Fix some deadlock issues, move awareness of broadcast subscription into core, other bug fixes.

7 files changed, 105 insertions, 108 deletions

diff --git a/include/ZeroTierOne.h b/include/ZeroTierOne.h
index 6372641a..45ed626a 100644
--- a/include/ZeroTierOne.h
+++ b/include/ZeroTierOne.h
@@ -395,7 +395,7 @@ enum ZT1_VirtualNetworkConfigOperation
 };
 
 /**
- * Virtual LAN configuration
+ * Virtual network configuration
  */
 typedef struct
 {
@@ -448,9 +448,6 @@ typedef struct
 
 	/**
 	 * If nonzero, this network supports and allows broadcast (ff:ff:ff:ff:ff:ff) traffic
-	 *
-	 * This is really just a hint to user code. If this is true, the user can
-	 * subscribe to the broadcast group. If not, then the user shouldn't.
 	 */
 	int broadcastEnabled;
 
@@ -630,6 +627,10 @@ typedef void ZT1_Node;
  * The supplied config pointer is not guaranteed to remain valid, so make
  * a copy if you want one.
  *
+ * This should not call multicastSubscribe() or other network-modifying
+ * methods, as this could cause a deadlock in multithreaded or interrupt
+ * driven environments.
+ *
  * This must return 0 on success. It can return any OS-dependent error code
  * on failure, and this results in the network being placed into the
  * PORT_ERROR state.
@@ -759,7 +760,7 @@ void ZT1_Node_delete(ZT1_Node *node);
  * @param linkDesperation Link desperation metric for link or protocol over which packet arrived
  * @param packetData Packet data
  * @param packetLength Packet length
- * @param nextBackgroundTaskDeadline Value/result: set to deadline for next call to one of the three processXXX() methods
+ * @param nextBackgroundTaskDeadline Value/result: set to deadline for next call to processBackgroundTasks()
  * @return OK (0) or error code if a fatal error condition has occurred
  */
 enum ZT1_ResultCode ZT1_Node_processWirePacket(
@@ -769,7 +770,7 @@ enum ZT1_ResultCode ZT1_Node_processWirePacket(
 	unsigned int linkDesperation,
 	const void *packetData,
 	unsigned int packetLength,
-	uint64_t *nextBackgroundTaskDeadline);
+	volatile uint64_t *nextBackgroundTaskDeadline);
 
 /**
  * Process a frame from a virtual network port (tap)
@@ -783,7 +784,7 @@ enum ZT1_ResultCode ZT1_Node_processWirePacket(
  * @param vlanId 10-bit VLAN ID or 0 if none
  * @param frameData Frame payload data
  * @param frameLength Frame payload length
- * @param nextBackgroundTaskDeadline Value/result: set to deadline for next call to one of the three processXXX() methods
+ * @param nextBackgroundTaskDeadline Value/result: set to deadline for next call to processBackgroundTasks()
  * @return OK (0) or error code if a fatal error condition has occurred
  */
 enum ZT1_ResultCode ZT1_Node_processVirtualNetworkFrame(
@@ -796,17 +797,17 @@ enum ZT1_ResultCode ZT1_Node_processVirtualNetworkFrame(
 	unsigned int vlanId,
 	const void *frameData,
 	unsigned int frameLength,
-	uint64_t *nextBackgroundTaskDeadline);
+	volatile uint64_t *nextBackgroundTaskDeadline);
 
 /**
- * Perform required periodic operations even if no new frames or packets have arrived
+ * Perform periodic background operations
  *
  * @param node Node instance
  * @param now Current clock in milliseconds
- * @param nextBackgroundTaskDeadline Value/result: set to deadline for next call to one of the three processXXX() methods
+ * @param nextBackgroundTaskDeadline Value/result: set to deadline for next call to processBackgroundTasks()
  * @return OK (0) or error code if a fatal error condition has occurred
  */
-enum ZT1_ResultCode ZT1_Node_processBackgroundTasks(ZT1_Node *node,uint64_t now,uint64_t *nextBackgroundTaskDeadline);
+enum ZT1_ResultCode ZT1_Node_processBackgroundTasks(ZT1_Node *node,uint64_t now,volatile uint64_t *nextBackgroundTaskDeadline);
 
