More major Switch refactor work... still in progress.

1 files changed, 368 insertions, 0 deletions

diff --git a/node/PacketDecoder.cpp b/node/PacketDecoder.cpp
index 558ab63b..79dca1d0 100644
--- a/node/PacketDecoder.cpp
+++ b/node/PacketDecoder.cpp
@@ -29,12 +29,380 @@
 #include "Topology.hpp"
 #include "PacketDecoder.hpp"
 #include "Switch.hpp"
+#include "Peer.hpp"
 
 namespace ZeroTier {
 
 bool PacketDecoder::tryDecode(const RuntimeEnvironment *_r)
 	throw(std::out_of_range,std::runtime_error)
 {
+	Address source(source());
+
+	if ((!encrypted())&&(verb() == Packet::VERB_HELLO)) {
+		// Unencrypted HELLOs are handled here since they are used to
+		// populate our identity cache in the first place. Thus we might get
+		// a HELLO for someone for whom we don't have a Peer record.
+		TRACE("HELLO from %s(%s)",source.toString().c_str(),fromAddr.toString().c_str());
+		_doHELLO(localPort,fromAddr,packet);
+		return true;
+	}
+
+	SharedPtr<Peer> peer = _r->topology->getPeer(source);
+	if (peer) {
+		uint64_t now = Utils::now();
+		unsigned int latency = 0;
+
+		if (!packet.hmacVerify(peer->macKey())) {
+			TRACE("dropped packet from %s(%s), HMAC authentication failed (size: %u)",source.toString().c_str(),fromAddr.toString().c_str(),packet.size());
+			return true;
+		}
+
+		if (packet.encrypted()) {
+			packet.decrypt(peer->cryptKey());
+		} else {
+			// Unencrypted is tolerated in case we want to run this on
+			// devices where squeezing out cycles matters. HMAC is
+			// what's really important.
+			TRACE("ODD: %s from %s(%s) wasn't encrypted",Packet::verbString(packet.verb()),source.toString().c_str(),fromAddr.toString().c_str());
+		}
+
+		if (!packet.uncompress()) {
+			TRACE("dropped packet from %s(%s), compressed data invalid",source.toString().c_str(),fromAddr.toString().c_str());
+			return true;
+		}
+
+		switch(packet.verb()) {
+			case Packet::VERB_NOP:
+				TRACE("NOP from %s(%s)",source.toString().c_str(),fromAddr.toString().c_str());
+				break;
+			case Packet::VERB_HELLO:
+				// HELLO is normally handled up top, but this is legal. Pointless, but legal.
+				_doHELLO(localPort,fromAddr,packet);
+				break;
+			case Packet::VERB_ERROR:
+				try {
+#ifdef ZT_TRACE
+					Packet::Verb inReVerb = (Packet::Verb)packet[ZT_PROTO_VERB_ERROR_IDX_IN_RE_VERB];
+					Packet::ErrorCode errorCode = (Packet::ErrorCode)packet[ZT_PROTO_VERB_ERROR_IDX_ERROR_CODE];
+					TRACE("ERROR %s from %s(%s) in-re %s",Packet::errorString(errorCode),source.toString().c_str(),fromAddr.toString().c_str(),Packet::verbString(inReVerb));
+#endif
+					// TODO:
+					// The fact is that the protocol works fine without error handling.
+					// The only error that really needs to be handled here is duplicate
+					// identity collision, which if it comes from a supernode should cause
+					// us to restart and regenerate a new identity.
+				} catch (std::exception &ex) {
+					TRACE("dropped ERROR from %s(%s): unexpected exception: %s",source.toString().c_str(),fromAddr.toString().c_str(),ex.what());
+				} catch ( ... ) {
+					TRACE("dropped ERROR from %s(%s): unexpected exception: (unknown)",source.toString().c_str(),fromAddr.toString().c_str());
+				}
+				break;
+			case Packet::VERB_OK:
+				try {
+					Packet::Verb inReVerb = (Packet::Verb)packet[ZT_PROTO_VERB_OK_IDX_IN_RE_VERB];
+					switch(inReVerb) {
+						case Packet::VERB_HELLO:
+							// OK from HELLO permits computation of latency.
