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wireshark/epan/dissectors/packet-radiotap.c

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/*
* packet-radiotap.c
* Decode packets with a Radiotap header
*
* $Id$
*
* Wireshark - Network traffic analyzer
* By Gerald Combs <gerald@wireshark.org>
* Copyright 1998 Gerald Combs
*
* Copied from README.developer
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include <glib.h>
#include <string.h>
#include <epan/packet.h>
#include <epan/crc32.h>
#include <epan/frequency-utils.h>
#include "packet-ieee80211.h"
#include "packet-radiotap.h"
/* Written with info from:
*
* http://madwifi.org/wiki/DevDocs/RadiotapHeader
* NetBSD's ieee80211_radiotap.h file
*/
struct ieee80211_radiotap_header {
guint8 it_version; /* Version 0. Only increases
* for drastic changes,
* introduction of compatible
* new fields does not count.
*/
guint8 it_pad;
guint16 it_len; /* length of the whole
* header in bytes, including
* it_version, it_pad,
* it_len, and data fields.
*/
#define MAX_PRESENT 1
guint32 it_present[MAX_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.
*/
};
#define RADIOTAP_MIN_HEADER_LEN 8 /* minimum header length */
#define RADIOTAP_VERSION_OFFSET 0 /* offset of version field */
#define RADIOTAP_LENGTH_OFFSET 2 /* offset of length field */
#define RADIOTAP_PRESENT_OFFSET 4 /* offset of "present" field */
/*
* AAAAAAAAAAAAAAAAAAAAAAAAAARGH.
*
* The current NetBSD ieee80211_radiotap.h has IEEE80211_RADIOTAP_RX_FLAGS
* as 14.
*
* The current OpenBSD ieee80211_radiotap.h has IEEE80211_RADIOTAP_FCS as
* 14.
*
* NetBSD and OpenBSD also differ on what comes *after* 14.
*
* They all use the same DLT_ value for "802.11+radiotap".
*
* This is all wonderfully appreciated by those of us who write code to
* read files containing packets with radiotap headers. I will see if
* I can apply a little cluebat-fu here.
*/
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_XCHANNEL = 18,
IEEE80211_RADIOTAP_EXT = 31
};
/* Channel flags. */
#define IEEE80211_CHAN_TURBO 0x00010 /* Turbo channel */
#define IEEE80211_CHAN_CCK 0x00020 /* CCK channel */
#define IEEE80211_CHAN_OFDM 0x00040 /* OFDM channel */
#define IEEE80211_CHAN_2GHZ 0x00080 /* 2 GHz spectrum channel. */
#define IEEE80211_CHAN_5GHZ 0x00100 /* 5 GHz spectrum channel */
#define IEEE80211_CHAN_PASSIVE 0x00200 /* Only passive scan allowed */
#define IEEE80211_CHAN_DYN 0x00400 /* Dynamic CCK-OFDM channel */
#define IEEE80211_CHAN_GFSK 0x00800 /* GFSK channel (FHSS PHY) */
#define IEEE80211_CHAN_GSM 0x01000 /* 900 MHz spectrum channel */
#define IEEE80211_CHAN_STURBO 0x02000 /* 11a static turbo channel only */
#define IEEE80211_CHAN_HALF 0x04000 /* Half rate channel */
#define IEEE80211_CHAN_QUARTER 0x08000 /* Quarter rate channel */
#define IEEE80211_CHAN_HT20 0x10000 /* HT 20 channel */
#define IEEE80211_CHAN_HT40U 0x20000 /* HT 40 channel w/ ext above */
#define IEEE80211_CHAN_HT40D 0x40000 /* HT 40 channel w/ ext below */
/*
* Useful combinations of channel characteristics.
*/
#define IEEE80211_CHAN_FHSS \
(IEEE80211_CHAN_2GHZ | IEEE80211_CHAN_GFSK)
#define IEEE80211_CHAN_A \
(IEEE80211_CHAN_5GHZ | IEEE80211_CHAN_OFDM)
#define IEEE80211_CHAN_B \
(IEEE80211_CHAN_2GHZ | IEEE80211_CHAN_CCK)
#define IEEE80211_CHAN_PUREG \
(IEEE80211_CHAN_2GHZ | IEEE80211_CHAN_OFDM)
#define IEEE80211_CHAN_G \
(IEEE80211_CHAN_2GHZ | IEEE80211_CHAN_DYN)
#define IEEE80211_CHAN_T \
(IEEE80211_CHAN_5GHZ | IEEE80211_CHAN_OFDM | IEEE80211_CHAN_TURBO)
#define IEEE80211_CHAN_108G \
(IEEE80211_CHAN_G | IEEE80211_CHAN_TURBO)
#define IEEE80211_CHAN_108PUREG \
(IEEE80211_CHAN_PUREG | IEEE80211_CHAN_TURBO)
/* 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)
*/
#define IEEE80211_RADIOTAP_F_BADFCS 0x40 /* does not pass FCS check */
#define IEEE80211_RADIOTAP_F_SHORTGI 0x80 /* HT short GI */
/* XXX need max array size */
static const int ieee80211_htrates[16] = {
13, /* IFM_IEEE80211_MCS0 */
26, /* IFM_IEEE80211_MCS1 */
39, /* IFM_IEEE80211_MCS2 */
52, /* IFM_IEEE80211_MCS3 */
78, /* IFM_IEEE80211_MCS4 */
104, /* IFM_IEEE80211_MCS5 */
117, /* IFM_IEEE80211_MCS6 */
130, /* IFM_IEEE80211_MCS7 */
26, /* IFM_IEEE80211_MCS8 */
52, /* IFM_IEEE80211_MCS9 */
78, /* IFM_IEEE80211_MCS10 */
104, /* IFM_IEEE80211_MCS11 */
156, /* IFM_IEEE80211_MCS12 */
208, /* IFM_IEEE80211_MCS13 */
234, /* IFM_IEEE80211_MCS14 */
260, /* IFM_IEEE80211_MCS15 */
};
/* protocol */
static int proto_radiotap = -1;
static int hf_radiotap_version = -1;
static int hf_radiotap_pad = -1;
static int hf_radiotap_length = -1;
static int hf_radiotap_present = -1;
static int hf_radiotap_mactime = -1;
static int hf_radiotap_channel = -1;
static int hf_radiotap_channel_frequency = -1;
static int hf_radiotap_channel_flags = -1;
static int hf_radiotap_channel_flags_turbo = -1;
static int hf_radiotap_channel_flags_cck = -1;
static int hf_radiotap_channel_flags_ofdm = -1;
static int hf_radiotap_channel_flags_2ghz = -1;
static int hf_radiotap_channel_flags_5ghz = -1;
static int hf_radiotap_channel_flags_passive = -1;
static int hf_radiotap_channel_flags_dynamic = -1;
static int hf_radiotap_channel_flags_gfsk = -1;
static int hf_radiotap_channel_flags_gsm = -1;
static int hf_radiotap_channel_flags_sturbo = -1;
static int hf_radiotap_channel_flags_half = -1;
