Packets/MPEGDVBBundle/DTCPPacket.hh

   1 // $Id$
   2 //
   3 // Copyright (C) 2007
   4 // Fraunhofer Institute for Open Communication Systems (FOKUS)
   5 // Competence Center NETwork research (NET), St. Augustin, GERMANY
   6 //     David Wagner <dw6@berlios.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 #define DTCP_V4_MCADDRESS "224.0.0.36"
  32 #define DTCP_V6_MCADDRESS "FF02:0:0:0:0:0:1:4"
  33 #define DTCP_UDP_PORT 652
  34
  35 namespace senf {
  36
  37     //first we have to define some helpers
  38     struct DTCPIPv4AddressListParser : public PacketParserBase {
  39 #       include SENF_PARSER()
  40         SENF_PARSER_PRIVATE_FIELD ( num_of_fbips, UInt8Parser );
  41         SENF_PARSER_PRIVATE_FIELD ( reserved ,    UInt8Parser );   //must be zero
  42         SENF_PARSER_VEC_N         ( fbiplist,     num_of_fbips, INet4AddressParser );
  43
  44         SENF_PARSER_FINALIZE(DTCPIPv4AddressListParser);
  45     };
  46
  47     struct DTCPIPv6AddressListParser : public PacketParserBase {
  48 #       include SENF_PARSER()
  49         SENF_PARSER_PRIVATE_FIELD ( num_of_fbips, UInt8Parser );
  50         SENF_PARSER_PRIVATE_FIELD ( reserved,     UInt8Parser );   //must be zero
  51         SENF_PARSER_VEC_N         ( fbiplist,     num_of_fbips, INet6AddressParser );
  52
  53         SENF_PARSER_FINALIZE(DTCPIPv6AddressListParser);
  54     };
  55
  56     /** \brief Parse a DTCP packet
  57
  58         Parser implementing the DTCP packet according to RFC 3077
  59
  60         \see DTCPPacketType
  61      */
  62     struct DTCPPacketParser : public PacketParserBase
  63     {
  64 #       include SENF_PARSER()
  65
  66         SENF_PARSER_BITFIELD         ( version_number,       4, unsigned );  // =1 according to rfc3077
  67         SENF_PARSER_BITFIELD         ( command,              4, unsigned );  // 1=JOIN 2=LEAVE
  68         SENF_PARSER_FIELD            ( interval,             UInt8Parser );  // 5 according to rfc3077
  69         SENF_PARSER_FIELD            ( sequence_number,      UInt16Parser );
  70         SENF_PARSER_PRIVATE_BITFIELD ( reserved,             3, unsigned );
  71         SENF_PARSER_BITFIELD         ( receive_capable_feed, 1, bool );      // 0=send only, 1=receive_capable_feed
  72         SENF_PARSER_BITFIELD_RO      ( ip_version,           4, unsigned );  // 4=IPv4, 6=IPv6
  73         SENF_PARSER_FIELD    ( tunnel_protocol,      UInt8Parser );
  74         /* Please consider the following comments on the implementation given in this class:
  75          * 1. you could think of simply using SENF_PARSER_PRIVATE_VARIANT and List / Vectorparser like this:
  76          * SENF_PARSER_PRIVATE_VARIANT  ( fbiplist,             ip_version,
  77          *                                                       (senf::VoidPacketParser) //ip_version=0
  78          *                                                       (senf::VoidPacketParser) //1
  79          *                                                       (senf::VoidPacketParser) //2
  80          *                                                       (senf::VoidPacketParser) //3
  81          *                                                       (senf::ListBParser< IPv4Packet, num_of_fbips>) //4
  82          *                                                       (senf::VoidPacketParser) //5
  83          *                                                       (senf::ListBParser< IPv6Packet, num_of_fbips>) ); //6
  84          * This can't work for two reasons:
  85          *      -SENF_PARSER_PRIVATE_VARIANT only accepts 6 templates in types but you have to start from 0.
  86          *      -you NEVER can use templated Parsers in these macros since the macro-preprocessor won't recognize the <> brackets and will
  87          *      interpret the ","
  88          *
  89          * The first problem is solved by using (actually inventing)  SENF_PARSER_VARIANT_TRANS which has the same limitations
  90          *      concerning the number of types but isn't limited to the values used. This is achieved by a translating function
  91          *      as you can see.
  92          * The second problem is solved by introducing Helper-Parser which cover both the list and the number field. By that no
  93          *      templates have to be used.
  94          */
  95
  96         struct ip_version_translator {
  97             static unsigned fromChooser(ip_version_t::value_type in) {
  98                 switch (in) {
  99                 case 4: return 0;
 100                 case 6: return 1;
 101                 }
 102                 return 1; //default. should rather throw an exception
 103             }
 104             static ip_version_t::value_type toChooser(unsigned in) {
 105                 switch (in) {
 106                 case 0: return 4;
 107                 case 1: return 6;
 108                 }
 109                 return 6; //default. should rather throw an exception
 110             }
 111         };
 112
 113         SENF_PARSER_VARIANT_TRANS    ( fbiplist,             ip_version, ip_version_translator,
 114                                                                  (senf::DTCPIPv4AddressListParser)        //IPv4
 115                                                                  (senf::DTCPIPv6AddressListParser) );     //IPv6
 116
 117         DTCPIPv4AddressListParser getIpv4AddressList () const { return fbiplist().get<0>(); }  // this is the absolute index
 118         DTCPIPv6AddressListParser getIpv6AddressList () const { return fbiplist().get<1>(); }
 119         void setIpVersion4() const { fbiplist().init<0>(); }
 120         void setIpVersion6() const { fbiplist().init<1>(); }
 121
 122         SENF_PARSER_FINALIZE(DTCPPacketParser);
 123     };
 124
 125     /** \brief DTCP packet
 126
 127         \par Packet type (typedef):
 128             \ref DTCPPacket
 129
 130         \par Fields:
 131             \ref DTCPPacketParser
 132
 133         \ingroup protocolbundle_mpegdvb
 134      */
 135     struct DTCPPacketType
 136         : public PacketTypeBase,
 137           public PacketTypeMixin<DTCPPacketType>
 138     {
 139         typedef PacketTypeMixin<DTCPPacketType> mixin;
 140         typedef ConcretePacket<DTCPPacketType> packet;
 141         typedef DTCPPacketParser parser;
 142
 143         using mixin::nextPacketRange;
 144         using mixin::init;
 145         using mixin::initSize;
 146
 147         static void dump(packet p, std::ostream & os);
 148     };
 149
 150     /** \brief DTCP packet typedef */
 151     typedef DTCPPacketType::packet DTCPPacket;
 152 }
 153
 154 #endif /*DTCPPACKET_HH_*/