On Nov 26, 2007 6:35 PM, Johannes Berg <johannes@xxxxxxxxxxxxxxxx> wrote:
>
> On Mon, 2007-11-26 at 16:14 +0200, Ron Rindjunsky wrote:
> > This patch adds the ability to receive and handle A-MSDU frames.
> >
> > Signed-off-by: Ron Rindjunsky <ron.rindjunsky@xxxxxxxxx>
>
> Acked-by: Johannes Berg <johannes@xxxxxxxxxxxxxxxx>
>
> Thanks for your patience on this. I have another question that is
> identical in the other code and that we should, if necessary, fix in a
> separate patch to fix both instances of this:
>
>
> > + payload = frame->data;
> > + ethertype = (payload[6] << 8) | payload[7];
> > +
> > + if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
> [...]
> > + } else {
> > + memcpy(skb_push(frame, sizeof(__be16)), &len,
> > + sizeof(__be16));
> > + memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
> > + memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
>
> Here, as well as in the regular data frame handler, we push the length
> of the frame into the ethernet header. Later then, eth_type_trans() will
> load up the skb->protocol field. The thing I'm not entirely sure about
> is this: We can have frames longer than 1536 bytes, but only if the
> length is smaller than 1536 does eth_type_trans() assume that it's a
> length, if we have a frame longer won't it go wrong? I haven't quite
> managed to wrap my head around the rules for wrapping data into an
> 802.11 frame nor in an 802.3 setting so this may be totally incorrect.
>
Just grabbed this from wikipedia
'
values of that field between 0 and 1500 indicated the use of the
original 802.3 Ethernet format with a length field, while values of
1536 decimal (0600 hexadecimal) and greater indicated the use of the
DIX frame format with an EtherType sub-protocol identifier
'
> johannes
>
-
To unsubscribe from this list: send the line "unsubscribe linux-wireless" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
