re-added zto dir with no git info0.3.0

1 files changed, 1349 insertions, 0 deletions

diff --git a/zerotierone/node/IncomingPacket.cpp b/zerotierone/node/IncomingPacket.cpp
new file mode 100644
index 0000000..9e0226b
--- /dev/null
+++ b/zerotierone/node/IncomingPacket.cpp
@@ -0,0 +1,1349 @@
+/*
+ * ZeroTier One - Network Virtualization Everywhere
+ * Copyright (C) 2011-2016  ZeroTier, Inc.  https://www.zerotier.com/
+ *
+ * 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/>.
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+
+#include "../version.h"
+#include "../include/ZeroTierOne.h"
+
+#include "Constants.hpp"
+#include "RuntimeEnvironment.hpp"
+#include "IncomingPacket.hpp"
+#include "Topology.hpp"
+#include "Switch.hpp"
+#include "Peer.hpp"
+#include "NetworkController.hpp"
+#include "SelfAwareness.hpp"
+#include "Salsa20.hpp"
+#include "SHA512.hpp"
+#include "World.hpp"
+#include "Cluster.hpp"
+#include "Node.hpp"
+#include "DeferredPackets.hpp"
+
+namespace ZeroTier {
+
+bool IncomingPacket::tryDecode(const RuntimeEnvironment *RR,bool deferred)
+{
+	const Address sourceAddress(source());
+	try {
+		if ((cipher() == ZT_PROTO_CIPHER_SUITE__C25519_POLY1305_NONE)&&(verb() == Packet::VERB_HELLO)) {
+			// Unencrypted HELLOs require some potentially expensive verification, so
+			// do this in the background if background processing is enabled.
+			if ((RR->dpEnabled > 0)&&(!deferred)) {
+				RR->dp->enqueue(this);
+				return true; // 'handled' via deferring to background thread(s)
+			} else {
+				// A null pointer for peer to _doHELLO() tells it to run its own
+				// special internal authentication logic. This is done for unencrypted
+				// HELLOs to learn new identities, etc.
+				SharedPtr<Peer> tmp;
+				return _doHELLO(RR,tmp);
+			}
+		}
+
+		SharedPtr<Peer> peer(RR->topology->getPeer(sourceAddress));
+		if (peer) {
+			if (!dearmor(peer->key())) {
+				TRACE("dropped packet from %s(%s), MAC authentication failed (size: %u)",peer->address().toString().c_str(),_remoteAddress.toString().c_str(),size());
+				return true;
+			}
+			if (!uncompress()) {
+				TRACE("dropped packet from %s(%s), compressed data invalid",peer->address().toString().c_str(),_remoteAddress.toString().c_str());
+				return true;
+			}
+
+			const Packet::Verb v = verb();
+			//TRACE("<< %s from %s(%s)",Packet::verbString(v),sourceAddress.toString().c_str(),_remoteAddress.toString().c_str());
+			switch(v) {
+				//case Packet::VERB_NOP:
+				default: // ignore unknown verbs, but if they pass auth check they are "received"
+					peer->received(_localAddress,_remoteAddress,hops(),packetId(),v,0,Packet::VERB_NOP);
+					return true;
+
+				case Packet::VERB_HELLO:                          return _doHELLO(RR,peer);
+				case Packet::VERB_ERROR:                          return _doERROR(RR,peer);
+				case Packet::VERB_OK:                             return _doOK(RR,peer);
+				case Packet::VERB_WHOIS:                          return _doWHOIS(RR,peer);
+				case Packet::VERB_RENDEZVOUS:                     return _doRENDEZVOUS(RR,peer);
+				case Packet::VERB_FRAME:                          return _doFRAME(RR,peer);
+				case Packet::VERB_EXT_FRAME:                      return _doEXT_FRAME(RR,peer);
+				case Packet::VERB_ECHO:                           return _doECHO(RR,peer);
+				case Packet::VERB_MULTICAST_LIKE:                 return _doMULTICAST_LIKE(RR,peer);
+				case Packet::VERB_NETWORK_MEMBERSHIP_CERTIFICATE: return _doNETWORK_MEMBERSHIP_CERTIFICATE(RR,peer);
+				case Packet::VERB_NETWORK_CONFIG_REQUEST:         return _doNETWORK_CONFIG_REQUEST(RR,peer);
+				case Packet::VERB_NETWORK_CONFIG_REFRESH:         return _doNETWORK_CONFIG_REFRESH(RR,peer);
+				case Packet::VERB_MULTICAST_GATHER:               return _doMULTICAST_GATHER(RR,peer);
+				case Packet::VERB_MULTICAST_FRAME:                return _doMULTICAST_FRAME(RR,peer);
+				case Packet::VERB_PUSH_DIRECT_PATHS:              return _doPUSH_DIRECT_PATHS(RR,peer);
+				case Packet::VERB_CIRCUIT_TEST:                   return _doCIRCUIT_TEST(RR,peer);
+				case Packet::VERB_CIRCUIT_TEST_REPORT:            return _doCIRCUIT_TEST_REPORT(RR,peer);
+				case Packet::VERB_REQUEST_PROOF_OF_WORK:          return _doREQUEST_PROOF_OF_WORK(RR,peer);
+			}
+		} else {
+			RR->sw->requestWhois(sourceAddress);
+			return false;
+		}
+	} catch ( ... ) {
+		// Exceptions are more informatively caught in _do...() handlers but
+		// this outer try/catch will catch anything else odd.
+		TRACE("dropped ??? from %s(%s): unexpected exception in tryDecode()",sourceAddress.toString().c_str(),_remoteAddress.toString().c_str());
+		return true;
+	}
+}
+
+bool IncomingPacket::_doERROR(const RuntimeEnvironment *RR,const SharedPtr<Peer> &peer)
+{
+	try {
+		const Packet::Verb inReVerb = (Packet::Verb)(*this)[ZT_PROTO_VERB_ERROR_IDX_IN_RE_VERB];
+		const uint64_t inRePacketId = at<uint64_t>(ZT_PROTO_VERB_ERROR_IDX_IN_RE_PACKET_ID);
+		const Packet::ErrorCode errorCode = (Packet::ErrorCode)(*this)[ZT_PROTO_VERB_ERROR_IDX_ERROR_CODE];
+
+		//TRACE("ERROR %s from %s(%s) in-re %s",Packet::errorString(errorCode),peer->address().toString().c_str(),_remoteAddress.toString().c_str(),Packet::verbString(inReVerb));
+
+		switch(errorCode) {
+
+			case Packet::ERROR_OBJ_NOT_FOUND:
+				if (inReVerb == Packet::VERB_NETWORK_CONFIG_REQUEST) {
+					SharedPtr<Network> network(RR->node->network(at<uint64_t>(ZT_PROTO_VERB_ERROR_IDX_PAYLOAD)));
+					if ((network)&&(network->controller() == peer->address()))
+						network->setNotFound();
+				}
+				break;
+
+			case Packet::ERROR_UNSUPPORTED_OPERATION:
+				if (inReVerb == Packet::VERB_NETWORK_CONFIG_REQUEST) {
+					SharedPtr<Network> network(RR->node->network(at<uint64_t>(ZT_PROTO_VERB_ERROR_IDX_PAYLOAD)));
+					if ((network)&&(network->controller() == peer->address()))
+						network->setNotFound();
+				}
+				break;
+
+			case Packet::ERROR_IDENTITY_COLLISION:
+				if (RR->topology->isRoot(peer->identity()))
+					RR->node->postEvent(ZT_EVENT_FATAL_ERROR_IDENTITY_COLLISION);
+				break;
+
+			case Packet::ERROR_NEED_MEMBERSHIP_CERTIFICATE: {
+				/* Note: certificates are public so it's safe to push them to anyone
+				 * who asks. We won't communicate unless we also get a certificate
+				 * from the remote that agrees. */
+				SharedPtr<Network> network(RR->node->network(at<uint64_t>(ZT_PROTO_VERB_ERROR_IDX_PAYLOAD)));
+				if ((network)&&(network->hasConfig())&&(network->config().com)) {
+					Packet outp(peer->address(),RR->identity.address(),Packet::VERB_NETWORK_MEMBERSHIP_CERTIFICATE);
+					network->config().com.serialize(outp);
+					outp.armor(peer->key(),true);
+					RR->node->putPacket(_localAddress,_remoteAddress,outp.data(),outp.size());
+				}
+			}	break;
+
+			case Packet::ERROR_NETWORK_ACCESS_DENIED_: {
+				SharedPtr<Network> network(RR->node->network(at<uint64_t>(ZT_PROTO_VERB_ERROR_IDX_PAYLOAD)));
+				if ((network)&&(network->controller() == peer->address()))
+					network->setAccessDenied();
+			}	break;
+
+			case Packet::ERROR_UNWANTED_MULTICAST: {
+				uint64_t nwid = at<uint64_t>(ZT_PROTO_VERB_ERROR_IDX_PAYLOAD);
+				MulticastGroup mg(MAC(field(ZT_PROTO_VERB_ERROR_IDX_PAYLOAD + 8,6),6),at<uint32_t>(ZT_PROTO_VERB_ERROR_IDX_PAYLOAD + 14));
+				TRACE("%.16llx: peer %s unsubscrubed from multicast group %s",nwid,peer->address().toString().c_str(),mg.toString().c_str());
+				RR->mc->remove(nwid,mg,peer->address());
+			}	break;
+
+			default: break;
+		}
+
+		peer->received(_localAddress,_remoteAddress,hops(),packetId(),Packet::VERB_ERROR,inRePacketId,inReVerb);
+	} catch ( ... ) {
+		TRACE("dropped ERROR from %s(%s): unexpected exception",peer->address().toString().c_str(),_remoteAddress.toString().c_str());
+	}
+	return true;
+}
+
+bool IncomingPacket::_doHELLO(const RuntimeEnvironment *RR,SharedPtr<Peer> &peer)
+{
+	/* Note: this is the only packet ever sent in the clear, and it's also
+	 * the only packet that we authenticate via a different path. Authentication
+	 * occurs here and is based on the validity of the identity and the
+	 * integrity of the packet's MAC, but it must be done after we check
+	 * the identity since HELLO is a mechanism for learning new identities
+	 * in the first place. */
+
+	try {
+		const uint64_t pid = packetId();
+		const Address fromAddress(source());
+		const unsigned int protoVersion = (*this)[ZT_PROTO_VERB_HELLO_IDX_PROTOCOL_VERSION];
+		const unsigned int vMajor = (*this)[ZT_PROTO_VERB_HELLO_IDX_MAJOR_VERSION];
+		const unsigned int vMinor = (*this)[ZT_PROTO_VERB_HELLO_IDX_MINOR_VERSION];
+		const unsigned int vRevision = at<uint16_t>(ZT_PROTO_VERB_HELLO_IDX_REVISION);
+		const uint64_t timestamp = at<uint64_t>(ZT_PROTO_VERB_HELLO_IDX_TIMESTAMP);
+
+		Identity id;
+		InetAddress externalSurfaceAddress;
+		uint64_t worldId = ZT_WORLD_ID_NULL;
+		uint64_t worldTimestamp = 0;
+		{
+			unsigned int ptr = ZT_PROTO_VERB_HELLO_IDX_IDENTITY + id.deserialize(*this,ZT_PROTO_VERB_HELLO_IDX_IDENTITY);
