inet::NextHopRoutingTable Class Reference

A C++ interface to abstract the functionality of a routing table, regardless of address type. More...

#include <NextHopRoutingTable.h>

Inheritance diagram for inet::NextHopRoutingTable:

Public Member Functions
	NextHopRoutingTable ()
virtual	~NextHopRoutingTable ()
Miscellaneous functions
virtual bool	isForwardingEnabled () const override
	Forwarding on/off. More...
virtual bool	isAdminDistEnabled () const override
	Administrative distance on/off. More...
virtual bool	isMulticastForwardingEnabled () const override
	Multicast forwarding on/off. More...
virtual L3Address	getRouterIdAsGeneric () const override
	Returns routerId. More...
virtual bool	isLocalAddress (const L3Address &dest) const override
	Checks if the address is a local one, i.e. More...
virtual NetworkInterface *	getInterfaceByAddress (const L3Address &address) const override
	Returns an interface given by its address. More...
virtual void	routeChanged (NextHopRoute *entry, int fieldCode)
	To be called from route objects whenever a field changes. More...
Routing functions (query the route table)
virtual NextHopRoute *	findBestMatchingRoute (const L3Address &dest) const override
	The routing function. More...
virtual NetworkInterface *	getOutputInterfaceForDestination (const L3Address &dest) const override
	Convenience function based on findBestMatchingRoute(). More...
virtual L3Address	getNextHopForDestination (const L3Address &dest) const override
	Convenience function based on findBestMatchingRoute(). More...
Multicast routing functions
virtual bool	isLocalMulticastAddress (const L3Address &dest) const override
	Checks if the address is in one of the local multicast group address list. More...
virtual IMulticastRoute *	findBestMatchingMulticastRoute (const L3Address &origin, const L3Address &group) const override
	Returns route for a multicast origin and group. More...
Route table manipulation
virtual int	getNumRoutes () const override
	Returns the total number of unicast routes. More...
virtual IRoute *	getRoute (int k) const override
	Returns the kth route. More...
virtual IRoute *	getDefaultRoute () const override
	Finds and returns the default route, or nullptr if it doesn't exist. More...
virtual void	addRoute (IRoute *entry) override
	Adds a route to the routing table. More...
virtual IRoute *	removeRoute (IRoute *entry) override
	Removes the given route from the routing table, and returns it. More...
virtual bool	deleteRoute (IRoute *entry) override
	Deletes the given route from the routing table. More...
virtual int	getNumMulticastRoutes () const override
	Returns the total number of multicast routes. More...
virtual IMulticastRoute *	getMulticastRoute (int k) const override
	Returns the kth multicast route. More...
virtual void	addMulticastRoute (IMulticastRoute *entry) override
	Adds a multicast route to the routing table. More...
virtual IMulticastRoute *	removeMulticastRoute (IMulticastRoute *entry) override
	Removes the given route from the routing table, and returns it. More...
virtual bool	deleteMulticastRoute (IMulticastRoute *entry) override
	Deletes the given multicast route from the routing table. More...
virtual IRoute *	createRoute () override
virtual void	printRoutingTable () const override
	Prints routing table. More...
Public Member Functions inherited from inet::IRoutingTable
virtual	~IRoutingTable ()

Protected Member Functions
virtual int	numInitStages () const override
virtual void	initialize (int stage) override
virtual void	handleMessage (cMessage *) override
	Raises an error. More...
virtual void	receiveSignal (cComponent *source, simsignal_t signalID, cObject *obj, cObject *details) override
	Called by the signal handler whenever a change of a category occurs to which this client has subscribed. More...
virtual void	configureRouterId ()
virtual void	refreshDisplay () const override
virtual void	configureInterface (NetworkInterface *ie)
virtual void	configureLoopback ()
void	internalAddRoute (NextHopRoute *route)
NextHopRoute *	internalRemoveRoute (NextHopRoute *route)

Static Protected Member Functions
static bool	routeLessThan (const NextHopRoute *a, const NextHopRoute *b)

Private Types
typedef std::vector< NextHopRoute * >	RouteVector
typedef std::vector< NextHopMulticastRoute * >	MulticastRouteVector

Private Attributes
ModuleRefByPar< IInterfaceTable >	ift
L3Address	routerId
L3Address::AddressType	addressType = L3Address::NONE
bool	forwarding = false
bool	multicastForwarding = false
RouteVector	routes
MulticastRouteVector	multicastRoutes

Detailed Description

A C++ interface to abstract the functionality of a routing table, regardless of address type.

