19,602 reputation
32171
bio website
location
age
visits member for 2 years, 11 months
seen 14 hours ago

Dec
28
revised Automated security protocol verification tool for eCK model
Improve the title to be represent the question more accurately.
Dec
26
answered How to prove that a ciphertext is encrypting multiplication of two values?
Dec
26
comment Zero knowledge proof protocol example?
Paul Wagland is 100% correct. If Bob is teasing (he is lying, and Alice is actually wearing two same-color gloves), then there's no way Bob will be able to fool Alice into thinking her gloves are mismatched. But, if Bob claims that Alice is wearing matched gloves, Alice has no way to tell whether Bob is telling the truth or not (Bob might have noticed that Alice is wearing mismatched gloves and decided to lie about it; then when they conduct the ZKP, he answers randomly). In other words: there's a proof that Alice's gloves are mismatched, but there's no proof that Alice's gloves are matched.
Dec
26
comment Does the key schedule function need to be a one-way function?
This question is not clear about what function is/isn't one-way. And, I can't make any sense of the very first sentence of the post. (Are you perhaps making some assumptions about what a key schedule must look like? If so, those assumptions are not valid. Many key schedules don't look anything like that.) Anyway, I think the question is poorly framed; it is too hard to tell what you're asking.
Dec
26
answered Security Level Estimate when Cascading/Compositing Ciphers?
Dec
26
comment Security Level Estimate when Cascading/Compositing Ciphers?
You've loaded too many questions together into one. Please pick one question per question. Your first question is too broad; the answer will depend upon whether you're talking about a block cipher or something else. I suggest you just tell us about the real problem you have; or else ask multiple separate questions.
Dec
23
answered Can the passphrase of a PGP key be deduced from an old backup?
Dec
23
comment Now that quantum computers have been out for a while, has RSA been cracked?
This answer does not seem to add any added value over the existing answers.
Dec
22
answered Can we ensure the security of a crypto-algorithm and -implementaton against acoustic cryptanalysis?
Dec
20
comment Is this algorithm demonstrating “proof of work”
In the future, we generally ask that questions on Crypto.SE should use pseudocode to describe the algorithm concisely -- rather than giving a full implementation. Here the code makes it harder to understand what is going on, whereas you could describe the basic algorithm in one or two lines of simple mathematics. Just letting you know for the future....
Dec
20
comment Is this algorithm demonstrating “proof of work”
@kylek, I think you've misunderstood rolfl's answer. Rolfl is 100% correct on both of his criticisms, and I think you misunderstood his points and haven't fully grokked his critique yet. Maybe read it a second time? (Rolfl clearly does understand that this is for proof-of-work, not for authentication.)
Dec
20
answered Is this algorithm demonstrating “proof of work”
Dec
19
comment Are those two distributions indistinguishable?
Thanks, @curious, that was a typo on my part. I certainly intended it to be mod $N^2$, but that did not make it from my brain to my fingers -- oops. Fixed. Thank you again.
Dec
19
revised Are those two distributions indistinguishable?
added 2 characters in body
Dec
19
answered Are those two distributions indistinguishable?
Dec
19
comment Are those two distributions indistinguishable?
Are you sure you've got the definition of the decisional quadratic residuosity problem right? Do you have a reference? I'm not familiar with this specific hardness assumption, but based on the name, I would have expected something called the "decisional quadratic residuosity problem" to be about $x^2 \bmod N^2$ vs $r \bmod N^2$.
Dec
19
comment Is a Mersenne-twister cryptographically secure if I truncate the output?
Greg, the first step is to start by asking questions rather than drawing conclusions (such as the conclusion that Mersenne Twister is fine). You should be especially careful when your conclusions seem to run counter to what others have told you. Asking questions shows that you want to learn. Here's a starting tip: Mersenne Twister is insecure from a cryptographic perspective, and the fact that you only output partial output does not change that. You need cryptographic-level security, and the best way to get that is a CSPRNG -- which Mersenne Twister is not.
Dec
19
comment Is a Mersenne-twister cryptographically secure if I truncate the output?
Wow. There's a pretty impressive amount of misconception shown here. All I can say is: You are not qualified to write a casino game. Don't do it. There is specific technical knowledge required to do this right, and you do not have it. Try to find someone more qualified to do this aspect of design, because your instincts are leading you astray, your reasoning is wrong, your conclusion is wrong (and worse, you seem convinced that you are right).
Dec
17
answered Attacks against El Gamal private key
Dec
17
revised Help with linear cryptanalysis
Add Matsui paper.