+							latency = std::min((unsigned int)(now - packet.at<uint64_t>(ZT_PROTO_VERB_HELLO__OK__IDX_TIMESTAMP)),(unsigned int)0xffff);
+							TRACE("%s(%s): OK(HELLO), latency: %u",source.toString().c_str(),fromAddr.toString().c_str(),latency);
+							break;
+						case Packet::VERB_WHOIS:
+							// Right now we only query supernodes for WHOIS and only accept
+							// OK back from them. If we query other nodes, we'll have to
+							// do something to prevent WHOIS cache poisoning such as
+							// using the packet ID field in the OK packet to match with the
+							// original query. Technically we should be doing this anyway.
+							TRACE("%s(%s): OK(%s)",source.toString().c_str(),fromAddr.toString().c_str(),Packet::verbString(inReVerb));
+							if (_r->topology->isSupernode(source))
+								_r->topology->addPeer(SharedPtr<Peer>(new Peer(_r->identity,Identity(packet,ZT_PROTO_VERB_WHOIS__OK__IDX_IDENTITY))),&Switch::_CBaddPeerFromWhois,this);
+							break;
+						default:
+							TRACE("%s(%s): OK(%s)",source.toString().c_str(),fromAddr.toString().c_str(),Packet::verbString(inReVerb));
+							break;
+					}
+				} catch (std::exception &ex) {
+					TRACE("dropped OK from %s(%s): unexpected exception: %s",source.toString().c_str(),fromAddr.toString().c_str(),ex.what());
+				} catch ( ... ) {
+					TRACE("dropped OK from %s(%s): unexpected exception: (unknown)",source.toString().c_str(),fromAddr.toString().c_str());
+				}
+				break;
+			case Packet::VERB_WHOIS:
+				if (packet.payloadLength() == ZT_ADDRESS_LENGTH) {
+					SharedPtr<Peer> p(_r->topology->getPeer(Address(packet.payload())));
+					if (p) {
+						Packet outp(source,_r->identity.address(),Packet::VERB_OK);
+						outp.append((unsigned char)Packet::VERB_WHOIS);
+						outp.append(packet.packetId());
+						p->identity().serialize(outp,false);
+						outp.encrypt(peer->cryptKey());
+						outp.hmacSet(peer->macKey());
+						_r->demarc->send(localPort,fromAddr,outp.data(),outp.size(),-1);
+						TRACE("sent WHOIS response to %s for %s",source.toString().c_str(),Address(packet.payload()).toString().c_str());
+					} else {
+						Packet outp(source,_r->identity.address(),Packet::VERB_ERROR);
+						outp.append((unsigned char)Packet::VERB_WHOIS);
+						outp.append(packet.packetId());
+						outp.append((unsigned char)Packet::ERROR_NOT_FOUND);
+						outp.append(packet.payload(),ZT_ADDRESS_LENGTH);
+						outp.encrypt(peer->cryptKey());
+						outp.hmacSet(peer->macKey());
+						_r->demarc->send(localPort,fromAddr,outp.data(),outp.size(),-1);
+						TRACE("sent WHOIS ERROR to %s for %s (not found)",source.toString().c_str(),Address(packet.payload()).toString().c_str());
+					}
+				} else {
+					TRACE("dropped WHOIS from %s(%s): missing or invalid address",source.toString().c_str(),fromAddr.toString().c_str());
+				}
+				break;
+			case Packet::VERB_RENDEZVOUS:
+				try {
+					Address with(packet.field(ZT_PROTO_VERB_RENDEZVOUS_IDX_ZTADDRESS,ZT_ADDRESS_LENGTH));
+					RendezvousQueueEntry qe;
+					if (_r->topology->getPeer(with)) {
+						unsigned int port = packet.at<uint16_t>(ZT_PROTO_VERB_RENDEZVOUS_IDX_PORT);
+						unsigned int addrlen = packet[ZT_PROTO_VERB_RENDEZVOUS_IDX_ADDRLEN];
+						if ((port > 0)&&((addrlen == 4)||(addrlen == 16))) {
