daemon/src/routing/epidemic/EpidemicRoutingExtension.cpp

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/*
 * EpidemicRoutingExtension.cpp
 *
 *  Created on: 18.02.2010
 *      Author: morgenro
 */

#include "routing/epidemic/EpidemicRoutingExtension.h"
#include "routing/epidemic/EpidemicControlMessage.h"

#include "routing/QueueBundleEvent.h"
#include "net/TransferCompletedEvent.h"
#include "net/TransferAbortedEvent.h"
#include "core/BundleExpiredEvent.h"
#include "core/NodeEvent.h"
#include "core/TimeEvent.h"
#include "core/Node.h"
#include "net/ConnectionManager.h"
#include "Configuration.h"
#include "core/BundleCore.h"
#include "core/BundleGeneratedEvent.h"

#include <ibrdtn/data/MetaBundle.h>
#include <ibrcommon/thread/MutexLock.h>
#include <ibrcommon/Logger.h>
#include <ibrcommon/AutoDelete.h>

#include <functional>
#include <list>
#include <algorithm>

#include <iomanip>
#include <ios>
#include <iostream>
#include <set>

#include <stdlib.h>
#include <typeinfo>

namespace dtn
{
        namespace routing
        {
                EpidemicRoutingExtension::EpidemicRoutingExtension()
                {
                        // write something to the syslog
                        IBRCOMMON_LOGGER(info) << "Initializing epidemic routing module" << IBRCOMMON_LOGGER_ENDL;
                }

                EpidemicRoutingExtension::~EpidemicRoutingExtension()
                {
                        stop();
                        join();
                }

                void EpidemicRoutingExtension::stopExtension()
                {
                        _taskqueue.abort();
                }

                void EpidemicRoutingExtension::notify(const dtn::core::Event *evt)
                {
                        // If an incoming bundle is received, forward it to all connected neighbors
                        try {
                                const QueueBundleEvent &queued = dynamic_cast<const QueueBundleEvent&>(*evt);
                                _taskqueue.push( new ProcessBundleTask(queued.bundle, queued.origin) );
                                return;
                        } catch (const std::bad_cast&) { };

                        // On each time event look for expired stuff
                        try {
                                const dtn::core::TimeEvent &time = dynamic_cast<const dtn::core::TimeEvent&>(*evt);

                                if (time.getAction() == dtn::core::TIME_SECOND_TICK)
                                {
                                        // check all lists for expired entries
                                        _taskqueue.push( new ExpireTask(time.getTimestamp()) );
                                }
                                return;
                        } catch (const std::bad_cast&) { };

                        // If a new neighbor comes available, send him a request for the summary vector
                        // If a neighbor went away we can free the stored summary vector
                        try {
                                const dtn::core::NodeEvent &nodeevent = dynamic_cast<const dtn::core::NodeEvent&>(*evt);
                                const dtn::core::Node &n = nodeevent.getNode();

                                if (nodeevent.getAction() == NODE_AVAILABLE)
                                {
                                        NeighborDatabase &db = (**this).getNeighborDB();

                                        try {
                                                // lock the list of neighbors
                                                ibrcommon::MutexLock l(db);
                                                NeighborDatabase::NeighborEntry &entry = db.get(n.getEID());

                                                // acquire resources to send a summary vector request
                                                entry.acquireFilterRequest();

                                                // query a new summary vector from this neighbor
                                                _taskqueue.push( new QuerySummaryVectorTask( n.getEID() ) );
                                        } catch (const NeighborDatabase::NoMoreTransfersAvailable&) {
                                        } catch (const NeighborDatabase::NeighborNotAvailableException&) { };
                                }

                                return;
                        } catch (const std::bad_cast&) { };

                        // The bundle transfer has been aborted
                        try {
                                const dtn::net::TransferAbortedEvent &aborted = dynamic_cast<const dtn::net::TransferAbortedEvent&>(*evt);

                                // transfer the next bundle to this destination
                                _taskqueue.push( new SearchNextBundleTask( aborted.getPeer() ) );

                                return;
                        } catch (const std::bad_cast&) { };

                        // A bundle transfer was successful
                        try {
                                const dtn::net::TransferCompletedEvent &completed = dynamic_cast<const dtn::net::TransferCompletedEvent&>(*evt);

                                // create a transfer completed task
                                _taskqueue.push( new TransferCompletedTask( completed.getPeer(), completed.getBundle() ) );
                                return;
                        } catch (const std::bad_cast&) { };
                }

                bool EpidemicRoutingExtension::__cancellation()
                {
                        _taskqueue.abort();
                        return true;
                }

                void EpidemicRoutingExtension::run()
                {
                        class BundleFilter : public dtn::core::BundleStorage::BundleFilterCallback
                        {
                        public:
                                BundleFilter(const NeighborDatabase::NeighborEntry &entry)
                                 : _entry(entry)
                                {};

                                virtual ~BundleFilter() {};

                                virtual size_t limit() const { return 10; };

                                virtual bool shouldAdd(const dtn::data::MetaBundle &meta) const
                                {
                                        // do not forward any epidemic control message
                                        // this is done by the neighbor routing module
                                        if (meta.source == (dtn::core::BundleCore::local + "/routing/epidemic"))
                                        {
                                                return false;
                                        }

                                        // do not forward to any blacklisted destination
                                        const dtn::data::EID dest = meta.destination.getNodeEID();
                                        if (_blacklist.find(dest) != _blacklist.end())
                                        {
                                                return false;
                                        }

                                        // do not forward bundles already known by the destination
                                        // throws BloomfilterNotAvailableException if no filter is available or it is expired
                                        if (_entry.has(meta, true))
                                        {
                                                return false;
                                        }

                                        return true;
                                };

                                void blacklist(const dtn::data::EID& id)
                                {
                                        _blacklist.insert(id);
                                };

                        private:
                                std::set<dtn::data::EID> _blacklist;
                                const NeighborDatabase::NeighborEntry &_entry;
                        };

                        dtn::core::BundleStorage &storage = (**this).getStorage();

                        while (true)
                        {
                                try {
                                        Task *t = _taskqueue.getnpop(true);
                                        ibrcommon::AutoDelete<Task> killer(t);

                                        IBRCOMMON_LOGGER_DEBUG(50) << "processing epidemic task " << t->toString() << IBRCOMMON_LOGGER_ENDL;

                                        try {
                                                try {
                                                        ExecutableTask &etask = dynamic_cast<ExecutableTask&>(*t);
                                                        etask.execute();
                                                } catch (const std::bad_cast&) { };

                                                try {
                                                        ExpireTask &task = dynamic_cast<ExpireTask&>(*t);
                                                        _purge_vector.expire(task.timestamp);
                                                } catch (const std::bad_cast&) { };

                                                try {
                                                        SearchNextBundleTask &task = dynamic_cast<SearchNextBundleTask&>(*t);
                                                        NeighborDatabase &db = (**this).getNeighborDB();

                                                        ibrcommon::MutexLock l(db);
                                                        NeighborDatabase::NeighborEntry &entry = db.get(task.eid);

                                                        try {
                                                                // get the bundle filter of the neighbor
                                                                BundleFilter filter(entry);

                                                                // some debug output
                                                                IBRCOMMON_LOGGER_DEBUG(40) << "search some bundles not known by " << task.eid.getString() << IBRCOMMON_LOGGER_ENDL;

                                                                // blacklist the neighbor itself, because this is handled by neighbor routing extension
                                                                filter.blacklist(task.eid);

                                                                // query some unknown bundle from the storage, the list contains max. 10 items.
                                                                const std::list<dtn::data::MetaBundle> list = storage.get(filter);

                                                                // send the bundles as long as we have resources
                                                                for (std::list<dtn::data::MetaBundle>::const_iterator iter = list.begin(); iter != list.end(); iter++)
                                                                {
                                                                        try {
                                                                                // transfer the bundle to the neighbor
                                                                                transferTo(entry, *iter);
                                                                        } catch (const NeighborDatabase::AlreadyInTransitException&) { };
                                                                }
                                                        } catch (const NeighborDatabase::BloomfilterNotAvailableException&) {
                                                                // acquire resources to send a summary vector request
                                                                entry.acquireFilterRequest();

                                                                // query a new summary vector from this neighbor
                                                                _taskqueue.push( new QuerySummaryVectorTask( task.eid ) );
                                                        }
                                                } catch (const NeighborDatabase::NoMoreTransfersAvailable&) {
                                                } catch (const NeighborDatabase::NeighborNotAvailableException&) {
                                                } catch (const std::bad_cast&) { };

                                                try {
                                                        TransferCompletedTask &task = dynamic_cast<TransferCompletedTask&>(*t);

                                                        // add this bundle to the purge vector if it is delivered to its destination
                                                        if (( EID(task.peer.getNodeEID()) == EID(task.meta.destination.getNodeEID()) ) && (task.meta.procflags & dtn::data::Bundle::DESTINATION_IS_SINGLETON))
                                                        {
                                                                IBRCOMMON_LOGGER_DEBUG(15) << "singleton bundle delivered: " << task.meta.toString() << IBRCOMMON_LOGGER_ENDL;

                                                                // add it to the purge vector
                                                                _purge_vector.add(task.meta);
                                                        }

