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The radiotap parser read the TSFT field without applying the spec's 8-byte alignment. With extended present-words (EXT bit set, e.g. on ath9k_htc), the field chain shifts by 4 bytes and the channel field reads 0, causing every frame to bail with 'bad reported frequency' and no 802.11 data to be recorded.
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Fixes #1498
What
Add the radiotap-spec-required 8-byte alignment before the TSFT field in
tap/src/protocols/parsers/dot11/dot11_header_parser.rs. When the present-flags word carries the EXT bit (e.g.ath9k_htcemits two present words), the field area starts at a 4-byte-misaligned offset; without the alignment, the channel field is read 4 bytes early and lands on0x0000, tripping thefrequency == 0bail — discarding every frame.Why
See #1498 for full detail. Symptom: a tap only ever records the single strongest AP while raw
tcpdumpon the same interface sees dozens; deauth/disconnect timeline events never fire because frames never make it past the header parser.Verification
Tested with a USB Atheros AR9271 (
ath9k_htc) tap on Ubuntu, pinned channel: