RE: hat tip to .gov hostmasters
Pretty soon we'll have a blacklist of DNS servers that don't support DNSSEC for .gov. =) Frank -Original Message- From: Chris Owen [mailto:[EMAIL PROTECTED] Sent: Monday, September 22, 2008 10:02 AM To: NANOG list Subject: Re: hat tip to .gov hostmasters -BEGIN PGP SIGNED MESSAGE- Hash: SHA1 On Sep 22, 2008, at 9:59 AM, Simon Vallet wrote: On Mon, 22 Sep 2008 10:52:42 -0400 Jason Frisvold [EMAIL PROTECTED] wrote: I'm not much up on DNSSEC, but don't you need to be using a resolver that recognizes DNSSEC in order for this to be useful? You do -- and last time I checked few native resolvers actually did : glibc doesn't, and I'd be surprised if the Windows resolver does Chicken, meet egg. I think the point of the original post is that one end or the other has to start things. At least we have one US zone doing something on the server end of things. Chris Chris Owen ~ Garden City (620) 275-1900 ~ Lottery (noun): President ~ Wichita (316) 858-3000 ~A stupidity tax Hubris Communications Inc www.hubris.net -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.9 (Darwin) Comment: Public Key: http://home.hubris.net/owenc/pgpkey.txt Comment: Public Key ID: 0xB513D9DD iEYEARECAAYFAkjXs30ACgkQElUlCLUT2d0SfwCbB8FQ4izN061GoQQMl3fkq+NT ga0AoJnwGG8PfBs5PaziRB6m0NQBuZwc =68dm -END PGP SIGNATURE-
Re: hat tip to .gov hostmasters
On Mon, Sep 22, 2008 at 10:34 AM, Scott Francis [EMAIL PROTECTED] wrote: nice to see a wholesale DNSSEC rollout underway (I must confess to being a little surprised at the source, too!). Granted, it's a much more manageable problem set than, say, .com - but if one US-controlled TLD can do it, hope is buoyed for a .com rollout sooner rather than later (although probably not much sooner :)). I'm not much up on DNSSEC, but don't you need to be using a resolver that recognizes DNSSEC in order for this to be useful? /sf -- Jason 'XenoPhage' Frisvold [EMAIL PROTECTED] http://blog.godshell.com
Re: hat tip to .gov hostmasters
* Jason Frisvold: On Mon, Sep 22, 2008 at 10:34 AM, Scott Francis [EMAIL PROTECTED] wrote: nice to see a wholesale DNSSEC rollout underway (I must confess to being a little surprised at the source, too!). Granted, it's a much more manageable problem set than, say, .com - but if one US-controlled TLD can do it, hope is buoyed for a .com rollout sooner rather than later (although probably not much sooner :)). I'm not much up on DNSSEC, but don't you need to be using a resolver that recognizes DNSSEC in order for this to be useful? Correct, you need a validating, security-aware stub resolver, or the ISP needs to validate the records for you. -- Florian Weimer[EMAIL PROTECTED] BFK edv-consulting GmbH http://www.bfk.de/ Kriegsstraße 100 tel: +49-721-96201-1 D-76133 Karlsruhe fax: +49-721-96201-99
Re: hat tip to .gov hostmasters
On Mon, 22 Sep 2008 10:52:42 -0400 Jason Frisvold [EMAIL PROTECTED] wrote: I'm not much up on DNSSEC, but don't you need to be using a resolver that recognizes DNSSEC in order for this to be useful? You do -- and last time I checked few native resolvers actually did : glibc doesn't, and I'd be surprised if the Windows resolver does Simon
Re: hat tip to .gov hostmasters
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 On Sep 22, 2008, at 9:59 AM, Simon Vallet wrote: On Mon, 22 Sep 2008 10:52:42 -0400 Jason Frisvold [EMAIL PROTECTED] wrote: I'm not much up on DNSSEC, but don't you need to be using a resolver that recognizes DNSSEC in order for this to be useful? You do -- and last time I checked few native resolvers actually did : glibc doesn't, and I'd be surprised if the Windows resolver does Chicken, meet egg. I think the point of the original post is that one end or the other has to start things. At least we have one US zone doing something on the server end of things. Chris Chris Owen ~ Garden City (620) 275-1900 ~ Lottery (noun): President ~ Wichita (316) 858-3000 ~A stupidity tax Hubris Communications Inc www.hubris.net -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.9 (Darwin) Comment: Public Key: http://home.hubris.net/owenc/pgpkey.txt Comment: Public Key ID: 0xB513D9DD iEYEARECAAYFAkjXs30ACgkQElUlCLUT2d0SfwCbB8FQ4izN061GoQQMl3fkq+NT ga0AoJnwGG8PfBs5PaziRB6m0NQBuZwc =68dm -END PGP SIGNATURE-
Re: hat tip to .gov hostmasters
Florian Weimer wrote: * Jason Frisvold: On Mon, Sep 22, 2008 at 10:34 AM, Scott Francis [EMAIL PROTECTED] wrote: nice to see a wholesale DNSSEC rollout underway (I must confess to being a little surprised at the source, too!). Granted, it's a much more manageable problem set than, say, .com - but if one US-controlled TLD can do it, hope is buoyed for a .com rollout sooner rather than later (although probably not much sooner :)). I'm not much up on DNSSEC, but don't you need to be using a resolver that recognizes DNSSEC in order for this to be useful? Correct, you need a validating, security-aware stub resolver, or the ISP needs to validate the records for you. In public space like .com, don't you need some kind of central trustworthy CA?
