tcp-socket-base.h

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/*
 * Copyright (c) 2007 Georgia Tech Research Corporation
 * Copyright (c) 2010 Adrian Sai-wah Tam
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation;
 *
 * 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, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * Author: Adrian Sai-wah Tam <adrian.sw.tam@gmail.com>
 */
#ifndef TCP_SOCKET_BASE_H
#define TCP_SOCKET_BASE_H
 
#include "ns3/data-rate.h"
#include "ns3/ipv4-header.h"
#include "ns3/ipv6-header.h"
#include "ns3/node.h"
#include "ns3/sequence-number.h"
#include "ns3/tcp-socket-state.h"
#include "ns3/tcp-socket.h"
#include "ns3/timer.h"
#include "ns3/traced-value.h"
 
#include <queue>
#include <stdint.h>
 
namespace ns3
{
 
class Ipv4EndPoint;
class Ipv6EndPoint;
class Node;
class Packet;
class TcpL4Protocol;
class TcpHeader;
class TcpCongestionOps;
class TcpRecoveryOps;
class RttEstimator;
class TcpRxBuffer;
class TcpTxBuffer;
class TcpOption;
class Ipv4Interface;
class Ipv6Interface;
class TcpRateOps;
 
class RttHistory
{
  public:
    RttHistory(SequenceNumber32 s, uint32_t c, Time t);
    RttHistory(const RttHistory& h); // Copy constructor
  public:
    SequenceNumber32 seq; 
    uint32_t count;       
    Time time;            
    bool retx;            
};
 
class TcpSocketBase : public TcpSocket
{
  public:
    static TypeId GetTypeId();
 
    TypeId GetInstanceTypeId() const override;
 
    friend class TcpGeneralTest;
 
    TcpSocketBase();
 
    TcpSocketBase(const TcpSocketBase& sock);
    ~TcpSocketBase() override;
 
    // Set associated Node, TcpL4Protocol, RttEstimator to this socket
 
    virtual void SetNode(Ptr<Node> node);
 
    virtual void SetTcp(Ptr<TcpL4Protocol> tcp);
 
    virtual void SetRtt(Ptr<RttEstimator> rtt);
 
    void SetMinRto(Time minRto);
 
    Time GetMinRto() const;
 
    void SetClockGranularity(Time clockGranularity);
 
    Time GetClockGranularity() const;
 
    Ptr<TcpTxBuffer> GetTxBuffer() const;
 
    Ptr<TcpRxBuffer> GetRxBuffer() const;
 
    void SetRetxThresh(uint32_t retxThresh);
 
    uint32_t GetRetxThresh() const
    {
        return m_retxThresh;
    }
 
    TracedCallback<DataRate, DataRate> m_pacingRateTrace;
 
    TracedCallback<uint32_t, uint32_t> m_cWndTrace;
 
    TracedCallback<uint32_t, uint32_t> m_cWndInflTrace;
 
    TracedCallback<uint32_t, uint32_t> m_ssThTrace;
 
    TracedCallback<TcpSocketState::TcpCongState_t, TcpSocketState::TcpCongState_t> m_congStateTrace;
 
    TracedCallback<TcpSocketState::EcnState_t, TcpSocketState::EcnState_t> m_ecnStateTrace;
 
    TracedCallback<SequenceNumber32, SequenceNumber32> m_highTxMarkTrace;
 
    TracedCallback<SequenceNumber32, SequenceNumber32> m_nextTxSequenceTrace;
 
    TracedCallback<uint32_t, uint32_t> m_bytesInFlightTrace;
 
