The Design and Implementation of the FreeBSD Operating System, Second Edition
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FreeBSD/Linux Kernel Cross Reference
sys/net80211/ieee80211_radiotap.h

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    1 /* $FreeBSD: releng/12.0/sys/net80211/ieee80211_radiotap.h 326272 2017-11-27 15:23:17Z pfg $ */
    2 /* $NetBSD: ieee80211_radiotap.h,v 1.16 2007/01/06 05:51:15 dyoung Exp $ */
    3 
    4 /*-
    5  * SPDX-License-Identifier: BSD-3-Clause
    6  *
    7  * Copyright (c) 2003, 2004 David Young.  All rights reserved.
    8  *
    9  * Redistribution and use in source and binary forms, with or without
   10  * modification, are permitted provided that the following conditions
   11  * are met:
   12  * 1. Redistributions of source code must retain the above copyright
   13  *    notice, this list of conditions and the following disclaimer.
   14  * 2. Redistributions in binary form must reproduce the above copyright
   15  *    notice, this list of conditions and the following disclaimer in the
   16  *    documentation and/or other materials provided with the distribution.
   17  * 3. The name of David Young may not be used to endorse or promote
   18  *    products derived from this software without specific prior
   19  *    written permission.
   20  *
   21  * THIS SOFTWARE IS PROVIDED BY DAVID YOUNG ``AS IS'' AND ANY
   22  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
   23  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
   24  * PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL DAVID
   25  * YOUNG BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
   26  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
   27  * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
   28  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
   29  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
   30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
   32  * OF SUCH DAMAGE.
   33  */
   34 #ifndef _NET80211_IEEE80211_RADIOTAP_H_
   35 #define _NET80211_IEEE80211_RADIOTAP_H_
   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 #define IEEE80211_RADIOTAP_HDRLEN       64      /* XXX deprecated */
   58 
   59 struct ieee80211_radiotap_vendor_header {
   60         uint8_t         vh_oui[3];      /* 3 byte vendor OUI */
   61         uint8_t         vh_sub_ns;      /* Sub namespace of this section */
   62         uint16_t        vh_skip_len;    /* Length of this vendor section */
   63 } __packed;
   64 
   65 /*
   66  * The radio capture header precedes the 802.11 header.
   67  *
   68  * Note well: all radiotap fields are little-endian.
   69  */
   70 struct ieee80211_radiotap_header {
   71         uint8_t         it_version;     /* Version 0. Only increases
   72                                          * for drastic changes,
   73                                          * introduction of compatible
   74                                          * new fields does not count.
   75                                          */
   76         uint8_t         it_pad;
   77         uint16_t        it_len;         /* length of the whole
   78                                          * header in bytes, including
   79                                          * it_version, it_pad,
   80                                          * it_len, and data fields.
   81                                          */
   82         uint32_t        it_present;     /* A bitmap telling which
   83                                          * fields are present. Set bit 31
   84                                          * (0x80000000) to extend the
   85                                          * bitmap by another 32 bits.
   86                                          * Additional extensions are made
   87                                          * by setting bit 31.
   88                                          */
   89 } __packed;
   90 
   91 /*
   92  * Name                                 Data type       Units
   93  * ----                                 ---------       -----
   94  *
   95  * IEEE80211_RADIOTAP_TSFT              uint64_t        microseconds
   96  *
   97  *      Value in microseconds of the MAC's 64-bit 802.11 Time
   98  *      Synchronization Function timer when the first bit of the
   99  *      MPDU arrived at the MAC. For received frames, only.
  100  *
  101  * IEEE80211_RADIOTAP_CHANNEL           2 x uint16_t    MHz, bitmap
  102  *
  103  *      Tx/Rx frequency in MHz, followed by flags (see below).
  104  *
  105  * IEEE80211_RADIOTAP_FHSS              uint16_t        see below
  106  *
  107  *      For frequency-hopping radios, the hop set (first byte)
  108  *      and pattern (second byte).
  109  *
  110  * IEEE80211_RADIOTAP_RATE              uint8_t         500kb/s or index
  111  *
  112  *      Tx/Rx data rate.  If bit 0x80 is set then it represents an
  113  *      an MCS index and not an IEEE rate.