Re: hat tip to .gov hostmasters
* Colin Alston: Correct, you need a validating, security-aware stub resolver, or the ISP needs to validate the records for you. In public space like .com, don't you need some kind of central trustworthy CA? No, why would you? You need to trust the zone operator, and you need some trustworthy channel to exchange trust anchors at one point in time (a significant improvement compared to classic DNS, where you need a trustworthy channel all the time). -- Florian Weimer[EMAIL PROTECTED] BFK edv-consulting GmbH http://www.bfk.de/ Kriegsstraße 100 tel: +49-721-96201-1 D-76133 Karlsruhe fax: +49-721-96201-99
Re: hat tip to .gov hostmasters
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 On Mon, 22 Sep 2008 10:02:21 -0500 Chris Owen [EMAIL PROTECTED] wrote: Chicken, meet egg. I think the point of the original post is that one end or the other has to start things. At least we have one US zone doing something on the server end of things. I totally agree on that, but wanted to point out that there still is some work be done. The folks at NLnet do have a nice DNSSEC implementation, though, as well as the BIND library. Simon -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.9 (GNU/Linux) iEYEARECAAYFAkjXtWUACgkQccZs6oMJsYR5XQCbB6e92xTcaR2ijn0DcAALdswA 358AmQH36qg/fBRGxJIFS4Alm4sAKF9w =7JfR -END PGP SIGNATURE-
RE: hat tip to .gov hostmasters
Correct, you need a validating, security-aware stub resolver, or the ISP needs to validate the records for you. That would defeat the entire purpose of using DNSSEC. In order for DNSSEC to actually provide any improvement in security whatsoever, the ROOT ZONE (.) needs to be signed, and every delegation up the chain needs to be signed. And EVERY resolver (whether recursive or local on host) needs to understand and enforce DNSSEC. If even one delegation is unsigned or even one resolver does not enforce DNSSEC, then, from an actual security perspective, you will be far worse off than you are now. Until such time as EVERY SINGLE DOMAIN including the root is signed and every single DNS Server and resolver (including the local host resolvers) understand and enforce DNSSEC you should realize that DNSSEC does nothing for you whatsoever except give the uneducated a false sense of security. It is likely that IPv48 will be deployed long before DNSSEC is implemented.