+			if (ptr < size()) // ZeroTier One < 1.0.3 did not include physical destination address info
+				ptr += externalSurfaceAddress.deserialize(*this,ptr);
+			if ((ptr + 16) <= size()) { // older versions also did not include World IDs or timestamps
+				worldId = at<uint64_t>(ptr); ptr += 8;
+				worldTimestamp = at<uint64_t>(ptr);
+			}
+		}
+
+		if (protoVersion < ZT_PROTO_VERSION_MIN) {
+			TRACE("dropped HELLO from %s(%s): protocol version too old",id.address().toString().c_str(),_remoteAddress.toString().c_str());
+			return true;
+		}
+		if (fromAddress != id.address()) {
+			TRACE("dropped HELLO from %s(%s): identity not for sending address",fromAddress.toString().c_str(),_remoteAddress.toString().c_str());
+			return true;
+		}
+
+		if (!peer) { // peer == NULL is the normal case here
+			peer = RR->topology->getPeer(id.address());
+			if (peer) {
+				// We already have an identity with this address -- check for collisions
+
+				if (peer->identity() != id) {
+					// Identity is different from the one we already have -- address collision
+
+					unsigned char key[ZT_PEER_SECRET_KEY_LENGTH];
+					if (RR->identity.agree(id,key,ZT_PEER_SECRET_KEY_LENGTH)) {
+						if (dearmor(key)) { // ensure packet is authentic, otherwise drop
+							TRACE("rejected HELLO from %s(%s): address already claimed",id.address().toString().c_str(),_remoteAddress.toString().c_str());
+							Packet outp(id.address(),RR->identity.address(),Packet::VERB_ERROR);
+							outp.append((unsigned char)Packet::VERB_HELLO);
+							outp.append((uint64_t)pid);
+							outp.append((unsigned char)Packet::ERROR_IDENTITY_COLLISION);
+							outp.armor(key,true);
+							RR->node->putPacket(_localAddress,_remoteAddress,outp.data(),outp.size());
+						} else {
+							TRACE("rejected HELLO from %s(%s): packet failed authentication",id.address().toString().c_str(),_remoteAddress.toString().c_str());
+						}
+					} else {
+						TRACE("rejected HELLO from %s(%s): key agreement failed",id.address().toString().c_str(),_remoteAddress.toString().c_str());
+					}
+
+					return true;
+				} else {
+					// Identity is the same as the one we already have -- check packet integrity
+
+					if (!dearmor(peer->key())) {
+						TRACE("rejected HELLO from %s(%s): packet failed authentication",id.address().toString().c_str(),_remoteAddress.toString().c_str());
+						return true;
+					}
+
+					// Continue at // VALID
+				}
+			} else {
+				// We don't already have an identity with this address -- validate and learn it
+
+				// Check identity proof of work
+				if (!id.locallyValidate()) {
+					TRACE("dropped HELLO from %s(%s): identity invalid",id.address().toString().c_str(),_remoteAddress.toString().c_str());
+					return true;
+				}
+
+				// Check packet integrity and authentication
+				SharedPtr<Peer> newPeer(new Peer(RR,RR->identity,id));
+				if (!dearmor(newPeer->key())) {
+					TRACE("rejected HELLO from %s(%s): packet failed authentication",id.address().toString().c_str(),_remoteAddress.toString().c_str());
+					return true;
+				}
+				peer = RR->topology->addPeer(newPeer);
+
+				// Continue at // VALID
+			}
+
+			// VALID -- if we made it here, packet passed identity and authenticity checks!
+		}
+
+		if (externalSurfaceAddress)
+			RR->sa->iam(id.address(),_localAddress,_remoteAddress,externalSurfaceAddress,RR->topology->isRoot(id),RR->node->now());
+
+		Packet outp(id.address(),RR->identity.address(),Packet::VERB_OK);
+		outp.append((unsigned char)Packet::VERB_HELLO);
+		outp.append((uint64_t)pid);
+		outp.append((uint64_t)timestamp);
+		outp.append((unsigned char)ZT_PROTO_VERSION);
+		outp.append((unsigned char)ZEROTIER_ONE_VERSION_MAJOR);
+		outp.append((unsigned char)ZEROTIER_ONE_VERSION_MINOR);
+		outp.append((uint16_t)ZEROTIER_ONE_VERSION_REVISION);
+		if (protoVersion >= 5) {
+			_remoteAddress.serialize(outp);
+		} else {
+			/* LEGACY COMPATIBILITY HACK:
+			 *
+			 * For a while now (since 1.0.3), ZeroTier has recognized changes in
+			 * its network environment empirically by examining its external network
+			 * address as reported by trusted peers. In versions prior to 1.1.0
+			 * (protocol version < 5), they did this by saving a snapshot of this
+			 * information (in SelfAwareness.hpp) keyed by reporting device ID and
+			 * address type.
+			 *
+			 * This causes problems when clustering is combined with symmetric NAT.
+			 * Symmetric NAT remaps ports, so different endpoints in a cluster will
+			 * report back different exterior addresses. Since the old code keys
+			 * this by device ID and not sending physical address and compares the
+			 * entire address including port, it constantly thinks its external
+			 * surface is changing and resets connections when talking to a cluster.
+			 *
+			 * In new code we key by sending physical address and device and we also
+			 * take the more conservative position of only interpreting changes in
+			 * IP address (neglecting port) as a change in network topology that
+			 * necessitates a reset. But we can make older clients work here by
+			 * nulling out the port field. Since this info is only used for empirical
+			 * detection of link changes, it doesn't break anything else.
+			 */
+			InetAddress tmpa(_remoteAddress);
+			tmpa.setPort(0);
+			tmpa.serialize(outp);
+		}
+
+		if ((worldId != ZT_WORLD_ID_NULL)&&(RR->topology->worldTimestamp() > worldTimestamp)&&(worldId == RR->topology->worldId())) {
+			World w(RR->topology->world());
+			const unsigned int sizeAt = outp.size();
+			outp.addSize(2); // make room for 16-bit size field
+			w.serialize(outp,false);
+			outp.setAt<uint16_t>(sizeAt,(uint16_t)(outp.size() - (sizeAt + 2)));
+		} else {
+			outp.append((uint16_t)0); // no world update needed
+		}
+
+		outp.armor(peer->key(),true);
+		RR->node->putPacket(_localAddress,_remoteAddress,outp.data(),outp.size());
+
+		peer->setRemoteVersion(protoVersion,vMajor,vMinor,vRevision); // important for this to go first so received() knows the version
+		peer->received(_localAddress,_remoteAddress,hops(),pid,Packet::VERB_HELLO,0,Packet::VERB_NOP);
+	} catch ( ... ) {
+		TRACE("dropped HELLO from %s(%s): unexpected exception",source().toString().c_str(),_remoteAddress.toString().c_str());
+	}
+	return true;
+}
+
+bool IncomingPacket::_doOK(const RuntimeEnvironment *RR,const SharedPtr<Peer> &peer)
+{
+	try {
+		const Packet::Verb inReVerb = (Packet::Verb)(*this)[ZT_PROTO_VERB_OK_IDX_IN_RE_VERB];
+		const uint64_t inRePacketId = at<uint64_t>(ZT_PROTO_VERB_OK_IDX_IN_RE_PACKET_ID);
+
+		//TRACE("%s(%s): OK(%s)",source().toString().c_str(),_remoteAddress.toString().c_str(),Packet::verbString(inReVerb));
+
+		switch(inReVerb) {
+
+			case Packet::VERB_HELLO: {
+				const unsigned int latency = std::min((unsigned int)(RR->node->now() - at<uint64_t>(ZT_PROTO_VERB_HELLO__OK__IDX_TIMESTAMP)),(unsigned int)0xffff);
+				const unsigned int vProto = (*this)[ZT_PROTO_VERB_HELLO__OK__IDX_PROTOCOL_VERSION];
+				const unsigned int vMajor = (*this)[ZT_PROTO_VERB_HELLO__OK__IDX_MAJOR_VERSION];
+				const unsigned int vMinor = (*this)[ZT_PROTO_VERB_HELLO__OK__IDX_MINOR_VERSION];
+				const unsigned int vRevision = at<uint16_t>(ZT_PROTO_VERB_HELLO__OK__IDX_REVISION);
+
+				if (vProto < ZT_PROTO_VERSION_MIN) {
+					TRACE("%s(%s): OK(HELLO) dropped, protocol version too old",source().toString().c_str(),_remoteAddress.toString().c_str());
+					return true;
+				}
+
+				const bool trusted = RR->topology->isRoot(peer->identity());
+
+				InetAddress externalSurfaceAddress;
+				unsigned int ptr = ZT_PROTO_VERB_HELLO__OK__IDX_REVISION + 2;
+				if (ptr < size()) // ZeroTier One < 1.0.3 did not include this field
+					ptr += externalSurfaceAddress.deserialize(*this,ptr);
+				if ((trusted)&&((ptr + 2) <= size())) { // older versions also did not include this field, and right now we only use if from a root
+					World worldUpdate;
+					const unsigned int worldLen = at<uint16_t>(ptr); ptr += 2;
+					if (worldLen > 0) {
+						World w;
+						w.deserialize(*this,ptr);
+						RR->topology->worldUpdateIfValid(w);
+					}
+				}
+
+				TRACE("%s(%s): OK(HELLO), version %u.%u.%u, latency %u, reported external address %s",source().toString().c_str(),_remoteAddress.toString().c_str(),vMajor,vMinor,vRevision,latency,((externalSurfaceAddress) ? externalSurfaceAddress.toString().c_str() : "(none)"));
+
+				peer->addDirectLatencyMeasurment(latency);
+				peer->setRemoteVersion(vProto,vMajor,vMinor,vRevision);
+
+				if (externalSurfaceAddress)
+					RR->sa->iam(peer->address(),_localAddress,_remoteAddress,externalSurfaceAddress,trusted,RR->node->now());
+			}	break;
+
+			case Packet::VERB_WHOIS: {
+				if (RR->topology->isRoot(peer->identity())) {
+					const Identity id(*this,ZT_PROTO_VERB_WHOIS__OK__IDX_IDENTITY);
+					// Right now we can skip this since OK(WHOIS) is only accepted from
+					// roots. In the future it should be done if we query less trusted
+					// sources.
