senf/Packets/80211Bundle/RadiotapPacket.cc

   1 // $Id$
   2 //
   3 // Copyright (C) 2008
   4 // Fraunhofer Institute for Open Communication Systems (FOKUS)
   5 // Competence Center NETwork research (NET), St. Augustin, GERMANY
   6 //     Christian Niephaus <cni@berlios.de>
   7 //     Stefan Bund <g0dil@berlios.de>
   8 //
   9 // This program is free software; you can redistribute it and/or modify
  10 // it under the terms of the GNU General Public License as published by
  11 // the Free Software Foundation; either version 2 of the License, or
  12 // (at your option) any later version.
  13 //
  14 // This program is distributed in the hope that it will be useful,
  15 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17 // GNU General Public License for more details.
  18 //
  19 // You should have received a copy of the GNU General Public License
  20 // along with this program; if not, write to the
  21 // Free Software Foundation, Inc.,
  22 // 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  23
  24 // Definition of RadiotapPacket non-inline non-template functions
  25
  26 #include "RadiotapPacket.hh"
  27 //#include "RadiotapPacket.ih"
  28
  29 // Custom includes
  30 #include "WLANPacket.hh"
  31 #include <boost/io/ios_state.hpp>
  32 #include <memory.h>
  33
  34 extern "C" {
  35 #   include "radiotap/radiotap_iter.h"
  36 }
  37
  38 #define prefix_
  39 //-/////////////////////////////////////////////////////////////////////////////////////////////////
  40
  41 //-/////////////////////////////////////////////////////////////////////////////////////////////////
  42 // Offset table management
  43
  44 prefix_ senf::RadiotapPacketParser::OffsetTable &
  45 senf::RadiotapPacketParser::offsetTable(boost::uint32_t presentFlags)
  46 {
  47     typedef std::map<boost::uint32_t, OffsetTable> OffsetMap;
  48     static OffsetMap offsetMap;
  49
  50     OffsetMap::iterator i (offsetMap.find(presentFlags));
  51     if (i == offsetMap.end())
  52         i = offsetMap.insert(std::make_pair(presentFlags, OffsetTable())).first;
  53     return i->second;
  54 }
  55
  56 prefix_ void senf::RadiotapPacketParser::parseOffsetTable(boost::uint8_t * data, int maxLength,
  57                                                           OffsetTable & table)
  58 {
  59     struct ieee80211_radiotap_iterator iter;
  60     ieee80211_radiotap_iterator_init(&iter,
  61                                      (struct ieee80211_radiotap_header *)data,
  62                                      maxLength,
  63                                      0);
  64     unsigned size (8u);
  65     while (ieee80211_radiotap_iterator_next(&iter) == 0) {
  66         if (iter.is_radiotap_ns &&
  67             iter.this_arg_index <= int(senf::RadiotapPacketParser::MAX_INDEX))
  68             table[iter.this_arg_index] = iter.this_arg - data;
  69         // We need to set size here in the loop since the iter fields are only valid
  70         // when at least one present bit is set ...
  71         size = iter.this_arg - data + iter.this_arg_size;
  72     }
  73     table[MAX_INDEX+1] = size;
  74 }
  75
  76 prefix_ void senf::RadiotapPacketParser::buildOffsetTable(boost::uint32_t presentFlags,
  77                                                           OffsetTable & table)
  78 {
  79     SENF_ASSERT(!(presentFlags & ( (1<<IEEE80211_RADIOTAP_RADIOTAP_NAMESPACE) |
  80                                    (1<<IEEE80211_RADIOTAP_VENDOR_NAMESPACE) |
  81                                    (1<<IEEE80211_RADIOTAP_EXT) )),
  82                 "Extended or vendor fields not supported");
  83
  84     struct ieee80211_radiotap_header header;
  85     memset(&header, 0, sizeof(header));
  86     // header.it_version = 0;
  87
  88     // Iterating this packet will generate invalid addresses but we don't care since neither
  89     // radiotap.c nor we will ever dereference those pointers, we just calculate the offsets.