RE: hat tip to .gov hostmasters
DNSSEC is not a PKI. There are no CAs and no X.509 certificates. It's a chain of trust that can be validated using public/private key pairs. OK, that's oversimplification but you get the idea. While we wait for applications to become DNSSEC-aware, if your local DNS server can be trusted (a big if of course) then it can proxy the DNSSEC awareness for you. Since nearly everybody trusts a local DNS server to resolve queries, then making that server DNSSEC aware is an enormous step forward, even if the actual applications and operating systems on end-user computers are not fully DNSSEC-aware and won't be for many years to come. Marc -Original Message- From: Florian Weimer [mailto:[EMAIL PROTECTED] Sent: Monday, September 22, 2008 11:10 AM To: Colin Alston Cc: nanog@nanog.org Subject: Re: hat tip to .gov hostmasters * Colin Alston: Correct, you need a validating, security-aware stub resolver, or the ISP needs to validate the records for you. In public space like .com, don't you need some kind of central trustworthy CA? No, why would you? You need to trust the zone operator, and you need some trustworthy channel to exchange trust anchors at one point in time (a significant improvement compared to classic DNS, where you need a trustworthy channel all the time). -- Florian Weimer[EMAIL PROTECTED] BFK edv-consulting GmbH http://www.bfk.de/ Kriegsstraße 100 tel: +49-721-96201-1 D-76133 Karlsruhe fax: +49-721-96201-99
Re: hat tip to .gov hostmasters
On Mon, Sep 22, 2008 at 10:52:42AM -0400, Jason Frisvold wrote: On Mon, Sep 22, 2008 at 10:34 AM, Scott Francis [EMAIL PROTECTED] wrote: nice to see a wholesale DNSSEC rollout underway (I must confess to being a little surprised at the source, too!). Granted, it's a much more manageable problem set than, say, .com - but if one US-controlled TLD can do it, hope is buoyed for a .com rollout sooner rather than later (although probably not much sooner :)). I'm not much up on DNSSEC, but don't you need to be using a resolver that recognizes DNSSEC in order for this to be useful? /sf -- Jason 'XenoPhage' Frisvold [EMAIL PROTECTED] http://blog.godshell.com yes and no. to fully trust the data from the servers you need three things: ) signed data (this is what .gov is doing) ) a validator in the end system (this is mostly missing/not configured today) ) accurate trust anchors from a couple of places in the DNS namespace ## however, if all you start with is signed data - it becomes possible to verify the source of the data - independently of inline DNS validation. e.g. you can - with a high degree of certainty, be assured that the root zone you load is really the ORSN root and not that flaky root from DoC/ICANN/VSGN... :) so naked signed data, in the absence of TA's or validators is still useful. ## you'll need a couple of these - and how you get them and keep them up to date is still a mostly unsolved operational problem. --bill
Re: hat tip to .gov hostmasters
* marcus sachs: While we wait for applications to become DNSSEC-aware, Uhm, applications shouldn't be DNSSEC-aware. Down that road lies madness. What should an end user do when the browser tells him, Warning: Could not validate DNSSEC signature on www.example.com, signature has expired. Continue to connect? -- Florian Weimer[EMAIL PROTECTED] BFK edv-consulting GmbH http://www.bfk.de/ Kriegsstraße 100 tel: +49-721-96201-1 D-76133 Karlsruhe fax: +49-721-96201-99
Re: hat tip to .gov hostmasters
On Mon, Sep 22, 2008 at 11:11:40AM -0400, Keith Medcalf wrote: Correct, you need a validating, security-aware stub resolver, or the ISP needs to validate the records for you. That would defeat the entire purpose of using DNSSEC. In order for DNSSEC to actually provide any improvement in security whatsoever, the ROOT ZONE (.) needs to be signed, and every delegation up the chain needs to be signed. And EVERY resolver (whether recursive or local on host) needs to understand and enforce DNSSEC. er, no. the root zone does not need to be signed and not every delegation. and only the resolvers in the path from auth servers to validators need to ensure that the DNSSEC data is retained. if the only TA I have is for .SE (configured in my validator) and my resolver passes the DNSSEC data unchanged it received from the .SE servers, then I can securely trust the (short) validation chain when I look up axfr.se. even though -nothing else- is signed. If even one delegation is unsigned or even one resolver does not enforce DNSSEC, then, from an actual security perspective, you will be far worse off than you are now. depends on your POV of course... Until such time as EVERY SINGLE DOMAIN including the root is signed and every single DNS Server and resolver (including the local host resolvers) understand and enforce DNSSEC you should realize that DNSSEC does nothing for you whatsoever except give the uneducated a false sense of security. I think you have unrealistic expectations. Time will tell. It is likely that IPv48 will be deployed long before DNSSEC is implemented. --bill
Re: hat tip to .gov hostmasters