+					//if (id.locallyValidate())
+						RR->sw->doAnythingWaitingForPeer(RR->topology->addPeer(SharedPtr<Peer>(new Peer(RR,RR->identity,id))));
+				}
+			} break;
+
+			case Packet::VERB_NETWORK_CONFIG_REQUEST: {
+				const SharedPtr<Network> nw(RR->node->network(at<uint64_t>(ZT_PROTO_VERB_NETWORK_CONFIG_REQUEST__OK__IDX_NETWORK_ID)));
+				if ((nw)&&(nw->controller() == peer->address())) {
+					const unsigned int nclen = at<uint16_t>(ZT_PROTO_VERB_NETWORK_CONFIG_REQUEST__OK__IDX_DICT_LEN);
+					if (nclen) {
+						nw->setConfiguration(field(ZT_PROTO_VERB_NETWORK_CONFIG_REQUEST__OK__IDX_DICT,nclen),nclen,true);
+						TRACE("got network configuration for network %.16llx from %s",(unsigned long long)nw->id(),source().toString().c_str());
+					}
+				}
+			}	break;
+
+			//case Packet::VERB_ECHO: {
+			//}	break;
+
+			case Packet::VERB_MULTICAST_GATHER: {
+				const uint64_t nwid = at<uint64_t>(ZT_PROTO_VERB_MULTICAST_GATHER__OK__IDX_NETWORK_ID);
+				const MulticastGroup mg(MAC(field(ZT_PROTO_VERB_MULTICAST_GATHER__OK__IDX_MAC,6),6),at<uint32_t>(ZT_PROTO_VERB_MULTICAST_GATHER__OK__IDX_ADI));
+				TRACE("%s(%s): OK(MULTICAST_GATHER) %.16llx/%s length %u",source().toString().c_str(),_remoteAddress.toString().c_str(),nwid,mg.toString().c_str(),size());
+				const unsigned int count = at<uint16_t>(ZT_PROTO_VERB_MULTICAST_GATHER__OK__IDX_GATHER_RESULTS + 4);
+				RR->mc->addMultiple(RR->node->now(),nwid,mg,field(ZT_PROTO_VERB_MULTICAST_GATHER__OK__IDX_GATHER_RESULTS + 6,count * 5),count,at<uint32_t>(ZT_PROTO_VERB_MULTICAST_GATHER__OK__IDX_GATHER_RESULTS));
+			}	break;
+
+			case Packet::VERB_MULTICAST_FRAME: {
+				const unsigned int flags = (*this)[ZT_PROTO_VERB_MULTICAST_FRAME__OK__IDX_FLAGS];
+				const uint64_t nwid = at<uint64_t>(ZT_PROTO_VERB_MULTICAST_FRAME__OK__IDX_NETWORK_ID);
+				const MulticastGroup mg(MAC(field(ZT_PROTO_VERB_MULTICAST_FRAME__OK__IDX_MAC,6),6),at<uint32_t>(ZT_PROTO_VERB_MULTICAST_FRAME__OK__IDX_ADI));
+
+				//TRACE("%s(%s): OK(MULTICAST_FRAME) %.16llx/%s flags %.2x",peer->address().toString().c_str(),_remoteAddress.toString().c_str(),nwid,mg.toString().c_str(),flags);
+
+				unsigned int offset = 0;
+
+				if ((flags & 0x01) != 0) {
+					// OK(MULTICAST_FRAME) includes certificate of membership update
+					CertificateOfMembership com;
+					offset += com.deserialize(*this,ZT_PROTO_VERB_MULTICAST_FRAME__OK__IDX_COM_AND_GATHER_RESULTS);
+					peer->validateAndSetNetworkMembershipCertificate(nwid,com);
+				}
+
+				if ((flags & 0x02) != 0) {
+					// OK(MULTICAST_FRAME) includes implicit gather results
+					offset += ZT_PROTO_VERB_MULTICAST_FRAME__OK__IDX_COM_AND_GATHER_RESULTS;
+					unsigned int totalKnown = at<uint32_t>(offset); offset += 4;
+					unsigned int count = at<uint16_t>(offset); offset += 2;
+					RR->mc->addMultiple(RR->node->now(),nwid,mg,field(offset,count * 5),count,totalKnown);
+				}
+			}	break;
+
+			default: break;
+		}
+
+		peer->received(_localAddress,_remoteAddress,hops(),packetId(),Packet::VERB_OK,inRePacketId,inReVerb);
+	} catch ( ... ) {
+		TRACE("dropped OK from %s(%s): unexpected exception",source().toString().c_str(),_remoteAddress.toString().c_str());
+	}
+	return true;
+}
+
+bool IncomingPacket::_doWHOIS(const RuntimeEnvironment *RR,const SharedPtr<Peer> &peer)
+{
+	try {
+		if (payloadLength() == ZT_ADDRESS_LENGTH) {
+			Identity queried(RR->topology->getIdentity(Address(payload(),ZT_ADDRESS_LENGTH)));
+			if (queried) {
+				Packet outp(peer->address(),RR->identity.address(),Packet::VERB_OK);
+				outp.append((unsigned char)Packet::VERB_WHOIS);
+				outp.append(packetId());
+				queried.serialize(outp,false);
+				outp.armor(peer->key(),true);
+				RR->node->putPacket(_localAddress,_remoteAddress,outp.data(),outp.size());
+			} else {
+#ifdef ZT_ENABLE_CLUSTER
+				if (RR->cluster)
+					RR->cluster->sendDistributedQuery(*this);
+#endif
+			}
+		} else {
+			TRACE("dropped WHOIS from %s(%s): missing or invalid address",source().toString().c_str(),_remoteAddress.toString().c_str());
+		}
+		peer->received(_localAddress,_remoteAddress,hops(),packetId(),Packet::VERB_WHOIS,0,Packet::VERB_NOP);
+	} catch ( ... ) {
+		TRACE("dropped WHOIS from %s(%s): unexpected exception",source().toString().c_str(),_remoteAddress.toString().c_str());
+	}
+	return true;
+}
+
+bool IncomingPacket::_doRENDEZVOUS(const RuntimeEnvironment *RR,const SharedPtr<Peer> &peer)
+{
+	try {
+		if (RR->topology->isUpstream(peer->identity())) {
+			const Address with(field(ZT_PROTO_VERB_RENDEZVOUS_IDX_ZTADDRESS,ZT_ADDRESS_LENGTH),ZT_ADDRESS_LENGTH);
+			const SharedPtr<Peer> withPeer(RR->topology->getPeer(with));
+			if (withPeer) {
+				const unsigned int port = at<uint16_t>(ZT_PROTO_VERB_RENDEZVOUS_IDX_PORT);
+				const unsigned int addrlen = (*this)[ZT_PROTO_VERB_RENDEZVOUS_IDX_ADDRLEN];
+				if ((port > 0)&&((addrlen == 4)||(addrlen == 16))) {
+					peer->received(_localAddress,_remoteAddress,hops(),packetId(),Packet::VERB_RENDEZVOUS,0,Packet::VERB_NOP);
+
+					InetAddress atAddr(field(ZT_PROTO_VERB_RENDEZVOUS_IDX_ADDRESS,addrlen),addrlen,port);
+					TRACE("RENDEZVOUS from %s says %s might be at %s, starting NAT-t",peer->address().toString().c_str(),with.toString().c_str(),atAddr.toString().c_str());
+					if (RR->node->shouldUsePathForZeroTierTraffic(_localAddress,atAddr))
+						RR->sw->rendezvous(withPeer,_localAddress,atAddr);
+				} else {
+					TRACE("dropped corrupt RENDEZVOUS from %s(%s) (bad address or port)",peer->address().toString().c_str(),_remoteAddress.toString().c_str());
+				}
+			} else {
+				RR->sw->requestWhois(with);
+				TRACE("ignored RENDEZVOUS from %s(%s) to meet unknown peer %s",peer->address().toString().c_str(),_remoteAddress.toString().c_str(),with.toString().c_str());
+			}
+		} else {
+			TRACE("ignored RENDEZVOUS from %s(%s): not a root server or a network relay",peer->address().toString().c_str(),_remoteAddress.toString().c_str());
+		}
+	} catch ( ... ) {
+		TRACE("dropped RENDEZVOUS from %s(%s): unexpected exception",peer->address().toString().c_str(),_remoteAddress.toString().c_str());
+	}
+	return true;
+}
+
+bool IncomingPacket::_doFRAME(const RuntimeEnvironment *RR,const SharedPtr<Peer> &peer)
+{
+	try {
+		const SharedPtr<Network> network(RR->node->network(at<uint64_t>(ZT_PROTO_VERB_FRAME_IDX_NETWORK_ID)));
+		if (network) {
+			if (size() > ZT_PROTO_VERB_FRAME_IDX_PAYLOAD) {
+				if (!network->isAllowed(peer)) {
+					TRACE("dropped FRAME from %s(%s): not a member of private network %.16llx",peer->address().toString().c_str(),_remoteAddress.toString().c_str(),(unsigned long long)network->id());
+					_sendErrorNeedCertificate(RR,peer,network->id());
+					return true;
+				}
+
+				const unsigned int etherType = at<uint16_t>(ZT_PROTO_VERB_FRAME_IDX_ETHERTYPE);
+				if (!network->config().permitsEtherType(etherType)) {
+					TRACE("dropped FRAME from %s(%s): ethertype %.4x not allowed on %.16llx",peer->address().toString().c_str(),_remoteAddress.toString().c_str(),(unsigned int)etherType,(unsigned long long)network->id());
+					return true;
+				}
+
+				const unsigned int payloadLen = size() - ZT_PROTO_VERB_FRAME_IDX_PAYLOAD;