  90     // This works, as long as we don't support extension headers ...
  91     header.it_len = 0xFFFF;
  92     header.it_present = presentFlags;
  93
  94     parseOffsetTable((boost::uint8_t*)&header, header.it_len, table);
  95 }
  96
  97 //-/////////////////////////////////////////////////////////////////////////////////////////////////
  98 // senf::RadiotapPacketParser
  99
 100 unsigned const senf::RadiotapPacketParser_Header::FIELD_SIZE[] = {
 101     8, 1, 1, 4, 2, 1, 1, 2, 2, 2, 1, 1, 1, 1, 2, 2, 1, 1 };
 102
 103 prefix_ senf::UInt32Parser senf::RadiotapPacketParser::init_fcs()
 104 {
 105     if (!has_fcs()) {
 106         protect(), data().insert(data().end(), 4u, 0u);
 107         init_flags().fcsAtEnd_() = true;
 108     }
 109     return fcs();
 110 }
 111
 112 prefix_ void senf::RadiotapPacketParser::disable_fcs()
 113 {
 114     if (has_fcs()) {
 115         validate(RadiotapPacketParser_Header::fixed_bytes+4);
 116         data().erase(data().end()-4, data().end());
 117         flags().fcsAtEnd_() = false;
 118     }
 119 }
 120
 121 prefix_ senf::RadiotapPacketParser::OffsetTable const &
 122 senf::RadiotapPacketParser::getTable(boost::uint32_t presentFlags)
 123     const
 124 {
 125     OffsetTable & table(offsetTable(presentFlags));
 126     if (! table[MAX_INDEX+1])
 127         buildOffsetTable(presentFlags, table);
 128     return table;
 129 }
 130
 131 prefix_ void senf::RadiotapPacketParser::insertRemoveBytes(unsigned from , unsigned to, int bytes)
 132 {
 133     data_iterator b (i() + from);
 134     data_iterator e (i() + to);
 135     if (bytes >= 0) {
 136         // Insert some bytes cleaning the old bytes to 0 first
 137         std::fill(b, e,  0u);
 138         if (bytes > 0)
 139             // need to protect the parser since data().insert() invalidates iterators
 140             protect(), data().insert(e, bytes, 0u);
 141     }
 142     else { // bytes < 0
 143         // Remove some bytes ...
 144         // remember: bytes is negative ...
 145         if (b < e + bytes)
 146             std::fill(b, e + bytes, 0u);
 147         data().erase(e + bytes, e);
 148     }
 149 }
 150
 151 prefix_ void senf::RadiotapPacketParser::updatePresentFlags(boost::uint32_t flags)
 152 {
 153     if (flags == presentFlags())
 154         return;
 155     validate(bytes());
 156
 157     OffsetTable const & oldTable (currentTable());
 158     OffsetTable const & newTable (getTable(flags));
 159     unsigned b (RadiotapPacketParser_Header::fixed_bytes);
 160     int cumulativeNewBytes (0);
 161
 162     for (unsigned index (0); index <= MAX_INDEX; ++index) {
 163         // Skip any unchanged fields
 164         for (; index <= MAX_INDEX+1
 165                  && ((oldTable[index] == 0 && newTable[index] == 0)
 166                      || (oldTable[index]+cumulativeNewBytes == newTable[index])); ++index)
 167             if (newTable[index] != 0)
 168                 b = newTable[index] + FIELD_SIZE[index];
 169         if (index > MAX_INDEX+1)
 170             break;
 171         // Now skip over all changed fields
 172         // (The condition index <= MAX_INDEX is not needed here since the last
 173         // table entry MAX_INDEX+1 is always != 0 in both tables)
 174         for (; ! (oldTable[index]!=0 && newTable[index]!=0); ++index) ;
 175         // index now either points to
 176         // a) an entry set in both tables
 177         // b) at the end of the table which contains the total length
 178         // (remember: the table has a size of MAX_INDEX+2 entries !!)
