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Jul
21
reviewed Close How does the Hashlet work?
Jul
20
revised AES-CTR-256 Sub Keys With Encrypted Sub Key Index
Fixed grammar
Jul
20
comment Security equivalent to Diffie–Hellman problem?
@RickyDemer: generally, we do Diffie-Hellman in groups of known order; if you are doing it in the RSA group, an alternative way to compute $g^{b^{-1}}$ is to do a DH with $g^b$ as the base $h$, and the two public values $h^x=h^y=g$; the Oracle will return the value $h^{xy} = g^{b^{-1}}$. As for the other direction where $b$ might not be invertable (and so $b^{-1}$ doesn't exist), we can replace $b$ with $b+i$ for known $i$; with nontrivial probability, we can find an $i$ where inverse exists; given $g^{a(b+i)}$, it's easy to recover $g^{ab}$
Jul
20
answered Security equivalent to Diffie–Hellman problem?
Jul
20
reviewed Close Cryptolocker 2.0 ransomed #1.23 btc
Jul
20
reviewed Close Video encryption at server, decryption on mobile using AES
Jul
20
comment Turning PRPs in PRGs with a counter
@Sklivvz: when was the last time you generated 1 TiB of output from a random number generator? In any case, if you need to generate more, all you need to do is periodically rekey the block cipher.
Jul
20
answered Turning PRPs in PRGs with a counter
Jul
19
reviewed Leave Closed Attacks on Full TripleDES
Jul
19
reviewed Close LFSR and Markov chain question
Jul
19
reviewed Looks OK Can a EC private key be derived from a public key?
Jul
19
reviewed Delete Is there a cryptographic function or system in which it becomes HARDER to break as time passes?
Jul
19
answered Can a EC private key be derived from a public key?
Jul
18
answered How to calculate complexity of ElGamal cryptosystem?
Jul
17
reviewed Close Test PFS / EC-DHE authentication support
Jul
17
reviewed Reopen Security Model of Group Key Transfer Protocols
Jul
16
reviewed Close Does having a known plaintext prefix weaken AES256?
Jul
16
reviewed Leave Open Does bad IV generation weaken CBC?
Jul
16
reviewed Close Security Model of Group Key Transfer Protocols
Jul
16
reviewed Leave Open Can I crack an AES string if I have all these parameters?