/* -*- Mode: C++; c-file-style: "gnu"; indent-tabs-mode:nil; -*- */
/*
* Copyright (c) 2007 Georgia Tech Research Corporation
*
* 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: Raj Bhattacharjea <raj.b@gatech.edu>
*/
#ifndef TCP_SOCKET_IMPL_H
#define TCP_SOCKET_IMPL_H
#include <stdint.h>
#include <queue>
#include "ns3/callback.h"
#include "ns3/traced-value.h"
#include "ns3/tcp-socket.h"
#include "ns3/ptr.h"
#include "ns3/ipv4-address.h"
#include "ns3/event-id.h"
#include "tcp-typedefs.h"
#include "pending-data.h"
#include "sequence-number.h"
#include "rtt-estimator.h"
namespace ns3 {
class Ipv4EndPoint;
class Node;
class Packet;
class TcpL4Protocol;
class TcpHeader;
/**
* \ingroup socket
* \ingroup tcp
*
* \brief An implementation of a stream socket using TCP.
*
* This class contains an implementation of TCP Tahoe, as well as a sockets
* interface for talking to TCP. Features include connection orientation,
* reliability through cumulative acknowledgements, congestion and flow
* control. Finite send buffer semantics are modeled, but as of yet, finite
* receive buffer modelling is unimplemented.
*
* The closedown of these sockets is as of yet not compliant with the relevent
* RFCs, i.e. the FIN handshaking isn't correct. While this is visible at the
* PCAP tracing level, it has no effect on the statistics users are interested
* in, i.e. throughput, delay, etc. of actual payload data.
*
* Asynchronous callbacks to provide notifications to higher layers that a
* protocol event has occured, such as space freeing up in the send buffer
* or new data arriving in the receive buffer.
*/
class TcpSocketImpl : public TcpSocket
{
public:
static TypeId GetTypeId (void);
/**
* Create an unbound tcp socket.
*/
TcpSocketImpl ();
TcpSocketImpl (const TcpSocketImpl& sock);
virtual ~TcpSocketImpl ();
void SetNode (Ptr<Node> node);
void SetTcp (Ptr<TcpL4Protocol> tcp);
void SetRtt (Ptr<RttEstimator> rtt);
virtual enum SocketErrno GetErrno (void) const;
virtual Ptr<Node> GetNode (void) const;
virtual int Bind (void);
virtual int Bind (const Address &address);
virtual int Close (void);
virtual int ShutdownSend (void);
virtual int ShutdownRecv (void);
virtual int Connect(const Address &address);
virtual int Listen(void);
virtual uint32_t GetTxAvailable (void) const;
virtual int Send (Ptr<Packet> p, uint32_t flags);
virtual int SendTo(Ptr<Packet> p, uint32_t flags, const Address &toAddress);
virtual uint32_t GetRxAvailable (void) const;
virtual Ptr<Packet> Recv (uint32_t maxSize, uint32_t flags);
virtual Ptr<Packet> RecvFrom (uint32_t maxSize, uint32_t flags,
Address &fromAddress);
virtual int GetSockName (Address &address) const;
virtual void BindToNetDevice (Ptr<NetDevice> netdevice);
private:
friend class Tcp;
// invoked by Tcp class
int FinishBind (void);
void ForwardUp (Ptr<Packet> p, Ipv4Address saddr, Ipv4Address daddr, uint16_t port);
void Destroy (void);
int DoSendTo (Ptr<Packet> p, const Address &daddr);
int DoSendTo (Ptr<Packet> p, Ipv4Address daddr, uint16_t dport);
void SendEmptyPacket(uint8_t flags);
void SendRST();
//methods for state
bool ProcessAction (Actions_t a);
bool ProcessAction (Actions_t a, const TcpHeader& tcpHeader,
Ipv4Address saddr, Ipv4Address daddr);
bool ProcessPacketAction (Actions_t a, Ptr<Packet> p,
const TcpHeader& tcpHeader,
const Address& fromAddress,
const Address& toAddress);
Actions_t ProcessEvent (Events_t e);
bool SendPendingData(bool withAck = false);
void CompleteFork(Ptr<Packet>, const TcpHeader&, const Address& fromAddress, const Address& toAddress);
void ConnectionSucceeded();
//methods for window management
virtual uint32_t UnAckDataCount(); // Return count of number of unacked bytes