 179         // in both cases, the difference between the new and old size
 180         // is found from the difference between the old and the new table
 181         // entry
 182         int newBytes (newTable[index] - oldTable[index] - cumulativeNewBytes);
 183         insertRemoveBytes(b, oldTable[index] + cumulativeNewBytes, newBytes);
 184         cumulativeNewBytes += newBytes;
 185         b = newTable[index] + FIELD_SIZE[index];
 186     }
 187     length() += cumulativeNewBytes;
 188     presentFlags() = flags;
 189     currentTable_ = &newTable;
 190 }
 191
 192 //-/////////////////////////////////////////////////////////////////////////////////////////////////
 193 // senf::RadiotapPacketType
 194
 195 prefix_ void senf::RadiotapPacketType::dump(packet p, std::ostream &os)
 196 {
 197     boost::io::ios_all_saver ias(os);
 198     os << "Radiotap:\n"
 199        << senf::fieldName("version") << unsigned(p->version()) << '\n'
 200        << senf::fieldName("length")  << unsigned(p->length()) << '\n';
 201
 202 #   define FIELD(name, sign, desc)                                      \
 203         if (p->name ## Present())                                       \
 204             os << senf::fieldName(desc) << sign(p->name()) << '\n';
 205
 206 #   define ENTER(name)                                                  \
 207         if (p->name ## Present()) {                                     \
 208             packet::Parser::name ## _t subparser (p->name());
 209
 210 #   define SUBFIELD(name, sign, desc)                                   \
 211         os << senf::fieldName(desc) << sign(subparser.name()) << '\n';
 212
 213 #   define LEAVE()                                                      \
 214         }
 215
 216 #   define START_FLAGS(desc)                                            \
 217         os << senf::fieldName(desc);
 218
 219 #   define FLAG(name, desc)                                             \
 220         if (subparser.name()) os << desc " "
 221
 222 #   define END_FLAGS()                                                  \
 223         os << '\n';
 224
 225     FIELD           ( tsft,              boost::uint64_t, "MAC timestamp"        );
 226     ENTER           ( flags                                                      );
 227       START_FLAGS   (                                     "flags"                );
 228         FLAG        (     shortGI,                            "ShortGI"          );
 229         FLAG        (     badFCS,                             "BadFCS"           );
 230         FLAG        (     fcsAtEnd,                           "FCSatEnd"         );
 231         FLAG        (     fragmentation,                      "Frag"             );
 232         FLAG        (     wep,                                "WEP"              );
 233         FLAG        (     shortPreamble,                      "ShortPreamble"    );
 234         FLAG        (     cfp,                                "CFP"              );
 235       END_FLAGS     (                                                            );
 236     LEAVE           (                                                            );
 237     FIELD           ( rate,              unsigned,        "rate"                 );
 238     ENTER           ( channelOptions                                             );
 239       SUBFIELD      (     freq,          unsigned,        "channel frequency"    );
 240       START_FLAGS   (                                     "channel flags"        );
 241         FLAG        (     flag2ghz,                           "2GHz"             );
 242         FLAG        (     ofdm,                               "OFDM"             );
 243         FLAG        (     cck,                                "CCK"              );
 244         FLAG        (     turbo,                              "Turbo"            );
 245         FLAG        (     quarterRateChannel,                 "Rate/4"           );
 246         FLAG        (     halfRateChannel,                    "Rate/2"           );
 247         FLAG        (     gsm,                                "GSM"              );
 248         FLAG        (     staticTurbo,                        "StaticTurbo"      );
 249         FLAG        (     gfsk,                               "GFSK"             );
 250         FLAG        (     cckOfdm,                            "CCK+OFDM"         );
