* 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.

 */

/*

 * Modifications to fit into the linux IEEE 802.11 stack,

 * Mike Kershaw (dragorn@kismetwireless.net)

 */

#ifndef IEEE80211RADIOTAP_H

#define IEEE80211RADIOTAP_H

#include <linux/if_ether.h>

#include <linux/kernel.h>

#include <asm/unaligned.h>

/* Base version of the radiotap packet header data */

#define PKTHDR_RADIOTAP_VERSION		0

/* 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.

 */

 * All data in the header is little endian on all platforms.

 */

struct ieee80211_radiotap_header {

	u8 it_version;		/* Version 0. Only increases

				 * for drastic changes,

				 * introduction of compatible

				 * new fields does not count.

				 */

	u8 it_pad;

	__le16 it_len;		/* length of the whole

				 * header in bytes, including

				 * it_version, it_pad,

				 * it_len, and data fields.

				 */

	__le32 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.

				 */

};

/* Name                                 Data type    Units

 * ----                                 ---------    -----

 *

 * IEEE80211_RADIOTAP_TSFT              __le64       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 __le16   MHz, bitmap

 *

 *      Tx/Rx frequency in MHz, followed by flags (see below).

 *

 * IEEE80211_RADIOTAP_FHSS              __le16       see below

 *

 *      For frequency-hopping radios, the hop set (first byte)

 *      and pattern (second byte).

 *

 * IEEE80211_RADIOTAP_RATE              u8           500kb/s

 *

 *      Tx/Rx data rate

 *

 * IEEE80211_RADIOTAP_DBM_ANTSIGNAL     s8           decibels from

 *                                                   one milliwatt (dBm)

 *

 *      RF signal power at the antenna, decibel difference from

 *      one milliwatt.

 *

 * IEEE80211_RADIOTAP_DBM_ANTNOISE      s8           decibels from

 *                                                   one milliwatt (dBm)

 *

 *      RF noise power at the antenna, decibel difference from one

 *      milliwatt.

 *

 * IEEE80211_RADIOTAP_DB_ANTSIGNAL      u8           decibel (dB)

 *

 *      RF signal power at the antenna, decibel difference from an

 *      arbitrary, fixed reference.

 *

 * IEEE80211_RADIOTAP_DB_ANTNOISE       u8           decibel (dB)

 *

 *      RF noise power at the antenna, decibel difference from an

 *      arbitrary, fixed reference point.

 *

 * IEEE80211_RADIOTAP_LOCK_QUALITY      __le16       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    __le16       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 __le16       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      s8           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             u8           bitmap

 *

 *      Properties of transmitted and received frames. See flags

 *      defined below.

 *

 * IEEE80211_RADIOTAP_ANTENNA           u8           antenna index

 *

 *      Unitless indication of the Rx/Tx antenna for this packet.

 *      The first antenna is antenna 0.

 *

 * IEEE80211_RADIOTAP_RX_FLAGS          __le16       bitmap

 *

 *     Properties of received frames. See flags defined below.

 *

 * IEEE80211_RADIOTAP_TX_FLAGS          __le16       bitmap

 *

 *     Properties of transmitted frames. See flags defined below.

 *

 * IEEE80211_RADIOTAP_RTS_RETRIES       u8           data

 *

 *     Number of rts retries a transmitted frame used.

 *

 * IEEE80211_RADIOTAP_DATA_RETRIES      u8           data

 *

 *     Number of unicast retries a transmitted frame used.

 *

 */

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_RX_FLAGS = 14,

	IEEE80211_RADIOTAP_TX_FLAGS = 15,

	IEEE80211_RADIOTAP_RTS_RETRIES = 16,

	IEEE80211_RADIOTAP_DATA_RETRIES = 17,

	IEEE80211_RADIOTAP_EXT = 31

};

/* Channel flags. */

#define	IEEE80211_CHAN_TURBO	0x0010	/* Turbo channel */

#define	IEEE80211_CHAN_CCK	0x0020	/* CCK channel */

#define	IEEE80211_CHAN_OFDM	0x0040	/* OFDM channel */

#define	IEEE80211_CHAN_2GHZ	0x0080	/* 2 GHz spectrum channel. */

#define	IEEE80211_CHAN_5GHZ	0x0100	/* 5 GHz spectrum channel */

#define	IEEE80211_CHAN_PASSIVE	0x0200	/* Only passive scan allowed */

#define	IEEE80211_CHAN_DYN	0x0400	/* Dynamic CCK-OFDM channel */

#define	IEEE80211_CHAN_GFSK	0x0800	/* GFSK channel (FHSS PHY) */

/* 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

						 */

#define	IEEE80211_RADIOTAP_F_FCS	0x10	/* frame includes FCS */

#define	IEEE80211_RADIOTAP_F_DATAPAD	0x20	/* frame has padding between

						 * 802.11 header and payload

						 * (to 32-bit boundary)

						 */

/* For IEEE80211_RADIOTAP_RX_FLAGS */

#define IEEE80211_RADIOTAP_F_RX_BADFCS	0x0001	/* frame failed crc check */

/* For IEEE80211_RADIOTAP_TX_FLAGS */

#define IEEE80211_RADIOTAP_F_TX_FAIL	0x0001	/* failed due to excessive

						 * retries */

#define IEEE80211_RADIOTAP_F_TX_CTS	0x0002	/* used cts 'protection' */

#define IEEE80211_RADIOTAP_F_TX_RTS	0x0004	/* used rts/cts handshake */

/* Ugly macro to convert literal channel numbers into their mhz equivalents

 * There are certianly some conditions that will break this (like feeding it '30')

 * but they shouldn't arise since nothing talks on channel 30. */

#define ieee80211chan2mhz(x) \

	(((x) <= 14) ? \

	(((x) == 14) ? 2484 : ((x) * 5) + 2407) : \

	((x) + 1000) * 5)

/* helpers */

static inline int ieee80211_get_radiotap_len(unsigned char *data)

{

	struct ieee80211_radiotap_header *hdr =

		(struct ieee80211_radiotap_header *)data;

	return get_unaligned_le16(&hdr->it_len);

}

#endif				/* IEEE80211_RADIOTAP_H */