Re: Scanning IP6 packets

[Darren Reed <darrenr () netbsd org>]

On 13/11/2013 7:15 PM, Guy Harris wrote:
> ...
> Or write your own filter expression that looks at the link-layer header to detect IPv6 packets, skips past the IPv6 
> header (you won't be able to handle extension headers, as that involves looping, and the libpcap filter language 
> doesn't support that), and then loads the appropriate value from the TCP header based on that.
>
> There is no easy solution.

Something that I'm working on is a design & implementation of BPF (v2) that
incorporates instructions that are specifically designed to deal with headers
that are chained together in this fashion. In its current form, BPF (v1) is
not that IPv6 friendly. Give me a week or two to back up a design with some
code that works (the parser and compiler bit are the tricky pieces.)

Darren
.

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