 251         FLAG        (     passive,                            "Passive"          );
 252         FLAG        (     flag5ghz,                           "5GHz"             );
 253       END_FLAGS     (                                                            );
 254     LEAVE           (                                                            );
 255     FIELD           ( fhss,              unsigned,        "FHSS"                 );
 256     FIELD           ( dbmAntennaSignal,  signed,          "antenna signal (dBm)" );
 257     FIELD           ( dbmAntennaNoise,   signed,          "antenna noise (dBm)"  );
 258     FIELD           ( lockQuality,       unsigned,        "lock quality"         );
 259     FIELD           ( txAttenuation,     unsigned,        "tx attenuation"       );
 260     FIELD           ( dbTxAttenuation,   unsigned,        "tx attenuation (dB)"  );
 261     FIELD           ( dbmTxAttenuation,  signed,          "tx attenuation (dBm)" );
 262     FIELD           ( antenna,           unsigned,        "antenna"              );
 263     FIELD           ( dbAntennaSignal,   unsigned,        "antenna signal (dB)"  );
 264     FIELD           ( dbAntennaNoise,    unsigned,        "antenna noise (dB)"   );
 265     ENTER           ( rxFlags                                                    );
 266       START_FLAGS   (                                     "rx flags"             );
 267         FLAG        (     badPlcp,                            "BadPLCP"          );
 268       END_FLAGS     (                                                            );
 269     LEAVE           (                                                            );
 270     ENTER           ( txFlags                                                    );
 271       START_FLAGS   (                                     "tx flags"             );
 272         FLAG        (     fail,                               "Fail"             );
 273         FLAG        (     txRts,                              "RTS"              );
 274         FLAG        (     txCts,                              "CTS"              );
 275       END_FLAGS     (                                                            );
 276     LEAVE           (                                                            );
 277     FIELD           ( rtsRetries,        unsigned,        "rts retries"          );
 278     FIELD           ( dataRetries,       unsigned,        "data retries"         );
 279
 280     if (p->flagsPresent() && p->flags().fcsAtEnd())
 281         os << senf::fieldName("fcs") << unsigned(p->fcs()) << '\n';
 282
 283 #   undef END_FLAGS
 284 #   undef FLAG
 285 #   undef START_FLAGS
 286 #   undef LEAVE
 287 #   undef SUBFIELD
 288 #   undef ENTER
 289 #   undef FIELD
 290 }
 291
 292 prefix_ void senf::RadiotapPacketType::init(packet p)
 293 {
 294     // ?? Why the heck do we need the +0? Otherwise we get an
 295     // 'undefined reference to 'RadiotapPacketParser_Header::fixed_bytes'
 296     p->length() << RadiotapPacketParser_Header::fixed_bytes+0;
 297 }
 298
 299 prefix_ senf::PacketInterpreterBase::factory_t senf::RadiotapPacketType::nextPacketType(packet p)
 300 {
 301     static factory_t frameTypeFactory[] = { WLANPacket_MgtFrame::factory(),
 302                                             WLANPacket_CtrlFrame::factory(),
 303                                             WLANPacket_DataFrame::factory(),
 304                                             no_factory() };
 305     return frameTypeFactory[p->frameType()];
 306 }
 307
 308 prefix_ senf::RadiotapPacketType::optional_range
 309 senf::RadiotapPacketType::nextPacketRange(packet p)
 310 {
 311     parser rtParser (p.parser());
 312     size_type h (senf::bytes(rtParser));
 313     size_type t (rtParser.flagsPresent() && rtParser.flags().fcsAtEnd() ? 4 : 0);
 314     return p.size() <= h+t
 315         ? no_range()
 316         : optional_range( range(p.data().begin() + h, p.data().end() - t) );
 317 }
 318
 319 //-/////////////////////////////////////////////////////////////////////////////////////////////////
 320 #undef prefix_
 321
 322 \f
 323 // Local Variables:
 324 // mode: c++
 325 // fill-column: 100
 326 // c-file-style: "senf"
 327 // indent-tabs-mode: nil
 328 // ispell-local-dictionary: "american"
 329 // compile-command: "scons -u test"
 330 // comment-column: 40
 331 // End: