NS3中的UdpL4Protocol类
这个类继承于IpL4Protocol类。
这个类保有以下几个私有变量。
Ptr<Node> m_node; //!< the node this stack is associated with
Ipv4EndPointDemux *m_endPoints; //!< A list of IPv4 end points.
Ipv6EndPointDemux *m_endPoints6; //!< A list of IPv6 end points.
/**
* \brief Copy constructor
*
* Defined and not implemented to avoid misuse
*/
UdpL4Protocol (const UdpL4Protocol &);
/**
* \brief Copy constructor
*
* Defined and not implemented to avoid misuse
* \returns
*/
UdpL4Protocol &operator = (const UdpL4Protocol &);
std::vector<Ptr<UdpSocketImpl> > m_sockets; //!< list of sockets
IpL4Protocol::DownTargetCallback m_downTarget; //!< Callback to send packets over IPv4
IpL4Protocol::DownTargetCallback6 m_downTarget6; //!< Callback to send packets over IPv6
我们可以注意到，这个类中并没有保有设备信息，这说明这是设备无关的，但是这是节点相关的，也就是其需要保有一个和主机相关的主机号。
Ipv4EndPointDemux类是一个连接的集合。这个类保有这个变量并不奇怪，因为一台主机可以同时有多个连接。m_sockets中保有了所有socket的集合，而m_downTarget设置了当需要发送包时，应当如何执行动作。
下面可以看一下这个类中定义并实现了哪些函数：
namespace ns3 {
NS_LOG_COMPONENT_DEFINE ("UdpL4Protocol");
NS_OBJECT_ENSURE_REGISTERED (UdpL4Protocol);
/* see http://www.iana.org/assignments/protocol-numbers */
const uint8_t UdpL4Protocol::PROT_NUMBER = 17;
TypeId
UdpL4Protocol::GetTypeId (void)
{
static TypeId tid = TypeId ("ns3::UdpL4Protocol")
.SetParent<IpL4Protocol> ()
.SetGroupName ("Internet")
.AddConstructor<UdpL4Protocol> ()
.AddAttribute ("SocketList", "The list of sockets associated to this protocol.",
ObjectVectorValue (),
MakeObjectVectorAccessor (&UdpL4Protocol::m_sockets),
MakeObjectVectorChecker<UdpSocketImpl> ())
;
return tid;
}
UdpL4Protocol::UdpL4Protocol ()
: m_endPoints (new Ipv4EndPointDemux ()), m_endPoints6 (new Ipv6EndPointDemux ())
{
NS_LOG_FUNCTION_NOARGS ();
}
UdpL4Protocol::~UdpL4Protocol ()
{
NS_LOG_FUNCTION_NOARGS ();
}
void
UdpL4Protocol::SetNode (Ptr<Node> node)
{
m_node = node;
}
/*
* This method is called by AddAgregate and completes the aggregation
* by setting the node in the udp stack and link it to the ipv4 object
* present in the node along with the socket factory
*/
void
UdpL4Protocol::NotifyNewAggregate ()
{
NS_LOG_FUNCTION (this);
Ptr<Node> node = this->GetObject<Node> ();
Ptr<Ipv4> ipv4 = this->GetObject<Ipv4> ();
Ptr<Ipv6> ipv6 = node->GetObject<Ipv6> ();
if (m_node == 0)
{
if ((node != 0) && (ipv4 != 0 || ipv6 != 0))
{
this->SetNode (node);
Ptr<UdpSocketFactoryImpl> udpFactory = CreateObject<UdpSocketFactoryImpl> ();
udpFactory->SetUdp (this);
node->AggregateObject (udpFactory);
}
}
// We set at least one of our 2 down targets to the IPv4/IPv6 send
// functions. Since these functions have different prototypes, we
// need to keep track of whether we are connected to an IPv4 or
// IPv6 lower layer and call the appropriate one.
if (ipv4 != 0 && m_downTarget.IsNull())
{
ipv4->Insert (this);
this->SetDownTarget (MakeCallback (&Ipv4::Send, ipv4));
}
if (ipv6 != 0 && m_downTarget6.IsNull())
{
ipv6->Insert (this);
this->SetDownTarget6 (MakeCallback (&Ipv6::Send, ipv6));
}
IpL4Protocol::NotifyNewAggregate ();
}
int
UdpL4Protocol::GetProtocolNumber (void) const
{
return PROT_NUMBER;
}
void
UdpL4Protocol::DoDispose (void)
{
NS_LOG_FUNCTION_NOARGS ();
for (std::vector<Ptr<UdpSocketImpl> >::iterator i = m_sockets.begin (); i != m_sockets.end (); i++)
{
*i = 0;
}
m_sockets.clear ();
if (m_endPoints != 0)
{
delete m_endPoints;
m_endPoints = 0;
}
if (m_endPoints6 != 0)
{
delete m_endPoints6;
m_endPoints6 = 0;
}
m_node = 0;
m_downTarget.Nullify ();
m_downTarget6.Nullify ();
/*
= MakeNullCallback<void,Ptr<Packet>, Ipv4Address, Ipv4Address, uint8_t, Ptr<Ipv4Route> > ();
*/
IpL4Protocol::DoDispose ();
}
Ptr<Socket>
UdpL4Protocol::CreateSocket (void)
{
NS_LOG_FUNCTION_NOARGS ();
Ptr<UdpSocketImpl> socket = CreateObject<UdpSocketImpl> ();
socket->SetNode (m_node);
socket->SetUdp (this);
m_sockets.push_back (socket);
return socket;
}
Ipv4EndPoint *
UdpL4Protocol::Allocate (void)
{
NS_LOG_FUNCTION (this);
return m_endPoints->Allocate ();
}
Ipv4EndPoint *
UdpL4Protocol::Allocate (Ipv4Address address)
{
NS_LOG_FUNCTION (this << address);
return m_endPoints->Allocate (address);
}
Ipv4EndPoint *
UdpL4Protocol::Allocate (Ptr<NetDevice> boundNetDevice, uint16_t port)
{
NS_LOG_FUNCTION (this << boundNetDevice << port);
return m_endPoints->Allocate (boundNetDevice, port);
}
Ipv4EndPoint *
UdpL4Protocol::Allocate (Ptr<NetDevice> boundNetDevice, Ipv4Address address, uint16_t port)
{
NS_LOG_FUNCTION (this << boundNetDevice << address << port);
return m_endPoints->Allocate (boundNetDevice, address, port);
}
Ipv4EndPoint *
UdpL4Protocol::Allocate (Ptr<NetDevice> boundNetDevice,
Ipv4Address localAddress, uint16_t localPort,
Ipv4Address peerAddress, uint16_t peerPort)
{
NS_LOG_FUNCTION (this << boundNetDevice << localAddress << localPort << peerAddress << peerPort);
return m_endPoints->Allocate (boundNetDevice,
localAddress, localPort,
peerAddress, peerPort);
}
void
UdpL4Protocol::DeAllocate (Ipv4EndPoint *endPoint)
{
NS_LOG_FUNCTION (this << endPoint);
m_endPoints->DeAllocate (endPoint);
}
Ipv6EndPoint *
UdpL4Protocol::Allocate6 (void)
{
NS_LOG_FUNCTION (this);
return m_endPoints6->Allocate ();
}
Ipv6EndPoint *
UdpL4Protocol::Allocate6 (Ipv6Address address)
{
NS_LOG_FUNCTION (this << address);
return m_endPoints6->Allocate (address);
}
Ipv6EndPoint *
UdpL4Protocol::Allocate6 (Ptr<NetDevice> boundNetDevice, uint16_t port)
{
NS_LOG_FUNCTION (this << boundNetDevice << port);
return m_endPoints6->Allocate (boundNetDevice, port);
}
Ipv6EndPoint *
UdpL4Protocol::Allocate6 (Ptr<NetDevice> boundNetDevice, Ipv6Address address, uint16_t port)
{
NS_LOG_FUNCTION (this << boundNetDevice << address << port);
return m_endPoints6->Allocate (boundNetDevice, address, port);
}
Ipv6EndPoint *
UdpL4Protocol::Allocate6 (Ptr<NetDevice> boundNetDevice,
Ipv6Address localAddress, uint16_t localPort,
Ipv6Address peerAddress, uint16_t peerPort)
{
NS_LOG_FUNCTION (this << boundNetDevice << localAddress << localPort << peerAddress << peerPort);
return m_endPoints6->Allocate (boundNetDevice,
localAddress, localPort,
peerAddress, peerPort);
}
void
UdpL4Protocol::DeAllocate (Ipv6EndPoint *endPoint)
{
NS_LOG_FUNCTION (this << endPoint);
m_endPoints6->DeAllocate (endPoint);
}
void
UdpL4Protocol::ReceiveIcmp (Ipv4Address icmpSource, uint8_t icmpTtl,
uint8_t icmpType, uint8_t icmpCode, uint32_t icmpInfo,
