[rt2x00-users] Alignment, padding and IV/ICV

[Gertjan van Wingerde]

On 12/01/09 20:06, Ivo van Doorn wrote:
>> RX path analysis (this does not fully represent is doing exactly, but
>> it's only for understanding) :
>>
>> 1. we receive a packet from HW in rt2x00usb_interrupt_rxdone
>> 2. we remove header (RXINFO+RXWI) & footer (RXD+USB pad) in
>> rt2800usb_fill_rxdone
>> 3. we remove L2 pad between 802.11 header and 802.11 payload if applicable
>> 4. we set skb->len to rxdesc.size to remove padding at the end of the frame
>> 5. we reinsert IV between header/payload and ICV at the end (after
>> payload) if applicable
>> 6. we align payload : it seems that mac80211 already takes care of that
> 
> As far as I know mac80211 will WARN_ON() when the payload is aligned,
> but will not perform the alignment itself. That is why rt2x00lib is doing it.

Actually, nowadays, mac80211 does perform the alignment itself. And the WARN_ON
is being removed as well (patch to do it has been approved yesterday).

---
Gertjan