 /**
  * Join a network
diff --git a/node/Network.cpp b/node/Network.cpp
index ba0ee984..7fa17ef1 100644
--- a/node/Network.cpp
+++ b/node/Network.cpp
@@ -47,6 +47,7 @@ Network::Network(const RuntimeEnvironment *renv,uint64_t nwid) :
 	_id(nwid),
 	_mac(renv->identity.address(),nwid),
 	_enabled(true),
+	_portInitialized(false),
 	_lastConfigUpdate(0),
 	_destroyed(false),
 	_netconfFailure(NETCONF_FAILURE_NONE),
@@ -84,7 +85,6 @@ Network::Network(const RuntimeEnvironment *renv,uint64_t nwid) :
 				const char *e = p + mcdb.length();
 				if (!memcmp("ZTMCD0",p,6)) {
 					p += 6;
-					Mutex::Lock _l(_lock);
 					while (p != e) {
 						CertificateOfMembership com;
 						com.deserialize2(p,e);
@@ -97,9 +97,12 @@ Network::Network(const RuntimeEnvironment *renv,uint64_t nwid) :
 		} catch ( ... ) {} // ignore invalid MCDB, we'll re-learn from peers
 	}
 
-	ZT1_VirtualNetworkConfig ctmp;
-	_externalConfig(&ctmp);
-	_portError = RR->node->configureVirtualNetworkPort(_id,ZT1_VIRTUAL_NETWORK_CONFIG_OPERATION_UP,&ctmp);
+	if (!_portInitialized) {
+		ZT1_VirtualNetworkConfig ctmp;
+		_externalConfig(&ctmp);
+		_portError = RR->node->configureVirtualNetworkPort(_id,ZT1_VIRTUAL_NETWORK_CONFIG_OPERATION_UP,&ctmp);
+		_portInitialized = true;
+	}
 }
 
 Network::~Network()
@@ -145,6 +148,8 @@ std::vector<MulticastGroup> Network::allMulticastGroups() const
 		if (!std::binary_search(mgs.begin(),oldend,i->first))
 			mgs.push_back(i->first);
 	}
+	if ((_config)&&(_config->enableBroadcast()))
+		mgs.push_back(Network::BROADCAST);
 	std::sort(mgs.begin(),mgs.end());
 	return mgs;
 }
@@ -161,11 +166,13 @@ bool Network::subscribedToMulticastGroup(const MulticastGroup &mg,bool includeBr
 
 void Network::multicastSubscribe(const MulticastGroup &mg)
 {
-	Mutex::Lock _l(_lock);
-	if (std::binary_search(_myMulticastGroups.begin(),_myMulticastGroups.end(),mg))
-		return;
-	_myMulticastGroups.push_back(mg);
-	std::sort(_myMulticastGroups.begin(),_myMulticastGroups.end());
+	{
+		Mutex::Lock _l(_lock);
+		if (std::binary_search(_myMulticastGroups.begin(),_myMulticastGroups.end(),mg))
+			return;
+		_myMulticastGroups.push_back(mg);
+		std::sort(_myMulticastGroups.begin(),_myMulticastGroups.end());
+	}
 	_announceMulticastGroups();
 }
 