+				RR->node->putFrame(network->id(),network->userPtr(),MAC(peer->address(),network->id()),network->mac(),etherType,0,field(ZT_PROTO_VERB_FRAME_IDX_PAYLOAD,payloadLen),payloadLen);
+			}
+
+			peer->received(_localAddress,_remoteAddress,hops(),packetId(),Packet::VERB_FRAME,0,Packet::VERB_NOP);
+		} else {
+			TRACE("dropped FRAME from %s(%s): we are not connected to network %.16llx",source().toString().c_str(),_remoteAddress.toString().c_str(),at<uint64_t>(ZT_PROTO_VERB_FRAME_IDX_NETWORK_ID));
+		}
+	} catch ( ... ) {
+		TRACE("dropped FRAME from %s(%s): unexpected exception",source().toString().c_str(),_remoteAddress.toString().c_str());
+	}
+	return true;
+}
+
+bool IncomingPacket::_doEXT_FRAME(const RuntimeEnvironment *RR,const SharedPtr<Peer> &peer)
+{
+	try {
+		SharedPtr<Network> network(RR->node->network(at<uint64_t>(ZT_PROTO_VERB_EXT_FRAME_IDX_NETWORK_ID)));
+		if (network) {
+			if (size() > ZT_PROTO_VERB_EXT_FRAME_IDX_PAYLOAD) {
+				const unsigned int flags = (*this)[ZT_PROTO_VERB_EXT_FRAME_IDX_FLAGS];
+
+				unsigned int comLen = 0;
+				if ((flags & 0x01) != 0) {
+					CertificateOfMembership com;
+					comLen = com.deserialize(*this,ZT_PROTO_VERB_EXT_FRAME_IDX_COM);
+					peer->validateAndSetNetworkMembershipCertificate(network->id(),com);
+				}
+
+				if (!network->isAllowed(peer)) {
+					TRACE("dropped EXT_FRAME from %s(%s): not a member of private network %.16llx",peer->address().toString().c_str(),_remoteAddress.toString().c_str(),network->id());
+					_sendErrorNeedCertificate(RR,peer,network->id());
+					return true;
+				}
+
+				// Everything after flags must be adjusted based on the length
+				// of the certificate, if there was one...
+
+				const unsigned int etherType = at<uint16_t>(comLen + ZT_PROTO_VERB_EXT_FRAME_IDX_ETHERTYPE);
+				if (!network->config().permitsEtherType(etherType)) {
+					TRACE("dropped EXT_FRAME from %s(%s): ethertype %.4x not allowed on network %.16llx",peer->address().toString().c_str(),_remoteAddress.toString().c_str(),(unsigned int)etherType,(unsigned long long)network->id());
+					return true;
+				}
+
+				const MAC to(field(comLen + ZT_PROTO_VERB_EXT_FRAME_IDX_TO,ZT_PROTO_VERB_EXT_FRAME_LEN_TO),ZT_PROTO_VERB_EXT_FRAME_LEN_TO);
+				const MAC from(field(comLen + ZT_PROTO_VERB_EXT_FRAME_IDX_FROM,ZT_PROTO_VERB_EXT_FRAME_LEN_FROM),ZT_PROTO_VERB_EXT_FRAME_LEN_FROM);
+
+				if (to.isMulticast()) {
+					TRACE("dropped EXT_FRAME from %s@%s(%s) to %s: destination is multicast, must use MULTICAST_FRAME",from.toString().c_str(),peer->address().toString().c_str(),_remoteAddress.toString().c_str(),to.toString().c_str());
+					return true;
+				}
+
+				if ((!from)||(from.isMulticast())||(from == network->mac())) {
+					TRACE("dropped EXT_FRAME from %s@%s(%s) to %s: invalid source MAC",from.toString().c_str(),peer->address().toString().c_str(),_remoteAddress.toString().c_str(),to.toString().c_str());
+					return true;
+				}
+
+				if (from != MAC(peer->address(),network->id())) {
+					if (network->config().permitsBridging(peer->address())) {
+						network->learnBridgeRoute(from,peer->address());
+					} else {
+						TRACE("dropped EXT_FRAME from %s@%s(%s) to %s: sender not allowed to bridge into %.16llx",from.toString().c_str(),peer->address().toString().c_str(),_remoteAddress.toString().c_str(),to.toString().c_str(),network->id());
+						return true;
+					}
+				} else if (to != network->mac()) {
+					if (!network->config().permitsBridging(RR->identity.address())) {
+						TRACE("dropped EXT_FRAME from %s@%s(%s) to %s: I cannot bridge to %.16llx or bridging disabled on network",from.toString().c_str(),peer->address().toString().c_str(),_remoteAddress.toString().c_str(),to.toString().c_str(),network->id());
+						return true;
+					}
+				}
+
+				const unsigned int payloadLen = size() - (comLen + ZT_PROTO_VERB_EXT_FRAME_IDX_PAYLOAD);
+				RR->node->putFrame(network->id(),network->userPtr(),from,to,etherType,0,field(comLen + ZT_PROTO_VERB_EXT_FRAME_IDX_PAYLOAD,payloadLen),payloadLen);
+			}
+
+			peer->received(_localAddress,_remoteAddress,hops(),packetId(),Packet::VERB_EXT_FRAME,0,Packet::VERB_NOP);
+		} else {
+			TRACE("dropped EXT_FRAME from %s(%s): we are not connected to network %.16llx",source().toString().c_str(),_remoteAddress.toString().c_str(),at<uint64_t>(ZT_PROTO_VERB_FRAME_IDX_NETWORK_ID));
+		}
+	} catch ( ... ) {
+		TRACE("dropped EXT_FRAME from %s(%s): unexpected exception",source().toString().c_str(),_remoteAddress.toString().c_str());
+	}
+	return true;
+}
+
+bool IncomingPacket::_doECHO(const RuntimeEnvironment *RR,const SharedPtr<Peer> &peer)
+{
+	try {
+		const uint64_t pid = packetId();
+		Packet outp(peer->address(),RR->identity.address(),Packet::VERB_OK);
+		outp.append((unsigned char)Packet::VERB_ECHO);
+		outp.append((uint64_t)pid);
+		if (size() > ZT_PACKET_IDX_PAYLOAD)
+			outp.append(reinterpret_cast<const unsigned char *>(data()) + ZT_PACKET_IDX_PAYLOAD,size() - ZT_PACKET_IDX_PAYLOAD);
+		outp.armor(peer->key(),true);
+		RR->node->putPacket(_localAddress,_remoteAddress,outp.data(),outp.size());
+		peer->received(_localAddress,_remoteAddress,hops(),pid,Packet::VERB_ECHO,0,Packet::VERB_NOP);
+	} catch ( ... ) {
+		TRACE("dropped ECHO from %s(%s): unexpected exception",source().toString().c_str(),_remoteAddress.toString().c_str());
+	}
+	return true;
+}
+
+bool IncomingPacket::_doMULTICAST_LIKE(const RuntimeEnvironment *RR,const SharedPtr<Peer> &peer)
+{
+	try {
+		const uint64_t now = RR->node->now();
+
+		// Iterate through 18-byte network,MAC,ADI tuples
+		for(unsigned int ptr=ZT_PACKET_IDX_PAYLOAD;ptr<size();ptr+=18) {
+			const uint64_t nwid = at<uint64_t>(ptr);
+			const MulticastGroup group(MAC(field(ptr + 8,6),6),at<uint32_t>(ptr + 14));
+			RR->mc->add(now,nwid,group,peer->address());
+		}
+
+		peer->received(_localAddress,_remoteAddress,hops(),packetId(),Packet::VERB_MULTICAST_LIKE,0,Packet::VERB_NOP);
+	} catch ( ... ) {
+		TRACE("dropped MULTICAST_LIKE from %s(%s): unexpected exception",source().toString().c_str(),_remoteAddress.toString().c_str());
+	}
+	return true;
+}
+
+bool IncomingPacket::_doNETWORK_MEMBERSHIP_CERTIFICATE(const RuntimeEnvironment *RR,const SharedPtr<Peer> &peer)
+{
+	try {
+		CertificateOfMembership com;
+
+		unsigned int ptr = ZT_PACKET_IDX_PAYLOAD;
+		while (ptr < size()) {
+			ptr += com.deserialize(*this,ptr);
+			peer->validateAndSetNetworkMembershipCertificate(com.networkId(),com);
+		}
+
+		peer->received(_localAddress,_remoteAddress,hops(),packetId(),Packet::VERB_NETWORK_MEMBERSHIP_CERTIFICATE,0,Packet::VERB_NOP);
+	} catch ( ... ) {
+		TRACE("dropped NETWORK_MEMBERSHIP_CERTIFICATE from %s(%s): unexpected exception",source().toString().c_str(),_remoteAddress.toString().c_str());
+	}
+	return true;
+}
+
+bool IncomingPacket::_doNETWORK_CONFIG_REQUEST(const RuntimeEnvironment *RR,const SharedPtr<Peer> &peer)
+{
+	try {
+		const uint64_t nwid = at<uint64_t>(ZT_PROTO_VERB_NETWORK_CONFIG_REQUEST_IDX_NETWORK_ID);
+
+		const unsigned int metaDataLength = at<uint16_t>(ZT_PROTO_VERB_NETWORK_CONFIG_REQUEST_IDX_DICT_LEN);
+		const uint8_t *metaDataBytes = (const uint8_t *)field(ZT_PROTO_VERB_NETWORK_CONFIG_REQUEST_IDX_DICT,metaDataLength);
+
+		NetworkConfigRequestMetaData metaData;
