Notice
5.6. An Efficient Provably Secure One-Way Function
- document 1 document 2 document 3
- niveau 1 niveau 2 niveau 3
Descriptif
In this session, we aregoing to see how to build an efficient provably secureone-way function from coding theory. As you know, a one-wayfunction is a function which is simple to evaluate andwhich should be as fast as possible and hard to invert,ideally with good security arguments. There are manyapplications of one-way functions, especially in symmetriccryptography. For example, for compression functions tobuild hash functions, expansion functions to build pseudorandomnumber generators but many more. Unfortunately, one-wayfunctions are hard to build. We know some very fastfunctions which have very few security arguments and wehave some very strong security arguments forfunctions which are very slow. What we will try to do is toget a fast and secure function. Niederreiter Encryption is agood candidate for one-way function. Any public key encryptionscheme is a one-way function with a trapdoor, whichis the decryption key. It has very strong securityarguments usually a proof of security. But public keyencryption is usually very slow, especially if you takeconstruction from numbers theory, you require an expentiationwhich is expensive to compute. Niederreiter Encryption is muchfaster than other public key schemes. It simply converts theinput into a low weight word. There are many differenttechniques to do this and then compute its syndrome whichis only a few XORs, especially if the weight is very small. The trapdoor can be easilyremoved by simply using a random binary matrix whichis enough when we don't need to invert this one-way function. And with a few tweaks, itcan be made even faster than the usual Niederreiter Encryption. Here, we will give an overview ofthe one-way function we are building. The parameters are matrix Hof size r*n and the constant weight encoding function φwhich takes l bits and output a word of weight w and length n. The one-way function simplytakes an input x and computes φ(x) and multiplies it byH to obtain a value, a syndrome y. Security ofthis function: inverting the function requires tosolve an instance of syndrome decoding; and efficiency:if φ is fast and w is small, then the functioncan be very efficient.
Intervention
Dans la même collection
-
5.7. The Fast Syndrome-Based (FSB) Hash Function
Marquez-CorbellaIreneSendrierNicolasFiniaszMatthieuIn the last session of this week, we will have a look at the FSB Hash Function which is built using the one-way function we saw in the previous session. What are the requirements for a
-
5.1. Code-Based Digital Signatures
Marquez-CorbellaIreneSendrierNicolasFiniaszMatthieuWelcome to the last week of this MOOC on code-based cryptography. This week, we will be discussing other cryptographic constructions relying on coding theory. We have seen how to do public key
-
5.4. Parallel-CFS
Marquez-CorbellaIreneSendrierNicolasFiniaszMatthieuIn this session, I will present a variant of the CFS signature scheme called parallel-CFS. We start from a simple question: what happens if you try to use two different hash functions and compute
-
5.2. The Courtois-Finiasz-Sendrier (CFS) Construction
Marquez-CorbellaIreneSendrierNicolasFiniaszMatthieuIn this session, I am going to present the Courtois-Finiasz-Sendrier Construction of a code-based digital signature. In the previous session, we have seen that it is impossible to hash a document
-
5.5. Stern’s Zero-Knowledge Identification Scheme
Marquez-CorbellaIreneSendrierNicolasFiniaszMatthieuIn this session, we are going to have a look at Stern’s Zero-Knowledge Identification Scheme. So, what is a Zero-Knowledge Identification Scheme? An identification scheme allows a prover to prove
-
5.3. Attacks against the CFS Scheme
Marquez-CorbellaIreneSendrierNicolasFiniaszMatthieuIn this session, we will have a look at the attacks against the CFS signature scheme. As for public-key encryption, there are two kinds of attacks against signature schemes. First kind of attack is
Avec les mêmes intervenants et intervenantes
-
5.1. Code-Based Digital Signatures
Marquez-CorbellaIreneSendrierNicolasFiniaszMatthieuWelcome to the last week of this MOOC on code-based cryptography. This week, we will be discussing other cryptographic constructions relying on coding theory. We have seen how to do public key
-
4.5. Error-Correcting Pairs
Marquez-CorbellaIreneSendrierNicolasFiniaszMatthieuWe present in this session a general decoding method for linear codes. And we will see it in an example. Let C be a generalized Reed-Solomon code of dimension k associated to the pair (c, d). Then,
-
5.4. Parallel-CFS
Marquez-CorbellaIreneSendrierNicolasFiniaszMatthieuIn this session, I will present a variant of the CFS signature scheme called parallel-CFS. We start from a simple question: what happens if you try to use two different hash functions and compute
-
4.8. Attack against Algebraic Geometry codes
Marquez-CorbellaIreneSendrierNicolasFiniaszMatthieuIn this session, we will present an attack against Algebraic Geometry codes (AG codes). Algebraic Geometry codes is determined by a triple. First of all, an algebraic curve of genus g, then a n
-
5.2. The Courtois-Finiasz-Sendrier (CFS) Construction