On Mon, Sep 22, 2008 at 05:24:00PM +0200, Florian Weimer wrote: * marcus sachs: While we wait for applications to become DNSSEC-aware, Uhm, applications shouldn't be DNSSEC-aware. Down that road lies madness. What should an end user do when the browser tells him, Warning: Could not validate DNSSEC signature on www.example.com, signature has expired. Continue to connect? -- Florian Weimer[EMAIL PROTECTED] actually, I am really hoping that at least one API is standardized so that applications can use DNSSEC data. We never finished the discussion on fail/open fail/closed wrt DNSSEC. --bill
Re: hat tip to .gov hostmasters
Jason Frisvold wrote: On Mon, Sep 22, 2008 at 11:02 AM, Chris Owen [EMAIL PROTECTED] wrote: Chicken, meet egg. I think the point of the original post is that one end or the other has to start things. At least we have one US zone doing something on the server end of things. Oh, agreed, absolutely. And it's great to see. However, neither the slashdot blurb, nor the NetworkWorld article mention that without a valid resolver, there is no guarantee of security. Sure, they mention that vendors are rolling it out and that ISPs should be following suit, but no mention is made of the end-user's resolver at all... I dunno, a few very strategically placed validating resolvers could subject a huge amount of DNS traffic to a much higher bar were the senders so inclined to sign their zones. But I tend to view these kinds of things much more from an epidemiology point of view: you don't have to have 100% eradication to control an epidemic. Same thing pretty much goes with internet based attacks, IMO: when the barrier is set sufficiently high in one area, attackers don't spend their entire time trying to break that barrier, they find the next lowest barrier and move on. Mike
RE: hat tip to .gov hostmasters
nice to see a wholesale DNSSEC rollout underway (I must confess to being a little surprised at the source, too!). Granted, it's a much more manageable problem set than, say, .com - but if one US-controlled TLD can do it, hope is buoyed for a .com rollout sooner rather than later (although probably not much sooner :)). It ain't done yet. I don't speak for the hostmasters of .gov or any subdomain thereof. But I'll believe it when I see it. Remember, they've also mandated IPv6 support on all backbones. -- Jim Goltz [EMAIL PROTECTED] CIT/DCSS/HSB/ASIG 12/2216
RE: hat tip to .gov hostmasters
That would defeat the entire purpose of using DNSSEC. In order for DNSSEC to actually provide any improvement in security whatsoever, the ROOT ZONE (.) needs to be signed, and every delegation up the chain needs to be signed. And EVERY resolver (whether recursive or local on host) needs to understand and enforce DNSSEC. Either the resolver needs to enforce, or the host. It's not necessary to do both. It's also not strictly necessary that the root is signed, provided that there is some way to manage the trust anchors (either through software updates, like it is done for the browser CA list, or through regular DNS management at the ISP resolver). If even one delegation is unsigned or even one resolver does not enforce DNSSEC, then, from an actual security perspective, you will be far worse off than you are now. Why? If the local resolver does not perform DNSSEC validation, then I cannot validate that the response is correct. I certainly do not trust anyone else to verify that the information is correct and then, without any possible verification, simply believe that the third party did the validation. In fact, I have no way of knowing that the response even came from the ISP at all unless the client resolver supports DNSSEC. Just because YOU check the digital signature on an email and forward that email to me (either with or without the signature data), if I do not have the capability to verify the signature myself, I sure as hell am not going to trust your mere say-so that the signature is valid! If I cannot authenticate the data myself, then it is simply untrusted and untrustworthy -- exactly the same as it is now. The real problem is that the clueless (with a hidden self-aggrandizing and a primary motive of lining my pockets with other peoples money will convince the ignorant that it is more secure. Sort of like banning toothpaste from carry-on baggage impoves the security of air travel, when in fact it does nothing more than help the idiots in charge of promulgating such polies to rip off (rob) other people of their money by deliberate fraud and misrepresentation. Until such time as EVERY SINGLE DOMAIN including the root is signed and every single DNS Server and resolver (including the local host resolvers) understand and enforce DNSSEC you should realize that DNSSEC does nothing for you whatsoever except give the uneducated a false sense of security. DNSSEC is totally invisible to the end user. There won't be any browser icon that says it's okay to enter your PII here because the zone is DNSSEC-signed. It's purely an infrastructure measure, like physically securing your routers. The end-stage is secure only if at that stage you also set all DNS infrastructure to refuse to talk to any DNS client/server/resolver that DOES NOT validate and enforce DNSSEC. Up until that point in time, there is NO CHANGE in the security posture from what we have today with no DNSSEC whatsoever. To hold forth otherwise is to participate in deliberate fraud and misrepresentation of material facts.
