i2pd/I2NPProtocol.cpp

#include <string.h>
#include <atomic>
#include "I2PEndian.h"
#include <cryptopp/gzip.h>
#include "ElGamal.h"
#include "Timestamp.h"
#include "RouterContext.h"
#include "NetDb.h"
#include "Tunnel.h"
#include "base64.h"
#include "Transports.h"
#include "Garlic.h"
#include "I2NPProtocol.h"

using namespace i2p::transport;

namespace i2p
{
	I2NPMessage * NewI2NPMessage ()
	{
		return new I2NPMessageBuffer<I2NP_MAX_MESSAGE_SIZE>();
	}
	
	I2NPMessage * NewI2NPShortMessage ()
	{
		return new I2NPMessageBuffer<I2NP_MAX_SHORT_MESSAGE_SIZE>();
	}

	I2NPMessage * NewI2NPMessage (size_t len)
	{
		return (len < I2NP_MAX_SHORT_MESSAGE_SIZE/2) ? NewI2NPShortMessage () : NewI2NPMessage ();
	}	
	
	void DeleteI2NPMessage (I2NPMessage * msg)
	{
		delete msg;
	}	

	static std::atomic<uint32_t> I2NPmsgID(0); // TODO: create class
	void FillI2NPMessageHeader (I2NPMessage * msg, I2NPMessageType msgType, uint32_t replyMsgID)
	{
		msg->SetTypeID (msgType);
		if (replyMsgID) // for tunnel creation
			msg->SetMsgID (replyMsgID); 
		else
		{	
			msg->SetMsgID (I2NPmsgID);
			I2NPmsgID++;
		}	
		msg->SetExpiration (i2p::util::GetMillisecondsSinceEpoch () + 5000); // TODO: 5 secs is a magic number
		msg->UpdateSize ();
		msg->UpdateChks ();
	}		
	
	void RenewI2NPMessageHeader (I2NPMessage * msg)
	{
		if (msg)
		{
			msg->SetMsgID (I2NPmsgID);
			I2NPmsgID++;
			msg->SetExpiration (i2p::util::GetMillisecondsSinceEpoch () + 5000); 		
		}
	}

	I2NPMessage * CreateI2NPMessage (I2NPMessageType msgType, const uint8_t * buf, int len, uint32_t replyMsgID)
	{
		I2NPMessage * msg = NewI2NPMessage (len);
		memcpy (msg->GetPayload (), buf, len);
		msg->len += len;
		FillI2NPMessageHeader (msg, msgType, replyMsgID);
		return msg;
	}	

	I2NPMessage * CreateI2NPMessage (const uint8_t * buf, int len, i2p::tunnel::InboundTunnel * from)
	{
		I2NPMessage * msg = NewI2NPMessage ();
		memcpy (msg->GetBuffer (), buf, len);
		msg->len = msg->offset + len;
		msg->from = from;
		return msg;
	}	
	
	I2NPMessage * CreateDeliveryStatusMsg (uint32_t msgID)
	{
		I2NPMessage * m = NewI2NPMessage ();
		uint8_t * buf = m->GetPayload ();
		if (msgID)
		{
			htobe32buf (buf + DELIVERY_STATUS_MSGID_OFFSET, msgID);
			htobe64buf (buf + DELIVERY_STATUS_TIMESTAMP_OFFSET, i2p::util::GetMillisecondsSinceEpoch ());
		}
		else // for SSU establishment
		{
			htobe32buf (buf + DELIVERY_STATUS_MSGID_OFFSET, i2p::context.GetRandomNumberGenerator ().GenerateWord32 ());
			htobe64buf (buf + DELIVERY_STATUS_TIMESTAMP_OFFSET, 2); // netID = 2
		}	
		m->len += DELIVERY_STATUS_SIZE;
		FillI2NPMessageHeader (m, eI2NPDeliveryStatus);
		return m;
	}

