A bridge to make it appear that a real host process is connected to an ns-3 net device. More...

#include <tap-bridge.h>

Inheritance diagram for ns3::TapBridge:

Collaboration diagram for ns3::TapBridge:

Public Types
enum	Mode { ILLEGAL, CONFIGURE_LOCAL, USE_LOCAL, USE_BRIDGE }
	Enumeration of the operating modes supported in the class. More...

Public Types inherited from ns3::NetDevice
enum	PacketType { PACKET_HOST = 1, NS3_PACKET_HOST = PACKET_HOST, PACKET_BROADCAST, NS3_PACKET_BROADCAST = PACKET_BROADCAST, PACKET_MULTICAST, NS3_PACKET_MULTICAST = PACKET_MULTICAST, PACKET_OTHERHOST, NS3_PACKET_OTHERHOST = PACKET_OTHERHOST }
	Packet types are used as they are in Linux. More...

typedef Callback< bool, Ptr < NetDevice >, Ptr< const Packet >, uint16_t, const Address &, const Address &, enum PacketType >	PromiscReceiveCallback

typedef Callback< bool, Ptr < NetDevice >, Ptr< const Packet >, uint16_t, const Address & >	ReceiveCallback

Public Member Functions
	TapBridge ()

virtual	~TapBridge ()

virtual void	AddLinkChangeCallback (Callback< void > callback)

virtual Address	GetAddress (void) const

Ptr< NetDevice >	GetBridgedNetDevice (void)
	Get the bridged net device. More...

virtual Address	GetBroadcast (void) const

virtual Ptr< Channel >	GetChannel (void) const

virtual uint32_t	GetIfIndex (void) const

TapBridge::Mode	GetMode (void)
	Get the operating mode of this device. More...

virtual uint16_t	GetMtu (void) const

virtual Address	GetMulticast (Ipv4Address multicastGroup) const
	Make and return a MAC multicast address using the provided multicast group. More...

virtual Address	GetMulticast (Ipv6Address addr) const
	Get the MAC multicast address corresponding to the IPv6 address provided. More...

virtual Ptr< Node >	GetNode (void) const

virtual bool	IsBridge (void) const
	Return true if the net device is acting as a bridge. More...

virtual bool	IsBroadcast (void) const

virtual bool	IsLinkUp (void) const

virtual bool	IsMulticast (void) const

virtual bool	IsPointToPoint (void) const
	Return true if the net device is on a point-to-point link. More...

virtual bool	NeedsArp (void) const

virtual bool	Send (Ptr< Packet > packet, const Address &dest, uint16_t protocolNumber)

virtual bool	SendFrom (Ptr< Packet > packet, const Address &source, const Address &dest, uint16_t protocolNumber)

virtual void	SetAddress (Address address)
	Set the address of this interface. More...

void	SetBridgedNetDevice (Ptr< NetDevice > bridgedDevice)
	Set the ns-3 net device to bridge. More...

virtual void	SetIfIndex (const uint32_t index)

void	SetMode (TapBridge::Mode mode)
	Set the operating mode of this device. More...

virtual bool	SetMtu (const uint16_t mtu)

virtual void	SetNode (Ptr< Node > node)

virtual void	SetPromiscReceiveCallback (NetDevice::PromiscReceiveCallback cb)

virtual void	SetReceiveCallback (NetDevice::ReceiveCallback cb)

void	Start (Time tStart)
	Set a start time for the device. More...

void	Stop (Time tStop)
	Set a stop time for the device. More...

virtual bool	SupportsSendFrom () const

Public Member Functions inherited from ns3::NetDevice
virtual	~NetDevice ()

Public Member Functions inherited from ns3::Object
	Object ()

virtual	~Object ()

void	AggregateObject (Ptr< Object > other)

void	Dispose (void)
	Run the DoDispose methods of this object and all the objects aggregated to it. More...

AggregateIterator	GetAggregateIterator (void) const

virtual TypeId	GetInstanceTypeId (void) const

template<typename T >
Ptr< T >	GetObject (void) const

template<typename T >
Ptr< T >	GetObject (TypeId tid) const

void	Initialize (void)
	This method calls the virtual DoInitialize method on all the objects aggregated to this object. More...

Public Member Functions inherited from ns3::SimpleRefCount< Object, ObjectBase, ObjectDeleter >
	SimpleRefCount ()
	Constructor. More...

	SimpleRefCount (const SimpleRefCount &o)
	Copy constructor. More...

uint32_t	GetReferenceCount (void) const
	Get the reference count of the object. More...

SimpleRefCount &	operator= (const SimpleRefCount &o)
	Assignment. More...

void	Ref (void) const
	Increment the reference count. More...

void	Unref (void) const
	Decrement the reference count. More...

Public Member Functions inherited from ns3::ObjectBase
virtual	~ObjectBase ()
	Virtual destructor. More...

void	GetAttribute (std::string name, AttributeValue &value) const

bool	GetAttributeFailSafe (std::string name, AttributeValue &attribute) const

void	SetAttribute (std::string name, const AttributeValue &value)

bool	SetAttributeFailSafe (std::string name, const AttributeValue &value)

bool	TraceConnect (std::string name, std::string context, const CallbackBase &cb)

bool	TraceConnectWithoutContext (std::string name, const CallbackBase &cb)

bool	TraceDisconnect (std::string name, std::string context, const CallbackBase &cb)

bool	TraceDisconnectWithoutContext (std::string name, const CallbackBase &cb)

Static Public Member Functions
static TypeId	GetTypeId (void)

Static Public Member Functions inherited from ns3::NetDevice
static TypeId	GetTypeId (void)

Static Public Member Functions inherited from ns3::Object
static TypeId	GetTypeId (void)
	Register this type. More...

Static Public Member Functions inherited from ns3::SimpleRefCount< Object, ObjectBase, ObjectDeleter >
static void	Cleanup (void)
	Noop. More...

Static Public Member Functions inherited from ns3::ObjectBase
static TypeId	GetTypeId (void)
	Get the type ID. More...

Protected Member Functions
bool	DiscardFromBridgedDevice (Ptr< NetDevice > device, Ptr< const Packet > packet, uint16_t protocol, Address const &src)

virtual void	DoDispose (void)

bool	ReceiveFromBridgedDevice (Ptr< NetDevice > device, Ptr< const Packet > packet, uint16_t protocol, Address const &src, Address const &dst, PacketType packetType)

Protected Member Functions inherited from ns3::Object
	Object (const Object &o)

virtual void	DoInitialize (void)
	This method is called only once by Object::Initialize. More...

virtual void	NotifyNewAggregate (void)
	This method is invoked whenever two sets of objects are aggregated together. More...

Protected Member Functions inherited from ns3::ObjectBase
void	ConstructSelf (const AttributeConstructionList &attributes)

virtual void	NotifyConstructionCompleted (void)
	This method is invoked once all member attributes have been initialized. More...

Private Member Functions
void	CreateTap (void)

Ptr< Packet >	Filter (Ptr< Packet > packet, Address src, Address dst, uint16_t *type)

void	ForwardToBridgedDevice (uint8_t *buf, ssize_t len)

void	NotifyLinkUp (void)

void	ReadCallback (uint8_t *buf, ssize_t len)

void	StartTapDevice (void)

void	StopTapDevice (void)

Private Attributes
Mac48Address	m_address

Ptr< NetDevice >	m_bridgedDevice

Ptr< TapBridgeFdReader >	m_fdReader

uint32_t	m_ifIndex

TracedCallback	m_linkChangeCallbacks

bool	m_linkUp

Mode	m_mode

uint16_t	m_mtu

Ptr< Node >	m_node

uint32_t	m_nodeId

bool	m_ns3AddressRewritten

uint8_t *	m_packetBuffer
	A 64K buffer to hold packet data while it is being sent. More...

NetDevice::PromiscReceiveCallback	m_promiscRxCallback

NetDevice::ReceiveCallback	m_rxCallback

int	m_sock

EventId	m_startEvent

EventId	m_stopEvent

std::string	m_tapDeviceName

Ipv4Address	m_tapGateway

Ipv4Address	m_tapIp

Mac48Address	m_tapMac

Ipv4Mask	m_tapNetmask

Time	m_tStart

Time	m_tStop

Detailed Description

A bridge to make it appear that a real host process is connected to an ns-3 net device.

The Tap Bridge lives in a kind of a gray world somewhere between a Linux host and an ns-3 bridge device. From the Linux perspective, this code appears as the user mode handler for a Tap net device. That is, when the Linux host writes to a /dev/tap device (that is either manually or automatically created depending on basic operating mode – more on this later), the write is redirected into the TapBridge that lives in the ns-3 world; and from this perspective, becomes a read. In other words, a Linux process writes a packet to a tap device and this packet is redirected to an ns-3 process where it is received by the TapBridge as a result of a read operation there. The TapBridge then sends the packet to the ns-3 net device to which it is bridged. In the other direction, a packet received by an ns-3 net device is bridged to the TapBridge (it appears via a callback from that net device. The TapBridge then takes that packet and writes it back to the host using the Linux TAP mechanism. This write to the device will then appear to the Linux host as if a packet has arrived on its device.

The upshot is that the Tap Bridge appears to bridge a tap device on a Linux host in the "real world" to an ns-3 net device in the simulation and make is appear that a ns-3 net device is actually installed in the Linux host. In order to do this on the ns-3 side, we need a "ghost node" in the simulation to hold the bridged ns-3 net device and the TapBridge. This node should not actually do anything else in the simulation since its job is simply to make the net device appear in Linux. This is not just arbitrary policy, it is because:

Bits sent to the Tap Bridge from higher layers in the ghost node (using the TapBridge Send() method) are completely ignored. The Tap Bridge is not, itself, connected to any network, neither in Linux nor in ns-3;
The bridged ns-3 net device is has had its receive callback disconnected from the ns-3 node and reconnected to the Tap Bridge. All data received by a bridged device will be sent to the Linux host and will not be received by the node. From the perspective of the ghost node, you can send over this device but you cannot ever receive.