Re: hat tip to .gov hostmasters
On Mon, Sep 22, 2008 at 8:49 AM, Keith Medcalf [EMAIL PROTECTED] wrote: If even one delegation is unsigned or even one resolver does not enforce DNSSEC, then, from an actual security perspective, you will be far worse off than you are now. Why? If the local resolver does not perform DNSSEC validation, then I cannot validate that the response is correct. I certainly do not trust anyone else to verify that the information is correct and then, without any possible verification, simply believe that the third party did the validation. In fact, I have no way of knowing that the response even came from the ISP at all unless the client resolver supports DNSSEC. Just because YOU check the digital signature on an email and forward that email to me (either with or without the signature data), if I do not have the capability to verify the signature myself, I sure as hell am not going to trust your mere say-so that the signature is valid! If I cannot authenticate the data myself, then it is simply untrusted and untrustworthy -- exactly the same as it is now. so I guess PGP web of trust is right out, then? (in the real world, we rarely get boolean values on security questions) -- [EMAIL PROTECTED],darkuncle.net} || 0x5537F527 http://darkuncle.net/pubkey.asc for public key
RE: hat tip to .gov hostmasters
Just because YOU check the digital signature on an email and forward that email to me (either with or without the signature data), if I do not have the capability to verify the signature myself, I sure as hell am not going to trust your mere say-so that the signature is valid! If I cannot authenticate the data myself, then it is simply untrusted and untrustworthy -- exactly the same as it is now. so I guess PGP web of trust is right out, then? You are confusing validating signature with validating the holder of the keying material and the authorization of the holder to deploy it to create a non-repudiable signature, which are two entirely different and completely unreleated things. (This is quite common by the way, so maybe you can be excused your confusion). If there is a piece of data X signed with a cryptographically generated signature, and *I* verify that indeed the signature is valid, then the signature is valid -- that is, I can say with 100% absolute certainty that specific bit of keying material was used to generate a signature on something and that I have another bit of keying material which validates that signature. I am assured with very high certainty that THE DATA WAS SIGNED BY THE POSSESSOR OF THE SECRET KEYING MATERIAL. Nothing more can be determined from the signature. You now want to confuse the issue by associating the keying material with a person or entity. That problem is entirely outside the purview of the exercize and completely irrelevant. (I certainly do not trust that any certificate issued by a so-called Certificate Authority (other than myself) was issued to the entity it is purported to be issued to, nor that the key is properly kept secret, nor anything else. The mathematical validity of the signature is beyond question. Associating that signature to anything other than a mere statement that this data was signed by the possessor of the secret key corresponding to the public key that I have is a personal judgement call.
Re: hat tip to .gov hostmasters
At 15:30 + 9/22/08, [EMAIL PROTECTED] wrote: data. We never finished the discussion on fail/open fail/closed wrt DNSSEC. And I'd bet a dollar we never will finish that discussion. -- -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- Edward Lewis+1-571-434-5468 NeuStar Never confuse activity with progress. Activity pays more.
Re: hat tip to .gov hostmasters
The end-stage is secure only if at that stage you also set all DNS infrastructure to refuse to talk to any DNS client/server/resolver that DOES NOT validate and enforce DNSSEC. Up until that point in time, there is NO CHANGE in the security posture from what we have today with no DNSSEC whatsoever. To hold forth otherwise is to participate in deliberate fraud and misrepresentation of material facts. so you are a fail/closed proponent. a fail/open approach would have failure of DNSSEC-based validation behave just like the DNS of today. The use of Trust Anchors and signed islands allow one to find golden threads of validated chains in the dns fabric ... e.g. incremental rollout vs flag day. --bill
Re: hat tip to .gov hostmasters
On Mon, Sep 22, 2008 at 12:06:57PM -0400, Edward Lewis wrote: At 15:30 + 9/22/08, [EMAIL PROTECTED] wrote: data. We never finished the discussion on fail/open fail/closed wrt DNSSEC. And I'd bet a dollar we never will finish that discussion. -- -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- Edward Lewis+1-571-434-5468 NeuStar Never confuse activity with progress. Activity pays more. taken. (never is a -very- long time) --bill
Re: hat tip to .gov hostmasters
