X-Git-Url: http://g0dil.de/git?a=blobdiff_plain;f=Packets%2F80211Bundle%2FRadiotapPacket.hh;h=ebea56717b765a028127f955395526bdc58721d4;hb=d498c7507e2eaa191e859ae525df97dc257e0d7a;hp=48d020bb19735f8bf3514d27bdc4270ed0cffc9d;hpb=703dda9bbad122844e213475b7a4c0ce1759b65f;p=senf.git

diff --git a/Packets/80211Bundle/RadiotapPacket.hh b/Packets/80211Bundle/RadiotapPacket.hh
index 48d020b..ebea567 100644
--- a/Packets/80211Bundle/RadiotapPacket.hh
+++ b/Packets/80211Bundle/RadiotapPacket.hh
@@ -21,9 +21,7 @@
 // 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 
 /** \file
-    \brief Radiotap header \n
-        <b>Radiotap uses least significant bit byte order</b>
-    */
+    \brief Radiotap header */
 
 #ifndef HH_SENF_Packets_80211Bundle_RadiotapPacket_
 #define HH_SENF_Packets_80211Bundle_RadiotapPacket_ 1
@@ -34,10 +32,10 @@ namespace senf
 {
 
     /** \brief Parse Flag field in Radiotap header
-     * <b>Re-ordering of bits due to LSB byte order</b>
 
+        <b>Re-ordering of bits due to LSB byte order</b>
      */
-    struct RadiotapPacketParser_Flags : public senf::PacketParserBase
+    struct RadiotapPacketParser_Flags : public PacketParserBase
     {
     #   include SENF_FIXED_PARSER()
 
@@ -57,7 +55,7 @@ namespace senf
 
         <b>Re-ordering of bits due to LSB byte order</b>
      */
-    struct RadiotapPacketParser_ChannelOptions : public senf::PacketParserBase
+    struct RadiotapPacketParser_ChannelOptions : public PacketParserBase
     {
     #   include SENF_FIXED_PARSER()
 
@@ -84,11 +82,20 @@ namespace senf
 
         Parser implementing the Radiotap header
 
+        Radiotap requires that all fields in the radiotap header
+        are aligned to natural boundaries. For radiotap,
+        that means all 8-, 16-, 32-, and 64-bit fields
+        must begin on 8-, 16-, 32-, and 64-bit boundaries, respectively.
+        In this way, generators and parsers can avoid unaligned
+        accesses to radiotap capture fields. Radiotap-compliant
+        generators must insert padding before a capture field
+        to ensure its natural alignment.
+
         \see <a href="http://www.radiotap.org">Radiotap.org</a>
 
         \todo extended present field (bit 31 of present field is set)
     */
-    struct RadiotapPacketParser : public senf::PacketParserBase
+    struct RadiotapPacketParser : public PacketParserBase
     {
     #   include SENF_PARSER()
 