static int hf_radiotap_channel_flags_quarter = -1;
static int hf_radiotap_xchannel = -1;
static int hf_radiotap_xchannel_frequency = -1;
static int hf_radiotap_xchannel_flags = -1;
static int hf_radiotap_xchannel_flags_turbo = -1;
static int hf_radiotap_xchannel_flags_cck = -1;
static int hf_radiotap_xchannel_flags_ofdm = -1;
static int hf_radiotap_xchannel_flags_2ghz = -1;
static int hf_radiotap_xchannel_flags_5ghz = -1;
static int hf_radiotap_xchannel_flags_passive = -1;
static int hf_radiotap_xchannel_flags_dynamic = -1;
static int hf_radiotap_xchannel_flags_gfsk = -1;
static int hf_radiotap_xchannel_flags_gsm = -1;
static int hf_radiotap_xchannel_flags_sturbo = -1;
static int hf_radiotap_xchannel_flags_half = -1;
static int hf_radiotap_xchannel_flags_quarter = -1;
static int hf_radiotap_xchannel_flags_ht20 = -1;
static int hf_radiotap_xchannel_flags_ht40u = -1;
static int hf_radiotap_xchannel_flags_ht40d = -1;
#if 0
static int hf_radiotap_xchannel_maxpower = -1;
#endif
static int hf_radiotap_fhss_hopset = -1;
static int hf_radiotap_fhss_pattern = -1;
static int hf_radiotap_datarate = -1;
static int hf_radiotap_antenna = -1;
static int hf_radiotap_dbm_antsignal = -1;
static int hf_radiotap_db_antsignal = -1;
static int hf_radiotap_dbm_antnoise = -1;
static int hf_radiotap_db_antnoise = -1;
static int hf_radiotap_tx_attenuation = -1;
static int hf_radiotap_db_tx_attenuation = -1;
static int hf_radiotap_txpower = -1;
/* "Present" flags */
static int hf_radiotap_present_tsft = -1;
static int hf_radiotap_present_flags = -1;
static int hf_radiotap_present_rate = -1;
static int hf_radiotap_present_channel = -1;
static int hf_radiotap_present_fhss = -1;
static int hf_radiotap_present_dbm_antsignal = -1;
static int hf_radiotap_present_dbm_antnoise = -1;
static int hf_radiotap_present_lock_quality = -1;
static int hf_radiotap_present_tx_attenuation = -1;
static int hf_radiotap_present_db_tx_attenuation = -1;
static int hf_radiotap_present_dbm_tx_attenuation = -1;
static int hf_radiotap_present_antenna = -1;
static int hf_radiotap_present_db_antsignal = -1;
static int hf_radiotap_present_db_antnoise = -1;
static int hf_radiotap_present_fcs = -1;
static int hf_radiotap_present_xchannel = -1;
static int hf_radiotap_present_ext = -1;
/* "present.flags" flags */
static int hf_radiotap_flags = -1;
static int hf_radiotap_flags_cfp = -1;
static int hf_radiotap_flags_preamble = -1;
static int hf_radiotap_flags_wep = -1;
static int hf_radiotap_flags_frag = -1;
static int hf_radiotap_flags_fcs = -1;
static int hf_radiotap_flags_datapad = -1;
static int hf_radiotap_flags_badfcs = -1;
static int hf_radiotap_flags_shortgi = -1;
static int hf_radiotap_quality = -1;
static int hf_radiotap_fcs = -1;
static int hf_radiotap_fcs_bad = -1;
static gint ett_radiotap = -1;
static gint ett_radiotap_present = -1;
static gint ett_radiotap_flags = -1;
static gint ett_radiotap_channel_flags = -1;
static gint ett_radiotap_xchannel_flags = -1;
static dissector_handle_t ieee80211_handle;
static dissector_handle_t ieee80211_datapad_handle;
static void
dissect_radiotap(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree);
#define BITNO_32(x) (((x) >> 16) ? 16 + BITNO_16((x) >> 16) : BITNO_16((x)))
#define BITNO_16(x) (((x) >> 8) ? 8 + BITNO_8((x) >> 8) : BITNO_8((x)))
#define BITNO_8(x) (((x) >> 4) ? 4 + BITNO_4((x) >> 4) : BITNO_4((x)))
#define BITNO_4(x) (((x) >> 2) ? 2 + BITNO_2((x) >> 2) : BITNO_2((x)))
#define BITNO_2(x) (((x) & 2) ? 1 : 0)
#define BIT(n) (1 << n)
/*
* The NetBSD ieee80211_radiotap man page
* (http://netbsd.gw.com/cgi-bin/man-cgi?ieee80211_radiotap+9+NetBSD-current)
* says:
*
* Radiotap capture fields must be naturally aligned. That is, 16-, 32-,
* and 64-bit fields must begin on 16-, 32-, and 64-bit boundaries, respec-
* tively. In this way, drivers can avoid unaligned accesses to radiotap
* capture fields. radiotap-compliant drivers must insert padding before a
* capture field to ensure its natural alignment. radiotap-compliant packet
* dissectors, such as tcpdump(8), expect the padding.
*/
/*
* Returns the amount required to align "offset" with "width"
*/
#define ALIGN_OFFSET(offset, width) \
( (((offset) + ((width) - 1)) & (~((width) - 1))) - offset )
void
capture_radiotap(const guchar *pd, int offset, int len, packet_counts *ld)
{
guint16 it_len;
guint32 present;
guint8 rflags;
if(!BYTES_ARE_IN_FRAME(offset, len, RADIOTAP_MIN_HEADER_LEN)) {
ld->other ++;
return;
}
it_len = pletohs(&pd[RADIOTAP_LENGTH_OFFSET]);
if(!BYTES_ARE_IN_FRAME(offset, len, it_len)) {
ld->other ++;
return;
}
if(it_len > len) {
/* Header length is bigger than total packet length */
ld->other ++;
return;
}
if(it_len < RADIOTAP_MIN_HEADER_LEN) {
/* Header length is shorter than fixed-length portion of header */
ld->other ++;
return;
}
present = pletohl(&pd[RADIOTAP_PRESENT_OFFSET]);
offset += RADIOTAP_MIN_HEADER_LEN;
it_len -= RADIOTAP_MIN_HEADER_LEN;
rflags = 0;
/*
* IEEE80211_RADIOTAP_TSFT is the lowest-order bit.
*/
if (present & BIT(IEEE80211_RADIOTAP_TSFT)) {
if (it_len < 8) {
/* No room in header for this field. */
ld->other ++;
return;
}
/* That field is present, and it's 8 bits long. */
offset += 8;
it_len -= 8;
}
/*
* IEEE80211_RADIOTAP_FLAGS is the next bit.
