Quote from: TPTB_need_war on May 05, 2016, 02:01:40 AM

Click this quote to read what Gmaxwell and others will respond:

Quote from: TPTB_need_war on May 05, 2016, 01:39:14 AM

Wholly shit! I am contemplating the possibility that Craig has revealed that who ever created Bitcoin put a backdoor in it!

As I already explained, the signature Craig has provided proves either he has cracked something about the way Bitcoin uses SHA256 or he has Satoshi's private key. Afaics, there are no other mathematical possibilities.

But note this small detail:

Quote from: https://github.com/patio11/wrightverification

You'll note that Bitcoin, for reasons known only to Satoshi, takes the signature of hash of a hash to generate the scriptSig. Quoting Ryan:

Well that isn't so insignificant of a detail when you think more about it in this context.

A cryptographic hash function has a property named collision resistance. Collision resistance is related to preimage resistance in that if we have a way to quickly find collisions, then if the preimage is collision then we also break the preimage resistance for that particular hash value.

Collision resistance is normally stated as the number of hash attempts required to find a collision or the number of rounds to break collision resistance with reasonable hardware. Normally this is exponentially less than computing the SHA256 hash function 2²⁵⁶ times. For SHA256, there are collision resistance attacks up to 46 of the 64 rounds of SHA256 (and 52 of 64 rounds for preimage attack).

So what happens to collision (and preimage in this context) resistance when we hash the hash? Well all the collisions from the first application of hash become collisions in the second hash, plus the new collisions in the second application of the hash thus increasing the number of rounds that can be attacked.

It seems likely that Craig has identified the back door that was placed in Bitcoin as explained above, and used his supercomputer access to find a preimage of SHA256.

If am correct, this is major news and Bitcoin could crash.

I urge immediately peer review of my statements by other experts. I have not really thought deeply about this. This is just written very quickly off the top of my head. I am busy working on other things and can't put much time into this.

I have now reviewed your analysis and have concluded you are talking out of your ass.