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Theo De Raadt's Small Rant On OpenSSL
New submitter raides (881987) writes "Theo De Raadt has been on a better roll as of late. Since his rant about FreeBSD playing catch up, he has something to say about OpenSSL. It is worth the 5 second read because it is how a few thousand of us feel about the whole thing and the stupidity that caused this panic."
Update: 04/10 15:20 GMT by U L : Reader badger.foo pointed out Ted Unangst (the Ted in the mailing list post) wrote two posts on the issue: "heartbleed vs malloc.conf and "analysis of openssl freelist reuse" for those seeking more detail.
Theo De Raadt is a noteworthy personality, same as Linus Torvalds or Bill Gates. Their comments on important matters are important.
If your intermediate certificate's signing keys are on the internet facing web servers you're doing it wrong. That intermediate signing key should be treated with the same level of security you would treat a root key with.
As much as Theo can be an utter and insufferable prick, on this score he's right. This was an insanely trivial error which has exposed who knows how many systems to potential breaches. Right now I'm starting up a full audit of our systems. We use OpenVPN for our interoffice WAN, as well as for clients; many of them Windows, iOS and Android clients, not to mention reviewing all our *nix clients running SSH daemons. We're only a relatively small operation, and it's still a monumental pain in the ass.
The world's burning. Moped Jesus spotted on I50. Details at 11.
That's all true and correct. When you do that, though, you need to do at least as good a job as what you're circumventing. In this case OpenSSL didn't.
My understanding is Theo said: Developers on a security product made a conscious decision to turn off last line of defence security for all platforms in the interest of performance on some systems. That does not sound like and unfortunate error to me, it sounds outright irresponsible.
Theo's point isn't that OpenBSD users would have been safe. It's that had OpenSSL crashed on OpenBSD (or any OS with similar mitigation in place) it would have surfaced the bug much sooner...perhaps before a worldwide release. Once found it would have been fixed and merged upstream to benefit all users.
This is really a specific case of the larger point behind avoiding monoculture, whether OS or hardware. OpenBSD continues to support older architectures in part because it forces them to work through issues that benefit other platforms, especially the one most of us use daily: x86.
In addition, the mitigation countermeasures also prevent memory debuggers like Valgrind from finding the problem (Valgrind find use-before-init for malloc'ed blocks, but not if there is a wrapper in between that re-uses blocks), and may also neutralize code-security scanners like Fortify.
I have to admit that while my original intuition was "screwup", this looks more and more like some parts of the OpenSSL team have been compromised and did things that make this kind of bug far more likely. Like their own insecure memory allocation. Like not requiring time-of-use boundary checks or having any secure coding guidelines in the first place. Like documenting everything badly so potential reviewers get turned away. Like not having working review for patched or a working fuzz-testing set-up (which would have found bug this easily).
After all, the NSA does not have to sabotage FOSS crypto software. They just have to make sure the quality is low enough. The bugs they can exploit will follow. And the current mess is just a plain classic. Do enough things wrong and eventually stuff breaks spectacularly.
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.
Well, what you are pointing out is that a CA is a single point of failure -- Something actual security conscious engineers avoid like the plague. What you may not realize is that collectively the entire CA system is compromised by ANY ONE of those single points of failure because any CA can create a cert for ANY domain without the domain owner's permission. See also: The Diginotar Debacle.
The thing is, nobody actually checks the the cert chain, AND there's really no way to do so. How do I know if my email provider switched from Verisign to DigiCert? I don't, and there's no way to find out that's not susceptible to the same MITM attack.
So, let's take a step back for a second. Symmetric stream ciphers need a key. If you have a password as the key then you need to transmit that key back and forth without anyone knowing what it is. You have to transmit the secret, and that's where Public Key Crypto comes in, however it doesn't authenticate the identity of the endpoints, that's what the CA system is supposed to do. Don't you see? All this CA PKI system is just moving the problem of sharing a secret from being the password, to being which cert the endpoint is using -- That becomes the essential "secret" you need to know, and it's far less entropy than a passphrase!
At this time I would like to point out that if we ONLY used public key crypto between an client and server to establish a shared secret upon account creation, then we could use a minor tweak to the existing HTTP Auth Hashed Message Authentication Code (HMAC) proof of knowledge protocol (whereby one endpoint provides a nonce, then the nonce is HMAC'd with the passphrase and the unique-per-session resultant hash provides proof that the endpoints know the same secret without revealing it) to secure all the connections quite simply: Server and client exchange Nonces & available protocols for negotiation, the nonces are concatenated and HMAC'd with the shared secret stored at both ends, then fed to your key-stretching / key expansion system AND THAT KEYS THE SYMMETRIC STREAM CIPHER SIMULTANEOUSLY AT BOTH ENDS so the connection proceeds immediately with the efficient symmetric encryption without any PKI CA system required.
PKI doesn't really authenticate the endpoint, it just obfuscates the fact that it doesn't by going through the motions and pretending to do so. It's a security theater. SSL/TLS and PKI are essentially the Emperor's New Secure Clothes. At least with the shared secret model I mention above, there's just that one-time small window of PK crypto for secret exchange at worst (failing to intercept account creation means no MITM) and at best you would actually have the CHANCE to go exchange your secret key out of band -- Visit your bank in person and exchange the passphrase, etc. then NO MITM could intercept the data. HTTP Auth asks for the password in a native browser dialog BEFORE showing you any page to login (and it could remember the PW in a list, or even generate them via hashing the domain name with a master PW and some salt so you could have one password for the entire Internet). That's how ALL security should work, it ALL relies on a shared secret, so you want the MOST entropic keyspace not the least entropic selection (which CA did they use). If you're typing a password into a form field on a web page, it's ALREADY game over.
Do this: Check the root certs in your browser. For Firefox > Preferences > Advanced > Certificates > View. See that CNNIC one? What about the Hong Kong Post? Those are Known bad actors that your country is probably at cyber war with, and THEY ARE TRUSTED ROOTS IN YOUR FUCKING BROWSER?! Not to mention all the other Russian ones or Turkish, etc. ones that are on the USA's official "enemy" list. Now, ANY of those can pretend to be whatever domain's CA they want, and if your traffic bounces through their neck of the woods they can MITM you and you'll be n
but if your explicit reason for overriding the kernel is to do something as-good-or-better than the kernel, and you fail to achieve that (let alone validate that you've achieved it), that's a rather spectacular failure. mistakes are common, sure. but this is sort of like saying the seatbelts that came with your car suck (they very well might), so you replace them with something "better", that ends up being little more than a piece of string that you daintily lay across your lap. kind of "unreasonable", no...?