On 01.12.2016 17:19, David Miller wrote:
> Saying that ntuple filters can handle the early drop use case doesn't
> take into consideration the nature of the tables (hundreds of
> thousands of "evil" IP addresses), whether hardware can actually
> handle that (it can't), and whether simple IP address matching is the
> full extent of it (it isn't).
Yes, that is why you certainly use ntuple filters in combination with
some kind of high level business logic in user space.
I have to check but am pretty sure you can't even do the simplest thing
in XDP, parsing the apexes of DNS packets and checking them against a
hash table, because the program won't pass the verifier.