[En-Nut-Discussion] IP Checksum calculation broken. Reenabled old algorithm for the meantime.

[Nathan Moore]

>
>
> I just discovered that the new IP checksum calculation which was
> introduced a few month ago is broken for some situations. I could not
> find a concrete reason so far, but I think it's an alignment question.
>

Years ago I was trying to squeeze performance out of Nut/OS on an
Atmega and fiddled with a gcc inline assembly checksum calculation
for it.  I'm sure that all targets could benefit from their own checksumming
routines for both performance and correctness (endian and alignment
issues).

This is a simple and often executed piece of code.

Nathan