From: Rich Kulawiec <rsk@gsp.org> On Wed, May 06, 2015 at 03:30:01PM -0700, Scott Weeks wrote:
From: Rich Kulawiec <rsk@gsp.org>
The first rule in every firewall is of course "deny all" and subsequent rulesets permit only the traffic that is necessary. ------------------------------------
I think you got this backward? That way all traffic is blocked, so none is allowed through.
Nope, I said exactly what I intended (and what I do, in practice). Doing so forces one to understand in detail what traffic actually needs to pass in/out and to craft specific rules for it. This in turn helps avoid making mistake #1: The Six Dumbest Ideas in Computer Security http://www.ranum.com/security/computer_security/editorials/dumb/ ----------------------------------------------------- After reading your emails all these years, I figured you meant it the way you wrote it. When you wrote "...subsequent rulesets permit only the traffic that is necessary" I misunderstood and thought you meant rules put in after the default deny, which are useless. But by subsequent rulesets you meant rule sets put in later in time and above the deny all not after the deny all. Small confusion over wording... :-) scott