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▲ fidotron 3 hours ago

While this confirms the method of production it doesn't say anything about their selection, especially since they were, apparently, generated over a period of months. Specifically you cannot see those candidates that were generated and discarded.

"It is still conceivable that these curves were selected to have a specific property in principle by searching over timestamps to the random number generator."

Yes.

"However, you would only need to do that if you were going to disclose the timestamp as some evidence that the seed was innocuously generated."

Does not logically follow when "doing and saying nothing" will completely suffice.

▲FiloSottile 4 minutes ago | parent | next [-]

Given how expensive this computation would have been in 1997, it makes perfect sense they'd taken months, but even if we assume they tried all timestamps of 1997 and selected arbitrarily among the first 16 viable candidate for each timestamp, that's just ~30 bits of freedom.

Finding out there is a class of weak 256-bit elliptic curves so large that they can be hit randomly with 2^30 tries would be a cryptanalytic breakthrough analogous to discovering all elliptic curve cryptography is broken.

Read section 3.1 of the Koblitz and Menezes paper. It was already implausible with 160 bits of freedom. https://eprint.iacr.org/2015/1018

If you want to believe the NSA knows ECC is broken and chose to risk moving the US government to it and somehow no one figured out the same break in 30 years, you're free to do so. But pretending the seed choice plays any role in that theory is over.

▲connorboyle 7 minutes ago | parent | prev | next [-]

I think it does rule out any NOBUS vulnerability with these curves, doesn't it? My thinking may be a bit sloppy here, but for a curve to be NOBUS exploitable with N-bit security by its creators, I think it would have to have a property only shared by 1/(2^N) curves. It would be impractical to hash 2^(N-1) timestamps until you find one with the desired property, for any decent size of N--which is how many you'd have to do on average before finding one with that property.

▲defen an hour ago | parent | prev | next [-]

> While this confirms the method of production it doesn't say anything about their selection, especially since they were, apparently, generated over a period of months. Specifically you cannot see those candidates that were generated and discarded.

Well, at least now we have a way to perform that analysis! Generate a bunch of curves by varying (along any degree of freedom) the input parameters to the seed generating function and see if there's any difference between the curves that are generated.

▲tptacek 3 hours ago | parent | prev | next [-]

God bless you for keeping this alive.

▲fidotron 3 hours ago | parent [-]

It doesn't prove anything about the core part of the suspicion, which is they were selected using some undisclosed criteria, which may make them weaker or stronger than some other random numbers.

You are entirely familiar with the precedent of the DES s boxes of course, where that is exactly what happened.

▲JumpCrisscross 3 hours ago | parent [-]

> which may make them weaker or stronger than some other random numbers

Are there non-trivial weaker and stronger seeds for this category of elliptic curves?

▲fidotron 3 hours ago | parent [-]

Exactly.

When they made the changes to the s boxes for differential cryptanalysis resistance the entire concept of that was essentially secret, so who knows what they know about elliptic curves.

▲matthewdgreen 2 hours ago | parent | next [-]

The number of weak classes of elliptic curve would have to be gargantuan for this specific search to produce some. If that many curves are bad, then ECC was a mistake.

▲1sha an hour ago | parent | next [-]

drand48() could be one of hundreds of methods that were tried to produce specific values with plausible deniability and happened to produce them. The other searches were discarded.

▲fidotron an hour ago | parent | prev [-]

Then why not turn this around and say which (hopefully small set of) specific classes of curves are known to be avoided, but otherwise have a free for all?

> If that many curves are bad, then ECC was a mistake.

I mean that is the logical conclusion from the behaviour around this approach where a few good things are effectively endorsed without justification.

The fact is any application of an algorithm that involves so much "trust me bro" on the selection of what are a large number of opaque quasi random but not quite or provably so numbers only has as much trust in it as you have in the people that created it.

▲tptacek 2 hours ago | parent | prev [-]

Again, Koblitz and Menezes take this idea on directly in their paper. But I mean, at this point, nobody serious is going to take the P-curve seed conspiracy theory seriously ever again.

▲bflesch 2 hours ago | parent | prev | next [-]

If you keep posting like this you're gonna get microwaved from space ;)

▲fidotron an hour ago | parent [-]

I'm only posting like this because they already are.

▲bflesch 25 minutes ago | parent [-]

Check out 133784883 then, it really gets the machine going.

▲cookiengineer a few seconds ago | parent [-]

> 133784883

Ghislaine Maxwell's social security number?

▲1230917 2 hours ago | parent | prev [-]

"However, you would only need to do that if you were going to disclose the timestamp as some evidence that the seed was innocuously generated."

And the disclosure happened now through Anthropic that is 100% not going to anger the NSA before the IPO and will have permission.