Ipv4Address payloadSource,Ipv4Address payloadDestination,
const uint8_t payload[8])
{
NS_LOG_FUNCTION (this << icmpSource << icmpTtl << icmpType << icmpCode << icmpInfo
<< payloadSource << payloadDestination);
uint16_t src, dst;
src = payload[0] << 8;
src |= payload[1];
dst = payload[2] << 8;
dst |= payload[3];
Ipv4EndPoint *endPoint = m_endPoints->SimpleLookup (payloadSource, src, payloadDestination, dst);
if (endPoint != 0)
{
endPoint->ForwardIcmp (icmpSource, icmpTtl, icmpType, icmpCode, icmpInfo);
}
else
{
NS_LOG_DEBUG ("no endpoint found source=" << payloadSource <<
", destination="<<payloadDestination<<
", src=" << src << ", dst=" << dst);
}
}
void
UdpL4Protocol::ReceiveIcmp (Ipv6Address icmpSource, uint8_t icmpTtl,
uint8_t icmpType, uint8_t icmpCode, uint32_t icmpInfo,
Ipv6Address payloadSource,Ipv6Address payloadDestination,
const uint8_t payload[8])
{
NS_LOG_FUNCTION (this << icmpSource << icmpTtl << icmpType << icmpCode << icmpInfo
<< payloadSource << payloadDestination);
uint16_t src, dst;
src = payload[0] << 8;
src |= payload[1];
dst = payload[2] << 8;
dst |= payload[3];
Ipv6EndPoint *endPoint = m_endPoints6->SimpleLookup (payloadSource, src, payloadDestination, dst);
if (endPoint != 0)
{
endPoint->ForwardIcmp (icmpSource, icmpTtl, icmpType, icmpCode, icmpInfo);
}
else
{
NS_LOG_DEBUG ("no endpoint found source=" << payloadSource <<
", destination="<<payloadDestination<<
", src=" << src << ", dst=" << dst);
}
}
enum IpL4Protocol::RxStatus
UdpL4Protocol::Receive (Ptr<Packet> packet,
Ipv4Header const &header,
Ptr<Ipv4Interface> interface)
{
NS_LOG_FUNCTION (this << packet << header);
UdpHeader udpHeader;
if(Node::ChecksumEnabled ())
{
udpHeader.EnableChecksums ();
}
udpHeader.InitializeChecksum (header.GetSource (), header.GetDestination (), PROT_NUMBER);
// We only peek at the header for now (instead of removing it) so that it will be intact
// if we have to pass it to a IPv6 endpoint via:
//
// UdpL4Protocol::Receive (Ptr<Packet> packet, Ipv6Address &src, Ipv6Address &dst, ...)
packet->PeekHeader (udpHeader);
if(!udpHeader.IsChecksumOk ())
{
NS_LOG_INFO ("Bad checksum : dropping packet!");
return IpL4Protocol::RX_CSUM_FAILED;
}
NS_LOG_DEBUG ("Looking up dst " << header.GetDestination () << " port " << udpHeader.GetDestinationPort ());
Ipv4EndPointDemux::EndPoints endPoints =
m_endPoints->Lookup (header.GetDestination (), udpHeader.GetDestinationPort (),
header.GetSource (), udpHeader.GetSourcePort (), interface);
if (endPoints.empty ())
{
if (this->GetObject<Ipv6L3Protocol> () != 0)
{
NS_LOG_LOGIC (" No Ipv4 endpoints matched on UdpL4Protocol, trying Ipv6 "<<this);
Ptr<Ipv6Interface> fakeInterface;
Ipv6Header ipv6Header;
Ipv6Address src = Ipv6Address::MakeIpv4MappedAddress (header.GetSource ());
Ipv6Address dst = Ipv6Address::MakeIpv4MappedAddress (header.GetDestination ());
ipv6Header.SetSourceAddress (src);
ipv6Header.SetDestinationAddress (dst);
return (this->Receive (packet, ipv6Header, fakeInterface));
}
NS_LOG_LOGIC ("RX_ENDPOINT_UNREACH");
return IpL4Protocol::RX_ENDPOINT_UNREACH;
}
packet->RemoveHeader(udpHeader);
for (Ipv4EndPointDemux::EndPointsI endPoint = endPoints.begin ();
endPoint != endPoints.end (); endPoint++)
{
(*endPoint)->ForwardUp (packet->Copy (), header, udpHeader.GetSourcePort (),
interface);
}
return IpL4Protocol::RX_OK;
}
enum IpL4Protocol::RxStatus
UdpL4Protocol::Receive (Ptr<Packet> packet,
Ipv6Header const &header,
Ptr<Ipv6Interface> interface)
{
NS_LOG_FUNCTION (this << packet << header.GetSourceAddress () << header.GetDestinationAddress ());
UdpHeader udpHeader;
