senf/Packets/80211Bundle/RadiotapPacket.cc

   1 // $Id$
   2 //
   3 // Copyright (C) 2008
   4 // Fraunhofer Institute for Open Communication Systems (FOKUS)
   5 //
   6 // The contents of this file are subject to the Fraunhofer FOKUS Public License
   7 // Version 1.0 (the "License"); you may not use this file except in compliance
   8 // with the License. You may obtain a copy of the License at
   9 // http://senf.berlios.de/license.html
  10 //
  11 // The Fraunhofer FOKUS Public License Version 1.0 is based on,
  12 // but modifies the Mozilla Public License Version 1.1.
  13 // See the full license text for the amendments.
  14 //
  15 // Software distributed under the License is distributed on an "AS IS" basis,
  16 // WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
  17 // for the specific language governing rights and limitations under the License.
  18 //
  19 // The Original Code is Fraunhofer FOKUS code.
  20 //
  21 // The Initial Developer of the Original Code is Fraunhofer-Gesellschaft e.V.
  22 // (registered association), Hansastraße 27 c, 80686 Munich, Germany.
  23 // All Rights Reserved.
  24 //
  25 // Contributor(s):
  26 //   Stefan Bund <g0dil@berlios.de>
  27 //   Christian Niephaus <cni@berlios.de>
  28
  29
  30 // Definition of RadiotapPacket non-inline non-template functions
  31
  32 #include "RadiotapPacket.hh"
  33 //#include "RadiotapPacket.ih"
  34
  35 // Custom includes
  36 #include "WLANPacket.hh"
  37 #include <boost/io/ios_state.hpp>
  38 #include <memory.h>
  39
  40 extern "C" {
  41 #   include "radiotap/radiotap_iter.h"
  42 }
  43
  44 #define prefix_
  45 //-/////////////////////////////////////////////////////////////////////////////////////////////////
  46
  47 //-/////////////////////////////////////////////////////////////////////////////////////////////////
  48 // Offset table management
  49
  50 prefix_ senf::RadiotapPacketParser::OffsetTable &
  51 senf::RadiotapPacketParser::offsetTable(boost::uint32_t presentFlags)
  52 {
  53     typedef std::map<boost::uint32_t, OffsetTable> OffsetMap;
  54     static OffsetMap offsetMap;
  55
  56     OffsetMap::iterator i (offsetMap.find(presentFlags));
  57     if (i == offsetMap.end())
  58         i = offsetMap.insert(std::make_pair(presentFlags, OffsetTable())).first;
  59     return i->second;
  60 }
  61
  62 prefix_ void senf::RadiotapPacketParser::parseOffsetTable(boost::uint8_t * data, int maxLength,
  63                                                           OffsetTable & table)
  64 {
  65     struct ieee80211_radiotap_iterator iter;
  66     ieee80211_radiotap_iterator_init(&iter,
  67                                      (struct ieee80211_radiotap_header *)data,
  68                                      maxLength,
  69                                      0);
  70     unsigned size (8u);
  71     while (ieee80211_radiotap_iterator_next(&iter) == 0) {
  72         if (iter.is_radiotap_ns &&
  73             iter.this_arg_index <= int(RadiotapPacketParser::MAX_INDEX))
  74             table[iter.this_arg_index] = iter.this_arg - data;
  75         // We need to set size here in the loop since the iter fields are only valid
  76         // when at least one present bit is set ...
  77         size = iter.this_arg - data + iter.this_arg_size;
  78     }
  79     table[MAX_INDEX+1] = size;
  80 }
  81
  82 prefix_ void senf::RadiotapPacketParser::buildOffsetTable(boost::uint32_t presentFlags,
  83                                                           OffsetTable & table)
  84 {
  85     SENF_ASSERT(!(presentFlags & ( (1<<IEEE80211_RADIOTAP_RADIOTAP_NAMESPACE) |
  86                                    (1<<IEEE80211_RADIOTAP_VENDOR_NAMESPACE) |
  87                                    (1<<IEEE80211_RADIOTAP_EXT) )),
  88                 "Extended or vendor fields not supported");
  89
  90     struct ieee80211_radiotap_header header;
  91     memset(&header, 0, sizeof(header));
  92     // header.it_version = 0;
  93
  94     // Iterating this packet will generate invalid addresses but we don't care since neither
  95     // radiotap.c nor we will ever dereference those pointers, we just calculate the offsets.
