Wireshark-dev: Re: [Wireshark-dev] Regarding display filter- how to redesign code to incorporat

From: Guy Harris <guy@xxxxxxxxxxxx>
Date: Fri, 18 Apr 2014 14:37:14 -0700
On Apr 18, 2014, at 2:13 PM, Ateeth Kumar Thirukkovulur <athirukkovulur@xxxxxx> wrote:

> I want to know if there is any way to redesign the wireshark filter to incorporate algebraic expressions instead of filtering using protocols?

Filtering *already* uses more than just protocols - it uses fields from protocols, for example, "ip.src == 127.0.0.1" or "ip.len == 1024".

An algebraic expression, in order to be a *useful* filter, would have to incorporate variables of some sort; neither "(5 + 3)*2 == 16" nor "(5 + 3)*2 == 17" are particularly interesting filters (the first one would match all packets, the second one would match no packets).

So you'd need some sort of variables; if the variables are fields from protocols, adding support for arithmetic operators, for example, "foo.len1 - foo.len2 == 30", isn't really a "redesign", it's just an enhancement.

Is that what you're talking about?