daemon/src/net/TCPConnection.cpp

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/*
 * TCPConnection.cpp
 *
 *  Created on: 26.04.2010
 *      Author: morgenro
 */

#include "config.h"
#include "Configuration.h"
#include "core/BundleCore.h"
#include "core/BundleEvent.h"
#include "core/BundleStorage.h"

#include "net/TCPConvergenceLayer.h"
#include "net/BundleReceivedEvent.h"
#include "net/ConnectionEvent.h"
#include "net/TransferCompletedEvent.h"
#include "net/TransferAbortedEvent.h"
#include "routing/RequeueBundleEvent.h"

#include <ibrdtn/data/ScopeControlHopLimitBlock.h>
#include <ibrcommon/net/tcpclient.h>
#include <ibrcommon/TimeMeasurement.h>
#include <ibrcommon/net/vinterface.h>
#include <ibrcommon/Logger.h>

#include <iostream>
#include <iomanip>

#ifdef WITH_TLS
#include <openssl/x509.h>
#include "security/SecurityCertificateManager.h"
#include <ibrcommon/TLSExceptions.h>
#endif

#ifdef WITH_BUNDLE_SECURITY
#include "security/SecurityManager.h"
#endif

namespace dtn
{
        namespace net
        {
                /*
                 * class TCPConnection
                 */
                TCPConnection::TCPConnection(TCPConvergenceLayer & tcpsrv, ibrcommon::tcpstream *stream, const dtn::data::EID & name, const size_t timeout)
#ifdef WITH_TLS
                 : _peer(), _node(name), _tcpstream(stream), _tlsstream(stream), _stream(*this, _tlsstream, dtn::daemon::Configuration::getInstance().getNetwork().getTCPChunkSize()),
                   _sender(*this, _keepalive_timeout), _name(name), _timeout(timeout), _lastack(0), _keepalive_timeout(0), _callback(tcpsrv), _flags(0)
#else
                 : _peer(), _node(name), _tcpstream(stream), _stream(*this, *_tcpstream, dtn::daemon::Configuration::getInstance().getNetwork().getTCPChunkSize()),
                   _sender(*this, _keepalive_timeout), _name(name), _timeout(timeout), _lastack(0), _keepalive_timeout(0), _callback(tcpsrv), _flags(0)
#endif
                {
                        _stream.exceptions(std::ios::badbit | std::ios::eofbit);

                        if ( dtn::daemon::Configuration::getInstance().getNetwork().getTCPOptionNoDelay() )
                        {
                                stream->enableNoDelay();
                        }

                        // add default TCP connection
                        _node.clear();
                        _node.add( dtn::core::Node::URI(Node::NODE_CONNECTED, Node::CONN_TCPIP, "0.0.0.0") );

                        _flags |= dtn::streams::StreamContactHeader::REQUEST_ACKNOWLEDGMENTS;
                        _flags |= dtn::streams::StreamContactHeader::REQUEST_NEGATIVE_ACKNOWLEDGMENTS;

#ifdef WITH_TLS
                        // set tls mode to server
                        _tlsstream.setServer(true);
#endif
                }

                TCPConnection::TCPConnection(TCPConvergenceLayer &tcpsrv, const dtn::core::Node &node, const dtn::data::EID &name, const size_t timeout)
#ifdef WITH_TLS
                 : _peer(), _node(node), _tcpstream(new ibrcommon::tcpclient()), _tlsstream(_tcpstream.get()), _stream(*this, _tlsstream, dtn::daemon::Configuration::getInstance().getNetwork().getTCPChunkSize()),
                   _sender(*this, _keepalive_timeout), _name(name), _timeout(timeout), _lastack(0), _keepalive_timeout(0), _callback(tcpsrv), _flags(0)
#else
                 : _peer(), _node(node), _tcpstream(new ibrcommon::tcpclient()), _stream(*this, *_tcpstream, dtn::daemon::Configuration::getInstance().getNetwork().getTCPChunkSize()),
                   _sender(*this, _keepalive_timeout), _name(name), _timeout(timeout), _lastack(0), _keepalive_timeout(0), _callback(tcpsrv), _flags(0)
#endif
                {
                        _stream.exceptions(std::ios::badbit | std::ios::eofbit);

