/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
/*
* Copyright (c) 2006 Georgia Tech Research Corporation
* 2007 INRIA
*
* 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
*
* Authors: George F. Riley<riley@ece.gatech.edu>
* Mathieu Lacage <mathieu.lacage@sophia.inria.fr>
*/
#ifndef __SOCKET_H__
#define __SOCKET_H__
#include "ns3/callback.h"
#include "ns3/ptr.h"
#include "ns3/tag.h"
#include "ns3/object.h"
#include "address.h"
#include <stdint.h>
namespace ns3 {
class Node;
class Packet;
/**
* \ingroup node
* \defgroup socket Socket
*/
/**
* \brief A low-level Socket API based loosely on the BSD Socket API.
* \ingroup socket
*
* A few things to keep in mind about this type of socket:
* - it uses ns-3 API constructs such as class ns3::Address instead of
* C-style structs
* - in contrast to the original BSD socket API, this API is asynchronous:
* it does not contain blocking calls. Sending and receiving operations
* must make use of the callbacks provided.
* - It also uses class ns3::Packet as a fancy byte buffer, allowing
* data to be passed across the API using an ns-3 Packet instead of
* a raw data pointer.
* - Not all of the full POSIX sockets API is supported
*
* Other than that, it tries to stick to the BSD API to make it
* easier for those who know the BSD API to use this API.
* More details are provided in the ns-3 tutorial.
*/
class Socket : public Object
{
public:
Socket (void);
virtual ~Socket (void);
enum SocketErrno {
ERROR_NOTERROR,
ERROR_ISCONN,
ERROR_NOTCONN,
ERROR_MSGSIZE,
ERROR_AGAIN,
ERROR_SHUTDOWN,
ERROR_OPNOTSUPP,
ERROR_AFNOSUPPORT,
ERROR_INVAL,
ERROR_BADF,
ERROR_NOROUTETOHOST,
SOCKET_ERRNO_LAST
};
/**
* This method wraps the creation of sockets that is performed
* by a socket factory on a given node based on a TypeId.
*
* \return A smart pointer to a newly created socket.
*
* \param node The node on which to create the socket
* \param tid The TypeId of the socket to create
*/
static Ptr<Socket> CreateSocket (Ptr<Node> node, TypeId tid);
/**
* \return the errno associated to the last call which failed in this
* socket. Each socket's errno is initialized to zero
* when the socket is created.
*/
virtual enum Socket::SocketErrno GetErrno (void) const = 0;
/**
* \returns the node this socket is associated with.
*/
virtual Ptr<Node> GetNode (void) const = 0;
/**
* \param connectionSucceeded this callback is invoked when the
* connection request initiated by the user is successfully
* completed. The callback is passed back a pointer to
* the same socket object.
* \param connectionFailed this callback is invoked when the
* connection request initiated by the user is unsuccessfully
* completed. The callback is passed back a pointer to the
* same socket object.
*/
void SetConnectCallback (Callback<void, Ptr<Socket> > connectionSucceeded,
Callback<void, Ptr<Socket> > connectionFailed);
/**
* \brief Accept connection requests from remote hosts
* \param connectionRequest Callback for connection request from peer.
* This user callback is passed a pointer to this socket, the
* ip address and the port number of the connection originator.
* This callback must return true to accept the incoming connection,
* false otherwise. If the connection is accepted, the
* "newConnectionCreated" callback will be invoked later to
* give access to the user to the socket created to match
* this new connection. If the user does not explicitly
* specify this callback, all incoming connections will be refused.
* \param newConnectionCreated Callback for new connection: when a new
* is accepted, it is created and the corresponding socket is passed
* back to the user through this callback. This user callback is
* passed a pointer to the new socket, and the ip address and
* port number of the connection originator.
*/
void SetAcceptCallback (Callback<bool, Ptr<Socket>,
const Address &> connectionRequest,
Callback<void, Ptr<Socket>,
const Address&> newConnectionCreated);
/**
* \brief Notify application when a packet has been sent from transport
* protocol (non-standard socket call)
* \param dataSent Callback for the event that data is sent from the
* underlying transport protocol. This callback is passed a
* pointer to the socket, and the number of bytes sent.
*/
void SetDataSentCallback (Callback<void, Ptr<Socket>,
uint32_t> dataSent);
/**
* \brief Notify application when space in transmit buffer is added
*
* This callback is intended to notify a
* socket that would have been blocked in a blocking socket model
* that space is available in the transmit buffer and that it
* can call Send() again.
*
* \param sendCb Callback for the event that the socket transmit buffer
* fill level has decreased. This callback is passed a pointer to
* the socket, and the number of bytes available for writing
* into the buffer (an absolute value). If there is no transmit
* buffer limit, a maximum-sized integer is always returned.