*/
if (present & BIT(IEEE80211_RADIOTAP_FLAGS)) {
if (it_len < 1) {
/* No room in header for this field. */
ld->other ++;
return;
}
/* That field is present; fetch it. */
if(!BYTES_ARE_IN_FRAME(offset, len, 1)) {
ld->other ++;
return;
}
rflags = pd[offset];
}
/* 802.11 header follows */
if (rflags & IEEE80211_RADIOTAP_F_DATAPAD)
capture_ieee80211_datapad(pd, offset + it_len, len, ld);
else
capture_ieee80211(pd, offset + it_len, len, ld);
}
void
proto_register_radiotap(void)
{
static const value_string phy_type[] = {
{ 0, "Unknown" },
{ IEEE80211_CHAN_A, "802.11a" },
{ IEEE80211_CHAN_A | IEEE80211_CHAN_HT20, "802.11a (ht20)" },
{ IEEE80211_CHAN_A | IEEE80211_CHAN_HT40U, "802.11a (ht40+)" },
{ IEEE80211_CHAN_A | IEEE80211_CHAN_HT40D, "802.11a (ht40-)" },
{ IEEE80211_CHAN_B, "802.11b" },
{ IEEE80211_CHAN_PUREG, "802.11g (pure-g)" },
{ IEEE80211_CHAN_G, "802.11g" },
{ IEEE80211_CHAN_G | IEEE80211_CHAN_HT20, "802.11g (ht20)" },
{ IEEE80211_CHAN_G | IEEE80211_CHAN_HT40U, "802.11g (ht40+)" },
{ IEEE80211_CHAN_G | IEEE80211_CHAN_HT40D, "802.11g (ht40-)" },
{ IEEE80211_CHAN_T, "802.11a (turbo)" },
{ IEEE80211_CHAN_108PUREG, "802.11g (pure-g, turbo)" },
{ IEEE80211_CHAN_108G, "802.11g (turbo)" },
{ IEEE80211_CHAN_FHSS, "FHSS" },
{ 0, NULL },
};
static const true_false_string preamble_type = {
"Short",
"Long",
};
static hf_register_info hf[] = {
{ &hf_radiotap_version,
{ "Header revision", "radiotap.version",
FT_UINT8, BASE_DEC, NULL, 0x0,
"Version of radiotap header format", HFILL } },
{ &hf_radiotap_pad,
{ "Header pad", "radiotap.pad",
FT_UINT8, BASE_DEC, NULL, 0x0,
"Padding", HFILL } },
{ &hf_radiotap_length,
{ "Header length", "radiotap.length",
FT_UINT16, BASE_DEC, NULL, 0x0,
"Length of header including version, pad, length and data fields", HFILL } },
{ &hf_radiotap_present,
{ "Present flags", "radiotap.present",
FT_UINT32, BASE_HEX, NULL, 0x0, "Bitmask indicating which fields are present", HFILL } },
#define RADIOTAP_MASK_TSFT 0x00000001
#define RADIOTAP_MASK_FLAGS 0x00000002
#define RADIOTAP_MASK_RATE 0x00000004
#define RADIOTAP_MASK_CHANNEL 0x00000008
#define RADIOTAP_MASK_FHSS 0x00000010
#define RADIOTAP_MASK_DBM_ANTSIGNAL 0x00000020
#define RADIOTAP_MASK_DBM_ANTNOISE 0x00000040
#define RADIOTAP_MASK_LOCK_QUALITY 0x00000080
#define RADIOTAP_MASK_TX_ATTENUATION 0x00000100
#define RADIOTAP_MASK_DB_TX_ATTENUATION 0x00000200
#define RADIOTAP_MASK_DBM_TX_ATTENUATION 0x00000400
#define RADIOTAP_MASK_ANTENNA 0x00000800
#define RADIOTAP_MASK_DB_ANTSIGNAL 0x00001000
#define RADIOTAP_MASK_DB_ANTNOISE 0x00002000
#define RADIOTAP_MASK_FCS 0x00004000
#define RADIOTAP_MASK_XCHANNEL 0x00040000
#define RADIOTAP_MASK_EXT 0x80000000
/* Boolean 'present' flags */
{ &hf_radiotap_present_tsft,
{ "TSFT", "radiotap.present.tsft",
FT_BOOLEAN, 32, NULL, RADIOTAP_MASK_TSFT,
"Specifies if the Time Synchronization Function Timer field is present", HFILL } },
{ &hf_radiotap_present_flags,
{ "Flags", "radiotap.present.flags",
FT_BOOLEAN, 32, NULL, RADIOTAP_MASK_FLAGS,
"Specifies if the channel flags field is present", HFILL } },
{ &hf_radiotap_present_rate,
{ "Rate", "radiotap.present.rate",
FT_BOOLEAN, 32, NULL, RADIOTAP_MASK_RATE,
"Specifies if the transmit/receive rate field is present", HFILL } },
{ &hf_radiotap_present_channel,
{ "Channel", "radiotap.present.channel",
FT_BOOLEAN, 32, NULL, RADIOTAP_MASK_CHANNEL,
"Specifies if the transmit/receive frequency field is present", HFILL } },
{ &hf_radiotap_present_fhss,
{ "FHSS", "radiotap.present.fhss",
FT_BOOLEAN, 32, NULL, RADIOTAP_MASK_FHSS,
"Specifies if the hop set and pattern is present for frequency hopping radios", HFILL } },
{ &hf_radiotap_present_dbm_antsignal,
{ "DBM Antenna Signal", "radiotap.present.dbm_antsignal",
FT_BOOLEAN, 32, NULL, RADIOTAP_MASK_DBM_ANTSIGNAL,
"Specifies if the antenna signal strength in dBm is present", HFILL } },
{ &hf_radiotap_present_dbm_antnoise,
{ "DBM Antenna Noise", "radiotap.present.dbm_antnoise",
FT_BOOLEAN, 32, NULL, RADIOTAP_MASK_DBM_ANTNOISE,
"Specifies if the RF noise power at antenna field is present", HFILL } },
{ &hf_radiotap_present_lock_quality,
{ "Lock Quality", "radiotap.present.lock_quality",
FT_BOOLEAN, 32, NULL, RADIOTAP_MASK_LOCK_QUALITY,
"Specifies if the signal quality field is present", HFILL } },
{ &hf_radiotap_present_tx_attenuation,
{ "TX Attenuation", "radiotap.present.tx_attenuation",
FT_BOOLEAN, 32, NULL, RADIOTAP_MASK_TX_ATTENUATION,
"Specifies if the transmit power from max power field is present", HFILL } },
{ &hf_radiotap_present_db_tx_attenuation,
{ "DB TX Attenuation", "radiotap.present.db_tx_attenuation",
FT_BOOLEAN, 32, NULL, RADIOTAP_MASK_DB_TX_ATTENUATION,
"Specifies if the transmit power from max power (in dB) field is present", HFILL } },
{ &hf_radiotap_present_dbm_tx_attenuation,
{ "DBM TX Attenuation", "radiotap.present.dbm_tx_attenuation",
FT_BOOLEAN, 32, NULL, RADIOTAP_MASK_DBM_TX_ATTENUATION,
"Specifies if the transmit power from max power (in dBm) field is present", HFILL } },
{ &hf_radiotap_present_antenna,
{ "Antenna", "radiotap.present.antenna",
FT_BOOLEAN, 32, NULL, RADIOTAP_MASK_ANTENNA,
"Specifies if the antenna number field is present", HFILL } },
{ &hf_radiotap_present_db_antsignal,
{ "DB Antenna Signal", "radiotap.present.db_antsignal",
FT_BOOLEAN, 32, NULL, RADIOTAP_MASK_DB_ANTSIGNAL,
"Specifies if the RF signal power at antenna in dB field is present", HFILL } },
{ &hf_radiotap_present_db_antnoise,
{ "DB Antenna Noise", "radiotap.present.db_antnoise",
FT_BOOLEAN, 32, NULL, RADIOTAP_MASK_DB_ANTNOISE,
"Specifies if the RF signal power at antenna in dBm field is present", HFILL } },
{ &hf_radiotap_present_fcs,
{ "FCS in header", "radiotap.present.fcs",
FT_BOOLEAN, 32, NULL, RADIOTAP_MASK_FCS,
"Specifies if the FCS field is present", HFILL } },
{ &hf_radiotap_present_xchannel,
{ "Channel+", "radiotap.present.xchannel",
FT_BOOLEAN, 32, NULL, RADIOTAP_MASK_XCHANNEL,
"Specifies if the extended channel info field is present", HFILL } },
{ &hf_radiotap_present_ext,
{ "Ext", "radiotap.present.ext",
FT_BOOLEAN, 32, NULL, RADIOTAP_MASK_EXT,
"Specifies if there are any extensions to the header present", HFILL } },
/* Boolean 'present.flags' flags */
{ &hf_radiotap_flags,
{ "Flags", "radiotap.flags",
FT_UINT8, BASE_HEX, NULL, 0x0, "", HFILL } },
{ &hf_radiotap_flags_cfp,
{ "CFP", "radiotap.flags.cfp",
FT_BOOLEAN, 8, NULL, IEEE80211_RADIOTAP_F_CFP,
"Sent/Received during CFP", HFILL } },
{ &hf_radiotap_flags_preamble,
{ "Preamble", "radiotap.flags.preamble",
FT_BOOLEAN, 8, TFS(&preamble_type), IEEE80211_RADIOTAP_F_SHORTPRE,
"Sent/Received with short preamble", HFILL } },
{ &hf_radiotap_flags_wep,
{ "WEP", "radiotap.flags.wep",
FT_BOOLEAN, 8, NULL, IEEE80211_RADIOTAP_F_WEP,
"Sent/Received with WEP encryption", HFILL } },
{ &hf_radiotap_flags_frag,
{ "Fragmentation", "radiotap.flags.frag",
FT_BOOLEAN, 8, NULL, IEEE80211_RADIOTAP_F_FRAG,
"Sent/Received with fragmentation", HFILL } },
{ &hf_radiotap_flags_fcs,
{ "FCS at end", "radiotap.flags.fcs",
FT_BOOLEAN, 8, NULL, IEEE80211_RADIOTAP_F_FCS,
"Frame includes FCS at end", HFILL } },
{ &hf_radiotap_flags_datapad,
{ "Data Pad", "radiotap.flags.datapad",
FT_BOOLEAN, 8, NULL, IEEE80211_RADIOTAP_F_DATAPAD,
"Frame has padding between 802.11 header and payload", HFILL } },
{ &hf_radiotap_flags_badfcs,
{ "Bad FCS", "radiotap.flags.badfcs",
FT_BOOLEAN, 8, NULL, IEEE80211_RADIOTAP_F_BADFCS,
"Frame received with bad FCS", HFILL } },
{ &hf_radiotap_flags_shortgi,
{ "Short GI", "radiotap.flags.shortgi",
FT_BOOLEAN, 8, NULL, IEEE80211_RADIOTAP_F_SHORTGI,
"Frame Sent/Received with HT short Guard Interval", HFILL } },
{ &hf_radiotap_mactime,
{ "MAC timestamp", "radiotap.mactime",
FT_UINT64, BASE_DEC, NULL, 0x0,
" Value in microseconds of the MAC's Time Synchronization Function timer when the first bit of the MPDU arrived at the MAC.", HFILL } },
{ &hf_radiotap_quality,
{ "Signal Quality", "radiotap.quality",
FT_UINT16, BASE_DEC, NULL, 0x0,
"Signal quality (unitless measure)", HFILL } },
{ &hf_radiotap_fcs,
{ "802.11 FCS", "radiotap.fcs",
FT_UINT32, BASE_HEX, NULL, 0x0,
"Frame check sequence of this frame", HFILL } },
{ &hf_radiotap_channel,
{ "Channel", "radiotap.channel",
FT_UINT32, BASE_DEC, NULL, 0x0,
"802.11 channel number that this frame was sent/received on", HFILL } },
{ &hf_radiotap_channel_frequency,
{ "Channel frequency", "radiotap.channel.freq",
FT_UINT32, BASE_DEC, NULL, 0x0,
"Channel frequency in megahertz that this frame was sent/received on", HFILL } },
{ &hf_radiotap_channel_flags,
{ "Channel type", "radiotap.channel.type",
FT_UINT16, BASE_HEX, VALS(phy_type), 0x0,
"Channel type", HFILL } },
{ &hf_radiotap_channel_flags_turbo,
{ "Turbo", "radiotap.channel.type.turbo",
FT_BOOLEAN, 16, NULL, 0x0010, "Channel Type Turbo", HFILL } },
{ &hf_radiotap_channel_flags_cck,
{ "Complementary Code Keying (CCK)", "radiotap.channel.type.cck",
FT_BOOLEAN, 16, NULL, 0x0020, "Channel Type Complementary Code Keying (CCK) Modulation", HFILL } },
{ &hf_radiotap_channel_flags_ofdm,
{ "Orthogonal Frequency-Division Multiplexing (OFDM)", "radiotap.channel.type.ofdm",
FT_BOOLEAN, 16, NULL, 0x0040, "Channel Type Orthogonal Frequency-Division Multiplexing (OFDM)", HFILL } },
{ &hf_radiotap_channel_flags_2ghz,
{ "2 GHz spectrum", "radiotap.channel.type.2ghz",
FT_BOOLEAN, 16, NULL, 0x0080, "Channel Type 2 GHz spectrum", HFILL } },
{ &hf_radiotap_channel_flags_5ghz,
{ "5 GHz spectrum", "radiotap.channel.type.5ghz",
FT_BOOLEAN, 16, NULL, 0x0100, "Channel Type 5 GHz spectrum", HFILL } },
{ &hf_radiotap_channel_flags_passive,
{ "Passive", "radiotap.channel.type.passive",
FT_BOOLEAN, 16, NULL, 0x0200, "Channel Type Passive", HFILL } },
{ &hf_radiotap_channel_flags_dynamic,
{ "Dynamic CCK-OFDM", "radiotap.channel.type.dynamic",
FT_BOOLEAN, 16, NULL, 0x0400, "Channel Type Dynamic CCK-OFDM Channel", HFILL } },
{ &hf_radiotap_channel_flags_gfsk,
{ "Gaussian Frequency Shift Keying (GFSK)", "radiotap.channel.type.gfsk",
FT_BOOLEAN, 16, NULL, 0x0800, "Channel Type Gaussian Frequency Shift Keying (GFSK) Modulation", HFILL } },
{ &hf_radiotap_channel_flags_gsm,
{ "GSM (900MHz)", "radiotap.channel.type.gsm",
FT_BOOLEAN, 16, NULL, 0x1000, "Channel Type GSM", HFILL } },
{ &hf_radiotap_channel_flags_sturbo,
{ "Static Turbo", "radiotap.channel.type.sturbo",
FT_BOOLEAN, 16, NULL, 0x2000, "Channel Type Status Turbo", HFILL } },
{ &hf_radiotap_channel_flags_half,
{ "Half Rate Channel (10MHz Channel Width)", "radiotap.channel.type.half",
FT_BOOLEAN, 16, NULL, 0x4000, "Channel Type Half Rate", HFILL } },
{ &hf_radiotap_channel_flags_quarter,
{ "Quarter Rate Channel (5MHz Channel Width)", "radiotap.channel.type.quarter",
FT_BOOLEAN, 16, NULL, 0x8000, "Channel Type Quarter Rate", HFILL } },
{ &hf_radiotap_xchannel,
{ "Channel number", "radiotap.xchannel",
FT_UINT32, BASE_DEC, NULL, 0x0, "", HFILL } },
{ &hf_radiotap_xchannel_frequency,
{ "Channel frequency", "radiotap.xchannel.freq",
FT_UINT32, BASE_DEC, NULL, 0x0, "", HFILL } },
{ &hf_radiotap_xchannel_flags,
{ "Channel type", "radiotap.xchannel.flags",
FT_UINT32, BASE_HEX, VALS(phy_type), 0x0, "", HFILL } },
{ &hf_radiotap_xchannel_flags_turbo,
{ "Turbo", "radiotap.xchannel.type.turbo",
FT_BOOLEAN, 24, NULL, 0x0010, "Channel Type Turbo", HFILL } },
{ &hf_radiotap_xchannel_flags_cck,
{ "Complementary Code Keying (CCK)", "radiotap.xchannel.type.cck",
FT_BOOLEAN, 24, NULL, 0x0020, "Channel Type Complementary Code Keying (CCK) Modulation", HFILL } },
{ &hf_radiotap_xchannel_flags_ofdm,
{ "Orthogonal Frequency-Division Multiplexing (OFDM)", "radiotap.xchannel.type.ofdm",
FT_BOOLEAN, 24, NULL, 0x0040, "Channel Type Orthogonal Frequency-Division Multiplexing (OFDM)", HFILL } },
{ &hf_radiotap_xchannel_flags_2ghz,
{ "2 GHz spectrum", "radiotap.xchannel.type.2ghz",
FT_BOOLEAN, 24, NULL, 0x0080, "Channel Type 2 GHz spectrum", HFILL } },
{ &hf_radiotap_xchannel_flags_5ghz,
{ "5 GHz spectrum", "radiotap.xchannel.type.5ghz",
FT_BOOLEAN, 24, NULL, 0x0100, "Channel Type 5 GHz spectrum", HFILL } },
{ &hf_radiotap_xchannel_flags_passive,
{ "Passive", "radiotap.channel.xtype.passive",
FT_BOOLEAN, 24, NULL, 0x0200, "Channel Type Passive", HFILL } },
{ &hf_radiotap_xchannel_flags_dynamic,
{ "Dynamic CCK-OFDM", "radiotap.xchannel.type.dynamic",
FT_BOOLEAN, 24, NULL, 0x0400, "Channel Type Dynamic CCK-OFDM Channel", HFILL } },
{ &hf_radiotap_xchannel_flags_gfsk,
{ "Gaussian Frequency Shift Keying (GFSK)", "radiotap.xchannel.type.gfsk",
FT_BOOLEAN, 24, NULL, 0x0800, "Channel Type Gaussian Frequency Shift Keying (GFSK) Modulation", HFILL } },
{ &hf_radiotap_xchannel_flags_gsm,
{ "GSM (900MHz)", "radiotap.xchannel.type.gsm",
FT_BOOLEAN, 24, NULL, 0x1000, "Channel Type GSM", HFILL } },
{ &hf_radiotap_xchannel_flags_sturbo,
{ "Static Turbo", "radiotap.xchannel.type.sturbo",
FT_BOOLEAN, 24, NULL, 0x2000, "Channel Type Status Turbo", HFILL } },
{ &hf_radiotap_xchannel_flags_half,
{ "Half Rate Channel (10MHz Channel Width)", "radiotap.xchannel.type.half",
FT_BOOLEAN, 24, NULL, 0x4000, "Channel Type Half Rate", HFILL } },
{ &hf_radiotap_xchannel_flags_quarter,
{ "Quarter Rate Channel (5MHz Channel Width)", "radiotap.xchannel.type.quarter",
FT_BOOLEAN, 24, NULL, 0x8000, "Channel Type Quarter Rate", HFILL } },
{ &hf_radiotap_xchannel_flags_ht20,
{ "HT Channel (20MHz Channel Width)", "radiotap.xchannel.type.ht20",
FT_BOOLEAN, 24, NULL, 0x10000, "Channel Type HT/20", HFILL } },
{ &hf_radiotap_xchannel_flags_ht40u,
{ "HT Channel (40MHz Channel Width with Extension channel above)", "radiotap.xchannel.type.ht40u",
FT_BOOLEAN, 24, NULL, 0x20000, "Channel Type HT/40+", HFILL } },
{ &hf_radiotap_xchannel_flags_ht40d,
{ "HT Channel (40MHz Channel Width with Extension channel below)", "radiotap.xchannel.type.ht40d",
FT_BOOLEAN, 24, NULL, 0x40000, "Channel Type HT/40-", HFILL } },
#if 0
{ &hf_radiotap_xchannel_maxpower,
{ "Max transmit power", "radiotap.xchannel.maxpower",
FT_UINT32, BASE_DEC, NULL, 0x0, "", HFILL } },
#endif
{ &hf_radiotap_fhss_hopset,
{ "FHSS Hop Set", "radiotap.fhss.hopset",
FT_UINT8, BASE_DEC, NULL, 0x0,
"Frequency Hopping Spread Spectrum hopset", HFILL } },
{ &hf_radiotap_fhss_pattern,
{ "FHSS Pattern", "radiotap.fhss.pattern",
FT_UINT8, BASE_DEC, NULL, 0x0,
"Frequency Hopping Spread Spectrum hop pattern", HFILL } },
{ &hf_radiotap_datarate,
{ "Data rate", "radiotap.datarate",
FT_UINT32, BASE_DEC, NULL, 0x0,
"Speed this frame was sent/received at", HFILL } },
{ &hf_radiotap_antenna,
{ "Antenna", "radiotap.antenna",
FT_UINT32, BASE_DEC, NULL, 0x0,
"Antenna number this frame was sent/received over (starting at 0)", HFILL } },
{ &hf_radiotap_dbm_antsignal,
{ "SSI Signal (dBm)", "radiotap.dbm_antsignal",
FT_INT32, BASE_DEC, NULL, 0x0,
"RF signal power at the antenna from a fixed, arbitrary value in decibels from one milliwatt", HFILL } },
{ &hf_radiotap_db_antsignal,
{ "SSI Signal (dB)", "radiotap.db_antsignal",
FT_UINT32, BASE_DEC, NULL, 0x0,
"RF signal power at the antenna from a fixed, arbitrary value in decibels", HFILL } },
{ &hf_radiotap_dbm_antnoise,
{ "SSI Noise (dBm)", "radiotap.dbm_antnoise",
FT_INT32, BASE_DEC, NULL, 0x0,
"RF noise power at the antenna from a fixed, arbitrary value in decibels per one milliwatt", HFILL } },
{ &hf_radiotap_db_antnoise,
{ "SSI Noise (dB)", "radiotap.db_antnoise",
FT_UINT32, BASE_DEC, NULL, 0x0,
"RF noise power at the antenna from a fixed, arbitrary value in decibels", HFILL } },
{ &hf_radiotap_tx_attenuation,
{ "Transmit attenuation", "radiotap.txattenuation",
FT_UINT16, BASE_DEC, NULL, 0x0,
"Transmit power expressed as unitless distance from max power set at factory (0 is max power)", HFILL } },
{ &hf_radiotap_db_tx_attenuation,
{ "Transmit attenuation (dB)", "radiotap.db_txattenuation",
FT_UINT16, BASE_DEC, NULL, 0x0,
"Transmit power expressed as decibels from max power set at factory (0 is max power)", HFILL } },
{ &hf_radiotap_txpower,
{ "Transmit power", "radiotap.txpower",
FT_INT32, BASE_DEC, NULL, 0x0,
"Transmit power in decibels per one milliwatt (dBm)", HFILL } },
/* Special variables */
{ &hf_radiotap_fcs_bad,
{ "Bad FCS", "radiotap.fcs_bad",
FT_BOOLEAN, BASE_NONE, NULL, 0x0,
"Specifies if this frame has a bad frame check sequence", HFILL } },
};
static gint *ett[] = {
&ett_radiotap,
&ett_radiotap_present,
&ett_radiotap_flags,
&ett_radiotap_channel_flags,
&ett_radiotap_xchannel_flags
};
proto_radiotap = proto_register_protocol("IEEE 802.11 Radiotap Capture header", "802.11 Radiotap", "radiotap");
proto_register_field_array(proto_radiotap, hf, array_length(hf));
proto_register_subtree_array(ett, array_length(ett));
register_dissector("radiotap", dissect_radiotap, proto_radiotap);
}
static void
dissect_radiotap(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
proto_tree *radiotap_tree = NULL;
proto_tree *pt, *present_tree = NULL;
proto_tree *ft, *flags_tree = NULL;
proto_item *ti = NULL, *hidden_item;
proto_item *hdr_fcs_ti = NULL;
int hdr_fcs_offset = 0;
int align_offset, offset;
guint32 sent_fcs = 0;
guint32 calc_fcs;
tvbuff_t *next_tvb;
guint32 version;
guint length, length_remaining;
guint32 rate, freq, flags;
gint8 dbm;
guint8 db, rflags;
guint32 present, next_present;
int bit;
if(check_col(pinfo->cinfo, COL_PROTOCOL))
col_set_str(pinfo->cinfo, COL_PROTOCOL, "WLAN");
if(check_col(pinfo->cinfo, COL_INFO))
col_clear(pinfo->cinfo, COL_INFO);
offset = 0;
version = tvb_get_guint8(tvb, offset);
length = tvb_get_letohs(tvb, offset+2);
present = tvb_get_letohl(tvb, offset+4);
if(check_col(pinfo->cinfo, COL_INFO))
col_add_fstr(pinfo->cinfo, COL_INFO, "Radiotap Capture v%u, Length %u",
version, length);
/* Dissect the packet */
if (tree) {
ti = proto_tree_add_protocol_format(tree, proto_radiotap,
tvb, 0, length, "Radiotap Header v%u, Length %u", version, length);
radiotap_tree = proto_item_add_subtree(ti, ett_radiotap);
proto_tree_add_uint(radiotap_tree, hf_radiotap_version,
tvb, offset, 1, version);
proto_tree_add_item(radiotap_tree, hf_radiotap_pad,
tvb, offset + 1, 1, FALSE);
ti = proto_tree_add_uint(radiotap_tree, hf_radiotap_length,
tvb, offset + 2, 2, length);
}
length_remaining = length;
/*
* FIXME: This only works if there is exactly 1 it_present
* field in the header
*/
if (length_remaining < RADIOTAP_MIN_HEADER_LEN) {
/*
* Radiotap header is shorter than the fixed-length portion
* plus one "present" bitset.
*/
if (tree)
proto_item_append_text(ti, " (bogus - minimum length is 8)");
return;
}
/* Subtree for the "present flags" bitfield. */
if (tree) {
pt = proto_tree_add_uint(radiotap_tree, hf_radiotap_present,
tvb, offset + 4, 4, present);
present_tree = proto_item_add_subtree(pt, ett_radiotap_present);
proto_tree_add_item(present_tree, hf_radiotap_present_tsft,
tvb, 4, 4, TRUE);
proto_tree_add_item(present_tree, hf_radiotap_present_flags,
tvb, 4, 4, TRUE);
proto_tree_add_item(present_tree, hf_radiotap_present_rate,
tvb, 4, 4, TRUE);
proto_tree_add_item(present_tree, hf_radiotap_present_channel,
tvb, 4, 4, TRUE);
proto_tree_add_item(present_tree, hf_radiotap_present_fhss,
tvb, 4, 4, TRUE);
proto_tree_add_item(present_tree, hf_radiotap_present_dbm_antsignal,
tvb, 4, 4, TRUE);
proto_tree_add_item(present_tree, hf_radiotap_present_dbm_antnoise,
tvb, 4, 4, TRUE);
proto_tree_add_item(present_tree, hf_radiotap_present_lock_quality,
tvb, 4, 4, TRUE);
proto_tree_add_item(present_tree, hf_radiotap_present_tx_attenuation,
tvb, 4, 4, TRUE);
proto_tree_add_item(present_tree, hf_radiotap_present_db_tx_attenuation,
tvb, 4, 4, TRUE);
proto_tree_add_item(present_tree, hf_radiotap_present_dbm_tx_attenuation,
tvb, 4, 4, TRUE);
proto_tree_add_item(present_tree, hf_radiotap_present_antenna,
tvb, 4, 4, TRUE);
proto_tree_add_item(present_tree, hf_radiotap_present_db_antsignal,
tvb, 4, 4, TRUE);
proto_tree_add_item(present_tree, hf_radiotap_present_db_antnoise,
tvb, 4, 4, TRUE);
proto_tree_add_item(present_tree, hf_radiotap_present_fcs,
tvb, 4, 4, TRUE);
proto_tree_add_item(present_tree, hf_radiotap_present_xchannel,
tvb, 4, 4, TRUE);
proto_tree_add_item(present_tree, hf_radiotap_present_ext,
tvb, 4, 4, TRUE);
}
offset += RADIOTAP_MIN_HEADER_LEN;
length_remaining -= RADIOTAP_MIN_HEADER_LEN;
rflags = 0;
for (; present; present = next_present) {
/* clear the least significant bit that is set */
next_present = present & (present - 1);
/* extract the least significant bit that is set */
bit = BITNO_32(present ^ next_present);
switch (bit) {
case IEEE80211_RADIOTAP_FLAGS:
if (length_remaining < 1)
break;
rflags = tvb_get_guint8(tvb, offset);
if (tree) {
ft = proto_tree_add_item(radiotap_tree, hf_radiotap_flags,
tvb, offset, 1, FALSE);
flags_tree = proto_item_add_subtree(ft, ett_radiotap_flags);
proto_tree_add_item(flags_tree, hf_radiotap_flags_cfp,
tvb, offset, 1, FALSE);
proto_tree_add_item(flags_tree, hf_radiotap_flags_preamble,
tvb, offset, 1, FALSE);
proto_tree_add_item(flags_tree, hf_radiotap_flags_wep,
tvb, offset, 1, FALSE);
proto_tree_add_item(flags_tree, hf_radiotap_flags_frag,
tvb, offset, 1, FALSE);
proto_tree_add_item(flags_tree, hf_radiotap_flags_fcs,
tvb, offset, 1, FALSE);
proto_tree_add_item(flags_tree, hf_radiotap_flags_datapad,
tvb, offset, 1, FALSE);
proto_tree_add_item(flags_tree, hf_radiotap_flags_badfcs,
tvb, offset, 1, FALSE);
proto_tree_add_item(flags_tree, hf_radiotap_flags_shortgi,
tvb, offset, 1, FALSE);
}
offset++;
length_remaining--;
break;
case IEEE80211_RADIOTAP_RATE:
if (length_remaining < 1)
break;
rate = tvb_get_guint8(tvb, offset);
if (rate & 0x80) {
/* XXX adjust by CW and short GI like other sniffers? */