Of course, if you understand all of the issues you can take control of your own destiny and do whatever you want – we do not actively prevent you from using the ghost node for anything you decide. You will be able to perform typical ns-3 operations on the ghost node if you so desire. The internet stack, for example, must be there and functional on that node in order to participate in IP address assignment and global routing. However, as mentioned above, interfaces talking any Tap Bridge or associated bridged net devices will not work completely. If you understand exactly what you are doing, you can set up other interfaces and devices on the ghost node and use them; or take advantage of the operational send side of the bridged devices to create traffic generators. We generally recommend that you treat this node as a ghost of the Linux host and leave it to itself, though.

Config Paths

ns3::TapBridge is accessible through the following paths with Config::Set and Config::Connect:

/NodeList/[i]/DeviceList/[i]/$ns3::TapBridge

Attributes

Mtu: The MAC-level Maximum Transmission Unit
- Set with class: ns3::UintegerValue
- Underlying type: uint16_t 0:65535
- Initial value: 0
- Flags: construct write read
DeviceName: The name of the tap device to create.
- Set with class: StringValue
- Underlying type: std::string
- Initial value:
- Flags: construct write read
Gateway: The IP address of the default gateway to assign to the host machine, when in ConfigureLocal mode.
- Set with class: Ipv4AddressValue
- Underlying type: Ipv4Address
- Initial value: 255.255.255.255
- Flags: construct write read
IpAddress: The IP address to assign to the tap device, when in ConfigureLocal mode. This address will override the discovered IP address of the simulated device.
- Set with class: Ipv4AddressValue
- Underlying type: Ipv4Address
- Initial value: 255.255.255.255
- Flags: construct write read
MacAddress: The MAC address to assign to the tap device, when in ConfigureLocal mode. This address will override the discovered MAC address of the simulated device.
- Set with class: Mac48AddressValue
- Underlying type: Mac48Address
- Initial value: ff:ff:ff:ff:ff:ff
- Flags: construct write read
Netmask: The network mask to assign to the tap device, when in ConfigureLocal mode. This address will override the discovered MAC address of the simulated device.
- Set with class: Ipv4MaskValue
- Underlying type: Ipv4Mask
- Initial value: 255.255.255.255
- Flags: construct write read
Start: The simulation time at which to spin up the tap device read thread.
- Set with class: ns3::TimeValue
- Underlying type: Time -9223372036854775808.0ns:+9223372036854775807.0ns
- Initial value: +0.0ns
- Flags: construct write read
Stop: The simulation time at which to tear down the tap device read thread.
- Set with class: ns3::TimeValue
- Underlying type: Time -9223372036854775808.0ns:+9223372036854775807.0ns
- Initial value: +0.0ns
- Flags: construct write read
Mode: The operating and configuration mode to use.
- Set with class: ns3::EnumValue
- Underlying type: ConfigureLocal|UseLocal|UseBridge
- Initial value: UseLocal
- Flags: construct write

No TraceSources are defined for this type.

Definition at line 103 of file tap-bridge.h.

Member Enumeration Documentation

enum ns3::TapBridge::Mode

Enumeration of the operating modes supported in the class.

Enumerator
ILLEGAL	mode not set
CONFIGURE_LOCAL	ns-3 creates and configures tap device
USE_LOCAL	ns-3 uses a pre-created tap, without configuring it
USE_BRIDGE	ns-3 uses a pre-created tap, and bridges to a bridging net device

Definition at line 112 of file tap-bridge.h.

Constructor & Destructor Documentation

ns3::TapBridge::TapBridge ( )

Definition at line 139 of file tap-bridge.cc.

References m_packetBuffer, m_tStart, NS_LOG_FUNCTION_NOARGS, and Start().

Here is the call graph for this function:

ns3::TapBridge::~TapBridge ( )

virtual

Definition at line 153 of file tap-bridge.cc.

References m_bridgedDevice, m_packetBuffer, NS_LOG_FUNCTION_NOARGS, and StopTapDevice().

Here is the call graph for this function:

Member Function Documentation

void ns3::TapBridge::AddLinkChangeCallback ( Callback< void > callback )

virtual

Parameters

callback the callback to invoke

Add 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 and by IPv6 stack to flush NDISC cache whenever the link goes up.

Implements ns3::NetDevice.

Definition at line 1081 of file tap-bridge.cc.

References ns3::TracedCallback< T1, T2, T3, T4, T5, T6, T7, T8 >::ConnectWithoutContext(), m_linkChangeCallbacks, and NS_LOG_FUNCTION_NOARGS.

Here is the call graph for this function:

void ns3::TapBridge::CreateTap ( void )

private

Internal:

Call out to a separate process running as suid root in order to get our tap device created. We do this to avoid having the entire simulation running as root. If this method returns, we'll have a socket waiting for us in m_sock that we can use to talk to the tap device.

Definition at line 256 of file tap-bridge.cc.

References first::address, CONFIGURE_LOCAL, ns3::Mac48Address::ConvertFrom(), ns3::Mac48Address::CopyFrom(), GetBridgedNetDevice(), ns3::Object::GetObject(), ns3::Ipv4Mask::GetOnes(), ns3::Mac48Address::IsBroadcast(), ns3::Ipv4Address::IsBroadcast(), ns3::Ipv4Mask::IsEqual(), m_bridgedDevice, m_mode, m_ns3AddressRewritten, m_sock, m_tapDeviceName, m_tapGateway, m_tapIp, m_tapMac, m_tapNetmask, NS_ABORT_MSG_IF, NS_ASSERT_MSG, NS_FATAL_ERROR, NS_LOG_DEBUG, NS_LOG_FUNCTION_NOARGS, NS_LOG_INFO, NS_LOG_WARN, TAP_MAGIC, ns3::TapBufferToString(), USE_BRIDGE, and USE_LOCAL.