@@ -183,19 +190,22 @@ void Network::multicastUnsubscribe(const MulticastGroup &mg)
 
 bool Network::applyConfiguration(const SharedPtr<NetworkConfig> &conf)
 {
-	Mutex::Lock _l(_lock);
-	if (_destroyed)
+	if (_destroyed) // sanity check
 		return false;
 	try {
 		if ((conf->networkId() == _id)&&(conf->issuedTo() == RR->identity.address())) {
-			_config = conf;
-			_lastConfigUpdate = RR->node->now();
-			_netconfFailure = NETCONF_FAILURE_NONE;
-
 			ZT1_VirtualNetworkConfig ctmp;
-			_externalConfig(&ctmp);
-			_portError = RR->node->configureVirtualNetworkPort(_id,ZT1_VIRTUAL_NETWORK_CONFIG_OPERATION_CONFIG_UPDATE,&ctmp);
-
+			bool portInitialized;
+			{
+				Mutex::Lock _l(_lock);
+				_config = conf;
+				_lastConfigUpdate = RR->node->now();
+				_netconfFailure = NETCONF_FAILURE_NONE;
+				_externalConfig(&ctmp);
+				portInitialized = _portInitialized;
+				_portInitialized = true;
+			}
+			_portError = RR->node->configureVirtualNetworkPort(_id,(portInitialized) ? ZT1_VIRTUAL_NETWORK_CONFIG_OPERATION_CONFIG_UPDATE : ZT1_VIRTUAL_NETWORK_CONFIG_OPERATION_UP,&ctmp);
 			return true;
 		} else {
 			TRACE("ignored invalid configuration for network %.16llx (configuration contains mismatched network ID or issued-to address)",(unsigned long long)_id);
@@ -462,7 +472,7 @@ ZT1_VirtualNetworkStatus Network::_status() const
 		case NETCONF_FAILURE_NOT_FOUND:
 			return ZT1_NETWORK_STATUS_NOT_FOUND;
 		case NETCONF_FAILURE_NONE:
-			return ((_lastConfigUpdate > 0) ? ZT1_NETWORK_STATUS_OK : ZT1_NETWORK_STATUS_REQUESTING_CONFIGURATION);
+			return ((_config) ? ZT1_NETWORK_STATUS_OK : ZT1_NETWORK_STATUS_REQUESTING_CONFIGURATION);
 		default:
 			return ZT1_NETWORK_STATUS_PORT_ERROR;
 	}
diff --git a/node/Network.hpp b/node/Network.hpp
index 08d9e527..213b44c5 100644
--- a/node/Network.hpp
+++ b/node/Network.hpp
@@ -65,6 +65,16 @@ class Network : NonCopyable
 
 public:
 	/**
+	 * Broadcast multicast group: ff:ff:ff:ff:ff:ff / 0
+	 */
+	static const MulticastGroup BROADCAST;
+
+	/**
+	 * Construct a new network
+	 *
+	 * Note that init() should be called immediately after the network is
+	 * constructed to actually configure the port.
+	 *
 	 * @param renv Runtime environment
 	 * @param nwid Network ID
 	 */
@@ -73,11 +83,6 @@ public:
 	~Network();
 
 	/**
-	 * Broadcast multicast group: ff:ff:ff:ff:ff:ff / 0
-	 */
-	static const MulticastGroup BROADCAST;
-
-	/**
 	 * @return Network ID
 	 */
 	inline uint64_t id() const throw() { return _id; }
@@ -348,7 +353,8 @@ private:
 	const RuntimeEnvironment *RR;
 	uint64_t _id;
 	MAC _mac; // local MAC address
-	bool _enabled;
+	volatile bool _enabled;
+	volatile bool _portInitialized;
 
 	std::vector< MulticastGroup > _myMulticastGroups; // multicast groups that we belong to including those behind us (updated periodically)
 	std::map< MulticastGroup,uint64_t > _multicastGroupsBehindMe; // multicast groups bridged to us and when we last saw activity on each
@@ -370,7 +376,7 @@ private:
 		NETCONF_FAILURE_NOT_FOUND,
 		NETCONF_FAILURE_INIT_FAILED
 	} _netconfFailure;
-	int _portError; // return value from port config callback
+	volatile int _portError; // return value from port config callback
 
