i2pd/I2NPProtocol.cpp

#include <string.h>
#include <atomic>
#include "I2PEndian.h"
#include <cryptopp/gzip.h>
#include "crypto/ElGamal.h"
#include "util/Timestamp.h"
#include "RouterContext.h"
#include "NetDb.h"
#include "Tunnel.h"
#include "transport/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;
    }   

    std::shared_ptr<I2NPMessage> ToSharedI2NPMessage (I2NPMessage * msg)
    {
        return std::shared_ptr<I2NPMessage>(msg, DeleteI2NPMessage);
    }

    void I2NPMessage::FillI2NPMessageHeader (I2NPMessageType msgType, uint32_t replyMsgID)
    {
        SetTypeID (msgType);
        if (replyMsgID) // for tunnel creation
            SetMsgID (replyMsgID); 
        else    
            SetMsgID (i2p::context.GetRandomNumberGenerator ().GenerateWord32 ());
        SetExpiration (i2p::util::GetMillisecondsSinceEpoch () + 5000); // TODO: 5 secs is a magic number
        UpdateSize ();
        UpdateChks ();
    }       
    
    void I2NPMessage::RenewI2NPMessageHeader ()
    {
        SetMsgID (i2p::context.GetRandomNumberGenerator ().GenerateWord32 ());
        SetExpiration (i2p::util::GetMillisecondsSinceEpoch () + 5000);         
    }

    I2NPMessage * CreateI2NPMessage (I2NPMessageType msgType, const uint8_t * buf, int len, uint32_t replyMsgID)
    {
        I2NPMessage * msg = NewI2NPMessage (len);
        if (msg->len + len < msg->maxLen)
        {
            memcpy (msg->GetPayload (), buf, len);
            msg->len += len;
        }
        else
            LogPrint (eLogError, "I2NP message length ", len, " exceeds max length");
        msg->FillI2NPMessageHeader (msgType, replyMsgID);
        return msg;
    }   

    std::shared_ptr<I2NPMessage> CreateI2NPMessage (const uint8_t * buf, int len, std::shared_ptr<i2p::tunnel::InboundTunnel> from)
    {
        I2NPMessage * msg = NewI2NPMessage ();
        if (msg->offset + len < msg->maxLen)
        {
            memcpy (msg->GetBuffer (), buf, len);
            msg->len = msg->offset + len;
            msg->from = from;
        }
        else
            LogPrint (eLogError, "I2NP message length ", len, " exceeds max length");
        return ToSharedI2NPMessage(msg);
    }   
    
    std::shared_ptr<I2NPMessage> CreateDeliveryStatusMsg (uint32_t msgID)
    {
        I2NPMessage * m = NewI2NPShortMessage ();
        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;
        m->FillI2NPMessageHeader (eI2NPDeliveryStatus);
        return ToSharedI2NPMessage (m);
    }

    std::shared_ptr<I2NPMessage> CreateRouterInfoDatabaseLookupMsg (const uint8_t * key, const uint8_t * from, 
        uint32_t replyTunnelID, bool exploratory, std::set<i2p::data::IdentHash> * excludedPeers)
    {
        auto m =  ToSharedI2NPMessage (excludedPeers ? NewI2NPMessage () : NewI2NPShortMessage ());
        uint8_t * buf = m->GetPayload ();
        memcpy (buf, key, 32); // key
        buf += 32;
        memcpy (buf, from, 32); // from
        buf += 32;
        uint8_t flag = exploratory ? DATABASE_LOOKUP_TYPE_EXPLORATORY_LOOKUP : DATABASE_LOOKUP_TYPE_ROUTERINFO_LOOKUP; 
        if (replyTunnelID)
        {
            *buf = flag | DATABASE_LOOKUP_DELIVERY_FLAG; // set delivery flag
            htobe32buf (buf+1, replyTunnelID);
            buf += 5;
        }
        else
        {   
            *buf = flag; // flag
            buf++;
        }   
                