Marquez-CorbellaIreneSendrierNicolasFiniaszMatthieuIn this session, I am going to present the Courtois-Finiasz-Sendrier Construction of a code-based digital signature. In the previous session, we have seen that it is impossible to hash a document
-
4.6. Attack against GRS codes
Marquez-CorbellaIreneSendrierNicolasFiniaszMatthieuIn this session we will discuss the proposal of using generalized Reed-Solomon codes for the McEliece cryptosystem. As we have already said, generalized Reed-Solomon codes were proposed in 1986 by
-
5.5. Stern’s Zero-Knowledge Identification Scheme
Marquez-CorbellaIreneSendrierNicolasFiniaszMatthieuIn this session, we are going to have a look at Stern’s Zero-Knowledge Identification Scheme. So, what is a Zero-Knowledge Identification Scheme? An identification scheme allows a prover to prove
-
4.9. Goppa codes still resist
Marquez-CorbellaIreneSendrierNicolasFiniaszMatthieuAll the results that we have seen this week doesn't mean that code based cryptography is broken. So in this session we will see that Goppa code still resists to all these attacks. So recall that
-
4.4. Attack against subcodes of GRS codes
Marquez-CorbellaIreneSendrierNicolasFiniaszMatthieuIn this session, we will talk about using subcodes of a Generalized Reed–Solomon code for the McEliece Cryptosystem. Recall that to avoid the attack of Sidelnikov and Shestakov, Berger and
-
5.3. Attacks against the CFS Scheme
Marquez-CorbellaIreneSendrierNicolasFiniaszMatthieuIn this session, we will have a look at the attacks against the CFS signature scheme. As for public-key encryption, there are two kinds of attacks against signature schemes. First kind of attack is
-
4.7. Attack against Reed-Muller codes
Marquez-CorbellaIreneSendrierNicolasFiniaszMatthieuIn this session, we will introduce an attack against binary Reed-Muller codes. Reed-Muller codes were introduced by Muller in 1954 and, later, Reed provided the first efficient decoding algorithm
-
5.7. The Fast Syndrome-Based (FSB) Hash Function
Marquez-CorbellaIreneSendrierNicolasFiniaszMatthieuIn the last session of this week, we will have a look at the FSB Hash Function which is built using the one-way function we saw in the previous session. What are the requirements for a
Sur le même thème
-
Quel est le prix à payer pour la sécurité de nos données ?
MinaudBriceÀ l'ère du tout connecté, la question de la sécurité de nos données personnelles est devenue primordiale. Comment faire pour garder le contrôle de nos données ? Comment déjouer les pièges de plus en
-
Des systèmes de numération pour le calcul modulaire
BajardJean-ClaudeLe calcul modulaire est utilisé dans de nombreuses applications des mathématiques, telles que la cryptographie. La réduction modulaire dans un contexte très général est coûteuse, car elle n
-
Projection methods for community detection in complex networks
LitvakNellyCommunity detection is one of most prominent tasks in the analysis of complex networks such as social networks, biological networks, and the world wide web. A community is loosely defined as a group
-
Lara Croft. doing fieldwork under surveillance
Dall'AgnolaJasminLara Croft. Doing Fieldwork Under Surveillance Intervention de Jasmin Dall'Agnola (The George Washington University), dans le cadre du Colloque coorganisé par Anders Albrechtslund, professeur en
-
Containing predictive tokens in the EU
CzarnockiJanContaining Predictive Tokens in the EU – Mapping the Laws Against Digital Surveillance, intervention de Jan Czarnocki (KU Leuven), dans le cadre du Colloque coorganisé par Anders Albrechtslund,
-
Inauguration de l'exposition - Vanessa Vitse : Nombres de Sophie Germain et codes secrets
VitseVanessaExposé de Vanessa Vitse (Institut Fourier) : Nombres de Sophie Germain et codes secrets
-
"Le mathématicien Petre (Pierre) Sergescu, historien des sciences, personnalité du XXe siècle"
HerléaAlexandreAlexandre HERLEA est membre de la section « Sciences, histoire des sciences et des techniques et archéologie industrielle » du CTHS. Professeur émérite des universités, membre effectif de l'Académie
-
Ivan Murit - Processus de création d'images
MuritIvanJe vais présenter une manière décalée d'aborder les outils d'impression. Pour cela nous ne partirons pas de l'envie d'imprimer une image préexistante, mais d'avant cela : comment se crée une forme
-
Retour d'expérience sur l'utilisation croisée de plusieurs archives de fouilles
TufféryChristopheDans le cadre d'une thèse de doctorat engagée depuis 2019, une étude historiographique et épistémologique des effets des dispositifs numériques sur l'archéologie et sur les archéologues au cours des
-
Information Structures for Privacy and Fairness
PalamidessiCatusciaInformation Structures for Privacy and Fairness
-
Le Creativ’Lab, au cœur de la robotique et de l’intelligence artificielle (ASR N°18 - LORIA)
HénaffPatrickLefebvreSylvainLe LORIA, laboratoire phare de la Grande Région dans le domaine de l’informatique, propose de rendre la recherche plus ouverte, plus collaborative, plus ambitieuse… en un mot, plus créative, à travers
-
AI and Human Decision-Making: An Interdisciplinary Perspective
CastellucciaClaudeThis seminar will talk about some of the privacy risks of these systems and will describe some recent attacks. It will also discuss why they sometimes fail to deliver. Finally, we will also show that