1/* $FreeBSD: src/sys/net80211/ieee80211_radiotap.h,v 1.11 2007/12/13 01:23:40 sam Exp $ */
2/* $NetBSD: ieee80211_radiotap.h,v 1.24 2011/02/25 10:45:57 tron 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 *
16 * THIS SOFTWARE IS PROVIDED BY DAVID YOUNG ``AS IS'' AND ANY
17 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
18 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
19 * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL DAVID
20 * YOUNG BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
21 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
22 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
24 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
25 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
27 * OF SUCH DAMAGE.
28 */
29#ifndef _NET80211_IEEE80211_RADIOTAP_H_
30#define _NET80211_IEEE80211_RADIOTAP_H_
31
32/* A generic radio capture format is desirable. It must be
33 * rigidly defined (e.g., units for fields should be given),
34 * and easily extensible.
35 *
36 * The following is an extensible radio capture format. It is
37 * based on a bitmap indicating which fields are present.
38 *
39 * I am trying to describe precisely what the application programmer
40 * should expect in the following, and for that reason I tell the
41 * units and origin of each measurement (where it applies), or else I
42 * use sufficiently weaselly language ("is a monotonically nondecreasing
43 * function of...") that I cannot set false expectations for lawyerly
44 * readers.
45 */
46#if defined(__KERNEL__) || defined(_KERNEL)
47#ifndef DLT_IEEE802_11_RADIO
48#define DLT_IEEE802_11_RADIO 127 /* 802.11 plus WLAN header */
49#endif
50#endif /* defined(__KERNEL__) || defined(_KERNEL) */
51
52/* XXX tcpdump/libpcap do not tolerate variable-length headers,
53 * yet, so we pad every radiotap header to 64 bytes. Ugh.
54 */
55#define IEEE80211_RADIOTAP_HDRLEN 64
56
57/*
58 * The radio capture header precedes the 802.11 header.
59 *
60 * Note well: all radiotap fields are little-endian.
61 */
62struct ieee80211_radiotap_header {
63 uint8_t it_version; /* Version 0. Only increases
64 * for drastic changes,
65 * introduction of compatible
66 * new fields does not count.
67 */
68 uint8_t it_pad;
69 uint16_t it_len; /* length of the whole
70 * header in bytes, including
71 * it_version, it_pad,
72 * it_len, and data fields.
73 */
74 uint32_t it_present; /* A bitmap telling which
75 * fields are present. Set bit 31
76 * (0x80000000) to extend the
77 * bitmap by another 32 bits.
78 * Additional extensions are made
79 * by setting bit 31.
80 */
81} __packed __aligned(8);
82
83/*
84 * Name Data type Units
85 * ---- --------- -----
86 *
87 * IEEE80211_RADIOTAP_TSFT uint64_t microseconds
88 *
89 * Value in microseconds of the MAC's 64-bit 802.11 Time
90 * Synchronization Function timer when the first bit of the
91 * MPDU arrived at the MAC. For received frames, only.
92 *
93 * IEEE80211_RADIOTAP_CHANNEL 2 x uint16_t MHz, bitmap
94 *
95 * Tx/Rx frequency in MHz, followed by flags (see below).
96 *
97 * IEEE80211_RADIOTAP_FHSS uint16_t see below
98 *
99 * For frequency-hopping radios, the hop set (first byte)
100 * and pattern (second byte).
101 *
102 * IEEE80211_RADIOTAP_RATE uint8_t 500kb/s
103 *
104 * Tx/Rx data rate
105 *
106 * IEEE80211_RADIOTAP_DBM_ANTSIGNAL int8_t decibels from
107 * one milliwatt (dBm)
108 *
109 * RF signal power at the antenna, decibel difference from
110 * one milliwatt.
111 *
112 * IEEE80211_RADIOTAP_DBM_ANTNOISE int8_t decibels from
113 * one milliwatt (dBm)
114 *
115 * RF noise power at the antenna, decibel difference from one
116 * milliwatt.
117 *
118 * IEEE80211_RADIOTAP_DB_ANTSIGNAL uint8_t decibel (dB)
119 *
120 * RF signal power at the antenna, decibel difference from an
121 * arbitrary, fixed reference.
122 *
123 * IEEE80211_RADIOTAP_DB_ANTNOISE uint8_t decibel (dB)
124 *
125 * RF noise power at the antenna, decibel difference from an
126 * arbitrary, fixed reference point.
127 *
128 * IEEE80211_RADIOTAP_LOCK_QUALITY uint16_t unitless
129 *
130 * Quality of Barker code lock. Unitless. Monotonically
131 * nondecreasing with "better" lock strength. Called "Signal
132 * Quality" in datasheets. (Is there a standard way to measure
133 * this?)
134 *
135 * IEEE80211_RADIOTAP_TX_ATTENUATION uint16_t unitless
136 *
137 * Transmit power expressed as unitless distance from max
138 * power set at factory calibration. 0 is max power.
139 * Monotonically nondecreasing with lower power levels.
140 *
141 * IEEE80211_RADIOTAP_DB_TX_ATTENUATION uint16_t decibels (dB)
142 *
143 * Transmit power expressed as decibel distance from max power
144 * set at factory calibration. 0 is max power. Monotonically
145 * nondecreasing with lower power levels.
