1,416 reputation
618
bio website
location
age
visits member for 3 years
seen 4 hours ago

Working in industry as a cryptography engineer.

To contact me, email paulgrub AT umail DOT iu DOT edu


Nov
18
comment Java RSA/ECB/PKCS1Padding encryption with .NET
This question appears to be off-topic because it is about a specific cryptography library.
Nov
14
comment As a cryptographer, what are the things I should care about in my implementation of pairing functions?
In my opinion the question is too open-ended. You should ask specific questions about specific aspects of pairing implementations. Also pairings are a new and complex primitive that are still pretty niche. Also, you could ask the author of PBC this in an email.
Nov
10
comment What is the most computationally efficient way of generating pseudo-random permutations?
FFX and the oblivious card shuffles have identical use cases. They are both used in the same way to efficiently generate PRPs for arbitrary sets.
Nov
9
comment As a cryptographer, what are the things I should care about in my implementation of pairing functions?
On number 2, can you give a citation? I know there has been work that broke the DL problem for finite fields of small characteristic, but that work doesn't apply to ECDLP.
Nov
6
comment What is the most computationally efficient way of generating pseudo-random permutations?
In terms of the number of AES calls needed to encrypt a value, it would be more expensive. For your purposes the speed difference would probably not be significant, especially if you use AES-NI.
Oct
31
comment RSA Decryption given n, e, and phi(n)
Well, do you understand how RSA encryption and decryption work?
Oct
29
comment What are SNARKs?
eprint.iacr.org/2013/879 The citations from this should get you started.
Oct
23
comment Format Preserving Encryption for 32 or 64 bit plaintext values
I seriously doubt Voltage's patent covers as much as they say it does. Anyway, for small blocks you could use any of the FPE schemes based on oblivious card shuffles, e.g. the Thorp shuffle.
Oct
23
comment Format Preserving Encryption for 32 or 64 bit plaintext values
Also, to the OP: There are plenty of other schemes which achieve FPE that are not patented. Look (for example) at the BPS mode of operation, the spec of which is on the NIST modes development page.
Oct
23
comment Format Preserving Encryption for 32 or 64 bit plaintext values
Please, for the love of god do not make custom modifications to AES when there are other solutions that could work perfectly fine.
Oct
17
comment Prove that the affine cipher over Z26 has perfect secrecy if every key is used with equal probability of 1/312
Well, I'd start by reviewing the definition of perfect secrecy.
Oct
8
comment How costly is to find millions of large prime numbers for RSA?
OP: Are you implementing a Honey Encryption scheme for RSA secret keys?
Sep
30
comment Bridging the gap between security proofs and “real-world” security
Hmm... you might be right. I wouldn't be offended if people voted to close; this was just on my mind and I wanted to solicit input from the community.
Sep
30
comment Bridging the gap between security proofs and “real-world” security
I guess a salient example of this is encryption that preserves some functionality of the plaintext in the ciphertexts. Most good schemes in this area provide a proof of security based on a constructed model of the ideal functionality. How do we reason about the relevance of that model to a real deployed implementation of the scheme?
Sep
24
comment what is the difference between IBE and ABE schemes
This sounds like a homework question. Is it?
Sep
24
comment reducing false positives in searchable encryption
Actually I'm not sure, come to think of it.
Sep
23
comment reducing false positives in searchable encryption
D.W. is (i think) his handle here.
Sep
22
comment Checking the share membership in secret sharing schemes
I suspect this kind of distinguishing ability would break the information-theoretic security of the Shamir scheme, but I'm not sure.
Sep
19
comment reducing false positives in searchable encryption
David Wagner is a member of this community... Hopefully he'll see this and give you an authoritative answer :)
Sep
17
comment Secure order preserving hash function
To the OP: It's also possible to construct an order-preserving compression algorithm for strings: 1 2