*/
void SetSendCallback (Callback<void, Ptr<Socket>, uint32_t> sendCb);
/**
* \brief Notify application when new data is available to be read.
*
* This callback is intended to notify a socket that would
* have been blocked in a blocking socket model that data
* is available to be read.
*/
void SetRecvCallback (Callback<void, Ptr<Socket> >);
/**
* \param address the address to try to allocate
* \returns 0 on success, -1 on failure.
*
* Allocate a local endpoint for this socket.
*/
virtual int Bind (const Address &address) = 0;
/**
* Allocate a local endpoint for this socket.
*
* \returns 0 on success, -1 on failure.
*/
virtual int Bind () = 0;
/**
* \brief Close a socket.
*
* After the Close call, the socket is no longer valid, and cannot
* safely be used for subsequent operations.
*/
virtual int Close (void) = 0;
/**
* \returns zero on success, -1 on failure.
*
* Do not allow any further Send calls. This method is typically
* implemented for Tcp sockets by a half close.
*/
virtual int ShutdownSend (void) = 0;
/**
* \returns zero on success, -1 on failure.
*
* Do not allow any further Recv calls. This method is typically
* implemented for Tcp sockets by a half close.
*/
virtual int ShutdownRecv (void) = 0;
/**
* \brief Initiate a connection to a remote host
* \param address Address of remote.
*/
virtual int Connect (const Address &address) = 0;
/**
* \brief Listen for incoming connections.
* \param queueLimit maximum number of incoming request to queue
* \returns 0 on success, -1 on error (in which case errno is set).
*/
virtual int Listen (void) = 0;
/**
* \brief Returns the number of bytes which can be sent in a single call
* to Send.
*
* For datagram sockets, this returns the number of bytes that
* can be passed atomically through the underlying protocol.
*
* For stream sockets, this returns the available space in bytes
* left in the transmit buffer.
*/
virtual uint32_t GetTxAvailable (void) const = 0;
/**
* \brief Send data (or dummy data) to the remote host
*
* This function matches closely in semantics to the send() function
* call in the standard C library (libc):
* ssize_t send (int s, const void *msg, size_t len, int flags);
* except that the send I/O is asynchronous. This is the
* primary Send method at this low-level API and must be implemented
* by subclasses.
*
* In a typical blocking sockets model, this call would block upon
* lack of space to hold the message to be sent. In ns-3 at this
* API, the call returns immediately in such a case, but the callback
* registered with SetSendCallback() is invoked when the socket
* has space (when it conceptually unblocks); this is an asynchronous
* I/O model for send().
*
* This variant of Send() uses class ns3::Packet to encapsulate
* data, rather than providing a raw pointer and length field.
* This allows an ns-3 application to attach tags if desired (such
* as a flow ID) and may allow the simulator to avoid some data
* copies. Despite the appearance of sending Packets on a stream
* socket, just think of it as a fancy byte buffer with streaming
* semantics.
*
* If either the message buffer within the Packet is too long to pass
* atomically through the underlying protocol (for datagram sockets),
* or the message buffer cannot entirely fit in the transmit buffer
* (for stream sockets), -1 is returned and SocketErrno is set
* to ERROR_MSGSIZE. If the packet does not fit, the caller can
* split the Packet (based on information obtained from
* GetTxAvailable) and reattempt to send the data.
*
* The flags argument is formed by or'ing one or more of the values:
* MSG_OOB process out-of-band data
* MSG_DONTROUTE bypass routing, use direct interface
* These flags are _unsupported_ as of ns-3.1.
*
* \param p ns3::Packet to send
* \param flags Socket control flags
* \returns the number of bytes accepted for transmission if no error
* occurs, and -1 otherwise.
*
* \see SetSendCallback
*/
virtual int Send (Ptr<Packet> p, uint32_t flags) = 0;
/**
* \brief Send data to a specified peer.
*
* This method has similar semantics to Send () but subclasses may
* want to provide checks on socket state, so the implementation is
* pushed to subclasses.
*
* \param p packet to send
* \param flags Socket control flags
* \param toAddress IP Address of remote host
* \returns -1 in case of error or the number of bytes copied in the
* internal buffer and accepted for transmission.
*/
virtual int SendTo (Ptr<Packet> p, uint32_t flags,
const Address &toAddress) = 0;
/**
* Return number of bytes which can be returned from one or
* multiple calls to Recv.
* Must be possible to call this method from the Recv callback.