                        _flags |= dtn::streams::StreamContactHeader::REQUEST_ACKNOWLEDGMENTS;
                        _flags |= dtn::streams::StreamContactHeader::REQUEST_NEGATIVE_ACKNOWLEDGMENTS;
                }

                TCPConnection::~TCPConnection()
                {
                        // wait until the sender thread is finished
                        _sender.join();
                }

                void TCPConnection::queue(const dtn::data::BundleID &bundle)
                {
                        _sender.push(bundle);
                }

                const StreamContactHeader& TCPConnection::getHeader() const
                {
                        return _peer;
                }

                const dtn::core::Node& TCPConnection::getNode() const
                {
                        return _node;
                }

                void TCPConnection::rejectTransmission()
                {
                        _stream.reject();
                }

                void TCPConnection::eventShutdown(StreamConnection::ConnectionShutdownCases)
                {
                }

                void TCPConnection::eventTimeout()
                {
                        // event
                        ConnectionEvent::raise(ConnectionEvent::CONNECTION_TIMEOUT, _node);

                        // stop the receiver thread
                        this->stop();
                }

                void TCPConnection::eventError()
                {
                }

                void TCPConnection::eventConnectionUp(const StreamContactHeader &header)
                {
                        _peer = header;

                        // copy old attributes and urls to the new node object
                        Node n_old = _node;
                        _node = Node(header._localeid);
                        _node += n_old;

                        _keepalive_timeout = header._keepalive * 1000;

#ifdef WITH_TLS
                        /* if both nodes support TLS, activate it */
                        if((_peer._flags & dtn::streams::StreamContactHeader::REQUEST_TLS)
                                        && (_flags & dtn::streams::StreamContactHeader::REQUEST_TLS)){
                                try{
                                        X509 *peer_cert = _tlsstream.activate();
                                        if(!dtn::security::SecurityCertificateManager::validateSubject(peer_cert, _peer.getEID())){
                                                IBRCOMMON_LOGGER(warning) << "TCPConnection: certificate does not fit the EID." << IBRCOMMON_LOGGER_ENDL;
                                                throw ibrcommon::TLSCertificateVerificationException("certificate does not fit the EID");
                                        }
                                } catch(...){
                                        if(dtn::daemon::Configuration::getInstance().getSecurity().TLSRequired()){
                                                /* close the connection */
                                                IBRCOMMON_LOGGER(warning) << "TCPConnection: TLS failed, closing the connection." << IBRCOMMON_LOGGER_ENDL;
                                                throw;
                                        } else {
                                                IBRCOMMON_LOGGER(warning) << "TCPConnection: TLS failed, continuing unauthenticated." << IBRCOMMON_LOGGER_ENDL;
                                        }
                                }
                        } else {
                                /* TLS not supported by both Nodes, check if its required */
                                if(dtn::daemon::Configuration::getInstance().getSecurity().TLSRequired()){
                                        /* close the connection */
                                        IBRCOMMON_LOGGER(warning) << "TCPConnection: TLS not supported by both Peers. Closing the connection." << IBRCOMMON_LOGGER_ENDL;
                                        throw ibrcommon::TLSException("TLS not supported by peer.");
                                } else if(_flags & dtn::streams::StreamContactHeader::REQUEST_TLS){
                                        IBRCOMMON_LOGGER(warning) << "TCPConnection: TLS not supported by peer. Continuing without TLS." << IBRCOMMON_LOGGER_ENDL;
                                }
                                /* else: this node does not support TLS, should have already printed a warning */
                        }
#endif

                        // set the incoming timer if set (> 0)
                        if (_peer._keepalive > 0)
                        {
                                // set the timer
                                _tcpstream->setTimeout(header._keepalive * 2);
                        }

