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/* $OpenBSD: ieee80211_radiotap.h,v 1.8 2006/06/23 21:34:15 reyk Exp $ */
/* $FreeBSD: src/sys/net80211/ieee80211_radiotap.h,v 1.3 2004/04/05 22:13:21 sam Exp $ */
/* $NetBSD: ieee80211_radiotap.h,v 1.9 2004/06/06 04:13:28 dyoung Exp $ */
/*-
* Copyright (c) 2003, 2004 David Young. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of David Young may not be used to endorse or promote
* products derived from this software without specific prior
* written permission.
*
* THIS SOFTWARE IS PROVIDED BY DAVID YOUNG ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
* PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL DAVID
* YOUNG BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
* TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
* OF SUCH DAMAGE.
*/
#ifndef _NET_IF_IEEE80211RADIOTAP_H_
#define _NET_IF_IEEE80211RADIOTAP_H_
/* A generic radio capture format is desirable. There is one for
* Linux, but it is neither rigidly defined (there were not even
* units given for some fields) nor easily extensible.
*
* I suggest the following extensible radio capture format. It is
* based on a bitmap indicating which fields are present.
*
* I am trying to describe precisely what the application programmer
* should expect in the following, and for that reason I tell the
* units and origin of each measurement (where it applies), or else I
* use sufficiently weaselly language ("is a monotonically nondecreasing
* function of...") that I cannot set false expectations for lawyerly
* readers.
*/
/* XXX tcpdump/libpcap do not tolerate variable-length headers,
* yet, so we pad every radiotap header to 64 bytes. Ugh.
*/
#define IEEE80211_RADIOTAP_HDRLEN 64
/* The radio capture header precedes the 802.11 header. */
struct ieee80211_radiotap_header {
u_int8_t it_version; /* Version 0. Only increases
* for drastic changes,
* introduction of compatible
* new fields does not count.
*/
u_int8_t it_pad;
u_int16_t it_len; /* length of the whole
* header in bytes, including
* it_version, it_pad,
* it_len, and data fields.
*/
u_int32_t it_present; /* A bitmap telling which
* fields are present. Set bit 31
* (0x80000000) to extend the
* bitmap by another 32 bits.
* Additional extensions are made
* by setting bit 31.
*/
} __packed;
/* Name Data type Units
* ---- --------- -----
*
* IEEE80211_RADIOTAP_TSFT u_int64_t microseconds
*
* Value in microseconds of the MAC's 64-bit 802.11 Time
* Synchronization Function timer when the first bit of the
* MPDU arrived at the MAC. For received frames, only.
*
* IEEE80211_RADIOTAP_CHANNEL 2 x u_int16_t MHz, bitmap
*
* Tx/Rx frequency in MHz, followed by flags (see below).
*
* IEEE80211_RADIOTAP_FHSS u_int16_t see below
*
* For frequency-hopping radios, the hop set (first byte)
* and pattern (second byte).
*
* IEEE80211_RADIOTAP_RATE u_int8_t 500kb/s
*
* Tx/Rx data rate
*
* IEEE80211_RADIOTAP_DBM_ANTSIGNAL int8_t decibels from
* one milliwatt (dBm)
*
* RF signal power at the antenna, decibel difference from
* one milliwatt.
*
* IEEE80211_RADIOTAP_DBM_ANTNOISE int8_t decibels from
* one milliwatt (dBm)
*
* RF noise power at the antenna, decibel difference from one
* milliwatt.
*
* IEEE80211_RADIOTAP_DB_ANTSIGNAL u_int8_t decibel (dB)
*
* RF signal power at the antenna, decibel difference from an
* arbitrary, fixed reference.
*
* IEEE80211_RADIOTAP_DB_ANTNOISE u_int8_t decibel (dB)
*
* RF noise power at the antenna, decibel difference from an
* arbitrary, fixed reference point.
*
* IEEE80211_RADIOTAP_BARKER_CODE_LOCK u_int16_t unitless
*
* Quality of Barker code lock. Unitless. Monotonically
* nondecreasing with "better" lock strength. Called "Signal
* Quality" in datasheets. (Is there a standard way to measure
* this?)
*
* IEEE80211_RADIOTAP_TX_ATTENUATION u_int16_t unitless
*
* Transmit power expressed as unitless distance from max
* power set at factory calibration. 0 is max power.
* Monotonically nondecreasing with lower power levels.
*
* IEEE80211_RADIOTAP_DB_TX_ATTENUATION u_int16_t decibels (dB)
*
* Transmit power expressed as decibel distance from max power
* set at factory calibration. 0 is max power. Monotonically
* nondecreasing with lower power levels.
*
* IEEE80211_RADIOTAP_DBM_TX_POWER int8_t decibels from
* one milliwatt (dBm)
*
* Transmit power expressed as dBm (decibels from a 1 milliwatt
* reference). This is the absolute power level measured at
* the antenna port.
*
* IEEE80211_RADIOTAP_FLAGS u_int8_t bitmap
*
* Properties of transmitted and received frames. See flags
* defined below.
*
* IEEE80211_RADIOTAP_ANTENNA u_int8_t antenna index
*
* Unitless indication of the Rx/Tx antenna for this packet.
* The first antenna is antenna 0.
*
* IEEE80211_RADIOTAP_FCS u_int32_t data
*
* FCS from frame in network byte order.
*
* IEEE80211_RADIOTAP_HWQUEUE u_int8_t data
*
* A specific hardware queue (used by WME)
*
* IEEE80211_RADIOTAP_RSSI 2x u_int8_t RSSI, max RSSI
*
* A relative Received Signal Strength Index
*/
enum ieee80211_radiotap_type {
IEEE80211_RADIOTAP_TSFT = 0,
IEEE80211_RADIOTAP_FLAGS = 1,
IEEE80211_RADIOTAP_RATE = 2,
IEEE80211_RADIOTAP_CHANNEL = 3,
IEEE80211_RADIOTAP_FHSS = 4,
IEEE80211_RADIOTAP_DBM_ANTSIGNAL = 5,
IEEE80211_RADIOTAP_DBM_ANTNOISE = 6,
IEEE80211_RADIOTAP_LOCK_QUALITY = 7,
IEEE80211_RADIOTAP_TX_ATTENUATION = 8,
IEEE80211_RADIOTAP_DB_TX_ATTENUATION = 9,
IEEE80211_RADIOTAP_DBM_TX_POWER = 10,
IEEE80211_RADIOTAP_ANTENNA = 11,
IEEE80211_RADIOTAP_DB_ANTSIGNAL = 12,
IEEE80211_RADIOTAP_DB_ANTNOISE = 13,
IEEE80211_RADIOTAP_FCS = 14,
IEEE80211_RADIOTAP_HWQUEUE = 15,
IEEE80211_RADIOTAP_RSSI = 16,
IEEE80211_RADIOTAP_EXT = 31
};
/* For IEEE80211_RADIOTAP_FLAGS */
#define IEEE80211_RADIOTAP_F_CFP 0x01 /* sent/received
* during CFP
*/
#define IEEE80211_RADIOTAP_F_SHORTPRE 0x02 /* sent/received
* with short
* preamble
*/
#define IEEE80211_RADIOTAP_F_WEP 0x04 /* sent/received
* with WEP encryption
*/
#define IEEE80211_RADIOTAP_F_FRAG 0x08 /* sent/received
* with fragmentation
*/
#endif /* _NET_IF_IEEE80211RADIOTAP_H_ */
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