 	Mutex _lock;
 
diff --git a/node/Node.cpp b/node/Node.cpp
index 6cdfc650..c6ae54bd 100644
--- a/node/Node.cpp
+++ b/node/Node.cpp
@@ -152,16 +152,10 @@ ZT1_ResultCode Node::processWirePacket(
 	unsigned int linkDesperation,
 	const void *packetData,
 	unsigned int packetLength,
-	uint64_t *nextBackgroundTaskDeadline)
+	volatile uint64_t *nextBackgroundTaskDeadline)
 {
-	if (now >= *nextBackgroundTaskDeadline) {
-		ZT1_ResultCode rc = processBackgroundTasks(now,nextBackgroundTaskDeadline);
-		if (rc != ZT1_RESULT_OK)
-			return rc;
-	} else _now = now;
-
+	_now = now;
 	RR->sw->onRemotePacket(*(reinterpret_cast<const InetAddress *>(remoteAddress)),linkDesperation,packetData,packetLength);
-
 	return ZT1_RESULT_OK;
 }
 
@@ -174,20 +168,14 @@ ZT1_ResultCode Node::processVirtualNetworkFrame(
 	unsigned int vlanId,
 	const void *frameData,
 	unsigned int frameLength,
-	uint64_t *nextBackgroundTaskDeadline)
+	volatile uint64_t *nextBackgroundTaskDeadline)
 {
-	if (now >= *nextBackgroundTaskDeadline) {
-		ZT1_ResultCode rc = processBackgroundTasks(now,nextBackgroundTaskDeadline);
-		if (rc != ZT1_RESULT_OK)
-			return rc;
-	} else _now = now;
-
-	SharedPtr<Network> nw(network(nwid));
-	if (nw)
+	_now = now;
+	SharedPtr<Network> nw(this->network(nwid));
+	if (nw) {
 		RR->sw->onLocalEthernet(nw,MAC(sourceMac),MAC(destMac),etherType,vlanId,frameData,frameLength);
-	else return ZT1_RESULT_ERROR_NETWORK_NOT_FOUND;
-
-	return ZT1_RESULT_OK;
+		return ZT1_RESULT_OK;
+	} else return ZT1_RESULT_ERROR_NETWORK_NOT_FOUND;
 }
 
 class _PingPeersThatNeedPing
@@ -217,7 +205,7 @@ private:
 	std::vector<Address> _supernodes;
 };
 
-ZT1_ResultCode Node::processBackgroundTasks(uint64_t now,uint64_t *nextBackgroundTaskDeadline)
+ZT1_ResultCode Node::processBackgroundTasks(uint64_t now,volatile uint64_t *nextBackgroundTaskDeadline)
 {
 	_now = now;
 	Mutex::Lock bl(_backgroundTasksLock);
@@ -260,6 +248,7 @@ ZT1_ResultCode Node::processBackgroundTasks(uint64_t now,uint64_t *nextBackgroun
 			*(reinterpret_cast<uint32_t *>(beacon)) = RR->prng->next32();
 			*(reinterpret_cast<uint32_t *>(beacon + 4)) = RR->prng->next32();
 			RR->identity.address().copyTo(beacon + 8,5);
+			RR->antiRec->logOutgoingZT(beacon,13);
 			putPacket(ZT_DEFAULTS.v4Broadcast,beacon,13,0);
 		}
 	}
@@ -292,9 +281,9 @@ ZT1_ResultCode Node::processBackgroundTasks(uint64_t now,uint64_t *nextBackgroun
 ZT1_ResultCode Node::join(uint64_t nwid)
 {
 	Mutex::Lock _l(_networks_m);
-	SharedPtr<Network> &nw = _networks[nwid];
-	if (!nw)
-		nw = SharedPtr<Network>(new Network(RR,nwid));
+	SharedPtr<Network> &nwe = _networks[nwid];
+	if (!nwe)
+		nwe = SharedPtr<Network>(new Network(RR,nwid));
 	return ZT1_RESULT_OK;
 }
 