rate = ieee80211_htrates[rate & 0xf];
}
if (check_col(pinfo->cinfo, COL_TX_RATE)) {
col_add_fstr(pinfo->cinfo, COL_TX_RATE, "%d.%d",
rate / 2, rate & 1 ? 5 : 0);
}
if (tree) {
proto_tree_add_uint_format(radiotap_tree, hf_radiotap_datarate,
tvb, offset, 1, tvb_get_guint8(tvb, offset),
"Data Rate: %d.%d Mb/s", rate / 2, rate & 1 ? 5 : 0);
}
offset++;
length_remaining--;
break;
case IEEE80211_RADIOTAP_DBM_ANTSIGNAL:
if (length_remaining < 1)
break;
dbm = (gint8) tvb_get_guint8(tvb, offset);
if (check_col(pinfo->cinfo, COL_RSSI)) {
col_add_fstr(pinfo->cinfo, COL_RSSI, "%d dBm", dbm);
}
if (tree) {
proto_tree_add_int_format(radiotap_tree,
hf_radiotap_dbm_antsignal,
tvb, offset, 1, dbm,
"SSI Signal: %d dBm", dbm);
}
offset++;
length_remaining--;
break;
case IEEE80211_RADIOTAP_DB_ANTSIGNAL:
if (length_remaining < 1)
break;
db = tvb_get_guint8(tvb, offset);
if (check_col(pinfo->cinfo, COL_RSSI)) {
col_add_fstr(pinfo->cinfo, COL_RSSI, "%u dB", db);
}
if (tree) {
proto_tree_add_uint_format(radiotap_tree,
hf_radiotap_db_antsignal,
tvb, offset, 1, db,
"SSI Signal: %u dB", db);
}
offset++;
length_remaining--;
break;
case IEEE80211_RADIOTAP_DBM_ANTNOISE:
if (length_remaining < 1)
break;
dbm = (gint8) tvb_get_guint8(tvb, offset);
if (tree) {
proto_tree_add_int_format(radiotap_tree,
hf_radiotap_dbm_antnoise,
tvb, offset, 1, dbm,
"SSI Noise: %d dBm", dbm);
}
offset++;
length_remaining--;
break;
case IEEE80211_RADIOTAP_DB_ANTNOISE:
if (length_remaining < 1)
break;
db = tvb_get_guint8(tvb, offset);
if (tree) {
proto_tree_add_uint_format(radiotap_tree,
hf_radiotap_db_antnoise,
tvb, offset, 1, db,
"SSI Noise: %u dB", db);
}
offset++;
length_remaining--;
break;
case IEEE80211_RADIOTAP_ANTENNA:
if (length_remaining < 1)
break;
if (tree) {
proto_tree_add_uint(radiotap_tree, hf_radiotap_antenna,
tvb, offset, 1, tvb_get_guint8(tvb, offset));
}
offset++;
length_remaining--;
break;
case IEEE80211_RADIOTAP_DBM_TX_POWER:
if (length_remaining < 1)
break;
if (tree) {
proto_tree_add_int(radiotap_tree, hf_radiotap_txpower,
tvb, offset, 1, tvb_get_guint8(tvb, offset));
}
offset++;
length_remaining--;
break;
case IEEE80211_RADIOTAP_CHANNEL:
{
proto_item *it;
proto_tree *flags_tree;
gchar *chan_str;
align_offset = ALIGN_OFFSET(offset, 2);
offset += align_offset;
length_remaining -= align_offset;
if (length_remaining < 2)
break;
if (tree) {
freq = tvb_get_letohs(tvb, offset);
flags = tvb_get_letohs(tvb, offset+2);
chan_str = ieee80211_mhz_to_str(freq);
if (check_col(pinfo->cinfo, COL_FREQ_CHAN)) {
col_add_fstr(pinfo->cinfo, COL_FREQ_CHAN, "%s", chan_str);
}
proto_tree_add_uint_format(radiotap_tree, hf_radiotap_channel_frequency,
tvb, offset, 2, freq,
"Channel frequency: %s", chan_str);
g_free(chan_str);
/* We're already 2-byte aligned. */
it = proto_tree_add_uint(radiotap_tree, hf_radiotap_channel_flags,
tvb, offset+2, 2, flags);
flags_tree = proto_item_add_subtree(it, ett_radiotap_channel_flags);
proto_tree_add_boolean(flags_tree, hf_radiotap_channel_flags_turbo,
tvb, offset+2, 1, flags);
proto_tree_add_boolean(flags_tree, hf_radiotap_channel_flags_cck,
tvb, offset+2, 1, flags);
proto_tree_add_boolean(flags_tree, hf_radiotap_channel_flags_ofdm,
tvb, offset+2, 1, flags);
proto_tree_add_boolean(flags_tree, hf_radiotap_channel_flags_2ghz,
tvb, offset+2, 1, flags);
proto_tree_add_boolean(flags_tree, hf_radiotap_channel_flags_5ghz,
tvb, offset+3, 1, flags);
proto_tree_add_boolean(flags_tree, hf_radiotap_channel_flags_passive,
tvb, offset+3, 1, flags);
proto_tree_add_boolean(flags_tree, hf_radiotap_channel_flags_dynamic,
tvb, offset+3, 1, flags);
proto_tree_add_boolean(flags_tree, hf_radiotap_channel_flags_gfsk,
tvb, offset+3, 1, flags);
proto_tree_add_boolean(flags_tree, hf_radiotap_channel_flags_gsm,
tvb, offset+3, 1, flags);
proto_tree_add_boolean(flags_tree, hf_radiotap_channel_flags_sturbo,
tvb, offset+3, 1, flags);
proto_tree_add_boolean(flags_tree, hf_radiotap_channel_flags_half,
tvb, offset+3, 1, flags);
proto_tree_add_boolean(flags_tree, hf_radiotap_channel_flags_quarter,
tvb, offset+3, 1, flags);
}
offset+=4 /* Channel + flags */;
length_remaining-=4;
break;
}
case IEEE80211_RADIOTAP_XCHANNEL: {
proto_item *it;
proto_tree *flags_tree;
align_offset = ALIGN_OFFSET(offset, 4);
offset += align_offset;
length_remaining -= align_offset;
if (length_remaining < 8)
break;
if (tree) {
int channel;
guint8 maxpower;
flags = tvb_get_letohl(tvb, offset);
freq = tvb_get_letohs(tvb, offset+4);
channel = tvb_get_guint8(tvb, offset+6);
maxpower = tvb_get_guint8(tvb, offset+7);
proto_tree_add_uint(radiotap_tree, hf_radiotap_xchannel,
tvb, offset+6, 1, (guint32) channel);
proto_tree_add_uint(radiotap_tree, hf_radiotap_xchannel_frequency,
tvb, offset+4, 2, freq);
it = proto_tree_add_uint(radiotap_tree, hf_radiotap_xchannel_flags,
tvb, offset+0, 4, flags);
flags_tree = proto_item_add_subtree(it, ett_radiotap_xchannel_flags);
proto_tree_add_boolean(flags_tree, hf_radiotap_xchannel_flags_turbo,
tvb, offset+0, 1, flags);
proto_tree_add_boolean(flags_tree, hf_radiotap_xchannel_flags_cck,
tvb, offset+0, 1, flags);
proto_tree_add_boolean(flags_tree, hf_radiotap_xchannel_flags_ofdm,
tvb, offset+0, 1, flags);
proto_tree_add_boolean(flags_tree, hf_radiotap_xchannel_flags_2ghz,
tvb, offset+0, 1, flags);
proto_tree_add_boolean(flags_tree, hf_radiotap_xchannel_flags_5ghz,
tvb, offset+1, 1, flags);
proto_tree_add_boolean(flags_tree, hf_radiotap_xchannel_flags_passive,
tvb, offset+1, 1, flags);
proto_tree_add_boolean(flags_tree, hf_radiotap_xchannel_flags_dynamic,
tvb, offset+1, 1, flags);
proto_tree_add_boolean(flags_tree, hf_radiotap_xchannel_flags_gfsk,
tvb, offset+1, 1, flags);
proto_tree_add_boolean(flags_tree, hf_radiotap_xchannel_flags_gsm,
tvb, offset+1, 1, flags);
proto_tree_add_boolean(flags_tree, hf_radiotap_xchannel_flags_sturbo,
tvb, offset+1, 1, flags);
proto_tree_add_boolean(flags_tree, hf_radiotap_xchannel_flags_half,
tvb, offset+1, 1, flags);
proto_tree_add_boolean(flags_tree, hf_radiotap_xchannel_flags_quarter,
tvb, offset+1, 1, flags);
proto_tree_add_boolean(flags_tree, hf_radiotap_xchannel_flags_ht20,
tvb, offset+2, 1, flags);
proto_tree_add_boolean(flags_tree, hf_radiotap_xchannel_flags_ht40u,
tvb, offset+2, 1, flags);
proto_tree_add_boolean(flags_tree, hf_radiotap_xchannel_flags_ht40d,
tvb, offset+2, 1, flags);
#if 0
proto_tree_add_uint(radiotap_tree, hf_radiotap_xchannel_maxpower,
tvb, offset+7, 1, maxpower);
#endif
}
offset+=8 /* flags + freq + ieee + maxregpower */;
length_remaining-=8;
break;
}
case IEEE80211_RADIOTAP_FHSS:
align_offset = ALIGN_OFFSET(offset, 2);
offset += align_offset;
length_remaining -= align_offset;
if (length_remaining < 2)
break;
proto_tree_add_item(radiotap_tree, hf_radiotap_fhss_hopset,
tvb, offset, 1, FALSE);
proto_tree_add_item(radiotap_tree, hf_radiotap_fhss_pattern,
tvb, offset, 1, FALSE);
offset+=2;
length_remaining-=2;
break;
case IEEE80211_RADIOTAP_TX_ATTENUATION:
align_offset = ALIGN_OFFSET(offset, 2);
offset += align_offset;
length_remaining -= align_offset;
if (length_remaining < 2)
break;
proto_tree_add_item(radiotap_tree, hf_radiotap_tx_attenuation,
tvb, offset, 2, FALSE);
offset+=2;
length_remaining-=2;
break;
case IEEE80211_RADIOTAP_DB_TX_ATTENUATION:
align_offset = ALIGN_OFFSET(offset, 2);
offset += align_offset;
length_remaining -= align_offset;
if (length_remaining < 2)
break;
proto_tree_add_item(radiotap_tree, hf_radiotap_db_tx_attenuation,
tvb, offset, 2, FALSE);
offset+=2;
length_remaining-=2;
break;
case IEEE80211_RADIOTAP_TSFT:
align_offset = ALIGN_OFFSET(offset, 8);
offset += align_offset;
length_remaining -= align_offset;
if (length_remaining < 8)
break;
if (tree) {
proto_tree_add_uint64(radiotap_tree, hf_radiotap_mactime,
tvb, offset, 8, tvb_get_letoh64(tvb, offset));
}
offset+=8;
length_remaining-=8;
break;
case IEEE80211_RADIOTAP_LOCK_QUALITY:
align_offset = ALIGN_OFFSET(offset, 2);
offset += align_offset;
length_remaining -= align_offset;
if (length_remaining < 2)
break;
if (tree) {
proto_tree_add_uint(radiotap_tree, hf_radiotap_quality,
tvb, offset, 2, tvb_get_letohs(tvb, offset));
}
offset+=2;
length_remaining-=2;
break;
case IEEE80211_RADIOTAP_FCS:
/* This handles the case of an FCS existing inside the radiotap header. */
align_offset = ALIGN_OFFSET(offset, 4);
offset += align_offset;
length_remaining -= align_offset;
if (length_remaining < 4)
break;
if (tree) {
sent_fcs = tvb_get_ntohl(tvb, offset);
hdr_fcs_ti = proto_tree_add_uint(radiotap_tree, hf_radiotap_fcs,
tvb, offset, 4, sent_fcs);
hdr_fcs_offset = offset;
}
offset+=4;
length_remaining-=4;
break;
default:
/*
* This indicates a field whose size we do not
* know, so we cannot proceed.
*/
next_present = 0;
continue;
}
}
/* This handles the case of an FCS exiting at the end of the frame. */
if (rflags & IEEE80211_RADIOTAP_F_FCS)
pinfo->pseudo_header->ieee_802_11.fcs_len = 4;
else
pinfo->pseudo_header->ieee_802_11.fcs_len = 0;
/* Grab the rest of the frame. */
next_tvb = tvb_new_subset(tvb, length, -1, -1);
/* If we had an in-header FCS, check it. */
if (hdr_fcs_ti) {
/* It would be very strange for the header to have an FCS for the
* frame *and* the frame to have the FCS at the end, but it's possible, so
* take that into account by using the FCS length recorded in pinfo. */
/* Watch out for [erroneously] short frames */
if (tvb_length(next_tvb) > (unsigned int) pinfo->pseudo_header->ieee_802_11.fcs_len) {
calc_fcs = crc32_802_tvb(next_tvb,
tvb_length(next_tvb) - pinfo->pseudo_header->ieee_802_11.fcs_len);
/* By virtue of hdr_fcs_ti being set, we know that 'tree' is set,
* so there's no need to check it here. */
if (calc_fcs == sent_fcs) {
proto_item_append_text(hdr_fcs_ti, " [correct]");
}
else {
proto_item_append_text(hdr_fcs_ti,
" [incorrect, should be 0x%08x]", calc_fcs);
hidden_item = proto_tree_add_boolean(radiotap_tree, hf_radiotap_fcs_bad,
tvb, hdr_fcs_offset, 4, TRUE);
PROTO_ITEM_SET_HIDDEN(hidden_item);
}
}
else {
proto_item_append_text(hdr_fcs_ti,
" [cannot verify - not enough data]");
}
}
/* dissect the 802.11 header next */
call_dissector((rflags & IEEE80211_RADIOTAP_F_DATAPAD) ?
ieee80211_datapad_handle : ieee80211_handle,
next_tvb, pinfo, tree);
}
void
proto_reg_handoff_radiotap(void)
{
dissector_handle_t radiotap_handle;
/* handle for 802.11 dissector */
ieee80211_handle = find_dissector("wlan");
ieee80211_datapad_handle = find_dissector("wlan_datapad");
radiotap_handle = find_dissector("radiotap");
dissector_add("wtap_encap", WTAP_ENCAP_IEEE_802_11_WLAN_RADIOTAP, radiotap_handle);
}
/*
* Editor modelines
*
* Local Variables:
* c-basic-offset: 4
* tab-width: 8
* indent-tabs-mode: t
* End:
*
* ex: set shiftwidth=4 tabstop=8 noexpandtab
* :indentSize=4:tabSize=8:noTabs=false:
*/
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