+/* A generic radio capture format is desirable. It must be
+ * rigidly defined (e.g., units for fields should be given),
+ * and easily extensible.
+ *
+ * The following is an 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.
+ */
+
+/*
+ * The radio capture header precedes the 802.11 header.
+ *
+ * Note well: all radiotap fields are little-endian.
+ */
+struct ieee80211_radiotap_header {
+ nd_uint8_t it_version; /* Version 0. Only increases
+ * for drastic changes,
+ * introduction of compatible
+ * new fields does not count.
+ */
+ nd_uint8_t it_pad;
+ nd_uint16_t it_len; /* length of the whole
+ * header in bytes, including
+ * it_version, it_pad,
+ * it_len, and data fields.
+ */
+ nd_uint32_t 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 uint64_t 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 uint16_t MHz, bitmap
+ *
+ * Tx/Rx frequency in MHz, followed by flags (see below).
+ * Note that IEEE80211_RADIOTAP_XCHANNEL must be used to
+ * represent an HT channel as there is not enough room in
+ * the flags word.
+ *
+ * IEEE80211_RADIOTAP_FHSS uint16_t see below
+ *
+ * For frequency-hopping radios, the hop set (first byte)
+ * and pattern (second byte).
+ *
+ * IEEE80211_RADIOTAP_RATE uint8_t 500kb/s or index
+ *
+ * Tx/Rx data rate. If bit 0x80 is set then it represents an
+ * an MCS index and not an IEEE rate.
+ *
+ * IEEE80211_RADIOTAP_DBM_ANTSIGNAL int8_t decibels from
+ * one milliwatt (dBm)
+ *
+ * RF signal power at the antenna, decibel difference from
+ * one milliwatt.
+ *
+ * IEEE80211_RADIOTAP_DBM_ANTNOISE int8_t decibels from
+ * one milliwatt (dBm)
+ *
+ * RF noise power at the antenna, decibel difference from one
+ * milliwatt.
+ *
+ * IEEE80211_RADIOTAP_DB_ANTSIGNAL uint8_t decibel (dB)
+ *
+ * RF signal power at the antenna, decibel difference from an
+ * arbitrary, fixed reference.
+ *
+ * IEEE80211_RADIOTAP_DB_ANTNOISE uint8_t decibel (dB)
+ *
+ * RF noise power at the antenna, decibel difference from an
+ * arbitrary, fixed reference point.
+ *
+ * IEEE80211_RADIOTAP_LOCK_QUALITY uint16_t 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 uint16_t 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 uint16_t 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 int8_t 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 uint8_t bitmap
+ *
+ * Properties of transmitted and received frames. See flags
+ * defined below.
+ *
+ * IEEE80211_RADIOTAP_ANTENNA uint8_t antenna index
+ *
+ * Unitless indication of the Rx/Tx antenna for this packet.
+ * The first antenna is antenna 0.
+ *
+ * IEEE80211_RADIOTAP_RX_FLAGS uint16_t bitmap
+ *
+ * Properties of received frames. See flags defined below.
+ *
+ * IEEE80211_RADIOTAP_XCHANNEL uint32_t bitmap
+ * uint16_t MHz
+ * uint8_t channel number
+ * uint8_t .5 dBm
+ *
+ * Extended channel specification: flags (see below) followed by
+ * frequency in MHz, the corresponding IEEE channel number, and
+ * finally the maximum regulatory transmit power cap in .5 dBm
+ * units. This property supersedes IEEE80211_RADIOTAP_CHANNEL
+ * and only one of the two should be present.
+ *
+ * IEEE80211_RADIOTAP_MCS uint8_t known
+ * uint8_t flags
+ * uint8_t mcs
+ *
+ * Bitset indicating which fields have known values, followed
+ * by bitset of flag values, followed by the MCS rate index as
+ * in IEEE 802.11n.
+ *
+ *
+ * IEEE80211_RADIOTAP_AMPDU_STATUS u32, u16, u8, u8 unitless
+ *
+ * Contains the AMPDU information for the subframe.
+ *
+ * IEEE80211_RADIOTAP_VHT u16, u8, u8, u8[4], u8, u8, u16
+ *
+ * Contains VHT information about this frame.
+ *
+ * IEEE80211_RADIOTAP_VENDOR_NAMESPACE
+ * uint8_t OUI[3]
+ * uint8_t subspace
+ * uint16_t length
+ *
+ * The Vendor Namespace Field contains three sub-fields. The first
+ * sub-field is 3 bytes long. It contains the vendor's IEEE 802
+ * Organizationally Unique Identifier (OUI). The fourth byte is a
+ * vendor-specific "namespace selector."
+ *
+ */
+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,
+ /* NB: gap for netbsd definitions */
+ IEEE80211_RADIOTAP_XCHANNEL = 18,
+ IEEE80211_RADIOTAP_MCS = 19,
+ IEEE80211_RADIOTAP_AMPDU_STATUS = 20,
+ IEEE80211_RADIOTAP_VHT = 21,
+ IEEE80211_RADIOTAP_NAMESPACE = 29,
+ IEEE80211_RADIOTAP_VENDOR_NAMESPACE = 30,
+ IEEE80211_RADIOTAP_EXT = 31
+};
+
+/* channel attributes */
+#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, borrowed from Ethereal */
+#define IEEE80211_CHAN_A \
+ (IEEE80211_CHAN_5GHZ | IEEE80211_CHAN_OFDM)
+#define IEEE80211_CHAN_B \
+ (IEEE80211_CHAN_2GHZ | IEEE80211_CHAN_CCK)
+#define IEEE80211_CHAN_G \
+ (IEEE80211_CHAN_2GHZ | IEEE80211_CHAN_DYN)
+#define IEEE80211_CHAN_TA \
+ (IEEE80211_CHAN_5GHZ | IEEE80211_CHAN_OFDM | IEEE80211_CHAN_TURBO)
+#define IEEE80211_CHAN_TG \
+ (IEEE80211_CHAN_2GHZ | IEEE80211_CHAN_DYN | 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 */
+
+/* For IEEE80211_RADIOTAP_RX_FLAGS */
+#define IEEE80211_RADIOTAP_F_RX_BADFCS 0x0001 /* frame failed crc check */
+#define IEEE80211_RADIOTAP_F_RX_PLCP_CRC 0x0002 /* frame failed PLCP CRC check */
+
+/* For IEEE80211_RADIOTAP_MCS known */
+#define IEEE80211_RADIOTAP_MCS_BANDWIDTH_KNOWN 0x01
+#define IEEE80211_RADIOTAP_MCS_MCS_INDEX_KNOWN 0x02 /* MCS index field */
+#define IEEE80211_RADIOTAP_MCS_GUARD_INTERVAL_KNOWN 0x04
+#define IEEE80211_RADIOTAP_MCS_HT_FORMAT_KNOWN 0x08
+#define IEEE80211_RADIOTAP_MCS_FEC_TYPE_KNOWN 0x10
+#define IEEE80211_RADIOTAP_MCS_STBC_KNOWN 0x20
+#define IEEE80211_RADIOTAP_MCS_NESS_KNOWN 0x40
+#define IEEE80211_RADIOTAP_MCS_NESS_BIT_1 0x80
+
+/* For IEEE80211_RADIOTAP_MCS flags */
+#define IEEE80211_RADIOTAP_MCS_BANDWIDTH_MASK 0x03
+#define IEEE80211_RADIOTAP_MCS_BANDWIDTH_20 0
+#define IEEE80211_RADIOTAP_MCS_BANDWIDTH_40 1
+#define IEEE80211_RADIOTAP_MCS_BANDWIDTH_20L 2
+#define IEEE80211_RADIOTAP_MCS_BANDWIDTH_20U 3
+#define IEEE80211_RADIOTAP_MCS_SHORT_GI 0x04 /* short guard interval */
+#define IEEE80211_RADIOTAP_MCS_HT_GREENFIELD 0x08
+#define IEEE80211_RADIOTAP_MCS_FEC_LDPC 0x10
+#define IEEE80211_RADIOTAP_MCS_STBC_MASK 0x60
+#define IEEE80211_RADIOTAP_MCS_STBC_1 1
+#define IEEE80211_RADIOTAP_MCS_STBC_2 2
+#define IEEE80211_RADIOTAP_MCS_STBC_3 3
+#define IEEE80211_RADIOTAP_MCS_STBC_SHIFT 5
+#define IEEE80211_RADIOTAP_MCS_NESS_BIT_0 0x80
+
+/* For IEEE80211_RADIOTAP_AMPDU_STATUS */
+#define IEEE80211_RADIOTAP_AMPDU_REPORT_ZEROLEN 0x0001
+#define IEEE80211_RADIOTAP_AMPDU_IS_ZEROLEN 0x0002
+#define IEEE80211_RADIOTAP_AMPDU_LAST_KNOWN 0x0004
+#define IEEE80211_RADIOTAP_AMPDU_IS_LAST 0x0008
+#define IEEE80211_RADIOTAP_AMPDU_DELIM_CRC_ERR 0x0010
+#define IEEE80211_RADIOTAP_AMPDU_DELIM_CRC_KNOWN 0x0020
+
+/* For IEEE80211_RADIOTAP_VHT known */
+#define IEEE80211_RADIOTAP_VHT_STBC_KNOWN 0x0001
+#define IEEE80211_RADIOTAP_VHT_TXOP_PS_NA_KNOWN 0x0002
+#define IEEE80211_RADIOTAP_VHT_GUARD_INTERVAL_KNOWN 0x0004
+#define IEEE80211_RADIOTAP_VHT_SGI_NSYM_DIS_KNOWN 0x0008
+#define IEEE80211_RADIOTAP_VHT_LDPC_EXTRA_OFDM_SYM_KNOWN 0x0010
+#define IEEE80211_RADIOTAP_VHT_BEAMFORMED_KNOWN 0x0020
+#define IEEE80211_RADIOTAP_VHT_BANDWIDTH_KNOWN 0x0040
+#define IEEE80211_RADIOTAP_VHT_GROUP_ID_KNOWN 0x0080
+#define IEEE80211_RADIOTAP_VHT_PARTIAL_AID_KNOWN 0x0100
+
+/* For IEEE80211_RADIOTAP_VHT flags */
+#define IEEE80211_RADIOTAP_VHT_STBC 0x01
+#define IEEE80211_RADIOTAP_VHT_TXOP_PS_NA 0x02
+#define IEEE80211_RADIOTAP_VHT_SHORT_GI 0x04
+#define IEEE80211_RADIOTAP_VHT_SGI_NSYM_M10_9 0x08
+#define IEEE80211_RADIOTAP_VHT_LDPC_EXTRA_OFDM_SYM 0x10
+#define IEEE80211_RADIOTAP_VHT_BEAMFORMED 0x20
+
+#define IEEE80211_RADIOTAP_VHT_BANDWIDTH_MASK 0x1f
+
+#define IEEE80211_RADIOTAP_VHT_NSS_MASK 0x0f
+#define IEEE80211_RADIOTAP_VHT_MCS_MASK 0xf0
+#define IEEE80211_RADIOTAP_VHT_MCS_SHIFT 4
+
+#define IEEE80211_RADIOTAP_CODING_LDPC_USERn 0x01
+
+#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 IS_CHAN_FHSS(flags) \
+ ((flags & IEEE80211_CHAN_FHSS) == IEEE80211_CHAN_FHSS)
+#define IS_CHAN_A(flags) \
+ ((flags & IEEE80211_CHAN_A) == IEEE80211_CHAN_A)
+#define IS_CHAN_B(flags) \
+ ((flags & IEEE80211_CHAN_B) == IEEE80211_CHAN_B)
+#define IS_CHAN_PUREG(flags) \
+ ((flags & IEEE80211_CHAN_PUREG) == IEEE80211_CHAN_PUREG)
+#define IS_CHAN_G(flags) \
+ ((flags & IEEE80211_CHAN_G) == IEEE80211_CHAN_G)
+#define IS_CHAN_ANYG(flags) \
+ (IS_CHAN_PUREG(flags) || IS_CHAN_G(flags))
+
+static void
+print_chaninfo(netdissect_options *ndo,
+ uint16_t freq, uint32_t flags, uint32_t presentflags)
+{
+ ND_PRINT("%u MHz", freq);
+ if (presentflags & (1 << IEEE80211_RADIOTAP_MCS)) {
+ /*
+ * We have the MCS field, so this is 11n, regardless
+ * of what the channel flags say.
+ */
+ ND_PRINT(" 11n");
+ } else {
+ if (IS_CHAN_FHSS(flags))
+ ND_PRINT(" FHSS");
+ if (IS_CHAN_A(flags)) {
+ if (flags & IEEE80211_CHAN_HALF)
+ ND_PRINT(" 11a/10Mhz");
+ else if (flags & IEEE80211_CHAN_QUARTER)
+ ND_PRINT(" 11a/5Mhz");
+ else
+ ND_PRINT(" 11a");
+ }
+ if (IS_CHAN_ANYG(flags)) {
+ if (flags & IEEE80211_CHAN_HALF)
+ ND_PRINT(" 11g/10Mhz");
+ else if (flags & IEEE80211_CHAN_QUARTER)
+ ND_PRINT(" 11g/5Mhz");
+ else
+ ND_PRINT(" 11g");
+ } else if (IS_CHAN_B(flags))
+ ND_PRINT(" 11b");
+ if (flags & IEEE80211_CHAN_TURBO)
+ ND_PRINT(" Turbo");
+ }
+ /*
+ * These apply to 11n.
+ */
+ if (flags & IEEE80211_CHAN_HT20)
+ ND_PRINT(" ht/20");
+ else if (flags & IEEE80211_CHAN_HT40D)
+ ND_PRINT(" ht/40-");
+ else if (flags & IEEE80211_CHAN_HT40U)
+ ND_PRINT(" ht/40+");
+ ND_PRINT(" ");
+}
+
+static int
+print_radiotap_field(netdissect_options *ndo,
+ struct cpack_state *s, uint32_t bit, uint8_t *flagsp,
+ uint32_t presentflags)
+{
+ u_int i;
projects / tcpdump / blobdiff