@@ -311,20 +300,20 @@ ZT1_ResultCode Node::leave(uint64_t nwid)
 
 ZT1_ResultCode Node::multicastSubscribe(uint64_t nwid,uint64_t multicastGroup,unsigned long multicastAdi)
 {
-	Mutex::Lock _l(_networks_m);
-	std::map< uint64_t,SharedPtr<Network> >::iterator nw(_networks.find(nwid));
-	if (nw != _networks.end())
-		nw->second->multicastSubscribe(MulticastGroup(MAC(multicastGroup),(uint32_t)(multicastAdi & 0xffffffff)));
-	return ZT1_RESULT_OK;
+	SharedPtr<Network> nw(this->network(nwid));
+	if (nw) {
+		nw->multicastSubscribe(MulticastGroup(MAC(multicastGroup),(uint32_t)(multicastAdi & 0xffffffff)));
+		return ZT1_RESULT_OK;
+	} else return ZT1_RESULT_ERROR_NETWORK_NOT_FOUND;
 }
 
 ZT1_ResultCode Node::multicastUnsubscribe(uint64_t nwid,uint64_t multicastGroup,unsigned long multicastAdi)
 {
-	Mutex::Lock _l(_networks_m);
-	std::map< uint64_t,SharedPtr<Network> >::iterator nw(_networks.find(nwid));
-	if (nw != _networks.end())
-		nw->second->multicastUnsubscribe(MulticastGroup(MAC(multicastGroup),(uint32_t)(multicastAdi & 0xffffffff)));
-	return ZT1_RESULT_OK;
+	SharedPtr<Network> nw(this->network(nwid));
+	if (nw) {
+		nw->multicastUnsubscribe(MulticastGroup(MAC(multicastGroup),(uint32_t)(multicastAdi & 0xffffffff)));
+		return ZT1_RESULT_OK;
+	} else return ZT1_RESULT_ERROR_NETWORK_NOT_FOUND;
 }
 
 uint64_t Node::address() const
@@ -531,7 +520,7 @@ enum ZT1_ResultCode ZT1_Node_processWirePacket(
 	unsigned int linkDesperation,
 	const void *packetData,
 	unsigned int packetLength,
-	uint64_t *nextBackgroundTaskDeadline)
+	volatile uint64_t *nextBackgroundTaskDeadline)
 {
 	try {
 		return reinterpret_cast<ZeroTier::Node *>(node)->processWirePacket(now,remoteAddress,linkDesperation,packetData,packetLength,nextBackgroundTaskDeadline);
@@ -553,7 +542,7 @@ enum ZT1_ResultCode ZT1_Node_processVirtualNetworkFrame(
 	unsigned int vlanId,
 	const void *frameData,
 	unsigned int frameLength,
-	uint64_t *nextBackgroundTaskDeadline)
+	volatile uint64_t *nextBackgroundTaskDeadline)
 {
 	try {
 		return reinterpret_cast<ZeroTier::Node *>(node)->processVirtualNetworkFrame(now,nwid,sourceMac,destMac,etherType,vlanId,frameData,frameLength,nextBackgroundTaskDeadline);
@@ -564,7 +553,7 @@ enum ZT1_ResultCode ZT1_Node_processVirtualNetworkFrame(
 	}
 }
 
