inet::Ppp Class Reference

PPP implementation. More...

#include <Ppp.h>

Inheritance diagram for inet::Ppp:

Public Member Functions
virtual	~Ppp ()
virtual queueing::IPassivePacketSource *	getProvider (cGate *gate) override
	Returns the passive packet source from where packets are pulled or nullptr if the connected module doesn't implement the interface. More...
virtual void	handleCanPullPacketChanged (cGate *gate) override
	Notifies about a change in the possibility of pulling some packet from the passive packet source at the given gate. More...
virtual void	handlePullPacketProcessed (Packet *packet, cGate *gate, bool successful) override
	Notifies about the completion of the packet processing for a packet that was pulled earlier independently whether the packet is passed or streamed. More...
Public Member Functions inherited from inet::OperationalMixin< cSimpleModule >
virtual	~OperationalMixin ()
	}@ More...
Public Member Functions inherited from inet::ILifecycle
virtual	~ILifecycle ()
Public Member Functions inherited from inet::queueing::IActivePacketSink
virtual	~IActivePacketSink ()

Protected Member Functions
virtual void	startTransmitting ()
virtual void	encapsulate (Packet *msg)
virtual void	decapsulate (Packet *packet)
virtual void	refreshDisplay () const override
virtual void	refreshOutGateConnection (bool connected)
virtual void	receiveSignal (cComponent *source, simsignal_t signalID, cObject *obj, cObject *details) override
virtual void	configureNetworkInterface () override
virtual int	numInitStages () const override
virtual void	initialize (int stage) override
virtual void	handleMessageWhenUp (cMessage *message) override
virtual void	handleSelfMessage (cMessage *message) override
virtual void	handleUpperPacket (Packet *packet) override
virtual void	handleLowerPacket (Packet *packet) override
virtual void	handleStopOperation (LifecycleOperation *operation) override
virtual void	processUpperPacket ()
Protected Member Functions inherited from inet::MacProtocolBase
	MacProtocolBase ()
virtual	~MacProtocolBase ()
virtual void	registerInterface ()
virtual MacAddress	parseMacAddressParameter (const char *addrstr)
virtual void	deleteCurrentTxFrame ()
virtual void	dropCurrentTxFrame (PacketDropDetails &details)
virtual void	handleMessageWhenDown (cMessage *msg) override
virtual void	sendUp (cMessage *message)
virtual void	sendDown (cMessage *message)
virtual bool	isUpperMessage (cMessage *message) const override
virtual bool	isLowerMessage (cMessage *message) const override
virtual bool	isInitializeStage (int stage) const override
virtual bool	isModuleStartStage (int stage) const override
virtual bool	isModuleStopStage (int stage) const override
virtual void	flushQueue (PacketDropDetails &details)
	should clear queue and emit signal "packetDropped" with entire packets More...
virtual void	clearQueue ()
	should clear queue silently More...
virtual void	handleStartOperation (LifecycleOperation *operation) override
virtual void	handleCrashOperation (LifecycleOperation *operation) override
queueing::IPacketQueue *	getQueue (cGate *gate) const
virtual bool	canDequeuePacket () const
virtual Packet *	dequeuePacket ()
Protected Member Functions inherited from inet::LayeredProtocolBase
virtual void	handleUpperMessage (cMessage *message)
virtual void	handleLowerMessage (cMessage *message)
virtual void	handleUpperCommand (cMessage *message)
virtual void	handleLowerCommand (cMessage *message)
Protected Member Functions inherited from inet::OperationalMixin< cSimpleModule >
virtual int	numInitStages () const override
virtual void	refreshDisplay () const override
virtual void	handleMessage (cMessage *msg) override
virtual bool	handleOperationStage (LifecycleOperation *operation, IDoneCallback *doneCallback) override
	Perform one stage of a lifecycle operation. More...
virtual State	getInitialOperationalState () const
	Returns initial operational state: OPERATING or NOT_OPERATING. More...
virtual void	handleActiveOperationTimeout (cMessage *message)
virtual bool	isUp () const
	utility functions More...
virtual bool	isDown () const
virtual void	setOperationalState (State newState)
virtual void	scheduleOperationTimeout (simtime_t timeout)
virtual void	setupActiveOperation (LifecycleOperation *operation, IDoneCallback *doneCallback, State)
virtual void	delayActiveOperationFinish (simtime_t timeout)
virtual void	startActiveOperationExtraTime (simtime_t delay=SIMTIME_ZERO)
virtual void	startActiveOperationExtraTimeOrFinish (simtime_t extraTime)
virtual void	finishActiveOperation ()

Protected Attributes
const char *	displayStringTextFormat = nullptr
bool	sendRawBytes = false
cGate *	physOutGate = nullptr
cChannel *	datarateChannel = nullptr
cMessage *	endTransmissionEvent = nullptr
Packet *	curTxPacket = nullptr
std::string	oldConnColor
long	numSent = 0
long	numRcvdOK = 0
long	numDroppedBitErr = 0
long	numDroppedIfaceDown = 0
Protected Attributes inherited from inet::MacProtocolBase
int	upperLayerInGateId = -1
	Gate ids. More...
int	upperLayerOutGateId = -1
int	lowerLayerInGateId = -1
int	lowerLayerOutGateId = -1
opp_component_ptr< NetworkInterface >	networkInterface
opp_component_ptr< cModule >	hostModule
Packet *	currentTxFrame = nullptr
	Currently transmitted frame if any. More...
opp_component_ptr< queueing::IPacketQueue >	txQueue
	Messages received from upper layer and to be transmitted later. More...
Protected Attributes inherited from inet::OperationalMixin< cSimpleModule >
State	operationalState
simtime_t	lastChange
Operation	activeOperation
cMessage *	activeOperationTimeout
cMessage *	activeOperationExtraTimer

Static Protected Attributes
static simsignal_t	transmissionStateChangedSignal = registerSignal("transmissionStateChanged")
static simsignal_t	rxPkOkSignal = registerSignal("rxPkOk")

Additional Inherited Members
Protected Types inherited from inet::OperationalMixin< cSimpleModule >
enum	State

Detailed Description

PPP implementation.

Constructor & Destructor Documentation

~Ppp()

inet::Ppp::~Ppp ( )

virtual

{
    cancelAndDelete(endTransmissionEvent);
    delete curTxPacket;
}

Member Function Documentation

configureNetworkInterface()

void inet::Ppp::configureNetworkInterface ( )

overrideprotectedvirtual

Implements inet::MacProtocolBase.

{
    // data rate
    bool connected = datarateChannel != nullptr;
    double datarate = connected ? datarateChannel->getNominalDatarate() : 0;
    networkInterface->setDatarate(datarate);
    networkInterface->setCarrier(connected);
 
    // generate a link-layer address to be used as interface token for IPv6
    InterfaceToken token(0, getSimulation()->getUniqueNumber(), 64);
    networkInterface->setInterfaceToken(token);
 
    // MTU: typical values are 576 (Internet de facto), 1500 (Ethernet-friendly),
    // 4000 (on some point-to-point links), 4470 (Cisco routers default, FDDI compatible)
    networkInterface->setMtu(par("mtu"));
 
    // capabilities
    networkInterface->setMulticast(true);
    networkInterface->setPointToPoint(true);
}

decapsulate()

void inet::Ppp::decapsulate ( Packet *  packet )

protectedvirtual

{
    const auto& pppHeader = packet->popAtFront<PppHeader>();
    const auto& pppTrailer = packet->popAtBack<PppTrailer>(PPP_TRAILER_LENGTH);
    if (pppHeader == nullptr || pppTrailer == nullptr)
        throw cRuntimeError("Invalid PPP packet: PPP header or Trailer is missing");
    // TODO check CRC
    packet->addTagIfAbsent<InterfaceInd>()->setInterfaceId(networkInterface->getInterfaceId());
 
    auto payloadProtocol = ProtocolGroup::pppprotocol.getProtocol(pppHeader->getProtocol());
    packet->addTagIfAbsent<DispatchProtocolReq>()->setProtocol(payloadProtocol);
    packet->addTagIfAbsent<PacketProtocolTag>()->setProtocol(payloadProtocol);
}

Referenced by handleLowerPacket().

encapsulate()

void inet::Ppp::encapsulate ( Packet *  msg )

protectedvirtual

{
    auto pppHeader = makeShared<PppHeader>();
    pppHeader->setProtocol(ProtocolGroup::pppprotocol.getProtocolNumber(packet->getTag<PacketProtocolTag>()->getProtocol()));
    packet->insertAtFront(pppHeader);
    auto pppTrailer = makeShared<PppTrailer>();
    packet->insertAtBack(pppTrailer);
    packet->addTagIfAbsent<PacketProtocolTag>()->setProtocol(&Protocol::ppp);
}

Referenced by startTransmitting().

getProvider()

queueing::IPassivePacketSource * inet::Ppp::getProvider ( cGate *  gate )

overridevirtual

Returns the passive packet source from where packets are pulled or nullptr if the connected module doesn't implement the interface.

