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 Dec 15 awarded Nice Answer Dec 14 awarded Popular Question Dec 10 comment Can homomorphic decryption of DES be practical? @MaartenBodewes The algorithm doesn't need to be encrypted, but it does need to be realized as a homomorphic circuit... Nov 14 comment Does complicating a flawed algorithm make it secure? The answer is trivially "yes" since every secure encryption algorithm can be viewed as "added complexity" on top of the flawed identity cipher (which encrypts all plaintext to itself). But that is probably not the answer you wanted.. you need to be an expert to work out how to complicate it in a way that adds security. Nov 12 awarded Nice Answer Nov 11 revised Why can't I reverse a hash to a possible input? added 38 characters in body Nov 11 answered Why can't I reverse a hash to a possible input? Nov 9 comment What is the difference between “securely realizes” and “securely implements”? You can also say "X is realized by Y" if that is less awkward to you. Ultimately it just means "to make real, concrete". Oct 30 comment How is bitslicing faster? @IlmariKaronen Fair enough, after reading your comments and the new answers I now agree it's sufficiently on-topic Oct 29 comment How is bitslicing faster? Is this really on-topic on Crypto SE? Oct 25 comment I read ECB is bad because the same plaintext outputs the same ciphertext. Isn't that a requirement of a cipher? I think a good addition to this answer would be to add a paragraph about how it's possible for a cipher to encrypt non-deterministically. The word "initialization vector" is referred to once and never explained. Oct 21 comment Is there an existing cryptography algorithm / method that both encrypts AND compresses text? The statement is correct, just somewhat awkwardly phrased. It is obvious that you cannot compress every single $n$-bit string into less than $n$ bits. You can compress some of them by exploiting redundancy (like repeated patterns of bits and so on), but others with less structure have to become larger after compression, at least by a single bit, to compensate, because information theory. So on average (and hence to guarantee correctness in all cases) the output must be as large as the input, or you will eventually truncate some input that didn't compress well (like, say, random bits). Oct 14 answered Adding dummy bytes to ciphertext Oct 9 comment Is there a cryptographic protocol that let's me prove someone has a large binary? I don't have a full answer but I feel like a Merkle tree could probably tackle this kind of problem, maybe as part of some randomized protocol. Maybe someone else is more familiar with this. Oct 7 comment Is it safe to initialize secret keys by just reading /dev/random on Linux? @UnixJunkie The zero byte is a value just like any other, don't count on being able to store uniformly random data in null-terminated strings ;) Oct 6 comment Generating unbiased numbers with a biased six sided die? If Alice doesn't know the odds then she could also adapt the good old low-tech (but extremely clever) "unfair coin" technique, which might not be optimal but is easy to understand and thus probably more useful in real life with actual dice when two parties are trying to reliably use a biased die to carry out some kind of business. The unfair coin technique: roll twice, then HH -> rethrow, TT -> rethrow, HT -> output 0, TH -> output 1. I'm sure a variant could be devised for six-sided dice. Oct 3 comment Can machine learning analyze random number generator? This (probably) won't work. There is certainly structure in CSPRNG's that could potentially be exploited, but I don't believe naive classification will be powerful enough to yield a distinguisher for any nontrivial CSPRNG. Sep 27 comment RSA: special parameters construction Isn't $q$ going to be super small (assuming $e$ is small), given the density of the primes? Sep 20 comment Maximum steganographic embedding rate not detectable by steganalysis? Are you interested in scenarios when the detector may alter, corrupt, or delete part of the carrier (requiring redundancy and error correction, thus reducing embedding rate) or just the simplest case with a passive detector? Aug 24 comment Encryption of 8 bit of block data Does it have to be a block cipher?