1/* $OpenBSD: ieee80211_radiotap.h,v 1.17 2022/03/14 15:06:04 stsp Exp $ */
2/* $FreeBSD: src/sys/net80211/ieee80211_radiotap.h,v 1.3 2004/04/05 22:13:21 sam Exp $ */
3/* $NetBSD: ieee80211_radiotap.h,v 1.9 2004/06/06 04:13:28 dyoung 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 *
17 * THIS SOFTWARE IS PROVIDED BY DAVID YOUNG ``AS IS'' AND ANY
18 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
19 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
20 * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL DAVID
21 * YOUNG BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
22 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
23 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
25 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
26 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
28 * OF SUCH DAMAGE.
29 */
30#ifndef _NET_IF_IEEE80211RADIOTAP_H_
31#define _NET_IF_IEEE80211RADIOTAP_H_
32
33/* A generic radio capture format is desirable. There is one for
34 * Linux, but it is neither rigidly defined (there were not even
35 * units given for some fields) nor easily extensible.
36 *
37 * I suggest the following extensible radio capture format. It is
38 * based on a bitmap indicating which fields are present.
39 *
40 * I am trying to describe precisely what the application programmer
41 * should expect in the following, and for that reason I tell the
42 * units and origin of each measurement (where it applies), or else I
43 * use sufficiently weaselly language ("is a monotonically nondecreasing
44 * function of...") that I cannot set false expectations for lawyerly
45 * readers.
46 */
47
48/* XXX tcpdump/libpcap do not tolerate variable-length headers,
49 * yet, so we pad every radiotap header to 64 bytes. Ugh.
50 */
51#define IEEE80211_RADIOTAP_HDRLEN 64
52
53/* The radio capture header precedes the 802.11 header. */
54struct ieee80211_radiotap_header {
55 u_int8_t it_version; /* Version 0. Only increases
56 * for drastic changes,
57 * introduction of compatible
58 * new fields does not count.
59 */
60 u_int8_t it_pad;
61 u_int16_t it_len; /* length of the whole
62 * header in bytes, including
63 * it_version, it_pad,
64 * it_len, and data fields.
65 */
66 u_int32_t it_present; /* A bitmap telling which
67 * fields are present. Set bit 31
68 * (0x80000000) to extend the
69 * bitmap by another 32 bits.
70 * Additional extensions are made
71 * by setting bit 31.
72 */
73} __packed;
74
75/* Name Data type Units
76 * ---- --------- -----
77 *
78 * IEEE80211_RADIOTAP_TSFT u_int64_t microseconds
79 *
80 * Value in microseconds of the MAC's 64-bit 802.11 Time
81 * Synchronization Function timer when the first bit of the
82 * MPDU arrived at the MAC. For received frames, only.
83 *
84 * IEEE80211_RADIOTAP_CHANNEL 2 x u_int16_t MHz, bitmap
85 *
86 * Tx/Rx frequency in MHz, followed by flags (see below).
87 *
88 * IEEE80211_RADIOTAP_FHSS u_int16_t see below
89 *
90 * For frequency-hopping radios, the hop set (first byte)
91 * and pattern (second byte).
92 *
93 * IEEE80211_RADIOTAP_RATE u_int8_t 500kb/s or MCS index
94 *
95 * Tx/Rx data rate in units of 500kb/s. If the high bit (0x80) is set
96 * the remaining bits contain an MCS index instead of a date rate.
97 *
98 * IEEE80211_RADIOTAP_DBM_ANTSIGNAL int8_t decibels from
99 * one milliwatt (dBm)
100 *
101 * RF signal power at the antenna, decibel difference from
102 * one milliwatt.
103 *
104 * IEEE80211_RADIOTAP_DBM_ANTNOISE int8_t decibels from
105 * one milliwatt (dBm)
106 *
107 * RF noise power at the antenna, decibel difference from one
108 * milliwatt.
109 *
110 * IEEE80211_RADIOTAP_DB_ANTSIGNAL u_int8_t decibel (dB)
111 *
112 * RF signal power at the antenna, decibel difference from an
113 * arbitrary, fixed reference.
114 *
115 * IEEE80211_RADIOTAP_DB_ANTNOISE u_int8_t decibel (dB)
116 *
117 * RF noise power at the antenna, decibel difference from an
118 * arbitrary, fixed reference point.
119 *
120 * IEEE80211_RADIOTAP_BARKER_CODE_LOCK u_int16_t unitless
121 *
122 * Quality of Barker code lock. Unitless. Monotonically
123 * nondecreasing with "better" lock strength. Called "Signal
124 * Quality" in datasheets. (Is there a standard way to measure
125 * this?)
