33,216 reputation
566129
bio website bolet.org/~pornin
location Quebec City, Canada
age 39
visits member for 3 years, 5 months
seen yesterday

Cryptographer, programmer in several languages (C, Java, several assemblies, Pascal, Forth...). I also have a life.


Dec
6
comment When to use RSA and when ElGamal asymmetric encryption
Considering that RSA, the algorithm, was published and fully described in 1978, several years before RSA, the company, was actually founded (in 1982), your assertion is dubious. It would imply that not only NSA paid the company to modify the algorithm, but also gave them access to some time travel technology so that they may get back to 1978 to enact the said modification. (I guess I am in denial of the NSA time travelling powers. Shame on me.)
Dec
2
awarded  Nice Answer
Nov
29
awarded  Enlightened
Nov
29
awarded  Nice Answer
Nov
28
answered Is there an alternative AES schedule?
Nov
26
comment What is the post-quantum cryptography alternative to Diffie-Hellman?
I am not saying that a "quantum-threatened" asymmetric encryption algorithm can be used safely for key agreement even in the presence of an attacker with a quantum computer. What I am saying is that any asymmetric encryption algorithm can be used for key agreement; so any quantum-safe asymmetric encryption algorithm is also a quantum-safe key agreement algorithm.
Nov
23
comment Three-way hash collision
When $n$ is large, $n^3/6$ and $n(n-1)(n-2)/6$ are almost the same thing. When talking about approximations (as is the case here), this kind of shortening is valid.
Nov
22
answered Addition / Multiplication modulo 13
Nov
14
answered How many of primitive point on the elliptic curve?
Nov
14
awarded  Enlightened
Nov
14
awarded  Nice Answer
Nov
13
awarded  Enlightened
Nov
13
awarded  Nice Answer
Nov
6
answered Zero Knowledge Example using discrete log
Nov
5
awarded  Enlightened
Nov
5
awarded  Nice Answer
Nov
2
revised Openssl & RSA : how many public exponents are possible?
added 1826 characters in body
Nov
2
comment Openssl & RSA : how many public exponents are possible?
@owlstead: if you use RSA without a proper padding procedure, then it is malleable, and this is easier to exploit if $e$ is small. However, the issue there is not a small $e$, but lack of proper padding.
Oct
24
comment AES-GCM Disadvantage
One may add a performance issue: the not-too-slow implementations of GCM use tables that exhaust L1 caches on small architectures (like the 32-bit Mips found in cheap home routers). It has been reported that on such systems, EAX mode outperforms GCM.
Oct
23
comment Interpretation of the results of NIST (p)NRG suite
Here it is the other way round. Usually, in statistics, you want to detect a non-random effect (e.g. a correlation between a specific gene mutation and a given illness), so you want a small p-value, that would mean "no way this is pure luck, there must be some correlation". Here we really don't want correlations or biases, so we want big p-values.