1 /* $FreeBSD: src/sys/net80211/ieee80211_radiotap.h,v 1.5.2.1 2006/01/29 07:13:58 sam Exp $ */
2 /* $NetBSD: ieee80211_radiotap.h,v 1.10 2005/01/04 00:34:58 dyoung Exp $ */
3 /* $DragonFly: src/sys/netproto/802_11/ieee80211_radiotap.h,v 1.2 2006/05/18 13:51:46 sephe 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 /*
37  * A generic radio capture format is desirable. There is one for
38  * Linux, but it is neither rigidly defined (there were not even
39  * units given for some fields) nor easily extensible.
40  *
41  * I suggest the following extensible radio capture format. It is
42  * based on a bitmap indicating which fields are present.
43  *
44  * I am trying to describe precisely what the application programmer
45  * should expect in the following, and for that reason I tell the
46  * units and origin of each measurement (where it applies), or else I
47  * use sufficiently weaselly language ("is a monotonically nondecreasing
48  * function of...") that I cannot set false expectations for lawyerly
49  * readers.
50  */
51 #if defined(__KERNEL__) || defined(_KERNEL)
52 #ifndef DLT_IEEE802_11_RADIO
53 #define	DLT_IEEE802_11_RADIO	127	/* 802.11 plus WLAN header */
54 #endif
55 #endif /* defined(__KERNEL__) || defined(_KERNEL) */
56 
57 /*
58  * XXX tcpdump/libpcap do not tolerate variable-length headers,
59  * yet, so we pad every radiotap header to 64 bytes. Ugh.
60  */
61 #define IEEE80211_RADIOTAP_HDRLEN	64
62 
63 /* The radio capture header precedes the 802.11 header. */
64 struct ieee80211_radiotap_header {
65 	uint8_t		it_version;	/* Version 0. Only increases
66 					 * for drastic changes,
67 					 * introduction of compatible
68 					 * new fields does not count.
69 					 */
70 	uint8_t		it_pad;
71 	uint16_t	it_len;		/* length of the whole
72 					 * header in bytes, including
73 					 * it_version, it_pad,
74 					 * it_len, and data fields.
75 					 */
76 	uint32_t	it_present;	/* A bitmap telling which
77 					 * fields are present. Set bit 31
78 					 * (0x80000000) to extend the
79 					 * bitmap by another 32 bits.
80 					 * Additional extensions are made
81 					 * by setting bit 31.
82 					 */
83 } __packed;
84 
85 /* Name                                 Data type       Units
86  * ----                                 ---------       -----
87  *
88  * IEEE80211_RADIOTAP_TSFT              uint64_t        microseconds
89  *
90  *      Value in microseconds of the MAC's 64-bit 802.11 Time
91  *      Synchronization Function timer when the first bit of the
92  *      MPDU arrived at the MAC. For received frames, only.
93  *
94  * IEEE80211_RADIOTAP_CHANNEL           2 x uint16_t    MHz, bitmap
95  *
96  *      Tx/Rx frequency in MHz, followed by flags (see below).
97  *
98  * IEEE80211_RADIOTAP_FHSS              uint16_t        see below
99  *
100  *      For frequency-hopping radios, the hop set (first byte)
101  *      and pattern (second byte).
102  *
103  * IEEE80211_RADIOTAP_RATE              uint8_t         500kb/s
104  *
105  *      Tx/Rx data rate
106  *
107  * IEEE80211_RADIOTAP_DBM_ANTSIGNAL     int8_t          decibels from
108  *                                                      one milliwatt (dBm)
109  *
110  *      RF signal power at the antenna, decibel difference from
111  *      one milliwatt.
112  *
113  * IEEE80211_RADIOTAP_DBM_ANTNOISE      int8_t          decibels from
114  *                                                      one milliwatt (dBm)
115  *
116  *      RF noise power at the antenna, decibel difference from one
117  *      milliwatt.
118  *
119  * IEEE80211_RADIOTAP_DB_ANTSIGNAL      uint8_t         decibel (dB)
120  *
121  *      RF signal power at the antenna, decibel difference from an
122  *      arbitrary, fixed reference.
123  *
124  * IEEE80211_RADIOTAP_DB_ANTNOISE       uint8_t         decibel (dB)
125  *
126  *      RF noise power at the antenna, decibel difference from an
127  *      arbitrary, fixed reference point.
