From c1b0329969d3601fe80ef3298837edac5bdbbed2 Mon Sep 17 00:00:00 2001
From: Adam Ierymenko <adam.ierymenko@gmail.com>
Date: Wed, 28 Oct 2015 09:32:07 -0700
Subject: [PATCH] Only check IP equality to detect external surface changes
(should prevent some spurious resets under symmetric NATs), and simplify some
logic.
---
node/SelfAwareness.cpp | 50 ++++++++++++++++++++----------------------
1 file changed, 24 insertions(+), 26 deletions(-)
diff --git a/node/SelfAwareness.cpp b/node/SelfAwareness.cpp
index b4841544b..856892ffa 100644
--- a/node/SelfAwareness.cpp
+++ b/node/SelfAwareness.cpp
@@ -36,6 +36,7 @@
#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
@@ -65,7 +66,8 @@ private:
};
SelfAwareness::SelfAwareness(const RuntimeEnvironment *renv) :
- RR(renv)
+ RR(renv),
+ _phy(32)
{
}
@@ -77,35 +79,35 @@ void SelfAwareness::iam(const Address &reporter,const InetAddress &reporterPhysi
{
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)||(scope != reporterPhysicalAddress.ipScope()))
+ if (!trusted)
return;
break;
default:
- if (scope != reporterPhysicalAddress.ipScope())
- return;
break;
}
Mutex::Lock _l(_phy_m);
-
PhySurfaceEntry &entry = _phy[PhySurfaceKey(reporter,reporterPhysicalAddress,scope)];
- if ((now - entry.ts) >= ZT_SELFAWARENESS_ENTRY_TIMEOUT) {
+ if ( ((now - entry.ts) < ZT_SELFAWARENESS_ENTRY_TIMEOUT) && (!entry.mySurface.ipsEqual(myPhysicalAddress)) ) {
entry.mySurface = myPhysicalAddress;
entry.ts = now;
- TRACE("learned physical address %s for scope %u as seen from %s(%s) (replaced <null>)",myPhysicalAddress.toString().c_str(),(unsigned int)scope,reporter.toString().c_str(),reporterPhysicalAddress.toString().c_str());
- } else if (entry.mySurface != myPhysicalAddress) {
- entry.mySurface = myPhysicalAddress;
- entry.ts = now;
- TRACE("learned physical address %s for scope %u as seen from %s(%s) (replaced %s, resetting all in scope)",myPhysicalAddress.toString().c_str(),(unsigned int)scope,reporter.toString().c_str(),reporterPhysicalAddress.toString().c_str(),entry.mySurface.toString().c_str());
+ 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 by this remote address to prevent 'thrashing'
+ // 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.
{
@@ -118,26 +120,22 @@ void SelfAwareness::iam(const Address &reporter,const InetAddress &reporterPhysi
}
}
+ // Reset all paths within this scope
_ResetWithinScope rset(RR,now,(InetAddress::IpScope)scope);
RR->topology->eachPeer<_ResetWithinScope &>(rset);
- // For all peers for whom we forgot an address, send a packet indirectly if
- // they are still considered alive so that we will re-establish direct links.
- SharedPtr<Peer> r(RR->topology->getBestRoot());
- if (r) {
- Path *rp = r->getBestPath(now);
- if (rp) {
- for(std::vector< SharedPtr<Peer> >::const_iterator p(rset.peersReset.begin());p!=rset.peersReset.end();++p) {
- if ((*p)->alive(now)) {
- TRACE("sending indirect NOP to %s via %s to re-establish link",(*p)->address().toString().c_str(),r->address().toString().c_str());
- Packet outp((*p)->address(),RR->identity.address(),Packet::VERB_NOP);
- outp.armor((*p)->key(),true);
- rp->send(RR,outp.data(),outp.size(),now);
- }
- }
+ // 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)) {
+ TRACE("sending indirect NOP to %s via %s to re-establish link",(*p)->address().toString().c_str(),r->address().toString().c_str());
+ Packet outp((*p)->address(),RR->identity.address(),Packet::VERB_NOP);
+ RR->sw->send(outp,true,0);
}
}
} else {
+ entry.mySurface = myPhysicalAddress;
entry.ts = now;
}
}