Referenced by StartTapDevice().

Here is the call graph for this function:

Here is the caller graph for this function:

bool ns3::TapBridge::DiscardFromBridgedDevice	(	Ptr< NetDevice >	device,
		Ptr< const Packet >	packet,
		uint16_t	protocol,
		Address const &	src
	)

protected

Definition at line 919 of file tap-bridge.cc.

References NS_LOG_FUNCTION, and NS_LOG_LOGIC.

Referenced by SetBridgedNetDevice().

Here is the caller graph for this function:

void ns3::TapBridge::DoDispose ( void )

protectedvirtual

Internal:

Call out to a separate process running as suid root in order to get our tap device created. We do this to avoid having the entire simulation running as root. If this method returns, we'll have a socket waiting for us in m_sock that we can use to talk to the tap device.

Reimplemented from ns3::Object.

Definition at line 166 of file tap-bridge.cc.

References ns3::Object::DoDispose(), and NS_LOG_FUNCTION_NOARGS.

Here is the call graph for this function:

Ptr< Packet > ns3::TapBridge::Filter	(	Ptr< Packet >	packet,
		Address *	src,
		Address *	dst,
		uint16_t *	type
	)

private

Internal:

The host we are bridged to is in the evil real world. Do some sanity checking on a received packet to make sure it isn't too evil for our poor naive virginal simulator to handle.

Parameters

packet	The packet we received from the host, and which we need to check.
src	A pointer to the data structure that will get the source MAC address of the packet (extracted from the packet Ethernet header).
dst	A pointer to the data structure that will get the destination MAC address of the packet (extracted from the packet Ethernet header).
type	A pointer to the variable that will get the packet type from either the Ethernet header in the case of type interpretation (DIX framing) or from the 802.2 LLC header in the case of length interpretation (802.3 framing).

Definition at line 818 of file tap-bridge.cc.

References ns3::EthernetHeader::GetDestination(), ns3::EthernetHeader::GetLengthType(), ns3::LlcSnapHeader::GetSerializedSize(), ns3::EthernetHeader::GetSerializedSize(), ns3::Packet::GetSize(), ns3::EthernetHeader::GetSource(), ns3::LlcSnapHeader::GetType(), NS_LOG_FUNCTION, NS_LOG_LOGIC, and ns3::Packet::RemoveHeader().

Referenced by ForwardToBridgedDevice().

Here is the call graph for this function:

Here is the caller graph for this function:

void ns3::TapBridge::ForwardToBridgedDevice	(	uint8_t *	buf,
		ssize_t	len
	)

private

Definition at line 691 of file tap-bridge.cc.

References CONFIGURE_LOCAL, ns3::Mac48Address::ConvertFrom(), Filter(), m_bridgedDevice, m_mode, m_ns3AddressRewritten, NS_ASSERT_MSG, NS_LOG_FUNCTION, NS_LOG_LOGIC, USE_BRIDGE, and USE_LOCAL.

Referenced by ReadCallback().

Here is the call graph for this function:

Here is the caller graph for this function:

Address ns3::TapBridge::GetAddress ( void ) const

virtual

Returns: the current Address of this interface.

Implements ns3::NetDevice.

Definition at line 1027 of file tap-bridge.cc.

References m_address, and NS_LOG_FUNCTION_NOARGS.

Ptr< NetDevice > ns3::TapBridge::GetBridgedNetDevice ( void )

Get the bridged net device.

The bridged net device is the ns-3 device to which this bridge is connected,

Returns: the bridged net device.

Definition at line 879 of file tap-bridge.cc.

References m_bridgedDevice, and NS_LOG_FUNCTION_NOARGS.

Referenced by CreateTap().

Here is the caller graph for this function:

Address ns3::TapBridge::GetBroadcast ( void ) const

virtual

Returns: the broadcast address supported by this netdevice.

Calling this method is invalid if IsBroadcast returns not true.

Implements ns3::NetDevice.

Definition at line 1095 of file tap-bridge.cc.

References NS_LOG_FUNCTION_NOARGS.

Ptr< Channel > ns3::TapBridge::GetChannel ( void ) const

virtual

Returns: the channel this NetDevice is connected to. The value returned can be zero if the NetDevice is not yet connected to any channel or if the underlying NetDevice has no concept of a channel. i.e., callers must check for zero and be ready to handle it.

Implements ns3::NetDevice.

Definition at line 1013 of file tap-bridge.cc.

References NS_LOG_FUNCTION_NOARGS.

uint32_t ns3::TapBridge::GetIfIndex ( void ) const

virtual

Returns: index ifIndex of the device

Implements ns3::NetDevice.

Definition at line 1006 of file tap-bridge.cc.