  96     // This works, as long as we don't support extension headers ...
  97     header.it_len = 0xFFFF;
  98     // Note that all data in the header is little endian!
  99     header.it_present = htole32(presentFlags);
 100
 101     parseOffsetTable((boost::uint8_t*)&header, header.it_len, table);
 102 }
 103
 104 //-/////////////////////////////////////////////////////////////////////////////////////////////////
 105 // senf::RadiotapPacketParser
 106
 107 unsigned const senf::RadiotapPacketParser_Header::FIELD_SIZE[] = {
 108     8, 1, 1, 4, 2, 1, 1, 2, 2, 2, 1, 1, 1, 1, 2, 2, 1, 1 };
 109
 110 prefix_ senf::UInt32Parser senf::RadiotapPacketParser::init_fcs()
 111 {
 112     if (!has_fcs()) {
 113         protect(), data().insert(data().end(), 4u, 0u);
 114         init_flags().fcsAtEnd_() = true;
 115     }
 116     return fcs();
 117 }
 118
 119 prefix_ void senf::RadiotapPacketParser::disable_fcs()
 120 {
 121     if (has_fcs()) {
 122         validate(RadiotapPacketParser_Header::fixed_bytes+4);
 123         data().erase(data().end()-4, data().end());
 124         flags().fcsAtEnd_() = false;
 125     }
 126 }
 127
 128 prefix_ senf::RadiotapPacketParser::OffsetTable const &
 129 senf::RadiotapPacketParser::getTable(boost::uint32_t presentFlags)
 130     const
 131 {
 132     OffsetTable & table(offsetTable(presentFlags));
 133     if (! table[MAX_INDEX+1])
 134         buildOffsetTable(presentFlags, table);
 135     return table;
 136 }
 137
 138 prefix_ void senf::RadiotapPacketParser::insertRemoveBytes(unsigned from , unsigned to, int bytes)
 139 {
 140     data_iterator b (i() + from);
 141     data_iterator e (i() + to);
 142     if (bytes >= 0) {
 143         // Insert some bytes cleaning the old bytes to 0 first
 144         std::fill(b, e,  0u);
 145         if (bytes > 0)
 146             // need to protect the parser since data().insert() invalidates iterators
 147             protect(), data().insert(e, bytes, 0u);
 148     }
 149     else { // bytes < 0
 150         // Remove some bytes ...
 151         // remember: bytes is negative ...
 152         if (b < e + bytes)
 153             std::fill(b, e + bytes, 0u);
 154         data().erase(e + bytes, e);
 155     }
 156 }
 157
 158 prefix_ void senf::RadiotapPacketParser::updatePresentFlags(boost::uint32_t flags)
 159 {
 160     if (flags == presentFlags())
 161         return;
 162     validate(bytes());
 163
 164     OffsetTable const & oldTable (currentTable());
 165     OffsetTable const & newTable (getTable(flags));
 166     unsigned b (RadiotapPacketParser_Header::fixed_bytes);
 167     int cumulativeNewBytes (0);
 168
 169     for (unsigned index (0); index <= MAX_INDEX; ++index) {
 170         // Skip any unchanged fields
 171         for (; index <= MAX_INDEX+1
 172                  && ((oldTable[index] == 0 && newTable[index] == 0)
 173                      || (oldTable[index]+cumulativeNewBytes == newTable[index])); ++index)
 174             if (newTable[index] != 0)
 175                 b = newTable[index] + FIELD_SIZE[index];
 176         if (index > MAX_INDEX+1)
 177             break;
 178         // Now skip over all changed fields
 179         // (The condition index <= MAX_INDEX is not needed here since the last
 180         // table entry MAX_INDEX+1 is always != 0 in both tables)
 181         for (; ! (oldTable[index]!=0 && newTable[index]!=0); ++index) ;
 182         // index now either points to
 183         // a) an entry set in both tables
 184         // b) at the end of the table which contains the total length
 185         // (remember: the table has a size of MAX_INDEX+2 entries !!)