+		bool haveNewStyleMetaData = false;
+		for(unsigned int i=0;i<metaDataLength;++i) {
+			if ((metaDataBytes[i] == 0)&&(i < (metaDataLength - 2))) {
+				haveNewStyleMetaData = true;
+				break;
+			}
+		}
+		if (haveNewStyleMetaData) {
+			Buffer<4096> md(metaDataBytes,metaDataLength);
+			metaData.deserialize(md,0); // the meta-data deserializer automatically skips old-style meta-data
+		} else {
+#ifdef ZT_SUPPORT_OLD_STYLE_NETCONF
+			const Dictionary oldStyleMetaData((const char *)metaDataBytes,metaDataLength);
+			metaData.majorVersion = (unsigned int)oldStyleMetaData.getHexUInt(ZT_NETWORKCONFIG_REQUEST_METADATA_KEY_NODE_MAJOR_VERSION,0);
+			metaData.minorVersion = (unsigned int)oldStyleMetaData.getHexUInt(ZT_NETWORKCONFIG_REQUEST_METADATA_KEY_NODE_MINOR_VERSION,0);
+			metaData.revision = (unsigned int)oldStyleMetaData.getHexUInt(ZT_NETWORKCONFIG_REQUEST_METADATA_KEY_NODE_REVISION,0);
+#endif
+		}
+
+		//const uint64_t haveRevision = ((ZT_PROTO_VERB_NETWORK_CONFIG_REQUEST_IDX_DICT + metaDataLength + 8) <= size()) ? at<uint64_t>(ZT_PROTO_VERB_NETWORK_CONFIG_REQUEST_IDX_DICT + metaDataLength) : 0ULL;
+
+		const unsigned int h = hops();
+		const uint64_t pid = packetId();
+		peer->received(_localAddress,_remoteAddress,h,pid,Packet::VERB_NETWORK_CONFIG_REQUEST,0,Packet::VERB_NOP);
+
+		if (RR->localNetworkController) {
+			Buffer<8194> netconf;
+			switch(RR->localNetworkController->doNetworkConfigRequest((h > 0) ? InetAddress() : _remoteAddress,RR->identity,peer->identity(),nwid,metaData,netconf)) {
+
+				case NetworkController::NETCONF_QUERY_OK: {
+					Packet outp(peer->address(),RR->identity.address(),Packet::VERB_OK);
+					outp.append((unsigned char)Packet::VERB_NETWORK_CONFIG_REQUEST);
+					outp.append(pid);
+					outp.append(nwid);
+					outp.append((uint16_t)netconf.size());
+					outp.append(netconf.data(),(unsigned int)netconf.size());
+					outp.compress();
+					outp.armor(peer->key(),true);
+					if (outp.size() > ZT_PROTO_MAX_PACKET_LENGTH) { // sanity check
+						//TRACE("NETWORK_CONFIG_REQUEST failed: internal error: netconf size %u is too large",(unsigned int)netconfStr.length());
+					} else {
+						RR->node->putPacket(_localAddress,_remoteAddress,outp.data(),outp.size());
+					}
+				}	break;
+
+				case NetworkController::NETCONF_QUERY_OBJECT_NOT_FOUND: {
+					Packet outp(peer->address(),RR->identity.address(),Packet::VERB_ERROR);
+					outp.append((unsigned char)Packet::VERB_NETWORK_CONFIG_REQUEST);
+					outp.append(pid);
+					outp.append((unsigned char)Packet::ERROR_OBJ_NOT_FOUND);
+					outp.append(nwid);
+					outp.armor(peer->key(),true);
+					RR->node->putPacket(_localAddress,_remoteAddress,outp.data(),outp.size());
+				}	break;
+
+				case NetworkController::NETCONF_QUERY_ACCESS_DENIED: {
+					Packet outp(peer->address(),RR->identity.address(),Packet::VERB_ERROR);
+					outp.append((unsigned char)Packet::VERB_NETWORK_CONFIG_REQUEST);
+					outp.append(pid);
+					outp.append((unsigned char)Packet::ERROR_NETWORK_ACCESS_DENIED_);
+					outp.append(nwid);
+					outp.armor(peer->key(),true);
+					RR->node->putPacket(_localAddress,_remoteAddress,outp.data(),outp.size());
+				} break;
+
+				case NetworkController::NETCONF_QUERY_INTERNAL_SERVER_ERROR:
+					// TRACE("NETWORK_CONFIG_REQUEST failed: internal error: %s",netconf.get("error","(unknown)").c_str());
+					break;
+
+				case NetworkController::NETCONF_QUERY_IGNORE:
+					break;
+
+				default:
+					TRACE("NETWORK_CONFIG_REQUEST failed: invalid return value from NetworkController::doNetworkConfigRequest()");
+					break;
+
+			}
+		} else {
+			Packet outp(peer->address(),RR->identity.address(),Packet::VERB_ERROR);
+			outp.append((unsigned char)Packet::VERB_NETWORK_CONFIG_REQUEST);
+			outp.append(pid);
+			outp.append((unsigned char)Packet::ERROR_UNSUPPORTED_OPERATION);
+			outp.append(nwid);
+			outp.armor(peer->key(),true);
+			RR->node->putPacket(_localAddress,_remoteAddress,outp.data(),outp.size());
+		}
+	} catch ( ... ) {
+		TRACE("dropped NETWORK_CONFIG_REQUEST from %s(%s): unexpected exception",source().toString().c_str(),_remoteAddress.toString().c_str());
+	}
+	return true;
+}
+
+bool IncomingPacket::_doNETWORK_CONFIG_REFRESH(const RuntimeEnvironment *RR,const SharedPtr<Peer> &peer)
+{
+	try {
+		unsigned int ptr = ZT_PACKET_IDX_PAYLOAD;
+		while ((ptr + 8) <= size()) {
+			uint64_t nwid = at<uint64_t>(ptr);
+			SharedPtr<Network> nw(RR->node->network(nwid));
+			if ((nw)&&(peer->address() == nw->controller()))
+				nw->requestConfiguration();
+			ptr += 8;
+		}
+		peer->received(_localAddress,_remoteAddress,hops(),packetId(),Packet::VERB_NETWORK_CONFIG_REFRESH,0,Packet::VERB_NOP);
+	} catch ( ... ) {
+		TRACE("dropped NETWORK_CONFIG_REFRESH from %s(%s): unexpected exception",source().toString().c_str(),_remoteAddress.toString().c_str());
+	}
+	return true;
+}
+
+bool IncomingPacket::_doMULTICAST_GATHER(const RuntimeEnvironment *RR,const SharedPtr<Peer> &peer)
+{
+	try {
+		const uint64_t nwid = at<uint64_t>(ZT_PROTO_VERB_MULTICAST_GATHER_IDX_NETWORK_ID);
+		const MulticastGroup mg(MAC(field(ZT_PROTO_VERB_MULTICAST_GATHER_IDX_MAC,6),6),at<uint32_t>(ZT_PROTO_VERB_MULTICAST_GATHER_IDX_ADI));
+		const unsigned int gatherLimit = at<uint32_t>(ZT_PROTO_VERB_MULTICAST_GATHER_IDX_GATHER_LIMIT);
+
+		//TRACE("<<MC %s(%s) GATHER up to %u in %.16llx/%s",source().toString().c_str(),_remoteAddress.toString().c_str(),gatherLimit,nwid,mg.toString().c_str());
+
+		if (gatherLimit) {
+			Packet outp(peer->address(),RR->identity.address(),Packet::VERB_OK);
+			outp.append((unsigned char)Packet::VERB_MULTICAST_GATHER);
+			outp.append(packetId());
+			outp.append(nwid);
+			mg.mac().appendTo(outp);
+			outp.append((uint32_t)mg.adi());
+			const unsigned int gatheredLocally = RR->mc->gather(peer->address(),nwid,mg,outp,gatherLimit);
+			if (gatheredLocally) {
+				outp.armor(peer->key(),true);
+				RR->node->putPacket(_localAddress,_remoteAddress,outp.data(),outp.size());
+			}
+
+#ifdef ZT_ENABLE_CLUSTER
+			if ((RR->cluster)&&(gatheredLocally < gatherLimit))
+				RR->cluster->sendDistributedQuery(*this);
+#endif
+		}
+
+		peer->received(_localAddress,_remoteAddress,hops(),packetId(),Packet::VERB_MULTICAST_GATHER,0,Packet::VERB_NOP);
+	} catch ( ... ) {
+		TRACE("dropped MULTICAST_GATHER from %s(%s): unexpected exception",source().toString().c_str(),_remoteAddress.toString().c_str());
+	}
+	return true;
+}
+
+bool IncomingPacket::_doMULTICAST_FRAME(const RuntimeEnvironment *RR,const SharedPtr<Peer> &peer)
+{
+	try {
+		const uint64_t nwid = at<uint64_t>(ZT_PROTO_VERB_MULTICAST_FRAME_IDX_NETWORK_ID);
+		const unsigned int flags = (*this)[ZT_PROTO_VERB_MULTICAST_FRAME_IDX_FLAGS];
+
+		const SharedPtr<Network> network(RR->node->network(nwid));
+		if (network) {
+			// Offset -- size of optional fields added to position of later fields
+			unsigned int offset = 0;
+
+			if ((flags & 0x01) != 0) {
+				CertificateOfMembership com;
+				offset += com.deserialize(*this,ZT_PROTO_VERB_MULTICAST_FRAME_IDX_COM);
+				peer->validateAndSetNetworkMembershipCertificate(nwid,com);
+			}
+
+			// Check membership after we've read any included COM, since
+			// that cert might be what we needed.
