1/* 2 * Copyright (c) 2003, 2004 David Young. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 3. The name of David Young may not be used to endorse or promote 13 * products derived from this software without specific prior 14 * written permission. 15 * 16 * THIS SOFTWARE IS PROVIDED BY DAVID YOUNG ``AS IS'' AND ANY 17 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, 18 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A 19 * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL DAVID 20 * YOUNG BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 21 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED 22 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND 24 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 25 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 27 * OF SUCH DAMAGE. 28 */ 29 30/* 31 * Modifications to fit into the linux IEEE 802.11 stack, 32 * Mike Kershaw (dragorn@kismetwireless.net) 33 */ 34 35#ifndef IEEE80211RADIOTAP_H 36#define IEEE80211RADIOTAP_H 37 38#include <linux/if_ether.h> 39#include <linux/kernel.h> 40#include <asm/unaligned.h> 41 42/* Base version of the radiotap packet header data */ 43#define PKTHDR_RADIOTAP_VERSION 0 44 45/* A generic radio capture format is desirable. There is one for 46 * Linux, but it is neither rigidly defined (there were not even 47 * units given for some fields) nor easily extensible. 48 * 49 * I suggest the following extensible radio capture format. It is 50 * based on a bitmap indicating which fields are present. 51 * 52 * I am trying to describe precisely what the application programmer 53 * should expect in the following, and for that reason I tell the 54 * units and origin of each measurement (where it applies), or else I 55 * use sufficiently weaselly language ("is a monotonically nondecreasing 56 * function of...") that I cannot set false expectations for lawyerly 57 * readers. 58 */ 59 60/* 61 * The radio capture header precedes the 802.11 header. 62 * All data in the header is little endian on all platforms. 63 */ 64struct ieee80211_radiotap_header { 65 u8 it_version; /* Version 0. Only increases 66 * for drastic changes, 67 * introduction of compatible 68 * new fields does not count. 69 */ 70 u8 it_pad; 71 __le16 it_len; /* length of the whole 72 * header in bytes, including 73 * it_version, it_pad, 74 * it_len, and data fields. 75 */ 76 __le32 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 __le64 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 __le16 MHz, bitmap 95 * 96 * Tx/Rx frequency in MHz, followed by flags (see below). 97 * 98 * IEEE80211_RADIOTAP_FHSS __le16 see below 99 * 100 * For frequency-hopping radios, the hop set (first byte) 101 * and pattern (second byte). 102 * 103 * IEEE80211_RADIOTAP_RATE u8 500kb/s 104 * 105 * Tx/Rx data rate 106 * 107 * IEEE80211_RADIOTAP_DBM_ANTSIGNAL s8 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 s8 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 u8 decibel (dB) 120 * 121 * RF signal power at the antenna, decibel difference from an 122 * arbitrary, fixed reference. 123 * 124 * IEEE80211_RADIOTAP_DB_ANTNOISE u8 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 __le16 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 __le16 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 __le16 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 s8 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 u8 bitmap 156 * 157 * Properties of transmitted and received frames. See flags 158 * defined below. 159 * 160 * IEEE80211_RADIOTAP_ANTENNA u8 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_RX_FLAGS __le16 bitmap 166 * 167 * Properties of received frames. See flags defined below. 168 * 169 * IEEE80211_RADIOTAP_TX_FLAGS __le16 bitmap 170 * 171 * Properties of transmitted frames. See flags defined below. 172 * 173 * IEEE80211_RADIOTAP_RTS_RETRIES u8 data 174 * 175 * Number of rts retries a transmitted frame used. 176 * 177 * IEEE80211_RADIOTAP_DATA_RETRIES u8 data 178 * 179 * Number of unicast retries a transmitted frame used. 180 * 181 */ 182enum ieee80211_radiotap_type { 183 IEEE80211_RADIOTAP_TSFT = 0, 184 IEEE80211_RADIOTAP_FLAGS = 1, 185 IEEE80211_RADIOTAP_RATE = 2, 186 IEEE80211_RADIOTAP_CHANNEL = 3, 187 IEEE80211_RADIOTAP_FHSS = 4, 188 IEEE80211_RADIOTAP_DBM_ANTSIGNAL = 5, 189 IEEE80211_RADIOTAP_DBM_ANTNOISE = 6, 190 IEEE80211_RADIOTAP_LOCK_QUALITY = 7, 191 IEEE80211_RADIOTAP_TX_ATTENUATION = 8, 192 IEEE80211_RADIOTAP_DB_TX_ATTENUATION = 9, 193 IEEE80211_RADIOTAP_DBM_TX_POWER = 10, 194 IEEE80211_RADIOTAP_ANTENNA = 11, 195 IEEE80211_RADIOTAP_DB_ANTSIGNAL = 12, 196 IEEE80211_RADIOTAP_DB_ANTNOISE = 13, 197 IEEE80211_RADIOTAP_RX_FLAGS = 14, 198 IEEE80211_RADIOTAP_TX_FLAGS = 15, 199 IEEE80211_RADIOTAP_RTS_RETRIES = 16, 200 IEEE80211_RADIOTAP_DATA_RETRIES = 17, 201 202 /* valid in every it_present bitmap, even vendor namespaces */ 203 IEEE80211_RADIOTAP_RADIOTAP_NAMESPACE = 29, 204 IEEE80211_RADIOTAP_VENDOR_NAMESPACE = 30, 205 IEEE80211_RADIOTAP_EXT = 31 206}; 207 208/* Channel flags. */ 209#define IEEE80211_CHAN_TURBO 0x0010 /* Turbo channel */ 210#define IEEE80211_CHAN_CCK 0x0020 /* CCK channel */ 211#define IEEE80211_CHAN_OFDM 0x0040 /* OFDM channel */ 212#define IEEE80211_CHAN_2GHZ 0x0080 /* 2 GHz spectrum channel. */ 213#define IEEE80211_CHAN_5GHZ 0x0100 /* 5 GHz spectrum channel */ 214#define IEEE80211_CHAN_PASSIVE 0x0200 /* Only passive scan allowed */ 215#define IEEE80211_CHAN_DYN 0x0400 /* Dynamic CCK-OFDM channel */ 216#define IEEE80211_CHAN_GFSK 0x0800 /* GFSK channel (FHSS PHY) */ 217 218/* For IEEE80211_RADIOTAP_FLAGS */ 219#define IEEE80211_RADIOTAP_F_CFP 0x01 /* sent/received 220 * during CFP 221 */ 222#define IEEE80211_RADIOTAP_F_SHORTPRE 0x02 /* sent/received 223 * with short 224 * preamble 225 */ 226#define IEEE80211_RADIOTAP_F_WEP 0x04 /* sent/received 227 * with WEP encryption 228 */ 229#define IEEE80211_RADIOTAP_F_FRAG 0x08 /* sent/received 230 * with fragmentation 231 */ 232#define IEEE80211_RADIOTAP_F_FCS 0x10 /* frame includes FCS */ 233#define IEEE80211_RADIOTAP_F_DATAPAD 0x20 /* frame has padding between 234 * 802.11 header and payload 235 * (to 32-bit boundary) 236 */ 237#define IEEE80211_RADIOTAP_F_BADFCS 0x40 /* bad FCS */ 238 239/* For IEEE80211_RADIOTAP_RX_FLAGS */ 240#define IEEE80211_RADIOTAP_F_RX_BADPLCP 0x0002 /* frame has bad PLCP */ 241 242/* For IEEE80211_RADIOTAP_TX_FLAGS */ 243#define IEEE80211_RADIOTAP_F_TX_FAIL 0x0001 /* failed due to excessive 244 * retries */ 245#define IEEE80211_RADIOTAP_F_TX_CTS 0x0002 /* used cts 'protection' */ 246#define IEEE80211_RADIOTAP_F_TX_RTS 0x0004 /* used rts/cts handshake */ 247 248/* Ugly macro to convert literal channel numbers into their mhz equivalents 249 * There are certianly some conditions that will break this (like feeding it '30') 250 * but they shouldn't arise since nothing talks on channel 30. */ 251#define ieee80211chan2mhz(x) \ 252 (((x) <= 14) ? \ 253 (((x) == 14) ? 2484 : ((x) * 5) + 2407) : \ 254 ((x) + 1000) * 5) 255 256/* helpers */ 257static inline int ieee80211_get_radiotap_len(unsigned char *data) 258{ 259 struct ieee80211_radiotap_header *hdr = 260 (struct ieee80211_radiotap_header *)data; 261 262 return get_unaligned_le16(&hdr->it_len); 263} 264 265#endif /* IEEE80211_RADIOTAP_H */ 266