include/net/ieee80211_radiotap.h

   1 /* $FreeBSD: src/sys/net80211/ieee80211_radiotap.h,v 1.5 2005/01/22 20:12:05 sam Exp $ */
   2 /* $NetBSD: ieee80211_radiotap.h,v 1.11 2005/06/22 06:16:02 dyoung Exp $ */
   3
   4 /*-
   5  * Copyright (c) 2003, 2004 David Young.  All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. The name of David Young may not be used to endorse or promote
  16  *    products derived from this software without specific prior
  17  *    written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY DAVID YOUNG ``AS IS'' AND ANY
  20  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
  21  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
  22  * PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL DAVID
  23  * YOUNG BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  24  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
  25  * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  26  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  27  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  28  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
  30  * OF SUCH DAMAGE.
  31  */
  32
  33 /*
  34  * Modifications to fit into the linux IEEE 802.11 stack,
  35  * Mike Kershaw (dragorn@kismetwireless.net)
  36  */
  37
  38 #ifndef IEEE80211RADIOTAP_H
  39 #define IEEE80211RADIOTAP_H
  40
  41 #include <linux/if_ether.h>
  42 #include <linux/kernel.h>
  43
  44 /* Radiotap header version (from official NetBSD feed) */
  45 #define IEEE80211RADIOTAP_VERSION       "1.5"
  46 /* Base version of the radiotap packet header data */
  47 #define PKTHDR_RADIOTAP_VERSION         0
  48
  49 /* A generic radio capture format is desirable. There is one for
  50  * Linux, but it is neither rigidly defined (there were not even
  51  * units given for some fields) nor easily extensible.
  52  *
  53  * I suggest the following extensible radio capture format. It is
  54  * based on a bitmap indicating which fields are present.
  55  *
  56  * I am trying to describe precisely what the application programmer
  57  * should expect in the following, and for that reason I tell the
  58  * units and origin of each measurement (where it applies), or else I
  59  * use sufficiently weaselly language ("is a monotonically nondecreasing
  60  * function of...") that I cannot set false expectations for lawyerly
  61  * readers.
  62  */
  63
  64 /* XXX tcpdump/libpcap do not tolerate variable-length headers,
  65  * yet, so we pad every radiotap header to 64 bytes. Ugh.
  66  */
  67 #define IEEE80211_RADIOTAP_HDRLEN       64
  68
  69 /* The radio capture header precedes the 802.11 header. */
  70 struct ieee80211_radiotap_header {
  71         u8 it_version;          /* Version 0. Only increases
  72                                  * for drastic changes,
  73                                  * introduction of compatible
  74                                  * new fields does not count.
  75                                  */
  76         u8 it_pad;
  77         u16 it_len;             /* length of the whole
  78                                  * header in bytes, including
  79                                  * it_version, it_pad,
  80                                  * it_len, and data fields.
  81                                  */
  82         u32 it_present;         /* A bitmap telling which
  83                                  * fields are present. Set bit 31
  84                                  * (0x80000000) to extend the
  85                                  * bitmap by another 32 bits.
  86                                  * Additional extensions are made
  87                                  * by setting bit 31.
  88                                  */
  89 };
  90
  91 /* Name                                 Data type       Units
  92  * ----                                 ---------       -----
  93  *
  94  * IEEE80211_RADIOTAP_TSFT              u64       microseconds
  95  *
  96  *      Value in microseconds of the MAC's 64-bit 802.11 Time
  97  *      Synchronization Function timer when the first bit of the
  98  *      MPDU arrived at the MAC. For received frames, only.
  99  *
 100  * IEEE80211_RADIOTAP_CHANNEL           2 x u16   MHz, bitmap
 101  *
 102  *      Tx/Rx frequency in MHz, followed by flags (see below).
 103  *
 104  * IEEE80211_RADIOTAP_FHSS              u16       see below
 105  *
 106  *      For frequency-hopping radios, the hop set (first byte)
 107  *      and pattern (second byte).
 108  *
 109  * IEEE80211_RADIOTAP_RATE              u8        500kb/s
 110  *
 111  *      Tx/Rx data rate
 112  *
 113  * IEEE80211_RADIOTAP_DBM_ANTSIGNAL     int8_t          decibels from
 114  *                                                      one milliwatt (dBm)
 115  *
 116  *      RF signal power at the antenna, decibel difference from
 117  *      one milliwatt.
 118  *
 119  * IEEE80211_RADIOTAP_DBM_ANTNOISE      int8_t          decibels from
 120  *                                                      one milliwatt (dBm)
 121  *
 122  *      RF noise power at the antenna, decibel difference from one
 123  *      milliwatt.
 124  *
 125  * IEEE80211_RADIOTAP_DB_ANTSIGNAL      u8        decibel (dB)
 126  *
 127  *      RF signal power at the antenna, decibel difference from an
 128  *      arbitrary, fixed reference.
 129  *
 130  * IEEE80211_RADIOTAP_DB_ANTNOISE       u8        decibel (dB)
 131  *
 132  *      RF noise power at the antenna, decibel difference from an
 133  *      arbitrary, fixed reference point.
 134  *
 135  * IEEE80211_RADIOTAP_LOCK_QUALITY      u16       unitless
 136  *
 137  *      Quality of Barker code lock. Unitless. Monotonically
 138  *      nondecreasing with "better" lock strength. Called "Signal
 139  *      Quality" in datasheets.  (Is there a standard way to measure
 140  *      this?)
 141  *
 142  * IEEE80211_RADIOTAP_TX_ATTENUATION    u16       unitless
 143  *
 144  *      Transmit power expressed as unitless distance from max
 145  *      power set at factory calibration.  0 is max power.
 146  *      Monotonically nondecreasing with lower power levels.
 147  *
 148  * IEEE80211_RADIOTAP_DB_TX_ATTENUATION u16       decibels (dB)
 149  *
 150  *      Transmit power expressed as decibel distance from max power
 151  *      set at factory calibration.  0 is max power.  Monotonically
 152  *      nondecreasing with lower power levels.
 153  *
 154  * IEEE80211_RADIOTAP_DBM_TX_POWER      int8_t          decibels from
 155  *                                                      one milliwatt (dBm)
 156  *
 157  *      Transmit power expressed as dBm (decibels from a 1 milliwatt
 158  *      reference). This is the absolute power level measured at
 159  *      the antenna port.
 160  *
 161  * IEEE80211_RADIOTAP_FLAGS             u8        bitmap
 162  *
 163  *      Properties of transmitted and received frames. See flags
 164  *      defined below.
 165  *
 166  * IEEE80211_RADIOTAP_ANTENNA           u8        antenna index
 167  *
 168  *      Unitless indication of the Rx/Tx antenna for this packet.
 169  *      The first antenna is antenna 0.
 170  *
 171  * IEEE80211_RADIOTAP_FCS               u32       data
 172  *
 173  *      FCS from frame in network byte order.
 174  */
 175 enum ieee80211_radiotap_type {
 176         IEEE80211_RADIOTAP_TSFT = 0,
 177         IEEE80211_RADIOTAP_FLAGS = 1,
 178         IEEE80211_RADIOTAP_RATE = 2,
 179         IEEE80211_RADIOTAP_CHANNEL = 3,
 180         IEEE80211_RADIOTAP_FHSS = 4,
 181         IEEE80211_RADIOTAP_DBM_ANTSIGNAL = 5,
 182         IEEE80211_RADIOTAP_DBM_ANTNOISE = 6,
 183         IEEE80211_RADIOTAP_LOCK_QUALITY = 7,
 184         IEEE80211_RADIOTAP_TX_ATTENUATION = 8,
 185         IEEE80211_RADIOTAP_DB_TX_ATTENUATION = 9,
 186         IEEE80211_RADIOTAP_DBM_TX_POWER = 10,
 187         IEEE80211_RADIOTAP_ANTENNA = 11,
 188         IEEE80211_RADIOTAP_DB_ANTSIGNAL = 12,
 189         IEEE80211_RADIOTAP_DB_ANTNOISE = 13,
 190         IEEE80211_RADIOTAP_EXT = 31,
 191 };
 192
 193 /* Channel flags. */
 194 #define IEEE80211_CHAN_TURBO    0x0010  /* Turbo channel */
 195 #define IEEE80211_CHAN_CCK      0x0020  /* CCK channel */
 196 #define IEEE80211_CHAN_OFDM     0x0040  /* OFDM channel */
 197 #define IEEE80211_CHAN_2GHZ     0x0080  /* 2 GHz spectrum channel. */
 198 #define IEEE80211_CHAN_5GHZ     0x0100  /* 5 GHz spectrum channel */
 199 #define IEEE80211_CHAN_PASSIVE  0x0200  /* Only passive scan allowed */
 200 #define IEEE80211_CHAN_DYN      0x0400  /* Dynamic CCK-OFDM channel */
 201 #define IEEE80211_CHAN_GFSK     0x0800  /* GFSK channel (FHSS PHY) */
 202
 203 /* For IEEE80211_RADIOTAP_FLAGS */
 204 #define IEEE80211_RADIOTAP_F_CFP        0x01    /* sent/received
 205                                                  * during CFP
 206                                                  */
 207 #define IEEE80211_RADIOTAP_F_SHORTPRE   0x02    /* sent/received
 208                                                  * with short
 209                                                  * preamble
 210                                                  */
 211 #define IEEE80211_RADIOTAP_F_WEP        0x04    /* sent/received
 212                                                  * with WEP encryption
 213                                                  */
 214 #define IEEE80211_RADIOTAP_F_FRAG       0x08    /* sent/received
 215                                                  * with fragmentation
 216                                                  */
 217 #define IEEE80211_RADIOTAP_F_FCS        0x10    /* frame includes FCS */
 218 #define IEEE80211_RADIOTAP_F_DATAPAD    0x20    /* frame has padding between
 219                                                  * 802.11 header and payload
 220                                                  * (to 32-bit boundary)
 221                                                  */
 222
 223 /* Ugly macro to convert literal channel numbers into their mhz equivalents
 224  * There are certianly some conditions that will break this (like feeding it '30')
 225  * but they shouldn't arise since nothing talks on channel 30. */
 226 #define ieee80211chan2mhz(x) \
 227         (((x) <= 14) ? \
 228         (((x) == 14) ? 2484 : ((x) * 5) + 2407) : \
 229         ((x) + 1000) * 5)
 230
 231 #endif                          /* IEEE80211_RADIOTAP_H */