References of "Seurin, Yannick"
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See detailNew Constructions of MACs from (Tweakable) Block Ciphers
Cogliati, Benoît-Michel UL; Lee, Jooyoung; Seurin, Yannick

in IACR Transactions on Symmetric Cryptology (2017)

We propose new constructions of Message Authentication Codes (MACs) from tweakable or conventional block ciphers. Our new schemes are either stateless and deterministic, nonce-based, or randomized, and ... [more ▼]

We propose new constructions of Message Authentication Codes (MACs) from tweakable or conventional block ciphers. Our new schemes are either stateless and deterministic, nonce-based, or randomized, and provably secure either in the standard model for tweakable block cipher-based ones, or in the ideal cipher model for block cipher-based ones. All our constructions are very efficient, requiring only one call to the underlying (tweakable) block cipher in addition to universally hashing the message. Moreover, the security bounds we obtain are quite strong: they are beyond the birthday bound, and nonce-based/randomized variants provide graceful security degradation in case of misuse, i.e., the security bound degrades linearly with the maximal number of repetitions of nonces/random values. [less ▲]

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See detailA Domain Extender for the Ideal Cipher
Coron, Jean-Sébastien UL; Dodis, Yevgeniy; Mandal, Avradip UL et al

in Proceedings of TCC 2010 (2010)

We describe the first domain extender for ideal ciphers, i.e. we show a construction that is indifferentiable from a 2n-bit ideal cipher, given a n-bit ideal cipher. Our construction is based on a 3-round ... [more ▼]

We describe the first domain extender for ideal ciphers, i.e. we show a construction that is indifferentiable from a 2n-bit ideal cipher, given a n-bit ideal cipher. Our construction is based on a 3-round Feistel, and is more efficient than first building a n-bit random oracle from a n-bit ideal cipher (as in [9]) and then a 2n-bit ideal cipher from a n-bit random oracle (as in [10], using a 6-round Feistel). We also show that 2 rounds are not enough for indifferentiability by exhibiting a simple attack. We also consider our construction in the standard model: we show that 2 rounds are enough to get a 2n-bit tweakable block-cipher from a n-bit tweakable block-cipher and we show that with 3 rounds we can get beyond the birthday security bound. [less ▲]

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See detailThe Random Oracle Model and the Ideal Cipher Model Are Equivalent
Coron, Jean-Sébastien UL; Patarin, Jacques; Seurin, Yannick

in Advances in Cryptography (2008)

Detailed reference viewed: 77 (3 UL)