+			if (!network->isAllowed(peer)) {
+				TRACE("dropped MULTICAST_FRAME from %s(%s): not a member of private network %.16llx",peer->address().toString().c_str(),_remoteAddress.toString().c_str(),(unsigned long long)network->id());
+				_sendErrorNeedCertificate(RR,peer,network->id());
+				return true;
+			}
+
+			unsigned int gatherLimit = 0;
+			if ((flags & 0x02) != 0) {
+				gatherLimit = at<uint32_t>(offset + ZT_PROTO_VERB_MULTICAST_FRAME_IDX_GATHER_LIMIT);
+				offset += 4;
+			}
+
+			MAC from;
+			if ((flags & 0x04) != 0) {
+				from.setTo(field(offset + ZT_PROTO_VERB_MULTICAST_FRAME_IDX_SOURCE_MAC,6),6);
+				offset += 6;
+			} else {
+				from.fromAddress(peer->address(),nwid);
+			}
+
+			const MulticastGroup to(MAC(field(offset + ZT_PROTO_VERB_MULTICAST_FRAME_IDX_DEST_MAC,6),6),at<uint32_t>(offset + ZT_PROTO_VERB_MULTICAST_FRAME_IDX_DEST_ADI));
+			const unsigned int etherType = at<uint16_t>(offset + ZT_PROTO_VERB_MULTICAST_FRAME_IDX_ETHERTYPE);
+			const unsigned int payloadLen = size() - (offset + ZT_PROTO_VERB_MULTICAST_FRAME_IDX_FRAME);
+
+			//TRACE("<<MC FRAME %.16llx/%s from %s@%s flags %.2x length %u",nwid,to.toString().c_str(),from.toString().c_str(),peer->address().toString().c_str(),flags,payloadLen);
+
+			if ((payloadLen > 0)&&(payloadLen <= ZT_IF_MTU)) {
+				if (!to.mac().isMulticast()) {
+					TRACE("dropped MULTICAST_FRAME from %s@%s(%s) to %s: destination is unicast, must use FRAME or EXT_FRAME",from.toString().c_str(),peer->address().toString().c_str(),_remoteAddress.toString().c_str(),to.toString().c_str());
+					return true;
+				}
+				if ((!from)||(from.isMulticast())||(from == network->mac())) {
+					TRACE("dropped MULTICAST_FRAME from %s@%s(%s) to %s: invalid source MAC",from.toString().c_str(),peer->address().toString().c_str(),_remoteAddress.toString().c_str(),to.toString().c_str());
+					return true;
+				}
+
+				if (from != MAC(peer->address(),network->id())) {
+					if (network->config().permitsBridging(peer->address())) {
+						network->learnBridgeRoute(from,peer->address());
+					} else {
+						TRACE("dropped MULTICAST_FRAME from %s@%s(%s) to %s: sender not allowed to bridge into %.16llx",from.toString().c_str(),peer->address().toString().c_str(),_remoteAddress.toString().c_str(),to.toString().c_str(),network->id());
+						return true;
+					}
+				}
+
+				RR->node->putFrame(network->id(),network->userPtr(),from,to.mac(),etherType,0,field(offset + ZT_PROTO_VERB_MULTICAST_FRAME_IDX_FRAME,payloadLen),payloadLen);
+			}
+
+			if (gatherLimit) {
+				Packet outp(source(),RR->identity.address(),Packet::VERB_OK);
+				outp.append((unsigned char)Packet::VERB_MULTICAST_FRAME);
+				outp.append(packetId());
+				outp.append(nwid);
+				to.mac().appendTo(outp);
+				outp.append((uint32_t)to.adi());
+				outp.append((unsigned char)0x02); // flag 0x02 = contains gather results
+				if (RR->mc->gather(peer->address(),nwid,to,outp,gatherLimit)) {
+					outp.armor(peer->key(),true);
+					RR->node->putPacket(_localAddress,_remoteAddress,outp.data(),outp.size());
+				}
+			}
+		} // else ignore -- not a member of this network
+
+		peer->received(_localAddress,_remoteAddress,hops(),packetId(),Packet::VERB_MULTICAST_FRAME,0,Packet::VERB_NOP);
+	} catch ( ... ) {
+		TRACE("dropped MULTICAST_FRAME from %s(%s): unexpected exception",source().toString().c_str(),_remoteAddress.toString().c_str());
+	}
+	return true;
+}
+
+bool IncomingPacket::_doPUSH_DIRECT_PATHS(const RuntimeEnvironment *RR,const SharedPtr<Peer> &peer)
+{
+	try {
+		const uint64_t now = RR->node->now();
+
+		// First, subject this to a rate limit
+		if (!peer->shouldRespondToDirectPathPush(now)) {
+			TRACE("dropped PUSH_DIRECT_PATHS from %s(%s): circuit breaker tripped",source().toString().c_str(),_remoteAddress.toString().c_str());
+			return true;
+		}
+
+		// Second, limit addresses by scope and type
+		uint8_t countPerScope[ZT_INETADDRESS_MAX_SCOPE+1][2]; // [][0] is v4, [][1] is v6
+		memset(countPerScope,0,sizeof(countPerScope));
+
+		unsigned int count = at<uint16_t>(ZT_PACKET_IDX_PAYLOAD);
+		unsigned int ptr = ZT_PACKET_IDX_PAYLOAD + 2;
+
+		while (count--) { // if ptr overflows Buffer will throw
+			// TODO: some flags are not yet implemented
+
+			unsigned int flags = (*this)[ptr++];
+			unsigned int extLen = at<uint16_t>(ptr); ptr += 2;
+			ptr += extLen; // unused right now
+			unsigned int addrType = (*this)[ptr++];
+			unsigned int addrLen = (*this)[ptr++];
+
+			switch(addrType) {
+				case 4: {
+					InetAddress a(field(ptr,4),4,at<uint16_t>(ptr + 4));
+
+					bool redundant = false;
+					if ((flags & ZT_PUSH_DIRECT_PATHS_FLAG_CLUSTER_REDIRECT) != 0) {
+						peer->setClusterOptimalPathForAddressFamily(a);
+					} else {
+						redundant = peer->hasActivePathTo(now,a);
+					}
+
+					if ( ((flags & ZT_PUSH_DIRECT_PATHS_FLAG_FORGET_PATH) == 0) && (!redundant) && (RR->node->shouldUsePathForZeroTierTraffic(_localAddress,a)) ) {
+						if (++countPerScope[(int)a.ipScope()][0] <= ZT_PUSH_DIRECT_PATHS_MAX_PER_SCOPE_AND_FAMILY) {
+							TRACE("attempting to contact %s at pushed direct path %s",peer->address().toString().c_str(),a.toString().c_str());
+							peer->sendHELLO(InetAddress(),a,now);
+						} else {
+							TRACE("ignoring contact for %s at %s -- too many per scope",peer->address().toString().c_str(),a.toString().c_str());
+						}
+					}
+				}	break;
+				case 6: {
+					InetAddress a(field(ptr,16),16,at<uint16_t>(ptr + 16));
+
+					bool redundant = false;
+					if ((flags & ZT_PUSH_DIRECT_PATHS_FLAG_CLUSTER_REDIRECT) != 0) {
+						peer->setClusterOptimalPathForAddressFamily(a);
+					} else {
+						redundant = peer->hasActivePathTo(now,a);
+					}
+
+					if ( ((flags & ZT_PUSH_DIRECT_PATHS_FLAG_FORGET_PATH) == 0) && (!redundant) && (RR->node->shouldUsePathForZeroTierTraffic(_localAddress,a)) ) {
+						if (++countPerScope[(int)a.ipScope()][1] <= ZT_PUSH_DIRECT_PATHS_MAX_PER_SCOPE_AND_FAMILY) {
+							TRACE("attempting to contact %s at pushed direct path %s",peer->address().toString().c_str(),a.toString().c_str());
+							peer->sendHELLO(InetAddress(),a,now);
+						} else {
+							TRACE("ignoring contact for %s at %s -- too many per scope",peer->address().toString().c_str(),a.toString().c_str());
+						}
+					}
+				}	break;
+			}
+			ptr += addrLen;
+		}
+
+		peer->received(_localAddress,_remoteAddress,hops(),packetId(),Packet::VERB_PUSH_DIRECT_PATHS,0,Packet::VERB_NOP);
+	} catch ( ... ) {
+		TRACE("dropped PUSH_DIRECT_PATHS from %s(%s): unexpected exception",source().toString().c_str(),_remoteAddress.toString().c_str());
+	}
+	return true;
+}
+
+bool IncomingPacket::_doCIRCUIT_TEST(const RuntimeEnvironment *RR,const SharedPtr<Peer> &peer)
+{
+	try {
+		const Address originatorAddress(field(ZT_PACKET_IDX_PAYLOAD,ZT_ADDRESS_LENGTH),ZT_ADDRESS_LENGTH);
+		SharedPtr<Peer> originator(RR->topology->getPeer(originatorAddress));
+		if (!originator) {
+			RR->sw->requestWhois(originatorAddress);
+			return false;
+		}
+
+		const unsigned int flags = at<uint16_t>(ZT_PACKET_IDX_PAYLOAD + 5);
+		const uint64_t timestamp = at<uint64_t>(ZT_PACKET_IDX_PAYLOAD + 7);
+		const uint64_t testId = at<uint64_t>(ZT_PACKET_IDX_PAYLOAD + 15);
+
+		// Tracks total length of variable length fields, initialized to originator credential length below
+		unsigned int vlf;
+
+		// Originator credentials
+		const unsigned int originatorCredentialLength = vlf = at<uint16_t>(ZT_PACKET_IDX_PAYLOAD + 23);
+		uint64_t originatorCredentialNetworkId = 0;
+		if (originatorCredentialLength >= 1) {
+			switch((*this)[ZT_PACKET_IDX_PAYLOAD + 25]) {
+				case 0x01: { // 64-bit network ID, originator must be controller
+					if (originatorCredentialLength >= 9)
+						originatorCredentialNetworkId = at<uint64_t>(ZT_PACKET_IDX_PAYLOAD + 26);
+				}	break;
+				default: break;
+			}
+		}
+
+		// Add length of "additional fields," which are currently unused
+		vlf += at<uint16_t>(ZT_PACKET_IDX_PAYLOAD + 25 + vlf);
+
+		// Verify signature -- only tests signed by their originators are allowed
+		const unsigned int signatureLength = at<uint16_t>(ZT_PACKET_IDX_PAYLOAD + 27 + vlf);
+		if (!originator->identity().verify(field(ZT_PACKET_IDX_PAYLOAD,27 + vlf),27 + vlf,field(ZT_PACKET_IDX_PAYLOAD + 29 + vlf,signatureLength),signatureLength)) {
+			TRACE("dropped CIRCUIT_TEST from %s(%s): signature by originator %s invalid",source().toString().c_str(),_remoteAddress.toString().c_str(),originatorAddress.toString().c_str());
+			return true;
+		}
+		vlf += signatureLength;
+
+		// Save this length so we can copy the immutable parts of this test
+		// into the one we send along to next hops.
+		const unsigned int lengthOfSignedPortionAndSignature = 29 + vlf;
+
+		// Get previous hop's credential, if any
+		const unsigned int previousHopCredentialLength = at<uint16_t>(ZT_PACKET_IDX_PAYLOAD + 29 + vlf);
+		CertificateOfMembership previousHopCom;
+		if (previousHopCredentialLength >= 1) {
+			switch((*this)[ZT_PACKET_IDX_PAYLOAD + 31 + vlf]) {
+				case 0x01: { // network certificate of membership for previous hop
+					const unsigned int phcl = previousHopCom.deserialize(*this,ZT_PACKET_IDX_PAYLOAD + 32 + vlf);
+					if (phcl != (previousHopCredentialLength - 1)) {
+						TRACE("dropped CIRCUIT_TEST from %s(%s): previous hop COM invalid (%u != %u)",source().toString().c_str(),_remoteAddress.toString().c_str(),phcl,(previousHopCredentialLength - 1));
+						return true;
+					}
+				}	break;
+				default: break;
+			}
+		}
+		vlf += previousHopCredentialLength;
+
+		// Check credentials (signature already verified)
+		NetworkConfig originatorCredentialNetworkConfig;
+		if (originatorCredentialNetworkId) {
+			if (Network::controllerFor(originatorCredentialNetworkId) == originatorAddress) {
+				SharedPtr<Network> nw(RR->node->network(originatorCredentialNetworkId));
+				if ((nw)&&(nw->hasConfig())) {
+					originatorCredentialNetworkConfig = nw->config();
+					if ( ( (originatorCredentialNetworkConfig.isPublic()) || (peer->address() == originatorAddress) || ((originatorCredentialNetworkConfig.com)&&(previousHopCom)&&(originatorCredentialNetworkConfig.com.agreesWith(previousHopCom))) ) ) {
+						TRACE("CIRCUIT_TEST %.16llx received from hop %s(%s) and originator %s with valid network ID credential %.16llx (verified from originator and next hop)",testId,source().toString().c_str(),_remoteAddress.toString().c_str(),originatorAddress.toString().c_str(),originatorCredentialNetworkId);
+					} else {
+						TRACE("dropped CIRCUIT_TEST from %s(%s): originator %s specified network ID %.16llx as credential, and previous hop %s did not supply a valid COM",source().toString().c_str(),_remoteAddress.toString().c_str(),originatorAddress.toString().c_str(),originatorCredentialNetworkId,peer->address().toString().c_str());
+						return true;
+					}
+				} else {
+					TRACE("dropped CIRCUIT_TEST from %s(%s): originator %s specified network ID %.16llx as credential, and we are not a member",source().toString().c_str(),_remoteAddress.toString().c_str(),originatorAddress.toString().c_str(),originatorCredentialNetworkId);
+					return true;
+				}
+			} else {
+				TRACE("dropped CIRCUIT_TEST from %s(%s): originator %s specified network ID as credential, is not controller for %.16llx",source().toString().c_str(),_remoteAddress.toString().c_str(),originatorAddress.toString().c_str(),originatorCredentialNetworkId);
+				return true;
+			}
+		} else {
+			TRACE("dropped CIRCUIT_TEST from %s(%s): originator %s did not specify a credential or credential type",source().toString().c_str(),_remoteAddress.toString().c_str(),originatorAddress.toString().c_str());
+			return true;
+		}
+
+		const uint64_t now = RR->node->now();
+
+		unsigned int breadth = 0;
+		Address nextHop[256]; // breadth is a uin8_t, so this is the max
+		InetAddress nextHopBestPathAddress[256];
+		unsigned int remainingHopsPtr = ZT_PACKET_IDX_PAYLOAD + 33 + vlf;
+		if ((ZT_PACKET_IDX_PAYLOAD + 31 + vlf) < size()) {
+			// unsigned int nextHopFlags = (*this)[ZT_PACKET_IDX_PAYLOAD + 31 + vlf]
+			breadth = (*this)[ZT_PACKET_IDX_PAYLOAD + 32 + vlf];
+			for(unsigned int h=0;h<breadth;++h) {
+				nextHop[h].setTo(field(remainingHopsPtr,ZT_ADDRESS_LENGTH),ZT_ADDRESS_LENGTH);
+				remainingHopsPtr += ZT_ADDRESS_LENGTH;
+				SharedPtr<Peer> nhp(RR->topology->getPeer(nextHop[h]));
+				if (nhp) {
+					Path *const rp = nhp->getBestPath(now);
+					if (rp)
+						nextHopBestPathAddress[h] = rp->address();
+				}
+			}
+		}
+
+		// Report back to originator, depending on flags and whether we are last hop
+		if ( ((flags & 0x01) != 0) || ((breadth == 0)&&((flags & 0x02) != 0)) ) {
+			Packet outp(originatorAddress,RR->identity.address(),Packet::VERB_CIRCUIT_TEST_REPORT);
+			outp.append((uint64_t)timestamp);
+			outp.append((uint64_t)testId);
+			outp.append((uint64_t)0); // field reserved for future use
+			outp.append((uint8_t)ZT_VENDOR_ZEROTIER);
+			outp.append((uint8_t)ZT_PROTO_VERSION);
+			outp.append((uint8_t)ZEROTIER_ONE_VERSION_MAJOR);
+			outp.append((uint8_t)ZEROTIER_ONE_VERSION_MINOR);
+			outp.append((uint16_t)ZEROTIER_ONE_VERSION_REVISION);
+			outp.append((uint16_t)ZT_PLATFORM_UNSPECIFIED);
+			outp.append((uint16_t)ZT_ARCHITECTURE_UNSPECIFIED);
+			outp.append((uint16_t)0); // error code, currently unused
+			outp.append((uint64_t)0); // flags, currently unused
+			outp.append((uint64_t)packetId());
+			peer->address().appendTo(outp);
+			outp.append((uint8_t)hops());
+			_localAddress.serialize(outp);
+			_remoteAddress.serialize(outp);
+			outp.append((uint16_t)0); // no additional fields
+			outp.append((uint8_t)breadth);
+			for(unsigned int h=0;h<breadth;++h) {
+				nextHop[h].appendTo(outp);
+				nextHopBestPathAddress[h].serialize(outp); // appends 0 if null InetAddress
+			}
+			RR->sw->send(outp,true,0);
+		}
+
+		// If there are next hops, forward the test along through the graph
+		if (breadth > 0) {
+			Packet outp(Address(),RR->identity.address(),Packet::VERB_CIRCUIT_TEST);
+			outp.append(field(ZT_PACKET_IDX_PAYLOAD,lengthOfSignedPortionAndSignature),lengthOfSignedPortionAndSignature);
+			const unsigned int previousHopCredentialPos = outp.size();
+			outp.append((uint16_t)0); // no previous hop credentials: default
+			if ((originatorCredentialNetworkConfig)&&(!originatorCredentialNetworkConfig.isPublic())&&(originatorCredentialNetworkConfig.com)) {
+				outp.append((uint8_t)0x01); // COM
+				originatorCredentialNetworkConfig.com.serialize(outp);
+				outp.setAt<uint16_t>(previousHopCredentialPos,(uint16_t)(outp.size() - (previousHopCredentialPos + 2)));
+			}
+			if (remainingHopsPtr < size())
+				outp.append(field(remainingHopsPtr,size() - remainingHopsPtr),size() - remainingHopsPtr);
+
+			for(unsigned int h=0;h<breadth;++h) {
+				if (RR->identity.address() != nextHop[h]) { // next hops that loop back to the current hop are not valid
+					outp.newInitializationVector();
+					outp.setDestination(nextHop[h]);
+					RR->sw->send(outp,true,originatorCredentialNetworkId);
+				}
+			}
+		}
+
+		peer->received(_localAddress,_remoteAddress,hops(),packetId(),Packet::VERB_CIRCUIT_TEST,0,Packet::VERB_NOP);
+	} catch ( ... ) {
+		TRACE("dropped CIRCUIT_TEST from %s(%s): unexpected exception",source().toString().c_str(),_remoteAddress.toString().c_str());
+	}
+	return true;
+}
+
+bool IncomingPacket::_doCIRCUIT_TEST_REPORT(const RuntimeEnvironment *RR,const SharedPtr<Peer> &peer)
+{
+	try {
+		ZT_CircuitTestReport report;
+		memset(&report,0,sizeof(report));
+
+		report.current = peer->address().toInt();
+		report.upstream = Address(field(ZT_PACKET_IDX_PAYLOAD + 52,ZT_ADDRESS_LENGTH),ZT_ADDRESS_LENGTH).toInt();
+		report.testId = at<uint64_t>(ZT_PACKET_IDX_PAYLOAD + 8);
+		report.timestamp = at<uint64_t>(ZT_PACKET_IDX_PAYLOAD);
+		report.remoteTimestamp = at<uint64_t>(ZT_PACKET_IDX_PAYLOAD + 16);
+		report.sourcePacketId = at<uint64_t>(ZT_PACKET_IDX_PAYLOAD + 44);
+		report.flags = at<uint64_t>(ZT_PACKET_IDX_PAYLOAD + 36);
+		report.sourcePacketHopCount = (*this)[ZT_PACKET_IDX_PAYLOAD + 57]; // end of fixed length headers: 58
