ZeroTierOne/node/SelfAwareness.cpp
2015-10-28 10:01:32 -07:00

155 lines
4.9 KiB
C++

/*
* 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 <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "Constants.hpp"
#include "SelfAwareness.hpp"
#include "RuntimeEnvironment.hpp"
#include "Node.hpp"
#include "Topology.hpp"
#include "Packet.hpp"
#include "Peer.hpp"
#include "Switch.hpp"
// Entry timeout -- make it fairly long since this is just to prevent stale buildup
#define ZT_SELFAWARENESS_ENTRY_TIMEOUT 3600000
namespace ZeroTier {
class _ResetWithinScope
{
public:
_ResetWithinScope(const RuntimeEnvironment *renv,uint64_t now,InetAddress::IpScope scope) :
RR(renv),
_now(now),
_scope(scope) {}
inline void operator()(Topology &t,const SharedPtr<Peer> &p)
{
if (p->resetWithinScope(RR,_scope,_now))
peersReset.push_back(p);
}
std::vector< SharedPtr<Peer> > peersReset;
private:
const RuntimeEnvironment *RR;
uint64_t _now;
InetAddress::IpScope _scope;
};
SelfAwareness::SelfAwareness(const RuntimeEnvironment *renv) :
RR(renv),
_phy(32)
{
}
SelfAwareness::~SelfAwareness()
{
}
void SelfAwareness::iam(const Address &reporter,const InetAddress &reporterPhysicalAddress,const InetAddress &myPhysicalAddress,bool trusted,uint64_t now)
{
const InetAddress::IpScope scope = myPhysicalAddress.ipScope();
// This would be weird, e.g. a public IP talking to 10.0.0.1, so just ignore it.
// If your network is this weird it's probably not reliable information.
if (scope != reporterPhysicalAddress.ipScope())
return;
// Some scopes we ignore, and global scope IPs are only used for this
// mechanism if they come from someone we trust (e.g. a root).
switch(scope) {
case InetAddress::IP_SCOPE_NONE:
case InetAddress::IP_SCOPE_LOOPBACK:
case InetAddress::IP_SCOPE_MULTICAST:
return;
case InetAddress::IP_SCOPE_GLOBAL:
if (!trusted)
return;
break;
default:
break;
}
Mutex::Lock _l(_phy_m);
PhySurfaceEntry &entry = _phy[PhySurfaceKey(reporter,reporterPhysicalAddress,scope)];
if ( ((now - entry.ts) < ZT_SELFAWARENESS_ENTRY_TIMEOUT) && (!entry.mySurface.ipsEqual(myPhysicalAddress)) ) {
entry.mySurface = myPhysicalAddress;
entry.ts = now;
TRACE("physical address %s for scope %u as seen from %s(%s) differs from %s, resetting paths in scope",myPhysicalAddress.toString().c_str(),(unsigned int)scope,reporter.toString().c_str(),reporterPhysicalAddress.toString().c_str(),entry.mySurface.toString().c_str());
// Erase all entries in this scope that were not reported from this remote address to prevent 'thrashing'
// due to multiple reports of endpoint change.
// Don't use 'entry' after this since hash table gets modified.
{
Hashtable< PhySurfaceKey,PhySurfaceEntry >::Iterator i(_phy);
PhySurfaceKey *k = (PhySurfaceKey *)0;
PhySurfaceEntry *e = (PhySurfaceEntry *)0;
while (i.next(k,e)) {
if ((k->reporterPhysicalAddress != reporterPhysicalAddress)&&(k->scope == scope))
_phy.erase(*k);
}
}
// Reset all paths within this scope
_ResetWithinScope rset(RR,now,(InetAddress::IpScope)scope);
RR->topology->eachPeer<_ResetWithinScope &>(rset);
// Send a NOP to all peers for whom we forgot a path. This will cause direct
// links to be re-established if possible, possibly using a root server or some
// other relay.
for(std::vector< SharedPtr<Peer> >::const_iterator p(rset.peersReset.begin());p!=rset.peersReset.end();++p) {
if ((*p)->alive(now)) {
Packet outp((*p)->address(),RR->identity.address(),Packet::VERB_NOP);
RR->sw->send(outp,true,0);
}
}
} else {
entry.mySurface = myPhysicalAddress;
entry.ts = now;
}
}
void SelfAwareness::clean(uint64_t now)
{
Mutex::Lock _l(_phy_m);
Hashtable< PhySurfaceKey,PhySurfaceEntry >::Iterator i(_phy);
PhySurfaceKey *k = (PhySurfaceKey *)0;
PhySurfaceEntry *e = (PhySurfaceEntry *)0;
while (i.next(k,e)) {
if ((now - e->ts) >= ZT_SELFAWARENESS_ENTRY_TIMEOUT)
_phy.erase(*k);
}
}
} // namespace ZeroTier