  114  *
  115  * IEEE80211_RADIOTAP_DBM_ANTSIGNAL     int8_t          decibels from
  116  *                                                      one milliwatt (dBm)
  117  *
  118  *      RF signal power at the antenna, decibel difference from
  119  *      one milliwatt.
  120  *
  121  * IEEE80211_RADIOTAP_DBM_ANTNOISE      int8_t          decibels from
  122  *                                                      one milliwatt (dBm)
  123  *
  124  *      RF noise power at the antenna, decibel difference from one
  125  *      milliwatt.
  126  *
  127  * IEEE80211_RADIOTAP_DB_ANTSIGNAL      uint8_t         decibel (dB)
  128  *
  129  *      RF signal power at the antenna, decibel difference from an
  130  *      arbitrary, fixed reference.
  131  *
  132  * IEEE80211_RADIOTAP_DB_ANTNOISE       uint8_t         decibel (dB)
  133  *
  134  *      RF noise power at the antenna, decibel difference from an
  135  *      arbitrary, fixed reference point.
  136  *
  137  * IEEE80211_RADIOTAP_LOCK_QUALITY      uint16_t        unitless
  138  *
  139  *      Quality of Barker code lock. Unitless. Monotonically
  140  *      nondecreasing with "better" lock strength. Called "Signal
  141  *      Quality" in datasheets.  (Is there a standard way to measure
  142  *      this?)
  143  *
  144  * IEEE80211_RADIOTAP_TX_ATTENUATION    uint16_t        unitless
  145  *
  146  *      Transmit power expressed as unitless distance from max
  147  *      power set at factory calibration.  0 is max power.
  148  *      Monotonically nondecreasing with lower power levels.
  149  *
  150  * IEEE80211_RADIOTAP_DB_TX_ATTENUATION uint16_t        decibels (dB)
  151  *
  152  *      Transmit power expressed as decibel distance from max power
  153  *      set at factory calibration.  0 is max power.  Monotonically
  154  *      nondecreasing with lower power levels.
  155  *
  156  * IEEE80211_RADIOTAP_DBM_TX_POWER      int8_t          decibels from
  157  *                                                      one milliwatt (dBm)
  158  *
  159  *      Transmit power expressed as dBm (decibels from a 1 milliwatt
  160  *      reference). This is the absolute power level measured at
  161  *      the antenna port.
  162  *
  163  * IEEE80211_RADIOTAP_FLAGS             uint8_t         bitmap
  164  *
  165  *      Properties of transmitted and received frames. See flags
  166  *      defined below.
  167  *
  168  * IEEE80211_RADIOTAP_ANTENNA           uint8_t         antenna index
  169  *
  170  *      Unitless indication of the Rx/Tx antenna for this packet.
  171  *      The first antenna is antenna 0.
  172  *
  173  * IEEE80211_RADIOTAP_XCHANNEL          uint32_t        bitmap
  174  *                                      uint16_t        MHz
  175  *                                      uint8_t         channel number
  176  *                                      int8_t          .5 dBm
  177  *
  178  *      Extended channel specification: flags (see below) followed by
  179  *      frequency in MHz, the corresponding IEEE channel number, and
  180  *      finally the maximum regulatory transmit power cap in .5 dBm
  181  *      units.  This property supersedes IEEE80211_RADIOTAP_CHANNEL
  182  *      and only one of the two should be present.
  183  * IEEE80211_RADIOTAP_RX_FLAGS          guint16       bitmap
  184  *
  185  *     Properties of received frames. See flags defined below.
  186  *
  187  * IEEE80211_RADIOTAP_TX_FLAGS          guint16       bitmap
  188  *
  189  *     Properties of transmitted frames. See flags defined below.
  190  *
  191  * IEEE80211_RADIOTAP_RTS_RETRIES       u8           data
  192  *
  193  *     Number of rts retries a transmitted frame used.
  194  *
  195  * IEEE80211_RADIOTAP_DATA_RETRIES      u8           data
  196  *
  197  *     Number of unicast retries a transmitted frame used.
  198  *
  199  * IEEE80211_RADIOTAP_MCS       u8, u8, u8              unitless
  200  *
  201  *     Contains a bitmap of known fields/flags, the flags, and
  202  *     the MCS index.
