination.toString().c_str(),(const char *)0);
::_exit(-1);
}
}
}
}
if (metric < 0)
return RoutingTable::Entry();
{
char hcstr[64];
Utils::snprintf(hcstr,sizeof(hcstr),"%d",metric);
long p = (long)fork();
if (p > 0) {
int exitcode = -1;
::waitpid(p,&exitcode,0);
} else if (p == 0) {
::close(STDOUT_FILENO);
::close(STDERR_FILENO);
if (gateway) {
::execl(ZT_BSD_ROUTE_CMD,ZT_BSD_ROUTE_CMD,"add",(destination.isV6() ? "-inet6" : "-inet"),destination.toString().c_str(),gateway.toIpString().c_str(),"-hopcount",hcstr,(const char *)0);
} else if ((device)&&(device[0])) {
::execl(ZT_BSD_ROUTE_CMD,ZT_BSD_ROUTE_CMD,"add",(destination.isV6() ? "-inet6" : "-inet"),destination.toString().c_str(),"-interface",device,"-hopcount",hcstr,(const char *)0);
}
::_exit(-1);
}
}
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
// Enable and build to test routing table interface
#if 0
using namespace ZeroTier;
int main(int argc,char **argv)
{
BSDRoutingTable rt;
printf("<destination> <gateway> <interface> <metric>\n");
std::vector<RoutingTable::Entry> ents(rt.get());
for(std::vector<RoutingTable::Entry>::iterator e(ents.begin());e!=ents.end();++e)
printf("%s\n",e->toString().c_str());
printf("\n");
printf("adding 1.1.1.0 and 2.2.2.0...\n");
rt.set(InetAddress("1.1.1.0",24),InetAddress("1.2.3.4",0),(const char *)0,1);
rt.set(InetAddress("2.2.2.0",24),InetAddress(),"en0",1);
printf("\n");
printf("<destination> <gateway> <interface> <metric>\n");
ents = rt.get();
for(std::vector<RoutingTable::Entry>::iterator e(ents.begin());e!=ents.end();++e)
printf("%s\n",e->toString().c_str());
printf("\n");
printf("deleting 1.1.1.0 and 2.2.2.0...\n");
rt.set(InetAddress("1.1.1.0",24),InetAddress("1.2.3.4",0),(const char *)0,-1);
rt.set(InetAddress("2.2.2.0",24),InetAddress(),"en0",-1);
printf("\n");
printf("<destination> <gateway> <interface> <metric>\n");
ents = rt.get();
for(std::vector<RoutingTable::Entry>::iterator e(ents.begin());e!=ents.end();++e)
printf("%s\n",e->toString().c_str());
printf("\n");
return 0;
}
#endif
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