The gate parameter must be a valid gate of this module.

Implements inet::queueing::IActivePacketSink.

{
    return (gate->getId() == upperLayerInGateId) ? txQueue.get() : nullptr;
}

handleCanPullPacketChanged()

void inet::Ppp::handleCanPullPacketChanged ( cGate *  gate )

overridevirtual

Notifies about a change in the possibility of pulling some packet from the passive packet source at the given gate.

This method is called, for example, when a new packet is inserted into a queue. It allows the sink to pull a new packet from the queue.

The gate parameter must be a valid gate of this module.

Implements inet::queueing::IActivePacketSink.

{
    Enter_Method("handleCanPullPacketChanged");
    while (currentTxFrame == nullptr && canDequeuePacket())
        processUpperPacket();
}

handleLowerPacket()

void inet::Ppp::handleLowerPacket ( Packet *  packet )

overrideprotectedvirtual

Reimplemented from inet::LayeredProtocolBase.

{
    // TODO if incoming gate is not connected now, then the link has been deleted
    // during packet transmission --> discard incomplete packet.
    EV_INFO << "Received " << packet << " from network.\n";
    packet->addTagIfAbsent<PacketProtocolTag>()->setProtocol(&Protocol::ppp);
 
    // check for bit errors
    if (packet->hasBitError()) {
        EV_WARN << "Bit error in " << packet << endl;
        PacketDropDetails details;
        details.setReason(INCORRECTLY_RECEIVED);
        emit(packetDroppedSignal, packet, &details);
        numDroppedBitErr++;
        delete packet;
    }
    else {
        // pass up payload
        const auto& pppHeader = packet->peekAtFront<PppHeader>();
        const auto& pppTrailer = packet->peekAtBack<PppTrailer>(PPP_TRAILER_LENGTH);
        if (pppHeader == nullptr || pppTrailer == nullptr)
            throw cRuntimeError("Invalid PPP packet: PPP header or Trailer is missing");
        emit(rxPkOkSignal, packet);
        decapsulate(packet);
        numRcvdOK++;
        emit(packetSentToUpperSignal, packet);
        EV_INFO << "Sending " << packet << " to upper layer.\n";
        send(packet, "upperLayerOut");
    }
}

handleMessageWhenUp()

void inet::Ppp::handleMessageWhenUp ( cMessage *  message )

overrideprotectedvirtual

Reimplemented from inet::LayeredProtocolBase.

{
    MacProtocolBase::handleMessageWhenUp(message);
    if (operationalState == State::STOPPING_OPERATION) {
        if (txQueue->isEmpty()) {
            networkInterface->setCarrier(false);
            networkInterface->setState(NetworkInterface::State::DOWN);
            startActiveOperationExtraTimeOrFinish(par("stopOperationExtraTime"));
        }
    }
}

handlePullPacketProcessed()

void inet::Ppp::handlePullPacketProcessed ( Packet *  packet, cGate *  gate, bool  successful  )

overridevirtual

Notifies about the completion of the packet processing for a packet that was pulled earlier independently whether the packet is passed or streamed.

This method is called, for example, when a previously pulled packet is failed to be processed successfully. It allows the sink to retry the operation.

The gate parameter must be a valid gate of this module. The packet must not be nullptr.

Implements inet::queueing::IActivePacketSink.

{
    Enter_Method("handlePullPacketProcessed");
    throw cRuntimeError("Not supported callback");
}

handleSelfMessage()

void inet::Ppp::handleSelfMessage ( cMessage *  message )

overrideprotectedvirtual

Reimplemented from inet::LayeredProtocolBase.