-enum ZT1_ResultCode ZT1_Node_processBackgroundTasks(ZT1_Node *node,uint64_t now,uint64_t *nextBackgroundTaskDeadline)
+enum ZT1_ResultCode ZT1_Node_processBackgroundTasks(ZT1_Node *node,uint64_t now,volatile uint64_t *nextBackgroundTaskDeadline)
 {
 	try {
 		return reinterpret_cast<ZeroTier::Node *>(node)->processBackgroundTasks(now,nextBackgroundTaskDeadline);
diff --git a/node/Node.hpp b/node/Node.hpp
index cd8914e6..429e5171 100644
--- a/node/Node.hpp
+++ b/node/Node.hpp
@@ -83,7 +83,7 @@ public:
 		unsigned int linkDesperation,
 		const void *packetData,
 		unsigned int packetLength,
-		uint64_t *nextBackgroundTaskDeadline);
+		volatile uint64_t *nextBackgroundTaskDeadline);
 	ZT1_ResultCode processVirtualNetworkFrame(
 		uint64_t now,
 		uint64_t nwid,
@@ -93,8 +93,8 @@ public:
 		unsigned int vlanId,
 		const void *frameData,
 		unsigned int frameLength,
-		uint64_t *nextBackgroundTaskDeadline);
-	ZT1_ResultCode processBackgroundTasks(uint64_t now,uint64_t *nextBackgroundTaskDeadline);
+		volatile uint64_t *nextBackgroundTaskDeadline);
+	ZT1_ResultCode processBackgroundTasks(uint64_t now,volatile uint64_t *nextBackgroundTaskDeadline);
 	ZT1_ResultCode join(uint64_t nwid);
 	ZT1_ResultCode leave(uint64_t nwid);
 	ZT1_ResultCode multicastSubscribe(uint64_t nwid,uint64_t multicastGroup,unsigned long multicastAdi);
diff --git a/node/Switch.cpp b/node/Switch.cpp
index 3710158d..6bc044c0 100644
--- a/node/Switch.cpp
+++ b/node/Switch.cpp
@@ -153,7 +153,7 @@ void Switch::onLocalEthernet(const SharedPtr<Network> &network,const MAC &from,c
 			return;
 		}
 
-		//TRACE("%.16llx: MULTICAST %s -> %s %s %u",network->id(),from.toString().c_str(),mg.toString().c_str(),etherTypeName(etherType),len);
+		TRACE("%.16llx: MULTICAST %s -> %s %s %u",network->id(),from.toString().c_str(),mg.toString().c_str(),etherTypeName(etherType),len);
 
 		RR->mc->send(
 			((!nconf->isPublic())&&(nconf->com())) ? &(nconf->com()) : (const CertificateOfMembership *)0,
@@ -171,7 +171,7 @@ void Switch::onLocalEthernet(const SharedPtr<Network> &network,const MAC &from,c
 	}
 
 	if (to[0] == MAC::firstOctetForNetwork(network->id())) {
-		// Destination is another ZeroTier peer
+		// Destination is another ZeroTier peer on the same network
 
 		Address toZT(to.toAddress(network->id()));
 		if (network->isAllowed(toZT)) {
@@ -203,8 +203,10 @@ void Switch::onLocalEthernet(const SharedPtr<Network> &network,const MAC &from,c
 				outp.compress();
 				send(outp,true);
 			}
+
+			TRACE("%.16llx: UNICAST: %s -> %s etherType==%s(%.4x) vlanId==%u len==%u fromBridged==%d",network->id(),from.toString().c_str(),to.toString().c_str(),etherTypeName(etherType),etherType,vlanId,len,(int)fromBridged);
 		} else {
-			TRACE("%.16llx: UNICAST: %s -> %s %s dropped, destination not a member of private network",network->id(),from.toString().c_str(),to.toString().c_str(),etherTypeName(etherType));
+			TRACE("%.16llx: UNICAST: %s -> %s etherType==%s dropped, destination not a member of private network",network->id(),from.toString().c_str(),to.toString().c_str(),etherTypeName(etherType));
 		}
 
 		return;
diff --git a/service/One.cpp b/service/One.cpp
index bc42bba8..287f7813 100644
--- a/service/One.cpp
+++ b/service/One.cpp
@@ -228,19 +228,22 @@ public:
 
