ibrdtn/ibrdtn/data/Serializer.cpp

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#include "ibrdtn/data/Serializer.h"
#include "ibrdtn/data/Bundle.h"
#include "ibrdtn/data/Block.h"
#include "ibrdtn/data/BundleString.h"
#include "ibrdtn/data/StatusReportBlock.h"
#include "ibrdtn/data/CustodySignalBlock.h"
#include "ibrdtn/data/ExtensionBlock.h"
#include <ibrcommon/refcnt_ptr.h>
#include <ibrcommon/Logger.h>
#include <list>

#ifdef __DEVELOPMENT_ASSERTIONS__
#include <cassert>
#endif

namespace dtn
{
        namespace data
        {
                DefaultSerializer::DefaultSerializer(std::ostream& stream)
                 : _stream(stream), _compressable(false)
                {
                }

                DefaultSerializer::DefaultSerializer(std::ostream& stream, const Dictionary &d)
                 : _stream(stream), _dictionary(d), _compressable(false)
                {
                }

                void DefaultSerializer::rebuildDictionary(const dtn::data::Bundle &obj)
                {
                        // clear the dictionary
                        _dictionary.clear();

                        // rebuild the dictionary
                        _dictionary.add(obj._destination);
                        _dictionary.add(obj._source);
                        _dictionary.add(obj._reportto);
                        _dictionary.add(obj._custodian);

                        // add EID of all secondary blocks
                        std::list<refcnt_ptr<Block> > list = obj._blocks._blocks;

                        for (std::list<refcnt_ptr<Block> >::const_iterator iter = list.begin(); iter != list.end(); iter++)
                        {
                                const Block &b = (*(*iter));
                                _dictionary.add( b.getEIDList() );
                        }
                }

                Serializer& DefaultSerializer::operator <<(const dtn::data::Bundle& obj)
                {
                        // rebuild the dictionary
                        rebuildDictionary(obj);

                        // check if the bundle header could be compressed
                        _compressable = isCompressable(obj);

                        // serialize the primary block
                        (*this) << (PrimaryBlock&)obj;

                        // serialize all secondary blocks
                        std::list<refcnt_ptr<Block> > list = obj._blocks._blocks;
                        
                        for (std::list<refcnt_ptr<Block> >::const_iterator iter = list.begin(); iter != list.end(); iter++)
                        {
                                const Block &b = (*(*iter));
                                (*this) << b;
                        }

                        return (*this);
                }

                bool DefaultSerializer::isCompressable(const dtn::data::Bundle &obj) const
                {
                        // check if all EID are compressable
                        bool compressable = ( obj._source.isCompressable() &&
                                        obj._destination.isCompressable() &&
                                        obj._reportto.isCompressable() &&
                                        obj._custodian.isCompressable() );

                        if (compressable)
                        {
                                // add EID of all secondary blocks
                                std::list<refcnt_ptr<Block> > list = obj._blocks._blocks;

                                for (std::list<refcnt_ptr<Block> >::const_iterator iter = list.begin(); iter != list.end(); iter++)
                                {
                                        const Block &b = (*(*iter));
                                        const std::list<dtn::data::EID> eids = b.getEIDList();

                                        for (std::list<dtn::data::EID>::const_iterator eit = eids.begin(); eit != eids.end(); eit++)
                                        {
                                                const dtn::data::EID &eid = (*eit);
                                                if (!eid.isCompressable())
                                                {
                                                        return false;
                                                }
                                        }
                                }
                        }

                        return compressable;
                }

                Serializer& DefaultSerializer::operator <<(const dtn::data::PrimaryBlock& obj)
                {
                        _stream << dtn::data::BUNDLE_VERSION;           // bundle version
                        _stream << dtn::data::SDNV(obj._procflags);     // processing flags

                        // predict the block length
                        size_t len = 0;
                        dtn::data::SDNV primaryheader[14];

                        primaryheader[8] = SDNV(obj._timestamp);                // timestamp
                        primaryheader[9] = SDNV(obj._sequencenumber);   // sequence number
                        primaryheader[10] = SDNV(obj._lifetime);                // lifetime

