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comment Examples of modern, widely used ciphers that suddenly fell?
Should we indicate in the question that we are talking modern ciphers that operate on bits rather than text? That way we can exclude the ciphers before the computer age for this already broad question.
Apr
29
comment Elgamal with secret key equal to zero possible?
You could wonder if it wouldn't be better to generate an all zero value and detect that there is a problem instead of generating a 1 and all zero's, which is equally insecure and doesn't show this issue. Having the implementation test for 0 and 1 and then break off with a strong warning that the PRNG is broken seems to be the best option. If the RNG was already tested you could just let it be.
Apr
29
comment How secure is the OTR protocol?
@otus Hmm, we already have a "yes, if the implementation is secure" answer, without much further depth. I'm still not sure if this question isn't too broad. I'll leave it be, but people may want to consider the value of the answers provide below.
Apr
29
comment Unknown Hash or Cipher
If it was generated by a keyed hash (e.g. HMAC) you would never find out. Your only hint would be the size of the encoded binary value. This puzzle is likely only going to frustrate you; I'd suggest you stop.
Apr
29
comment Currently Best Integer not bit FHE
You're not indicating what exactly is the problem with HELib, "unclear what you're asking" is one of the reasons to vote off topic. You're asking for FHE's that evaluate on encrypted integers, which is asking for references, which is off topic as well. Which one is best is asking for opinions, again: off topic. Please ask specific questions, do not assume we will do research for you.
Apr
28
comment Symmetric cipher speed (AES vs Camellia vs Twofish)
The final speed of ciphers depend on their implementation. If you want to perform a good comparison instead of hand-waving, you should compare the algorithms on a reference system using the algorithm implementations of your choice. If you're really serious about speed, you're more likely to find AES hardware implementations (e.g. AES-NI or ARM instructions) than Twofish implementations.
Apr
28
comment Currently Best Integer not bit FHE
What do you mean with "evaluates"? HELib readme shows that addition is supported; I suppose that they don't mean bit addition there, as bit addition is somewhat boring.
Apr
28
revised RSA encryption using multiplication
secret key -> private key, more commonly used for public / private key pairs
Apr
28
comment Best known attack
According to my answer that would be the one that compromises the security the most. What kind of information are you missing? What kind of conditions do you set? Please be as specific as possible.
Apr
28
comment Is there a standard for OpenSSL-interoperable AES encryption?
Ah, so openssl pkcs7 doesn't exist? Note the final question: "Is there a standard for OpenSSL-interoperable AES encryption?"
Apr
28
revised mode of operation in cryptography
added MAC / HMAC terms
Apr
28
revised mode of operation in cryptography
deleted 195 characters in body
Apr
28
awarded  modes-of-operation
Apr
28
revised mode of operation in cryptography
added 90 characters in body
Apr
27
comment How robust is my coded output?
@Biv Yeah, your answer there practically takes care of the information of the comments here and the second part of my answer. They are nicely in sync :)
Apr
27
comment How robust is my coded output?
ECRYPT (EU) uses to run stream cipher competitions. I'm not sure if anybody is really interested in non-authenticated block ciphers - we've quite a few good ones. I could imagine tweakable block ciphers become subject to one. If that happens, look here (competitions at Dan Bernsteins cr.yp.to site)
Apr
27
comment How robust is my coded output?
Your current question isn't off topic Clarence - I would not have answered it if that was the case. But we get quite a few questions that simply show some ciphertext or a newly thought out algorithm and we have to close those. This was just a small reminder not to post such questions to you and other aspirant cryptographers.
Apr
27
comment How robust is my coded output?
Note that requests for analyzing a cipher are off topic here. You can however ask if specific parts of your design are considered secure with regards to current practices or not. Overly broad questions or questions that require original research shouldn't be asked here.
Apr
27
answered How robust is my coded output?
Apr
27
comment Backdoor in NIST elliptic curves
@SEJPM Smells like an answer to me, if you combine the two comments.