  203  *
  204  * IEEE80211_RADIOTAP_AMPDU_STATUS      u32, u16, u8, u8        unitlesss
  205  *
  206  *      Contains the AMPDU information for the subframe.
  207  */
  208 enum ieee80211_radiotap_type {
  209         IEEE80211_RADIOTAP_TSFT = 0,
  210         IEEE80211_RADIOTAP_FLAGS = 1,
  211         IEEE80211_RADIOTAP_RATE = 2,
  212         IEEE80211_RADIOTAP_CHANNEL = 3,
  213         IEEE80211_RADIOTAP_FHSS = 4,
  214         IEEE80211_RADIOTAP_DBM_ANTSIGNAL = 5,
  215         IEEE80211_RADIOTAP_DBM_ANTNOISE = 6,
  216         IEEE80211_RADIOTAP_LOCK_QUALITY = 7,
  217         IEEE80211_RADIOTAP_TX_ATTENUATION = 8,
  218         IEEE80211_RADIOTAP_DB_TX_ATTENUATION = 9,
  219         IEEE80211_RADIOTAP_DBM_TX_POWER = 10,
  220         IEEE80211_RADIOTAP_ANTENNA = 11,
  221         IEEE80211_RADIOTAP_DB_ANTSIGNAL = 12,
  222         IEEE80211_RADIOTAP_DB_ANTNOISE = 13,
  223         /*
  224          * 14-17 are from Linux, they overlap the netbsd-specific
  225          * fields.
  226          */
  227         IEEE80211_RADIOTAP_RX_FLAGS = 14,
  228         IEEE80211_RADIOTAP_TX_FLAGS = 15,
  229         IEEE80211_RADIOTAP_RTS_RETRIES = 16,
  230         IEEE80211_RADIOTAP_DATA_RETRIES = 17,
  231 
  232         IEEE80211_RADIOTAP_XCHANNEL = 18,
  233         IEEE80211_RADIOTAP_MCS = 19,
  234         IEEE80211_RADIOTAP_AMPDU_STATUS = 20,
  235         IEEE80211_RADIOTAP_VHT = 21,
  236 
  237         IEEE80211_RADIOTAP_RADIOTAP_NAMESPACE = 29,
  238         IEEE80211_RADIOTAP_VENDOREXT = 30,
  239         IEEE80211_RADIOTAP_EXT = 31,
  240 };
  241 
  242 #ifndef _KERNEL
  243 /* channel attributes */
  244 #define IEEE80211_CHAN_TURBO    0x00000010 /* Turbo channel */
  245 #define IEEE80211_CHAN_CCK      0x00000020 /* CCK channel */
  246 #define IEEE80211_CHAN_OFDM     0x00000040 /* OFDM channel */
  247 #define IEEE80211_CHAN_2GHZ     0x00000080 /* 2 GHz spectrum channel. */
  248 #define IEEE80211_CHAN_5GHZ     0x00000100 /* 5 GHz spectrum channel */
  249 #define IEEE80211_CHAN_PASSIVE  0x00000200 /* Only passive scan allowed */
  250 #define IEEE80211_CHAN_DYN      0x00000400 /* Dynamic CCK-OFDM channel */
  251 #define IEEE80211_CHAN_GFSK     0x00000800 /* GFSK channel (FHSS PHY) */
  252 #define IEEE80211_CHAN_GSM      0x00001000 /* 900 MHz spectrum channel */
  253 #define IEEE80211_CHAN_STURBO   0x00002000 /* 11a static turbo channel only */
  254 #define IEEE80211_CHAN_HALF     0x00004000 /* Half rate channel */
  255 #define IEEE80211_CHAN_QUARTER  0x00008000 /* Quarter rate channel */
  256 #endif /* !_KERNEL */
  257 
  258 /* For IEEE80211_RADIOTAP_FLAGS */
  259 #define IEEE80211_RADIOTAP_F_CFP        0x01    /* sent/received
  260                                                  * during CFP
  261                                                  */
  262 #define IEEE80211_RADIOTAP_F_SHORTPRE   0x02    /* sent/received
  263                                                  * with short
  264                                                  * preamble
  265                                                  */
  266 #define IEEE80211_RADIOTAP_F_WEP        0x04    /* sent/received
  267                                                  * with WEP encryption
  268                                                  */
  269 #define IEEE80211_RADIOTAP_F_FRAG       0x08    /* sent/received
  270                                                  * with fragmentation
  271                                                  */
  272 #define IEEE80211_RADIOTAP_F_FCS        0x10    /* frame includes FCS */
  273 #define IEEE80211_RADIOTAP_F_DATAPAD    0x20    /* frame has padding between
  274                                                  * 802.11 header and payload
  275                                                  * (to 32-bit boundary)
  276                                                  */
  277 #define IEEE80211_RADIOTAP_F_BADFCS     0x40    /* does not pass FCS check */
  278 #define IEEE80211_RADIOTAP_F_SHORTGI    0x80    /* HT short GI */
  279 
  280 /* For IEEE80211_RADIOTAP_RX_FLAGS */
  281 #define IEEE80211_RADIOTAP_F_RX_BADPLCP 0x0002  /* bad PLCP */
  282 
  283 /* For IEEE80211_RADIOTAP_TX_FLAGS */
  284 #define IEEE80211_RADIOTAP_F_TX_FAIL    0x0001  /* failed due to excessive
  285                                                  * retries */
  286 #define IEEE80211_RADIOTAP_F_TX_CTS     0x0002  /* used cts 'protection' */
  287 #define IEEE80211_RADIOTAP_F_TX_RTS     0x0004  /* used rts/cts handshake */
  288 
  289 
  290 /* For IEEE80211_RADIOTAP_MCS */
  291 #define IEEE80211_RADIOTAP_MCS_HAVE_BW          0x01
  292 #define IEEE80211_RADIOTAP_MCS_HAVE_MCS         0x02
  293 #define IEEE80211_RADIOTAP_MCS_HAVE_GI          0x04
  294 #define IEEE80211_RADIOTAP_MCS_HAVE_FMT         0x08
  295 #define IEEE80211_RADIOTAP_MCS_HAVE_FEC         0x10
  296 #define IEEE80211_RADIOTAP_MCS_HAVE_STBC        0x20
  297 #define IEEE80211_RADIOTAP_MCS_HAVE_NESS        0x40
  298 #define IEEE80211_RADIOTAP_MCS_NESS_BIT1        0x80
  299 
  300 #define IEEE80211_RADIOTAP_MCS_BW_MASK          0x03
  301 #define     IEEE80211_RADIOTAP_MCS_BW_20        0
  302 #define     IEEE80211_RADIOTAP_MCS_BW_40        1
  303 #define  IEEE80211_RADIOTAP_MCS_BW_20L          2
  304 #define     IEEE80211_RADIOTAP_MCS_BW_20U       3
  305 #define IEEE80211_RADIOTAP_MCS_SGI              0x04
  306 #define IEEE80211_RADIOTAP_MCS_FMT_GF           0x08
  307 #define IEEE80211_RADIOTAP_MCS_FEC_LDPC         0x10
  308 #define IEEE80211_RADIOTAP_MCS_STBC_MASK        0x60
  309 #define IEEE80211_RADIOTAP_MCS_STBC_SHIFT       5
  310 #define     IEEE80211_RADIOTAP_MCS_STBC_1       1
  311 #define     IEEE80211_RADIOTAP_MCS_STBC_2       2
  312 #define     IEEE80211_RADIOTAP_MCS_STBC_3       3
  313 #define IEEE80211_RADIOTAP_MCS_NESS_BIT0        0x80
  314 
  315 /* For IEEE80211_RADIOTAP_AMPDU_STATUS */
  316 #define IEEE80211_RADIOTAP_AMPDU_REPORT_ZEROLEN         0x0001
  317 #define IEEE80211_RADIOTAP_AMPDU_IS_ZEROLEN             0x0002
  318 #define IEEE80211_RADIOTAP_AMPDU_LAST_KNOWN             0x0004
  319 #define IEEE80211_RADIOTAP_AMPDU_IS_LAST                0x0008
  320 #define IEEE80211_RADIOTAP_AMPDU_DELIM_CRC_ERR          0x0010
  321 #define IEEE80211_RADIOTAP_AMPDU_DELIM_CRC_KNOWN        0x0020
  322 
  323 /* For IEEE80211_RADIOTAP_VHT */
  324 #define IEEE80211_RADIOTAP_VHT_HAVE_STBC        0x0001
  325 #define IEEE80211_RADIOTAP_VHT_HAVE_TXOP_PS     0x0002
  326 #define IEEE80211_RADIOTAP_VHT_HAVE_GI          0x0004
  327 #define IEEE80211_RADIOTAP_VHT_HAVE_SGI_NSYM_DA 0x0008
  328 #define IEEE80211_RADIOTAP_VHT_HAVE_LDPC_EXTRA  0x0010
  329 #define IEEE80211_RADIOTAP_VHT_HAVE_BF          0x0020
  330 #define IEEE80211_RADIOTAP_VHT_HAVE_BW          0x0040
  331 #define IEEE80211_RADIOTAP_VHT_HAVE_GID         0x0080
  332 #define IEEE80211_RADIOTAP_VHT_HAVE_PAID        0x0100
  333 #define IEEE80211_RADIOTAP_VHT_STBC             0x01
  334 #define IEEE80211_RADIOTAP_VHT_TXOP_PS          0x02
  335 #define IEEE80211_RADIOTAP_VHT_SGI              0x04
  336 #define IEEE80211_RADIOTAP_VHT_SGI_NSYM_DA      0x08
  337 #define IEEE80211_RADIOTAP_VHT_LDPC_EXTRA       0x10
  338 #define IEEE80211_RADIOTAP_VHT_BF               0x20
  339 #define IEEE80211_RADIOTAP_VHT_NSS              0x0f
  340 #define IEEE80211_RADIOTAP_VHT_MCS              0xf0
  341 #define IEEE80211_RADIOTAP_VHT_CODING_LDPC      0x01
  342 
  343 #define IEEE80211_RADIOTAP_VHT_BW_MASK          0x1f
  344 #define IEEE80211_RADIOTAP_VHT_BW_20            IEEE80211_RADIOTAP_MCS_BW_20
  345 #define IEEE80211_RADIOTAP_VHT_BW_40            IEEE80211_RADIOTAP_MCS_BW_40
  346 #define IEEE80211_RADIOTAP_VHT_BW_20L           IEEE80211_RADIOTAP_MCS_BW_20L
  347 #define IEEE80211_RADIOTAP_VHT_BW_20U           IEEE80211_RADIOTAP_MCS_BW_20U
  348 #define IEEE80211_RADIOTAP_VHT_BW_80            4
  349 #define IEEE80211_RADIOTAP_VHT_BW_40L           5
  350 #define IEEE80211_RADIOTAP_VHT_BW_40U           6
  351 #define IEEE80211_RADIOTAP_VHT_BW_20LL          7
  352 #define IEEE80211_RADIOTAP_VHT_BW_20LU          8
  353 #define IEEE80211_RADIOTAP_VHT_BW_20UL          9
  354 #define IEEE80211_RADIOTAP_VHT_BW_20UU          10
  355 #define IEEE80211_RADIOTAP_VHT_BW_160           11
  356 #define IEEE80211_RADIOTAP_VHT_BW_80L           12
  357 #define IEEE80211_RADIOTAP_VHT_BW_80U           13
  358 #define IEEE80211_RADIOTAP_VHT_BW_40LL          14
  359 #define IEEE80211_RADIOTAP_VHT_BW_40LU          15
  360 #define IEEE80211_RADIOTAP_VHT_BW_40UL          16
  361 #define IEEE80211_RADIOTAP_VHT_BW_40UU          17
  362 #define IEEE80211_RADIOTAP_VHT_BW_20LLL         18
  363 #define IEEE80211_RADIOTAP_VHT_BW_20LLU         19
  364 #define IEEE80211_RADIOTAP_VHT_BW_20LUL         20
  365 #define IEEE80211_RADIOTAP_VHT_BW_20LUU         21
  366 #define IEEE80211_RADIOTAP_VHT_BW_20ULL         22
  367 #define IEEE80211_RADIOTAP_VHT_BW_20ULU         23
  368 #define IEEE80211_RADIOTAP_VHT_BW_20UUL         24
  369 #define IEEE80211_RADIOTAP_VHT_BW_20UUU         25
  370 
  371 #endif /* !_NET80211_IEEE80211_RADIOTAP_H_ */

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