Root-server switches from BIND to NSD

A Sorry End writes "It appears that one of the 13 root-servers, the core of DNS name resolution, have moved away from BIND to NSD since wednesday, Feb 19th, 2003, which is a Good Thing. Since the 26th of october 1990, all root-servers have been running BIND. According to this message, this change was designed to increase the diversity of software in the root name server system, the lack of which is widely considered to be a potential vulnerability. The nsd software has been designed from scratch specifically as an authoritative name server. It has no design commonalities with bind, the currently prevalent DNS implementation. In addition to that nsd provides a significant increase in the performance reserve of k.root-servers.net. NSD was developed at NLnet Labs in coorperation with RIPE."

Comments

Just like biological ecosystems

[hpulley]

Having no diversity means you are ripe for an epidemic.

Diying?

[ricbasto]

I don't think the plan is to migrate away from BIND, but instead to protect the root-servers from a bind-specific exploit.
There will be years for BIND to loose it's marketshare.

Specs on BIND Vs NSD

[phorm]

If a lot of /.'ers are like me, then there are probably a lot of people who don't know the technical differences between BIND and NSD. Can somebody whack us with the proverbial cluestick as to the improvements of NSD over BIND (exempting of course, the mentioned fact that NSD was built from scratch).

I wonder what anomalies, if any, we may see from switching over. Also, as the article mentions that NSD has no design commonalities with BIND, I wonder how many of the tech personnel are knowledgable on the new system...not that a nameserver, even a root one, should be overtly complicated (except for evading DOS attacks)

Same interface, different implementation

[$$$$$exyGal]

It has no design commonalities with bind...

This is great, but I wanted to point out that the new software does have design commonalities with bind. The way I see it, they both support the same external interface, but they have different implementations.

--sex

Re:New vulnerabilities

[cduffy]

The argument isn't specific to NSD, but rather general to all cases where a wider array of software is deployed to avoid a monoculture for security reasons: In places where previously BIND needed to be compromised to affect an attack, now either BIND *or* NSD may be compromised. That's not to say that such an attack is necessarily easy with NSD, or that it has known vulnerabilities -- simply that *if* a vulnerability is discovered in one of *two* packages, this can be translated into such a larger attack (rather than having only a single point of vulnerability).

Running a wider array of software on the root nameservers is still almost certainly a Good Thing , and decreases the probability than all of the servers will be prone to any given vulnerability -- but also increases the probability that a vulnerability will be found such that some subset of the servers is prone.

Re:So how secure is it?

[johnnyb]

Diversifying for the sake of diversifying is still useful. If person A finds a flaw in one of the two systems, the rest are still functioning. This requires an attacker to have exploits for all systems, not just one. The diversity itself is a barrier.

Diversity is good

[MojoRilla]

Competition is a good thing. See Intel vs. AMD, Sony vs. Nintendo, Linux vs. Microsoft.

For very high reliability software, competition is also used. For example, the space shuttle uses four sets of identical software on four sets of hardware that vote on results, with a fifth set running completely different software waiting to take over if the other fail (see Fastcompany for more details).

Also, one of the benefits of breaking up Ma Bell was that one company, with one set of software, was no longer running the telephone system in the United States.

In the long run I think this is a very good thing. In the short run, however, there might be problems.

Re:they should use djbdns

[bourne]

Oh wait. NONE OF THAT IS TRUE. Never mind.

You're absolutely right. djbdns doesn't have anything going for it except exceptional security and performance, and why would a root name server need that?

Waste of effort

[iamacat]

One bad thing is that NSD is only for authoratitive name servers, so the efforts spent developing, debugging, porting and optimizing its code will be wasted for most of us. More people using NSD would also mean that any security exploits are discovered faster and on less important systems than root name servers. And couldn't we all use a lightweight, secure, chaching name server to use over a dialup connection?

I would rather see them pick some alternative general purpose DNS implementation and optimize it for their needs.

Re:Open Source

[babbage]

Running diverse software on the roots is probably a Good Thing, but security through obscurity isn't

Man this is such a false meme, where did it get started? Obscurity by itself is questionable security, but as a component of a multi-layered security strategy it's perfectly reasonable.

• Security by obscurity is your world-readable /etc/passwd file, with the password data either hashed (obscured) or moved to the shadow file (also obscured). (And if your shadow password file isn't world readable, that's just more obscurity.)

• Security by obscurity is the fact that most people don't have the names & addresses of the personnel running the US military's nuclear weapons systems so that these people can't be blackmailed. Maybe these people can be trusted not to betray their country under torture and such, but keeping their identities non-public -- an obscurity measure -- is important too.

• Security by obscurity is Dick Cheney's "undisclosed location" (*cough* Greenbrier Resort, White Sulphur Springs, West Virginia)

• Security by obscurity is restricting access to your company's co-location facility, so that untrusted people can't get physical access to your equipment.

In short, in a broad sense, "security by obscurity" is a lot of good ideas, when you think about it. Any of these ideas can be an Achilles heel, but the solution there is not to cut off the heel altogether, but to wear sensible shoes when going out in the wilderness :)

To get back to the original topic, obscurity is a perfectly good tactic for the people running these DNS servers as part of their overall strategy for protecting the system. It's perfectly reasonable for certain aspects of their systems, processes, etc to be kept on a need to know basis. Sure, there is a benefit to keeping software source open as a security measure, though the benefit of doing that is debatable (and no, I'm not going to be the one to debate it -- I agree that it's generally a good idea but can understand some of the objections). But in this case, where the software is a black box to the outside world, and it's explicitly *not* meant for general DNS use (it's meant for authoritative servers only!) I don't see any particular harm in keeping their doors locked down pretty well.

Not that they're doing that in the first place. As another reply noted, you yourself write that both the betas & release will be available under a BSD style license :-)

But moreover, your objections are I think misplaced -- as are most of the people that blindly parrot the "obscurity is bad" meme. Think about what you're saying -- it really doesn't hold up to scrutiny.

Re:So how secure is it?

[caluml]

Well, I can only speak from personal experience, ratheer than just listening to people who say it's insecure.

I've never had any security problems with it. Chrooted, and running as a non root user helps. Funny how once something gets a reputation, it never seems to be able to shake it off.