References m_ifIndex, and NS_LOG_FUNCTION_NOARGS.

TapBridge::Mode ns3::TapBridge::GetMode ( void )

Get the operating mode of this device.

Returns: The operating mode of this device.

Definition at line 1041 of file tap-bridge.cc.

References m_mode, and NS_LOG_FUNCTION_NOARGS.

uint16_t ns3::TapBridge::GetMtu ( void ) const

virtual

Returns: the link-level MTU in bytes for this interface.

This value is typically used by the IP layer to perform IP fragmentation when needed.

Implements ns3::NetDevice.

Definition at line 1056 of file tap-bridge.cc.

References m_mtu, and NS_LOG_FUNCTION_NOARGS.

Referenced by GetTypeId().

Here is the caller graph for this function:

Address ns3::TapBridge::GetMulticast ( Ipv4Address multicastGroup ) const

virtual

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.

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.

Parameters

multicastGroup The IP address for the multicast group destination of the packet.

Returns: 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 also: Ipv4Address; Address; NetDevice::IsMulticast

Implements ns3::NetDevice.

Definition at line 1109 of file tap-bridge.cc.

References ns3::Mac48Address::GetMulticast(), and NS_LOG_FUNCTION.

Here is the call graph for this function:

Address ns3::TapBridge::GetMulticast ( Ipv6Address addr ) const

virtual

Get the MAC multicast address corresponding to the IPv6 address provided.

Parameters

addr	IPv6 address

Returns: the MAC multicast address

Warning: Calling this method is invalid if IsMulticast returns not true.

Implements ns3::NetDevice.

Definition at line 1194 of file tap-bridge.cc.

References ns3::Mac48Address::GetMulticast(), and NS_LOG_FUNCTION.

Here is the call graph for this function:

Ptr< Node > ns3::TapBridge::GetNode ( void ) const

virtual

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.

Implements ns3::NetDevice.

Definition at line 1153 of file tap-bridge.cc.

References m_node, and NS_LOG_FUNCTION_NOARGS.

Referenced by StartTapDevice().

Here is the caller graph for this function:

TypeId ns3::TapBridge::GetTypeId ( void )

static

Definition at line 80 of file tap-bridge.cc.

References CONFIGURE_LOCAL, GetMtu(), m_tapDeviceName, m_tapGateway, m_tapIp, m_tapMac, m_tapNetmask, m_tStart, m_tStop, ns3::MakeEnumAccessor(), ns3::MakeEnumChecker(), ns3::MakeTimeChecker(), SetMode(), SetMtu(), ns3::TypeId::SetParent(), USE_BRIDGE, and USE_LOCAL.

Here is the call graph for this function:

bool ns3::TapBridge::IsBridge ( void ) const

virtual

Return true if the net device is acting as a bridge.

Returns: value of m_isBridge flag

Implements ns3::NetDevice.

Definition at line 1124 of file tap-bridge.cc.

References NS_LOG_FUNCTION_NOARGS.

bool ns3::TapBridge::IsBroadcast ( void ) const

virtual

Returns: true if this interface supports a broadcast address, false otherwise.

Implements ns3::NetDevice.

Definition at line 1088 of file tap-bridge.cc.

References NS_LOG_FUNCTION_NOARGS.

bool ns3::TapBridge::IsLinkUp ( void ) const

virtual

Returns: true if link is up; false otherwise

Implements ns3::NetDevice.

Definition at line 1074 of file tap-bridge.cc.

References m_linkUp, and NS_LOG_FUNCTION_NOARGS.

bool ns3::TapBridge::IsMulticast ( void ) const

virtual

Returns: value of m_isMulticast flag

Implements ns3::NetDevice.

Definition at line 1102 of file tap-bridge.cc.

References NS_LOG_FUNCTION_NOARGS.

bool ns3::TapBridge::IsPointToPoint ( void ) const

virtual

Return true if the net device is on a point-to-point link.

Returns: value of m_isPointToPoint flag

Implements ns3::NetDevice.

Definition at line 1117 of file tap-bridge.cc.

References NS_LOG_FUNCTION_NOARGS.

bool ns3::TapBridge::NeedsArp ( void ) const

virtual

Returns: true if ARP is needed, false otherwise.

Called by higher-layers to check if this NetDevice requires ARP to be used.

Implements ns3::NetDevice.

Definition at line 1167 of file tap-bridge.cc.

References NS_LOG_FUNCTION_NOARGS.

void ns3::TapBridge::NotifyLinkUp ( void )

private

Definition at line 1063 of file tap-bridge.cc.

References m_linkChangeCallbacks, m_linkUp, and NS_LOG_FUNCTION_NOARGS.

Referenced by StartTapDevice().

Here is the caller graph for this function:

void ns3::TapBridge::ReadCallback	(	uint8_t *	buf,
		ssize_t	len
	)

private

Internal:

Callback to process packets that are read

Definition at line 666 of file tap-bridge.cc.

References ForwardToBridgedDevice(), m_nodeId, ns3::MakeEvent(), NS_ASSERT_MSG, NS_LOG_FUNCTION_NOARGS, NS_LOG_INFO, and ns3::Simulator::ScheduleWithContext().

Referenced by StartTapDevice().