128  *
129  * IEEE80211_RADIOTAP_LOCK_QUALITY      uint16_t        unitless
130  *
131  *      Quality of Barker code lock. Unitless. Monotonically
132  *      nondecreasing with "better" lock strength. Called "Signal
133  *      Quality" in datasheets.  (Is there a standard way to measure
134  *      this?)
135  *
136  * IEEE80211_RADIOTAP_TX_ATTENUATION    uint16_t        unitless
137  *
138  *      Transmit power expressed as unitless distance from max
139  *      power set at factory calibration.  0 is max power.
140  *      Monotonically nondecreasing with lower power levels.
141  *
142  * IEEE80211_RADIOTAP_DB_TX_ATTENUATION uint16_t        decibels (dB)
143  *
144  *      Transmit power expressed as decibel distance from max power
145  *      set at factory calibration.  0 is max power.  Monotonically
146  *      nondecreasing with lower power levels.
147  *
148  * IEEE80211_RADIOTAP_DBM_TX_POWER      int8_t          decibels from
149  *                                                      one milliwatt (dBm)
150  *
151  *      Transmit power expressed as dBm (decibels from a 1 milliwatt
152  *      reference). This is the absolute power level measured at
153  *      the antenna port.
154  *
155  * IEEE80211_RADIOTAP_FLAGS             uint8_t         bitmap
156  *
157  *      Properties of transmitted and received frames. See flags
158  *      defined below.
159  *
160  * IEEE80211_RADIOTAP_ANTENNA           uint8_t         antenna index
161  *
162  *      Unitless indication of the Rx/Tx antenna for this packet.
163  *      The first antenna is antenna 0.
164  *
165  * IEEE80211_RADIOTAP_FCS           	uint32_t        data
166  *
167  *	FCS from frame in network byte order.
168  */
169 enum ieee80211_radiotap_type {
170 	IEEE80211_RADIOTAP_TSFT = 0,
171 	IEEE80211_RADIOTAP_FLAGS = 1,
172 	IEEE80211_RADIOTAP_RATE = 2,
173 	IEEE80211_RADIOTAP_CHANNEL = 3,
174 	IEEE80211_RADIOTAP_FHSS = 4,
175 	IEEE80211_RADIOTAP_DBM_ANTSIGNAL = 5,
176 	IEEE80211_RADIOTAP_DBM_ANTNOISE = 6,
177 	IEEE80211_RADIOTAP_LOCK_QUALITY = 7,
178 	IEEE80211_RADIOTAP_TX_ATTENUATION = 8,
179 	IEEE80211_RADIOTAP_DB_TX_ATTENUATION = 9,
180 	IEEE80211_RADIOTAP_DBM_TX_POWER = 10,
181 	IEEE80211_RADIOTAP_ANTENNA = 11,
182 	IEEE80211_RADIOTAP_DB_ANTSIGNAL = 12,
183 	IEEE80211_RADIOTAP_DB_ANTNOISE = 13,
184 	IEEE80211_RADIOTAP_EXT = 31,
185 };
186 
187 #ifndef _KERNEL
188 /* Channel flags. */
189 #define	IEEE80211_CHAN_TURBO	0x0010	/* Turbo channel */
190 #define	IEEE80211_CHAN_CCK	0x0020	/* CCK channel */
191 #define	IEEE80211_CHAN_OFDM	0x0040	/* OFDM channel */
192 #define	IEEE80211_CHAN_2GHZ	0x0080	/* 2 GHz spectrum channel. */
193 #define	IEEE80211_CHAN_5GHZ	0x0100	/* 5 GHz spectrum channel */
194 #define	IEEE80211_CHAN_PASSIVE	0x0200	/* Only passive scan allowed */
195 #define	IEEE80211_CHAN_DYN	0x0400	/* Dynamic CCK-OFDM channel */
196 #define	IEEE80211_CHAN_GFSK	0x0800	/* GFSK channel (FHSS PHY) */
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 #define	IEEE80211_RADIOTAP_F_DATAPAD	0x20	/* frame has padding between
215 						 * 802.11 header and payload
216 						 * (to 32-bit boundary)
217 						 */
218 #define	IEEE80211_RADIOTAP_F_BADFCS	0x40	/* does not pass FCS check */
219 
220 #endif /* _NET_IF_IEEE80211RADIOTAP_H_ */
221