1 /* $OpenBSD: ieee80211_radiotap.h,v 1.8 2006/06/23 21:34:15 reyk 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 * 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
51 /* XXX tcpdump/libpcap do not tolerate variable-length headers,
52 * yet, so we pad every radiotap header to 64 bytes. Ugh.
53 */
54 #define IEEE80211_RADIOTAP_HDRLEN 64
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 } __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_BARKER_CODE_LOCK 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 * IEEE80211_RADIOTAP_HWQUEUE u_int8_t data
163 *
164 * A specific hardware queue (used by WME)
165 *
166 * IEEE80211_RADIOTAP_RSSI 2x u_int8_t RSSI, max RSSI
167 *
168 * A relative Received Signal Strength Index
169 */
170 enum ieee80211_radiotap_type {
171 IEEE80211_RADIOTAP_TSFT = 0,
172 IEEE80211_RADIOTAP_FLAGS = 1,
173 IEEE80211_RADIOTAP_RATE = 2,
174 IEEE80211_RADIOTAP_CHANNEL = 3,
175 IEEE80211_RADIOTAP_FHSS = 4,
176 IEEE80211_RADIOTAP_DBM_ANTSIGNAL = 5,
177 IEEE80211_RADIOTAP_DBM_ANTNOISE = 6,
178 IEEE80211_RADIOTAP_LOCK_QUALITY = 7,
179 IEEE80211_RADIOTAP_TX_ATTENUATION = 8,
180 IEEE80211_RADIOTAP_DB_TX_ATTENUATION = 9,
181 IEEE80211_RADIOTAP_DBM_TX_POWER = 10,
182 IEEE80211_RADIOTAP_ANTENNA = 11,
183 IEEE80211_RADIOTAP_DB_ANTSIGNAL = 12,
184 IEEE80211_RADIOTAP_DB_ANTNOISE = 13,
185 IEEE80211_RADIOTAP_FCS = 14,
186 IEEE80211_RADIOTAP_HWQUEUE = 15,
187 IEEE80211_RADIOTAP_RSSI = 16,
188 IEEE80211_RADIOTAP_EXT = 31
189 };
190
191 /* For IEEE80211_RADIOTAP_FLAGS */
192 #define IEEE80211_RADIOTAP_F_CFP 0x01 /* sent/received
193 * during CFP
194 */
195 #define IEEE80211_RADIOTAP_F_SHORTPRE 0x02 /* sent/received
196 * with short
197 * preamble
198 */
199 #define IEEE80211_RADIOTAP_F_WEP 0x04 /* sent/received
200 * with WEP encryption
201 */
202 #define IEEE80211_RADIOTAP_F_FRAG 0x08 /* sent/received
203 * with fragmentation
204 */
205
206 #endif /* _NET_IF_IEEE80211RADIOTAP_H_ */