Here is the call graph for this function:

Here is the caller graph for this function:

bool ns3::TapBridge::ReceiveFromBridgedDevice	(	Ptr< NetDevice >	device,
		Ptr< const Packet >	packet,
		uint16_t	protocol,
		Address const &	src,
		Address const &	dst,
		PacketType	packetType
	)

protected

Definition at line 927 of file tap-bridge.cc.

References ns3::Packet::AddHeader(), CONFIGURE_LOCAL, ns3::Mac48Address::ConvertFrom(), ns3::Packet::Copy(), ns3::Packet::CopyData(), ns3::EthernetHeader::GetDestination(), ns3::Node::GetId(), ns3::EthernetHeader::GetLengthType(), ns3::Packet::GetSize(), ns3::EthernetHeader::GetSource(), ns3::Packet::GetUid(), m_bridgedDevice, m_mode, m_node, m_packetBuffer, m_sock, NS_ABORT_MSG_IF, NS_ASSERT_MSG, NS_LOG_DEBUG, NS_LOG_FUNCTION, NS_LOG_LOGIC, ns3::NetDevice::PACKET_OTHERHOST, ns3::EthernetHeader::SetDestination(), ns3::EthernetHeader::SetLengthType(), and ns3::EthernetHeader::SetSource().

Referenced by SetBridgedNetDevice().

Here is the call graph for this function:

Here is the caller graph for this function:

bool ns3::TapBridge::Send	(	Ptr< Packet >	packet,
		const Address &	dest,
		uint16_t	protocolNumber
	)

virtual

Parameters

packet	packet sent from above down to Network Device
dest	mac address of the destination (already resolved)
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

Returns: whether the Send operation succeeded

Implements ns3::NetDevice.

Definition at line 1137 of file tap-bridge.cc.

References NS_FATAL_ERROR, and NS_LOG_FUNCTION.

bool ns3::TapBridge::SendFrom	(	Ptr< Packet >	packet,
		const Address &	source,
		const Address &	dest,
		uint16_t	protocolNumber
	)

virtual

Parameters

packet	packet sent from above down to Network Device
source	source mac address (so called "MAC spoofing")
dest	mac address of the destination (already resolved)
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 with the specified source and destination Addresses.

Returns: whether the Send operation succeeded

Implements ns3::NetDevice.

Definition at line 1145 of file tap-bridge.cc.

References NS_FATAL_ERROR, and NS_LOG_FUNCTION.

void ns3::TapBridge::SetAddress ( Address address )

virtual

Set the address of this interface.

Parameters

address address to set

Implements ns3::NetDevice.

Definition at line 1020 of file tap-bridge.cc.

References ns3::Mac48Address::ConvertFrom(), m_address, and NS_LOG_FUNCTION.

Here is the call graph for this function:

void ns3::TapBridge::SetBridgedNetDevice ( Ptr< NetDevice > bridgedDevice )

Set the ns-3 net device to bridge.

This method tells the bridge which ns-3 net device it should use to connect the simulation side of the bridge.

Parameters

bridgedDevice device to set

Attention: The ns-3 net device that is being set as the device must have an an IP address assigned to it before the simulation is run. This address will be used to set the hardware address of the host Linux device.

Definition at line 886 of file tap-bridge.cc.

References DiscardFromBridgedDevice(), ns3::Mac48Address::IsMatchingType(), m_bridgedDevice, m_mode, m_node, ns3::MakeCallback(), NS_ASSERT_MSG, NS_FATAL_ERROR, NS_LOG_FUNCTION, ReceiveFromBridgedDevice(), and USE_BRIDGE.

Here is the call graph for this function:

void ns3::TapBridge::SetIfIndex ( const uint32_t index )

virtual

Parameters

index ifIndex of the device

Implements ns3::NetDevice.

Definition at line 999 of file tap-bridge.cc.

References m_ifIndex, and NS_LOG_FUNCTION_NOARGS.

void ns3::TapBridge::SetMode ( TapBridge::Mode mode )

Set the operating mode of this device.

Parameters

mode	The operating mode of this device.

Definition at line 1034 of file tap-bridge.cc.

References m_mode, and NS_LOG_FUNCTION.

Referenced by GetTypeId().

Here is the caller graph for this function:

bool ns3::TapBridge::SetMtu ( const uint16_t mtu )

virtual

Parameters

mtu	MTU value, in bytes, to set for the device

Returns: whether the MTU value was within legal bounds

Override for default MTU defined on a per-type basis.

Implements ns3::NetDevice.

Definition at line 1048 of file tap-bridge.cc.

References m_mtu, and NS_LOG_FUNCTION_NOARGS.

Referenced by GetTypeId().

Here is the caller graph for this function:

void ns3::TapBridge::SetNode ( Ptr< Node > node )

virtual

Parameters

node	the node associated to this netdevice.

This method is called from ns3::Node::AddDevice.

Implements ns3::NetDevice.

Definition at line 1160 of file tap-bridge.cc.

References m_node, and NS_LOG_FUNCTION_NOARGS.

void ns3::TapBridge::SetPromiscReceiveCallback ( NetDevice::PromiscReceiveCallback cb )

virtual

Parameters

cb	callback to invoke whenever a packet has been received in promiscuous mode and must be forwarded to the higher layers.