{
    if (message == endTransmissionEvent) {
        deleteCurrentTxFrame();
        delete curTxPacket;
        curTxPacket = nullptr;
        // Transmission finished, we can start next one.
        EV_INFO << "Transmission successfully completed.\n";
        emit(transmissionStateChangedSignal, 0L);
        if (canDequeuePacket())
            processUpperPacket();
    }
    else
        throw cRuntimeError("Unknown self message");
}

handleStopOperation()

void inet::Ppp::handleStopOperation ( LifecycleOperation *  operation )

overrideprotectedvirtual

Reimplemented from inet::MacProtocolBase.

{
    if (!txQueue->isEmpty()) {
        networkInterface->setState(NetworkInterface::State::GOING_DOWN);
        delayActiveOperationFinish(par("stopOperationTimeout"));
    }
    else {
        networkInterface->setCarrier(false);
        networkInterface->setState(NetworkInterface::State::DOWN);
        startActiveOperationExtraTimeOrFinish(par("stopOperationExtraTime"));
    }
}

handleUpperPacket()

void inet::Ppp::handleUpperPacket ( Packet *  packet )

overrideprotectedvirtual

Reimplemented from inet::LayeredProtocolBase.

{
    EV_INFO << "Received " << packet << " from upper layer.\n";
    if (datarateChannel == nullptr) {
        EV_WARN << "Interface is not connected, dropping packet " << packet << endl;
        numDroppedIfaceDown++;
        PacketDropDetails details;
        details.setReason(INTERFACE_DOWN);
        emit(packetDroppedSignal, packet, &details);
        delete packet;
        return;
    }
    if (currentTxFrame != nullptr)
        throw cRuntimeError("PPP already in transmit state when packet arrived from upper layer");
    currentTxFrame = packet;
    startTransmitting();
}

Referenced by processUpperPacket().

initialize()

void inet::Ppp::initialize ( int  stage )

overrideprotectedvirtual

Reimplemented from inet::MacProtocolBase.

{
    MacProtocolBase::initialize(stage);
 
    // all initialization is done in the first stage
    if (stage == INITSTAGE_LOCAL) {
        displayStringTextFormat = par("displayStringTextFormat");
        sendRawBytes = par("sendRawBytes");
        endTransmissionEvent = new cMessage("pppEndTxEvent");
        lowerLayerInGateId = findGate("phys$i");
        physOutGate = gate("phys$o");
        lowerLayerOutGateId = physOutGate->getId();
 
        setTxUpdateSupport(true);
        // we're connected if other end of connection path is an input gate
        bool connected = physOutGate->getPathEndGate()->getType() == cGate::INPUT;
        // if we're connected, get the gate with transmission rate
        datarateChannel = connected ? physOutGate->getTransmissionChannel() : nullptr;
 
        numSent = numRcvdOK = numDroppedBitErr = numDroppedIfaceDown = 0;
        WATCH(numSent);
        WATCH(numRcvdOK);
        WATCH(numDroppedBitErr);
        WATCH(numDroppedIfaceDown);
 
        subscribe(PRE_MODEL_CHANGE, this);
        subscribe(POST_MODEL_CHANGE, this);
        emit(transmissionStateChangedSignal, 0L);
 
        txQueue = getQueue(gate(upperLayerInGateId));
    }
}

numInitStages()

virtual int inet::Ppp::numInitStages ( ) const

inlineoverrideprotectedvirtual

{ return NUM_INIT_STAGES; }

processUpperPacket()

void inet::Ppp::processUpperPacket ( )

protectedvirtual

{
    auto packet = dequeuePacket();
    handleUpperPacket(packet);
}

Referenced by handleCanPullPacketChanged(), handleSelfMessage(), and refreshOutGateConnection().

receiveSignal()

void inet::Ppp::receiveSignal ( cComponent *  source, simsignal_t  signalID, cObject *  obj, cObject *  details  )

overrideprotectedvirtual

Reimplemented from inet::MacProtocolBase.

