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Single random bit flip causes error in certificate transparency log

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Re: Single random bit flip causes error in certificate transparency log

#141
post #125
post #119

Earlier quoted context omitted.

Distributed, byzantine fault tolerant state machines solve that. At worst, a single node will go out of sync.

This is a great way to say "blockchain" without getting guaranteed down votes ;)

You made me smile, however:

I'm one of those who can easily downvote blockchain stuff mercilessly. It is not reflexively though: I reserve it for dumb ideas, it just so happens that most blockchain ideas I see come off as dumb and/or as an attempted rip off.

Re: Single random bit flip causes error in certificate transparency log

#142
post #108

Why can't this be fixed? Merkle trees are just linked hashes that depend on the previous results, right? so why can't they just continue from the last correct hash?

Because that would violate the append-only property that CT logs are required to abide by.

Re: Single random bit flip causes error in certificate transparency log

#143
post #136
post #124

Earlier quoted context omitted.

This is just learned helplessness because Intel were stingy as shit for over a decade and wanted to segregate their product lines. Error correction is literally prevalent in every single part of every PHY layer in a modern stack, it is an absolute must, and the lack of error correction in RAM is, without question, a ridiculous gap that should have never been allowed in the first place in any modern machine, especiall…

'stingy as shit' or maximising short-term shareholder value -- the hardware is possibly not the only broken model here

You're probably right that I'm giving them a bit too much credit on that note. Ceterum censeo, and so on.

Re: Single random bit flip causes error in certificate transparency log

#144
post #125
post #119

Earlier quoted context omitted.

Distributed, byzantine fault tolerant state machines solve that. At worst, a single node will go out of sync.

This is a great way to say "blockchain" without getting guaranteed down votes ;)

Yes, and also contrary to Wikipedia it provides a solid use case for private blockchain https://en.wikipedia.org/wiki/Blockchain#Disadvantages_of_pr...

I think it is instructive to ask "why doesn't this mention guarantee downvotes?" because I don't think it's just cargo-culting. I doubt that many of those objecting to blockchain are objecting to byzantine fault tolerance, DHT, etc. Very high resource usage in the cost function, the ledger being public and permanent (long term privacy risk), negative externalities related to its use in a currency... These are commonly the objections I have and hear. And they are inapplicable.

Extending what the Wikipedia article says, it's basically glorified database replication. But it also replicates and verifies the calculation to get to that data so it provides far greater fault tolerance. But since it is private you get to throw out the adversarial model (mostly the cost function) and assume failures are accidental, not malicious. It makes the problem simpler and lowers the stakes versus using blockchain for a global trustless digital currency so I don't think we should be surprised that it engenders less controversy.

Re: Single random bit flip causes error in certificate transparency log

#145
post #119
post #65

The push for crypto without ecc ram is a nonstop horror show. Software under normal circumstances is remarkably resilient to having its memory corrupted. However crypto algorithms are designed so that a single bit flip effectively changes all the bits in a block. If you chain blocks then a single bit flip in one block destroys all the blocks. I've seen companies like msps go out of business because they were doing cr…

Distributed, byzantine fault tolerant state machines solve that. At worst, a single node will go out of sync.

[deleted]

Re: Single random bit flip causes error in certificate transparency log

#146
post #24

Earlier quoted context omitted.

"cosmic rays" are more of a well-known term of art for "single bit flipped with unknown hardware cause" than a reference to literal cosmic rays

I remember an older less-computer savvy gentlemen asking for support because "the program isn't working", when after a few questions we realized his computer won't boot up (screen dark, etc.). We thought his terminology was all screwed up. But now I realize he just lacked the necessary PR skill. He should have said that "the program isn't working" is a well-known term of art for power users such as himself. The fact…

> If you go an appropriate it to describe a whole bunch of phenomena because you can't be bothered to distinguish between them

Cosmic ray is the appropriate colloquial term. Just like "bug" is the appropriate term to describe computer problems that have nothing to do with insects. It's a well established colloquialism and not simply terminology made up on the spot like in your example.

Re: Single random bit flip causes error in certificate transparency log

#147
post #129

Earlier quoted context omitted.

It doesn't break anything that I can see (though I'm no expert on the particular protocol). Our ability to detect bad certs isn't compromised, precisely because this was noticed by human beings who can adjust the process going forward to work around this. Really the bigger news here seems to be a software bug: the CT protocol wasn't tolerant of bad input data and was trusting actors that clearly can't be trusted full…

Your statement is, to be frank, non-sensical. The protocol itself isn't broken, at least for previous Yeti instances, certificate data are correctly parsed and rejected.* In this instance, it seems that the data is verified already pre-signing BUT was flipped mid-signing. This isn't the fault of how CT was designed but rather a hardware failure that requires correction there. (Or at least that's the likely explanatio…

So I'm learning about Yeti for the first time, but I don't buy that argument. Corrupt tranmitted data has been a known failure mode for all digital systems since they were invented. If your file download in 1982 produced a corrupt binary that wiped your floppy drive, the response would have been "Why didn't you use a checksumming protocol?" and not "The hardware should have handled it".

If Yeti can't handle corrupt data and falls down like this, Yeti seems pretty broken to me.

Re: Single random bit flip causes error in certificate transparency log

#148
post #123
post #110

Earlier quoted context omitted.

> The push for crypto without ecc ram is a nonstop horror show That's a bit hyperbolic. First, ECC doesn't protect the full data chain, you can have a bitflip in a hardware flip flop (or latch open a gate that drains a line, etc...) before the value reaches the memory. Logic is known to glitch too. Second: ECC is mostly designed to protect long term storage in DRAM. Recognize that a cert like this is a very short-ter…

If a system is critical it should run on multiple machines in multiple locations and "sync with checks" kinda like the oh so hated and totally useless blockchains. Then if such a bit-flip would occur it would never occur on all machines at the same time in the same data. And on top of that you could easy make the system fix itself if something like that happens (simply assume the majority of nodes didn't have the bit…

Safety critical systems are not a good fit for a blockchain-based resolution to the Byzantine General problem. Safety critical systems need extremely low latency to resolve the conflict fast. So blockchain is not going to be an appropriate choice for all critical applications when there are multiple low-latency solutions for BFT at a very low ms latency and IIRC, microseconds for avionics systems.

Re: Single random bit flip causes error in certificate transparency log

#149
A few years ago there was a CCC? talk about registering domains a bitflip away from the intended domain. Which effectively hijacked legitimate web traffic. While the chance of a bitflip is low it added up to a surprisingly large number of requests maybe a few hundred or so. Here is someone doing it for windows.com https://www.bleepingcomputer.com/news/security/hijacking-tra...

Re: Single random bit flip causes error in certificate transparency log

#150
post #63

Do nuclear missiles have this anywhere? bool launch = false; if(launch) ...

There have been false alerts caused by single chip failures. 1980 there was nuclear alert in the US that lasted over three minutes. Generally critical systems can't be armed without physical interaction from humans. It's not just computer logic, but powering up the system that can do the launch. It does not matter what the logic does as long as ignition system is not powered up using physical switch.

I watched this documentary when young, the computer thought it was all a game?
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