        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;
        }       
        
        m->len += (buf - m->GetPayload ()); 
        m->FillI2NPMessageHeader (eI2NPDatabaseLookup);
        return m; 
    }   

    std::shared_ptr<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)
    {
        int cnt = excludedFloodfills.size ();
        auto m =  ToSharedI2NPMessage (cnt > 0 ? NewI2NPMessage () : NewI2NPShortMessage ());
        uint8_t * buf = m->GetPayload ();
        memcpy (buf, dest, 32); // key
        buf += 32;
        memcpy (buf, replyTunnel->GetNextIdentHash (), 32); // reply tunnel GW
        buf += 32;
        *buf = DATABASE_LOOKUP_DELIVERY_FLAG | DATABASE_LOOKUP_ENCYPTION_FLAG | DATABASE_LOOKUP_TYPE_LEASESET_LOOKUP; // flags 
        htobe32buf (buf + 1, replyTunnel->GetNextTunnelID ()); // reply tunnel ID
        buf += 5;
        
        // excluded
        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 ()); 
        m->FillI2NPMessageHeader (eI2NPDatabaseLookup);
        return m;                   
    }           

    std::shared_ptr<I2NPMessage> CreateDatabaseSearchReply (const i2p::data::IdentHash& ident, 
         std::vector<i2p::data::IdentHash> routers)
    {
        auto m =  ToSharedI2NPMessage (NewI2NPShortMessage ());
        uint8_t * buf = m->GetPayload ();
        size_t len = 0;
        memcpy (buf, ident, 32);
        len += 32;
        buf[len] = routers.size (); 
        len++;
        for (auto it: routers)
        {
            memcpy (buf + len, it, 32);
            len += 32;
        }   
        memcpy (buf + len, i2p::context.GetRouterInfo ().GetIdentHash (), 32);
        len += 32;  
        m->len += len;
        m->FillI2NPMessageHeader (eI2NPDatabaseSearchReply);
        return m; 
    }   
    
    std::shared_ptr<I2NPMessage> CreateDatabaseStoreMsg (std::shared_ptr<const i2p::data::RouterInfo> router, uint32_t replyToken)
    {
        if (!router) // we send own RouterInfo
            router = context.GetSharedRouterInfo ();

        auto m =  ToSharedI2NPMessage (NewI2NPShortMessage ());
        uint8_t * payload = m->GetPayload ();       

        memcpy (payload + DATABASE_STORE_KEY_OFFSET, router->GetIdentHash (), 32);
        payload[DATABASE_STORE_TYPE_OFFSET] = 0; // RouterInfo
        htobe32buf (payload + DATABASE_STORE_REPLY_TOKEN_OFFSET, replyToken);
        uint8_t * buf = payload + DATABASE_STORE_HEADER_SIZE;
        if (replyToken)
        {
            memset (buf, 0, 4); // zero tunnelID means direct reply
            buf += 4;
            memcpy (buf, router->GetIdentHash (), 32);
            buf += 32;
        }       

        CryptoPP::Gzip compressor;
        compressor.Put (router->GetBuffer (), router->GetBufferLen ());
        compressor.MessageEnd();
        auto size = compressor.MaxRetrievable ();
        htobe16buf (buf, size); // size
        buf += 2;
        m->len += (buf - payload); // payload size
        if (m->len + size > m->maxLen)
        {   
            LogPrint (eLogInfo, "DatabaseStore message size is not enough for ", m->len + size);
            auto newMsg =  ToSharedI2NPMessage (NewI2NPMessage ());
            *newMsg = *m;
            m = newMsg;
            buf = m->buf + m->len;
        }   
        compressor.Get (buf, size); 
        m->len += size;
        m->FillI2NPMessageHeader (eI2NPDatabaseStore);
        
        return m;
    }   

    std::shared_ptr<I2NPMessage> CreateDatabaseStoreMsg (std::shared_ptr<const i2p::data::LeaseSet> leaseSet,  uint32_t replyToken)
    {
        if (!leaseSet) return nullptr;
        auto m =  ToSharedI2NPMessage (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;
        m->FillI2NPMessageHeader (eI2NPDatabaseStore);
        return m;
    }
    