 186         // in both cases, the difference between the new and old size
 187         // is found from the difference between the old and the new table
 188         // entry
 189         int newBytes (newTable[index] - oldTable[index] - cumulativeNewBytes);
 190         insertRemoveBytes(b, oldTable[index] + cumulativeNewBytes, newBytes);
 191         cumulativeNewBytes += newBytes;
 192         b = newTable[index] + FIELD_SIZE[index];
 193     }
 194     length() += cumulativeNewBytes;
 195     presentFlags() = flags;
 196     currentTable_ = &newTable;
 197 }
 198
 199 //-/////////////////////////////////////////////////////////////////////////////////////////////////
 200 // senf::RadiotapPacketType
 201
 202 prefix_ void senf::RadiotapPacketType::dump(packet p, std::ostream & os)
 203 {
 204     boost::io::ios_all_saver ias(os);
 205     os << "Radiotap:\n"
 206        << senf::fieldName("version") << unsigned(p->version()) << '\n'
 207        << senf::fieldName("length")  << unsigned(p->length()) << '\n';
 208
 209 #   define FIELD(name, sign, desc)                                      \
 210         if (p->name ## Present())                                       \
 211             os << senf::fieldName(desc) << sign(p->name()) << '\n';
 212
 213 #   define ENTER(name)                                                  \
 214         if (p->name ## Present()) {                                     \
 215             packet::Parser::name ## _t subparser (p->name());
 216
 217 #   define SUBFIELD(name, sign, desc)                                   \
 218         os << senf::fieldName(desc) << sign(subparser.name()) << '\n';
 219
 220 #   define LEAVE()                                                      \
 221         }
 222
 223 #   define START_FLAGS(desc)                                            \
 224         os << senf::fieldName(desc);
 225
 226 #   define FLAG(name, desc)                                             \
 227         if (subparser.name()) os << desc " "
 228
 229 #   define END_FLAGS()                                                  \
 230         os << '\n';
 231
 232     FIELD           ( tsft,              boost::uint64_t, "MAC timestamp"        );
 233     ENTER           ( flags                                                      );
 234       START_FLAGS   (                                     "flags"                );
 235         FLAG        (     shortGI,                            "ShortGI"          );
 236         FLAG        (     badFCS,                             "BadFCS"           );
 237         FLAG        (     fcsAtEnd,                           "FCSatEnd"         );
 238         FLAG        (     fragmentation,                      "Frag"             );
 239         FLAG        (     wep,                                "WEP"              );
 240         FLAG        (     shortPreamble,                      "ShortPreamble"    );
 241         FLAG        (     cfp,                                "CFP"              );
 242       END_FLAGS     (                                                            );
 243     LEAVE           (                                                            );
 244     FIELD           ( rate,              unsigned,        "rate"                 );
 245     ENTER           ( channelOptions                                             );
 246       SUBFIELD      (     freq,          unsigned,        "channel frequency"    );
 247       START_FLAGS   (                                     "channel flags"        );
 248         FLAG        (     flag2ghz,                           "2GHz"             );
 249         FLAG        (     ofdm,                               "OFDM"             );
 250         FLAG        (     cck,                                "CCK"              );
 251         FLAG        (     turbo,                              "Turbo"            );
 252         FLAG        (     quarterRateChannel,                 "Rate/4"           );
 253         FLAG        (     halfRateChannel,                    "Rate/2"           );
 254         FLAG        (     gsm,                                "GSM"              );
 255         FLAG        (     staticTurbo,                        "StaticTurbo"      );
 256         FLAG        (     gfsk,                               "GFSK"             );
 257         FLAG        (     cckOfdm,                            "CCK+OFDM"         );
