Ecole normale superieure

Displaying 1-8 of 8 results

  • White Papers // Feb 2012

    Round-Optimal Privacy-Preserving Protocols With Smooth Projective Hash Functions

    In 2008, Groth and Sahai proposed a powerful suite of techniques for constructing non-interactive zero-knowledge proofs in bilinear groups. Their proof systems have found numerous applications, including group signature schemes, anonymous voting, and anonymous credentials. In this paper, the authors demonstrate that the notion of smooth projective hash functions can...

    Provided By Ecole normale superieure

  • White Papers // May 2011

    Practical Key-Recovery for All Possible Parameters of SFLASH

    In this paper, the authors present a new practical key-recovery attack on the SFLASH signature scheme. SFLASH is a derivative of the older C encryption and signature scheme that was broken in 1995 by Patarin. In SFLASH, the public key is truncated, and this simple countermeasure prevents Patarin's attack. The...

    Provided By Ecole normale superieure

  • White Papers // Dec 2010

    Differential Attack on Five Rounds of the SC2000 Block Cipher

    SC2000 is a 128-bit block cipher with a user key of 128, 192 or 256 bits, which employs a total of 6.5 rounds for a 128-bit user key, and a total of 7.5 rounds for a 192 or 256-bit key. It was designed to "Have high performance on a wide...

    Provided By Ecole normale superieure

  • White Papers // Jun 2010

    Security Analysis of SIMD

    In this paper the authors study the security of the SHA-3 candidate SIMD. They first show a new free-start distinguisher based on symmetry relations. It allows distinguishing the compression function of SIMD from a random function with a single evaluation. However, they also show that this property is very hard...

    Provided By Ecole normale superieure

  • White Papers // Oct 2009

    Fault Attacks Against EMV Signatures

    At CHES 2009, Coron, Joux, Kizhvatov, Naccache and Paillier (CJKNP) exhibited a fault attack against RSA signatures with partially known messages. This attack allows factoring the public modulus N. While the size of the Unknown Message Part (UMP) increases with the number of faulty signatures available, the complexity of cjknp's...

    Provided By Ecole normale superieure

  • White Papers // Dec 2008

    Encrypting Proofs on Pairings and Its Application to Anonymity for Signatures

    The authors give a generic methodology to unlinkably anonymize cryptographic schemes in bilinear groups using the Boneh-Goh-Nissim cryptosystem and nizk proofs in the line of Groth, Ostrovsky and Sahai. They illustrate the techniques by presenting the first instantiation of anonymous proxy signatures, a recent primitive unifying the functionalities and strong...

    Provided By Ecole normale superieure

  • White Papers // Oct 2008

    Divisibility, Smoothness and Cryptographic Applications

    This paper deals with products of moderate-size primes, familiarly known as smooth numbers. Smooth numbers play a crucial role in information theory, signal processing and cryptography. The authors present various properties of smooth numbers relating to their enumeration, distribution and occurrence in various integer sequences. They then turn the attention...

    Provided By Ecole normale superieure

  • White Papers // Sep 2008

    New Anonymity Notions for Identity-Based Encryption

    Identity-based encryption is a very convenient tool to avoid key management. Recipient-privacy is also a major concern nowadays. To combine both, anonymous identity-based encryption has been proposed. This paper extends this notion to stronger adversaries (the authority itself). The authors discuss this new notion, together with a new kind of...

    Provided By Ecole normale superieure

  • White Papers // Jun 2010

    Security Analysis of SIMD

    In this paper the authors study the security of the SHA-3 candidate SIMD. They first show a new free-start distinguisher based on symmetry relations. It allows distinguishing the compression function of SIMD from a random function with a single evaluation. However, they also show that this property is very hard...

    Provided By Ecole normale superieure

  • White Papers // Dec 2010

    Differential Attack on Five Rounds of the SC2000 Block Cipher

    SC2000 is a 128-bit block cipher with a user key of 128, 192 or 256 bits, which employs a total of 6.5 rounds for a 128-bit user key, and a total of 7.5 rounds for a 192 or 256-bit key. It was designed to "Have high performance on a wide...

    Provided By Ecole normale superieure

  • White Papers // Oct 2009

    Fault Attacks Against EMV Signatures

    At CHES 2009, Coron, Joux, Kizhvatov, Naccache and Paillier (CJKNP) exhibited a fault attack against RSA signatures with partially known messages. This attack allows factoring the public modulus N. While the size of the Unknown Message Part (UMP) increases with the number of faulty signatures available, the complexity of cjknp's...

    Provided By Ecole normale superieure

  • White Papers // Oct 2008

    Divisibility, Smoothness and Cryptographic Applications

    This paper deals with products of moderate-size primes, familiarly known as smooth numbers. Smooth numbers play a crucial role in information theory, signal processing and cryptography. The authors present various properties of smooth numbers relating to their enumeration, distribution and occurrence in various integer sequences. They then turn the attention...

    Provided By Ecole normale superieure

  • White Papers // Dec 2008

    Encrypting Proofs on Pairings and Its Application to Anonymity for Signatures

    The authors give a generic methodology to unlinkably anonymize cryptographic schemes in bilinear groups using the Boneh-Goh-Nissim cryptosystem and nizk proofs in the line of Groth, Ostrovsky and Sahai. They illustrate the techniques by presenting the first instantiation of anonymous proxy signatures, a recent primitive unifying the functionalities and strong...

    Provided By Ecole normale superieure

  • White Papers // May 2011

    Practical Key-Recovery for All Possible Parameters of SFLASH

    In this paper, the authors present a new practical key-recovery attack on the SFLASH signature scheme. SFLASH is a derivative of the older C encryption and signature scheme that was broken in 1995 by Patarin. In SFLASH, the public key is truncated, and this simple countermeasure prevents Patarin's attack. The...

    Provided By Ecole normale superieure

  • White Papers // Sep 2008

    New Anonymity Notions for Identity-Based Encryption

    Identity-based encryption is a very convenient tool to avoid key management. Recipient-privacy is also a major concern nowadays. To combine both, anonymous identity-based encryption has been proposed. This paper extends this notion to stronger adversaries (the authority itself). The authors discuss this new notion, together with a new kind of...

    Provided By Ecole normale superieure

  • White Papers // Feb 2012

    Round-Optimal Privacy-Preserving Protocols With Smooth Projective Hash Functions

    In 2008, Groth and Sahai proposed a powerful suite of techniques for constructing non-interactive zero-knowledge proofs in bilinear groups. Their proof systems have found numerous applications, including group signature schemes, anonymous voting, and anonymous credentials. In this paper, the authors demonstrate that the notion of smooth projective hash functions can...

    Provided By Ecole normale superieure