	I2NPMessage * CreateDatabaseLookupMsg (const uint8_t * key, const uint8_t * from, 
		uint32_t replyTunnelID, bool exploratory, std::set<i2p::data::IdentHash> * excludedPeers,
	    bool encryption, i2p::tunnel::TunnelPool * pool)
	{
		I2NPMessage * m = NewI2NPMessage ();
		uint8_t * buf = m->GetPayload ();
		memcpy (buf, key, 32); // key
		buf += 32;
		memcpy (buf, from, 32); // from
		buf += 32;
		if (replyTunnelID)
		{
			*buf = encryption ? 0x03: 0x01; // set delivery flag
			htobe32buf (buf+1, replyTunnelID);
			buf += 5;
		}
		else
		{	
			encryption = false; // encryption can we set for tunnels only
			*buf = 0; // flag
			buf++;
		}	
		
		if (exploratory)
		{
			htobe16buf (buf,1); // one exlude record
			buf += 2;
			// reply with non-floodfill routers only
			memset (buf, 0, 32);
			buf += 32;
		}
		else
		{
			if (excludedPeers)
			{
				int cnt = excludedPeers->size ();
				htobe16buf (buf, cnt);
				buf += 2;
				for (auto& it: *excludedPeers)
				{
					memcpy (buf, it, 32);
					buf += 32;
				}	
			}
			else
			{	
				// nothing to exclude
				htobuf16 (buf, 0);
				buf += 2;
			}	
		}	
		if (encryption)
		{
			// session key and tag for reply
			auto& rnd = i2p::context.GetRandomNumberGenerator ();
			rnd.GenerateBlock (buf, 32); // key
			buf[32] = 1; // 1 tag
			rnd.GenerateBlock (buf + 33, 32); // tag
			if (pool && pool->GetLocalDestination ())
				pool->GetLocalDestination ()->SubmitSessionKey (buf, buf + 33); // introduce new key-tag to garlic engine
			else
				LogPrint ("Destination for encrypteed reply not specified");
			buf += 65;
		}	
		m->len += (buf - m->GetPayload ()); 
		FillI2NPMessageHeader (m, eI2NPDatabaseLookup);
		return m; 
	}	

	I2NPMessage * CreateLeaseSetDatabaseLookupMsg (const i2p::data::IdentHash& dest, 
		const std::set<i2p::data::IdentHash>& excludedFloodfills,
		const i2p::tunnel::InboundTunnel * replyTunnel, const uint8_t * replyKey, const uint8_t * replyTag)
	{
		I2NPMessage * m = NewI2NPMessage ();
		uint8_t * buf = m->GetPayload ();
		memcpy (buf, dest, 32); // key
		buf += 32;
		memcpy (buf, replyTunnel->GetNextIdentHash (), 32); // reply tunnel GW
		buf += 32;
		*buf = 7; // flags (01 - tunnel, 10 - encrypted, 0100 - LS lookup
		htobe32buf (buf + 1, replyTunnel->GetNextTunnelID ()); // reply tunnel ID
		buf += 5;
		
		// excluded
		int cnt = excludedFloodfills.size ();
		htobe16buf (buf, cnt);
		buf += 2;
		if (cnt > 0)
		{
			for (auto& it: excludedFloodfills)
			{
				memcpy (buf, it, 32);
				buf += 32;
			}
		}	
		// encryption
		memcpy (buf, replyKey, 32);
		buf[32] = 1; // 1 tag
		memcpy (buf + 33, replyTag, 32);
		buf += 65;

		m->len += (buf - m->GetPayload ()); 
		FillI2NPMessageHeader (m, eI2NPDatabaseLookup);
		return m; 		  			
	}		
			
	

	I2NPMessage * CreateDatabaseSearchReply (const i2p::data::IdentHash& ident, 
		const i2p::data::RouterInfo * floodfill)
	{
		I2NPMessage * m = NewI2NPShortMessage ();
		uint8_t * buf = m->GetPayload ();
		size_t len = 0;
		memcpy (buf, ident, 32);
		len += 32;
		buf[len] = floodfill ? 1 : 0; // 1 router for now
		len++;
		if (floodfill)
		{
			memcpy (buf + len, floodfill->GetIdentHash (), 32);
			len += 32;
		}	
		memcpy (buf + len, i2p::context.GetRouterInfo ().GetIdentHash (), 32);
		len += 32;	
		m->len += len;
		FillI2NPMessageHeader (m, eI2NPDatabaseSearchReply);
		return m; 
	}	
	
	I2NPMessage * CreateDatabaseStoreMsg (const i2p::data::RouterInfo * router)
	{
		if (!router) // we send own RouterInfo
			router = &context.GetRouterInfo ();

		I2NPMessage * m = NewI2NPShortMessage ();
		uint8_t * payload = m->GetPayload ();		

		memcpy (payload + DATABASE_STORE_KEY_OFFSET, router->GetIdentHash (), 32);
		payload[DATABASE_STORE_TYPE_OFFSET] = 0;
		htobe32buf (payload + DATABASE_STORE_REPLY_TOKEN_OFFSET, 0);
		
		CryptoPP::Gzip compressor;
		compressor.Put (router->GetBuffer (), router->GetBufferLen ());
		compressor.MessageEnd();
		auto size = compressor.MaxRetrievable ();
		uint8_t * buf = payload + DATABASE_STORE_HEADER_SIZE;
		htobe16buf (buf, size); // size
		buf += 2;
		// TODO: check if size doesn't exceed buffer
		compressor.Get (buf, size); 
		m->len += DATABASE_STORE_HEADER_SIZE + 2 + size; // payload size
		FillI2NPMessageHeader (m, eI2NPDatabaseStore);
		
		return m;
	}	

	I2NPMessage * CreateDatabaseStoreMsg (const i2p::data::LeaseSet * leaseSet,  uint32_t replyToken)
	{
		if (!leaseSet) return nullptr;
		I2NPMessage * m = NewI2NPShortMessage ();
		uint8_t * payload = m->GetPayload ();	
		memcpy (payload + DATABASE_STORE_KEY_OFFSET, leaseSet->GetIdentHash (), 32);
		payload[DATABASE_STORE_TYPE_OFFSET] = 1; // LeaseSet
		htobe32buf (payload + DATABASE_STORE_REPLY_TOKEN_OFFSET, replyToken);
		size_t size = DATABASE_STORE_HEADER_SIZE;
		if (replyToken)
		{
			auto leases = leaseSet->GetNonExpiredLeases ();
			if (leases.size () > 0)
			{
				htobe32buf (payload + size, leases[0].tunnelID);
				size += 4; // reply tunnelID
				memcpy (payload + size, leases[0].tunnelGateway, 32);
				size += 32; // reply tunnel gateway
			}
			else
				htobe32buf (payload + DATABASE_STORE_REPLY_TOKEN_OFFSET, 0);
		}
		memcpy (payload + size, leaseSet->GetBuffer (), leaseSet->GetBufferLen ());
		size += leaseSet->GetBufferLen ();
		m->len += size;
		FillI2NPMessageHeader (m, eI2NPDatabaseStore);
		return m;
	}

	I2NPBuildRequestRecordClearText CreateBuildRequestRecord (
		const uint8_t * ourIdent, uint32_t receiveTunnelID, 
	    const uint8_t * nextIdent, uint32_t nextTunnelID, 
	    const uint8_t * layerKey,const uint8_t * ivKey,                                                                 
	    const uint8_t * replyKey, const uint8_t * replyIV, uint32_t nextMessageID,
	          bool isGateway, bool isEndpoint)
	{
		I2NPBuildRequestRecordClearText clearText;	
		clearText.receiveTunnel = htobe32 (receiveTunnelID); 		
		clearText.nextTunnel = htobe32(nextTunnelID);
		memcpy (clearText.layerKey, layerKey, 32);
		memcpy (clearText.ivKey, ivKey, 32);
		memcpy (clearText.replyKey, replyKey, 32);
		memcpy (clearText.replyIV, replyIV, 16);
		clearText.flag = 0;
		if (isGateway) clearText.flag |= 0x80;
		if (isEndpoint) clearText.flag |= 0x40;
		memcpy (clearText.ourIdent, ourIdent, 32);
		memcpy (clearText.nextIdent, nextIdent, 32);
		clearText.requestTime = htobe32 (i2p::util::GetHoursSinceEpoch ()); 
		clearText.nextMessageID = htobe32(nextMessageID);
		return clearText;
	}	

	void EncryptBuildRequestRecord (const i2p::data::RouterInfo& router, 
		const I2NPBuildRequestRecordClearText& clearText, uint8_t * record)
	{
		router.GetElGamalEncryption ()->Encrypt ((uint8_t *)&clearText, sizeof(clearText), record + BUILD_REQUEST_RECORD_ENCRYPTED_OFFSET);
		memcpy (record + BUILD_REQUEST_RECORD_TO_PEER_OFFSET, (const uint8_t *)router.GetIdentHash (), 16);
	}	
	
	bool HandleBuildRequestRecords (int num, uint8_t * records, I2NPBuildRequestRecordClearText& clearText)
	{
		for (int i = 0; i < num; i++)
		{	
			uint8_t * record = records + i*TUNNEL_BUILD_RECORD_SIZE;
			if (!memcmp (record + BUILD_REQUEST_RECORD_TO_PEER_OFFSET, (const uint8_t *)i2p::context.GetRouterInfo ().GetIdentHash (), 16))
			{	
				LogPrint ("Record ",i," is ours");	
			
				i2p::crypto::ElGamalDecrypt (i2p::context.GetEncryptionPrivateKey (), record + BUILD_REQUEST_RECORD_ENCRYPTED_OFFSET, (uint8_t *)&clearText);
				// replace record to reply			
				if (i2p::context.AcceptsTunnels ())
				{	
					i2p::tunnel::TransitTunnel * transitTunnel = 
						i2p::tunnel::CreateTransitTunnel (
							be32toh (clearText.receiveTunnel), 
							clearText.nextIdent, be32toh (clearText.nextTunnel),
							clearText.layerKey, clearText.ivKey, 
							clearText.flag & 0x80, clearText.flag & 0x40);
					i2p::tunnel::tunnels.AddTransitTunnel (transitTunnel);
					record[BUILD_RESPONSE_RECORD_RET_OFFSET] = 0;
				}
				else
					record[BUILD_RESPONSE_RECORD_RET_OFFSET] = 30; // always reject with bandwidth reason (30)
				
				//TODO: fill filler
				CryptoPP::SHA256().CalculateDigest(record + BUILD_RESPONSE_RECORD_HASH_OFFSET, 
					record + BUILD_RESPONSE_RECORD_PADDING_OFFSET, BUILD_RESPONSE_RECORD_PADDING_SIZE + 1); // + 1 byte of ret
				// encrypt reply
				i2p::crypto::CBCEncryption encryption;
				for (int j = 0; j < num; j++)
				{
					encryption.SetKey (clearText.replyKey);
					encryption.SetIV (clearText.replyIV);
					uint8_t * reply = records + j*TUNNEL_BUILD_RECORD_SIZE;
					encryption.Encrypt(reply, TUNNEL_BUILD_RECORD_SIZE, reply); 
				}
				return true;
			}	
		}	
		return false;
	}

	void HandleVariableTunnelBuildMsg (uint32_t replyMsgID, uint8_t * buf, size_t len)
	{	
		int num = buf[0];
		LogPrint ("VariableTunnelBuild ", num, " records");

		i2p::tunnel::Tunnel * tunnel =  i2p::tunnel::tunnels.GetPendingTunnel (replyMsgID);
		if (tunnel)
		{
			// endpoint of inbound tunnel
			LogPrint ("VariableTunnelBuild reply for tunnel ", tunnel->GetTunnelID ());
			if (tunnel->HandleTunnelBuildResponse (buf, len))
			{
				LogPrint ("Inbound tunnel ", tunnel->GetTunnelID (), " has been created");
				tunnel->SetState (i2p::tunnel::eTunnelStateEstablished);	
				i2p::tunnel::tunnels.AddInboundTunnel (static_cast<i2p::tunnel::InboundTunnel *>(tunnel));
			}
			else
			{
				LogPrint ("Inbound tunnel ", tunnel->GetTunnelID (), " has been declined");
				tunnel->SetState (i2p::tunnel::eTunnelStateBuildFailed);	
			}
		}
		else
		{
			I2NPBuildRequestRecordClearText clearText;	
			if (HandleBuildRequestRecords (num, buf + 1, clearText))
			{
				if (clearText.flag & 0x40) // we are endpoint of outboud tunnel
				{
					// so we send it to reply tunnel 
					transports.SendMessage (clearText.nextIdent, 
						CreateTunnelGatewayMsg (be32toh (clearText.nextTunnel),
							eI2NPVariableTunnelBuildReply, buf, len, 
						    be32toh (clearText.nextMessageID)));                         
				}	
				else	
					transports.SendMessage (clearText.nextIdent, 
						CreateI2NPMessage (eI2NPVariableTunnelBuild, buf, len, be32toh (clearText.nextMessageID)));
			}	
		}	
	}

	void HandleTunnelBuildMsg (uint8_t * buf, size_t len)
	{
		I2NPBuildRequestRecordClearText clearText;	
		if (HandleBuildRequestRecords (NUM_TUNNEL_BUILD_RECORDS, buf, clearText))
		{
			if (clearText.flag & 0x40) // we are endpoint of outbound tunnel
			{
				// so we send it to reply tunnel 
				transports.SendMessage (clearText.nextIdent, 
					CreateTunnelGatewayMsg (be32toh (clearText.nextTunnel),
						eI2NPTunnelBuildReply, buf, len, 
					    be32toh (clearText.nextMessageID)));                         
			}	
			else	
				transports.SendMessage (clearText.nextIdent, 
					CreateI2NPMessage (eI2NPTunnelBuild, buf, len, be32toh (clearText.nextMessageID)));
		} 
	}

	void HandleVariableTunnelBuildReplyMsg (uint32_t replyMsgID, uint8_t * buf, size_t len)
	{	
		LogPrint ("VariableTunnelBuildReplyMsg replyMsgID=", replyMsgID);
		i2p::tunnel::Tunnel * tunnel = i2p::tunnel::tunnels.GetPendingTunnel (replyMsgID);
		if (tunnel)
		{	
			// reply for outbound tunnel
			if (tunnel->HandleTunnelBuildResponse (buf, len))
			{	
				LogPrint ("Outbound tunnel ", tunnel->GetTunnelID (), " has been created");
				tunnel->SetState (i2p::tunnel::eTunnelStateEstablished);	
				i2p::tunnel::tunnels.AddOutboundTunnel (static_cast<i2p::tunnel::OutboundTunnel *>(tunnel));
			}	
			else
			{
				LogPrint ("Outbound tunnel ", tunnel->GetTunnelID (), " has been declined");
				tunnel->SetState (i2p::tunnel::eTunnelStateBuildFailed);	
			}
		}	
		else
			LogPrint ("Pending tunnel for message ", replyMsgID, " not found");
	}


	I2NPMessage * CreateTunnelDataMsg (const uint8_t * buf)
	{
		I2NPMessage * msg = NewI2NPMessage ();
		memcpy (msg->GetPayload (), buf, i2p::tunnel::TUNNEL_DATA_MSG_SIZE);
		msg->len += i2p::tunnel::TUNNEL_DATA_MSG_SIZE; 
		FillI2NPMessageHeader (msg, eI2NPTunnelData);
		return msg;
	}	

	I2NPMessage * CreateTunnelDataMsg (uint32_t tunnelID, const uint8_t * payload)	
	{
		I2NPMessage * msg = NewI2NPMessage ();
		memcpy (msg->GetPayload () + 4, payload, i2p::tunnel::TUNNEL_DATA_MSG_SIZE - 4);
		htobe32buf (msg->GetPayload (), tunnelID);
		msg->len += i2p::tunnel::TUNNEL_DATA_MSG_SIZE; 
		FillI2NPMessageHeader (msg, eI2NPTunnelData);
		return msg;
	}	
	