Member Typedef Documentation

MulticastRouteVector

typedef std::vector<NextHopMulticastRoute *> inet::NextHopRoutingTable::MulticastRouteVector

private

RouteVector

typedef std::vector<NextHopRoute *> inet::NextHopRoutingTable::RouteVector

private

Constructor & Destructor Documentation

NextHopRoutingTable()

inet::NextHopRoutingTable::NextHopRoutingTable

(

)

{
}

~NextHopRoutingTable()

inet::NextHopRoutingTable::~NextHopRoutingTable ( )

virtual

{
    for (auto& elem : routes)
        delete elem;
    for (auto& elem : multicastRoutes)
        delete elem;
}

Member Function Documentation

addMulticastRoute()

void inet::NextHopRoutingTable::addMulticastRoute ( IMulticastRoute *  entry )

overridevirtual

Adds a multicast route to the routing table.

Routes are allowed to be modified while in the routing table. (There is a notification mechanism that allows routing table internals to be updated on a routing entry change.)

Implements inet::IRoutingTable.

{
    Enter_Method("addMulticastRoute(...)");
 
    // TODO
}

addRoute()

void inet::NextHopRoutingTable::addRoute ( IRoute *  entry )

overridevirtual

Adds a route to the routing table.

Routes are allowed to be modified while in the routing table. (There is a notification mechanism that allows routing table internals to be updated on a routing entry change.)

Implements inet::IRoutingTable.

{
    Enter_Method("addRoute(...)");
 
    NextHopRoute *entry = check_and_cast<NextHopRoute *>(route);
 
    // check that the interface exists
    if (!entry->getInterface())
        throw cRuntimeError("addRoute(): interface cannot be nullptr");
 
    internalAddRoute(entry);
 
    emit(routeAddedSignal, entry);
}

Referenced by inet::NextHopNetworkConfigurator::addStaticRoutes().

configureInterface()

void inet::NextHopRoutingTable::configureInterface ( NetworkInterface *  ie )

protectedvirtual

{
    int metric = (int)(ceil(2e9 / ie->getDatarate())); // use OSPF cost as default
    int interfaceModuleId = ie->getId();
    // mac
    auto d = ie->addProtocolData<NextHopInterfaceData>();
    d->setMetric(metric);
    if (addressType == L3Address::MAC)
        d->setAddress(ie->getMacAddress());
    else if (ie && addressType == L3Address::MODULEPATH)
        d->setAddress(ModulePathAddress(interfaceModuleId));
    else if (ie && addressType == L3Address::MODULEID)
        d->setAddress(ModuleIdAddress(interfaceModuleId));
}

Referenced by initialize().

configureLoopback()

void inet::NextHopRoutingTable::configureLoopback ( )

protectedvirtual

{
//TODO needed???
//    NetworkInterface *ie = ift->getFirstLoopbackInterface()
//    // add Ipv4 info. Set 127.0.0.1/8 as address by default --
//    // we may reconfigure later it to be the routerId
//    Ipv4InterfaceData *d = new Ipv4InterfaceData();
//    d->setIPAddress(Ipv4Address::LOOPBACK_ADDRESS);
//    d->setNetmask(Ipv4Address::LOOPBACK_NETMASK);
//    d->setMetric(1);
//    ie->setIPv4Data(d);
}

Referenced by initialize().

configureRouterId()

void inet::NextHopRoutingTable::configureRouterId ( )

protectedvirtual

{
    if (routerId.isUnspecified()) { // not yet configured
        const char *routerIdStr = par("routerId");
        if (!strcmp(routerIdStr, "auto")) { // non-"auto" cases already handled in earlier stage
            // choose highest interface address as routerId
            for (int i = 0; i < ift->getNumInterfaces(); ++i) {
                NetworkInterface *ie = ift->getInterface(i);
                if (!ie->isLoopback()) {
                    L3Address interfaceAddr = ie->getProtocolData<NextHopInterfaceData>()->getAddress();
                    if (routerId.isUnspecified() || routerId < interfaceAddr)
                        routerId = interfaceAddr;
                }
            }
        }
    }
//    else // already configured
//    {
//        // if there is no interface with routerId yet, assign it to the loopback address;
//        // TODO find out if this is a good practice, in which situations it is useful etc.
//        if (getInterfaceByAddress(routerId)==nullptr)
//        {
//            NetworkInterface *lo0 = ift->getFirstLoopbackInterface();
//            lo0->getNextHopProtocolData()->setAddress(routerId);
//        }
//    }
}

Referenced by initialize().

createRoute()

IRoute * inet::NextHopRoutingTable::createRoute ( )

overridevirtual

Implements inet::IRoutingTable.

{
    return new NextHopRoute();
}

deleteMulticastRoute()

bool inet::NextHopRoutingTable::deleteMulticastRoute ( IMulticastRoute *  entry )

overridevirtual

Deletes the given multicast route from the routing table.

Returns true if the route was deleted, and false if it was not in the routing table.

Implements inet::IRoutingTable.

{
    Enter_Method("deleteMulticastRoute(...)");
 
    return false; // TODO
}

deleteRoute()

bool inet::NextHopRoutingTable::deleteRoute ( IRoute *  entry )

overridevirtual

Deletes the given route from the routing table.

Returns true if the route was deleted, and false if it was not in the routing table.

Implements inet::IRoutingTable.

{
    Enter_Method("deleteRoute(...)");
 
    NextHopRoute *entry = internalRemoveRoute(check_and_cast<NextHopRoute *>(route));
    if (entry != nullptr) {
        EV_INFO << "remove route " << entry->str() << "\n";
        emit(routeDeletedSignal, entry);
        delete entry;
    }
    return entry != nullptr;
}

findBestMatchingMulticastRoute()

IMulticastRoute * inet::NextHopRoutingTable::findBestMatchingMulticastRoute ( const L3Address &  origin, const L3Address &  group  ) const

overridevirtual

Returns route for a multicast origin and group.

Implements inet::IRoutingTable.

{
    Enter_Method("findBestMatchingMulticastRoute(%s, %s)", origin.str().c_str(), group.str().c_str());
 
    return nullptr; // TODO
}

findBestMatchingRoute()

NextHopRoute * inet::NextHopRoutingTable::findBestMatchingRoute ( const L3Address &  dest ) const

overridevirtual

The routing function.

Performs longest prefix match for the given destination address, and returns the resulting route. Returns nullptr if there is no matching route.

Implements inet::IRoutingTable.

{
    Enter_Method("findBestMatchingRoute(%s)", dest.str().c_str());
 
    // find best match (one with longest prefix)
    // default route has zero prefix length, so (if exists) it'll be selected as last resort
    NextHopRoute *bestRoute = nullptr;
    for (auto e : routes) {
 
        if (dest.matches(e->getDestinationAsGeneric(), e->getPrefixLength())) {
            bestRoute = const_cast<NextHopRoute *>(e);
            break;
        }
    }
    return bestRoute;
}

Referenced by getNextHopForDestination(), and getOutputInterfaceForDestination().

getDefaultRoute()

IRoute * inet::NextHopRoutingTable::getDefaultRoute ( ) const

overridevirtual

Finds and returns the default route, or nullptr if it doesn't exist.

Implements inet::IRoutingTable.

{
    // if there is a default route entry, it is the last valid entry
    auto i = routes.rbegin();
    if (i != routes.rend() && (*i)->getPrefixLength() == 0)
        return *i;
    return nullptr;
}

getInterfaceByAddress()

NetworkInterface * inet::NextHopRoutingTable::getInterfaceByAddress ( const L3Address &  address ) const

overridevirtual

Returns an interface given by its address.

Returns nullptr if not found.

Implements inet::IRoutingTable.

{
    Enter_Method("getInterfaceByAddress(%s)", address.str().c_str());
 
    return ift->findInterfaceByAddress(address);
}

getMulticastRoute()

IMulticastRoute * inet::NextHopRoutingTable::getMulticastRoute ( int  k ) const

overridevirtual

Returns the kth multicast route.

Implements inet::IRoutingTable.

{
    return nullptr; // TODO
}

getNextHopForDestination()

L3Address inet::NextHopRoutingTable::getNextHopForDestination ( const L3Address &  dest ) const

overridevirtual

Convenience function based on findBestMatchingRoute().

Returns the gateway for the destination address. Returns the unspecified address if the destination is not in routing table or the gateway field is not filled in in the route.

Implements inet::IRoutingTable.

{
    Enter_Method("getGatewayForDestAddr(%s)", dest.str().c_str());
 
    const IRoute *e = findBestMatchingRoute(dest);
    return e ? e->getNextHopAsGeneric() : L3Address();
}

getNumMulticastRoutes()

int inet::NextHopRoutingTable::getNumMulticastRoutes ( ) const

overridevirtual

Returns the total number of multicast routes.

Implements inet::IRoutingTable.

{
    return 0; // TODO
}

getNumRoutes()

int inet::NextHopRoutingTable::getNumRoutes ( ) const

overridevirtual

Returns the total number of unicast routes.

Implements inet::IRoutingTable.

{
    return routes.size();
}

getOutputInterfaceForDestination()

NetworkInterface * inet::NextHopRoutingTable::getOutputInterfaceForDestination ( const L3Address &  dest ) const

overridevirtual

Convenience function based on findBestMatchingRoute().

Returns the output interface for the packets with dest as destination address, or nullptr if the destination is not in routing table.

Implements inet::IRoutingTable.

{
    Enter_Method("getInterfaceForDestAddr(%s)", dest.str().c_str());
 
    const IRoute *e = findBestMatchingRoute(dest);
    return e ? e->getInterface() : nullptr;
}

getRoute()

IRoute * inet::NextHopRoutingTable::getRoute ( int  k ) const

overridevirtual

Returns the kth route.

Implements inet::IRoutingTable.

{
    ASSERT(k >= 0 && (unsigned int)k < routes.size());
    return routes[k];
}

getRouterIdAsGeneric()

L3Address inet::NextHopRoutingTable::getRouterIdAsGeneric ( ) const

overridevirtual

Returns routerId.

Implements inet::IRoutingTable.

{
    return routerId;
}

handleMessage()

void inet::NextHopRoutingTable::handleMessage ( cMessage *  msg )

overrideprotectedvirtual

Raises an error.

{
    throw cRuntimeError("This module doesn't process messages");
}

initialize()

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

overrideprotectedvirtual

{
    cSimpleModule::initialize(stage);
 
    if (stage == INITSTAGE_LOCAL) {
        // get a pointer to the IInterfaceTable
        ift.reference(this, "interfaceTableModule", true);
 
        const char *addressTypeString = par("addressType");
        if (!strcmp(addressTypeString, "mac"))
            addressType = L3Address::MAC;
        else if (!strcmp(addressTypeString, "modulepath"))
            addressType = L3Address::MODULEPATH;
        else if (!strcmp(addressTypeString, "moduleid"))
            addressType = L3Address::MODULEID;
        else
            throw cRuntimeError("Unknown address type");
        forwarding = par("forwarding");
        multicastForwarding = par("multicastForwarding");
 
        WATCH_PTRVECTOR(routes);
        WATCH_PTRVECTOR(multicastRoutes);
        WATCH(forwarding);
        WATCH(multicastForwarding);
        WATCH(routerId);
 
        cModule *host = getContainingNode(this);
        host->subscribe(interfaceCreatedSignal, this);
        host->subscribe(interfaceDeletedSignal, this);
        host->subscribe(interfaceStateChangedSignal, this);
        host->subscribe(interfaceConfigChangedSignal, this);
        host->subscribe(interfaceIpv4ConfigChangedSignal, this);
    }
    // TODO INITSTAGE
    else if (stage == INITSTAGE_LINK_LAYER) {
        // At this point, all L2 modules have registered themselves (added their
        // interface entries). Create the per-interface Ipv4 data structures.
        IInterfaceTable *interfaceTable = getModuleFromPar<IInterfaceTable>(par("interfaceTableModule"), this);
        for (int i = 0; i < interfaceTable->getNumInterfaces(); ++i)
            configureInterface(interfaceTable->getInterface(i));
    }
    else if (stage == INITSTAGE_NETWORK_LAYER) {
        configureLoopback();
 
        // read routing table file (and interface configuration)
//        RoutingTableParser parser(ift, this);
//        if (*filename && parser.readRoutingTableFromFile(filename)==-1)
//            throw cRuntimeError("Error reading routing table file %s", filename);
 
        // TODO
        // set routerId if param is not "" (==no routerId) or "auto" (in which case we'll
        // do it later in a later stage, after network configurators configured the interfaces)
//        const char *routerIdStr = par("routerId");
//        if (strcmp(routerIdStr, "") && strcmp(routerIdStr, "auto"))
//            routerId = Ipv4Address(routerIdStr);
        // routerID selection must be after network autoconfiguration assigned interface addresses
        configureRouterId();
 
        // we don't use notifications during initialize(), so we do it manually.
//        updateNetmaskRoutes();
 
//        printRoutingTable();
    }
}

internalAddRoute()

void inet::NextHopRoutingTable::internalAddRoute ( NextHopRoute *  route )

protected

{
    ASSERT(route->getRoutingTableAsGeneric() == nullptr);
 
    // add to tables
    // we keep entries sorted, so that we can stop at the first match when doing the longest prefix matching
    auto pos = upper_bound(routes.begin(), routes.end(), route, routeLessThan);
    routes.insert(pos, route);
 
    route->setRoutingTable(this);
}

Referenced by addRoute(), and routeChanged().

internalRemoveRoute()

NextHopRoute * inet::NextHopRoutingTable::internalRemoveRoute ( NextHopRoute *  route )

protected

{
    auto i = find(routes, route);
    if (i != routes.end()) {
        ASSERT(route->getRoutingTableAsGeneric() == this);
        routes.erase(i);
        return route;
    }
    return nullptr;
}

Referenced by deleteRoute(), removeRoute(), and routeChanged().

isAdminDistEnabled()

virtual bool inet::NextHopRoutingTable::isAdminDistEnabled ( ) const

inlineoverridevirtual

Administrative distance on/off.

Implements inet::IRoutingTable.

{ return false; }

isForwardingEnabled()

bool inet::NextHopRoutingTable::isForwardingEnabled ( ) const

overridevirtual

Forwarding on/off.

Implements inet::IRoutingTable.

{
    return forwarding;
}

isLocalAddress()

bool inet::NextHopRoutingTable::isLocalAddress ( const L3Address &  dest ) const

overridevirtual

Checks if the address is a local one, i.e.

one of the host's.

Implements inet::IRoutingTable.

{
    Enter_Method("isLocalAddress(%s)", dest.str().c_str());
 
    return ift->isLocalAddress(dest);
}

isLocalMulticastAddress()

bool inet::NextHopRoutingTable::isLocalMulticastAddress ( const L3Address &  dest ) const

overridevirtual

Checks if the address is in one of the local multicast group address list.

Implements inet::IRoutingTable.

{
    Enter_Method("isLocalMulticastAddress(%s)", dest.str().c_str());
 
    return dest.isMulticast(); // TODO
}

isMulticastForwardingEnabled()

bool inet::NextHopRoutingTable::isMulticastForwardingEnabled ( ) const

overridevirtual

Multicast forwarding on/off.

Implements inet::IRoutingTable.

{
    return multicastForwarding;
}

numInitStages()

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

inlineoverrideprotectedvirtual

{ return NUM_INIT_STAGES; }

printRoutingTable()

void inet::NextHopRoutingTable::printRoutingTable ( ) const

overridevirtual

Prints routing table.

Implements inet::IRoutingTable.

{
    for (const auto& elem : routes)
        EV_INFO << (elem)->getInterface()->getInterfaceFullPath() << " -> " << (elem)->getDestinationAsGeneric().str() << " as " << (elem)->str() << endl;
}

receiveSignal()

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

overrideprotectedvirtual

Called by the signal handler whenever a change of a category occurs to which this client has subscribed.

{
    Enter_Method("%s", cComponent::getSignalName(signalID));
 
    // TODO
}

refreshDisplay()

void inet::NextHopRoutingTable::refreshDisplay ( ) const

overrideprotectedvirtual

{
// TODO
//    char buf[80];
//    if (routerId.isUnspecified())
//        sprintf(buf, "%d+%d routes", (int)routes.size(), (int)multicastRoutes.size());
//    else
//        sprintf(buf, "routerId: %s\n%d+%d routes", routerId.str().c_str(), (int)routes.size(), (int)multicastRoutes.size());
//    getDisplayString().setTagArg("t", 0, buf);
}

removeMulticastRoute()

IMulticastRoute * inet::NextHopRoutingTable::removeMulticastRoute ( IMulticastRoute *  entry )

overridevirtual

Removes the given route from the routing table, and returns it.

nullptr is returned of the route was not in the routing table.

Implements inet::IRoutingTable.

{
    Enter_Method("removeMulticastRoute(...)");
 
    return nullptr; // TODO
}

removeRoute()

IRoute * inet::NextHopRoutingTable::removeRoute ( IRoute *  entry )

overridevirtual

Removes the given route from the routing table, and returns it.

nullptr is returned if the route was not in the routing table.

Implements inet::IRoutingTable.

{
    Enter_Method("removeRoute(...)");
 
    NextHopRoute *entry = internalRemoveRoute(check_and_cast<NextHopRoute *>(route));
    if (entry != nullptr) {
        EV_INFO << "remove route " << entry->str() << "\n";
        emit(routeDeletedSignal, entry);
        entry->setRoutingTable(nullptr);
    }
 
    return entry;
}

routeChanged()

void inet::NextHopRoutingTable::routeChanged ( NextHopRoute *  entry, int  fieldCode  )

virtual

To be called from route objects whenever a field changes.

Used for maintaining internal data structures and firing "routing table changed" notifications.

{
    if (fieldCode == IRoute::F_DESTINATION || fieldCode == IRoute::F_PREFIX_LENGTH || fieldCode == IRoute::F_METRIC) { // our data structures depend on these fields
        entry = internalRemoveRoute(entry);
        ASSERT(entry != nullptr); // failure means inconsistency: route was not found in this routing table
        internalAddRoute(entry);
 
//        invalidateCache();
    }
    emit(routeChangedSignal, entry); // TODO include fieldCode in the notification
}

Referenced by inet::NextHopRoute::changed().

routeLessThan()

bool inet::NextHopRoutingTable::routeLessThan ( const NextHopRoute *  a, const NextHopRoute *  b  )

staticprotected

{
    // helper for sort() in addRoute(). We want routes with longer
    // prefixes to be at front, so we compare them as "less".
    // For metric, a smaller value is better (we report that as "less").
    if (a->getPrefixLength() != b->getPrefixLength())
        return a->getPrefixLength() > b->getPrefixLength();
 
    if (a->getDestinationAsGeneric() != b->getDestinationAsGeneric())
        return a->getDestinationAsGeneric() < b->getDestinationAsGeneric();
 
    return a->getMetric() < b->getMetric();
}

Referenced by internalAddRoute().

Member Data Documentation

addressType

L3Address::AddressType inet::NextHopRoutingTable::addressType = L3Address::NONE

private

Referenced by configureInterface(), and initialize().

forwarding

bool inet::NextHopRoutingTable::forwarding = false

private

Referenced by initialize(), and isForwardingEnabled().

ift

ModuleRefByPar<IInterfaceTable> inet::NextHopRoutingTable::ift

private

Referenced by configureRouterId(), getInterfaceByAddress(), initialize(), and isLocalAddress().

multicastForwarding

bool inet::NextHopRoutingTable::multicastForwarding = false

private

Referenced by initialize(), and isMulticastForwardingEnabled().

multicastRoutes

MulticastRouteVector inet::NextHopRoutingTable::multicastRoutes

private

Referenced by initialize(), and ~NextHopRoutingTable().

routerId

L3Address inet::NextHopRoutingTable::routerId

private

Referenced by configureRouterId(), getRouterIdAsGeneric(), and initialize().

routes

RouteVector inet::NextHopRoutingTable::routes

private

Referenced by findBestMatchingRoute(), getDefaultRoute(), getNumRoutes(), getRoute(), initialize(), internalAddRoute(), internalRemoveRoute(), printRoutingTable(), and ~NextHopRoutingTable().

---

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

• NextHopRoutingTable.h
• NextHopRoutingTable.cc