                        pair<size_t, size_t> ref;

                        if (_compressable)
                        {
                                // destination reference
                                ref = obj._destination.getCompressed();
                                primaryheader[0] = SDNV(ref.first);
                                primaryheader[1] = SDNV(ref.second);

                                // source reference
                                ref = obj._source.getCompressed();
                                primaryheader[2] = SDNV(ref.first);
                                primaryheader[3] = SDNV(ref.second);

                                // reportto reference
                                ref = obj._reportto.getCompressed();
                                primaryheader[4] = SDNV(ref.first);
                                primaryheader[5] = SDNV(ref.second);

                                // custodian reference
                                ref = obj._custodian.getCompressed();
                                primaryheader[6] = SDNV(ref.first);
                                primaryheader[7] = SDNV(ref.second);

                                // dictionary size is zero in a compressed bundle header
                                primaryheader[11] = SDNV(0);
                        }
                        else
                        {
                                // destination reference
                                ref = _dictionary.getRef(obj._destination);
                                primaryheader[0] = SDNV(ref.first);
                                primaryheader[1] = SDNV(ref.second);

                                // source reference
                                ref = _dictionary.getRef(obj._source);
                                primaryheader[2] = SDNV(ref.first);
                                primaryheader[3] = SDNV(ref.second);

                                // reportto reference
                                ref = _dictionary.getRef(obj._reportto);
                                primaryheader[4] = SDNV(ref.first);
                                primaryheader[5] = SDNV(ref.second);

                                // custodian reference
                                ref = _dictionary.getRef(obj._custodian);
                                primaryheader[6] = SDNV(ref.first);
                                primaryheader[7] = SDNV(ref.second);

                                // dictionary size
                                primaryheader[11] = SDNV(_dictionary.getSize());
                                len += _dictionary.getSize();
                        }

                        for (int i = 0; i < 12; i++)
                        {
                                len += primaryheader[i].getLength();
                        }

                        if (obj.get(dtn::data::Bundle::FRAGMENT))
                        {
                                primaryheader[12] = SDNV(obj._fragmentoffset);
                                primaryheader[13] = SDNV(obj._appdatalength);

                                len += primaryheader[12].getLength();
                                len += primaryheader[13].getLength();
                        }

                        // write the block length
                        _stream << SDNV(len);

                        /*
                         * write the ref block of the dictionary
                         * this includes scheme and ssp for destination, source, reportto and custodian.
                         */
                        for (int i = 0; i < 11; i++)
                        {
                                _stream << primaryheader[i];
                        }

                        if (_compressable)
                        {
                                // write the size of the dictionary (always zero here)
                                _stream << primaryheader[11];
                        }
                        else
                        {
                                // write size of dictionary + bytearray
                                _stream << _dictionary;
                        }

                        if (obj.get(dtn::data::Bundle::FRAGMENT))
                        {
                                _stream << primaryheader[12]; // FRAGMENTATION_OFFSET
                                _stream << primaryheader[13]; // APPLICATION_DATA_LENGTH
                        }
                        
                        return (*this);
                }

                Serializer& DefaultSerializer::operator <<(const dtn::data::Block& obj)
                {
                        _stream << obj._blocktype;
                        _stream << dtn::data::SDNV(obj._procflags);

#ifdef __DEVELOPMENT_ASSERTIONS__
                        // test: BLOCK_CONTAINS_EIDS => (_eids.size() > 0)
                        assert(!obj.get(Block::BLOCK_CONTAINS_EIDS) || (obj._eids.size() > 0));
#endif

                        if (obj.get(Block::BLOCK_CONTAINS_EIDS))
                        {
                                _stream << SDNV(obj._eids.size());
                                for (std::list<dtn::data::EID>::const_iterator it = obj._eids.begin(); it != obj._eids.end(); it++)
                                {
                                        pair<size_t, size_t> offsets;

                                        if (_compressable)
                                        {
                                                offsets = (*it).getCompressed();
                                        }
                                        else
                                        {
                                                offsets = _dictionary.getRef(*it);
                                        }