On Mon, Sep 22, 2008 at 12:14:53PM -0400, Keith Medcalf wrote: If I cannot authenticate the data myself, then it is simply untrusted and untrustworthy -- exactly the same as it is now. so I guess PGP web of trust is right out, then? [elided] If there is a piece of data X signed with a cryptographically generated signature, and *I* verify that indeed the signature is valid, then the signature is valid -- that is, I can say with 100% absolute certainty that specific bit of keying material was used to generate a signature on something and that I have another bit of keying material which validates that signature. I am assured with very high certainty that THE DATA WAS SIGNED BY THE POSSESSOR OF THE SECRET KEYING MATERIAL. Nothing more can be determined from the signature. let me understand this ... your use of the pronoun I in these contexts is in reference to your corporal being i.e. meatspace and not a software application running on some computer. --bill
Re: hat tip to .gov hostmasters
Date: Mon, 22 Sep 2008 11:42:33 -0400 From: Goltz, Jim (NIH/CIT) [E] [EMAIL PROTECTED] nice to see a wholesale DNSSEC rollout underway (I must confess to being a little surprised at the source, too!). Granted, it's a much more manageable problem set than, say, .com - but if one US-controlled TLD can do it, hope is buoyed for a .com rollout sooner rather than later (although probably not much sooner :)). It ain't done yet. I don't speak for the hostmasters of .gov or any subdomain thereof. But I'll believe it when I see it. I am pretty sure that you will see it. Unlike things like the IPv6 requirement, there are no waivers available for this. '.gov' must be signed early next year and all zones delegated from the '.gov' GTLD must be signed in early 2010. I doubt that many will sign until '.gov' is signed, so you won't see much change for a few months. Now, if the DOC people responsible for root would just catch a clue, we could get that signed and have DNSSEC actually usable (except for Mr. Metcalf) in a significant part of the US network before I retire. Remember, they've also mandated IPv6 support on all backbones. Yes, and the goal, relatively insignificant that it was, was met. It was not a requirement that anyone actually use IPv6, only that the agency backbone networks be able to carry IPv6. In fact, the wording was such that doing proper routing was not even really needed. Our backbone has offered IPv6 as a production service since 2002, so it was a non-effort for us. Most other agency backbones were pretty trivial to make IPv6 capable. The problem is that only the backbone currently needs IPv6. No facility network or end host needs it, No network service needs it. No IPv6 packets, even routing updates, need to be delivered in any useful way. It was a pretty trivial goal and was met with very little effort. -- R. Kevin Oberman, Network Engineer Energy Sciences Network (ESnet) Ernest O. Lawrence Berkeley National Laboratory (Berkeley Lab) E-mail: [EMAIL PROTECTED] Phone: +1 510 486-8634 Key fingerprint:059B 2DDF 031C 9BA3 14A4 EADA 927D EBB3 987B 3751 pgp2Nyla9XDdl.pgp Description: PGP signature
Re: hat tip to .gov hostmasters
On Sep 22, 2008, at 7:56 AM, Florian Weimer wrote: I'm not much up on DNSSEC, but don't you need to be using a resolver that recognizes DNSSEC in order for this to be useful? Yes, and you also need the trust anchors for the zones you want to validate configured. Correct, you need a validating, security-aware stub resolver, or the ISP needs to validate the records for you. Slight clarification: you need a validating, security-aware resolver, whether that resolver is local (e.g., running on the same machine issuing the DNS queries) or remote (e.g., your ISP's resolver). Note that, for good or ill, you are trusting the operator of the resolver and the communication channel between the resolver and the application making the DNS requests. A validating, security-aware _stub_ resolver, typically linked into the program issuing the DNS requests and thus would be the ultimate in 'local', would have the ability to validate the response and supply feedback to the application with minimum vulnerability to MITM attacks. The downside is the added complexity of the code to the validation and to handle validation failures. Regards, -drc
Re: hat tip to .gov hostmasters
On Sep 22, 2008, at 8:11 AM, Keith Medcalf wrote: Correct, you need a validating, security-aware stub resolver, or the ISP needs to validate the records for you. That would defeat the entire purpose of using DNSSEC. In order for DNSSEC to actually provide any improvement in security whatsoever, the ROOT ZONE (.) needs to be signed, and every delegation up the chain needs to be signed. The root does not need to be signed to provide security improvement. If you have configured the (say) .SE trust anchor in your validating resolver, you greatly reduce the chances that any lookup for a name in .SE can be spoofed. The downside of not having the root signed is that you need to maintain multiple trust anchors. And EVERY resolver (whether recursive or local on host) needs to understand and enforce DNSSEC. I personally believe it is more-or-less safe to trust communications local to the machine. As such, running a validating resolver on your local host would suffice. Having a stub resolver also validate in this scenario would be overkill. If even one delegation is unsigned or even one resolver does not enforce DNSSEC, then, from an actual security perspective, you will be far worse off than you are now. In what way? I'm running a validating resolver on my laptop (using the signed root zone and trust anchor available from ns.iana.org so I only have to deal with one trust anchor). If someone tries to spoof a name in the root, .SE, .BG, .PR, .BR, .CZ, their efforts will fail. How is this worse off than before I configured my resolver? Until such time as EVERY SINGLE DOMAIN including the root is signed and every single DNS Server and resolver (including the local host resolvers) understand and enforce DNSSEC you should realize that DNSSEC does nothing for you whatsoever except give the uneducated a false sense of security. If this were true, DNSSEC would be a complete waste of time. Fortunately, it isn't true. Regards, -drc