*/
virtual uint32_t GetRxAvailable (void) const = 0;
/**
* \brief Read data from the socket
*
* This function matches closely in semantics to the recv() function
* call in the standard C library (libc):
* ssize_t recv (int s, void *buf, size_t len, int flags);
* except that the receive I/O is asynchronous. This is the
* primary Recv method at this low-level API and must be implemented
* by subclasses.
*
* This method is normally used only on a connected socket.
* In a typical blocking sockets model, this call would block until
* at least one byte is returned or the connection closes.
* In ns-3 at this API, the call returns immediately in such a case
* and returns 0 if nothing is available to be read.
* However, an application can set a callback, ns3::SetRecvCallback,
* to be notified of data being available to be read
* (when it conceptually unblocks); this is an asynchronous
* I/O model for recv().
*
* This variant of Recv() uses class ns3::Packet to encapsulate
* data, rather than providing a raw pointer and length field.
* This allows an ns-3 application to attach tags if desired (such
* as a flow ID) and may allow the simulator to avoid some data
* copies. Despite the appearance of receiving Packets on a stream
* socket, just think of it as a fancy byte buffer with streaming
* semantics.
*
* The semantics depend on the type of socket. For a datagram socket,
* each Recv() returns the data from at most one Send(), and order
* is not necessarily preserved. For a stream socket, the bytes
* are delivered in order, and on-the-wire packet boundaries are
* not preserved.
*
* The flags argument is formed by or'ing one or more of the values:
* MSG_OOB process out-of-band data
* MSG_PEEK peek at incoming message
* None of these flags are supported for now.
*
* Some variants of Recv() are supported as additional API,
* including RecvFrom(), overloaded Recv() without arguments,
* and variants that use raw character buffers.
*
* \param maxSize reader will accept packet up to maxSize
* \param flags Socket control flags
* \returns Ptr<Packet> of the next in-sequence packet. Returns
* 0 if the socket cannot return a next in-sequence packet conforming
* to the maxSize and flags.
*
* \see SetRecvCallback
*/
virtual Ptr<Packet> Recv (uint32_t maxSize, uint32_t flags) = 0;
/**
* \brief Read a single packet from the socket and retrieve the sender
* address.
*
* Calls Recv(maxSize, flags) with maxSize
* implicitly set to maximum sized integer, and flags set to zero.
*
* This method has similar semantics to Recv () but subclasses may
* want to provide checks on socket state, so the implementation is
* pushed to subclasses.
*
* \param maxSize reader will accept packet up to maxSize
* \param flags Socket control flags
* \param fromAddress output parameter that will return the
* address of the sender of the received packet, if any. Remains
* untouched if no packet is received.
* \returns Ptr<Packet> of the next in-sequence packet. Returns
* 0 if the socket cannot return a next in-sequence packet.
*/
virtual Ptr<Packet> RecvFrom (uint32_t maxSize, uint32_t flags,
Address &fromAddress) = 0;
/////////////////////////////////////////////////////////////////////
// The remainder of these public methods are overloaded methods //
// or variants of Send() and Recv(), and they are non-virtual //
/////////////////////////////////////////////////////////////////////
/**
* \brief Send data (or dummy data) to the remote host
*
* Overloaded version of Send(..., flags) with flags set to zero.
*
* \param p ns3::Packet to send
* \returns the number of bytes accepted for transmission if no error
* occurs, and -1 otherwise.
*/
int Send (Ptr<Packet> p);
/**
* \brief Send data (or dummy data) to the remote host
*
* This method is provided so as to have an API which is closer in
* appearance to that of real network or BSD sockets.
*
* \param buf A pointer to a raw byte buffer of some data to send. If
* this buffer is 0, we send dummy data whose size is specified by the
* second parameter
* \param size the number of bytes to copy from the buffer
* \param flags Socket control flags
*/
int Send (const uint8_t* buf, uint32_t size, uint32_t flags);
/**
* \brief Send data to a specified peer.
*
* This method is provided so as to have an API which is closer in
* appearance to that of real network or BSD sockets.
*
* \param buf A pointer to a raw byte buffer of some data to send.
* If this is 0, we send dummy data whose size is specified by the
* third parameter
* \param size the number of bytes to copy from the buffer
* \param flags Socket control flags
* \param address IP Address of remote host
* \returns -1 in case of error or the number of bytes copied in the
* internal buffer and accepted for transmission.
*
*/
int SendTo (const uint8_t* buf, uint32_t size, uint32_t flags,
const Address &address);
/**
* \brief Read a single packet from the socket
*
* Overloaded version of Recv(maxSize, flags) with maxSize
* implicitly set to maximum sized integer, and flags set to zero.
*
* \returns Ptr<Packet> of the next in-sequence packet. Returns
* 0 if the socket cannot return a next in-sequence packet.
*/
Ptr<Packet> Recv (void);
/**
* \brief Recv data (or dummy data) from the remote host
*
* This method is provided so as to have an API which is closer in
* appearance to that of real network or BSD sockets.
*
* If the underlying packet was carring null (fake) data, this buffer
* will be zeroed up to the length specified by the return value.
*
* \param buf A pointer to a raw byte buffer to write the data to.
* \param size Number of bytes (at most) to copy to buf
* \param flags any flags to pass to the socket
* \returns number of bytes copied into buf
*/
int Recv (uint8_t* buf, uint32_t size, uint32_t flags);
/**
* \brief Read a single packet from the socket and retrieve the sender
* address.
*
* Calls RecvFrom (maxSize, flags, fromAddress) with maxSize
* implicitly set to maximum sized integer, and flags set to zero.
*
* \param fromAddress output parameter that will return the
* address of the sender of the received packet, if any. Remains
* untouched if no packet is received.
* \returns Ptr<Packet> of the next in-sequence packet. Returns
* 0 if the socket cannot return a next in-sequence packet.
*/
Ptr<Packet> RecvFrom (Address &fromAddress);
/**
* \brief Read a single packet from the socket and retrieve the sender
* address.
*
* This method is provided so as to have an API which is closer in
* appearance to that of real network or BSD sockets.
*
* \param buf A pointer to a raw byte buffer to write the data to.
* If the underlying packet was carring null (fake) data, this buffer
* will be zeroed up to the length specified by the return value.
* \param size Number of bytes (at most) to copy to buf
* \param flags any flags to pass to the socket
* \param fromAddress output parameter that will return the
* address of the sender of the received packet, if any. Remains
* untouched if no packet is received.
* \returns number of bytes copied into buf
*/
int RecvFrom (uint8_t* buf, uint32_t size, uint32_t flags,
Address &fromAddress);
/**
* \returns the address name this socket is associated with.
*/
virtual int GetSockName (Address &address) const = 0;
protected:
void NotifyConnectionSucceeded (void);
void NotifyConnectionFailed (void);
bool NotifyConnectionRequest (const Address &from);
void NotifyNewConnectionCreated (Ptr<Socket> socket, const Address &from);
void NotifyDataSent (uint32_t size);
void NotifySend (uint32_t spaceAvailable);
void NotifyDataRecv (void);
private:
Callback<void, Ptr<Socket> > m_connectionSucceeded;
Callback<void, Ptr<Socket> > m_connectionFailed;
Callback<bool, Ptr<Socket>, const Address &> m_connectionRequest;
Callback<void, Ptr<Socket>, const Address&> m_newConnectionCreated;
Callback<void, Ptr<Socket>, uint32_t> m_dataSent;
Callback<void, Ptr<Socket>, uint32_t > m_sendCb;
Callback<void, Ptr<Socket> > m_receivedData;
};
/**
* \brief This class implements a tag that carries an address
* of a packet across the socket interface.
*/
class SocketAddressTag : public Tag
{
public:
SocketAddressTag ();
void SetAddress (Address addr);
Address GetAddress (void) const;
static TypeId GetTypeId (void);
virtual TypeId GetInstanceTypeId (void) const;
virtual uint32_t GetSerializedSize (void) const;
virtual void Serialize (TagBuffer i) const;
virtual void Deserialize (TagBuffer i);
virtual void Print (std::ostream &os) const;
private:
Address m_address;
};
/**
* \brief This class implements a tag that carries the socket-specific
* TTL of a packet to the IP layer
*/
class SocketIpTtlTag : public Tag
{
public:
SocketIpTtlTag ();
void SetTtl (uint8_t ttl);
uint8_t GetTtl (void) const;
static TypeId GetTypeId (void);
virtual TypeId GetInstanceTypeId (void) const;
virtual uint32_t GetSerializedSize (void) const;
virtual void Serialize (TagBuffer i) const;
virtual void Deserialize (TagBuffer i);
virtual void Print (std::ostream &os) const;
private:
uint8_t m_ttl;
};
/**
* \brief indicated whether packets should be sent out with
* the DF flag set.
*/
class SocketSetDontFragmentTag : public Tag
{
public:
SocketSetDontFragmentTag ();
void Enable (void);
void Disable (void);
bool IsEnabled (void) const;
static TypeId GetTypeId (void);
virtual TypeId GetInstanceTypeId (void) const;
virtual uint32_t GetSerializedSize (void) const;
virtual void Serialize (TagBuffer i) const;
virtual void Deserialize (TagBuffer i);
virtual void Print (std::ostream &os) const;
private:
bool m_dontFragment;
};
} //namespace ns3
#endif /* SOCKET_H */