                        // raise up event
                        ConnectionEvent::raise(ConnectionEvent::CONNECTION_UP, _node);
                }

                void TCPConnection::eventConnectionDown()
                {
                        IBRCOMMON_LOGGER_DEBUG(40) << "TCPConnection::eventConnectionDown()" << IBRCOMMON_LOGGER_ENDL;

                        try {
                                // stop the sender
                                _sender.stop();
                        } catch (const ibrcommon::ThreadException &ex) {
                                IBRCOMMON_LOGGER_DEBUG(50) << "TCPConnection::eventConnectionDown(): ThreadException (" << ex.what() << ")" << IBRCOMMON_LOGGER_ENDL;
                        }

                        if (_peer._localeid != dtn::data::EID())
                        {
                                // event
                                ConnectionEvent::raise(ConnectionEvent::CONNECTION_DOWN, _node);
                        }
                }

                void TCPConnection::eventBundleRefused()
                {
                        try {
                                const dtn::data::BundleID bundle = _sentqueue.getnpop();

                                // requeue the bundle
                                TransferAbortedEvent::raise(EID(_node.getEID()), bundle, dtn::net::TransferAbortedEvent::REASON_REFUSED);

                                // set ACK to zero
                                _lastack = 0;

                        } catch (const ibrcommon::QueueUnblockedException&) {
                                // pop on empty queue!
                                IBRCOMMON_LOGGER(error) << "transfer refused without a bundle in queue" << IBRCOMMON_LOGGER_ENDL;
                        }
                }

                void TCPConnection::eventBundleForwarded()
                {
                        try {
                                const dtn::data::MetaBundle bundle = _sentqueue.getnpop();

                                // signal completion of the transfer
                                TransferCompletedEvent::raise(_node.getEID(), bundle);

                                // raise bundle event
                                dtn::core::BundleEvent::raise(bundle, BUNDLE_FORWARDED);

                                // set ACK to zero
                                _lastack = 0;
                        } catch (const ibrcommon::QueueUnblockedException&) {
                                // pop on empty queue!
                                IBRCOMMON_LOGGER(error) << "transfer completed without a bundle in queue" << IBRCOMMON_LOGGER_ENDL;
                        }
                }

                void TCPConnection::eventBundleAck(size_t ack)
                {
                        _lastack = ack;
                }

                void TCPConnection::initialize()
                {
                        // start the receiver for incoming bundles + handshake
                        try {
                                start();
                        } catch (const ibrcommon::ThreadException &ex) {
                                IBRCOMMON_LOGGER(error) << "failed to start thread in TCPConnection\n" << ex.what() << IBRCOMMON_LOGGER_ENDL;
                        }
                }

                void TCPConnection::shutdown()
                {
                        // shutdown
                        _stream.shutdown(StreamConnection::CONNECTION_SHUTDOWN_ERROR);

                        try {
                                // abort the connection thread
                                ibrcommon::DetachedThread::stop();
                        } catch (const ibrcommon::ThreadException &ex) {
                                IBRCOMMON_LOGGER_DEBUG(50) << "TCPConnection::shutdown(): ThreadException (" << ex.what() << ")" << IBRCOMMON_LOGGER_ENDL;
                        }
                }

                bool TCPConnection::__cancellation()
                {
                        // close the stream
                        try {
                                (*_tcpstream).close();
                        } catch (const ibrcommon::ConnectionClosedException&) { };

                        return true;
                }

                void TCPConnection::finally()
                {
                        IBRCOMMON_LOGGER_DEBUG(60) << "TCPConnection down" << IBRCOMMON_LOGGER_ENDL;

                        try {
                                // shutdown the sender thread
                                _sender.stop();
                        } catch (const std::exception&) { };

                        // close the tcpstream
                        try {
                                _tcpstream->close();
                        } catch (const ibrcommon::ConnectionClosedException&) { };