if(Node::ChecksumEnabled ())
{
udpHeader.EnableChecksums ();
}
udpHeader.InitializeChecksum (header.GetSourceAddress (), header.GetDestinationAddress (), PROT_NUMBER);
packet->RemoveHeader (udpHeader);
if(!udpHeader.IsChecksumOk () && !header.GetSourceAddress ().IsIpv4MappedAddress ())
{
NS_LOG_INFO ("Bad checksum : dropping packet!");
return IpL4Protocol::RX_CSUM_FAILED;
}
NS_LOG_DEBUG ("Looking up dst " << header.GetDestinationAddress () << " port " << udpHeader.GetDestinationPort ());
Ipv6EndPointDemux::EndPoints endPoints =
m_endPoints6->Lookup (header.GetDestinationAddress (), udpHeader.GetDestinationPort (),
header.GetSourceAddress (), udpHeader.GetSourcePort (), interface);
if (endPoints.empty ())
{
NS_LOG_LOGIC ("RX_ENDPOINT_UNREACH");
return IpL4Protocol::RX_ENDPOINT_UNREACH;
}
for (Ipv6EndPointDemux::EndPointsI endPoint = endPoints.begin ();
endPoint != endPoints.end (); endPoint++)
{
(*endPoint)->ForwardUp (packet->Copy (), header, udpHeader.GetSourcePort (), interface);
}
return IpL4Protocol::RX_OK;
}
void
UdpL4Protocol::Send (Ptr<Packet> packet,
Ipv4Address saddr, Ipv4Address daddr,
uint16_t sport, uint16_t dport)
{
NS_LOG_FUNCTION (this << packet << saddr << daddr << sport << dport);
UdpHeader udpHeader;
if(Node::ChecksumEnabled ())
{
udpHeader.EnableChecksums ();
udpHeader.InitializeChecksum (saddr,
daddr,
PROT_NUMBER);
}
udpHeader.SetDestinationPort (dport);
udpHeader.SetSourcePort (sport);
packet->AddHeader (udpHeader);
m_downTarget (packet, saddr, daddr, PROT_NUMBER, 0);
}
void
UdpL4Protocol::Send (Ptr<Packet> packet,
Ipv4Address saddr, Ipv4Address daddr,
uint16_t sport, uint16_t dport, Ptr<Ipv4Route> route)
{
NS_LOG_FUNCTION (this << packet << saddr << daddr << sport << dport << route);
UdpHeader udpHeader;
if(Node::ChecksumEnabled ())
{
udpHeader.EnableChecksums ();
udpHeader.InitializeChecksum (saddr,
daddr,
PROT_NUMBER);
}
udpHeader.SetDestinationPort (dport);
udpHeader.SetSourcePort (sport);
packet->AddHeader (udpHeader);
m_downTarget (packet, saddr, daddr, PROT_NUMBER, route);
}
void
UdpL4Protocol::Send (Ptr<Packet> packet,
Ipv6Address saddr, Ipv6Address daddr,
uint16_t sport, uint16_t dport)
{
NS_LOG_FUNCTION (this << packet << saddr << daddr << sport << dport);
UdpHeader udpHeader;
if(Node::ChecksumEnabled ())
{
udpHeader.EnableChecksums ();
udpHeader.InitializeChecksum (saddr,
daddr,
PROT_NUMBER);
}
udpHeader.SetDestinationPort (dport);
udpHeader.SetSourcePort (sport);
packet->AddHeader (udpHeader);
m_downTarget6 (packet, saddr, daddr, PROT_NUMBER, 0);
}
void
UdpL4Protocol::Send (Ptr<Packet> packet,
Ipv6Address saddr, Ipv6Address daddr,
uint16_t sport, uint16_t dport, Ptr<Ipv6Route> route)
{
NS_LOG_FUNCTION (this << packet << saddr << daddr << sport << dport << route);
UdpHeader udpHeader;
if(Node::ChecksumEnabled ())
{
udpHeader.EnableChecksums ();
udpHeader.InitializeChecksum (saddr,
daddr,
PROT_NUMBER);
}
udpHeader.SetDestinationPort (dport);
udpHeader.SetSourcePort (sport);
packet->AddHeader (udpHeader);
m_downTarget6 (packet, saddr, daddr, PROT_NUMBER, route);
}
void
UdpL4Protocol::SetDownTarget (IpL4Protocol::DownTargetCallback callback)
{
NS_LOG_FUNCTION (this);
m_downTarget = callback;
}
IpL4Protocol::DownTargetCallback
UdpL4Protocol::GetDownTarget (void) const
{
return m_downTarget;
}
void
UdpL4Protocol::SetDownTarget6 (IpL4Protocol::DownTargetCallback6 callback)
{
NS_LOG_FUNCTION (this);
m_downTarget6 = callback;
}
IpL4Protocol::DownTargetCallback6
UdpL4Protocol::GetDownTarget6 (void) const
{
return m_downTarget6;
}
} // namespace ns3
参考文献
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