	I2NPMessage * CreateTunnelGatewayMsg (uint32_t tunnelID, const uint8_t * buf, size_t len)
	{
		I2NPMessage * msg = NewI2NPMessage (len);
		uint8_t * payload = msg->GetPayload ();
		htobe32buf (payload + TUNNEL_GATEWAY_HEADER_TUNNELID_OFFSET, tunnelID);
		htobe16buf (payload + TUNNEL_GATEWAY_HEADER_LENGTH_OFFSET, len);
		memcpy (payload + TUNNEL_GATEWAY_HEADER_SIZE, buf, len);
		msg->len += TUNNEL_GATEWAY_HEADER_SIZE + len;
		FillI2NPMessageHeader (msg, eI2NPTunnelGateway);
		return msg;
	}	

	I2NPMessage * CreateTunnelGatewayMsg (uint32_t tunnelID, I2NPMessage * msg)
	{
		if (msg->offset >= I2NP_HEADER_SIZE + TUNNEL_GATEWAY_HEADER_SIZE)
		{
			// message is capable to be used without copying
			uint8_t * payload = msg->GetBuffer () - TUNNEL_GATEWAY_HEADER_SIZE;
			htobe32buf (payload + TUNNEL_GATEWAY_HEADER_TUNNELID_OFFSET, tunnelID);
			int len = msg->GetLength ();
			htobe16buf (payload + TUNNEL_GATEWAY_HEADER_LENGTH_OFFSET, len);
			msg->offset -= (I2NP_HEADER_SIZE + TUNNEL_GATEWAY_HEADER_SIZE);
			msg->len = msg->offset + I2NP_HEADER_SIZE + TUNNEL_GATEWAY_HEADER_SIZE +len;
			FillI2NPMessageHeader (msg, eI2NPTunnelGateway);
			return msg;
		}
		else
		{	
			I2NPMessage * msg1 = CreateTunnelGatewayMsg (tunnelID, msg->GetBuffer (), msg->GetLength ());
			DeleteI2NPMessage (msg);
			return msg1;
		}	                               
	}

	I2NPMessage * CreateTunnelGatewayMsg (uint32_t tunnelID, I2NPMessageType msgType, 
		const uint8_t * buf, size_t len, uint32_t replyMsgID)
	{
		I2NPMessage * msg = NewI2NPMessage (len);
		size_t gatewayMsgOffset = I2NP_HEADER_SIZE + TUNNEL_GATEWAY_HEADER_SIZE;
		msg->offset += gatewayMsgOffset;
		msg->len += gatewayMsgOffset;
		memcpy (msg->GetPayload (), buf, len);
		msg->len += len;
		FillI2NPMessageHeader (msg, msgType, replyMsgID); // create content message
		len = msg->GetLength ();
		msg->offset -= gatewayMsgOffset;
		uint8_t * payload = msg->GetPayload ();
		htobe32buf (payload + TUNNEL_GATEWAY_HEADER_TUNNELID_OFFSET, tunnelID);
		htobe16buf (payload + TUNNEL_GATEWAY_HEADER_LENGTH_OFFSET, len);
		FillI2NPMessageHeader (msg, eI2NPTunnelGateway); // gateway message
		return msg;
	}	
	
	void HandleTunnelGatewayMsg (I2NPMessage * msg)
	{		
		const uint8_t * payload = msg->GetPayload ();
		uint32_t tunnelID = bufbe32toh(payload + TUNNEL_GATEWAY_HEADER_TUNNELID_OFFSET);
		uint16_t len = bufbe16toh(payload + TUNNEL_GATEWAY_HEADER_LENGTH_OFFSET);
		// we make payload as new I2NP message to send
		msg->offset += I2NP_HEADER_SIZE + TUNNEL_GATEWAY_HEADER_SIZE;
		msg->len = msg->offset + len;
		auto typeID = msg->GetTypeID ();
		LogPrint ("TunnelGateway of ", (int)len, " bytes for tunnel ", (unsigned int)tunnelID, ". Msg type ", (int)typeID);
			