+		report.errorCode = at<uint16_t>(ZT_PACKET_IDX_PAYLOAD + 34);
+		report.vendor = (enum ZT_Vendor)((*this)[ZT_PACKET_IDX_PAYLOAD + 24]);
+		report.protocolVersion = (*this)[ZT_PACKET_IDX_PAYLOAD + 25];
+		report.majorVersion = (*this)[ZT_PACKET_IDX_PAYLOAD + 26];
+		report.minorVersion = (*this)[ZT_PACKET_IDX_PAYLOAD + 27];
+		report.revision = at<uint16_t>(ZT_PACKET_IDX_PAYLOAD + 28);
+		report.platform = (enum ZT_Platform)at<uint16_t>(ZT_PACKET_IDX_PAYLOAD + 30);
+		report.architecture = (enum ZT_Architecture)at<uint16_t>(ZT_PACKET_IDX_PAYLOAD + 32);
+
+		const unsigned int receivedOnLocalAddressLen = reinterpret_cast<InetAddress *>(&(report.receivedOnLocalAddress))->deserialize(*this,ZT_PACKET_IDX_PAYLOAD + 58);
+		const unsigned int receivedFromRemoteAddressLen = reinterpret_cast<InetAddress *>(&(report.receivedFromRemoteAddress))->deserialize(*this,ZT_PACKET_IDX_PAYLOAD + 58 + receivedOnLocalAddressLen);
+
+		unsigned int nhptr = ZT_PACKET_IDX_PAYLOAD + 58 + receivedOnLocalAddressLen + receivedFromRemoteAddressLen;
+		nhptr += at<uint16_t>(nhptr) + 2; // add "additional field" length, which right now will be zero
+
+		report.nextHopCount = (*this)[nhptr++];
+		if (report.nextHopCount > ZT_CIRCUIT_TEST_MAX_HOP_BREADTH) // sanity check, shouldn't be possible
+			report.nextHopCount = ZT_CIRCUIT_TEST_MAX_HOP_BREADTH;
+		for(unsigned int h=0;h<report.nextHopCount;++h) {
+			report.nextHops[h].address = Address(field(nhptr,ZT_ADDRESS_LENGTH),ZT_ADDRESS_LENGTH).toInt(); nhptr += ZT_ADDRESS_LENGTH;
+			nhptr += reinterpret_cast<InetAddress *>(&(report.nextHops[h].physicalAddress))->deserialize(*this,nhptr);
+		}
+
+		RR->node->postCircuitTestReport(&report);
+	} catch ( ... ) {
+		TRACE("dropped CIRCUIT_TEST_REPORT from %s(%s): unexpected exception",source().toString().c_str(),_remoteAddress.toString().c_str());
+	}
+	return true;
+}
+
+bool IncomingPacket::_doREQUEST_PROOF_OF_WORK(const RuntimeEnvironment *RR,const SharedPtr<Peer> &peer)
+{
+	try {
+		// Right now this is only allowed from root servers -- may be allowed from controllers and relays later.
+		if (RR->topology->isRoot(peer->identity())) {
+			const uint64_t pid = packetId();
+			const unsigned int difficulty = (*this)[ZT_PACKET_IDX_PAYLOAD + 1];
+			const unsigned int challengeLength = at<uint16_t>(ZT_PACKET_IDX_PAYLOAD + 2);
+			if (challengeLength > ZT_PROTO_MAX_PACKET_LENGTH)
+				return true; // sanity check, drop invalid size
+			const unsigned char *challenge = field(ZT_PACKET_IDX_PAYLOAD + 4,challengeLength);
+
+			switch((*this)[ZT_PACKET_IDX_PAYLOAD]) {
+
+				// Salsa20/12+SHA512 hashcash
+				case 0x01: {
+					if (difficulty <= 14) {
+						unsigned char result[16];
+						computeSalsa2012Sha512ProofOfWork(difficulty,challenge,challengeLength,result);
+						TRACE("PROOF_OF_WORK computed for %s: difficulty==%u, challengeLength==%u, result: %.16llx%.16llx",peer->address().toString().c_str(),difficulty,challengeLength,Utils::ntoh(*(reinterpret_cast<const uint64_t *>(result))),Utils::ntoh(*(reinterpret_cast<const uint64_t *>(result + 8))));
+						Packet outp(peer->address(),RR->identity.address(),Packet::VERB_OK);
+						outp.append((unsigned char)Packet::VERB_REQUEST_PROOF_OF_WORK);
+						outp.append(pid);
+						outp.append((uint16_t)sizeof(result));
+						outp.append(result,sizeof(result));
+						outp.armor(peer->key(),true);
+						RR->node->putPacket(_localAddress,_remoteAddress,outp.data(),outp.size());
+					} else {
+						Packet outp(peer->address(),RR->identity.address(),Packet::VERB_ERROR);
+						outp.append((unsigned char)Packet::VERB_REQUEST_PROOF_OF_WORK);
+						outp.append(pid);
+						outp.append((unsigned char)Packet::ERROR_INVALID_REQUEST);
+						outp.armor(peer->key(),true);
+						RR->node->putPacket(_localAddress,_remoteAddress,outp.data(),outp.size());
+					}
+				}	break;
+
+				default:
+					TRACE("dropped REQUEST_PROOF_OF_WORK from %s(%s): unrecognized proof of work type",peer->address().toString().c_str(),_remoteAddress.toString().c_str());
+					break;
+			}
+
+			peer->received(_localAddress,_remoteAddress,hops(),pid,Packet::VERB_REQUEST_PROOF_OF_WORK,0,Packet::VERB_NOP);
+		} else {
+			TRACE("dropped REQUEST_PROOF_OF_WORK from %s(%s): not trusted enough",peer->address().toString().c_str(),_remoteAddress.toString().c_str());
+		}
+	} catch ( ... ) {
+		TRACE("dropped REQUEST_PROOF_OF_WORK from %s(%s): unexpected exception",peer->address().toString().c_str(),_remoteAddress.toString().c_str());
+	}
+	return true;
+}
+
+void IncomingPacket::computeSalsa2012Sha512ProofOfWork(unsigned int difficulty,const void *challenge,unsigned int challengeLength,unsigned char result[16])
+{
+	unsigned char salsabuf[131072]; // 131072 == protocol constant, size of memory buffer for this proof of work function
+	char candidatebuf[ZT_PROTO_MAX_PACKET_LENGTH + 256];
+	unsigned char shabuf[ZT_SHA512_DIGEST_LEN];
+	const uint64_t s20iv = 0; // zero IV for Salsa20
+	char *const candidate = (char *)(( ((uintptr_t)&(candidatebuf[0])) | 0xf ) + 1); // align to 16-byte boundary to ensure that uint64_t type punning of initial nonce is okay
+	Salsa20 s20;
+	unsigned int d;
+	unsigned char *p;
+
+	Utils::getSecureRandom(candidate,16);
+	memcpy(candidate + 16,challenge,challengeLength);
+
+	if (difficulty > 512)
+		difficulty = 512; // sanity check
+
+try_salsa2012sha512_again:
+	++*(reinterpret_cast<volatile uint64_t *>(candidate));
+
+	SHA512::hash(shabuf,candidate,16 + challengeLength);
+	s20.init(shabuf,256,&s20iv);
+	memset(salsabuf,0,sizeof(salsabuf));
+	s20.encrypt12(salsabuf,salsabuf,sizeof(salsabuf));
+	SHA512::hash(shabuf,salsabuf,sizeof(salsabuf));
+
+	d = difficulty;
+	p = shabuf;
+	while (d >= 8) {
+		if (*(p++))
+			goto try_salsa2012sha512_again;
+		d -= 8;
+	}
+	if (d > 0) {
+		if ( ((((unsigned int)*p) << d) & 0xff00) != 0 )
+			goto try_salsa2012sha512_again;
+	}
+
+	memcpy(result,candidate,16);
+}
+
+bool IncomingPacket::testSalsa2012Sha512ProofOfWorkResult(unsigned int difficulty,const void *challenge,unsigned int challengeLength,const unsigned char proposedResult[16])
+{
+	unsigned char salsabuf[131072]; // 131072 == protocol constant, size of memory buffer for this proof of work function
+	char candidate[ZT_PROTO_MAX_PACKET_LENGTH + 256];
+	unsigned char shabuf[ZT_SHA512_DIGEST_LEN];
+	const uint64_t s20iv = 0; // zero IV for Salsa20
+	Salsa20 s20;
+	unsigned int d;
+	unsigned char *p;
+
+	if (difficulty > 512)
+		difficulty = 512; // sanity check
+
+	memcpy(candidate,proposedResult,16);
+	memcpy(candidate + 16,challenge,challengeLength);
+
+	SHA512::hash(shabuf,candidate,16 + challengeLength);
+	s20.init(shabuf,256,&s20iv);
+	memset(salsabuf,0,sizeof(salsabuf));
+	s20.encrypt12(salsabuf,salsabuf,sizeof(salsabuf));
+	SHA512::hash(shabuf,salsabuf,sizeof(salsabuf));
+
+	d = difficulty;
+	p = shabuf;
+	while (d >= 8) {
+		if (*(p++))
+			return false;
+		d -= 8;
+	}
+	if (d > 0) {
+		if ( ((((unsigned int)*p) << d) & 0xff00) != 0 )
+			return false;
+	}
+
+	return true;
+}
+
+void IncomingPacket::_sendErrorNeedCertificate(const RuntimeEnvironment *RR,const SharedPtr<Peer> &peer,uint64_t nwid)
+{
+	Packet outp(source(),RR->identity.address(),Packet::VERB_ERROR);
+	outp.append((unsigned char)verb());
+	outp.append(packetId());
+	outp.append((unsigned char)Packet::ERROR_NEED_MEMBERSHIP_CERTIFICATE);
+	outp.append(nwid);
+	outp.armor(peer->key(),true);
+	RR->node->putPacket(_localAddress,_remoteAddress,outp.data(),outp.size());
+}
+
+} // namespace ZeroTier