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 Jul 12 awarded Yearling Dec 22 awarded Critic Dec 22 comment AES key length greater than 256 bits - is it dangerous to do an implementation outside of the standard? hunter: r.e. the other code that's assuming things about the key length: I was looking at things like line 264: if( Nk > 6 && idx % Nk == 4 ). I understand what it's doing for standard values for Nk (where Nk is the number of 32-bit words in the key), but it's clearly not just the obvious extension of AES for longer keys. Dec 22 answered AES-GCM and its IV/nonce value Dec 19 comment tower of extension field Your twisted curve is over $q^6$, no? So a point on it would be expressed in the form ((a,b),(c,d),(e,f)), ((g,h),(i,j),(k,l)). (That is, an (x,y) pair of triplets of pairs). The function that maps a point on the twist curve to the point on the normal curve over $q^{12}$ is the group homomorphism. The homomorphism in the paper above is (x,y) -> (ω²x, ω^3y), but yours may vary. Dec 19 comment AES key length greater than 256 bits - is it dangerous to do an implementation outside of the standard? Via that link, on line 251 (code.google.com/p/as3crypto/source/browse/trunk/as3crypto/src/…) the code is setting the number of rounds based on the size of the key. There is other logic in that function that assumes a standard key length. I think that fact that it doesn't check the key length is a bug and, by using a non-standard one, you're using a custom variant of AES that has never been studied. Dec 19 answered AES key length greater than 256 bits - is it dangerous to do an implementation outside of the standard? Dec 19 answered tower of extension field Jul 12 awarded Yearling Aug 28 awarded Enlightened Aug 28 awarded Nice Answer Aug 2 awarded Beta Jul 18 answered Is it possible to create an asymmetric cryptosystem where the private keys are not easily verifiable as such? Jul 14 awarded Supporter Jul 13 answered Protocol to generate Client Certificates at the start of a SSL session automatically? Jul 12 awarded Editor Jul 12 revised How to provide secure “vanity” bitcoin address service? Change from ** to ^ Jul 12 awarded Teacher Jul 12 answered How to provide secure “vanity” bitcoin address service?