                        try {
                                _callback.connectionDown(this);
                        } catch (const ibrcommon::MutexException&) { };

                        // clear the queue
                        clearQueue();
                }

                void TCPConnection::setup()
                {
                        // variables for address and port
                        std::string address = "0.0.0.0";
                        unsigned int port = 0;

                        // try to connect to the other side
                        try {
                                const std::list<dtn::core::Node::URI> uri_list = _node.get(dtn::core::Node::CONN_TCPIP);

                                for (std::list<dtn::core::Node::URI>::const_iterator iter = uri_list.begin(); iter != uri_list.end(); iter++)
                                {
                                        try {
                                                // decode address and port
                                                const dtn::core::Node::URI &uri = uri_list.front();
                                                uri.decode(address, port);

                                                ibrcommon::tcpclient &client = dynamic_cast<ibrcommon::tcpclient&>(*_tcpstream);
                                                client.open(address, port, _timeout);

                                                if ( dtn::daemon::Configuration::getInstance().getNetwork().getTCPOptionNoDelay() )
                                                {
                                                        _tcpstream->enableNoDelay();
                                                }

                                                // add TCP connection descriptor to the node object
                                                _node.clear();
                                                _node.add( dtn::core::Node::URI(Node::NODE_CONNECTED, Node::CONN_TCPIP, uri.value) );

                                                // connection successful
                                                return;
                                        } catch (const ibrcommon::tcpclient::SocketException&) { };
                                }

                                // no connection has been established
                                throw ibrcommon::tcpclient::SocketException("no address available to connect");

                        } catch (const ibrcommon::tcpclient::SocketException&) {
                                // error on open, requeue all bundles in the queue
                                IBRCOMMON_LOGGER(warning) << "connection to " << _node.toString() << " failed" << IBRCOMMON_LOGGER_ENDL;
                                _stream.shutdown(StreamConnection::CONNECTION_SHUTDOWN_ERROR);
                                throw;
                        } catch (const bad_cast&) { };
                }

                void TCPConnection::run()
                {
                        try {
                                // do the handshake
                                _stream.handshake(_name, _timeout, _flags);

                                // start the sender
                                _sender.start();

                                while (!_stream.eof())
                                {
                                        try {
                                                // create a new empty bundle
                                                dtn::data::Bundle bundle;

                                                // deserialize the bundle
                                                (*this) >> bundle;

                                                // check the bundle
                                                if ( ( bundle._destination == EID() ) || ( bundle._source == EID() ) )
                                                {
                                                        // invalid bundle!
                                                        throw dtn::data::Validator::RejectedException("destination or source EID is null");
                                                }

                                                // increment value in the scope control hop limit block
                                                try {
                                                        dtn::data::ScopeControlHopLimitBlock &schl = bundle.getBlock<dtn::data::ScopeControlHopLimitBlock>();
                                                        schl.increment();
                                                } catch (const dtn::data::Bundle::NoSuchBlockFoundException&) { }

                                                // raise default bundle received event
                                                dtn::net::BundleReceivedEvent::raise(_peer._localeid, bundle);
                                        }
                                        catch (const dtn::data::Validator::RejectedException &ex)
                                        {
                                                // bundle rejected
                                                rejectTransmission();

                                                // display the rejection
                                                IBRCOMMON_LOGGER(warning) << "bundle has been rejected: " << ex.what() << IBRCOMMON_LOGGER_ENDL;
                                        }
                                        catch (const dtn::InvalidDataException &ex) {
                                                // bundle rejected
                                                rejectTransmission();

                                                // display the rejection
                                                IBRCOMMON_LOGGER(warning) << "invalid bundle-data received: " << ex.what() << IBRCOMMON_LOGGER_ENDL;
                                        }