    bool HandleBuildRequestRecords (int num, uint8_t * records, uint8_t * 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, clearText);
                // replace record to reply          
                if (i2p::context.AcceptsTunnels () && 
                    i2p::tunnel::tunnels.GetTransitTunnels ().size () <= MAX_NUM_TRANSIT_TUNNELS &&
                    !i2p::transport::transports.IsBandwidthExceeded ())
                {   
                    i2p::tunnel::TransitTunnel * transitTunnel = 
                        i2p::tunnel::CreateTransitTunnel (
                            bufbe32toh (clearText + BUILD_REQUEST_RECORD_RECEIVE_TUNNEL_OFFSET), 
                            clearText + BUILD_REQUEST_RECORD_NEXT_IDENT_OFFSET, 
                            bufbe32toh (clearText + BUILD_REQUEST_RECORD_NEXT_TUNNEL_OFFSET),
                            clearText + BUILD_REQUEST_RECORD_LAYER_KEY_OFFSET, 
                            clearText + BUILD_REQUEST_RECORD_IV_KEY_OFFSET, 
                            clearText[BUILD_REQUEST_RECORD_FLAG_OFFSET] & 0x80, 
                            clearText[BUILD_REQUEST_RECORD_FLAG_OFFSET ] & 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 + BUILD_REQUEST_RECORD_REPLY_KEY_OFFSET);
                    encryption.SetIV (clearText + BUILD_REQUEST_RECORD_REPLY_IV_OFFSET);
                    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");

        auto tunnel =  i2p::tunnel::tunnels.GetPendingInboundTunnel (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 (tunnel);
            }
            else
            {
                LogPrint ("Inbound tunnel ", tunnel->GetTunnelID (), " has been declined");
                tunnel->SetState (i2p::tunnel::eTunnelStateBuildFailed);    
            }
        }
        else
        {
            uint8_t clearText[BUILD_REQUEST_RECORD_CLEAR_TEXT_SIZE] = {};
            if (HandleBuildRequestRecords (num, buf + 1, clearText))
            {
                if (clearText[BUILD_REQUEST_RECORD_FLAG_OFFSET] & 0x40) // we are endpoint of outboud tunnel
                {
                    // so we send it to reply tunnel 
                    transports.SendMessage (clearText + BUILD_REQUEST_RECORD_NEXT_IDENT_OFFSET, 
                        ToSharedI2NPMessage (CreateTunnelGatewayMsg (bufbe32toh (clearText + BUILD_REQUEST_RECORD_NEXT_TUNNEL_OFFSET),
                            eI2NPVariableTunnelBuildReply, buf, len, 
                            bufbe32toh (clearText + BUILD_REQUEST_RECORD_SEND_MSG_ID_OFFSET))));                         
                }   
                else    
                    transports.SendMessage (clearText + BUILD_REQUEST_RECORD_NEXT_IDENT_OFFSET, 
                        ToSharedI2NPMessage (CreateI2NPMessage (eI2NPVariableTunnelBuild, buf, len, 
                            bufbe32toh (clearText + BUILD_REQUEST_RECORD_SEND_MSG_ID_OFFSET))));
            }   
        }   
    }

    void HandleTunnelBuildMsg (uint8_t * buf, size_t len)
    {
        uint8_t clearText[BUILD_REQUEST_RECORD_CLEAR_TEXT_SIZE];    
        if (HandleBuildRequestRecords (NUM_TUNNEL_BUILD_RECORDS, buf, clearText))
        {
            if (clearText[BUILD_REQUEST_RECORD_FLAG_OFFSET] & 0x40) // we are endpoint of outbound tunnel
            {
                // so we send it to reply tunnel 
                transports.SendMessage (clearText + BUILD_REQUEST_RECORD_NEXT_IDENT_OFFSET, 
                    ToSharedI2NPMessage (CreateTunnelGatewayMsg (bufbe32toh (clearText + BUILD_REQUEST_RECORD_NEXT_TUNNEL_OFFSET),
                        eI2NPTunnelBuildReply, buf, len, 
                        bufbe32toh (clearText + BUILD_REQUEST_RECORD_SEND_MSG_ID_OFFSET))));                         
            }   
            else    
                transports.SendMessage (clearText + BUILD_REQUEST_RECORD_NEXT_IDENT_OFFSET, 
                    ToSharedI2NPMessage (CreateI2NPMessage (eI2NPTunnelBuild, buf, len, 
                        bufbe32toh (clearText + BUILD_REQUEST_RECORD_SEND_MSG_ID_OFFSET))));
        } 
    }

    void HandleVariableTunnelBuildReplyMsg (uint32_t replyMsgID, uint8_t * buf, size_t len)
    {   
        LogPrint ("VariableTunnelBuildReplyMsg replyMsgID=", replyMsgID);
        auto tunnel = i2p::tunnel::tunnels.GetPendingOutboundTunnel (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 (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 = NewI2NPShortMessage ();
        memcpy (msg->GetPayload (), buf, i2p::tunnel::TUNNEL_DATA_MSG_SIZE);
        msg->len += i2p::tunnel::TUNNEL_DATA_MSG_SIZE; 
        msg->FillI2NPMessageHeader (eI2NPTunnelData);
        return msg;
    }   