                                                        // transfer the next bundle to this destination
                                                        _taskqueue.push( new SearchNextBundleTask( task.peer ) );
                                                } catch (const std::bad_cast&) { };

                                                try {
                                                        ProcessBundleTask &task = dynamic_cast<ProcessBundleTask&>(*t);

                                                        // look for ECM bundles
                                                        if ( task.bundle.destination == (dtn::core::BundleCore::local + "/routing/epidemic") )
                                                        {
                                                                // the bundle is an control message, get it from the storage
                                                                dtn::data::Bundle bundle = storage.get(task.bundle);

                                                                // process the incoming ECM
                                                                processECM(task.origin, bundle);

                                                                // we do not need it anymore in the storage
                                                                storage.remove(bundle);
                                                        }
                                                        else
                                                        {
                                                                // new bundles trigger a recheck for all neighbors
                                                                const std::set<dtn::core::Node> nl = dtn::core::BundleCore::getInstance().getNeighbors();

                                                                for (std::set<dtn::core::Node>::const_iterator iter = nl.begin(); iter != nl.end(); iter++)
                                                                {
                                                                        const dtn::core::Node &n = (*iter);

                                                                        // transfer the next bundle to this destination
                                                                        _taskqueue.push( new SearchNextBundleTask( n.getEID() ) );
                                                                }
                                                        }
                                                } catch (const dtn::core::BundleStorage::NoBundleFoundException&) {
                                                        // if the bundle is not in the storage we have nothing to do
                                                } catch (const std::bad_cast&) { };
                                        } catch (const ibrcommon::Exception &ex) {
                                                IBRCOMMON_LOGGER_DEBUG(20) << "Exception occurred in EpidemicRoutingExtension: " << ex.what() << IBRCOMMON_LOGGER_ENDL;
                                        }
                                } catch (const std::exception&) {
                                        return;
                                }

                                yield();
                        }
                }

                /****************************************/

                EpidemicRoutingExtension::SearchNextBundleTask::SearchNextBundleTask(const dtn::data::EID &e)
                 : eid(e)
                { }

                EpidemicRoutingExtension::SearchNextBundleTask::~SearchNextBundleTask()
                { }

                std::string EpidemicRoutingExtension::SearchNextBundleTask::toString()
                {
                        return "SearchNextBundleTask: " + eid.getString();
                }

                /****************************************/

                EpidemicRoutingExtension::ProcessBundleTask::ProcessBundleTask(const dtn::data::MetaBundle &meta, const dtn::data::EID &o)
                 : bundle(meta), origin(o)
                { }

                EpidemicRoutingExtension::ProcessBundleTask::~ProcessBundleTask()
                { }

                std::string EpidemicRoutingExtension::ProcessBundleTask::toString()
                {
                        return "ProcessBundleTask: " + bundle.toString();
                }

                /****************************************/

                EpidemicRoutingExtension::ExpireTask::ExpireTask(const size_t t)
                 : timestamp(t)
                { }

                EpidemicRoutingExtension::ExpireTask::~ExpireTask()
                { }

                std::string EpidemicRoutingExtension::ExpireTask::toString()
                {
                        return "ExpireTask";
                }

                /****************************************/

                EpidemicRoutingExtension::TransferCompletedTask::TransferCompletedTask(const dtn::data::EID &e, const dtn::data::MetaBundle &m)
                 : peer(e), meta(m)
                { }

                EpidemicRoutingExtension::TransferCompletedTask::~TransferCompletedTask()
                { }

                std::string EpidemicRoutingExtension::TransferCompletedTask::toString()
                {
                        return "TransferCompletedTask";
                }

                /****************************************/

                EpidemicRoutingExtension::QuerySummaryVectorTask::QuerySummaryVectorTask(const dtn::data::EID &o)
                 : origin(o)
                { }

                EpidemicRoutingExtension::QuerySummaryVectorTask::~QuerySummaryVectorTask()
                { }

                void EpidemicRoutingExtension::QuerySummaryVectorTask::execute() const
                {
                        // create a new request for the summary vector of the neighbor
                        EpidemicControlMessage ecm;

                        // set message type
                        ecm.type = EpidemicControlMessage::ECM_QUERY_SUMMARY_VECTOR;

                        // create a new bundle
                        dtn::data::Bundle req;

                        // set the source of the bundle
                        req._source = dtn::core::BundleCore::local + "/routing/epidemic";

                        // set the destination of the bundle
                        req.set(dtn::data::PrimaryBlock::DESTINATION_IS_SINGLETON, true);
                        req._destination = origin + "/routing/epidemic";

                        // limit the lifetime to 60 seconds
                        req._lifetime = 60;

                        // set high priority
                        req.set(dtn::data::PrimaryBlock::PRIORITY_BIT1, true);
                        req.set(dtn::data::PrimaryBlock::PRIORITY_BIT2, true);

                        dtn::data::PayloadBlock &p = req.push_back<PayloadBlock>();
                        ibrcommon::BLOB::Reference ref = p.getBLOB();

                        // serialize the request into the payload
                        {
                                ibrcommon::BLOB::iostream ios = ref.iostream();
                                (*ios) << ecm;
                        }

                        // transfer the bundle to the neighbor
                        dtn::core::BundleGeneratedEvent::raise(req);
                }

                std::string EpidemicRoutingExtension::QuerySummaryVectorTask::toString()
                {
                        return "QuerySummaryVectorTask: " + origin.getString();
                }

                void EpidemicRoutingExtension::processECM(const dtn::data::EID &origin, const dtn::data::Bundle &bundle)
                {
                        // read the ecm
                        const dtn::data::PayloadBlock &p = bundle.getBlock<dtn::data::PayloadBlock>();
                        ibrcommon::BLOB::Reference ref = p.getBLOB();
                        EpidemicControlMessage ecm;

                        // locked within this region
                        {
                                ibrcommon::BLOB::iostream s = ref.iostream();
                                (*s) >> ecm;
                        }

                        // if this is a request answer with an summary vector
                        if (ecm.type == EpidemicControlMessage::ECM_QUERY_SUMMARY_VECTOR)
                        {
                                // create a new request for the summary vector of the neighbor
                                EpidemicControlMessage response_ecm;

                                // set message type
                                response_ecm.type = EpidemicControlMessage::ECM_RESPONSE;

                                // add own summary vector to the message
                                const SummaryVector vec = (**this).getSummaryVector();
                                response_ecm.setSummaryVector(vec);

                                // add own purge vector to the message
                                response_ecm.setPurgeVector(_purge_vector);

                                // create a new bundle
                                dtn::data::Bundle answer;

                                // set the source of the bundle
                                answer._source = dtn::core::BundleCore::local + "/routing/epidemic";

                                // set the destination of the bundle
                                answer.set(dtn::data::PrimaryBlock::DESTINATION_IS_SINGLETON, true);
                                answer._destination = bundle._source;

                                // limit the lifetime to 60 seconds
                                answer._lifetime = 60;

                                // set high priority
                                answer.set(dtn::data::PrimaryBlock::PRIORITY_BIT1, true);
                                answer.set(dtn::data::PrimaryBlock::PRIORITY_BIT2, true);

                                dtn::data::PayloadBlock &p = answer.push_back<PayloadBlock>();
                                ibrcommon::BLOB::Reference ref = p.getBLOB();

                                // serialize the request into the payload
                                {
                                        ibrcommon::BLOB::iostream ios = ref.iostream();
                                        (*ios) << response_ecm;
                                }

                                // transfer the bundle to the neighbor
                                dtn::core::BundleGeneratedEvent::raise(answer);
                        }
                        else if (ecm.type == EpidemicControlMessage::ECM_RESPONSE)
                        {
                                if (ecm.flags & EpidemicControlMessage::ECM_CONTAINS_SUMMARY_VECTOR)
                                {
                                        // get the summary vector (bloomfilter) of this ECM
                                        const ibrcommon::BloomFilter &filter = ecm.getSummaryVector().getBloomFilter();

                                        try {
                                                NeighborDatabase &db = (**this).getNeighborDB();
                                                ibrcommon::MutexLock l(db);
                                                NeighborDatabase::NeighborEntry &entry = db.get(bundle._source.getNodeEID());
                                                entry.update(filter, bundle._lifetime);

                                                // trigger the search-for-next-bundle procedure
                                                _taskqueue.push( new SearchNextBundleTask( origin ) );
                                        } catch (const NeighborDatabase::NeighborNotAvailableException&) { };
                                }

                                if (ecm.flags & EpidemicControlMessage::ECM_CONTAINS_PURGE_VECTOR)
                                {
                                        // get the purge vector (bloomfilter) of this ECM
                                        const ibrcommon::BloomFilter &purge = ecm.getPurgeVector().getBloomFilter();

                                        dtn::core::BundleStorage &storage = (**this).getStorage();

                                        try {
                                                while (true)
                                                {
                                                        // delete bundles in the purge vector
                                                        const dtn::data::MetaBundle meta = storage.remove(purge);

                                                        IBRCOMMON_LOGGER_DEBUG(15) << "bundle purged: " << meta.toString() << IBRCOMMON_LOGGER_ENDL;

                                                        // add this bundle to the own purge vector
                                                        _purge_vector.add(meta);
                                                }
                                        } catch (const dtn::core::BundleStorage::NoBundleFoundException&) { };
                                }
                        }
                }
        }
}