    TracedCallback<Time, Time> m_lastRttTrace;
 
    void UpdatePacingRateTrace(DataRate oldValue, DataRate newValue) const;
 
    void UpdateCwnd(uint32_t oldValue, uint32_t newValue) const;
 
    void UpdateCwndInfl(uint32_t oldValue, uint32_t newValue) const;
 
    void UpdateSsThresh(uint32_t oldValue, uint32_t newValue) const;
 
    void UpdateCongState(TcpSocketState::TcpCongState_t oldValue,
                         TcpSocketState::TcpCongState_t newValue) const;
 
    void UpdateEcnState(TcpSocketState::EcnState_t oldValue,
                        TcpSocketState::EcnState_t newValue) const;
 
    void UpdateHighTxMark(SequenceNumber32 oldValue, SequenceNumber32 newValue) const;
 
    void UpdateNextTxSequence(SequenceNumber32 oldValue, SequenceNumber32 newValue) const;
 
    void UpdateBytesInFlight(uint32_t oldValue, uint32_t newValue) const;
 
    void UpdateRtt(Time oldValue, Time newValue) const;
 
    void SetCongestionControlAlgorithm(Ptr<TcpCongestionOps> algo);
 
    void SetRecoveryAlgorithm(Ptr<TcpRecoveryOps> recovery);
 
    inline uint8_t MarkEcnEct0(uint8_t tos) const
    {
        return ((tos & 0xfc) | 0x02);
    }
 
    inline uint8_t MarkEcnEct1(uint8_t tos) const
    {
        return ((tos & 0xfc) | 0x01);
    }
 
    inline uint8_t MarkEcnCe(uint8_t tos) const
    {
        return ((tos & 0xfc) | 0x03);
    }
 
    inline uint8_t ClearEcnBits(uint8_t tos) const
    {
        return tos & 0xfc;
    }
 
    inline bool CheckNoEcn(uint8_t tos) const
    {
        return ((tos & 0x03) == 0x00);
    }
 
    inline bool CheckEcnEct0(uint8_t tos) const
    {
        return ((tos & 0x03) == 0x02);
    }
 
    inline bool CheckEcnEct1(uint8_t tos) const
    {
        return ((tos & 0x03) == 0x01);
    }
 
    inline bool CheckEcnCe(uint8_t tos) const
    {
        return ((tos & 0x03) == 0x03);
    }
 
    inline uint8_t MarkEcnCodePoint(const uint8_t tos,
                                    const TcpSocketState::EcnCodePoint_t codePoint) const
    {
        return ((tos & 0xfc) | codePoint);
    }
 
    void SetUseEcn(TcpSocketState::UseEcn_t useEcn);
 
    void SetPacingStatus(bool pacing);
 
    void SetPaceInitialWindow(bool paceWindow);
 
    // Necessary implementations of null functions from ns3::Socket
    SocketErrno GetErrno() const override;     // returns m_errno
    SocketType GetSocketType() const override; // returns socket type
    Ptr<Node> GetNode() const override;        // returns m_node
    int Bind() override;  // Bind a socket by setting up endpoint in TcpL4Protocol
    int Bind6() override; // Bind a socket by setting up endpoint in TcpL4Protocol
    int Bind(const Address& address) override; // ... endpoint of specific addr or port
    int Connect(
        const Address& address) override; // Setup endpoint and call ProcessAction() to connect
    int Listen()
        override; // Verify the socket is in a correct state and call ProcessAction() to listen
    int Close() override;        // Close by app: Kill socket upon tx buffer emptied
    int ShutdownSend() override; // Assert the m_shutdownSend flag to prevent send to network
    int ShutdownRecv() override; // Assert the m_shutdownRecv flag to prevent forward to app
    int Send(Ptr<Packet> p, uint32_t flags) override; // Call by app to send data to network
    int SendTo(Ptr<Packet> p,
               uint32_t flags,
               const Address& toAddress) override; // Same as Send(), toAddress is insignificant
    Ptr<Packet> Recv(uint32_t maxSize,
                     uint32_t flags) override; // Return a packet to be forwarded to app
    Ptr<Packet> RecvFrom(uint32_t maxSize, uint32_t flags, Address& fromAddress)
        override;                             // ... and write the remote address at fromAddress
    uint32_t GetTxAvailable() const override; // Available Tx buffer size
    uint32_t GetRxAvailable()
        const override; // Available-to-read data size, i.e. value of m_rxAvailable
    int GetSockName(Address& address) const override; // Return local addr:port in address
    int GetPeerName(Address& address) const override;
    void BindToNetDevice(Ptr<NetDevice> netdevice) override; // NetDevice with my m_endPoint
 
    typedef void (*TcpTxRxTracedCallback)(const Ptr<const Packet> packet,
                                          const TcpHeader& header,
                                          const Ptr<const TcpSocketBase> socket);
 
  protected:
    // Implementing ns3::TcpSocket -- Attribute get/set
    // inherited, no need to doc
 
    void SetSndBufSize(uint32_t size) override;
    uint32_t GetSndBufSize() const override;
    void SetRcvBufSize(uint32_t size) override;
    uint32_t GetRcvBufSize() const override;
    void SetSegSize(uint32_t size) override;
    uint32_t GetSegSize() const override;
    void SetInitialSSThresh(uint32_t threshold) override;
    uint32_t GetInitialSSThresh() const override;
    void SetInitialCwnd(uint32_t cwnd) override;
    uint32_t GetInitialCwnd() const override;
    void SetConnTimeout(Time timeout) override;
    Time GetConnTimeout() const override;
    void SetSynRetries(uint32_t count) override;
    uint32_t GetSynRetries() const override;
    void SetDataRetries(uint32_t retries) override;
    uint32_t GetDataRetries() const override;
    void SetDelAckTimeout(Time timeout) override;
    Time GetDelAckTimeout() const override;
    void SetDelAckMaxCount(uint32_t count) override;
    uint32_t GetDelAckMaxCount() const override;
    void SetTcpNoDelay(bool noDelay) override;
    bool GetTcpNoDelay() const override;
    void SetPersistTimeout(Time timeout) override;
    Time GetPersistTimeout() const override;
    bool SetAllowBroadcast(bool allowBroadcast) override;
    bool GetAllowBroadcast() const override;
 
    // Helper functions: Connection set up
 
    int SetupCallback();
 
    int DoConnect();
 
    void ConnectionSucceeded();
 
    int SetupEndpoint();
 
    int SetupEndpoint6();
 
    virtual void CompleteFork(Ptr<Packet> p,
                              const TcpHeader& tcpHeader,
                              const Address& fromAddress,
                              const Address& toAddress);
 
    // Helper functions: Transfer operation
 
    bool IsValidTcpSegment(const SequenceNumber32 seq,
                           const uint32_t tcpHeaderSize,
                           const uint32_t tcpPayloadSize);
 
    void ForwardUp(Ptr<Packet> packet,
                   Ipv4Header header,
                   uint16_t port,
                   Ptr<Ipv4Interface> incomingInterface);
 
    void ForwardUp6(Ptr<Packet> packet,
                    Ipv6Header header,
                    uint16_t port,
                    Ptr<Ipv6Interface> incomingInterface);
 
    virtual void DoForwardUp(Ptr<Packet> packet,
                             const Address& fromAddress,
                             const Address& toAddress);
 
    void ForwardIcmp(Ipv4Address icmpSource,
                     uint8_t icmpTtl,
                     uint8_t icmpType,
                     uint8_t icmpCode,
                     uint32_t icmpInfo);
 
    void ForwardIcmp6(Ipv6Address icmpSource,
                      uint8_t icmpTtl,
                      uint8_t icmpType,
                      uint8_t icmpCode,
                      uint32_t icmpInfo);
 
    uint32_t SendPendingData(bool withAck = false);
 
    virtual uint32_t SendDataPacket(SequenceNumber32 seq, uint32_t maxSize, bool withAck);
 
    virtual void SendEmptyPacket(uint8_t flags);
 
    void SendRST();
 
    bool OutOfRange(SequenceNumber32 head, SequenceNumber32 tail) const;
 
    // Helper functions: Connection close
 
    int DoClose();
 
    void CloseAndNotify();
 
    void Destroy();
 
    void Destroy6();
 
    void DeallocateEndPoint();
 
    void PeerClose(Ptr<Packet> p, const TcpHeader& tcpHeader);
 
    void DoPeerClose();
 
    void CancelAllTimers();
 
    void TimeWait();
 
    // State transition functions
 
    void ProcessEstablished(Ptr<Packet> packet,
                            const TcpHeader& tcpHeader); // Received a packet upon ESTABLISHED state
 
    void ProcessListen(Ptr<Packet> packet,
                       const TcpHeader& tcpHeader,
                       const Address& fromAddress,
                       const Address& toAddress);
 
    void ProcessSynSent(Ptr<Packet> packet, const TcpHeader& tcpHeader);
 
    void ProcessSynRcvd(Ptr<Packet> packet,
                        const TcpHeader& tcpHeader,
                        const Address& fromAddress,
                        const Address& toAddress);
 
    void ProcessWait(Ptr<Packet> packet, const TcpHeader& tcpHeader);
 
    void ProcessClosing(Ptr<Packet> packet, const TcpHeader& tcpHeader);
 
    void ProcessLastAck(Ptr<Packet> packet, const TcpHeader& tcpHeader);
 
    // Window management
 
    virtual uint32_t UnAckDataCount() const;
 
    virtual uint32_t BytesInFlight() const;
 
    virtual uint32_t Window() const;
 
    virtual uint32_t AvailableWindow() const;
 
    virtual uint16_t AdvertisedWindowSize(bool scale = true) const;
 
    void UpdateWindowSize(const TcpHeader& header);
 
    // Manage data tx/rx
 
    virtual Ptr<TcpSocketBase> Fork();
 
    virtual void ReceivedAck(Ptr<Packet> packet, const TcpHeader& tcpHeader);
 
    virtual void ProcessAck(const SequenceNumber32& ackNumber,
                            bool scoreboardUpdated,
                            uint32_t currentDelivered,
                            const SequenceNumber32& oldHeadSequence);
 
    virtual void ReceivedData(Ptr<Packet> packet, const TcpHeader& tcpHeader);
 
    virtual void EstimateRtt(const TcpHeader& tcpHeader);
 
    virtual void UpdateRttHistory(const SequenceNumber32& seq, uint32_t sz, bool isRetransmission);
 
    virtual void NewAck(const SequenceNumber32& seq, bool resetRTO);
 
    void DupAck(uint32_t currentDelivered);
 
    void EnterCwr(uint32_t currentDelivered);
 
    void EnterRecovery(uint32_t currentDelivered);
 
    virtual void ReTxTimeout();
 
    virtual void DelAckTimeout();
 
    virtual void LastAckTimeout();
 
    virtual void PersistTimeout();
 
    void DoRetransmit();
 
    void AddOptions(TcpHeader& tcpHeader);
 
    void ReadOptions(const TcpHeader& tcpHeader, uint32_t* bytesSacked);
 
    bool IsTcpOptionEnabled(uint8_t kind) const;
 
    void ProcessOptionWScale(const Ptr<const TcpOption> option);
    void AddOptionWScale(TcpHeader& header);
 
    uint8_t CalculateWScale() const;
 
    void ProcessOptionSackPermitted(const Ptr<const TcpOption> option);
 
    uint32_t ProcessOptionSack(const Ptr<const TcpOption> option);
 
    void AddOptionSackPermitted(TcpHeader& header);
 
    void AddOptionSack(TcpHeader& header);
 
    void ProcessOptionTimestamp(const Ptr<const TcpOption> option, const SequenceNumber32& seq);
    void AddOptionTimestamp(TcpHeader& header);
 
    static uint32_t SafeSubtraction(uint32_t a, uint32_t b);
 
    void NotifyPacingPerformed();
 
    bool IsPacingEnabled() const;
 
    void UpdatePacingRate();
 
    void AddSocketTags(const Ptr<Packet>& p) const;
 
    uint32_t GetRWnd() const;
 
    SequenceNumber32 GetHighRxAck() const;
 
  protected:
    // Counters and events
    EventId m_retxEvent{};     
    EventId m_lastAckEvent{};  
    EventId m_delAckEvent{};   
    EventId m_persistEvent{};  
    EventId m_timewaitEvent{}; 
 
    // ACK management
    uint32_t m_dupAckCount{0};    
    uint32_t m_delAckCount{0};    
    uint32_t m_delAckMaxCount{0}; 
 
    // Nagle algorithm
    bool m_noDelay{false}; 
 
    // Retries
    uint32_t m_synCount{0};      
    uint32_t m_synRetries{0};    
    uint32_t m_dataRetrCount{0}; 
    uint32_t m_dataRetries{0};   
 
    // Timeouts
    TracedValue<Time> m_rto{Seconds(0.0)};   
    Time m_minRto{Time::Max()};              
    Time m_clockGranularity{Seconds(0.001)}; 
    Time m_delAckTimeout{Seconds(0.0)};      
    Time m_persistTimeout{Seconds(0.0)};     
    Time m_cnTimeout{Seconds(0.0)};          
 
    // History of RTT
    std::deque<RttHistory> m_history; 
 
    // Connections to other layers of TCP/IP
    Ipv4EndPoint* m_endPoint{nullptr};  
    Ipv6EndPoint* m_endPoint6{nullptr}; 
    Ptr<Node> m_node;                   
    Ptr<TcpL4Protocol> m_tcp;           
    Callback<void, Ipv4Address, uint8_t, uint8_t, uint8_t, uint32_t>
        m_icmpCallback; 
    Callback<void, Ipv6Address, uint8_t, uint8_t, uint8_t, uint32_t>
        m_icmpCallback6; 
 
    Ptr<RttEstimator> m_rtt; 
 
    // Tx buffer management
    Ptr<TcpTxBuffer> m_txBuffer; 
 
    // State-related attributes
    TracedValue<TcpStates_t> m_state{CLOSED}; 
 
    mutable SocketErrno m_errno{ERROR_NOTERROR}; 
 
    bool m_closeNotified{false}; 
    bool m_closeOnEmpty{false};  
    bool m_shutdownSend{false};  
    bool m_shutdownRecv{false};  
    bool m_connected{false};     
    double m_msl{0.0};           
 
    // Window management
    uint16_t m_maxWinSize{0};                         
    uint32_t m_bytesAckedNotProcessed{0};             
    SequenceNumber32 m_highTxAck{0};                  
    TracedValue<uint32_t> m_rWnd{0};                  
    TracedValue<uint32_t> m_advWnd{0};                
    TracedValue<SequenceNumber32> m_highRxMark{0};    
    TracedValue<SequenceNumber32> m_highRxAckMark{0}; 
 
    // Options
    bool m_sackEnabled{true};       
    bool m_winScalingEnabled{true}; 
    uint8_t m_rcvWindShift{0};      
    uint8_t m_sndWindShift{0};      
    bool m_timestampEnabled{true};  
    uint32_t m_timestampToEcho{0};  
 
    EventId m_sendPendingDataEvent{}; 
 
    // Fast Retransmit and Recovery
    SequenceNumber32 m_recover{
        0}; 
    bool m_recoverActive{false}; 
    uint32_t m_retxThresh{3};    
    bool m_limitedTx{true};      
 
    // Transmission Control Block
    Ptr<TcpSocketState> m_tcb;                 
    Ptr<TcpCongestionOps> m_congestionControl; 
    Ptr<TcpRecoveryOps> m_recoveryOps;         
    Ptr<TcpRateOps> m_rateOps;                 
 
    // Guesses over the other connection end
    bool m_isFirstPartialAck{true}; 
 
    // The following two traces pass a packet with a TCP header
    TracedCallback<Ptr<const Packet>,
                   const TcpHeader&,
                   Ptr<const TcpSocketBase>>
        m_txTrace; 
 
    TracedCallback<Ptr<const Packet>,
                   const TcpHeader&,
                   Ptr<const TcpSocketBase>>
        m_rxTrace; 
 
    // Pacing related variable
    Timer m_pacingTimer{Timer::CANCEL_ON_DESTROY}; 
 
    // Parameters related to Explicit Congestion Notification
    TracedValue<SequenceNumber32> m_ecnEchoSeq{
        0}; 
    TracedValue<SequenceNumber32> m_ecnCESeq{
        0}; 
    TracedValue<SequenceNumber32> m_ecnCWRSeq{0}; 
};
 
typedef void (*TcpCongStatesTracedValueCallback)(const TcpSocketState::TcpCongState_t oldValue,
                                                 const TcpSocketState::TcpCongState_t newValue);
 
typedef void (*EcnStatesTracedValueCallback)(const TcpSocketState::EcnState_t oldValue,
                                             const TcpSocketState::EcnState_t newValue);
 
} // namespace ns3
 
#endif /* TCP_SOCKET_BASE_H */