    I2NPMessage * CreateTunnelDataMsg (uint32_t tunnelID, const uint8_t * payload)  
    {
        I2NPMessage * msg = NewI2NPShortMessage ();
        memcpy (msg->GetPayload () + 4, payload, i2p::tunnel::TUNNEL_DATA_MSG_SIZE - 4);
        htobe32buf (msg->GetPayload (), tunnelID);
        msg->len += i2p::tunnel::TUNNEL_DATA_MSG_SIZE; 
        msg->FillI2NPMessageHeader (eI2NPTunnelData);
        return msg;
    }   

    std::shared_ptr<I2NPMessage> CreateEmptyTunnelDataMsg ()
    {
        I2NPMessage * msg = NewI2NPShortMessage ();
        msg->len += i2p::tunnel::TUNNEL_DATA_MSG_SIZE; 
        return ToSharedI2NPMessage (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;
        msg->FillI2NPMessageHeader (eI2NPTunnelGateway);
        return msg;
    }   

    std::shared_ptr<I2NPMessage> CreateTunnelGatewayMsg (uint32_t tunnelID, std::shared_ptr<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;
            msg->FillI2NPMessageHeader (eI2NPTunnelGateway); 
            return msg;
        }
        else
        {   
            I2NPMessage * msg1 = CreateTunnelGatewayMsg (tunnelID, msg->GetBuffer (), msg->GetLength ());
            return ToSharedI2NPMessage (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;
        msg->FillI2NPMessageHeader (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);
        msg->FillI2NPMessageHeader (eI2NPTunnelGateway); // gateway message
        return 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 (std::shared_ptr<I2NPMessage> msg)
    {
        if (msg)
        {   
            switch (msg->GetTypeID ())
            {   
                case eI2NPTunnelData:
                    LogPrint ("TunnelData");
                    i2p::tunnel::tunnels.PostTunnelData (msg);
                break;  
                case eI2NPTunnelGateway:
                    LogPrint ("TunnelGateway");
                    i2p::tunnel::tunnels.PostTunnelData (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");
                    }
                    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;  
                }
                case eI2NPVariableTunnelBuild:      
                case eI2NPVariableTunnelBuildReply:
                case eI2NPTunnelBuild:
                case eI2NPTunnelBuildReply: 
                    // forward to tunnel thread
                    i2p::tunnel::tunnels.PostTunnelData (msg);
                break;  
                default:
                    HandleI2NPMessage (msg->GetBuffer (), msg->GetLength ());
            }   
        }   
    }   

    I2NPMessagesHandler::~I2NPMessagesHandler ()
    {
        Flush ();
    }
    
    void I2NPMessagesHandler::PutNextMessage (std::shared_ptr<I2NPMessage>  msg)
    {
        if (msg)
        {
            switch (msg->GetTypeID ())
            {   
                case eI2NPTunnelData:
                    m_TunnelMsgs.push_back (msg);
                break;
                case eI2NPTunnelGateway:    
                    m_TunnelGatewayMsgs.push_back (msg);
                break;  
                default:
                    HandleI2NPMessage (msg);
            }       
        }   
    }
    
    void I2NPMessagesHandler::Flush ()
    {
        if (!m_TunnelMsgs.empty ())
        {   
            i2p::tunnel::tunnels.PostTunnelData (m_TunnelMsgs);
            m_TunnelMsgs.clear ();
        }   
        if (!m_TunnelGatewayMsgs.empty ())
        {   
            i2p::tunnel::tunnels.PostTunnelData (m_TunnelGatewayMsgs);
            m_TunnelGatewayMsgs.clear ();
        }   
    }   
}