@@ -112,7 +119,8 @@ namespace senf
         SENF_PARSER_BITFIELD_RO ( ratePresent,             1, bool );
         SENF_PARSER_BITFIELD_RO ( flagsPresent,            1, bool );
         SENF_PARSER_BITFIELD_RO ( tsftPresent,             1, bool );
-        SENF_PARSER_SKIP_BITS   ( 2                                ); //currently unused bits
+        SENF_PARSER_SKIP_BITS   ( 1                                ); //currently unused bits
+        SENF_PARSER_BITFIELD_RO ( fcsPresent,              1, bool );
         SENF_PARSER_BITFIELD_RO ( dbAntennaNoisePresent,   1, bool );
         SENF_PARSER_BITFIELD_RO ( dbAntennaSignalPresent,  1, bool );
         SENF_PARSER_BITFIELD_RO ( antennaPresent,          1, bool );
@@ -127,30 +135,49 @@ namespace senf
         /*
          * Radiotap data
          * parsing data according to present flags
+         *
+         * PARSER_SKIP required to skip correct length of padding bits
          */
+
+        /* macro to create required variant parser */
         #define OPTIONAL_FIELD(name, parser) SENF_PARSER_VARIANT \
             ( name##_, name##Present, \
               ( novalue( disable_##name, VoidPacketParser )) \
-              (      id( name,           parser           )) );
-
-        OPTIONAL_FIELD ( tsft,             UInt64LSBParser                     );
-        OPTIONAL_FIELD ( flags,            RadiotapPacketParser_Flags          );
-        OPTIONAL_FIELD ( rate,             UInt8Parser                         );
-        OPTIONAL_FIELD ( channelOptions,   RadiotapPacketParser_ChannelOptions );
-        OPTIONAL_FIELD ( fhss,             UInt16LSBParser                     );
-        OPTIONAL_FIELD ( dbmAntennaSignal, Int8Parser                          );
-        OPTIONAL_FIELD ( dbmAntennaNoise,  Int8Parser                          );
-        OPTIONAL_FIELD ( txAttenuation,    UInt16LSBParser                     );
-        OPTIONAL_FIELD ( dbTxAttenuation,  UInt16LSBParser                     );
-        OPTIONAL_FIELD ( antenna,          UInt8Parser                         );
-        OPTIONAL_FIELD ( dbAntennaSignal,  UInt8Parser                         );
-        OPTIONAL_FIELD ( dbAntennaNoise,   UInt8Parser                         );
+              (      id( name,           parser           )) )
+
+        /* macro to create padding parser */
+        #define SKIP_OPTIONAL_PADDING(cond, parser, size) \
+            SENF_PARSER_SKIP( \
+                    (cond ? (size - (parser##__offset() + \
+                            senf::bytes(parser##_())) % size) % size : 0) , 0  );
+
+        OPTIONAL_FIELD        ( tsft,                     UInt64LSBParser                     );
+        OPTIONAL_FIELD        ( flags,                    RadiotapPacketParser_Flags          ); //<pkgdraw: size=8
+        OPTIONAL_FIELD        ( rate,                     UInt8Parser                         );
+        SKIP_OPTIONAL_PADDING ( channelOptionsPresent(),  rate, 2                             );
+        OPTIONAL_FIELD        ( channelOptions,           RadiotapPacketParser_ChannelOptions ); //<pkgdraw: size=32
+        SKIP_OPTIONAL_PADDING ( fhssPresent(),            channelOptions, 2                   );
+        OPTIONAL_FIELD        ( fhss,                     UInt16LSBParser                     );
+        OPTIONAL_FIELD        ( dbmAntennaSignal,         Int8Parser                          );
+        OPTIONAL_FIELD        ( dbmAntennaNoise,          Int8Parser                          );
+        SKIP_OPTIONAL_PADDING ( lockQualityPresent(),     dbmAntennaNoise, 2                  );
+        OPTIONAL_FIELD        ( lockQuality,              UInt16LSBParser                     );
+        SKIP_OPTIONAL_PADDING ( txAttenuationPresent(),   lockQuality, 2                      );
+        OPTIONAL_FIELD        ( txAttenuation,            UInt16LSBParser                     );
+        SKIP_OPTIONAL_PADDING ( dbTxAttenuationPresent(), txAttenuation, 2                    );
+        OPTIONAL_FIELD        ( dbTxAttenuation,          UInt16LSBParser                     );
+        OPTIONAL_FIELD        ( dbmTxAttenuation,         Int8Parser                          );
+        OPTIONAL_FIELD        ( antenna,                  UInt8Parser                         );
+        OPTIONAL_FIELD        ( dbAntennaSignal,          UInt8Parser                         );
+        OPTIONAL_FIELD        ( dbAntennaNoise,           UInt8Parser                         );
+        SKIP_OPTIONAL_PADDING ( fcsPresent(),             dbAntennaNoise, 4                   );
+        OPTIONAL_FIELD        ( fcs,                      UInt32Parser                        );
 
         SENF_PARSER_INIT() {
             version() = 0;
         }
 
-        SENF_PARSER_FINALIZE(RadiotapPacketParser);
+        SENF_PARSER_FINALIZE( RadiotapPacketParser );
     };
 
     /** \brief Radiotap packet
@@ -160,16 +187,19 @@ namespace senf
 
         \par Fields:
             \ref RadiotapPacketParser
-
+            \image html RadiotapPacket.png
+        
+        \see http://www.radiotap.org/
+        
         \ingroup protocolbundle_80211
      */
     struct RadiotapPacketType
-        : public senf::PacketTypeBase,
-          public senf::PacketTypeMixin<RadiotapPacketType>
+        : public PacketTypeBase,
+          public PacketTypeMixin<RadiotapPacketType>
     {
-        typedef senf::PacketTypeMixin<RadiotapPacketType> mixin;
-        typedef senf::ConcretePacket<RadiotapPacketType> packet;
-        typedef senf::RadiotapPacketParser parser;
+        typedef PacketTypeMixin<RadiotapPacketType> mixin;
+        typedef ConcretePacket<RadiotapPacketType> packet;
+        typedef RadiotapPacketParser parser;
 
         using mixin::nextPacketRange;
         using mixin::init;
@@ -177,9 +207,10 @@ namespace senf
 
         static void dump(packet p, std::ostream &os);
         static void finalize(packet p);
+        static factory_t nextPacketType(packet p);
     };
 
-    typedef senf::ConcretePacket<RadiotapPacketType> RadiotapPacket;
+    typedef ConcretePacket<RadiotapPacketType> RadiotapPacket;
 }
 
 #endif