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Dec
10
comment Statistical properties of hash functions when calculating modulo
Yes. ${}{}{}\;$
Dec
9
comment Statistical properties of hash functions when calculating modulo
$\operatorname{mod} \hspace{.04 in} 2^{80} \:$ will just give you the left or right 80 bits, depending on whether you use big or little endianness. $\;\;\;$
Dec
9
comment Looking For Additively Homomorphic Encryption
I wouldn't mind. $\;$
Dec
9
revised Looking For Additively Homomorphic Encryption
fixed sentence fragment
Dec
9
answered Looking For Additively Homomorphic Encryption
Dec
8
comment Looking For Additively Homomorphic Encryption
The idea is just using that FHE over the integers's "noise" increases far less quickly for addition than for multiplication. $\;$
Dec
8
comment Looking For Additively Homomorphic Encryption
Would leveled additively homomorphic encryption suffice? $\:$ (key size grows linearly in the depth it must be able to handle) $\;\;\;\;$
Dec
6
comment Should we MAC-then-encrypt or encrypt-then-MAC?
I suspect you meant "confidentiality". $\;$
Dec
6
comment Should we MAC-then-encrypt or encrypt-then-MAC?
... You're supposed "to have plaintext integrity" and "be able to read it" -- the 'inner' $\hspace{.98 in}$ decryption is for the latter, and the MAC is for the former. $\;$
Dec
5
comment Creating serial key generator using ECDSA, how to get signature short enough?
BLS or maybe "very short weakly secure signatures" or "shorter signatures with random oracles", $\hspace{.08 in}$ although for the latter two, security will generally degrade significantly as more messages are signed $\hspace{.35 in}$
Dec
4
comment Why is proving “parties' views are simulatable” enough in semi-honest model?
For example, malicious-Alice could change a wikipedia article that Bob will use to decide on his input. $\hspace{.24 in}$
Dec
4
comment Why is proving “parties' views are simulatable” enough in semi-honest model?
honest-Alice "doesn't know the value of $y$", but adversary-Alice chooses the value of $y$. $\hspace{1.11 in}$
Dec
4
comment Why is proving “parties' views are simulatable” enough in semi-honest model?
Proving that "parties' views are simulatable" is enough in the semi-honest model because Alice can distinguish $y$ from $y'$. $\;$
Dec
4
revised Why is proving “parties' views are simulatable” enough in semi-honest model?
fixed title's grammar
Dec
4
comment Why is proving “parties' views are simulatable” enough in semi-honest model?
"about the proof in semi-honest model" is not a question. $\:$ Do you mean "What is wrong with my proof about a protocol in the semi-honest model?"? $\;\;\;\;$
Dec
4
comment Should we MAC-then-encrypt or encrypt-then-MAC?
... Yes we are, otherwise there would be no point to any of these constructions. $\;$
Dec
4
comment Should we MAC-then-encrypt or encrypt-then-MAC?
"the MAC is not meant to preserve the integrity of the plaintext" would be just as good a reason to avoid MAC-then-encrypt too. $\;$
Dec
2
comment Creating serial key generator using ECDSA, how to get signature short enough?
If signature length is an issue, why are you public-key-encrypting the signatures? $\:$ A scheme with $\hspace{.24 in}$ shorter signatures "is the way to go for generating serial keys". $\;\;\;\;$
Dec
2
comment Creating serial key generator using ECDSA, how to get signature short enough?
Why are you specifying ECDSA? $\;$
Dec
1
comment Implementing a pseudo random function in practice
No, I'm saying that for most hash functions (even MD5), HMAC is believed to be a PRF. $\:$ I do not know whether something similar holds for CMAC, although there is another construction that's based on CMAC. $\:$ Every PRF with large output space is a MAC, but if there is a MAC then there is a MAC that is not a PRF. $\;\;$