Re: Performance improvement for NAT in IPFIREWALL

2003-07-03 Thread Achim Patzner
On Wed, Jul 02, 2003 at 08:48:27PM -0400, Chuck Swiger wrote: > >>"Since NAT actually adds no security, > >You're of the school that sez "what I tell you three times is true?" > It worked for Dorothy, right? :-) Well... If you only want to convince hillbillies it might be enough. Actually NAT ma

Re: Performance improvement for NAT in IPFIREWALL

2003-07-02 Thread Julian Elischer
On Thu, 3 Jul 2003, Clement Laforet wrote: > Hi, > > On Wed, 2 Jul 2003 18:39:42 -0500 (CDT) > Mike Silbersack <[EMAIL PROTECTED]> wrote: > > > > Comments? Suggestions? Vision? > > > > If you have some time to throw at the problem, you might consider > > using gprof on natd in order to determ

Re: Performance improvement for NAT in IPFIREWALL

2003-07-02 Thread Chuck Swiger
Mike Silbersack wrote: [ ... ] Please explain this point more. Say I have 1000 win 9x boxes connected to the internet with routable IPs and no firewall. How will placing them behind a NAT box make them less secure? "man natd" suggests that you've just enabled IP spoofing for the LAN: Y

Re: Performance improvement for NAT in IPFIREWALL

2003-07-02 Thread Chuck Swiger
Michael Sierchio wrote: Chuck Swiger wrote: [ ... ] Security is an ill-defined concept. I prefer to think in terms of mitigating risk. Sure, that works for me. In any case, deny_incoming offers some extra measure of security. Does it? Serious question, as none of the connections deny_incoming ma

Re: Performance improvement for NAT in IPFIREWALL

2003-07-02 Thread Mike Silbersack
On Wed, 2 Jul 2003, Chuck Swiger wrote: > By itself, NAT provides no benefit to security, and some implementations > actually reduce the security of the system compared with not running NAT. Let > me pull out a couple of quotes from various people: Please explain this point more. Say I have 10

Re: Performance improvement for NAT in IPFIREWALL

2003-07-02 Thread Michael Sierchio
Chuck Swiger wrote: To the extent that "security" is a matter of opinion, I guess that's all right: I'm not concerned if other people have different opinions than I do. Security is an ill-defined concept. I prefer to think in terms of mitigating risk. In any case, deny_incoming offers some extra

Re: Performance improvement for NAT in IPFIREWALL

2003-07-02 Thread Ruslan Ermilov
On Wed, Jul 02, 2003 at 07:06:25PM -0400, Chuck Swiger wrote: [...] > By itself, NAT provides no benefit to security, and some implementations > actually reduce the security of the system compared with not running NAT. > Our natd(8) contributes to security somewhat, by providing the -deny_incom

Re: Performance improvement for NAT in IPFIREWALL

2003-07-02 Thread Dean Strik
Michael Sierchio wrote: > Chuck Swiger wrote: > > >Many people are wrong, then. NAT is not a security feature. > > We simply disagree. Puh-leaze. Not this discussion again. Can we stay on topic please? -- Dean C. Strik Eindhoven University of Technology [EMAIL PROTECTED] | [EMAI

Re: Performance improvement for NAT in IPFIREWALL

2003-07-02 Thread Chuck Swiger
Michael Sierchio wrote: Chuck Swiger wrote: Many people are wrong, then. NAT is not a security feature. We simply disagree. To the extent that "security" is a matter of opinion, I guess that's all right: I'm not concerned if other people have different opinions than I do. To the extent that secu

Re: Performance improvement for NAT in IPFIREWALL

2003-07-02 Thread Clement Laforet
Hi, On Wed, 2 Jul 2003 18:39:42 -0500 (CDT) Mike Silbersack <[EMAIL PROTECTED]> wrote: > > Comments? Suggestions? Vision? > > If you have some time to throw at the problem, you might consider > using gprof on natd in order to determine what exactly about natd is > slow. As is commonly mentioned

Re: Performance improvement for NAT in IPFIREWALL

2003-07-02 Thread Mike Silbersack
On Wed, 2 Jul 2003, Michael Sierchio wrote: > Currently, performance w/divert sockets and natd in ipfirewall > on a compute-bound platform (ELAN-133MHz) shows ipfw+natd throughput > to be 50% of that offered by ipfilter+ipnat. > > Is there anything that can be done to speed up either the > perfor

Re: Performance improvement for NAT in IPFIREWALL

2003-07-02 Thread Michael Sierchio
Chuck Swiger wrote: Many people are wrong, then. NAT is not a security feature. We simply disagree. [ NAT sucks. In a very useful way, of course. Exogenous requirements may impose unreasonable constraints upon implementing the technically preferrable solution, just as "inept excess verbiage

Re: Performance improvement for NAT in IPFIREWALL

2003-07-02 Thread Michael Sierchio
Barney Wolff wrote: On Wed, Jul 02, 2003 at 11:44:14AM -0700, Michael Sierchio wrote: NAT is not a security feature, Many would disagree with that assertion. They would be wrong. Find a real security expert and ask. Clearly that would not be you. Both static and dynamic (or "hide") nat have secu

Re: Performance improvement for NAT in IPFIREWALL

2003-07-02 Thread Chuck Swiger
Michael Sierchio wrote: Barney Wolff wrote: NAT is not a security feature, Many would disagree with that assertion. Many people are wrong, then. NAT is not a security feature. Check the list archives of <[EMAIL PROTECTED]>... [ ... ] If you believe you need to NAT at even 1Gb, I'd look very hard

Re: Performance improvement for NAT in IPFIREWALL

2003-07-02 Thread Barney Wolff
On Wed, Jul 02, 2003 at 11:44:14AM -0700, Michael Sierchio wrote: > >NAT is not a security feature, > > Many would disagree with that assertion. They would be wrong. Find a real security expert and ask. ... > >But moving NAT into the kernel has great impact on kernel memory usage, > >which ne

Re: Performance improvement for NAT in IPFIREWALL

2003-07-02 Thread Michael Sierchio
Barney Wolff wrote: NAT is not a security feature, Many would disagree with that assertion. and should be used only where it is actually necessary to translate addresses, and as far towards the edge as possible. This is typically where firewalls are found. If you believe you need to NAT at even

Re: Performance improvement for NAT in IPFIREWALL

2003-07-02 Thread Barney Wolff
On Wed, Jul 02, 2003 at 10:31:10AM -0700, Michael Sierchio wrote: > > Currently, performance w/divert sockets and natd in ipfirewall > on a compute-bound platform (ELAN-133MHz) shows ipfw+natd throughput > to be 50% of that offered by ipfilter+ipnat. > > Is there anything that can be done to spee

Performance improvement for NAT in IPFIREWALL

2003-07-02 Thread Michael Sierchio
Currently, performance w/divert sockets and natd in ipfirewall on a compute-bound platform (ELAN-133MHz) shows ipfw+natd throughput to be 50% of that offered by ipfilter+ipnat. Is there anything that can be done to speed up either the performance of divert and natd? Alternatively, could network ad