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Mac OS X Problem Puts Up a Block To IPv6
An anonymous reader lets us know of an experiment conducted in Norway to determine real-world problems in using IPv6 today (Google translation; Norwegian original). "According to a Norwegian article in digi.no, Redpill Linpro did an experiment with regard to IPv6 on one of the largest online newspapers there (www.vg.no). They added a hidden iframe that pointed to an IPv6-enabled domain to test real-life problems about the reported IPv6 holes. The result was that mainly Mac OS X, older versions of Opera, and a few Linux distributions exhibited problems. For Mac OS X it took 75 seconds to time out before failing back to IPv4." From the consultant's report: "Mac OS X has a problem in that it will prefer 6to4-based IPv6 over IPv4-based connectivity, at least if its local IPv4 address is an RFC 1918-based private address as commonly found in NAT-ed home network environments. This is unfortunate, as 6to4 has shown itself to be much less reliable than IPv4."
Apple is now hated slightly less than MS, which is pretty significant given how maybe a decade ago they were not hated at all. That's what happens when you become a corporate behemoth.
They weren't hated, they were held in contempt for making closed boxes that no one wanted to buy. What truly enrages the ilk of slashdot is that over the past ten years is that Apple has made a killing selling closed boxes, when all of the "common sense" of open source evangelism told them this was unpossible.
Don't blame me, I voted for Baltar.
No, it wasn't. It was a large re-architecting of a lot of subsystems. This does not mean a lot for most users, thus they only announced a couple of user-visiable feautres. Not the same thing at all.
For developers Snow Leopard was a rather feature-rich update.
Almost certainly the latter.
The article, and the accompanying 'raw' data, are not sufficiently detailed to draw the conclusion that OS X is at fault. The observation is that browsers with Mac OS X in the User-Agent string are more commonly using 6to4 addresses. The faulty assumption is that Mac OS X prefers 6to4 addresses to RFC1918 addresses.
The reality is that getaddrinfo() on several platforms prefers IPv6 addresses over IPv4, if the host OS has an active IPv6 service. This is not unique to OS X, nor is it a bug.
The interesting part is that the only CPE devices which support IPv6 are Apple Airports - the Extreme and Express models. They use 6to4 if there is no native IPv6 address provided. No ADSL modems available to consumers support IPv6 out of the box, ergo, almost every Airport user has 6to4 enabled. If one assumes that most Airport users are also Mac users, then the observation that excluding Mac OS X User-Agents from the result set also excludes the bulk of IPv6 users is not surprising.
If Apple has an issue, it's that they enable 6to4 by default on a consumer device, when 6to4 is a known-bad mechanism that should be avoided.
If one is running dual stack services, one should be aware of the most common pitfalls: see http://www.potaroo.net/ispcol/2010-05/v6hints.html for details.
How is their a difference? if Mac did not properly support IPv6 then it is their problem.
I'm not sure quite what he meant by "properly supported in the wild" but it sounded like he was trying to point out that sometimes you do get bugs because you implement things correctly but somebody else screwed up their implementation. A while back I had a problem connecting Linux and OS X based VPN daemons to some Microsoft VPN servers. At first it seemed obvious that this was Apple screwing up. After some considerable wiresharking and digging in Apple's source code I found out that Microsoft's VPN server sends malformed protocol messages which the Linux/OS X based counterparts try to parse according to the letter of the specification and exit with an error when they run into problems. Not that I'm trying to absolve Apple of all blame they can fuck up like everybody else and do so regularly, however that doesn't change the fact that it's entirely possible to render your software unusable by implementing it according to specifications. In a situation like that you can either change your software to take the buggy implementation by <insert name of manufacturer> into account or stick to your guns and piss off your users.
Only to idiots, are orders laws.
-- Henning von Tresckow