{
    Enter_Method("%s", cComponent::getSignalName(signalID));
 
    MacProtocolBase::receiveSignal(source, signalID, obj, details);
 
    if (getSimulation()->getSimulationStage() == CTX_CLEANUP)
        return;
 
    if (signalID == POST_MODEL_CHANGE) {
        if (auto gcobj = dynamic_cast<cPostPathCreateNotification *>(obj)) {
            if (physOutGate == gcobj->pathStartGate)
                refreshOutGateConnection(true);
        }
        else if (auto gcobj = dynamic_cast<cPostPathCutNotification *>(obj)) {
            if (physOutGate == gcobj->pathStartGate)
                refreshOutGateConnection(false);
        }
        else if (datarateChannel && dynamic_cast<cPostParameterChangeNotification *>(obj)) {
            cPostParameterChangeNotification *gcobj = static_cast<cPostParameterChangeNotification *>(obj);
            if (datarateChannel == gcobj->par->getOwner() && !strcmp("datarate", gcobj->par->getName()))
                refreshOutGateConnection(true);
        }
    }
    else if (signalID == PRE_MODEL_CHANGE) {
        if (auto gcobj = dynamic_cast<cPrePathCutNotification *>(obj)) {
            if (physOutGate == gcobj->pathStartGate)
                refreshOutGateConnection(false);
        }
    }
}

refreshDisplay()

void inet::Ppp::refreshDisplay ( ) const

overrideprotectedvirtual

{
    MacProtocolBase::refreshDisplay();
 
    if (displayStringTextFormat != nullptr) {
        auto text = StringFormat::formatString(displayStringTextFormat, [&] (char directive) {
            static std::string result;
            switch (directive) {
                case 's':
                    result = std::to_string(numSent);
                    break;
                case 'r':
                    result = std::to_string(numRcvdOK);
                    break;
                case 'd':
                    result = std::to_string(numDroppedIfaceDown + numDroppedBitErr);
                    break;
                case 'q':
                    result = std::to_string(txQueue->getNumPackets());
                    break;
                case 'b':
                    if (datarateChannel == nullptr)
                        result = "not connected";
                    else {
                        char datarateText[40];
                        double datarate = datarateChannel->getNominalDatarate();
                        if (datarate >= 1e9)
                            sprintf(datarateText, "%gGbps", datarate / 1e9);
                        else if (datarate >= 1e6)
                            sprintf(datarateText, "%gMbps", datarate / 1e6);
                        else if (datarate >= 1e3)
                            sprintf(datarateText, "%gkbps", datarate / 1e3);
                        else
                            sprintf(datarateText, "%gbps", datarate);
                        result = datarateText;
                    }
                    break;
                default:
                    throw cRuntimeError("Unknown directive: %c", directive);
            }
            return result.c_str();
        });
        getDisplayString().setTagArg("t", 0, text);
    }
 
    const char *color = "";
    if (datarateChannel != nullptr) {
        if (endTransmissionEvent->isScheduled())
            color = txQueue->getNumPackets() >= 3 ? "red" : "yellow";
    }
    else
        color = "#707070";
    getDisplayString().setTagArg("i", 1, color);
}

refreshOutGateConnection()

void inet::Ppp::refreshOutGateConnection ( bool  connected )

protectedvirtual

{
    Enter_Method("refreshOutGateConnection");
 
    // we're connected if other end of connection path is an input gate
    if (connected)
        ASSERT(physOutGate->getPathEndGate()->getType() == cGate::INPUT);
 
    if (!connected) {
        if (endTransmissionEvent->isScheduled()) {
            ASSERT(curTxPacket != nullptr);
            simtime_t startTransmissionTime = endTransmissionEvent->getSendingTime();
            simtime_t sentDuration = simTime() - startTransmissionTime;
            double sentPart = sentDuration / (endTransmissionEvent->getArrivalTime() - startTransmissionTime);
            b newLength = b(floor(curTxPacket->getBitLength() * sentPart));
            curTxPacket->removeAtBack(curTxPacket->getDataLength() - newLength);
            curTxPacket->setBitError(true);
            send(curTxPacket, SendOptions().finishTx(curTxPacket->getId()).duration(sentDuration), physOutGate);
            curTxPacket = nullptr;
            cancelEvent(endTransmissionEvent);
        }
 
        PacketDropDetails details;
        details.setReason(INTERFACE_DOWN); // TODO choose a correct PacketDropReason value
        flushQueue(details);
    }
 
    cChannel *oldChannel = datarateChannel;
    // if we're connected, get the gate with transmission rate
    datarateChannel = connected ? physOutGate->getTransmissionChannel() : nullptr;
    double datarate = connected ? datarateChannel->getNominalDatarate() : 0;
 
    if (datarateChannel && !oldChannel)
        datarateChannel->subscribe(POST_MODEL_CHANGE, this);
 