Re: hat tip to .gov hostmasters
Kevin Oberman wrote: Date: Mon, 22 Sep 2008 11:42:33 -0400 From: Goltz, Jim (NIH/CIT) [E] [EMAIL PROTECTED] Remember, they've also mandated IPv6 support on all backbones. Yes, and the goal, relatively insignificant that it was, was met. It was not a requirement that anyone actually use IPv6, only that the agency backbone networks be able to carry IPv6. In fact, the wording was such that doing proper routing was not even really needed. Our backbone has offered IPv6 as a production service since 2002, so it was a non-effort for us. Most other agency backbones were pretty trivial to make IPv6 capable. The problem is that only the backbone currently needs IPv6. No facility network or end host needs it, No network service needs it. No IPv6 packets, even routing updates, need to be delivered in any useful way. It was a pretty trivial goal and was met with very little effort. They mandated that all products, not just hardware, support IPv6. However, all that the requirement turned out to be, in practice, is that all products be software upgradeable to IPv6. My employer is still selling stuff by the truckload to the USG because the hardware itself is IPv6 capable (just like it's OSI or DECnet capable), but we haven't written a single line of IPv6 code yet because customers aren't actually demanding it and we have other, more profitable, things to spend developers' limited time on. For vendors whose hardware needs to change for IPv4, like core routers, this is a big deal; for the rest of us, it was a non-event once we read the fine print. S
RE: hat tip to .gov hostmasters
Subject: RE: hat tip to .gov hostmasters Date: Mon, 22 Sep 2008 11:49:50 -0400 From: Keith Medcalf [EMAIL PROTECTED] If I cannot authenticate the data myself, then it is simply untrusted and u= ntrustworthy -- exactly the same as it is now. Speak for yourself, John applies. In the real world, there are cases where data that one is unable to authenticate by ones self *is* treated as fully trusted. Because someone with the authority to declare it to be that, by fiat, has done so. There may be a common chain of command, and someone higher in the chain has declared that various inferiors shall(i.e. 'must') trust the work of other inferiors within the organization, for example. Or, it may be a contractually-delegated trust. Or, any of a number of other possibilities. Admittedly, in any of those scenarios, the 'strength' of trust is somewhat weaker than if it was self-verified, but it _is_ far above your claim of 'untrusted and untrustworthy'. The end-stage is secure only if at that stage you also set all DNS infrastr= ucture to refuse to talk to any DNS client/server/resolver that DOES NOT va= lidate and enforce DNSSEC. Up until that point in time, there is NO CHANGE= in the security posture from what we have today with no DNSSEC whatsoever. FALSE TO FACT. One does not have a _guarantee_ of 'accurate' data without end-to-end enforcement, this is true. Even _with_ end-to-end DNSSEC enforcement, one does not have such a guarantee. All it accomplishes is to make the insertion of bogus data harder. Not 'impossible', just 'harder'. If a local non-DNSSEC resolver consults _only_ a DNSSEC-aware server on an immediately adjacent network, it takes only a moderate 'extension of trust' to (a) the local network operator, (b) the adjacent network operator, and (c) the DNSSEC-aware server operator, to have a reasonable degree of trust in the accuracy of the data the local reslover has. This 'trust' involves the physical integrity of the networks -- that a host on -those- networks will not be allowed to spoof a source address of the DNSSEC-aware server; and the use of ingress-filtering on _source_ addresses -- to prevent any 'external' network/machine from spoofing it either. Beyond that, it is just a matter of 'trusting' a proper implementation on the server itself. _IF_ the anti-spoofing provisions are in place, and 'downstream' (non-aware) DNS resolvers (which consult -only- the 'aware' server) are under the same administrative control as the DNSSEC-aware one, *THEN* there is zero effective difference in the trust level for an answer obtained from the 'non-aware' system as one obtained from the 'aware' one. To hold forth otherwise is to participate in deliberate fraud and misrepres= entation of material facts. This really sounds like someone who has a financial interest in promulgating FUD. grin
RE: hat tip to .gov hostmasters
To digress on IPv6 momentarily.
