LayerIgmp.cpp

#include "Headers.h"
#include "LayerIgmp.h"

CLayerIgmp::CLayerIgmp(
    CSimHandler*    sim,
    CAddress        address,
    __uint32        numGroups,
    EIgmpType       type
    ) : CLayer(sim)
{
    this->address = address;
    this->numGroups = numGroups;
    this->type = type;

    // Local groups
    this->memberships = new CLayerIpMcastMembership[this->numGroups];

    // Remote groups
    this->groups = new CLayerIpMcastGroup[this->numGroups];

    // Delegates
    this->delegateRecv = new Delegate2<CLayerIgmp, void, __uint32, CPacketIp*>(this, &CLayerIgmp::Recv);
    this->delegateJoin = new Delegate2<CLayerIgmp, void, CAddress, __uint32>(this, &CLayerIgmp::Join);
    this->delegateLeave = new Delegate1<CLayerIgmp, void, CAddress>(this, &CLayerIgmp::Leave);

    // Events
    this->eventJoin = new Event3<void, __uint32, CAddress, CLayerIpMcastGroup*>();
    this->eventLeave = new Event3<void, __uint32, CAddress, CLayerIpMcastGroup*>();
    this->eventLocalJoin = new Event2<void, __uint32, CAddress>();
    this->eventLocalLeave = new Event2<void, __uint32, CAddress>();
    this->eventSend = new Event2<void, __uint32, CPacketIp*>();

    // Statistics
    this->statEntries = 0;
    this->statEntriesNum = 0;
    this->statEntriesLast = 0;
}

CLayerIgmp::~CLayerIgmp()
{
    delete[] this->memberships;
    delete[] this->groups;

    delete this->delegateRecv;
    delete this->delegateJoin;
    delete this->delegateLeave;

    delete this->eventJoin;
    delete this->eventLeave;
    
    delete this->eventLocalJoin;
    delete this->eventLocalLeave;

    delete this->eventSend;
}

void CLayerIgmp::Join(CAddress address, __uint32 entry)
{
    __uint32 group = address.MulticastGroup();
    assert(group < this->numGroups);

    // If the host is part of the multicast group, return
    if(this->memberships[group].State() == CLayerIpMcastMembership::MEMBER) return;

    // Send an unsolicited membership report to the IP multicast address of the group
    CPacketIgmp* packet = new CPacketIgmp(address, CPacketIgmp::PACKET_IGMP_MEMBERSHIP_REPORT);

    // Send the IGMP packet on the joined interface, group multicast address and TTL of 1
    this->Send(entry, address, 1, packet);
    
    // Set the group state to joined
    this->memberships[group].Join(entry);

    // Call event for membership change
    (*this->eventLocalJoin)(entry, address);
}

void CLayerIgmp::Leave(CAddress address)
{
    __uint32 group = address.MulticastGroup();
    assert(group < this->numGroups);

    // If the host is not part of the multicast group, return
    if(this->memberships[group].State() == CLayerIpMcastMembership::NON_MEMBER) return;

    // Send a membership leave to the all routers multicast address
    CPacketIgmp* packet = new CPacketIgmp(address, CPacketIgmp::PACKET_IGMP_LEAVE_GROUP);

    // Send the IGMP packet on the joined interface, all routers multicast address and TTL of 1
    this->Send(this->memberships[group].Entry(), ADDRESS_MCAST_ALL_ROUTERS, 1, packet);

    // Call event for membership change
    (*this->eventLocalLeave)(this->memberships[group].Entry(), address);

    // Set group state to leave
    this->memberships[group].Leave();
}

void CLayerIgmp::Recv(__uint32 entry, CPacketIp* packet)
{
    // Process only IGMP packet
    if(packet->Payload() == NULL) return;
    if(packet->Payload()->Type() != PACKET_TYPE_IGMP) return;

#ifdef LOG_LAYER
    printf("\n\tT = %7.3lf IGMP RECV local=%u bytes=%u src=%u dst=%u", this->sim->Time(), this->address, packet->Size(), packet->Src(), packet->Dst());
#endif

    switch(packet->Dst().Address())
    {
    case ADDRESS_MCAST_ALL_SYSTEMS: this->RecvIgmpAllSystems(entry, packet->Src(), packet->Dst(), type_cast<CPacketIgmp*>(packet->Payload())); break;
    case ADDRESS_MCAST_ALL_ROUTERS: this->RecvIgmpAllRouters(entry, packet->Src(), packet->Dst(), type_cast<CPacketIgmp*>(packet->Payload())); break;
    default: this->RecvIgmpOther(entry, packet->Src(), packet->Dst(), type_cast<CPacketIgmp*>(packet->Payload())); break;
    }
}

void CLayerIgmp::RecvIgmpAllSystems(__uint32 entry, CAddress src, CAddress dst, CPacketIgmp* packet)
{
    // Do nothing (current implementation does not process all systems IGMP packets)
}

void CLayerIgmp::RecvIgmpAllRouters(__uint32 entry, CAddress src, CAddress dst, CPacketIgmp* packet)
{
    // Process all routers IGMP packets if the IGMP type is router
    if(this->type != IGMP_ROUTER) return;

    switch(packet->IgmpType())
    {
    case CPacketIgmp::PACKET_IGMP_LEAVE_GROUP: this->RecvIgmpLeaveGroup(entry, src, dst, packet); break; // Leave group
    default:; // Do nothing
    }
}

void CLayerIgmp::RecvIgmpOther(__uint32 entry, CAddress src, CAddress dst, CPacketIgmp* packet)
{
    // Process only multicast addresses or unicast addressed to this host
    if((!dst.IsMulticast()) && (dst != this->address)) return;

    switch(packet->IgmpType())
    {
    case CPacketIgmp::PACKET_IGMP_MEMBERSHIP_REPORT: this->RecvIgmpJoinGroup(entry, src, dst, packet); break; // Join group
    default:; // Do nothing
    }
}

void CLayerIgmp::RecvIgmpJoinGroup(__uint32 entry, CAddress src, CAddress dst, CPacketIgmp* packet)
{
    // Join group (membership report)
    __uint32 group = dst.MulticastGroup();
    assert(group < this->numGroups);

    // Statistics
    this->statEntries += (this->sim->Time() - this->statEntriesLast) * this->statEntriesNum;
    this->statEntriesNum -= this->groups[group].Out()->size();

    // Add the interface to the group
    this->groups[group].Out()->insert(entry);

    // Statistics
    this->statEntriesNum += this->groups[group].Out()->size();
    this->statEntriesLast = this->sim->Time();

    // Call event for this group
    (*this->eventJoin)(entry, dst, &this->groups[group]);
}

void CLayerIgmp::RecvIgmpLeaveGroup(__uint32 entry, CAddress src, CAddress dst, CPacketIgmp* packet)
{
    // Leave group
    __uint32 group = packet->Group().MulticastGroup();
    assert(group < this->numGroups);

    // Statistics
    this->statEntries += (this->sim->Time() - this->statEntriesLast) * this->statEntriesNum;
    this->statEntriesNum -= this->groups[group].Out()->size();

    // Remove the interface from the group
    this->groups[group].Out()->erase(entry);

    // Statistics
    this->statEntriesNum += this->groups[group].Out()->size();
    this->statEntriesLast = this->sim->Time();

    // Call event for this group
    (*this->eventLeave)(entry, packet->Group(), &this->groups[group]);
}

void CLayerIgmp::Send(__uint32 entry, CAddress dst, __byte ttl, CPacket* payload)
{
    // Create a new IP packet
    CPacketIp* packet = new CPacketIp(this->address, dst, ttl, payload);

#ifdef LOG_LAYER
    printf("\n\tT = %7.3lf IGMP SEND local=%u bytes=%u src=%u dst=%u", this->sim->Time(), this->address, packet->Size(), packet->Src(), packet->Dst());
#endif

    // Send the packet to the lower layer
    (*this->eventSend)(entry, packet);
}

void CLayerIgmp::Finalize()
{
    this->statEntries += (this->sim->Time() - this->statEntriesLast) * this->statEntriesNum;
    this->statEntries /= this->sim->Time();
}