                                        _stream << SDNV(offsets.first);
                                        _stream << SDNV(offsets.second);
                                }
                        }

                        // write size of the payload in the block
                        _stream << SDNV(obj.getLength());

                        // write the payload of the block
                        obj.serialize(_stream);

                        return (*this);
                }

                size_t DefaultSerializer::getLength(const dtn::data::Bundle &obj)
                {
                        // rebuild the dictionary
                        rebuildDictionary(obj);

                        size_t len = 0;
                        len += getLength( (PrimaryBlock&)obj );
                        
                        // add size of all blocks
                        std::list<refcnt_ptr<Block> > list = obj._blocks._blocks;

                        for (std::list<refcnt_ptr<Block> >::const_iterator iter = list.begin(); iter != list.end(); iter++)
                        {
                                const Block &b = (*(*iter));
                                len += getLength( b );
                        }

                        return len;
                }

                size_t DefaultSerializer::getLength(const dtn::data::PrimaryBlock& obj) const
                {
                        size_t len = 0;

                        len += sizeof(dtn::data::BUNDLE_VERSION);               // bundle version
                        len += dtn::data::SDNV(obj._procflags).getLength();     // processing flags

                        // primary header
                        dtn::data::SDNV primaryheader[14];
                        pair<size_t, size_t> ref;

                        if (_compressable)
                        {
                                // destination reference
                                ref = obj._destination.getCompressed();
                                primaryheader[0] = SDNV(ref.first);
                                primaryheader[1] = SDNV(ref.second);

                                // source reference
                                ref = obj._source.getCompressed();
                                primaryheader[2] = SDNV(ref.first);
                                primaryheader[3] = SDNV(ref.second);

                                // reportto reference
                                ref = obj._reportto.getCompressed();
                                primaryheader[4] = SDNV(ref.first);
                                primaryheader[5] = SDNV(ref.second);

                                // custodian reference
                                ref = obj._custodian.getCompressed();
                                primaryheader[6] = SDNV(ref.first);
                                primaryheader[7] = SDNV(ref.second);

                                // dictionary size
                                primaryheader[11] = SDNV(0);
                        }
                        else
                        {
                                // destination reference
                                ref = _dictionary.getRef(obj._destination);
                                primaryheader[0] = SDNV(ref.first);
                                primaryheader[1] = SDNV(ref.second);

                                // source reference
                                ref = _dictionary.getRef(obj._source);
                                primaryheader[2] = SDNV(ref.first);
                                primaryheader[3] = SDNV(ref.second);

                                // reportto reference
                                ref = _dictionary.getRef(obj._reportto);
                                primaryheader[4] = SDNV(ref.first);
                                primaryheader[5] = SDNV(ref.second);

                                // custodian reference
                                ref = _dictionary.getRef(obj._custodian);
                                primaryheader[6] = SDNV(ref.first);
                                primaryheader[7] = SDNV(ref.second);

                                // dictionary size
                                primaryheader[11] = SDNV(_dictionary.getSize());
                        }

                        // timestamp
                        primaryheader[8] = SDNV(obj._timestamp);

                        // sequence number
                        primaryheader[9] = SDNV(obj._sequencenumber);

                        // lifetime
                        primaryheader[10] = SDNV(obj._lifetime);

                        for (int i = 0; i < 11; i++)
                        {
                                len += primaryheader[i].getLength();
                        }

                        if (_compressable)
                        {
                                // write the size of the dictionary (always zero here)
                                len += primaryheader[11].getLength();
                        }
                        else
                        {
                                // write size of dictionary + bytearray
                                len += primaryheader[11].getLength();
                                len += _dictionary.getSize();
                        }

                        if (obj.get(dtn::data::Bundle::FRAGMENT))
                        {
                                primaryheader[12] = SDNV(obj._fragmentoffset);
                                primaryheader[13] = SDNV(obj._appdatalength);

                                len += primaryheader[12].getLength();
                                len += primaryheader[13].getLength();
                        }

                        len += SDNV(len).getLength();

                        return len;
                }

                size_t DefaultSerializer::getLength(const dtn::data::Block &obj) const
                {
                        size_t len = 0;

                        len += sizeof(obj._blocktype);
                        len += dtn::data::SDNV(obj._procflags).getLength();

#ifdef __DEVELOPMENT_ASSERTIONS__
                        // test: BLOCK_CONTAINS_EIDS => (_eids.size() > 0)
                        assert(!obj.get(Block::BLOCK_CONTAINS_EIDS) || (obj._eids.size() > 0));
#endif

                        if (obj.get(Block::BLOCK_CONTAINS_EIDS))
                        {
                                len += dtn::data::SDNV(obj._eids.size()).getLength();
                                for (std::list<dtn::data::EID>::const_iterator it = obj._eids.begin(); it != obj._eids.end(); it++)
                                {
                                        pair<size_t, size_t> offsets = _dictionary.getRef(*it);
                                        len += SDNV(offsets.first).getLength();
                                        len += SDNV(offsets.second).getLength();
                                }
                        }

                        // size of the payload in the block
                        len += obj.getLength();

                        return len;
                }

                DefaultDeserializer::DefaultDeserializer(std::istream& stream)
                 : _stream(stream), _validator(_default_validator), _compressed(false)
                {
                }

                DefaultDeserializer::DefaultDeserializer(std::istream &stream, Validator &v)
                 : _stream(stream), _validator(v), _compressed(false)
                {
                }

                DefaultDeserializer::DefaultDeserializer(std::istream &stream, const Dictionary &d)
                 : _stream(stream), _validator(_default_validator), _dictionary(d), _compressed(false)
                {
                }

                Deserializer& DefaultDeserializer::operator >>(dtn::data::Bundle& obj)
                {
                        // clear all blocks
                        obj.clearBlocks();

                        // read the primary block
                        (*this) >> (PrimaryBlock&)obj;

                        // read until the last block
                        bool lastblock = false;

                        // read all BLOCKs
                        while (!_stream.eof() && !lastblock)
                        {
                                char block_type;

                                // BLOCK_TYPE
                                block_type = _stream.peek();

                                switch (block_type)
                                {
                                        case 0:
                                        {
                                                throw dtn::InvalidDataException("block type is zero");
                                                break;
                                        }

                                        case dtn::data::PayloadBlock::BLOCK_TYPE:
                                        {
                                                if (obj.get(dtn::data::Bundle::APPDATA_IS_ADMRECORD))
                                                {
                                                        // create a temporary block
                                                        dtn::data::ExtensionBlock &block = obj.push_back<dtn::data::ExtensionBlock>();

                                                        // read the block data
                                                        (*this) >> block;

                                                        // access the payload to get the first byte
                                                        char admfield;
                                                        ibrcommon::BLOB::Reference ref = block.getBLOB();
                                                        ref.iostream()->get(admfield);

                                                        // write the block into a temporary stream
                                                        stringstream ss;
                                                        DefaultSerializer serializer(ss, _dictionary);
                                                        DefaultDeserializer deserializer(ss, _dictionary);

                                                        serializer << block;

                                                        // remove the temporary block
                                                        obj.remove(block);

                                                        switch (admfield >> 4)
                                                        {
                                                                case 1:
                                                                {
                                                                        dtn::data::StatusReportBlock &block = obj.push_back<dtn::data::StatusReportBlock>();
                                                                        deserializer >> block;
                                                                        lastblock = block.get(Block::LAST_BLOCK);
                                                                        break;
                                                                }

                                                                case 2:
                                                                {
                                                                        dtn::data::CustodySignalBlock &block = obj.push_back<dtn::data::CustodySignalBlock>();
                                                                        deserializer >> block;
                                                                        lastblock = block.get(Block::LAST_BLOCK);
                                                                        break;
                                                                }

                                                                default:
                                                                {
                                                                        // drop unknown administrative block
                                                                        break;
                                                                }
                                                        }

                                                }
                                                else
                                                {
                                                        dtn::data::PayloadBlock &block = obj.push_back<dtn::data::PayloadBlock>();
                                                        (*this) >> block;