 				uint64_t dl = _nextBackgroundTaskDeadline;
 				uint64_t now = OSUtils::now();
-
 				if (dl <= now) {
-					if ((now - lastTapMulticastGroupCheck) >= ZT_TAP_CHECK_MULTICAST_INTERVAL) {
-						lastTapMulticastGroupCheck = now;
-						Mutex::Lock _l(_taps_m);
-						for(std::map< uint64_t,EthernetTap *>::const_iterator t(_taps.begin());t!=_taps.end();++t)
-							_updateMulticastGroups(t->first,t->second);
-					}
-
 					_node->processBackgroundTasks(now,&_nextBackgroundTaskDeadline);
-
 					dl = _nextBackgroundTaskDeadline;
-					now = OSUtils::now();
+				}
+
+				if ((now - lastTapMulticastGroupCheck) >= ZT_TAP_CHECK_MULTICAST_INTERVAL) {
+					lastTapMulticastGroupCheck = now;
+					Mutex::Lock _l(_taps_m);
+					for(std::map< uint64_t,EthernetTap *>::const_iterator t(_taps.begin());t!=_taps.end();++t) {
+						std::vector<MulticastGroup> added,removed;
+						t->second->scanMulticastGroups(added,removed);
+						for(std::vector<MulticastGroup>::iterator m(added.begin());m!=added.end();++m)
+							_node->multicastSubscribe(t->first,m->mac().toInt(),m->adi());
+						for(std::vector<MulticastGroup>::iterator m(removed.begin());m!=removed.end();++m)
+							_node->multicastUnsubscribe(t->first,m->mac().toInt(),m->adi());
+					}
 				}
 
 				const unsigned long delay = (dl > now) ? (unsigned long)(dl - now) : 100;
@@ -409,7 +412,7 @@ public:
 							StapFrameHandler,
 							(void *)this))).first;
 					} catch ( ... ) {
-						return -999;
+						return -999; // tap init failed
 					}
 				}
 				// fall through...
@@ -432,11 +435,8 @@ public:
 							t->second->removeIp(*ip);
 					}
 					assignedIps.swap(newAssignedIps);
-
-					_updateMulticastGroups(t->first,t->second);
-					if (nwc->broadcastEnabled)
-						_node->multicastSubscribe(nwid,0xffffffffffffULL,0);
-					else _node->multicastUnsubscribe(nwid,0xffffffffffffULL,0);
+				} else {
+					return -999; // tap init failed
 				}
 				break;
 			case ZT1_VIRTUAL_NETWORK_CONFIG_OPERATION_DOWN:
@@ -627,17 +627,6 @@ private:
 		return p;
 	}
 
-	void _updateMulticastGroups(uint64_t nwid,EthernetTap *tap)
-	{
-		// assumes _taps_m is locked
-		std::vector<MulticastGroup> added,removed;
-		tap->scanMulticastGroups(added,removed);
-		for(std::vector<MulticastGroup>::iterator m(added.begin());m!=added.end();++m)
-			_node->multicastSubscribe(nwid,m->mac().toInt(),m->adi());
-		for(std::vector<MulticastGroup>::iterator m(removed.begin());m!=removed.end();++m)
-			_node->multicastUnsubscribe(nwid,m->mac().toInt(),m->adi());
-	}
-
 	const std::string _homePath;
 	Phy<OneImpl *> _phy;
 	NetworkConfigMaster *_master;
@@ -648,7 +637,7 @@ private:
 	PhySocket *_v4TcpListenSocket;
 	PhySocket *_v6TcpListenSocket;
 	ControlPlane *_controlPlane;
-	uint64_t _nextBackgroundTaskDeadline;
+	volatile uint64_t _nextBackgroundTaskDeadline;
 
 	std::map< uint64_t,EthernetTap * > _taps;
 	std::map< uint64_t,std::vector<InetAddress> > _tapAssignedIps; // ZeroTier assigned IPs, not user or dhcp assigned