Enables netdevice promiscuous mode and sets the callback that will handle promiscuous mode packets. Note, promiscuous mode packets means all packets, including those packets that can be sensed by the netdevice but which are intended to be received by other hosts.

Implements ns3::NetDevice.

Definition at line 1181 of file tap-bridge.cc.

References m_promiscRxCallback, and NS_LOG_FUNCTION_NOARGS.

void ns3::TapBridge::SetReceiveCallback ( NetDevice::ReceiveCallback cb )

virtual

Parameters

cb	callback to invoke whenever a packet has been received and must be forwarded to the higher layers.

Implements ns3::NetDevice.

Definition at line 1174 of file tap-bridge.cc.

References m_rxCallback, and NS_LOG_FUNCTION_NOARGS.

void ns3::TapBridge::Start ( Time tStart )

Set a start time for the device.

The tap bridge consumes a non-trivial amount of time to start. It starts up in the context of a scheduled event to ensure that all configuration has been completed before extracting the configuration (IP addresses, etc.) In order to allow a more reasonable start-up sequence than a thundering herd of devices, the time at which each device starts is also configurable bot via the Attribute system and via this call.

Parameters

tStart the start time

Definition at line 173 of file tap-bridge.cc.

References ns3::Simulator::Cancel(), m_startEvent, NS_LOG_FUNCTION, ns3::Simulator::Schedule(), and StartTapDevice().

Referenced by TapBridge().

Here is the call graph for this function:

Here is the caller graph for this function:

void ns3::TapBridge::StartTapDevice ( void )

private

Internal:

Spin up the device

Definition at line 196 of file tap-bridge.cc.

References CreateTap(), ns3::Node::GetId(), GetNode(), m_fdReader, m_nodeId, m_sock, ns3::MakeCallback(), NotifyLinkUp(), NS_ABORT_MSG_IF, NS_LOG_FUNCTION_NOARGS, NS_LOG_LOGIC, and ReadCallback().

Referenced by Start().

Here is the call graph for this function:

Here is the caller graph for this function:

void ns3::TapBridge::Stop ( Time tStop )

Set a stop time for the device.

Parameters

tStop the stop time

See also: TapBridge::Start

Definition at line 185 of file tap-bridge.cc.

References ns3::Simulator::Cancel(), m_startEvent, m_stopEvent, NS_LOG_FUNCTION, ns3::Simulator::Schedule(), and StopTapDevice().

Here is the call graph for this function:

void ns3::TapBridge::StopTapDevice ( void )

private

Internal:

Tear down the device

Definition at line 238 of file tap-bridge.cc.

References m_fdReader, m_sock, and NS_LOG_FUNCTION_NOARGS.

Referenced by Stop(), and ~TapBridge().

Here is the caller graph for this function:

bool ns3::TapBridge::SupportsSendFrom ( ) const

virtual

Returns: true if this interface supports a bridging mode, false otherwise.

Implements ns3::NetDevice.

Definition at line 1188 of file tap-bridge.cc.

References NS_LOG_FUNCTION_NOARGS.

Member Data Documentation

Mac48Address ns3::TapBridge::m_address

private

Internal:

The (unused) MAC address of the TapBridge net device. Since the TapBridge is implemented as a ns-3 net device, it is required to implement certain functionality. In this case, the TapBridge is automatically assigned a MAC address, but it is not used.

Definition at line 388 of file tap-bridge.h.

Referenced by GetAddress(), and SetAddress().

Ptr<NetDevice> ns3::TapBridge::m_bridgedDevice

private

Internal:

The ns-3 net device to which we are bridging.

Definition at line 448 of file tap-bridge.h.

Referenced by CreateTap(), ForwardToBridgedDevice(), GetBridgedNetDevice(), ReceiveFromBridgedDevice(), SetBridgedNetDevice(), and ~TapBridge().

Ptr<TapBridgeFdReader> ns3::TapBridge::m_fdReader

private

Internal:

Includes the ns-3 read thread used to do blocking reads on the fd corresponding to the host device.

Definition at line 370 of file tap-bridge.h.

Referenced by StartTapDevice(), and StopTapDevice().

uint32_t ns3::TapBridge::m_ifIndex

private

Internal:

The ns-3 interface index of this TapBridge net device.

Definition at line 331 of file tap-bridge.h.

Referenced by GetIfIndex(), and SetIfIndex().

TracedCallback ns3::TapBridge::m_linkChangeCallbacks

private

Internal:

Callbacks to fire if the link changes state (up or down).

Definition at line 483 of file tap-bridge.h.

Referenced by AddLinkChangeCallback(), and NotifyLinkUp().

bool ns3::TapBridge::m_linkUp

private

Internal:

Flag indicating whether or not the link is up. In this case, whether or not ns-3 is connected to the underlying TAP device with a file descriptor.

Definition at line 476 of file tap-bridge.h.

Referenced by IsLinkUp(), and NotifyLinkUp().

Mode ns3::TapBridge::m_mode

private

Internal:

The operating mode of the bridge. Tells basically who creates and configures the underlying network tap.

Definition at line 378 of file tap-bridge.h.

Referenced by CreateTap(), ForwardToBridgedDevice(), GetMode(), ReceiveFromBridgedDevice(), SetBridgedNetDevice(), and SetMode().

uint16_t ns3::TapBridge::m_mtu

private

Internal:

The common mtu to use for the net devices

Definition at line 338 of file tap-bridge.h.

Referenced by GetMtu(), and SetMtu().

Ptr<Node> ns3::TapBridge::m_node

private

Internal:

Pointer to the (ghost) Node to which we are connected.

Definition at line 323 of file tap-bridge.h.

Referenced by GetNode(), ReceiveFromBridgedDevice(), SetBridgedNetDevice(), and SetNode().

uint32_t ns3::TapBridge::m_nodeId

private

Definition at line 467 of file tap-bridge.h.

Referenced by ReadCallback(), and StartTapDevice().

bool ns3::TapBridge::m_ns3AddressRewritten

private

Internal:

Whether the MAC address of the underlying ns-3 device has already been rewritten is stored in this variable (for UseLocal/UseBridge mode only).

Definition at line 455 of file tap-bridge.h.

Referenced by CreateTap(), and ForwardToBridgedDevice().

uint8_t* ns3::TapBridge::m_packetBuffer

private

A 64K buffer to hold packet data while it is being sent.

Definition at line 460 of file tap-bridge.h.

Referenced by ReceiveFromBridgedDevice(), TapBridge(), and ~TapBridge().

NetDevice::PromiscReceiveCallback ns3::TapBridge::m_promiscRxCallback

private

Internal:

Callback used to hook the promiscuous packet receive callback of the TapBridge ns-3 net device. This is never called, and therefore no packets will ever be received forwarded up the IP stack on the ghost node through this device.

Note that we intercept the similar callback in the bridged device in order to do the actual bridging between the bridged ns-3 net device and the Tap device on the host.

Definition at line 316 of file tap-bridge.h.

Referenced by SetPromiscReceiveCallback().

NetDevice::ReceiveCallback ns3::TapBridge::m_rxCallback

private

Internal:

Callback used to hook the standard packet receive callback of the TapBridge ns-3 net device. This is never called, and therefore no packets will ever be received forwarded up the IP stack on the ghost node through this device.

Definition at line 303 of file tap-bridge.h.

Referenced by SetReceiveCallback().

int ns3::TapBridge::m_sock

private

Internal:

The socket (actually interpreted as fd) to use to talk to the Tap device on the real internet host.

Definition at line 346 of file tap-bridge.h.

Referenced by CreateTap(), ReceiveFromBridgedDevice(), StartTapDevice(), and StopTapDevice().

EventId ns3::TapBridge::m_startEvent

private

Internal:

The ID of the ns-3 event used to schedule the start up of the underlying host Tap device and ns-3 read thread.

Definition at line 354 of file tap-bridge.h.

Referenced by Start(), and Stop().

EventId ns3::TapBridge::m_stopEvent

private

Internal:

The ID of the ns-3 event used to schedule the tear down of the underlying host Tap device and ns-3 read thread.

Definition at line 362 of file tap-bridge.h.

Referenced by Stop().

std::string ns3::TapBridge::m_tapDeviceName

private

Internal:

The name of the device to create on the host. If the device name is the empty string, we allow the host kernel to choose a name.

Definition at line 410 of file tap-bridge.h.

Referenced by CreateTap(), and GetTypeId().

Ipv4Address ns3::TapBridge::m_tapGateway

private

Internal:

The IP address to use as the device default gateway on the host.

Definition at line 417 of file tap-bridge.h.

Referenced by CreateTap(), and GetTypeId().

Ipv4Address ns3::TapBridge::m_tapIp

private

Internal:

The IP address to use as the device IP on the host.

Definition at line 424 of file tap-bridge.h.

Referenced by CreateTap(), and GetTypeId().

Mac48Address ns3::TapBridge::m_tapMac

private

Internal:

The MAC address to use as the hardware address on the host; only used in UseLocal mode. This value comes from the MAC address assigned to the bridged ns-3 net device and matches the MAC address of the underlying network TAP which we configured to have the same value.

Definition at line 434 of file tap-bridge.h.

Referenced by CreateTap(), and GetTypeId().

Ipv4Mask ns3::TapBridge::m_tapNetmask

private

Internal:

The network mask to assign to the device created on the host.

Definition at line 441 of file tap-bridge.h.

Referenced by CreateTap(), and GetTypeId().

Time ns3::TapBridge::m_tStart

private

Internal:

Time to start spinning up the device

Definition at line 395 of file tap-bridge.h.

Referenced by GetTypeId(), and TapBridge().

Time ns3::TapBridge::m_tStop

private

Internal:

Time to start tearing down the device

Definition at line 402 of file tap-bridge.h.

Referenced by GetTypeId().

The documentation for this class was generated from the following files:

src/tap-bridge/model/tap-bridge.h
src/tap-bridge/model/tap-bridge.cc

Public Types

Public Member Functions

Static Public Member Functions

Protected Member Functions

Private Member Functions

Private Attributes

Detailed Description

Config Paths

Attributes

Member Enumeration Documentation

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation