2 /* $NetBSD: ieee80211_radiotap.h,v 1.10 2005/01/04 00:34:58 dyoung Exp $ */
5 * Copyright (c) 2003, 2004 David Young. All rights reserved.
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
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
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
32 #ifndef _NET_IF_IEEE80211RADIOTAP_H_
33 #define _NET_IF_IEEE80211RADIOTAP_H_
35 /* A generic radio capture format is desirable. There is one for
36 * Linux, but it is neither rigidly defined (there were not even
37 * units given for some fields) nor easily extensible.
39 * I suggest the following extensible radio capture format. It is
40 * based on a bitmap indicating which fields are present.
42 * I am trying to describe precisely what the application programmer
43 * should expect in the following, and for that reason I tell the
44 * units and origin of each measurement (where it applies), or else I
45 * use sufficiently weaselly language ("is a monotonically nondecreasing
46 * function of...") that I cannot set false expectations for lawyerly
49 #if defined(__KERNEL__) || defined(_KERNEL)
50 #ifndef DLT_IEEE802_11_RADIO
51 #define DLT_IEEE802_11_RADIO 127 /* 802.11 plus WLAN header */
53 #endif /* defined(__KERNEL__) || defined(_KERNEL) */
55 /* XXX tcpdump/libpcap do not tolerate variable-length headers,
56 * yet, so we pad every radiotap header to 64 bytes. Ugh.
58 #define IEEE80211_RADIOTAP_HDRLEN 64
60 /* The radio capture header precedes the 802.11 header. */
61 struct ieee80211_radiotap_header {
62 u_int8_t it_version; /* Version 0. Only increases
63 * for drastic changes,
64 * introduction of compatible
65 * new fields does not count.
68 u_int16_t it_len; /* length of the whole
69 * header in bytes, including
71 * it_len, and data fields.
73 u_int32_t it_present; /* A bitmap telling which
74 * fields are present. Set bit 31
75 * (0x80000000) to extend the
76 * bitmap by another 32 bits.
77 * Additional extensions are made
80 } __attribute__((__packed__));
82 /* Name Data type Units
83 * ---- --------- -----
85 * IEEE80211_RADIOTAP_TSFT u_int64_t microseconds
87 * Value in microseconds of the MAC's 64-bit 802.11 Time
88 * Synchronization Function timer when the first bit of the
89 * MPDU arrived at the MAC. For received frames, only.
91 * IEEE80211_RADIOTAP_CHANNEL 2 x u_int16_t MHz, bitmap
93 * Tx/Rx frequency in MHz, followed by flags (see below).
95 * IEEE80211_RADIOTAP_FHSS u_int16_t see below
97 * For frequency-hopping radios, the hop set (first byte)
98 * and pattern (second byte).
100 * IEEE80211_RADIOTAP_RATE u_int8_t 500kb/s
104 * IEEE80211_RADIOTAP_DBM_ANTSIGNAL int8_t decibels from
105 * one milliwatt (dBm)
107 * RF signal power at the antenna, decibel difference from
110 * IEEE80211_RADIOTAP_DBM_ANTNOISE int8_t decibels from
111 * one milliwatt (dBm)
113 * RF noise power at the antenna, decibel difference from one
116 * IEEE80211_RADIOTAP_DB_ANTSIGNAL u_int8_t decibel (dB)
118 * RF signal power at the antenna, decibel difference from an
119 * arbitrary, fixed reference.
121 * IEEE80211_RADIOTAP_DB_ANTNOISE u_int8_t decibel (dB)
123 * RF noise power at the antenna, decibel difference from an
124 * arbitrary, fixed reference point.
126 * IEEE80211_RADIOTAP_LOCK_QUALITY u_int16_t unitless
128 * Quality of Barker code lock. Unitless. Monotonically
129 * nondecreasing with "better" lock strength. Called "Signal
130 * Quality" in datasheets. (Is there a standard way to measure
133 * IEEE80211_RADIOTAP_TX_ATTENUATION u_int16_t unitless
135 * Transmit power expressed as unitless distance from max
136 * power set at factory calibration. 0 is max power.
137 * Monotonically nondecreasing with lower power levels.
139 * IEEE80211_RADIOTAP_DB_TX_ATTENUATION u_int16_t decibels (dB)
141 * Transmit power expressed as decibel distance from max power
142 * set at factory calibration. 0 is max power. Monotonically
143 * nondecreasing with lower power levels.
145 * IEEE80211_RADIOTAP_DBM_TX_POWER int8_t decibels from
146 * one milliwatt (dBm)
148 * Transmit power expressed as dBm (decibels from a 1 milliwatt
149 * reference). This is the absolute power level measured at
152 * IEEE80211_RADIOTAP_FLAGS u_int8_t bitmap
154 * Properties of transmitted and received frames. See flags
157 * IEEE80211_RADIOTAP_ANTENNA u_int8_t antenna index
159 * Unitless indication of the Rx/Tx antenna for this packet.
160 * The first antenna is antenna 0.
162 * IEEE80211_RADIOTAP_FCS u_int32_t data
164 * FCS from frame in network byte order.
166 enum ieee80211_radiotap_type {
167 IEEE80211_RADIOTAP_TSFT = 0,
168 IEEE80211_RADIOTAP_FLAGS = 1,
169 IEEE80211_RADIOTAP_RATE = 2,
170 IEEE80211_RADIOTAP_CHANNEL = 3,
171 IEEE80211_RADIOTAP_FHSS = 4,
172 IEEE80211_RADIOTAP_DBM_ANTSIGNAL = 5,
173 IEEE80211_RADIOTAP_DBM_ANTNOISE = 6,
174 IEEE80211_RADIOTAP_LOCK_QUALITY = 7,
175 IEEE80211_RADIOTAP_TX_ATTENUATION = 8,
176 IEEE80211_RADIOTAP_DB_TX_ATTENUATION = 9,
177 IEEE80211_RADIOTAP_DBM_TX_POWER = 10,
178 IEEE80211_RADIOTAP_ANTENNA = 11,
179 IEEE80211_RADIOTAP_DB_ANTSIGNAL = 12,
180 IEEE80211_RADIOTAP_DB_ANTNOISE = 13,
181 IEEE80211_RADIOTAP_EXT = 31,
186 #define IEEE80211_CHAN_TURBO 0x0010 /* Turbo channel */
187 #define IEEE80211_CHAN_CCK 0x0020 /* CCK channel */
188 #define IEEE80211_CHAN_OFDM 0x0040 /* OFDM channel */
189 #define IEEE80211_CHAN_2GHZ 0x0080 /* 2 GHz spectrum channel. */
190 #define IEEE80211_CHAN_5GHZ 0x0100 /* 5 GHz spectrum channel */
191 #define IEEE80211_CHAN_PASSIVE 0x0200 /* Only passive scan allowed */
192 #define IEEE80211_CHAN_DYN 0x0400 /* Dynamic CCK-OFDM channel */
193 #define IEEE80211_CHAN_GFSK 0x0800 /* GFSK channel (FHSS PHY) */
194 #endif /* !_KERNEL */
196 /* For IEEE80211_RADIOTAP_FLAGS */
197 #define IEEE80211_RADIOTAP_F_CFP 0x01 /* sent/received
200 #define IEEE80211_RADIOTAP_F_SHORTPRE 0x02 /* sent/received
204 #define IEEE80211_RADIOTAP_F_WEP 0x04 /* sent/received
205 * with WEP encryption
207 #define IEEE80211_RADIOTAP_F_FRAG 0x08 /* sent/received
210 #define IEEE80211_RADIOTAP_F_FCS 0x10 /* frame includes FCS */
211 #define IEEE80211_RADIOTAP_F_DATAPAD 0x20 /* frame has padding between
212 * 802.11 header and payload
213 * (to 32-bit boundary)
215 #define IEEE80211_RADIOTAP_F_BADFCS 0x40 /* does not pass FCS check */
217 #endif /* _NET_IF_IEEE80211RADIOTAP_H_ */