How do I test for NO tcp flags being set, in ipfilter? (repost)

Danny Pansters danny at ricin.com
Tue Mar 2 10:33:17 PST 2004


On Tuesday 02 March 2004 18:27, Shaun T. Erickson wrote:
> How do I test for NO tcp flags being set, in ipfilter?

You can filter on TCP flags but seems to me what you really mean is how to 
check for no TCP options ("nop") rather than no flags:

'with opt nop' is a syntax that should work.

WRT flags, it's my understanding that every TCP packet has at least the A or S 
flag set. 


HTH,

Dan



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