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Mar
3
comment Check the validity of a rsa key pair with only the public key?
Also, Atsch could check that the modulus is not a perfect power. $\;$
Mar
3
comment Is it meaningful to consider the leakage of master key of KGC?
(... continued) $\:$ and a collision-resistant hash family that can be sampled along with a unique secret that can be recomputed from any collision, then one can remove the bounded-id-length condition. $\:$ If one additionally has a fixed-input-length random oracle, then one can replace selective-id security with full security at the cost of there being a special setup string such that completeness (but not confidentiality) will fail for an exponentially small fraction of those setup strings. $\;\;\;$
Mar
3
comment Is it meaningful to consider the leakage of master key of KGC?
Also, Binary Tree Encryption is trivially sufficient for bounded-id-length, selective-id IBE which has the property sought, where the total storage required grows linearly with the number of user keys forgotten so far. $\:$ (By information-theoretic arguments, that growth must be at least linear, although one could hope for better dependence on the security parameter.) $\:$ If one uses a KDF $\:$ (continued ...) $\hspace{1.47 in}$
Mar
2
comment Check the validity of a rsa key pair with only the public key?
The only such scenario I'm aware of is NIZK proofs. $\;$
Mar
2
comment Check the validity of a rsa key pair with only the public key?
crypto.stackexchange.com/q/1611/991 , crypto.stackexchange.com/q/13260/991 $\hspace{1.69 in}$
Mar
2
comment Is it meaningful to consider the leakage of master key of KGC?
eprint.iacr.org/2011/612.pdf $\;$
Mar
2
revised If $G'(s)=G(s0^{|s|})$ and $G$ is a PRNG, is $G'$ necessarily a PRNG?
used pseudocode
Mar
2
answered If $G'(s)=G(s0^{|s|})$ and $G$ is a PRNG, is $G'$ necessarily a PRNG?
Mar
1
revised Is it meaningful to consider the leakage of master key of KGC?
elaborated in response to comment
Mar
1
comment NTRU crypto from unseen.is; myth busting help
They are offering encryption for somewhat general use, and transcripts can be archived with the hope of later acquiring a quantum computer to break the key exchanges. $\;$
Mar
1
comment NTRU crypto from unseen.is; myth busting help
"super strong" might be bold, but the rest of that particular statement isn't. $\;$
Mar
1
answered Is it meaningful to consider the leakage of master key of KGC?
Feb
28
comment Cryptographic Protocol using NaCl
Does NaCl offer forward-secure symmetric crypto? $\:$ I think that would be more $\hspace{1.38 in}$ efficient than having the server stay involved. $\;\;\;$
Feb
27
comment Is sharing the modulus for multiple RSA key pairs secure?
I'm saying that one could choose $d$ to be a multiplicative inverse of $e$ modulo $\:\operatorname{L}\hspace{-0.03 in}\operatorname{cm}\hspace{.02 in}(\hspace{.04 in}p\hspace{-0.04 in}-\hspace{-0.05 in}1,q\hspace{-0.04 in}-\hspace{-0.05 in}1)\:$,$\:$ so if your argument requires that they be multiplicative inverses modulo $\phi$, then you should give that as an assumption rather than an automatic fact. $\;\;\;\;$
Feb
27
comment Is sharing the modulus for multiple RSA key pairs secure?
I don't see him saying $\;\; e\hspace{-0.03 in}\cdot \hspace{-0.03 in}d \: \equiv \: 1 \pmod{\phi} \;\;$ anywhere. $\;\;\;\;$ RSA only requires that $\;\; e\hspace{-0.03 in}\cdot \hspace{-0.03 in}d \: \equiv \: 1 \: \pmod{\lambda} \:\:\:$. $\;\;\;\;$
Feb
26
comment Is sharing the modulus for multiple RSA key pairs secure?
$\phi(N)$ should be replaced with $\:\operatorname{L}\hspace{-0.02 in}\operatorname{cm}(\hspace{.04 in}p\hspace{-0.04 in}-\hspace{-0.05 in}1,q\hspace{-0.04 in}-\hspace{-0.05 in}1)\;$. $\;\;\;$
Feb
25
comment Decode message $m = p * q$, where $p ^ 5 \bmod N$, $q ^ 5 \bmod N$ and $N$ are known
@fgrieu : $\:$ When the three known values are 3,3,6$\hspace{.02 in}$, 9 is the unique compatible value of m. $\hspace{1.01 in}$
Feb
20
comment Get permutations from password
Does it need to be a way that one could imagine being implemented mechanically? $\hspace{1.63 in}$
Feb
18
comment Secrete message sharing using N private keys
It is also not clear where $\:pub\:$ comes from. $\;\;\;$
Feb
16
answered Does a cofactor of an elliptic curve have to be an integer?