 258         FLAG        (     passive,                            "Passive"          );
 259         FLAG        (     flag5ghz,                           "5GHz"             );
 260       END_FLAGS     (                                                            );
 261     LEAVE           (                                                            );
 262     FIELD           ( fhss,              unsigned,        "FHSS"                 );
 263     FIELD           ( dbmAntennaSignal,  signed,          "antenna signal (dBm)" );
 264     FIELD           ( dbmAntennaNoise,   signed,          "antenna noise (dBm)"  );
 265     FIELD           ( lockQuality,       unsigned,        "lock quality"         );
 266     FIELD           ( txAttenuation,     unsigned,        "tx attenuation"       );
 267     FIELD           ( dbTxAttenuation,   unsigned,        "tx attenuation (dB)"  );
 268     FIELD           ( dbmTxAttenuation,  signed,          "tx attenuation (dBm)" );
 269     FIELD           ( antenna,           unsigned,        "antenna"              );
 270     FIELD           ( dbAntennaSignal,   unsigned,        "antenna signal (dB)"  );
 271     FIELD           ( dbAntennaNoise,    unsigned,        "antenna noise (dB)"   );
 272     ENTER           ( rxFlags                                                    );
 273       START_FLAGS   (                                     "rx flags"             );
 274         FLAG        (     badPlcp,                            "BadPLCP"          );
 275       END_FLAGS     (                                                            );
 276     LEAVE           (                                                            );
 277     ENTER           ( txFlags                                                    );
 278       START_FLAGS   (                                     "tx flags"             );
 279         FLAG        (     fail,                               "Fail"             );
 280         FLAG        (     txRts,                              "RTS"              );
 281         FLAG        (     txCts,                              "CTS"              );
 282       END_FLAGS     (                                                            );
 283     LEAVE           (                                                            );
 284     FIELD           ( rtsRetries,        unsigned,        "rts retries"          );
 285     FIELD           ( dataRetries,       unsigned,        "data retries"         );
 286
 287     if (p->flagsPresent() && p->flags().fcsAtEnd())
 288         os << senf::fieldName("fcs") << unsigned(p->fcs()) << '\n';
 289
 290 #   undef END_FLAGS
 291 #   undef FLAG
 292 #   undef START_FLAGS
 293 #   undef LEAVE
 294 #   undef SUBFIELD
 295 #   undef ENTER
 296 #   undef FIELD
 297 }
 298
 299 prefix_ void senf::RadiotapPacketType::init(packet p)
 300 {
 301     // ?? Why the heck do we need the +0? Otherwise we get an
 302     // 'undefined reference to 'RadiotapPacketParser_Header::fixed_bytes'
 303     p->length() << RadiotapPacketParser_Header::fixed_bytes+0;
 304 }
 305
 306 prefix_ senf::PacketInterpreterBase::factory_t senf::RadiotapPacketType::nextPacketType(packet p)
 307 {
 308     static factory_t frameTypeFactory[] = { WLANPacket_MgtFrame::factory(),
 309                                             WLANPacket_CtrlFrame::factory(),
 310                                             WLANPacket_DataFrame::factory(),
 311                                             no_factory() };
 312     return frameTypeFactory[p->frameType()];
 313 }
 314
 315 prefix_ senf::RadiotapPacketType::optional_range
 316 senf::RadiotapPacketType::nextPacketRange(packet const & p)
 317 {
 318     parser rtParser (p.parser());
 319     size_type h (senf::bytes(rtParser));
 320     size_type t (rtParser.flagsPresent() && rtParser.flags().fcsAtEnd() ? 4 : 0);
 321     return p.size() <= h+t
 322         ? no_range()
 323         : optional_range( range(p.data().begin() + h, p.data().end() - t) );
 324 }
 325
 326 //-/////////////////////////////////////////////////////////////////////////////////////////////////
 327 #undef prefix_
 328
 329 \f
 330 // Local Variables:
 331 // mode: c++
 332 // fill-column: 100
 333 // c-file-style: "senf"
 334 // indent-tabs-mode: nil
 335 // ispell-local-dictionary: "american"
 336 // compile-command: "scons -u test"
 337 // comment-column: 40
 338 // End: