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10h
answered Chosen plain text and chosen ciphertext definitions clarification
21h
comment Proving an encrypted message contains (but does not 100% consist of) a plain-text message?
The OP would "actually prefer it to be impossible to prove". $\;$
21h
comment Proving an encrypted message contains (but does not 100% consist of) a plain-text message?
Why does it follow that the answer is yes?$\:$ (Unless somewhat bideniable PKE is known to be impossible, it's not clear to me that there must be an NP algorithm with a non-negligible probability of accepting encryptions of Z and a negligible probability of accepting encryptions of strings other than Z.) $\hspace{1.61 in}$
2d
comment Is Curve25519 vulnerable to private key exposure in the case of a bad RNG?
tools.ietf.org/html/draft-pornin-deterministic-dsa-00 $\;$
2d
comment Is Curve25519 vulnerable to private key exposure in the case of a bad RNG?
Yes, since that problem isn't affected by what group is being used. ​ ​
2d
comment Key Size for Symmetric Homomorphic Encryption Over the Integers
Where do they suggest those values? $\;$
2d
comment Proving an encrypted message contains (but does not 100% consist of) a plain-text message?
However, I strongly encourage you to think hard about the point of what you're planning, and whether using somewhat bideniable PKE would undermine that. $\;$
2d
comment Proving an encrypted message contains (but does not 100% consist of) a plain-text message?
Definitely, since ​ 0*1 = 0 = 1*0 ​ and ​ 0 ≠ 1 . ​ ​ ​ Somewhat bideniable PKE schemes will make it infeasible to prove anything about the plaintext. ​ ​ ​ ​ ​ ​ ​
2d
comment Proving an encrypted message contains (but does not 100% consist of) a plain-text message?
Well, with the encryption-randomness kept and the keypair assumed to have been generated honestly, most PKE schemes will allow such proofs. $\;$
2d
comment Proving an encrypted message contains (but does not 100% consist of) a plain-text message?
Well, with the encryption-randomness kept and the keypair assumed to have been generated honestly, most PKE schemes will allow such proofs. $\;$
2d
comment Proving an encrypted message contains (but does not 100% consist of) a plain-text message?
Will you still have the randomness that was used for the encryption? $\:$ Can the verifier assume that the keypair was generated honestly? $\;\;\;\;$
2d
comment In DGHV FHE, why noise $r$ can be in $(-2^{\rho'}, 0)$?
Yes. ​ ((x+((p-1)/2))%p)-((p-1)/2) ​ ​ ​ ​
2d
comment In DGHV FHE, why noise $r$ can be in $(-2^{\rho'}, 0)$?
The mistake is that you're just thinking about (elementary ) number theory, $\hspace{1.8 in}$ rather than using the symmetric representation. $\;$
Aug
28
comment In DGHV FHE, why noise $r$ can be in $(-2^{\rho'}, 0)$?
You are using a wrong representation. ​ ​
Aug
28
comment Are there ANY text strings that will generate the same SHA-512 Hash output?
Yes, but it's supposed to be hard to find an example. $\;$
Aug
27
comment Can iterated hashing be used to mitigate collision and preimage weaknesses?
Well, it adds a non-positive amount regarding collisions. $\;$
Aug
27
comment Proving set membership in less than log(N) bandwidth
No; it could be that for honest servers, the client will accept with certainty, but malicious servers can make the clients have an essentially-arbitrary probability of accepting. $\:$ (I don't know of any candidate schemes for which that would be helpful.) $\;\;\;\;$
Aug
27
comment Proving set membership in less than log(N) bandwidth
There could conceivably be probabilistic schemes which also have that property. $\;$
Aug
27
comment Randomness in Public Key Encryption
@mephisto : $\:$ Do you have a proposed definition for "security influencing randomness"? $\;\;\;\;$
Aug
27
comment Proving set membership in less than log(N) bandwidth
Note that what you're doing doesn't operate how you said it needs to - a malicious server can simply send an invalid alleged-branch to one client to get that client to come to a different conclusion as a client it acted honestly with. $\;$