126 *
127 * IEEE80211_RADIOTAP_TX_ATTENUATION u_int16_t unitless
128 *
129 * Transmit power expressed as unitless distance from max
130 * power set at factory calibration. 0 is max power.
131 * Monotonically nondecreasing with lower power levels.
132 *
133 * IEEE80211_RADIOTAP_DB_TX_ATTENUATION u_int16_t decibels (dB)
134 *
135 * Transmit power expressed as decibel distance from max power
136 * set at factory calibration. 0 is max power. Monotonically
137 * nondecreasing with lower power levels.
138 *
139 * IEEE80211_RADIOTAP_DBM_TX_POWER int8_t decibels from
140 * one milliwatt (dBm)
141 *
142 * Transmit power expressed as dBm (decibels from a 1 milliwatt
143 * reference). This is the absolute power level measured at
144 * the antenna port.
145 *
146 * IEEE80211_RADIOTAP_FLAGS u_int8_t bitmap
147 *
148 * Properties of transmitted and received frames. See flags
149 * defined below.
150 *
151 * IEEE80211_RADIOTAP_ANTENNA u_int8_t antenna index
152 *
153 * Unitless indication of the Rx/Tx antenna for this packet.
154 * The first antenna is antenna 0.
155 *
156 * IEEE80211_RADIOTAP_FCS u_int32_t data
157 *
158 * FCS from frame in network byte order.
159 *
160 * IEEE80211_RADIOTAP_RSSI 2x u_int8_t RSSI, max RSSI
161 *
162 * A relative Received Signal Strength Index
163 */
164enum ieee80211_radiotap_type {
165 IEEE80211_RADIOTAP_TSFT = 0,
166 IEEE80211_RADIOTAP_FLAGS = 1,
167 IEEE80211_RADIOTAP_RATE = 2,
168 IEEE80211_RADIOTAP_CHANNEL = 3,
169 IEEE80211_RADIOTAP_FHSS = 4,
170 IEEE80211_RADIOTAP_DBM_ANTSIGNAL = 5,
171 IEEE80211_RADIOTAP_DBM_ANTNOISE = 6,
172 IEEE80211_RADIOTAP_LOCK_QUALITY = 7,
173 IEEE80211_RADIOTAP_TX_ATTENUATION = 8,
174 IEEE80211_RADIOTAP_DB_TX_ATTENUATION = 9,
175 IEEE80211_RADIOTAP_DBM_TX_POWER = 10,
176 IEEE80211_RADIOTAP_ANTENNA = 11,
177 IEEE80211_RADIOTAP_DB_ANTSIGNAL = 12,
178 IEEE80211_RADIOTAP_DB_ANTNOISE = 13,
179 IEEE80211_RADIOTAP_FCS = 14,
180 IEEE80211_RADIOTAP_RSSI = 16,
181 IEEE80211_RADIOTAP_EXT = 31
182};
183
184#ifndef _KERNEL
185/* For IEEE80211_RADIOTAP_CHANNEL */
186#define IEEE80211_CHAN_CCK 0x0020 /* CCK channel */
187#define IEEE80211_CHAN_OFDM 0x0040 /* OFDM channel */
188#define IEEE80211_CHAN_2GHZ 0x0080 /* 2 GHz spectrum channel */
189#define IEEE80211_CHAN_5GHZ 0x0100 /* 5 GHz spectrum channel */
190#define IEEE80211_CHAN_PASSIVE 0x0200 /* Only passive scan allowed */
191#define IEEE80211_CHAN_DYN 0x0400 /* Dynamic CCK-OFDM channel */
192#define IEEE80211_CHAN_GFSK 0x0800 /* GFSK channel (FHSS PHY) */
193#define IEEE80211_CHAN_XR 0x1000 /* Extended range OFDM channel */
194#define IEEE80211_CHAN_HT 0x2000 /* 11n/HT channel */
195#define IEEE80211_CHAN_VHT 0x4000 /* 11ac/VHT channel */
196#define IEEE80211_CHAN_40MHZ 0x8000 /* use of 40 MHz is allowed */
197#endif /* !_KERNEL */
198
199/* For IEEE80211_RADIOTAP_FLAGS */
200#define IEEE80211_RADIOTAP_F_CFP 0x01 /* sent/received
201 * during CFP
202 */
203#define IEEE80211_RADIOTAP_F_SHORTPRE 0x02 /* sent/received
204 * with short
205 * preamble
206 */
207#define IEEE80211_RADIOTAP_F_WEP 0x04 /* sent/received
208 * with WEP encryption
209 */
210#define IEEE80211_RADIOTAP_F_FRAG 0x08 /* sent/received
211 * with fragmentation
212 */
213#define IEEE80211_RADIOTAP_F_FCS 0x10 /* frame includes FCS */
214
215#endif /* _NET_IF_IEEE80211RADIOTAP_H_ */