GNUnet  0.10.x
ieee80211_radiotap.h
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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  */
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  */
201 
202  /* valid in every it_present bitmap, even vendor namespaces */
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 */
257 static inline u16
259 {
260  return p[0] | p[1] << 8;
261 }
262 
263 
264 static inline int
266 {
267  struct ieee80211_radiotap_header *hdr =
268  (struct ieee80211_radiotap_header *)data;
269 
270  return get_unaligned_le16((const u8 *)&hdr->it_len);
271 }
272 
273 #endif /* IEEE80211_RADIOTAP_H */
static struct GNUNET_OS_Process * p
Helper process we started.
Definition: gnunet-qr.c:59
struct ieee80211_radiotap_header __packed
static u16 get_unaligned_le16(const u8 *p)
uint32_t data
The data value.
ieee80211_radiotap_type
static int ieee80211_get_radiotap_len(unsigned char *data)