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| Subject: | [Snort-sigs] (no subject) |
|---|---|
| Date: | Sat, 27 Nov 2004 16:08:40 -0700 |
"warwick ackfin" <warwick7th@gmail.com> wrote:
I can't seem to find a way to create a rule that will look for a logical negative. Basically I want to say "alert on any ICMP packet that *doesn't* have this content" where the content is the Microsoft or Linux ICMP type 0 implementation flavor.
alert icmp any any -> any any (msg:"my ICMP echo reply alert"; itype:0; content:!"foo"; content:!"bar";) (Section 3.5.1 of the snort manual.) P.S. I would suspect that in most cases it would be type 8, not type 0, that you want to look for. ------------------------------------------------------- SF email is sponsored by - The IT Product Guide Read honest & candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://productguide.itmanagersjournal.com/ _______________________________________________ Snort-sigs mailing list Snort-sigs@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/snort-sigs
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