Re: DNS hardening, was Re: Dan Kaminsky

2009-08-10 Thread Douglas Otis
This was responded to on the DNSEXT mailing list. Sorry, but your question was accidentally attributed to Paul who forwarded the message. DNSEXT Archive: http://ops.ietf.org/lists/namedroppers/ -Doug

Re: DNS hardening, was Re: Dan Kaminsky

2009-08-07 Thread Steven M. Bellovin
On Thu, 06 Aug 2009 06:51:24 + Paul Vixie vi...@isc.org wrote: Christopher Morrow morrowc.li...@gmail.com writes: how does SCTP ensure against spoofed or reflected attacks? there is no server side protocol control block required in SCTP. someone sends you a create association

Re: DNS hardening, was Re: Dan Kaminsky

2009-08-06 Thread Paul Vixie
Christopher Morrow morrowc.li...@gmail.com writes: how does SCTP ensure against spoofed or reflected attacks? there is no server side protocol control block required in SCTP. someone sends you a create association request, you send back a ok, here's your cookie and you're done until/unless

Re: DNS hardening, was Re: Dan Kaminsky

2009-08-06 Thread Florian Weimer
* Douglas Otis: Establishing SCTP as a preferred DNS transport offers a safe harbor for major ISPs. SCTP is not a suitable transport for DNS, for several reasons: Existing SCTP stacks are not particularly robust (far less than TCP). The number of bugs still found in them is rather large.

Re: DNS hardening, was Re: Dan Kaminsky

2009-08-06 Thread Florian Weimer
* Paul Vixie: there is no server side protocol control block required in SCTP. SCTP needs per-peer state for congestion control and retransmission. someone sends you a create association request, you send back a ok, here's your cookie and you're done until/unless they come back and say ok,

Re: DNS hardening, was Re: Dan Kaminsky

2009-08-06 Thread Florian Weimer
* John Levine: 3) Random case in queries, e.g. GooGLe.CoM This does not work well without additional changes because google.com can be spoofed with responses to 123352123.com (or even 123352123.). Unbound strives to implement the necessary changes, some of which are also required if you want

Re: DNS hardening, was Re: Dan Kaminsky

2009-08-06 Thread Paul Jakma
On Thu, 6 Aug 2009, Florian Weimer wrote: This doesn't seem possible with current SCTP because the heartbeat rate quickly adds up and overloads servers further upstream. It also does not work on UNIX-like system where processes are short-lived and get a fresh stub resolver each time they are

Re: DNS hardening, was Re: Dan Kaminsky

2009-08-06 Thread Christopher Morrow
On Thu, Aug 6, 2009 at 2:51 AM, Paul Vixievi...@isc.org wrote: Christopher Morrow morrowc.li...@gmail.com writes: how does SCTP ensure against spoofed or reflected attacks? there is no server side protocol control block required in SCTP.  someone sends you a create association request, you

Re: DNS hardening, was Re: Dan Kaminsky

2009-08-06 Thread Paul Vixie
note, i went off-topic in my previous note, and i'll be answering florian on namedroppers@ since it's not operational. chris's note was operational: Date: Thu, 6 Aug 2009 10:18:11 -0400 From: Christopher Morrow morrowc.li...@gmail.com awesome, how does that work with devices in the

Re: DNS hardening, was Re: Dan Kaminsky

2009-08-06 Thread Ross Vandegrift
On Thu, Aug 06, 2009 at 03:16:25PM +, Paul Vixie wrote: ...: Do loadbalancers, or loadbalanced deployments, deal with this properly? (loadbalancers like F5, citrix, radware, cisco, etc...) as far as i know, no loadbalancer understands SCTP today. if they can be made to pass SCTP

Re: DNS hardening, was Re: Dan Kaminsky

2009-08-06 Thread Christopher Morrow
On Thu, Aug 6, 2009 at 11:16 AM, Paul Vixievi...@isc.org wrote: note, i went off-topic in my previous note, and i'll be answering florian on namedroppers@ since it's not operational.  chris's note was operational: Date: Thu, 6 Aug 2009 10:18:11 -0400 From: Christopher Morrow

Re: DNS hardening, was Re: Dan Kaminsky

2009-08-05 Thread bert hubert
On Wed, Aug 5, 2009 at 6:48 PM, John Levinejo...@iecc.com wrote: 3) Random case in queries, e.g. GooGLe.CoM 4) Ask twice (with different values for the first three hacks) and compare the answers I presume everyone is doing the first two.  Any experience with the other two to report? 3

Re: DNS hardening, was Re: Dan Kaminsky

2009-08-05 Thread Phil Regnauld
bert hubert (bert.hubert) writes: 5 is 'edns ping', but it was effectively blocked because people thought DNSSEC would be easier to do, or demanded that EDNS PING (http://edns-ping.org) would offer everything that DNSSEC offered. I'm surprised you failed to mention

Re: DNS hardening, was Re: Dan Kaminsky

2009-08-05 Thread Douglas Otis
On 8/5/09 9:48 AM, John Levine wrote: Other than DNSSEC, I'm aware of these relatively simple hacks to add entropy to DNS queries. 1) Random query ID 2) Random source port 3) Random case in queries, e.g. GooGLe.CoM 4) Ask twice (with different values for the first three hacks) and compare

Re: DNS hardening, was Re: Dan Kaminsky

2009-08-05 Thread Roland Dobbins
On Aug 6, 2009, at 1:12 AM, Douglas Otis wrote: Having major providers support the SCTP option will mitigate disruptions caused by DNS DDoS attacks using less resources. Can you elaborate on this (or are you referring to removing the spoofing vector?)?

RE: DNS hardening, was Re: Dan Kaminsky

2009-08-05 Thread Skywing
Levine jo...@iecc.com Cc: nanog@nanog.org nanog@nanog.org Subject: Re: DNS hardening, was Re: Dan Kaminsky On 8/5/09 9:48 AM, John Levine wrote: Other than DNSSEC, I'm aware of these relatively simple hacks to add entropy to DNS queries. 1) Random query ID 2) Random source port 3) Random

Re: DNS hardening, was Re: Dan Kaminsky

2009-08-05 Thread John R. Levine
5 is 'edns ping', but it was effectively blocked because people thought DNSSEC would be easier to do, or demanded that EDNS PING (http://edns-ping.org) would offer everything that DNSSEC offered. I'm surprised you failed to mention http://dnscurve.org/crypto.html, which is

Re: DNS hardening, was Re: Dan Kaminsky

2009-08-05 Thread John R. Levine
3 works, but offers zero protection against 'kaminsky spoofing the root' since you can't fold the case of 123456789.. And the root is the goal. Good point. 5) Download your own copy of the root zone every few days from http://www.internic.net/domain/, check the signature if you can find the

Re: DNS hardening, was Re: Dan Kaminsky

2009-08-05 Thread Douglas Otis
On 8/5/09 11:38 AM, Skywing wrote: That is, of course, assuming that SCTP implementations someday clean up their act a bit. I'm not so sure I'd suggest that they're really ready for prime time at this point. SCTP DNS would be intended for ISPs validating DNS where there would be fewer

Re: DNS hardening, was Re: Dan Kaminsky

2009-08-05 Thread Douglas Otis
On 8/5/09 11:31 AM, Roland Dobbins wrote: On Aug 6, 2009, at 1:12 AM, Douglas Otis wrote: Having major providers support the SCTP option will mitigate disruptions caused by DNS DDoS attacks using less resources. Can you elaborate on this (or are you referring to removing the spoofing

Re: DNS hardening, was Re: Dan Kaminsky

2009-08-05 Thread Christopher Morrow
On Wed, Aug 5, 2009 at 5:24 PM, Douglas Otisdo...@mail-abuse.org wrote: On 8/5/09 11:31 AM, Roland Dobbins wrote: On Aug 6, 2009, at 1:12 AM, Douglas Otis wrote: Having major providers support the SCTP option will mitigate disruptions caused by DNS DDoS attacks using less resources. Can

Re: DNS hardening, was Re: Dan Kaminsky

2009-08-05 Thread Steven M. Bellovin
On Wed, 5 Aug 2009 15:07:30 -0400 (EDT) John R. Levine jo...@iecc.com wrote: 5 is 'edns ping', but it was effectively blocked because people thought DNSSEC would be easier to do, or demanded that EDNS PING (http://edns-ping.org) would offer everything that DNSSEC offered. I'm

Re: DNS hardening, was Re: Dan Kaminsky

2009-08-05 Thread Douglas Otis
On 8/5/09 2:49 PM, Christopher Morrow wrote: and state-management seems like it won't be too much of a problem on that dns server... wait, yes it will. DNSSEC UDP will likely become problematic. This might be due to reflected attacks, fragmentation related congestion, or packet loss. When

Re: DNS hardening, was Re: Dan Kaminsky

2009-08-05 Thread Christopher Morrow
On Wed, Aug 5, 2009 at 6:53 PM, Douglas Otisdo...@mail-abuse.org wrote: On 8/5/09 2:49 PM, Christopher Morrow wrote: and state-management seems like it won't be too much of a problem on that dns server... wait, yes it will. DNSSEC UDP will likely become problematic.  This might be due to