virtual uint32_t BytesInFlight(); // Return total bytes in flight
virtual uint32_t Window(); // Return window size (integer)
virtual uint32_t AvailableWindow();// Return unfilled portion of window
//methods for Rx buffer management
uint32_t RxBufferFreeSpace();
uint16_t AdvertisedWindowSize();
// Manage data tx/rx
void NewRx (Ptr<Packet>, const TcpHeader&, const Address& fromAddress, const Address& toAddress);
void RxBufFinishInsert (SequenceNumber);
Ptr<TcpSocketImpl> Copy ();
virtual void NewAck (SequenceNumber seq);
virtual void DupAck (const TcpHeader& t, uint32_t count);
virtual void ReTxTimeout ();
void DelAckTimeout ();
void LastAckTimeout ();
void PersistTimeout ();
void Retransmit ();
void CommonNewAck (SequenceNumber seq, bool skipTimer = false);
// All timers are cancelled when the endpoint is deleted, to insure
// we don't have additional activity
void CancelAllTimers();
// attribute related
virtual void SetSndBufSize (uint32_t size);
virtual uint32_t GetSndBufSize (void) const;
virtual void SetRcvBufSize (uint32_t size);
virtual uint32_t GetRcvBufSize (void) const;
virtual void SetSegSize (uint32_t size);
virtual uint32_t GetSegSize (void) const;
virtual void SetSSThresh (uint32_t threshold);
virtual uint32_t GetSSThresh (void) const;
virtual void SetInitialCwnd (uint32_t cwnd);
virtual uint32_t GetInitialCwnd (void) const;
virtual void SetConnTimeout (Time timeout);
virtual Time GetConnTimeout (void) const;
virtual void SetConnCount (uint32_t count);
virtual uint32_t GetConnCount (void) const;
virtual void SetDelAckTimeout (Time timeout);
virtual Time GetDelAckTimeout (void) const;
virtual void SetDelAckMaxCount (uint32_t count);
virtual uint32_t GetDelAckMaxCount (void) const;
bool m_skipRetxResched;
uint32_t m_dupAckCount;
EventId m_retxEvent;
EventId m_lastAckEvent;
EventId m_delAckEvent;
uint32_t m_delAckCount;
uint32_t m_delAckMaxCount;
Time m_delAckTimeout;
Ipv4EndPoint *m_endPoint;
Ptr<Node> m_node;
Ptr<TcpL4Protocol> m_tcp;
enum SocketErrno m_errno;
bool m_shutdownSend;
bool m_shutdownRecv;
bool m_connected;
//manage the state infomation
States_t m_state;
bool m_closeNotified;
bool m_closeRequestNotified;
bool m_closeOnEmpty;
bool m_pendingClose;
//sequence info, sender side
SequenceNumber m_nextTxSequence;
SequenceNumber m_highTxMark;
SequenceNumber m_highestRxAck;
SequenceNumber m_lastRxAck;
//sequence info, reciever side
SequenceNumber m_nextRxSequence; //next expected sequence
//Rx buffer
UnAckData_t m_bufferedData; //buffer which sorts out of sequence data
//Rx buffer state
uint32_t m_rxAvailable; // amount of data available for reading through Recv
uint32_t m_rxBufSize; //size in bytes of the data in the rx buf
//note that these two are not the same: rxAvailbale is the number of
//contiguous sequenced bytes that can be read, rxBufSize is the TOTAL size
//including out of sequence data, such that m_rxAvailable <= m_rxBufSize
//this is kind of the tx buffer
PendingData* m_pendingData;
SequenceNumber m_firstPendingSequence;
// Window management
uint32_t m_segmentSize; //SegmentSize
uint32_t m_rxWindowSize; //Flow control window
TracedValue<uint32_t> m_cWnd; //Congestion window
uint32_t m_ssThresh; //Slow Start Threshold
uint32_t m_initialCWnd; //Initial cWnd value
//persist timer management
Time m_persistTime;
EventId m_persistEvent;
// Round trip time estimation
Ptr<RttEstimator> m_rtt;
Time m_lastMeasuredRtt;
// Timer-related members
Time m_cnTimeout;
uint32_t m_cnCount;
// Attributes
uint32_t m_sndBufSize; // buffer limit for the outgoing queue
uint32_t m_rxBufMaxSize; // maximum receive socket buffer size
};
}//namespace ns3
#endif /* TCP_SOCKET_IMPL_H */