		if (typeID == eI2NPDatabaseStore || typeID == eI2NPDatabaseSearchReply)
		{
			// transit DatabaseStore my contain new/updated RI 
			// or DatabaseSearchReply with new routers
			auto ds = NewI2NPMessage ();
			*ds = *msg;
			i2p::data::netdb.PostI2NPMsg (ds);
		}	
		i2p::tunnel::TransitTunnel * tunnel =  i2p::tunnel::tunnels.GetTransitTunnel (tunnelID);
		if (tunnel)
			tunnel->SendTunnelDataMsg (msg);
		else
		{	
			LogPrint ("Tunnel ", (unsigned int)tunnelID, " not found");
			i2p::DeleteI2NPMessage (msg);
		}	
	}	

	size_t GetI2NPMessageLength (const uint8_t * msg)
	{
		return bufbe16toh (msg + I2NP_HEADER_SIZE_OFFSET) + I2NP_HEADER_SIZE;
	}	
	
	void HandleI2NPMessage (uint8_t * msg, size_t len)
	{
		uint8_t typeID = msg[I2NP_HEADER_TYPEID_OFFSET];
		uint32_t msgID = bufbe32toh (msg + I2NP_HEADER_MSGID_OFFSET);	
		LogPrint ("I2NP msg received len=", len,", type=", (int)typeID, ", msgID=", (unsigned int)msgID);

		uint8_t * buf = msg + I2NP_HEADER_SIZE;
		int size = bufbe16toh (msg + I2NP_HEADER_SIZE_OFFSET);
		switch (typeID)
		{	
			case eI2NPVariableTunnelBuild:
				LogPrint ("VariableTunnelBuild");
				HandleVariableTunnelBuildMsg  (msgID, buf, size);
			break;	
			case eI2NPVariableTunnelBuildReply:
				LogPrint ("VariableTunnelBuildReply");
				HandleVariableTunnelBuildReplyMsg (msgID, buf, size);
			break;	
			case eI2NPTunnelBuild:
				LogPrint ("TunnelBuild");
				HandleTunnelBuildMsg  (buf, size);
			break;	
			case eI2NPTunnelBuildReply:
				LogPrint ("TunnelBuildReply");
				// TODO:
			break;	
			default:
				LogPrint ("Unexpected message ", (int)typeID);
		}	
	}

	void HandleI2NPMessage (I2NPMessage * msg)
	{
		if (msg)
		{	
			switch (msg->GetTypeID ())
			{	
				case eI2NPTunnelData:
					LogPrint ("TunnelData");
					i2p::tunnel::tunnels.PostTunnelData (msg);
				break;	
				case eI2NPTunnelGateway:
					LogPrint ("TunnelGateway");
					HandleTunnelGatewayMsg (msg);
				break;
				case eI2NPGarlic:
					LogPrint ("Garlic");
					if (msg->from)
					{
						if (msg->from->GetTunnelPool ())
							msg->from->GetTunnelPool ()->ProcessGarlicMessage (msg);
						else
						{
							LogPrint (eLogInfo, "Local destination for garlic doesn't exist anymore");
							DeleteI2NPMessage (msg);
						}	
					}
					else
						i2p::context.ProcessGarlicMessage (msg); 
				break;
				case eI2NPDatabaseStore:
				case eI2NPDatabaseSearchReply:
				case eI2NPDatabaseLookup:
					// forward to netDb
					i2p::data::netdb.PostI2NPMsg (msg);
				break;
				case eI2NPDeliveryStatus:
					LogPrint ("DeliveryStatus");
					if (msg->from && msg->from->GetTunnelPool ())
						msg->from->GetTunnelPool ()->ProcessDeliveryStatus (msg);
					else
						i2p::context.ProcessDeliveryStatusMessage (msg);
				break;	
				default:
					HandleI2NPMessage (msg->GetBuffer (), msg->GetLength ());
					DeleteI2NPMessage (msg);
			}	
		}	
	}	
}