/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */ /* * Copyright (c) 2005,2006 INRIA * All rights reserved. * * 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: Mathieu Lacage * Modified by Emmanuelle Laprise to remove dependance on LLC headers */ #ifndef NET_DEVICE_H #define NET_DEVICE_H #include #include #include "ns3/callback.h" #include "ns3/packet.h" #include "ns3/object.h" #include "ns3/ptr.h" #include "address.h" #include "ipv4-address.h" namespace ns3 { class Node; class TraceResolver; class TraceContext; class Channel; /** * \brief Network layer to device interface * * This interface defines the API which the IP and ARP * layers need to access to manage an instance of a network device * layer. It currently does not support MAC-level * multicast but this should not be too hard to add by adding * extra methods to register MAC multicast addresses to * filter out unwanted packets before handing them to the * higher layers. * * In Linux, this interface is analogous to the interface * just above dev_queue_xmit() (i.e., IP packet is fully * constructed with destination MAC address already selected). * * If you want to write a new MAC layer, you need to subclass * this base class and implement your own version of the * NetDevice::SendTo method. */ class NetDevice : public Object { public: static const InterfaceId iid; virtual ~NetDevice(); /** * \param context the trace context to use to construct the * TraceResolver to return * \returns a TraceResolver which can resolve all traces * performed in this object. The caller must * delete the returned object. */ TraceResolver *CreateTraceResolver (TraceContext const &context); /** * \return the channel this NetDevice is connected to. The value * returned can be zero if the NetDevice is not yet connected * to any channel. */ Ptr GetChannel (void) const; /** * \return the current Address of this interface. */ Address GetAddress (void) const; /** * \param mtu MTU value, in bytes, to set for the device * \return whether the MTU value was within legal bounds * * Override for default MTU defined on a per-type basis. */ bool SetMtu (const uint16_t mtu); /** * \return the link-level MTU in bytes for this interface. * * This value is typically used by the IP layer to perform * IP fragmentation when needed. */ uint16_t GetMtu (void) const; /** * \param name name of the device (e.g. "eth0") */ void SetName(const std::string name); /** * \return name name of the device (e.g. "eth0") */ std::string GetName(void) const; /** * \param index ifIndex of the device */ void SetIfIndex(const uint32_t index); /** * \return index ifIndex of the device */ uint32_t GetIfIndex(void) const; /** * \return true if link is up; false otherwise */ bool IsLinkUp (void) const; /** * \param callback the callback to invoke * * Register a callback invoked whenever the link * status changes to UP. This callback is typically used * by the IP/ARP layer to flush the ARP cache * whenever the link goes up. */ void SetLinkChangeCallback (Callback callback); /** * \return true if this interface supports a broadcast address, * false otherwise. */ bool IsBroadcast (void) const; /** * \return the broadcast address supported by * this netdevice. * * Calling this method is invalid if IsBroadcast returns * not true. */ Address const &GetBroadcast (void) const; /** * \return value of m_isMulticast flag */ bool IsMulticast (void) const; /** * \brief Return the MAC multicast base address used when mapping multicast * groups to MAC multicast addresses. * * Typically when one constructs a multicast MAC addresses, some bits from * the IP multicast group are copied into a corresponding MAC multicast * group. In EUI-48, for example, the low order 23 bits of the multicast * group are copied to the MAC multicast group base address. * * This method allows access to the underlying MAC multicast group base * address. It is expected that in most cases, a net device client will * allow the net device to perform the actual construction of the multicast * address. Use of this method is discouraged unless you have a good reason * to perform a custom mapping. You should prefer * NetDevice::MakeMulticastAddress which will do the RFC-specified mapping * for the net device in question. * * \return The multicast address supported by this net device. * * \warning Calling this method is invalid if IsMulticast returns not true. * The method NS_ASSERTs if the device is not a multicast device. * \see NetDevice::MakeMulticastAddress */ Address GetMulticast (void) const; /** * \brief Make and return a MAC multicast address using the provided * multicast group * * RFC 1112 says that an Ipv4 host group address is mapped to an Ethernet * multicast address by placing the low-order 23-bits of the IP address into * the low-order 23 bits of the Ethernet multicast address * 01-00-5E-00-00-00 (hex). Similar RFCs exist for Ipv6 and Eui64 mappings. * This method performs the multicast address creation function appropriate * to the underlying MAC address of the device. This MAC address is * encapsulated in an abstract Address to avoid dependencies on the exact * MAC address format. * * A default imlementation of MakeMulticastAddress is provided, but this * method simply NS_ASSERTS. In the case of net devices that do not support * multicast, clients are expected to test NetDevice::IsMulticast and avoid * attempting to map multicast packets. Subclasses of NetDevice that do * support multicasting are expected to override this method and provide an * implementation