9,751 reputation
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bio website github.com/CodesInChaos
location Frankfurt, Germany
age
visits member for 3 years, 2 months
seen 47 mins ago

Apr
25
revised Combining AEAD with RSA
corrected the link
Apr
24
comment Using the output of a stream cipher, how to guarantee the integrity of 4 bytes of data?
"Concretely use the stream as a key for SipHash" what do you want to say with that?
Apr
23
comment Using the output of a stream cipher, how to guarantee the integrity of 4 bytes of data?
Are you sure that the overhead actually matters? You could also use a MAC with small constant overhead, such as SipHash.
Apr
23
comment Using the same secret key for encryption and authentication in a Encrypt-then-MAC scheme
I recommend HKDF as the KDF when you want to derive multiple keys (for example encryption and MAC) from a single high-entropy master key(not a password).
Apr
22
awarded  Guru
Apr
22
revised How is CipherCloud doing homomorphic encryption?
added 970 characters in body
Apr
22
comment How is CipherCloud doing homomorphic encryption?
@adrenalion The letter, has two parts. One part is the DMCA notice for the images. The other (non DMCA part) is about the false, misleading and defaming statements.
Apr
22
reviewed Approve suggested edit on How is CipherCloud doing homomorphic encryption?
Apr
21
awarded  Mortarboard
Apr
21
awarded  Good Answer
Apr
21
revised How is CipherCloud doing homomorphic encryption?
added 213 characters in body
Apr
21
revised How is CipherCloud doing homomorphic encryption?
added 1788 characters in body
Apr
21
revised How is CipherCloud doing homomorphic encryption?
added 10 characters in body
Apr
21
revised How is CipherCloud doing homomorphic encryption?
added 378 characters in body
Apr
21
revised How is CipherCloud doing homomorphic encryption?
added 6409 characters in body
Apr
21
awarded  Enlightened
Apr
21
awarded  Nice Answer
Apr
20
comment A lower bound on the insecurity of CipherCloud?
They claim that their encryption is not deterministic and defeats frequency analysis. Which is a really weird claim and doesn't fit the encryption shown in Sid's screenshot.
Apr
17
comment Why is $h(H, m) = E(m, H) \oplus m$ insecure?
What exactly is the definition of $H$ and $E$? I guess $H$ is the IV or chaining value, and $E$ some form of encryption, but which? In particular which parameter is the key, and which the message? And is it AES, a PRP, or an ideal blockcipher?
Apr
16
comment Is it safe to assume Salsa20 to be a PRP?
Salsa20 takes 16 constant bytes for a reason. While it's build from a permutation, that permutation has some limitations and it has no key.