+							qe.inaddr.set(packet.field(ZT_PROTO_VERB_RENDEZVOUS_IDX_ADDRESS,addrlen),addrlen,port);
+							qe.fireAtTime = now + ZT_RENDEZVOUS_NAT_T_DELAY; // then send real packet in a few ms
+							qe.localPort = _r->demarc->pick(qe.inaddr);
+							TRACE("RENDEZVOUS from %s says %s might be at %s, starting NAT-t",source.toString().c_str(),with.toString().c_str(),qe.inaddr.toString().c_str());
+							_r->demarc->send(qe.localPort,qe.inaddr,"\0",1,ZT_FIREWALL_OPENER_HOPS); // start with firewall opener
+							{
+								Mutex::Lock _l(_rendezvousQueue_m);
+								_rendezvousQueue[with] = qe;
+							}
+						} else {
+							TRACE("dropped corrupt RENDEZVOUS from %s(%s) (bad address or port)",source.toString().c_str(),fromAddr.toString().c_str());
+						}
+					} else {
+						TRACE("ignored RENDEZVOUS from %s(%s) to meet unknown peer %s",source.toString().c_str(),fromAddr.toString().c_str(),with.toString().c_str());
+					}
+				} catch (std::exception &ex) {
+					TRACE("dropped RENDEZVOUS from %s(%s): %s",source.toString().c_str(),fromAddr.toString().c_str(),ex.what());
+				} catch ( ... ) {
+					TRACE("dropped RENDEZVOUS from %s(%s): unexpected exception",source.toString().c_str(),fromAddr.toString().c_str());
+				}
+				break;
+			case Packet::VERB_FRAME:
+				try {
+					SharedPtr<Network> network(_r->nc->network(packet.at<uint64_t>(ZT_PROTO_VERB_FRAME_IDX_NETWORK_ID)));
+					if (network) {
+						if (network->isAllowed(source)) {
+							unsigned int etherType = packet.at<uint16_t>(ZT_PROTO_VERB_FRAME_IDX_ETHERTYPE);
+							if ((etherType != ZT_ETHERTYPE_ARP)&&(etherType != ZT_ETHERTYPE_IPV4)&&(etherType != ZT_ETHERTYPE_IPV6)) {
+								TRACE("dropped FRAME from %s: unsupported ethertype",source.toString().c_str());
+							} else if (packet.size() > ZT_PROTO_VERB_FRAME_IDX_PAYLOAD) {
+								network->tap().put(source.toMAC(),network->tap().mac(),etherType,packet.data() + ZT_PROTO_VERB_FRAME_IDX_PAYLOAD,packet.size() - ZT_PROTO_VERB_FRAME_IDX_PAYLOAD);
+							}
+						} else {
+							TRACE("dropped FRAME from %s(%s): not a member of closed network %llu",source.toString().c_str(),fromAddr.toString().c_str(),network->id());
+						}
+					} else {
+						TRACE("dropped FRAME from %s(%s): network %llu unknown",source.toString().c_str(),fromAddr.toString().c_str(),packet.at<uint64_t>(ZT_PROTO_VERB_FRAME_IDX_NETWORK_ID));
+					}
+				} catch (std::exception &ex) {
+					TRACE("dropped FRAME from %s(%s): unexpected exception: %s",source.toString().c_str(),fromAddr.toString().c_str(),ex.what());
+				} catch ( ... ) {
+					TRACE("dropped FRAME from %s(%s): unexpected exception: (unknown)",source.toString().c_str(),fromAddr.toString().c_str());
+				}
+				break;
+			case Packet::VERB_MULTICAST_LIKE:
+				try {
+					unsigned int ptr = ZT_PACKET_IDX_PAYLOAD;
+					unsigned int numAccepted = 0;
+
+					// Iterate through 18-byte network,MAC,ADI tuples:
+					while ((ptr + 18) <= packet.size()) {
+						uint64_t nwid = packet.at<uint64_t>(ptr); ptr += 8;
+						SharedPtr<Network> network(_r->nc->network(nwid));
+						if (network) {
+							if (network->isAllowed(source)) {
+								MAC mac(packet.field(ptr,6)); ptr += 6;
+								uint32_t adi = packet.at<uint32_t>(ptr); ptr += 4;