The airline magazine engineering memorandum* from OMB left two terms
undefined in the mandate; backbone network and IPv6 compatible. The
Intra-agency IPv6 Federal Working Group wisely defined backbone
network as (paraphrasing) the wire exiting the first publicly-reachable
network perimeter router and entering the router next in the line of
traffic and all devices attached to that wire between those two points
as follows:
{Internet}-|router|-connecting wire---IPV6-[firewall, IDS,
etc.]-IPV6--connecting wire-|next router in line|-NO IPV6-...
NIST is still working on compatible.
*Airline Magazine Engineering Memorandum: a mandate issued by an
executive who can. The memorandum has four characteristics; 1) It
mandates a technology not well understood by either the issuer or the
recipient of the memo, 2) it sets a date certain by which the technology
must be implemented, 3) it provides no funding, and 4, it contains one
or more undefined terms whose exact meanings are absolutely crucial to
actual implementation of the mandate. Source of the inspiration that
originally convinced the issuing executive that they actually understood
the scope and technology of the mandate is inherent in the title of this
paragraph.
JimL
James R Lindley
Senior Computer Engineer
Advanced Technical Analysis Team
IT Security Architecture and Engineering
Internal Revenue Service
An unquenchable thirst for Pierian waters.
-Original Message-
From: Kevin Oberman [mailto:[EMAIL PROTECTED]
Sent: Monday, September 22, 2008 12:54
To: Goltz, Jim (NIH/CIT) [E]
Cc: nanog@nanog.org
Subject: Re: hat tip to .gov hostmasters
Date: Mon, 22 Sep 2008 11:42:33 -0400
From: Goltz, Jim (NIH/CIT) [E] [EMAIL PROTECTED]
nice to see a wholesale DNSSEC rollout underway (I must confess to
being a little surprised at the source, too!). Granted, it's a much
more manageable problem set than, say, .com - but if one
US-controlled TLD can do it, hope is buoyed for a .com rollout
sooner rather than later (although probably not much sooner :)).
It ain't done yet.
I don't speak for the hostmasters of .gov or any subdomain thereof.
But I'll believe it when I see it.
I am pretty sure that you will see it. Unlike things like the IPv6
requirement, there are no waivers available for this. '.gov' must be
signed early next year and all zones delegated from the '.gov' GTLD must
be signed in early 2010. I doubt that many will sign until '.gov' is
signed, so you won't see much change for a few months.
Now, if the DOC people responsible for root would just catch a clue, we
could get that signed and have DNSSEC actually usable (except for Mr.
Metcalf) in a significant part of the US network before I retire.
Remember, they've also mandated IPv6 support on all backbones.
Yes, and the goal, relatively insignificant that it was, was met. It was
not a requirement that anyone actually use IPv6, only that the agency
backbone networks be able to carry IPv6. In fact, the wording was such
that doing proper routing was not even really needed.
Our backbone has offered IPv6 as a production service since 2002, so it
was a non-effort for us. Most other agency backbones were pretty trivial
to make IPv6 capable.
The problem is that only the backbone currently needs IPv6. No facility
network or end host needs it, No network service needs it. No IPv6
packets, even routing updates, need to be delivered in any useful way.
It was a pretty trivial goal and was met with very little effort.
--
R. Kevin Oberman, Network Engineer
Energy Sciences Network (ESnet)
Ernest O. Lawrence Berkeley National Laboratory (Berkeley Lab)
E-mail: [EMAIL PROTECTED] Phone: +1 510 486-8634
Key fingerprint:059B 2DDF 031C 9BA3 14A4 EADA 927D EBB3 987B 3751
Re: hat tip to .gov hostmasters
In article [EMAIL PROTECTED] you write: * marcus sachs: While we wait for applications to become DNSSEC-aware, Uhm, applications shouldn't be DNSSEC-aware. Down that road lies madness. What should an end user do when the browser tells him, Warning: Could not validate DNSSEC signature on www.example.com, signature has expired. Continue to connect? The application just rejects the answer. Trys again a couple of times then reports failure. This is no different to the application talking to the validating resolver a couple of time and then reporting failure. The advantage of having the application do it is that you don't need to secure the connection between the validating resolver and the application. Mark
