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 1.3 2006/12/25 14:42:36 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. It must be
38  * rigidly defined (e.g., units for fields should be given),
39  * and easily extensible.
40  *
41  * The following is an 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 /*
64  * The radio capture header precedes the 802.11 header.
65  *
66  * Note well: all radiotap fields are little-endian.
67  */
68 struct ieee80211_radiotap_header {
69 	uint8_t		it_version;	/* Version 0. Only increases
70 					 * for drastic changes,
71 					 * introduction of compatible
72 					 * new fields does not count.
73 					 */
74 	uint8_t		it_pad;
75 	uint16_t	it_len;		/* length of the whole
76 					 * header in bytes, including
77 					 * it_version, it_pad,
78 					 * it_len, and data fields.
79 					 */
80 	uint32_t	it_present;	/* A bitmap telling which
81 					 * fields are present. Set bit 31
82 					 * (0x80000000) to extend the
83 					 * bitmap by another 32 bits.
84 					 * Additional extensions are made
85 					 * by setting bit 31.
86 					 */
87 } __packed;
88 
89 /*
90  * Name                                 Data type       Units
91  * ----                                 ---------       -----
92  *
93  * IEEE80211_RADIOTAP_TSFT              uint64_t        microseconds
94  *
95  *      Value in microseconds of the MAC's 64-bit 802.11 Time
96  *      Synchronization Function timer when the first bit of the
97  *      MPDU arrived at the MAC. For received frames, only.
98  *
99  * IEEE80211_RADIOTAP_CHANNEL           2 x uint16_t    MHz, bitmap
100  *
101  *      Tx/Rx frequency in MHz, followed by flags (see below).
102  *
103  * IEEE80211_RADIOTAP_FHSS              uint16_t        see below
104  *
105  *      For frequency-hopping radios, the hop set (first byte)
106  *      and pattern (second byte).
107  *
108  * IEEE80211_RADIOTAP_RATE              uint8_t         500kb/s
109  *
110  *      Tx/Rx data rate
111  *
112  * IEEE80211_RADIOTAP_DBM_ANTSIGNAL     int8_t          decibels from
113  *                                                      one milliwatt (dBm)
114  *
115  *      RF signal power at the antenna, decibel difference from
116  *      one milliwatt.
117  *
118  * IEEE80211_RADIOTAP_DBM_ANTNOISE      int8_t          decibels from
119  *                                                      one milliwatt (dBm)
120  *
121  *      RF noise power at the antenna, decibel difference from one
122  *      milliwatt.
123  *
124  * IEEE80211_RADIOTAP_DB_ANTSIGNAL      uint8_t         decibel (dB)
125  *
126  *      RF signal power at the antenna, decibel difference from an
127  *      arbitrary, fixed reference.
128  *
129  * IEEE80211_RADIOTAP_DB_ANTNOISE       uint8_t         decibel (dB)
130  *
131  *      RF noise power at the antenna, decibel difference from an
132  *      arbitrary, fixed reference point.
133  *
134  * IEEE80211_RADIOTAP_LOCK_QUALITY      uint16_t        unitless
135  *
136  *      Quality of Barker code lock. Unitless. Monotonically
137  *      nondecreasing with "better" lock strength. Called "Signal
138  *      Quality" in datasheets.  (Is there a standard way to measure
139  *      this?)
140  *
141  * IEEE80211_RADIOTAP_TX_ATTENUATION    uint16_t        unitless
142  *
143  *      Transmit power expressed as unitless distance from max
144  *      power set at factory calibration.  0 is max power.
145  *      Monotonically nondecreasing with lower power levels.
146  *
147  * IEEE80211_RADIOTAP_DB_TX_ATTENUATION uint16_t        decibels (dB)
148  *
149  *      Transmit power expressed as decibel distance from max power
150  *      set at factory calibration.  0 is max power.  Monotonically
151  *      nondecreasing with lower power levels.
152  *
153  * IEEE80211_RADIOTAP_DBM_TX_POWER      int8_t          decibels from
154  *                                                      one milliwatt (dBm)
155  *
156  *      Transmit power expressed as dBm (decibels from a 1 milliwatt
157  *      reference). This is the absolute power level measured at
158  *      the antenna port.
159  *
160  * IEEE80211_RADIOTAP_FLAGS             uint8_t         bitmap
161  *
162  *      Properties of transmitted and received frames. See flags
163  *      defined below.
164  *
165  * IEEE80211_RADIOTAP_ANTENNA           uint8_t         antenna index
166  *
167  *      Unitless indication of the Rx/Tx antenna for this packet.
168  *      The first antenna is antenna 0.
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_EXT = 31,
186 };
187 
188 #ifndef _KERNEL
189 /* Channel flags. */
190 #define	IEEE80211_CHAN_TURBO	0x0010	/* Turbo channel */
191 #define	IEEE80211_CHAN_CCK	0x0020	/* CCK channel */
192 #define	IEEE80211_CHAN_OFDM	0x0040	/* OFDM channel */
193 #define	IEEE80211_CHAN_2GHZ	0x0080	/* 2 GHz spectrum channel. */
194 #define	IEEE80211_CHAN_5GHZ	0x0100	/* 5 GHz spectrum channel */
195 #define	IEEE80211_CHAN_PASSIVE	0x0200	/* Only passive scan allowed */
196 #define	IEEE80211_CHAN_DYN	0x0400	/* Dynamic CCK-OFDM channel */
197 #define	IEEE80211_CHAN_GFSK	0x0800	/* GFSK channel (FHSS PHY) */
198 #endif /* !_KERNEL */
199 
200 /* For IEEE80211_RADIOTAP_FLAGS */
201 #define	IEEE80211_RADIOTAP_F_CFP	0x01	/* sent/received
202 						 * during CFP
203 						 */
204 #define	IEEE80211_RADIOTAP_F_SHORTPRE	0x02	/* sent/received
205 						 * with short
206 						 * preamble
207 						 */
208 #define	IEEE80211_RADIOTAP_F_WEP	0x04	/* sent/received
209 						 * with WEP encryption
210 						 */
211 #define	IEEE80211_RADIOTAP_F_FRAG	0x08	/* sent/received
212 						 * with fragmentation
213 						 */
214 #define	IEEE80211_RADIOTAP_F_FCS	0x10	/* frame includes FCS */
215 #define	IEEE80211_RADIOTAP_F_DATAPAD	0x20	/* frame has padding between
216 						 * 802.11 header and payload
217 						 * (to 32-bit boundary)
218 						 */
219 #define	IEEE80211_RADIOTAP_F_BADFCS	0x40	/* does not pass FCS check */
220 
221 #endif /* _NET_IF_IEEE80211RADIOTAP_H_ */
222