appropriate to the particular device. * * \param multicastGroup The IP address for the multicast group destination * of the packet. * \return The MAC multicast Address used to send packets to the provided * multicast group. * * \warning Calling this method is invalid if IsMulticast returns not true. * \see Ipv4Address * \see Address * \see NetDevice::IsMulticast */ virtual Address MakeMulticastAddress (Ipv4Address multicastGroup) const; /** * \return value of m_isPointToPoint flag */ bool IsPointToPoint (void) const; /** * \param p packet sent from above down to Network Device * \param dest mac address of the destination (already resolved) * \param protocolNumber identifies the type of payload contained in * this packet. Used to call the right L3Protocol when the packet * is received. * * Called from higher layer to send packet into Network Device * to the specified destination Address * * \return whether the Send operation succeeded */ bool Send(const Packet& p, const Address& dest, uint16_t protocolNumber); /** * \returns the node base class which contains this network * interface. * * When a subclass needs to get access to the underlying node * base class to print the nodeid for example, it can invoke * this method. */ Ptr GetNode (void) const; /** * \returns true if ARP is needed, false otherwise. * * Called by higher-layers to check if this NetDevice requires * ARP to be used. */ bool NeedsArp (void) const; /** * \param device a pointer to the net device which is calling this callback * \param packet the packet received * \param protocol the 16 bit protocol number associated with this packet. * This protocol number is expected to be the same protocol number * given to the Send method by the user on the sender side. * \param address the address of the sender * \returns true if the callback could handle the packet successfully, false * otherwise. */ typedef Callback,const Packet &,uint16_t,const Address &> ReceiveCallback; /** * \param cb callback to invoke whenever a packet has been received and must * be forwarded to the higher layers. * */ void SetReceiveCallback (ReceiveCallback cb); protected: /** * \param node base class node pointer of device's node * \param addr MAC address of this device. */ NetDevice(Ptr node, const Address& addr); /** * Enable broadcast support. This method should be * called by subclasses from their constructor */ void EnableBroadcast (Address broadcast); /** * Set m_isBroadcast flag to false */ void DisableBroadcast (void); /** * Enable multicast support. This method should be * called by subclasses from their constructor */ void EnableMulticast (Address multicast); /** * Set m_isMulticast flag to false */ void DisableMulticast (void); /** * Set m_isPointToPoint flag to true */ void EnablePointToPoint (void); /** * Set m_isPointToPoint flag to false */ void DisablePointToPoint (void); /** * When a subclass notices that the link status has changed to up, * it notifies its parent class by calling this method. This method * is responsible for notifying any LinkUp callbacks. */ void NotifyLinkUp (void); /** * When a subclass notices that the link status has changed to * down, it notifies its parent class by calling this method. */ void NotifyLinkDown (void); /** * \param p packet sent from below up to Network Device * \param param Extra parameter extracted from header and needed by * some protocols * \param address the address of the sender of this packet. * \returns true if the packet was forwarded successfully, * false otherwise. * * When a subclass gets a packet from the channel, it * forwards it to the higher layers by calling this method * which is responsible for passing it up to the Rx callback. */ bool ForwardUp (const Packet& p, uint16_t param, const Address &address); /** * The dispose method for this NetDevice class. * Subclasses are expected to override this method _and_ * to chain up to it by calling NetDevice::DoDispose * at the end of their own DoDispose method. */ virtual void DoDispose (void); private: /** * \param p packet to send * \param dest address of destination to which packet must be sent * \param protocolNumber Number of the protocol (used with some protocols) * \returns true if the packet could be sent successfully, false * otherwise. * * This is the private virtual target function of the public Send() * method. When the link is Up, this method is invoked to ask * subclasses to forward packets. Subclasses MUST override this method. */ virtual bool SendTo (const Packet& p, const Address &dest, uint16_t protocolNumber) = 0; /** * \returns true if this NetDevice needs the higher-layers * to perform ARP over it, false otherwise. * * Subclasses must implement this method. */ virtual bool DoNeedsArp (void) const = 0; /** * \param context the trace context to associated to the * trace resolver. * \returns a trace resolver associated to the input context. * the caller takes ownership of the pointer returned. * * Subclasses must implement this method. */ virtual TraceResolver *DoCreateTraceResolver (TraceContext const &context) = 0; /** * \returns the channel associated to this NetDevice. * * Subclasses must implement this method. */ virtual Ptr DoGetChannel (void) const = 0; Ptr m_node; std::string m_name; uint16_t m_ifIndex; Address m_address; Address m_broadcast; Address m_multicast; uint16_t m_mtu; bool m_isUp; bool m_isBroadcast; bool m_isMulticast; bool m_isPointToPoint; Callback m_linkChangeCallback; ReceiveCallback m_receiveCallback; }; }; // namespace ns3 #endif