+								TRACE("peer %s likes multicast group %s:%.8lx on network %llu",source.toString().c_str(),mac.toString().c_str(),(unsigned long)adi,nwid);
+								_multicaster.likesMulticastGroup(nwid,MulticastGroup(mac,adi),source,now);
+								++numAccepted;
+							} else {
+								TRACE("ignored MULTICAST_LIKE from %s(%s): not a member of closed network %llu",source.toString().c_str(),fromAddr.toString().c_str(),nwid);
+							}
+						} else {
+							TRACE("ignored MULTICAST_LIKE from %s(%s): network %llu unknown or we are not a member",source.toString().c_str(),fromAddr.toString().c_str(),nwid);
+						}
+					}
+
+					Packet outp(source,_r->identity.address(),Packet::VERB_OK);
+					outp.append((unsigned char)Packet::VERB_MULTICAST_LIKE);
+					outp.append(packet.packetId());
+					outp.append((uint16_t)numAccepted);
+					outp.encrypt(peer->cryptKey());
+					outp.hmacSet(peer->macKey());
+					_r->demarc->send(localPort,fromAddr,outp.data(),outp.size(),-1);
+				} catch (std::exception &ex) {
+					TRACE("dropped MULTICAST_LIKE from %s(%s): unexpected exception: %s",source.toString().c_str(),fromAddr.toString().c_str(),ex.what());
+				} catch ( ... ) {
+					TRACE("dropped MULTICAST_LIKE from %s(%s): unexpected exception: (unknown)",source.toString().c_str(),fromAddr.toString().c_str());
+				}
+				break;
+			case Packet::VERB_MULTICAST_FRAME:
+				try {
+					SharedPtr<Network> network(_r->nc->network(packet.at<uint64_t>(ZT_PROTO_VERB_MULTICAST_FRAME_IDX_NETWORK_ID)));
+					if (network) {
+						if (network->isAllowed(source)) {
+							if (packet.size() > ZT_PROTO_VERB_MULTICAST_FRAME_IDX_PAYLOAD) {
+								Address originalSubmitterAddress(packet.field(ZT_PROTO_VERB_MULTICAST_FRAME_IDX_SUBMITTER_ADDRESS,ZT_ADDRESS_LENGTH));
+								MAC fromMac(packet.field(ZT_PROTO_VERB_MULTICAST_FRAME_IDX_SOURCE_MAC,6));
+								MulticastGroup mg(MAC(packet.field(ZT_PROTO_VERB_MULTICAST_FRAME_IDX_DESTINATION_MAC,6)),packet.at<uint32_t>(ZT_PROTO_VERB_MULTICAST_FRAME_IDX_ADI));
+								unsigned int hops = packet[ZT_PROTO_VERB_MULTICAST_FRAME_IDX_HOP_COUNT];
+								unsigned int etherType = packet.at<uint16_t>(ZT_PROTO_VERB_MULTICAST_FRAME_IDX_ETHERTYPE);
+								unsigned int datalen = packet.at<uint16_t>(ZT_PROTO_VERB_MULTICAST_FRAME_IDX_PAYLOAD_LENGTH);
+								unsigned int signaturelen = packet.at<uint16_t>(ZT_PROTO_VERB_MULTICAST_FRAME_IDX_SIGNATURE_LENGTH);
+								unsigned char *dataAndSignature = packet.field(ZT_PROTO_VERB_MULTICAST_FRAME_IDX_PAYLOAD,datalen + signaturelen);
+
+								bool isDuplicate = _multicaster.checkAndUpdateMulticastHistory(fromMac,mg,payload,payloadLen,network->id(),now);
+
+								if (originalSubmitterAddress == _r->identity.address()) {
+									// Technically should not happen, since the original submitter is
+									// excluded from consideration as a propagation recipient.
+									TRACE("dropped boomerang MULTICAST_FRAME received from %s(%s)",source.toString().c_str(),fromAddr.toString().c_str());
+								} else if ((!isDuplicate)||(_r->topology.isSupernode(_r->identity.address()))) {
+									// If I am a supernode, I will repeatedly propagate duplicates. That's
+									// because supernodes are used to bridge sparse multicast groups. Non-
+									// supernodes will ignore duplicates completely.