                                                        lastblock = block.get(Block::LAST_BLOCK);
                                                }
                                                break;
                                        }

                                        default:
                                        {
                                                // get a extension block factory
                                                try {
                                                        ExtensionBlock::Factory &f = dtn::data::ExtensionBlock::Factory::get(block_type);

                                                        dtn::data::Block &block = obj.push_back(f);
                                                        (*this) >> block;
                                                        lastblock = block.get(Block::LAST_BLOCK);

                                                        if (block.get(dtn::data::Block::DISCARD_IF_NOT_PROCESSED))
                                                        {
                                                                IBRCOMMON_LOGGER_DEBUG(5) << "unprocessable block in bundle " << obj.toString() << " has been removed" << IBRCOMMON_LOGGER_ENDL;

                                                                // remove the block
                                                                obj.remove(block);
                                                        }
                                                }
                                                catch (const ibrcommon::Exception &ex)
                                                {
                                                        dtn::data::ExtensionBlock &block = obj.push_back<dtn::data::ExtensionBlock>();
                                                        (*this) >> block;
                                                        lastblock = block.get(Block::LAST_BLOCK);

                                                        if (block.get(dtn::data::Block::DISCARD_IF_NOT_PROCESSED))
                                                        {
                                                                IBRCOMMON_LOGGER_DEBUG(5) << "unprocessable block in bundle " << obj.toString() << " has been removed" << IBRCOMMON_LOGGER_ENDL;

                                                                // remove the block
                                                                obj.remove(block);
                                                        }
                                                }
                                                break;
                                        }
                                }
                        }

                        // validate this bundle
                        _validator.validate(obj);

                        return (*this);
                }

                Deserializer& DefaultDeserializer::operator >>(dtn::data::PrimaryBlock& obj)
                {
                        char version = 0;
                        SDNV tmpsdnv;
                        SDNV blocklength;

                        // check for the right version
                        _stream.get(version);
                        if (version != dtn::data::BUNDLE_VERSION) throw dtn::InvalidProtocolException("Bundle version differ from ours.");

                        // PROCFLAGS
                        _stream >> tmpsdnv;     // processing flags
                        obj._procflags = tmpsdnv.getValue();

                        // BLOCK LENGTH
                        _stream >> blocklength;

                        // EID References
                        pair<SDNV, SDNV> ref[4];
                        for (int i = 0; i < 4; i++)
                        {
                                _stream >> ref[i].first;
                                _stream >> ref[i].second;
                        }

                        // timestamp
                        _stream >> tmpsdnv;
                        obj._timestamp = tmpsdnv.getValue();

                        // sequence number
                        _stream >> tmpsdnv;
                        obj._sequencenumber = tmpsdnv.getValue();

                        // lifetime
                        _stream >> tmpsdnv;
                        obj._lifetime = tmpsdnv.getValue();

                        try {
                                // dictionary
                                _stream >> _dictionary;

                                // decode EIDs
                                obj._destination = _dictionary.get(ref[0].first.getValue(), ref[0].second.getValue());
                                obj._source = _dictionary.get(ref[1].first.getValue(), ref[1].second.getValue());
                                obj._reportto = _dictionary.get(ref[2].first.getValue(), ref[2].second.getValue());
                                obj._custodian = _dictionary.get(ref[3].first.getValue(), ref[3].second.getValue());
                                _compressed = false;
                        } catch (const dtn::InvalidDataException&) {
                                // error while reading the dictionary. We assume that this is a compressed bundle header.
                                obj._destination = dtn::data::EID(ref[0].first.getValue(), ref[0].second.getValue());
                                obj._source = dtn::data::EID(ref[1].first.getValue(), ref[1].second.getValue());
                                obj._reportto = dtn::data::EID(ref[2].first.getValue(), ref[2].second.getValue());
                                obj._custodian = dtn::data::EID(ref[3].first.getValue(), ref[3].second.getValue());
                                _compressed = true;
                        }

                        // fragmentation?
                        if (obj.get(dtn::data::Bundle::FRAGMENT))
                        {
                                _stream >> tmpsdnv;
                                obj._fragmentoffset = tmpsdnv.getValue();

