Home | History | Annotate | Download | only in tcpdump
      1 /* $FreeBSD: src/sys/net80211/ieee80211_radiotap.h,v 1.5 2005/01/22 20:12:05 sam Exp $ */
      2 /* $NetBSD: ieee802_11_radio.h,v 1.2 2006/02/26 03:04:03 dyoung Exp $ */
      3 /* $Header: /tcpdump/master/tcpdump/ieee802_11_radio.h,v 1.1.2.1 2006/06/13 22:24:45 guy Exp $ */
      4 
      5 /*-
      6  * Copyright (c) 2003, 2004 David Young.  All rights reserved.
      7  *
      8  * Redistribution and use in source and binary forms, with or without
      9  * modification, are permitted provided that the following conditions
     10  * are met:
     11  * 1. Redistributions of source code must retain the above copyright
     12  *    notice, this list of conditions and the following disclaimer.
     13  * 2. Redistributions in binary form must reproduce the above copyright
     14  *    notice, this list of conditions and the following disclaimer in the
     15  *    documentation and/or other materials provided with the distribution.
     16  * 3. The name of David Young may not be used to endorse or promote
     17  *    products derived from this software without specific prior
     18  *    written permission.
     19  *
     20  * THIS SOFTWARE IS PROVIDED BY DAVID YOUNG ``AS IS'' AND ANY
     21  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
     22  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
     23  * PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL DAVID
     24  * YOUNG BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
     25  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
     26  * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     27  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
     28  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
     29  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
     31  * OF SUCH DAMAGE.
     32  */
     33 #ifndef _NET_IF_IEEE80211RADIOTAP_H_
     34 #define _NET_IF_IEEE80211RADIOTAP_H_
     35 
     36 /* A generic radio capture format is desirable. There is one for
     37  * Linux, but it is neither rigidly defined (there were not even
     38  * units given for some fields) nor easily extensible.
     39  *
     40  * I suggest the following extensible radio capture format. It is
     41  * based on a bitmap indicating which fields are present.
     42  *
     43  * I am trying to describe precisely what the application programmer
     44  * should expect in the following, and for that reason I tell the
     45  * units and origin of each measurement (where it applies), or else I
     46  * use sufficiently weaselly language ("is a monotonically nondecreasing
     47  * function of...") that I cannot set false expectations for lawyerly
     48  * readers.
     49  */
     50 #if defined(__KERNEL__) || defined(_KERNEL)
     51 #ifndef DLT_IEEE802_11_RADIO
     52 #define	DLT_IEEE802_11_RADIO	127	/* 802.11 plus WLAN header */
     53 #endif
     54 #endif /* defined(__KERNEL__) || defined(_KERNEL) */
     55 
     56 /* The radio capture header precedes the 802.11 header. */
     57 struct ieee80211_radiotap_header {
     58 	u_int8_t	it_version;	/* Version 0. Only increases
     59 					 * for drastic changes,
     60 					 * introduction of compatible
     61 					 * new fields does not count.
     62 					 */
     63 	u_int8_t	it_pad;
     64 	u_int16_t       it_len;         /* length of the whole
     65 					 * header in bytes, including
     66 					 * it_version, it_pad,
     67 					 * it_len, and data fields.
     68 					 */
     69 	u_int32_t       it_present;     /* A bitmap telling which
     70 					 * fields are present. Set bit 31
     71 					 * (0x80000000) to extend the
     72 					 * bitmap by another 32 bits.
     73 					 * Additional extensions are made
     74 					 * by setting bit 31.
     75 					 */
     76 } __attribute__((__packed__));
     77 
     78 /* Name                                 Data type       Units
     79  * ----                                 ---------       -----
     80  *
     81  * IEEE80211_RADIOTAP_TSFT              u_int64_t       microseconds
     82  *
     83  *      Value in microseconds of the MAC's 64-bit 802.11 Time
     84  *      Synchronization Function timer when the first bit of the
     85  *      MPDU arrived at the MAC. For received frames, only.
     86  *
     87  * IEEE80211_RADIOTAP_CHANNEL           2 x u_int16_t   MHz, bitmap
     88  *
     89  *      Tx/Rx frequency in MHz, followed by flags (see below).
     90  *
     91  * IEEE80211_RADIOTAP_FHSS              u_int16_t       see below
     92  *
     93  *      For frequency-hopping radios, the hop set (first byte)
     94  *      and pattern (second byte).
     95  *
     96  * IEEE80211_RADIOTAP_RATE              u_int8_t        500kb/s
     97  *
     98  *      Tx/Rx data rate
     99  *
    100  * IEEE80211_RADIOTAP_DBM_ANTSIGNAL     int8_t          decibels from
    101  *                                                      one milliwatt (dBm)
    102  *
    103  *      RF signal power at the antenna, decibel difference from
    104  *      one milliwatt.
    105  *
    106  * IEEE80211_RADIOTAP_DBM_ANTNOISE      int8_t          decibels from
    107  *                                                      one milliwatt (dBm)
    108  *
    109  *      RF noise power at the antenna, decibel difference from one
    110  *      milliwatt.
    111  *
    112  * IEEE80211_RADIOTAP_DB_ANTSIGNAL      u_int8_t        decibel (dB)
    113  *
    114  *      RF signal power at the antenna, decibel difference from an
    115  *      arbitrary, fixed reference.
    116  *
    117  * IEEE80211_RADIOTAP_DB_ANTNOISE       u_int8_t        decibel (dB)
    118  *
    119  *      RF noise power at the antenna, decibel difference from an
    120  *      arbitrary, fixed reference point.