+									SharedPtr<Peer> originalSubmitter(_r->topology->getPeer(originalSubmitterAddress));
+									if (!originalSubmitter) {
+										TRACE("requesting WHOIS on original multicast frame submitter %s",originalSubmitterAddress.toString().c_str());
+										_requestWhois(originalSubmitterAddress,packet.packetId());
+										return false;
+									} else if (Multicaster::verifyMulticastPacket(originalSubmitter->identity(),fromMac,mg,etherType,data,datalen,dataAndSignature + datalen,signaturelen)) {
+										if (!isDuplicate)
+											network->tap().put(fromMac,mg.mac(),etherType,payload,payloadLen);
+										_propagateMulticast(network,originalSubmitterAddress,source,packet.field(ZT_PROTO_VERB_MULTICAST_FRAME_IDX_BLOOM,ZT_PROTO_VERB_MULTICAST_FRAME_BLOOM_FILTER_SIZE),mg,hops+1,fromMac,etherType,payload,payloadLen);
+									} else {
+										LOG("rejected MULTICAST_FRAME from %s(%s) due to failed signature check (claims original sender %s)",source.toString().c_str(),fromAddr.toString().c_str(),originalSubmitterAddress.toString().c_str());
+									}
+								} else {
+									TRACE("dropped redundant MULTICAST_FRAME from %s(%s)",source.toString().c_str(),fromAddr.toString().c_str());
+								}
+							} else {
+								TRACE("dropped MULTICAST_FRAME from %s(%s): invalid short packet",source.toString().c_str(),fromAddr.toString().c_str());
+							}
+						} else {
+							TRACE("dropped MULTICAST_FRAME from %s(%s): not a member of closed network %llu",source.toString().c_str(),fromAddr.toString().c_str(),network->id());
+						}
+					} else {
+						TRACE("dropped MULTICAST_FRAME from %s(%s): network %llu unknown or we are not a member",source.toString().c_str(),fromAddr.toString().c_str(),packet.at<uint64_t>(ZT_PROTO_VERB_MULTICAST_FRAME_IDX_NETWORK_ID));
+					}
+				} catch (std::exception &ex) {
+					TRACE("dropped MULTICAST_FRAME from %s(%s): unexpected exception: %s",source.toString().c_str(),fromAddr.toString().c_str(),ex.what());
+				} catch ( ... ) {
+					TRACE("dropped MULTICAST_FRAME from %s(%s): unexpected exception: (unknown)",source.toString().c_str(),fromAddr.toString().c_str());
+				}
+				break;
+			default:
+				// This might be something from a new or old version of the protocol.
+				// Technically it passed HMAC so the packet is still valid, but we
+				// ignore it.
+				TRACE("ignored unrecognized verb %.2x from %s(%s)",(unsigned int)packet.verb(),source.toString().c_str(),fromAddr.toString().c_str());
+				break;
+		}
+
+		// Update peer timestamps and learn new links. This must only ever
+		// be called on an authenticated and technically valid packet, since
+		// we only learn paths to peers over the WAN by hearing directly
+		// from them over those paths. (Or by having them authoritatively
+		// and statically defined, like with supernodes, but that's done
+		// elsewhere.)
+		peer->onReceive(_r,localPort,fromAddr,latency,packet.hops(),packet.verb(),now);
+	} else {
+		_requestWhois(source,packet.packetId());
+		return false;
+	}
+
+	return true;
+}
+
+void PacketDecoder::_doHELLO(Demarc::Port localPort,const InetAddress &fromAddr)
+{
+	Address source(source());
+
+	try {
+		unsigned int protoVersion = packet[ZT_PROTO_VERB_HELLO_IDX_PROTOCOL_VERSION];
+		unsigned int vMajor = packet[ZT_PROTO_VERB_HELLO_IDX_MAJOR_VERSION];
+		unsigned int vMinor = packet[ZT_PROTO_VERB_HELLO_IDX_MINOR_VERSION];
+		unsigned int vRevision = packet.at<uint16_t>(ZT_PROTO_VERB_HELLO_IDX_REVISION);
+		uint64_t timestamp = packet.at<uint64_t>(ZT_PROTO_VERB_HELLO_IDX_TIMESTAMP);
+		Identity id(packet,ZT_PROTO_VERB_HELLO_IDX_IDENTITY);
+
+		SharedPtr<Peer> candidate(new Peer(_r->identity,id));
+		candidate->setPathAddress(fromAddr,false);
+
+		// Initial sniff test
+		if (protoVersion != ZT_PROTO_VERSION) {
+			TRACE("rejected HELLO from %s(%s): invalid protocol version",source.toString().c_str(),fromAddr.toString().c_str());
+			Packet outp(source,_r->identity.address(),Packet::VERB_ERROR);
+			outp.append((unsigned char)Packet::VERB_HELLO);
+			outp.append(packet.packetId());
+			outp.append((unsigned char)Packet::ERROR_BAD_PROTOCOL_VERSION);
+			outp.encrypt(candidate->cryptKey());
+			outp.hmacSet(candidate->macKey());
+			_r->demarc->send(localPort,fromAddr,outp.data(),outp.size(),-1);
+			return;
+		}
+		if (id.address().isReserved()) {
+			TRACE("rejected HELLO from %s(%s): identity has reserved address",source.toString().c_str(),fromAddr.toString().c_str());
+			Packet outp(source,_r->identity.address(),Packet::VERB_ERROR);
+			outp.append((unsigned char)Packet::VERB_HELLO);
+			outp.append(packet.packetId());
+			outp.append((unsigned char)Packet::ERROR_IDENTITY_INVALID);
+			outp.encrypt(candidate->cryptKey());
+			outp.hmacSet(candidate->macKey());
+			_r->demarc->send(localPort,fromAddr,outp.data(),outp.size(),-1);
+			return;
+		}
+		if (id.address() != source) {
+			TRACE("rejected HELLO from %s(%s): identity is not for sender of packet (HELLO is a self-announcement)",source.toString().c_str(),fromAddr.toString().c_str());
+			Packet outp(source,_r->identity.address(),Packet::VERB_ERROR);
+			outp.append((unsigned char)Packet::VERB_HELLO);
+			outp.append(packet.packetId());
+			outp.append((unsigned char)Packet::ERROR_INVALID_REQUEST);
+			outp.encrypt(candidate->cryptKey());
+			outp.hmacSet(candidate->macKey());
+			_r->demarc->send(localPort,fromAddr,outp.data(),outp.size(),-1);
+			return;
+		}
+
+		// Is this a HELLO for a peer we already know? If so just update its
+		// packet receive stats and send an OK.
+		SharedPtr<Peer> existingPeer(_r->topology->getPeer(id.address()));
+		if ((existingPeer)&&(existingPeer->identity() == id)) {
+			existingPeer->onReceive(_r,localPort,fromAddr,0,packet.hops(),Packet::VERB_HELLO,Utils::now());
+
+			Packet outp(source,_r->identity.address(),Packet::VERB_OK);
+			outp.append((unsigned char)Packet::VERB_HELLO);
+			outp.append(packet.packetId());
+			outp.append(timestamp);
+			outp.encrypt(existingPeer->cryptKey());
+			outp.hmacSet(existingPeer->macKey());
+			_r->demarc->send(localPort,fromAddr,outp.data(),outp.size(),-1);
+			return;
+		}
+
+		// Otherwise we call addPeer() and set up a callback to handle the verdict
+		_CBaddPeerFromHello_Data *arg = new _CBaddPeerFromHello_Data;
+		arg->parent = this;
+		arg->source = source;
+		arg->fromAddr = fromAddr;
+		arg->localPort = localPort;
+		arg->vMajor = vMajor;
+		arg->vMinor = vMinor;
+		arg->vRevision = vRevision;
+		arg->helloPacketId = packet.packetId();
+		arg->helloTimestamp = timestamp;
+		_r->topology->addPeer(candidate,&Switch::_CBaddPeerFromHello,arg);
+	} catch (std::exception &ex) {
+		TRACE("dropped HELLO from %s(%s): %s",source.toString().c_str(),fromAddr.toString().c_str(),ex.what());
+	} catch ( ... ) {
+		TRACE("dropped HELLO from %s(%s): unexpected exception",source.toString().c_str(),fromAddr.toString().c_str());
+	}
 }
 
 } // namespace ZeroTier