Packets/MPEGDVBBundle/DTCPPacket.hh

   1 // $Id$
   2 //
   3 // Copyright (C) 2007
   4 // Fraunhofer Institut fuer offene Kommunikationssysteme (FOKUS)
   5 // Kompetenzzentrum NETwork research (NET)
   6 //     David Wagner <david.wagner@fokus.fraunhofer.de>
   7 //
   8 // This program is free software; you can redistribute it and/or modify
   9 // it under the terms of the GNU General Public License as published by
  10 // the Free Software Foundation; either version 2 of the License, or
  11 // (at your option) any later version.
  12 //
  13 // This program is distributed in the hope that it will be useful,
  14 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 // GNU General Public License for more details.
  17 //
  18 // You should have received a copy of the GNU General Public License
  19 // along with this program; if not, write to the
  20 // Free Software Foundation, Inc.,
  21 // 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  22
  23
  24 #ifndef DTCPPACKET_HH_
  25 #define DTCPPACKET_HH_
  26
  27 #include "../../Packets/Packets.hh"
  28 #include "../../Packets/DefaultBundle/IPv4Packet.hh"
  29 #include "../../Packets/DefaultBundle/IPv6Packet.hh"
  30
  31 namespace senf {
  32
  33     //first we have to define some helpers
  34     struct DTCPIPv4AddressListParser : public PacketParserBase {
  35 #       include SENF_PARSER()
  36         SENF_PARSER_PRIVATE_FIELD ( num_of_fbips, UInt8Parser );
  37         SENF_PARSER_PRIVATE_FIELD ( reserved ,    UInt8Parser );   //must be zero
  38         SENF_PARSER_VEC_N         ( fbiplist,     num_of_fbips, INet4AddressParser );
  39
  40         SENF_PARSER_FINALIZE(DTCPIPv4AddressListParser);
  41     };
  42
  43     struct DTCPIPv6AddressListParser : public PacketParserBase {
  44 #       include SENF_PARSER()
  45         SENF_PARSER_PRIVATE_FIELD ( num_of_fbips, UInt8Parser );
  46         SENF_PARSER_PRIVATE_FIELD ( reserved,     UInt8Parser );   //must be zero
  47         SENF_PARSER_VEC_N         ( fbiplist,     num_of_fbips, INet6AddressParser );
  48
  49         SENF_PARSER_FINALIZE(DTCPIPv6AddressListParser);
  50     };
  51
  52     /** \brief Parse a DTCP packet
  53
  54         Parser implementing the DTCP packet according to RFC 3077
  55
  56         \see DTCPPacketType
  57      */
  58     struct DTCPPacketParser : public PacketParserBase
  59     {
  60 #       include SENF_PARSER()
  61
  62         SENF_PARSER_BITFIELD         ( version_number,       4, unsigned );  // =1 according to rfc3077
  63         SENF_PARSER_BITFIELD         ( command,              4, unsigned );  // 1=JOIN 2=LEAVE
  64         SENF_PARSER_FIELD            ( interval,             UInt8Parser );  // 5 according to rfc3077
  65         SENF_PARSER_FIELD            ( sequence_number,      UInt16Parser );
  66         SENF_PARSER_PRIVATE_BITFIELD ( reserved,             3, unsigned );
  67         SENF_PARSER_BITFIELD         ( receive_capable_feed, 1, bool );      // 0=send only, 1=receive_capable_feed
  68         SENF_PARSER_BITFIELD         ( ip_version,           4, unsigned );  // 4=IPv4, 6=IPv6
  69         SENF_PARSER_FIELD            ( tunnel_protocol,      UInt8Parser );
  70                 /* Please consider the following comments on the implementation given in this class:
  71                  * 1. you could think of simply using SENF_PARSER_PRIVATE_VARIANT and List / Vectorparser like this:
  72                  * SENF_PARSER_PRIVATE_VARIANT  ( fbiplist,             ip_version,
  73          *                                                       (senf::VoidPacketParser) //ip_version=0
  74          *                                                       (senf::VoidPacketParser) //1
  75          *                                                       (senf::VoidPacketParser) //2
  76          *                                                       (senf::VoidPacketParser) //3
  77          *                                                       (senf::ListBParser< IPv4Packet, num_of_fbips>) //4
  78          *                                                       (senf::VoidPacketParser) //5
  79          *                                                       (senf::ListBParser< IPv6Packet, num_of_fbips>) ); //6
  80          * This can't work for two reasons:
  81          *              -SENF_PARSER_PRIVATE_VARIANT only accepts 6 templates in types but you have to start from 0.
  82          *              -you NEVER can use templated Parsers in these macros since the macro-preprocessor won't recognize the <> brackets and will
  83          *                      interpret the ","
  84          *
  85          * The first problem is solved by using (actually inventing)  SENF_PARSER_VARIANT_TRANS which has the same limitations
  86          *              concerning the number of types but isn't limited to the values used. This is achieved by a translating function
  87          *              as you can see.
  88          * The second problem is solved by introducing Helper-Parser which cover both the list and the number field. By that no
  89          *              templates have to be used.
  90                 */
  91
  92                 struct ip_version_translator {
  93                     static unsigned fromChooser(ip_version_t::value_type in) {
  94                         switch (in) {
  95                         case 4: return 0;
  96                         case 6: return 1;
  97                         }
  98                     }
  99                     static ip_version_t::value_type toChooser(unsigned in) {
 100                         switch (in) {
 101                             case 0: return 4;
 102                             case 1: return 6;
 103                         }
 104                     }
 105                 };
 106
 107         SENF_PARSER_VARIANT_TRANS    ( fbiplist,             ip_version, ip_version_translator,
 108                                                                  (senf::DTCPIPv4AddressListParser)        //IPv4
 109                                                                  (senf::DTCPIPv6AddressListParser) );     //IPv6
 110
 111         SENF_PARSER_FINALIZE(DTCPPacketParser);
 112     };
 113
 114     /** \brief DTCP packet
 115
 116         \par Packet type (typedef):
 117             \ref DTCPPacket
 118
 119         \par Fields:
 120             \ref DTCPPacketParser
 121
 122         \ingroup protocolbundle_mpegdvb
 123      */
 124     struct DTCPPacketType
 125         : public PacketTypeBase,
 126           public PacketTypeMixin<DTCPPacketType>
 127     {
 128         typedef PacketTypeMixin<DTCPPacketType> mixin;
 129         typedef ConcretePacket<DTCPPacketType> packet;
 130         typedef DTCPPacketParser parser;
 131
 132         using mixin::nextPacketRange;
 133         using mixin::init;
 134         using mixin::initSize;
 135
 136         static void dump(packet p, std::ostream & os);
 137     };
 138
 139     /** \brief DTCP packet typedef */
 140     typedef DTCPPacketType::packet DTCPPacket;
 141 }
 142
 143 #endif /*DTCPPACKET_HH_*/