Description
The McEliece scheme is a generic framework allowing to use any error correcting code which disposes of an efficient decoding algorithm to design an encryption scheme by hiding a generator matrix of this code.
In the context of rank metric, we propose a generalization of the McEliece frame to matrix codes. From a vector code, we compute a matrix version of this code, that is hidden in such a way that the code obtained is indistinguishable from a random code. We propose to mask the linearity of the vector code on the extension, which implies a bigger public key (since the code is less structured) but allows to allows to keep a very small size of ciphertext. It results in an encryption scheme whose security relies on a generic instance of the MinRank problem, known to be NP-complete.
Applying it with Gabidulin codes, our approach gives a better trade-off between ciphertexts and public keys sizes than the classic McEliece scheme. For 128 bits of security, we propose parameters with ciphertext of size 65B and public key of size 98kB.
Travail en commun avec Nicolas Aragon, Alain Couvreur, Victor Dyseryn, Philippe Gaborit
Infos pratiques
Prochains exposés
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Cryptography
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Symmetrical primitive
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Implementation of cryptographic algorithm
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Algorithms for post-quantum commutative group actions
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At the historical foundation of isogeny-based cryptography lies a scheme known as CRS; a key exchange protocol based on class group actions on elliptic curves. Along with more efficient variants, such as CSIDH, this framework has emerged as a powerful building block for the construction of advanced post-quantum cryptographic primitives. Unfortunately, all protocols in this line of work are[…] -
Endomorphisms via Splittings
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One of the fundamental hardness assumptions underlying isogeny-based cryptography is the problem of finding a non-trivial endomorphism of a given supersingular elliptic curve. In this talk, we show that the problem is related to the problem of finding a splitting of a principally polarised superspecial abelian surface. In particular, we provide formal security reductions and a proof-of-concept[…]-
Cryptography
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