xref: /freebsd/sys/net80211/ieee80211_radiotap.h (revision 6b3455a7665208c366849f0b2b3bc916fb97516e)
1 /* $FreeBSD$ */
2 /* $NetBSD: ieee80211_radiotap.h,v 1.3 2003/11/16 09:02:42 dyoung 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  * 3. The name of David Young may not be used to endorse or promote
16  *    products derived from this software without specific prior
17  *    written permission.
18  *
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
30  * OF SUCH DAMAGE.
31  */
32 #ifndef _NET_IF_IEEE80211RADIOTAP_H_
33 #define _NET_IF_IEEE80211RADIOTAP_H_
34 
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.
38  *
39  * I suggest the following extensible radio capture format. It is
40  * based on a bitmap indicating which fields are present.
41  *
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
47  * readers.
48  */
49 #ifdef _KERNEL
50 #ifndef DLT_IEEE802_11_RADIO
51 #define	DLT_IEEE802_11_RADIO	127	/* 802.11 plus WLAN header */
52 #endif
53 #endif /* _KERNEL */
54 
55 /* The radio capture header precedes the 802.11 header. */
56 struct ieee80211_radiotap_header {
57 	u_int8_t	it_version;	/* Version 0. Only increases
58 					 * for drastic changes,
59 					 * introduction of compatible
60 					 * new fields does not count.
61 					 */
62 	u_int8_t	it_pad;
63 	u_int16_t       it_len;         /* length of the whole
64 					 * header in bytes, including
65 					 * it_version, it_pad,
66 					 * it_len, and data fields.
67 					 */
68 	u_int32_t       it_present;     /* A bitmap telling which
69 					 * fields are present. Set bit 31
70 					 * (0x80000000) to extend the
71 					 * bitmap by another 32 bits.
72 					 * Additional extensions are made
73 					 * by setting bit 31.
74 					 */
75 } __attribute__((__packed__));
76 
77 /* Name                                 Data type       Units
78  * ----                                 ---------       -----
79  *
80  * IEEE80211_RADIOTAP_TSFT              u_int64_t       microseconds
81  *
82  *      Value in microseconds of the MAC's 64-bit 802.11 Time
83  *      Synchronization Function timer when the first bit of the
84  *      MPDU arrived at the MAC. For received frames, only.
85  *
86  * IEEE80211_RADIOTAP_CHANNEL           2 x u_int16_t   MHz, bitmap
87  *
88  *      Tx/Rx frequency in MHz, followed by flags (see below).
89  *
90  * IEEE80211_RADIOTAP_FHSS              u_int16_t       see below
91  *
92  *      For frequency-hopping radios, the hop set (first byte)
93  *      and pattern (second byte).
94  *
95  * IEEE80211_RADIOTAP_RATE              u_int8_t        500kb/s
96  *
97  *      Tx/Rx data rate
98  *
99  * IEEE80211_RADIOTAP_DBM_ANTSIGNAL     int8_t          decibels from
100  *                                                      one milliwatt (dBm)
101  *
102  *      RF signal power at the antenna, decibel difference from
103  *      one milliwatt.
104  *
105  * IEEE80211_RADIOTAP_DBM_ANTNOISE      int8_t          decibels from
106  *                                                      one milliwatt (dBm)
107  *
108  *      RF noise power at the antenna, decibel difference from one
109  *      milliwatt.
110  *
111  * IEEE80211_RADIOTAP_DB_ANTSIGNAL      u_int8_t        decibel (dB)
112  *
113  *      RF signal power at the antenna, decibel difference from an
114  *      arbitrary, fixed reference.
115  *
116  * IEEE80211_RADIOTAP_DB_ANTNOISE       u_int8_t        decibel (dB)
117  *
118  *      RF noise power at the antenna, decibel difference from an
119  *      arbitrary, fixed reference point.
120  *
121  * IEEE80211_RADIOTAP_BARKER_CODE_LOCK  u_int16_t       unitless
122  *
123  *      Quality of Barker code lock. Unitless. Monotonically
124  *      nondecreasing with "better" lock strength. Called "Signal
125  *      Quality" in datasheets.  (Is there a standard way to measure
126  *      this?)
127  *
128  * IEEE80211_RADIOTAP_TX_ATTENUATION    u_int16_t       unitless
129  *
130  *      Transmit power expressed as unitless distance from max
131  *      power set at factory calibration.  0 is max power.
132  *      Monotonically nondecreasing with lower power levels.
133  *
134  * IEEE80211_RADIOTAP_DB_TX_ATTENUATION u_int16_t       decibels (dB)
135  *
136  *      Transmit power expressed as decibel distance from max power
137  *      set at factory calibration.  0 is max power.  Monotonically
138  *      nondecreasing with lower power levels.
139  *
140  * IEEE80211_RADIOTAP_DBM_TX_POWER      int8_t          decibels from
141  *                                                      one milliwatt (dBm)
142  *
143  *      Transmit power expressed as dBm (decibels from a 1 milliwatt
144  *      reference). This is the absolute power level measured at
145  *      the antenna port.
146  *
147  * IEEE80211_RADIOTAP_FLAGS             u_int8_t        bitmap
148  *
149  *      Properties of transmitted and received frames. See flags
150  *      defined below.
151  *
152  * IEEE80211_RADIOTAP_ANTENNA           u_int8_t        antenna index
153  *
154  *      Unitless indication of the Rx/Tx antenna for this packet.
155  *      The first antenna is antenna 0.
156  *
157  * IEEE80211_RADIOTAP_FCS           	u_int32_t       data
158  *
159  *	FCS from frame in network byte order.
160  */
161 enum ieee80211_radiotap_type {
162 	IEEE80211_RADIOTAP_TSFT = 0,
163 	IEEE80211_RADIOTAP_FLAGS = 1,
164 	IEEE80211_RADIOTAP_RATE = 2,
165 	IEEE80211_RADIOTAP_CHANNEL = 3,
166 	IEEE80211_RADIOTAP_FHSS = 4,
167 	IEEE80211_RADIOTAP_DBM_ANTSIGNAL = 5,
168 	IEEE80211_RADIOTAP_DBM_ANTNOISE = 6,
169 	IEEE80211_RADIOTAP_LOCK_QUALITY = 7,
170 	IEEE80211_RADIOTAP_TX_ATTENUATION = 8,
171 	IEEE80211_RADIOTAP_DB_TX_ATTENUATION = 9,
172 	IEEE80211_RADIOTAP_DBM_TX_POWER = 10,
173 	IEEE80211_RADIOTAP_ANTENNA = 11,
174 	IEEE80211_RADIOTAP_DB_ANTSIGNAL = 12,
175 	IEEE80211_RADIOTAP_DB_ANTNOISE = 13,
176 	IEEE80211_RADIOTAP_FCS = 14,
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 
207 #endif /* _NET_IF_IEEE80211RADIOTAP_H_ */
208