[RFC] programmatic IDS routing

[Klaus Heinrich Kiwi]

> > So the admin would create the rule he wants, create a unique key and tell
> > the IDS what the key is and how it should react when it sees a record with
> > that key.
> 
> Yes. What I want to do is also say that if you create your unique key a 
> certain way, you get this additional benefit of realtime alerting or 
> correlation. if you choose not to, then its treated as any other event

I agree with Steve's compromise with speed, but maybe there's no way out
of using hashes or linked lists in the general case.

What if a message is important not only for the IDS plugin but also to a
fictional 'real-time compliance reporting' plugin - both wanting to use
the key field to carry special things, and in the same event:
type=USER_ACCT msg=... key=ids-file-high,sox-fault-med,actual_key

The plug-ins would need to check if their specific identifier is present
not only in the first 4 bytes, but after every comma.

If it's desirable to support the general case, instead of putting
everything in one single 'key' field, maybe having an index just like
execve arguments:
type=USER_ACCT msg=... key[0]=ids-file-high key[1]=sox-fault-med
key[2]=actual_key

Still need to iterate through all keys in the worst case, but the
plugins could individually chose between having the rules hardcoded (for
speed) or configurable.

 -Klaus
-- 
Klaus Heinrich Kiwi
Security Development - IBM Linux Technology Center