146 *
147 * IEEE80211_RADIOTAP_DBM_TX_POWER int8_t decibels from
148 * one milliwatt (dBm)
149 *
150 * Transmit power expressed as dBm (decibels from a 1 milliwatt
151 * reference). This is the absolute power level measured at
152 * the antenna port.
153 *
154 * IEEE80211_RADIOTAP_FLAGS uint8_t bitmap
155 *
156 * Properties of transmitted and received frames. See flags
157 * defined below.
158 *
159 * IEEE80211_RADIOTAP_ANTENNA uint8_t antenna index
160 *
161 * Unitless indication of the Rx/Tx antenna for this packet.
162 * The first antenna is antenna 0.
163 *
164 * IEEE80211_RADIOTAP_RX_FLAGS uint16_t bitmap
165 *
166 * Properties of received frames. See flags defined below.
167 *
168 * IEEE80211_RADIOTAP_TX_FLAGS uint16_t bitmap
169 *
170 * Properties of transmitted frames. See flags defined below.
171 *
172 * IEEE80211_RADIOTAP_RTS_RETRIES uint8_t data
173 *
174 * Number of rts retries a transmitted frame used.
175 *
176 * IEEE80211_RADIOTAP_DATA_RETRIES uint8_t data
177 *
178 * Number of unicast retries a transmitted frame used.
179 *
180 * IEEE80211_RADIOTAP_XCHANNEL uint32_t bitmap
181 * uint16_t MHz
182 * uint8_t channel number
183 * int8_t .5 dBm
184 *
185 * Extended channel specification: flags (see below) followed by
186 * frequency in MHz, the corresponding IEEE channel number, and
187 * finally the maximum regulatory transmit power cap in .5 dBm
188 * units. This property supersedes IEEE80211_RADIOTAP_CHANNEL
189 * and only one of the two should be present.
190 */
191enum ieee80211_radiotap_type {
192 IEEE80211_RADIOTAP_TSFT = 0,
193 IEEE80211_RADIOTAP_FLAGS = 1,
194 IEEE80211_RADIOTAP_RATE = 2,
195 IEEE80211_RADIOTAP_CHANNEL = 3,
196 IEEE80211_RADIOTAP_FHSS = 4,
197 IEEE80211_RADIOTAP_DBM_ANTSIGNAL = 5,
198 IEEE80211_RADIOTAP_DBM_ANTNOISE = 6,
199 IEEE80211_RADIOTAP_LOCK_QUALITY = 7,
200 IEEE80211_RADIOTAP_TX_ATTENUATION = 8,
201 IEEE80211_RADIOTAP_DB_TX_ATTENUATION = 9,
202 IEEE80211_RADIOTAP_DBM_TX_POWER = 10,
203 IEEE80211_RADIOTAP_ANTENNA = 11,
204 IEEE80211_RADIOTAP_DB_ANTSIGNAL = 12,
205 IEEE80211_RADIOTAP_DB_ANTNOISE = 13,
206 IEEE80211_RADIOTAP_RX_FLAGS = 14,
207 IEEE80211_RADIOTAP_TX_FLAGS = 15,
208 IEEE80211_RADIOTAP_RTS_RETRIES = 16,
209 IEEE80211_RADIOTAP_DATA_RETRIES = 17,
210 IEEE80211_RADIOTAP_XCHANNEL = 18,
211 IEEE80211_RADIOTAP_EXT = 31
212};
213
214/* For IEEE80211_RADIOTAP_FLAGS */
215#define IEEE80211_RADIOTAP_F_CFP 0x01 /* sent/received
216 * during CFP
217 */
218#define IEEE80211_RADIOTAP_F_SHORTPRE 0x02 /* sent/received
219 * with short
220 * preamble
221 */
222#define IEEE80211_RADIOTAP_F_WEP 0x04 /* sent/received
223 * with WEP encryption
224 */
225#define IEEE80211_RADIOTAP_F_FRAG 0x08 /* sent/received
226 * with fragmentation
227 */
228#define IEEE80211_RADIOTAP_F_FCS 0x10 /* frame includes FCS */
229#define IEEE80211_RADIOTAP_F_DATAPAD 0x20 /* frame has padding between
230 * 802.11 header and payload
231 * (to 32-bit boundary)
232 */
233#define IEEE80211_RADIOTAP_F_BADFCS 0x40 /* does not pass FCS check */
234#define IEEE80211_RADIOTAP_F_SHORTGI 0x80 /* HT short GI */
235
236/* For IEEE80211_RADIOTAP_RX_FLAGS */
237#define IEEE80211_RADIOTAP_F_RX_BADFCS 0x0001 /* Frame failed CRC check.
238 *
239 * Deprecated: use the flag
240 * IEEE80211_RADIOTAP_F_BADFCS in
241 * the IEEE80211_RADIOTAP_FLAGS
242 * field, instead.
243 */
244
245/* For IEEE80211_RADIOTAP_TX_FLAGS */
246#define IEEE80211_RADIOTAP_F_TX_FAIL 0x0001 /* failed due to excessive
247 * retries
248 */
249#define IEEE80211_RADIOTAP_F_TX_CTS 0x0002 /* used cts 'protection' */
250#define IEEE80211_RADIOTAP_F_TX_RTS 0x0004 /* used rts/cts handshake */
251
252#endif /* !_NET80211_IEEE80211_RADIOTAP_H_ */
253