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tcp-socket-base.h
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1 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
2 /*
3  * Copyright (c) 2007 Georgia Tech Research Corporation
4  * Copyright (c) 2010 Adrian Sai-wah Tam
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation;
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, write to the Free Software
17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18  *
19  * Author: Adrian Sai-wah Tam <adrian.sw.tam@gmail.com>
20  */
21 #ifndef TCP_SOCKET_BASE_H
22 #define TCP_SOCKET_BASE_H
23 
24 #include <stdint.h>
25 #include <queue>
26 #include "ns3/callback.h"
27 #include "ns3/traced-value.h"
28 #include "ns3/tcp-socket.h"
29 #include "ns3/ptr.h"
30 #include "ns3/ipv4-address.h"
31 #include "ns3/ipv4-header.h"
32 #include "ns3/ipv4-interface.h"
33 #include "ns3/ipv6-header.h"
34 #include "ns3/event-id.h"
35 #include "tcp-tx-buffer.h"
36 #include "tcp-rx-buffer.h"
37 #include "rtt-estimator.h"
38 
39 namespace ns3 {
40 
41 class Ipv4EndPoint;
42 class Ipv6EndPoint;
43 class Node;
44 class Packet;
45 class TcpL4Protocol;
46 class TcpHeader;
47 
61 class TcpSocketBase : public TcpSocket
62 {
63 public:
64  static TypeId GetTypeId (void);
68  TcpSocketBase (void);
69 
73  TcpSocketBase (const TcpSocketBase& sock);
74  virtual ~TcpSocketBase (void);
75 
76  // Set associated Node, TcpL4Protocol, RttEstimator to this socket
77  virtual void SetNode (Ptr<Node> node);
78  virtual void SetTcp (Ptr<TcpL4Protocol> tcp);
79  virtual void SetRtt (Ptr<RttEstimator> rtt);
80 
81  // Necessary implementations of null functions from ns3::Socket
82  virtual enum SocketErrno GetErrno (void) const; // returns m_errno
83  virtual enum SocketType GetSocketType (void) const; // returns socket type
84  virtual Ptr<Node> GetNode (void) const; // returns m_node
85  virtual int Bind (void); // Bind a socket by setting up endpoint in TcpL4Protocol
86  virtual int Bind6 (void); // Bind a socket by setting up endpoint in TcpL4Protocol
87  virtual int Bind (const Address &address); // ... endpoint of specific addr or port
88  virtual int Connect (const Address &address); // Setup endpoint and call ProcessAction() to connect
89  virtual int Listen (void); // Verify the socket is in a correct state and call ProcessAction() to listen
90  virtual int Close (void); // Close by app: Kill socket upon tx buffer emptied
91  virtual int ShutdownSend (void); // Assert the m_shutdownSend flag to prevent send to network
92  virtual int ShutdownRecv (void); // Assert the m_shutdownRecv flag to prevent forward to app
93  virtual int Send (Ptr<Packet> p, uint32_t flags); // Call by app to send data to network
94  virtual int SendTo (Ptr<Packet> p, uint32_t flags, const Address &toAddress); // Same as Send(), toAddress is insignificant
95  virtual Ptr<Packet> Recv (uint32_t maxSize, uint32_t flags); // Return a packet to be forwarded to app
96  virtual Ptr<Packet> RecvFrom (uint32_t maxSize, uint32_t flags, Address &fromAddress); // ... and write the remote address at fromAddress
97  virtual uint32_t GetTxAvailable (void) const; // Available Tx buffer size
98  virtual uint32_t GetRxAvailable (void) const; // Available-to-read data size, i.e. value of m_rxAvailable
99  virtual int GetSockName (Address &address) const; // Return local addr:port in address
100  virtual void BindToNetDevice (Ptr<NetDevice> netdevice); // NetDevice with my m_endPoint
101 
102 protected:
103  // Implementing ns3::TcpSocket -- Attribute get/set
104  virtual void SetSndBufSize (uint32_t size);
105  virtual uint32_t GetSndBufSize (void) const;
106  virtual void SetRcvBufSize (uint32_t size);
107  virtual uint32_t GetRcvBufSize (void) const;
108  virtual void SetSegSize (uint32_t size);
109  virtual uint32_t GetSegSize (void) const;
110  virtual void SetSSThresh (uint32_t threshold) = 0;
111  virtual uint32_t GetSSThresh (void) const = 0;
112  virtual void SetInitialCwnd (uint32_t cwnd) = 0;
113  virtual uint32_t GetInitialCwnd (void) const = 0;
114  virtual void SetConnTimeout (Time timeout);
115  virtual Time GetConnTimeout (void) const;
116  virtual void SetConnCount (uint32_t count);
117  virtual uint32_t GetConnCount (void) const;
118  virtual void SetDelAckTimeout (Time timeout);
119  virtual Time GetDelAckTimeout (void) const;
120  virtual void SetDelAckMaxCount (uint32_t count);
121  virtual uint32_t GetDelAckMaxCount (void) const;
122  virtual void SetTcpNoDelay (bool noDelay);
123  virtual bool GetTcpNoDelay (void) const;
124  virtual void SetPersistTimeout (Time timeout);
125  virtual Time GetPersistTimeout (void) const;
126  virtual bool SetAllowBroadcast (bool allowBroadcast);
127  virtual bool GetAllowBroadcast (void) const;
128 
129  // Helper functions: Connection set up
130  int SetupCallback (void); // Common part of the two Bind(), i.e. set callback and remembering local addr:port
131  int DoConnect (void); // Sending a SYN packet to make a connection if the state allows
132  void ConnectionSucceeded (void); // Schedule-friendly wrapper for Socket::NotifyConnectionSucceeded()
133  int SetupEndpoint (void); // Configure m_endpoint for local addr for given remote addr
134  int SetupEndpoint6 (void); // Configure m_endpoint6 for local addr for given remote addr
135  void CompleteFork (Ptr<Packet>, const TcpHeader&, const Address& fromAddress, const Address& toAdress);
136 
137  // Helper functions: Transfer operation
138  void ForwardUp (Ptr<Packet> packet, Ipv4Header header, uint16_t port, Ptr<Ipv4Interface> incomingInterface);
139  void ForwardUp6 (Ptr<Packet> packet, Ipv6Header header, uint16_t port);
140  virtual void DoForwardUp (Ptr<Packet> packet, Ipv4Header header, uint16_t port, Ptr<Ipv4Interface> incomingInterface); //Get a pkt from L3
141  virtual void DoForwardUp (Ptr<Packet> packet, Ipv6Header header, uint16_t port); // Ipv6 version
142  void ForwardIcmp (Ipv4Address icmpSource, uint8_t icmpTtl, uint8_t icmpType, uint8_t icmpCode, uint32_t icmpInfo);
143  void ForwardIcmp6 (Ipv6Address icmpSource, uint8_t icmpTtl, uint8_t icmpType, uint8_t icmpCode, uint32_t icmpInfo);
144  bool SendPendingData (bool withAck = false); // Send as much as the window allows
145  uint32_t SendDataPacket (SequenceNumber32 seq, uint32_t maxSize, bool withAck); // Send a data packet
146  void SendEmptyPacket (uint8_t flags); // Send a empty packet that carries a flag, e.g. ACK
147  void SendRST (void); // Send reset and tear down this socket
148  bool OutOfRange (SequenceNumber32 head, SequenceNumber32 tail) const; // Check if a sequence number range is within the rx window
149 
150  // Helper functions: Connection close
151  int DoClose (void); // Close a socket by sending RST, FIN, or FIN+ACK, depend on the current state
152  void CloseAndNotify (void); // To CLOSED state, notify upper layer, and deallocate end point
153  void Destroy (void); // Kill this socket by zeroing its attributes
154  void Destroy6 (void); // Kill this socket by zeroing its attributes
155  void DeallocateEndPoint (void); // Deallocate m_endPoint
156  void PeerClose (Ptr<Packet>, const TcpHeader&); // Received a FIN from peer, notify rx buffer
157  void DoPeerClose (void); // FIN is in sequence, notify app and respond with a FIN
158  void CancelAllTimers (void); // Cancel all timer when endpoint is deleted
159  void TimeWait (void); // Move from CLOSING or FIN_WAIT_2 to TIME_WAIT state
160 
161  // State transition functions
162  void ProcessEstablished (Ptr<Packet>, const TcpHeader&); // Received a packet upon ESTABLISHED state
163  void ProcessListen (Ptr<Packet>, const TcpHeader&, const Address&, const Address&); // Process the newly received ACK
164  void ProcessSynSent (Ptr<Packet>, const TcpHeader&); // Received a packet upon SYN_SENT
165  void ProcessSynRcvd (Ptr<Packet>, const TcpHeader&, const Address&, const Address&); // Received a packet upon SYN_RCVD
166  void ProcessWait (Ptr<Packet>, const TcpHeader&); // Received a packet upon CLOSE_WAIT, FIN_WAIT_1, FIN_WAIT_2
167  void ProcessClosing (Ptr<Packet>, const TcpHeader&); // Received a packet upon CLOSING
168  void ProcessLastAck (Ptr<Packet>, const TcpHeader&); // Received a packet upon LAST_ACK
169 
170  // Window management
171  virtual uint32_t UnAckDataCount (void); // Return count of number of unacked bytes
172  virtual uint32_t BytesInFlight (void); // Return total bytes in flight
173  virtual uint32_t Window (void); // Return the max possible number of unacked bytes
174  virtual uint32_t AvailableWindow (void); // Return unfilled portion of window
175  virtual uint16_t AdvertisedWindowSize (void); // The amount of Rx window announced to the peer
176 
177  // Manage data tx/rx
178  virtual Ptr<TcpSocketBase> Fork (void) = 0; // Call CopyObject<> to clone me
179  virtual void ReceivedAck (Ptr<Packet>, const TcpHeader&); // Received an ACK packet
180  virtual void ReceivedData (Ptr<Packet>, const TcpHeader&); // Recv of a data, put into buffer, call L7 to get it if necessary
181  virtual void EstimateRtt (const TcpHeader&); // RTT accounting
182  virtual void NewAck (SequenceNumber32 const& seq); // Update buffers w.r.t. ACK
183  virtual void DupAck (const TcpHeader& t, uint32_t count) = 0; // Received dupack
184  virtual void ReTxTimeout (void); // Call Retransmit() upon RTO event
185  virtual void Retransmit (void); // Halving cwnd and call DoRetransmit()
186  virtual void DelAckTimeout (void); // Action upon delay ACK timeout, i.e. send an ACK
187  virtual void LastAckTimeout (void); // Timeout at LAST_ACK, close the connection
188  virtual void PersistTimeout (void); // Send 1 byte probe to get an updated window size
189  virtual void DoRetransmit (void); // Retransmit the oldest packet
190  virtual void ReadOptions (const TcpHeader&); // Read option from incoming packets
191  virtual void AddOptions (TcpHeader&); // Add option to outgoing packets
192 
193 protected:
194  // Counters and events
195  EventId m_retxEvent; //< Retransmission event
196  EventId m_lastAckEvent; //< Last ACK timeout event
197  EventId m_delAckEvent; //< Delayed ACK timeout event
198  EventId m_persistEvent; //< Persist event: Send 1 byte to probe for a non-zero Rx window
199  EventId m_timewaitEvent; //< TIME_WAIT expiration event: Move this socket to CLOSED state
200  uint32_t m_dupAckCount; //< Dupack counter
201  uint32_t m_delAckCount; //< Delayed ACK counter
202  uint32_t m_delAckMaxCount; //< Number of packet to fire an ACK before delay timeout
203  bool m_noDelay; //< Set to true to disable Nagle's algorithm
204  uint32_t m_cnCount; //< Count of remaining connection retries
205  uint32_t m_cnRetries; //< Number of connection retries before giving up
206  TracedValue<Time> m_rto; //< Retransmit timeout
207  TracedValue<Time> m_lastRtt; //< Last RTT sample collected
208  Time m_delAckTimeout; //< Time to delay an ACK
209  Time m_persistTimeout; //< Time between sending 1-byte probes
210  Time m_cnTimeout; //< Timeout for connection retry
211 
212  // Connections to other layers of TCP/IP
213  Ipv4EndPoint* m_endPoint;
214  Ipv6EndPoint* m_endPoint6;
215  Ptr<Node> m_node;
216  Ptr<TcpL4Protocol> m_tcp;
217  Callback<void, Ipv4Address,uint8_t,uint8_t,uint8_t,uint32_t> m_icmpCallback;
218  Callback<void, Ipv6Address,uint8_t,uint8_t,uint8_t,uint32_t> m_icmpCallback6;
219 
220  // Round trip time estimation
221  Ptr<RttEstimator> m_rtt;
222 
223  // Rx and Tx buffer management
224  TracedValue<SequenceNumber32> m_nextTxSequence; //< Next seqnum to be sent (SND.NXT), ReTx pushes it back
225  TracedValue<SequenceNumber32> m_highTxMark; //< Highest seqno ever sent, regardless of ReTx
226  TcpRxBuffer m_rxBuffer; //< Rx buffer (reordering buffer)
227  TcpTxBuffer m_txBuffer; //< Tx buffer
228 
229  // State-related attributes
230  TracedValue<TcpStates_t> m_state; //< TCP state
231  enum SocketErrno m_errno; //< Socket error code
232  bool m_closeNotified; //< Told app to close socket
233  bool m_closeOnEmpty; //< Close socket upon tx buffer emptied
234  bool m_shutdownSend; //< Send no longer allowed
235  bool m_shutdownRecv; //< Receive no longer allowed
236  bool m_connected; //< Connection established
237  double m_msl; //< Max segment lifetime
238 
239  // Window management
240  uint32_t m_segmentSize; //< Segment size
241  uint16_t m_maxWinSize; //< Maximum window size to advertise
242  TracedValue<uint32_t> m_rWnd; //< Flow control window at remote side
243 };
244 
245 } // namespace ns3
246 
247 #endif /* TCP_SOCKET_BASE_H */