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Sep
3
revised RSA PCKS1 v2.1 RSAES-OAEP algorithm
added 128 characters in body
Sep
3
answered RSA PCKS1 v2.1 RSAES-OAEP algorithm
Jul
16
accepted Questions on rank-attacks in Multivariate Cryptography
May
30
comment What is a definition of a nonce?
...what I'm trying to say is that, I think that a definition of a nonce should not impose ANY other requirements other than that it should not be used more than once. This does not forbid you from putting additional constraints on it.
May
30
comment What is a definition of a nonce?
You asked for a definition of a nonce, and I provided what I consider to be the "right" notion; namely a value which is simply not used more than once (that's it!). Unfortunately there's much ambiguity in how the terms nonce and IV's are used in practice. So you might see several sources calling the first input to CBC-mode a nonce, whereas I would have preferred calling it an IV.
May
30
answered What is a definition of a nonce?
May
8
awarded  Informed
Apr
19
comment PKC McEliece + $S$ + $P$
As per your own Wikipedia link: $S$ is simply any invertible binary $k \times k$ matrix, and $P$ is any $n \times n$ permutation matrix. What is it that you find unclear?
Mar
17
awarded  Yearling
Mar
16
accepted Proof of the standard pseudorandom generator + XOR encryption scheme in Goldreich
Mar
16
comment Proof of the standard pseudorandom generator + XOR encryption scheme in Goldreich
Exactly the answer I was looking for, thx! It's funny though: I had done exactly the same thing as you, including the consideration of the "triangle" inequality. But, when I got to your last equation, I couldn't figure out where that $1/2$ factor should come from. However, its good too see that I wasn't to far of :)
Mar
16
asked Proof of the standard pseudorandom generator + XOR encryption scheme in Goldreich
Feb
28
awarded  Commentator
Feb
28
comment Is SHA-1 still practical secure under specific scenarios?
I think it should be mentioned that the security guarantees given by that HMAC-paper is disputed. See Another Look at HMAC and the youtube presentation Another look at provable security. While controversial, they do bring up relevant points to the practical (security) merit of the Bellare paper.
Feb
16
comment How can an S-Box be reversed?
I think you should make it clear that S-boxes often ARE invertible. For instance, the S-box in AES is invertible. @Liam Inverting S-boxes can be very easy: you simply create a lookup table that reverse all the possible substitutions of the S-box. E.g. if the S-box maps 0xA5 to 0x3F (this would be an 8x8 S-box), then the inverse transformation would map 0x3F to 0xA5. Thus, you simply enumerate all the possible values the S-box can have, and create an inverse table that "undoes" all those transformations (this effectively limits how large the S-boxes can be in practice).
Feb
15
comment Encrypting a key with the same key
@madhukar2k2 "I tried searching for an answer for the above, but couldnt not find one." - try looking at circular security, it might give you some answers. Additionally, I've added some things in my answer below.
Feb
15
answered Encrypting a key with the same key
Feb
1
revised Questions on rank-attacks in Multivariate Cryptography
Added another question and changed the title of the question
Jan
29
revised Questions on rank-attacks in Multivariate Cryptography
added 1 characters in body
Jan
28
asked Questions on rank-attacks in Multivariate Cryptography