    // update interface state if it is in use
    if (networkInterface) {
        networkInterface->setCarrier(connected);
        networkInterface->setDatarate(datarate);
    }
 
    if (connected && currentTxFrame == nullptr && canDequeuePacket()) {
        ASSERT(!endTransmissionEvent->isScheduled());
        processUpperPacket();
    }
}

Referenced by receiveSignal().

startTransmitting()

void inet::Ppp::startTransmitting ( )

protectedvirtual

{
    // if there's any control info, remove it; then encapsulate the packet
    Packet *pppFrame = currentTxFrame->dup();
    encapsulate(pppFrame);
 
    // send
    EV_INFO << "Transmission of " << pppFrame << " started.\n";
    emit(transmissionStateChangedSignal, 1L);
    emit(packetSentToLowerSignal, pppFrame);
    auto& oldPacketProtocolTag = pppFrame->removeTag<PacketProtocolTag>();
    pppFrame->clearTags();
    auto newPacketProtocolTag = pppFrame->addTag<PacketProtocolTag>();
    *newPacketProtocolTag = *oldPacketProtocolTag;
    if (sendRawBytes) {
        auto bytes = pppFrame->peekDataAsBytes();
        pppFrame->eraseAll();
        pppFrame->insertAtFront(bytes);
    }
    curTxPacket = pppFrame->dup();
    send(pppFrame, SendOptions().transmissionId(curTxPacket->getId()), physOutGate);
 
    ASSERT(datarateChannel == physOutGate->getTransmissionChannel()); // FIXME reread datarateChannel when changed
 
    // schedule an event for the time when last bit will leave the gate.
    simtime_t endTransmissionTime = datarateChannel->getTransmissionFinishTime();
    scheduleAt(endTransmissionTime, endTransmissionEvent);
    numSent++;
}

Referenced by handleUpperPacket().

Member Data Documentation

curTxPacket

Packet* inet::Ppp::curTxPacket = nullptr

protected

Referenced by handleSelfMessage(), refreshOutGateConnection(), startTransmitting(), and ~Ppp().

datarateChannel

cChannel* inet::Ppp::datarateChannel = nullptr

protected

Referenced by configureNetworkInterface(), handleUpperPacket(), initialize(), receiveSignal(), refreshDisplay(), refreshOutGateConnection(), and startTransmitting().

displayStringTextFormat

const char* inet::Ppp::displayStringTextFormat = nullptr

protected

Referenced by initialize(), and refreshDisplay().

endTransmissionEvent

cMessage* inet::Ppp::endTransmissionEvent = nullptr

protected

Referenced by handleSelfMessage(), initialize(), refreshDisplay(), refreshOutGateConnection(), startTransmitting(), and ~Ppp().

numDroppedBitErr

long inet::Ppp::numDroppedBitErr = 0

protected

Referenced by handleLowerPacket(), initialize(), and refreshDisplay().

numDroppedIfaceDown

long inet::Ppp::numDroppedIfaceDown = 0

protected

Referenced by handleUpperPacket(), initialize(), and refreshDisplay().

numRcvdOK

long inet::Ppp::numRcvdOK = 0

protected

Referenced by handleLowerPacket(), initialize(), and refreshDisplay().

numSent

long inet::Ppp::numSent = 0

protected

Referenced by initialize(), refreshDisplay(), and startTransmitting().

oldConnColor

std::string inet::Ppp::oldConnColor

protected

physOutGate

cGate* inet::Ppp::physOutGate = nullptr

protected

Referenced by initialize(), receiveSignal(), refreshOutGateConnection(), and startTransmitting().

rxPkOkSignal

simsignal_t inet::Ppp::rxPkOkSignal = registerSignal("rxPkOk")

staticprotected

Referenced by handleLowerPacket().

sendRawBytes

bool inet::Ppp::sendRawBytes = false

protected

Referenced by initialize(), and startTransmitting().

transmissionStateChangedSignal

simsignal_t inet::Ppp::transmissionStateChangedSignal = registerSignal("transmissionStateChanged")

staticprotected

Referenced by handleSelfMessage(), initialize(), and startTransmitting().

---

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

• Ppp.h
• Ppp.cc