                                _stream >> tmpsdnv;
                                obj._appdatalength = tmpsdnv.getValue();
                        }
                        
                        // validate this primary block
                        _validator.validate(obj);

                        return (*this);
                }

                Deserializer& DefaultDeserializer::operator >>(dtn::data::Block& obj)
                {
                        dtn::data::SDNV procflags_sdnv;
                        _stream.get(obj._blocktype);
                        _stream >> procflags_sdnv;

                        // set the processing flags but do not overwrite the lastblock bit
                        obj._procflags = procflags_sdnv.getValue() & (~(dtn::data::Block::LAST_BLOCK) | obj._procflags);

                        // read EIDs
                        if ( obj.get(dtn::data::Block::BLOCK_CONTAINS_EIDS))
                        {
                                SDNV eidcount;
                                _stream >> eidcount;

                                for (unsigned int i = 0; i < eidcount.getValue(); i++)
                                {
                                        SDNV scheme, ssp;
                                        _stream >> scheme;
                                        _stream >> ssp;

                                        if (_compressed)
                                        {
                                                obj.addEID( dtn::data::EID(scheme.getValue(), ssp.getValue()) );
                                        }
                                        else
                                        {
                                                obj.addEID( _dictionary.get(scheme.getValue(), ssp.getValue()) );
                                        }
                                }
                        }

                        // read the size of the payload in the block
                        SDNV block_size;
                        _stream >> block_size;
                        obj._blocksize = block_size.getValue();

                        // validate this block
                        _validator.validate(obj, block_size.getValue());

                        // read the payload of the block
                        obj.deserialize(_stream);

                        return (*this);
                }

                AcceptValidator::AcceptValidator()
                {
                }

                AcceptValidator::~AcceptValidator()
                {
                }

                void AcceptValidator::validate(const dtn::data::PrimaryBlock&) const throw (RejectedException)
                {
                }

                void AcceptValidator::validate(const dtn::data::Block&, const size_t) const throw (RejectedException)
                {

                }

                void AcceptValidator::validate(const dtn::data::Bundle&) const throw (RejectedException)
                {

                }

                SeparateSerializer::SeparateSerializer(std::ostream& stream)
                 : DefaultSerializer(stream)
                {
                }

                SeparateSerializer::~SeparateSerializer()
                {
                }

                Serializer& SeparateSerializer::operator <<(const dtn::data::Block& obj)
                {
                        _stream << obj._blocktype;
                        _stream << dtn::data::SDNV(obj._procflags);

#ifdef __DEVELOPMENT_ASSERTIONS__
                        // test: BLOCK_CONTAINS_EIDS => (_eids.size() > 0)
                        assert(!obj.get(Block::BLOCK_CONTAINS_EIDS) || (obj._eids.size() > 0));
#endif

                        if (obj.get(Block::BLOCK_CONTAINS_EIDS))
                        {
                                _stream << SDNV(obj._eids.size());
                                for (std::list<dtn::data::EID>::const_iterator it = obj._eids.begin(); it != obj._eids.end(); it++)
                                {
                                        dtn::data::BundleString str((*it).getString());
                                        _stream << str;
                                }
                        }

                        // write size of the payload in the block
                        _stream << SDNV(obj.getLength());

                        // write the payload of the block
                        obj.serialize(_stream);

                        return (*this);
                }

                size_t SeparateSerializer::getLength(const dtn::data::Block &obj) const
                {
                        size_t len = 0;

                        len += sizeof(obj._blocktype);
                        len += dtn::data::SDNV(obj._procflags).getLength();

#ifdef __DEVELOPMENT_ASSERTIONS__
                        // test: BLOCK_CONTAINS_EIDS => (_eids.size() > 0)
                        assert(!obj.get(Block::BLOCK_CONTAINS_EIDS) || (obj._eids.size() > 0));
#endif

                        if (obj.get(Block::BLOCK_CONTAINS_EIDS))
                        {
                                len += dtn::data::SDNV(obj._eids.size()).getLength();
                                for (std::list<dtn::data::EID>::const_iterator it = obj._eids.begin(); it != obj._eids.end(); it++)
                                {
                                        dtn::data::BundleString str((*it).getString());
                                        len += str.getLength();
                                }
                        }

