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Nov
13
reviewed No Action Needed Perfectly secret cipher can leak about the key?
Nov
13
reviewed No Action Needed Strange MAC algorithm
Nov
13
comment Consequences of AES without any one of its operations
Hint: what does linearity mean? If $AES(x) \oplus AES(y) = AES(x \oplus y) \oplus c$, for any $x$ and $y$ (and a fixed, key-dependent $c$), how could this be exploited?
Nov
13
comment What is the use of segments in Cipher Feedback Mode (CFB)
@owlstead: ok, universally recognized by the cryptographically clueful. In any case, while I can come up with plausible scenarios where CFB mode with s=8 is the best solution, I cannot think of any scenario where OFB mode with s=8 is any better than, say, OFB mode with s=n.
Nov
13
revised What is the use of segments in Cipher Feedback Mode (CFB)
Made things a bit more explicit
Nov
13
revised Condition on Vector Boolean Function to be Bijective
added 2 characters in body
Nov
13
answered What is the use of segments in Cipher Feedback Mode (CFB)
Nov
13
answered Condition on Vector Boolean Function to be Bijective
Nov
13
reviewed No Action Needed Blowfish ECB mode: Tools for known-plaintext attack?
Nov
13
reviewed Reviewed Different Encryption schemes i have no idea to achieve
Nov
13
reviewed No Action Needed Verifiable, Distributed Secret Santa Assignments
Nov
13
reviewed No Action Needed Client encrypts AES key and send it to other clients using public key (RSA) and server?
Nov
13
reviewed Close What is the bilinear pairing?
Nov
12
reviewed Leave Closed RSA: Fermat-Euler Theorem - coprimality of message and modulus
Nov
12
reviewed No Action Needed ASP.NET MembershipProvider uses passwordSalt when encrypting
Nov
12
revised Are post-quantum cryptographic ciphers *also* secure if the P=NP conjecture holds true?
added 210 characters in body
Nov
12
answered Are post-quantum cryptographic ciphers *also* secure if the P=NP conjecture holds true?
Nov
12
comment Permutation parity after cycle-walking
On the contrary, if the two halves of the Feistel state are $a, b$, then the update 'a += F(k, b)' can be odd; in fact, it will be if an odd number of the $F(k, b)$ values are odd (fixed $k$, over all possible values of $b$).
Nov
11
comment Permutation parity after cycle-walking
The standard trick for small block Feistel ciphers is to use modular addition, rather than xor, in each round; that way, the round, and hence the permutation, has a 0.5 probability of being odd.
Nov
11
reviewed Leave Open what is SALSA20 Nonce and its requirements