i2pd/core/Destination.h

#ifndef DESTINATION_H__
#define DESTINATION_H__

#include <thread>
#include <mutex>
#include <memory>
#include <map>
#include <set>
#include <string>
#include <functional>
#include <boost/asio.hpp>
#include "Identity.h"
#include "tunnel/TunnelPool.h"
#include "crypto/CryptoConst.h"
#include "LeaseSet.h"
#include "Garlic.h"
#include "NetDb.h"
#include "Streaming.h"
#include "Datagram.h"

namespace i2p
{
namespace client
{
    const uint8_t PROTOCOL_TYPE_STREAMING = 6;
    const uint8_t PROTOCOL_TYPE_DATAGRAM = 17;
    const uint8_t PROTOCOL_TYPE_RAW = 18;   
    const int PUBLISH_CONFIRMATION_TIMEOUT = 5; // in seconds
    const int LEASESET_REQUEST_TIMEOUT = 5; // in seconds
    const int MAX_LEASESET_REQUEST_TIMEOUT = 40; // in seconds
    const int MAX_NUM_FLOODFILLS_PER_REQUEST = 7;
    const int DESTINATION_CLEANUP_TIMEOUT = 20; // in minutes 
    
    // I2CP
    const char I2CP_PARAM_INBOUND_TUNNEL_LENGTH[] = "inbound.length";
    const int DEFAULT_INBOUND_TUNNEL_LENGTH = 3;
    const char I2CP_PARAM_OUTBOUND_TUNNEL_LENGTH[] = "outbound.length";
    const int DEFAULT_OUTBOUND_TUNNEL_LENGTH = 3;
    const char I2CP_PARAM_INBOUND_TUNNELS_QUANTITY[] = "inbound.quantity";
    const int DEFAULT_INBOUND_TUNNELS_QUANTITY = 5;
    const char I2CP_PARAM_OUTBOUND_TUNNELS_QUANTITY[] = "outbound.quantity";
    const int DEFAULT_OUTBOUND_TUNNELS_QUANTITY = 5;
    const char I2CP_PARAM_EXPLICIT_PEERS[] = "explicitPeers";
    const int STREAM_REQUEST_TIMEOUT = 60; //in seconds

    typedef std::function<void (std::shared_ptr<i2p::stream::Stream> stream)> StreamRequestComplete;

    class ClientDestination: public i2p::garlic::GarlicDestination
    {
        typedef std::function<void (std::shared_ptr<i2p::data::LeaseSet> leaseSet)> RequestComplete;
        // leaseSet = nullptr means not found
        struct LeaseSetRequest
        {
            LeaseSetRequest (boost::asio::io_service& service): requestTime (0), requestTimeoutTimer (service) {};
            std::set<i2p::data::IdentHash> excluded;
            uint64_t requestTime;
            boost::asio::deadline_timer requestTimeoutTimer;
            RequestComplete requestComplete;
        };  
        
        
        public:

            ClientDestination (const i2p::data::PrivateKeys& keys, bool isPublic, const std::map<std::string, std::string> * params = nullptr);
            ~ClientDestination ();  

            virtual void Start ();
            virtual void Stop ();
            bool IsRunning () const { return m_IsRunning; };
            boost::asio::io_service& GetService () { return m_Service; };
            std::shared_ptr<i2p::tunnel::TunnelPool> GetTunnelPool () { return m_Pool; }; 
            bool IsReady () const { return m_LeaseSet && m_LeaseSet->HasNonExpiredLeases () && m_Pool->GetOutboundTunnels ().size () > 0; };
            std::shared_ptr<const i2p::data::LeaseSet> FindLeaseSet (const i2p::data::IdentHash& ident);
            bool RequestDestination (const i2p::data::IdentHash& dest, RequestComplete requestComplete = nullptr);
            
            // streaming
            std::shared_ptr<i2p::stream::StreamingDestination> CreateStreamingDestination (int port); // additional
            std::shared_ptr<i2p::stream::StreamingDestination> GetStreamingDestination (int port = 0) const;
            // following methods operate with default streaming destination
            void CreateStream (StreamRequestComplete streamRequestComplete, const i2p::data::IdentHash& dest, int port = 0);
            std::shared_ptr<i2p::stream::Stream> CreateStream (std::shared_ptr<const i2p::data::LeaseSet> remote, int port = 0);
            void AcceptStreams (const i2p::stream::StreamingDestination::Acceptor& acceptor);
            void StopAcceptingStreams ();
            bool IsAcceptingStreams () const;
            
            // datagram
            i2p::datagram::DatagramDestination * GetDatagramDestination () const { return m_DatagramDestination; };
            i2p::datagram::DatagramDestination * CreateDatagramDestination ();

            // implements LocalDestination
            const i2p::data::PrivateKeys& GetPrivateKeys () const { return m_Keys; };
            const uint8_t * GetEncryptionPrivateKey () const { return m_EncryptionPrivateKey; };
            const uint8_t * GetEncryptionPublicKey () const { return m_EncryptionPublicKey; };
            
            // implements GarlicDestination
            std::shared_ptr<const i2p::data::LeaseSet> GetLeaseSet ();
            std::shared_ptr<i2p::tunnel::TunnelPool> GetTunnelPool () const { return m_Pool; }
            void HandleI2NPMessage (const uint8_t * buf, size_t len, std::shared_ptr<i2p::tunnel::InboundTunnel> from);

            // override GarlicDestination
            bool SubmitSessionKey (const uint8_t * key, const uint8_t * tag);
            void ProcessGarlicMessage (std::shared_ptr<I2NPMessage> msg);
            void ProcessDeliveryStatusMessage (std::shared_ptr<I2NPMessage> msg);   
            void SetLeaseSetUpdated ();

            // I2CP
            void HandleDataMessage (const uint8_t * buf, size_t len);

        private:
                
            void Run ();            
            void UpdateLeaseSet ();
            void Publish ();
            void HandlePublishConfirmationTimer (const boost::system::error_code& ecode);
            void HandleDatabaseStoreMessage (const uint8_t * buf, size_t len);
            void HandleDatabaseSearchReplyMessage (const uint8_t * buf, size_t len);
            void HandleDeliveryStatusMessage (std::shared_ptr<I2NPMessage> msg);        

            void RequestLeaseSet (const i2p::data::IdentHash& dest, RequestComplete requestComplete);
            bool SendLeaseSetRequest (const i2p::data::IdentHash& dest, std::shared_ptr<const i2p::data::RouterInfo>  nextFloodfill, LeaseSetRequest * request);    
            void HandleRequestTimoutTimer (const boost::system::error_code& ecode, const i2p::data::IdentHash& dest);
            void HandleCleanupTimer (const boost::system::error_code& ecode);
            void CleanupRemoteLeaseSets ();
            
        private:

            volatile bool m_IsRunning;
            std::thread * m_Thread; 
            boost::asio::io_service m_Service;
            boost::asio::io_service::work m_Work;
            i2p::data::PrivateKeys m_Keys;
            uint8_t m_EncryptionPublicKey[256], m_EncryptionPrivateKey[256];
            std::map<i2p::data::IdentHash, std::shared_ptr<i2p::data::LeaseSet> > m_RemoteLeaseSets;
            std::map<i2p::data::IdentHash, LeaseSetRequest *> m_LeaseSetRequests;

            std::shared_ptr<i2p::tunnel::TunnelPool> m_Pool;
            std::shared_ptr<i2p::data::LeaseSet> m_LeaseSet;
            bool m_IsPublic;
            uint32_t m_PublishReplyToken;
            std::set<i2p::data::IdentHash> m_ExcludedFloodfills; // for publishing
            
            std::shared_ptr<i2p::stream::StreamingDestination> m_StreamingDestination; // default
            std::map<uint16_t, std::shared_ptr<i2p::stream::StreamingDestination> > m_StreamingDestinationsByPorts;
            i2p::datagram::DatagramDestination * m_DatagramDestination;
    
            boost::asio::deadline_timer m_PublishConfirmationTimer, m_CleanupTimer;

        public:
            
            // for HTTP only
            int GetNumRemoteLeaseSets () const { return m_RemoteLeaseSets.size (); };
    };  
}   
}   

#endif