Paolo Santini
LightNews LightNews
palli-santini.bsky.social
Paolo Santini
@palli-santini.bsky.social
25 followers 31 following 2 posts
Trying to be a guitarist, a runner and a good person. Sometimes, I also do cryptography
Posts Replies Media Videos
palli-santini.bsky.social
Reducing LESS public key size! Can we make it even shorter? 🤔

Big thanks to Marco Baldi, Riccardo Schiavoni and @rahmec.bsky.social
eprint.ing.bot ePrint Updates @eprint.ing.bot · 3d
On the representation of self-orthogonal codes and applications to cryptography (Marco Baldi, Rahmi El Mechri, Paolo Santini, Riccardo Schiavoni) ia.cr/2025/2279
Abstract. The of a linear code is the intersection between the code and its dual. When the hull is equal to the code (i.e., the code is contained in the dual), the code is called (or ); if, moreover, the code is equal to its dual, then we speak of a code. For problems such as the Permutation Equivalence Problem (PEP) and (special instances of) the Lattice Isomorphism Problem (LIP) over q-ary lattices, codes with a sufficiently large hull provide hard-to-solve instances. In this paper we describe a technique to compress the representation of a self-orthogonal code. Namely, we propose an efficient compression (and decompression) technique that allows representing the generator matrix of a self-orthogonal code with slightly more than $k(n-k)-\binom{k+1}{2}$ finite field elements. The rationale consists in exploiting the relationships deriving from self-orthogonality to reconstruct part of the generator matrix entries from the others, thus reducing the amount of entries one needs to uniquely represent the code. For instance, for self-dual codes, this almost halves the amount of finite field elements required to represent the code. We first present a basic version of our algorithm and show that it runs in polynomial time and, moreover, its communication cost asymptotically approaches the lower bound set by Shannon’s source coding theorem. Then, we provide an improved version which reduces both the size of the representation and the time complexity, essentially making the representation technique as costly as Gaussian elimination. %Under plausible heuristic assumptions (which we have verified via intensive numerical simulations), we furthermore show that our encoding technique is asymptotically optimal (in the sense that the amount of required information bits matches with the theoretical lower bound from Shannon’s theorem). As concrete applications, we show that our technique can be used to reduce the public key size in cryptosystems based on PEP such as LESS and SPECK (achieving approximately a 50% reduction in the public key size), as well as in the Updatable Public Key Encryption Scheme recently proposed by Albrecht, Benčina and Lai, which is based on LIP. Image showing part 2 of abstract. Image showing part 3 of abstract.
December 22, 2025 at 5:28 PM
Reposted by Paolo Santini
signal.org
We are alarmed by reports that Germany is on the verge of a catastrophic about-face, reversing its longstanding and principled opposition to the EU’s Chat Control proposal which, if passed, could spell the end of the right to privacy in Europe. signal.org/blog/pdfs/ge...
signal.org
October 3, 2025 at 4:14 PM
Reposted by Paolo Santini
tiborj.bsky.social
The call for papers for PKC 2026 is out: pkc.iacr.org/2026/callfor...
PKC 2026 call for papers
Public Key Cryptography
pkc.iacr.org
September 25, 2025 at 5:53 PM
palli-santini.bsky.social
So happy to have been a speaker for the "4th Training school on wireless & cyber-physical system security" held in Technical University of Braunschweig. Wonderful city, wonderful people and wonderful event! Thanks a lot for the invitation 😀
@tu-braunschweig.de
@6g-physec.bsky.social
September 19, 2025 at 5:35 PM
Reposted by Paolo Santini
dfaranha.bsky.social
The EU wants to spend your money to assemble a giant mass surveillance machine with little effect on harm against children. Chat Control is not effective, weakens security for all and does not respect privacy. Contact your EU representatives and let them know.

csa-scientist-open-letter.org/Sep2025
csa-scientist-open-letter.org
September 9, 2025 at 11:24 AM