wifi: mac80211: Use struct instead of macro for PREQ frame

The existing PREQ_IE_* macros access HWMP PREQ frame fields via hardcoded
byte offsets. When the AE (Address Extension) flag is set, an additional
6 bytes appear mid-frame, and the macros handle this with conditional
arithmetic (e.g., AE_F_SET(x) ? x + N+6 : x + N). This approach
obscures the frame layout and is prone to miscalculation.

Introduce typed packed C structs to represent the PREQ frame layout:
  - ieee80211_mesh_hwmp_preq_top: fixed fields before the optional AE
    address
  - ieee80211_mesh_hwmp_preq_bottom: fields after the optional AE address
  - ieee80211_mesh_hwmp_preq_target: per-target fields

Add ieee80211_mesh_hwmp_preq_get_bottom() to locate the bottom struct
correctly based on whether the AE flag is set.

This preparatory refactoring is needed to fix a 2-byte overread of
target_addr in hwmp_preq_frame_process() when AE is enabled, which is
addressed in a subsequent patch.

Signed-off-by: Masashi Honma <masashi.honma@gmail.com>
Link: https://patch.msgid.link/20260529230952.124754-1-masashi.honma@gmail.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

0 files changed, 0 insertions, 0 deletions