2,666 reputation
516
bio website github.com/orlp
location Leiden, Netherlands
age 20
visits member for 2 years, 2 months
seen 1 min ago

Computer Science undergraduate and cryptography enthusiast. Currently unemployed and looking for opportunities. You can contact me at orsonpeters@gmail.com.

Favourite languages: C++, Python, Rust, C.

Achievements:


Jan
24
comment Can curve25519 keys be used with ed25519 keys?
@owlstead Sorry, I meant the cryptographers that develop the primitives themselves - they almost never release a Java library. There are a few "cryptography suites" as you've cited, that implement many primitives, but outside of those big suites there isn't much high-quality Java cryptography software available. This means that if you want to use modern cryptography, like Ed/Curve25519, ChaCha, Keccak, BLAKE, Poly1305, that you'll either have to implement it yourself or trust an often badly performing non-scrutinized third-party implementation.
Jan
22
comment Can curve25519 keys be used with ed25519 keys?
@Gracchus I think you should look into using a C library from Java - there are almost no cryptographers writing libraries in Java.
Jan
22
answered Can curve25519 keys be used with ed25519 keys?
Jan
12
comment Methods of making ASIC/GPU resistant encryption?
What do you mean with "an encryption scheme", and please define how should it be resistant against ASIC's and GPU's (like what attacks should it be able to defeat)?
Jan
7
awarded  Yearling
Jan
5
comment How can I solve congruence modulo N?
And in fact the statement should be the other way around, namely "finding $a$ is no harder than factoring $N$". Then as an interesting side note you may say that this is the fastest known method, but it is by no means proven optimal.
Jan
3
comment function of crypt called “ICE”
Then what is your question? The source code is freely available.
Jan
3
comment function of crypt called “ICE”
Have you, eehm, tried to google for ICE?
Jan
1
comment How can I solve congruence modulo N?
So did you mean $J_Aa^e \equiv 1 \mod n$, with $n = pq$, $1 < J_A < n$, $0 < e < n, gcd(e, (p-1)(q-1)) = 1$, $gcd(J_A, n) = 1$ and $a \in \mathbb{Z}$?
Jan
1
comment How can I solve congruence modulo N?
What are $J_A$ and $e$?
Dec
30
comment A timestamping authority (digital notary)
This service is a pretty popular one and has been up for a long time. It's not an "instant" API though, it uses emails and it seems to send your stamp at the end of the day.
Dec
30
comment Are hash trees an alternative, quantum-resistant signature scheme which can replace RSA?
@Reid I did some searching and found the paper. It's exactly what I remembered. Bernstein argues that BHT will never be superior to Grover's in price/performance thanks to the largely inferior memory usage. Running parallel instances of Grover is more cost effective, making BHT obsolete.
Dec
29
comment Are hash trees an alternative, quantum-resistant signature scheme which can replace RSA?
@Reid If I recall correctly Daniel Bernstein analyzed the two algorithms and concluded that no attack will ever be cheaper using Brassard-Hoyer-Tapp then Grover's due to the memory requirements, therefore only $2^{n/2}$ should be taken account for in terms of security levels.
Dec
27
comment Keeping IV secret for AES CFB mode
@M.C. Please stop. There's too many factors/details that can go wrong so I can't simply say your usage is secure. I'd have to look at the actual code/application (and sorry, I'm not doing free work). I'm answering crypto questions in my free time, not doing security audits. I have given you the parameters for correct CFB usage in my answer - it's your job to make it so. And please do not use weasel words while communicating about crypto - there's no such thing as a "cryptographically secure algorithm" that generates IVs and keys. Did you mean a CSPRNG?
Dec
27
comment Keeping IV secret for AES CFB mode
@M.C. Depends on how you use it. Sorry.
Dec
27
comment Keeping IV secret for AES CFB mode
@M.C. With all due respect, I'm going to refrain from saying "the best" about this. Most things are secure if used properly, but what defines properly changes from mode to mode. I can't say what the best mode is for 32 byte data encryption because it's a non-existing question. There's always many other considerations such as speed, parallelizability, changing keys/iv's, database capacity, latency, cipher requirements, etc, etc. It always depends on the application.
Dec
26
comment Proof of shared secret through key derivation
@Reid I already said that "as long as you always use a constant size key and tag". Otherwise you can use HMAC, yes.
Dec
26
answered Proof of shared secret through key derivation
Dec
25
comment Keeping IV secret for AES CFB mode
@M.C.: What makes you think I think that CFB is not secure?
Dec
22
answered Keeping IV secret for AES CFB mode