    121  *
    122  * IEEE80211_RADIOTAP_LOCK_QUALITY      u_int16_t       unitless
    123  *
    124  *      Quality of Barker code lock. Unitless. Monotonically
    125  *      nondecreasing with "better" lock strength. Called "Signal
    126  *      Quality" in datasheets.  (Is there a standard way to measure
    127  *      this?)
    128  *
    129  * IEEE80211_RADIOTAP_TX_ATTENUATION    u_int16_t       unitless
    130  *
    131  *      Transmit power expressed as unitless distance from max
    132  *      power set at factory calibration.  0 is max power.
    133  *      Monotonically nondecreasing with lower power levels.
    134  *
    135  * IEEE80211_RADIOTAP_DB_TX_ATTENUATION u_int16_t       decibels (dB)
    136  *
    137  *      Transmit power expressed as decibel distance from max power
    138  *      set at factory calibration.  0 is max power.  Monotonically
    139  *      nondecreasing with lower power levels.
    140  *
    141  * IEEE80211_RADIOTAP_DBM_TX_POWER      int8_t          decibels from
    142  *                                                      one milliwatt (dBm)
    143  *
    144  *      Transmit power expressed as dBm (decibels from a 1 milliwatt
    145  *      reference). This is the absolute power level measured at
    146  *      the antenna port.
    147  *
    148  * IEEE80211_RADIOTAP_FLAGS             u_int8_t        bitmap
    149  *
    150  *      Properties of transmitted and received frames. See flags
    151  *      defined below.
    152  *
    153  * IEEE80211_RADIOTAP_ANTENNA           u_int8_t        antenna index
    154  *
    155  *      Unitless indication of the Rx/Tx antenna for this packet.
    156  *      The first antenna is antenna 0.
    157  *
    158  * IEEE80211_RADIOTAP_FCS           	u_int32_t       data
    159  *
    160  *	FCS from frame in network byte order.
    161  */
    162 enum ieee80211_radiotap_type {
    163 	IEEE80211_RADIOTAP_TSFT = 0,
    164 	IEEE80211_RADIOTAP_FLAGS = 1,
    165 	IEEE80211_RADIOTAP_RATE = 2,
    166 	IEEE80211_RADIOTAP_CHANNEL = 3,
    167 	IEEE80211_RADIOTAP_FHSS = 4,
    168 	IEEE80211_RADIOTAP_DBM_ANTSIGNAL = 5,
    169 	IEEE80211_RADIOTAP_DBM_ANTNOISE = 6,
    170 	IEEE80211_RADIOTAP_LOCK_QUALITY = 7,
    171 	IEEE80211_RADIOTAP_TX_ATTENUATION = 8,
    172 	IEEE80211_RADIOTAP_DB_TX_ATTENUATION = 9,
    173 	IEEE80211_RADIOTAP_DBM_TX_POWER = 10,
    174 	IEEE80211_RADIOTAP_ANTENNA = 11,
    175 	IEEE80211_RADIOTAP_DB_ANTSIGNAL = 12,
    176 	IEEE80211_RADIOTAP_DB_ANTNOISE = 13,
    177 	IEEE80211_RADIOTAP_EXT = 31
    178 };
    179 
    180 #ifndef _KERNEL
    181 /* Channel flags. */
    182 #define	IEEE80211_CHAN_TURBO	0x0010	/* Turbo channel */
    183 #define	IEEE80211_CHAN_CCK	0x0020	/* CCK channel */
    184 #define	IEEE80211_CHAN_OFDM	0x0040	/* OFDM channel */
    185 #define	IEEE80211_CHAN_2GHZ	0x0080	/* 2 GHz spectrum channel. */
    186 #define	IEEE80211_CHAN_5GHZ	0x0100	/* 5 GHz spectrum channel */
    187 #define	IEEE80211_CHAN_PASSIVE	0x0200	/* Only passive scan allowed */
    188 #define	IEEE80211_CHAN_DYN	0x0400	/* Dynamic CCK-OFDM channel */
    189 #define	IEEE80211_CHAN_GFSK	0x0800	/* GFSK channel (FHSS PHY) */
    190 #endif /* !_KERNEL */
    191 
    192 /* For IEEE80211_RADIOTAP_FLAGS */
    193 #define	IEEE80211_RADIOTAP_F_CFP	0x01	/* sent/received
    194 						 * during CFP
    195 						 */
    196 #define	IEEE80211_RADIOTAP_F_SHORTPRE	0x02	/* sent/received
    197 						 * with short
    198 						 * preamble
    199 						 */
    200 #define	IEEE80211_RADIOTAP_F_WEP	0x04	/* sent/received
    201 						 * with WEP encryption
    202 						 */
    203 #define	IEEE80211_RADIOTAP_F_FRAG	0x08	/* sent/received
    204 						 * with fragmentation
    205 						 */
    206 #define	IEEE80211_RADIOTAP_F_FCS	0x10	/* frame includes FCS */
    207 #define	IEEE80211_RADIOTAP_F_DATAPAD	0x20	/* frame has padding between
    208 						 * 802.11 header and payload
    209 						 * (to 32-bit boundary)
    210 						 */
    211 #define	IEEE80211_RADIOTAP_F_BADFCS	0x40	/* does not pass FCS check */
    212 
    213 #endif /* _NET_IF_IEEE80211RADIOTAP_H_ */
    214