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Aug
5
reviewed Close How many degrees of freedom up my sleeve?
Aug
5
reviewed Close In symmetric searchable encryption are the algorithms public?
Aug
5
comment Homogenous and heterogeneous Unbalanced Feistel Networks
"The advantage of heterogenous UFNs is, that its internal properties change each round, making it more difficult to find specific characteristics which propagate through the different rounds" - is that correct? Or, does it make it harder to show that there is no such exploitable differential? Does the security of a heterogenous UFN depend on all (or at least, most) of the round functions? If so, why does using different ones make security better?
Aug
5
awarded  Enlightened
Aug
5
awarded  Nice Answer
Aug
4
comment About S-box in AES
@RichieFrame: nope, it's correct as it stands.
Aug
3
answered About S-box in AES
Aug
3
answered Cryptographically Secure Hash Algorithm with Very Specific Property
Aug
2
reviewed Close run length testing
Aug
2
reviewed Close Theoretical attack on RSA
Jul
28
comment OTT service using FPE
@e-sushi: actually, to answer the question "is it possible", the important thing to ask is "does the network that carries the Codec-encoded bitstream just move those bits from the sender to the receiver, or does it do any manipulation (such as doing some internal compression to save bandwidth on an internal link). If the system is just moving bits, I see no problem in sending encrypted bits -- if the system expects that is an actual signal (and so transforms that don't change the signal audibly are allowed), that makes the problem much trickier.
Jul
28
reviewed Leave Closed Understanding Lattice based cryptosystem
Jul
28
comment Why not the one-time pad with pseudo-number generator
Am I missing something? In step 4, you append the seeds to the ciphertext, and apparently send them in the clear. Why can't an attacker use those seeds to decrypt the message? If the answer is "because the attacker doesn't know the 'non-standard' constants in the key streams", well, that means that those non-standard constants are effectively the key to this system; using keys bolted into the system makes for, at least, very questionable security.
Jul
25
reviewed Close Key Derivation from random salted seed, HMAC and HMAC based KDF
Jul
25
reviewed Close Are there any Javascript CSPRNGs?
Jul
25
reviewed Leave Open Elliptic curve group over a prime finite field $F_p$
Jul
24
comment Vigenère cipher: Security when key length and plaintext length are the same
@tylo: I can't think of anything else anyone could add (except for possibly the mention of Venona as an example) -- why don't you convert your comment into an answer?
Jul
24
reviewed Close Secure way to store fixed size string of digits
Jul
23
reviewed Leave Open Why is MAC using nonce+message+hash(nonce+message+identifier) not the standard?
Jul
23
comment Different padding rules for Merkle–Damgård and Keccak/sponge function
@CGFoX: you can't have two distinct messages that pad into the same. For example, if one message (in binary) was 101101 and the other was 10110100, the first would pad to 101101100000, and the second would pad to 101101001000 -- they don't look the same.