[PATCH] Respect WG protocol reserved bytes

[Jason A. Donenfeld]

On 3/17/21, Laura Zelenku <laura.zelenku at wandera.com> wrote:
> If the client send some data in reserved bytes you will have logs full of
> errors because the message gets type from 4 bytes instead of 1 byte (like it
> is in protocol description).
> I would like implementation respects protocol -
> https://www.wireguard.com/papers/wireguard.pdf . Yes, in our project we use
> reserved bytes.
>
> I know that when there are zeros in reserved bytes, everything is correct.
> But if you receive some non-zero value in reserved bytes?
>

Aaron is right.

Those bytes MUST be set to zero. Otherwise you're now implementing a
different protocol. Do not use reserved bytes. They are not reserved
for you.