                                        yield();
                                }
                        } catch (const ibrcommon::ThreadException &ex) {
                                IBRCOMMON_LOGGER(error) << "failed to start thread in TCPConnection\n" << ex.what() << IBRCOMMON_LOGGER_ENDL;
                                _stream.shutdown(StreamConnection::CONNECTION_SHUTDOWN_ERROR);
                        } catch (const std::exception &ex) {
                                IBRCOMMON_LOGGER_DEBUG(10) << "TCPConnection::run(): std::exception (" << ex.what() << ")" << IBRCOMMON_LOGGER_ENDL;
                                _stream.shutdown(StreamConnection::CONNECTION_SHUTDOWN_ERROR);
                        }
                }


                TCPConnection& operator>>(TCPConnection &conn, dtn::data::Bundle &bundle)
                {
                        std::iostream &stream = conn._stream;

                        // check if the stream is still good
                        if (!stream.good()) throw ibrcommon::IOException("stream went bad");

                        dtn::data::DefaultDeserializer(stream, dtn::core::BundleCore::getInstance()) >> bundle;
                        return conn;
                }

                TCPConnection& operator<<(TCPConnection &conn, const dtn::data::Bundle &bundle)
                {
                        // prepare a measurement
                        ibrcommon::TimeMeasurement m;

                        std::iostream &stream = conn._stream;

                        // create a serializer
                        dtn::data::DefaultSerializer serializer(stream);

                        // put the bundle into the sentqueue
                        conn._sentqueue.push(bundle);

                        // start the measurement
                        m.start();

                        try {
                                // activate exceptions for this method
                                if (!stream.good()) throw ibrcommon::IOException("stream went bad");

                                // transmit the bundle
                                serializer << bundle;

                                // flush the stream
                                stream << std::flush;

                                // stop the time measurement
                                m.stop();

                                // get throughput
                                double kbytes_per_second = (serializer.getLength(bundle) / m.getSeconds()) / 1024;

                                // print out throughput
                                IBRCOMMON_LOGGER_DEBUG(5) << "transfer finished after " << m << " with "
                                                << std::setiosflags(std::ios::fixed) << std::setprecision(2) << kbytes_per_second << " kb/s" << IBRCOMMON_LOGGER_ENDL;

                        } catch (const ibrcommon::Exception &ex) {
                                // the connection not available
                                IBRCOMMON_LOGGER_DEBUG(10) << "connection error: " << ex.what() << IBRCOMMON_LOGGER_ENDL;

                                // forward exception
                                throw;
                        }

                        return conn;
                }

                TCPConnection::Sender::Sender(TCPConnection &connection, size_t &keepalive_timeout)
                 : _connection(connection), _keepalive_timeout(keepalive_timeout)
                {
                }

                TCPConnection::Sender::~Sender()
                {
                }

                bool TCPConnection::Sender::__cancellation()
                {
                        // cancel the main thread in here
                        ibrcommon::Queue<dtn::data::BundleID>::abort();

                        return true;
                }

                void TCPConnection::Sender::run()
                {
                        try {
                                dtn::core::BundleStorage &storage = dtn::core::BundleCore::getInstance().getStorage();

                                while (_connection.good())
                                {
                                        try {
                                                _current_transfer = ibrcommon::Queue<dtn::data::BundleID>::getnpop(true, _keepalive_timeout);

                                                try {
                                                        // read the bundle out of the storage
                                                        dtn::data::Bundle bundle = storage.get(_current_transfer);

#ifdef WITH_BUNDLE_SECURITY
                                                        const dtn::daemon::Configuration::Security::Level seclevel =
                                                                        dtn::daemon::Configuration::getInstance().getSecurity().getLevel();

                                                        if (seclevel & dtn::daemon::Configuration::Security::SECURITY_LEVEL_AUTHENTICATED)
                                                        {
                                                                try {
                                                                        dtn::security::SecurityManager::getInstance().auth(bundle);
                                                                } catch (const dtn::security::SecurityManager::KeyMissingException&) {
                                                                        // sign requested, but no key is available
                                                                        IBRCOMMON_LOGGER(warning) << "No key available for sign process." << IBRCOMMON_LOGGER_ENDL;
                                                                }
                                                        }
#endif
                                                        // send bundle
                                                        _connection << bundle;
                                                } catch (const dtn::core::BundleStorage::NoBundleFoundException&) {
                                                        // send transfer aborted event
                                                        TransferAbortedEvent::raise(_connection._node.getEID(), _current_transfer, dtn::net::TransferAbortedEvent::REASON_BUNDLE_DELETED);
                                                }
                                                
                                                // unset the current transfer
                                                _current_transfer = dtn::data::BundleID();
                                                
                                        } catch (const ibrcommon::QueueUnblockedException &ex) {
                                                switch (ex.reason)
                                                {
                                                        case ibrcommon::QueueUnblockedException::QUEUE_ERROR:
                                                        case ibrcommon::QueueUnblockedException::QUEUE_ABORT:
                                                                throw;
                                                        case ibrcommon::QueueUnblockedException::QUEUE_TIMEOUT:
                                                        {
                                                                // send a keepalive
                                                                _connection.keepalive();
                                                        }
                                                }
                                        }

                                        // idle a little bit
                                        yield();
                                }
                        } catch (const ibrcommon::QueueUnblockedException &ex) {
                                IBRCOMMON_LOGGER_DEBUG(50) << "TCPConnection::Sender::run(): aborted" << IBRCOMMON_LOGGER_ENDL;
                                return;
                        } catch (const std::exception &ex) {
                                IBRCOMMON_LOGGER_DEBUG(10) << "TCPConnection::Sender terminated by exception: " << ex.what() << IBRCOMMON_LOGGER_ENDL;
                        }

                        _connection.stop();
                }

                void TCPConnection::clearQueue()
                {
                        // requeue all bundles still queued
                        try {
                                while (true)
                                {
                                        const dtn::data::BundleID id = _sender.getnpop();

                                        // raise transfer abort event for all bundles without an ACK
                                        dtn::routing::RequeueBundleEvent::raise(_node.getEID(), id);
                                }
                        } catch (const ibrcommon::QueueUnblockedException&) {
                                // queue emtpy
                        }

                        // requeue all bundles still in transit
                        try {
                                while (true)
                                {
                                        const dtn::data::BundleID id = _sentqueue.getnpop();

                                        if (_lastack > 0)
                                        {
                                                // some data are already acknowledged, make a fragment?
                                                //TODO: make a fragment
                                                dtn::routing::RequeueBundleEvent::raise(_node.getEID(), id);
                                        }
                                        else
                                        {
                                                // raise transfer abort event for all bundles without an ACK
                                                dtn::routing::RequeueBundleEvent::raise(_node.getEID(), id);
                                        }

                                        // set last ack to zero
                                        _lastack = 0;
                                }
                        } catch (const ibrcommon::QueueUnblockedException&) {
                                // queue emtpy
                        }
                }
                
#ifdef WITH_TLS
                void dtn::net::TCPConnection::enableTLS()
                {
                        _flags |= dtn::streams::StreamContactHeader::REQUEST_TLS;
                }
#endif

                void TCPConnection::keepalive()
                {
                        _stream.keepalive();
                }

                bool TCPConnection::good() const
                {
                        return _tcpstream->good();
                }

                void TCPConnection::Sender::finally()
                {
                        // notify the aborted transfer of the last bundle
                        if (_current_transfer != dtn::data::BundleID())
                        {
                                dtn::routing::RequeueBundleEvent::raise(_connection._node.getEID(), _current_transfer);
                        }
                }

                bool TCPConnection::match(const dtn::core::Node &n) const
                {
                        return (_node == n);
                }

                bool TCPConnection::match(const dtn::data::EID &destination) const
                {
                        return (_node.getEID() == destination.getNode());
                }

                bool TCPConnection::match(const NodeEvent &evt) const
                {
                        const dtn::core::Node &n = evt.getNode();
                        return match(n);
                }
        }
}