                        // size of the payload in the block
                        len += obj.getLength();

                        return len;
                }

                SeparateDeserializer::SeparateDeserializer(std::istream& stream, Bundle &b)
                 : DefaultDeserializer(stream), _bundle(b)
                {
                }

                SeparateDeserializer::~SeparateDeserializer()
                {
                }

                void SeparateDeserializer::readBlock()
                {
                        char block_type;

                        // BLOCK_TYPE
                        block_type = _stream.peek();

                        switch (block_type)
                        {
                                case 0:
                                {
                                        throw dtn::InvalidDataException("block type is zero");
                                        break;
                                }

                                case dtn::data::PayloadBlock::BLOCK_TYPE:
                                {
                                        if (_bundle.get(dtn::data::Bundle::APPDATA_IS_ADMRECORD))
                                        {
                                                // create a temporary block
                                                dtn::data::ExtensionBlock &block = _bundle.push_back<dtn::data::ExtensionBlock>();

                                                // remember the current read position
                                                int blockbegin = _stream.tellg();

                                                // read the block data
                                                (*this) >> block;

                                                // access the payload to get the first byte
                                                char admfield;
                                                ibrcommon::BLOB::Reference ref = block.getBLOB();
                                                ref.iostream()->get(admfield);

                                                // remove the temporary block
                                                _bundle.remove(block);

                                                // reset the read pointer
                                                // BEWARE: this will not work on non-buffered streams like TCP!
                                                _stream.seekg(blockbegin);

                                                switch (admfield >> 4)
                                                {
                                                        case 1:
                                                        {
                                                                dtn::data::StatusReportBlock &block = _bundle.push_back<dtn::data::StatusReportBlock>();
                                                                (*this) >> block;
                                                                break;
                                                        }

                                                        case 2:
                                                        {
                                                                dtn::data::CustodySignalBlock &block = _bundle.push_back<dtn::data::CustodySignalBlock>();
                                                                (*this) >> block;
                                                                break;
                                                        }

                                                        default:
                                                        {
                                                                // drop unknown administrative block
                                                                break;
                                                        }
                                                }

                                        }
                                        else
                                        {
                                                dtn::data::PayloadBlock &block = _bundle.push_back<dtn::data::PayloadBlock>();
                                                (*this) >> block;
                                        }
                                        break;
                                }

                                default:
                                {
                                        // get a extension block factory
                                        try {
                                                ExtensionBlock::Factory &f = dtn::data::ExtensionBlock::Factory::get(block_type);
                                                dtn::data::Block &block = _bundle.push_back(f);
                                                (*this) >> block;
                                        } catch (const ibrcommon::Exception &ex) {
                                                dtn::data::ExtensionBlock &block = _bundle.push_back<dtn::data::ExtensionBlock>();
                                                (*this) >> block;
                                        }
                                        break;
                                }
                        }
                }

                Deserializer&  SeparateDeserializer::operator >>(dtn::data::Block& obj)
                {
                        dtn::data::SDNV procflags_sdnv;
                        _stream.get(obj._blocktype);
                        _stream >> procflags_sdnv;
                        obj._procflags = procflags_sdnv.getValue();

                        // read EIDs
                        if ( obj.get(dtn::data::Block::BLOCK_CONTAINS_EIDS))
                        {
                                SDNV eidcount;
                                _stream >> eidcount;

                                for (unsigned int i = 0; i < eidcount.getValue(); i++)
                                {
                                        dtn::data::BundleString str;
                                        _stream >> str;
                                        obj.addEID(dtn::data::EID(str));
                                }
                        }

                        // read the size of the payload in the block
                        SDNV block_size;
                        _stream >> block_size;
                        obj._blocksize = block_size.getValue();

                        // validate this block
                        _validator.validate(obj, block_size.getValue());

                        // read the payload of the block
                        obj.deserialize(_stream);

                        return (*this);
                }
        }
}