6 results sorted by ID
Possible spell-corrected query: M-side
Pairing Optimizations for Isogeny-based Cryptosystems
Shiping Cai, Kaizhan Lin, Chang-An Zhao
Implementation
In isogeny-based cryptography, bilinear pairings are regarded as a powerful tool in various applications, including key compression, public-key validation and torsion basis generation. However, in most isogeny-based protocols, the performance of pairing computations is unsatisfactory due to the high computational cost of the Miller function. Reducing the computational expense of the Miller function is crucial for enhancing the overall performance of pairing computations in isogeny-based...
SILBE: an Updatable Public Key Encryption Scheme from Lollipop Attacks
Max Duparc, Tako Boris Fouotsa, Serge Vaudenay
Public-key cryptography
We present a new post-quantum Public Key Encryption scheme (PKE) named Supersingular Isogeny Lollipop Based Encryption or SILBE. SILBE is obtained by leveraging the generalised lollipop attack of Castryck and Vercauteren on the M-SIDH Key exchange by Fouotsa, Moriya and Petit.
Doing so, we can in fact make SILBE a post-quantum secure Updatable Public Key Encryption scheme (UPKE). SILBE is in fact the first isogeny-based UPKE which is not based on group actions. Hence, SILBE overcomes the...
Zero-Knowledge Proofs for SIDH variants with Masked Degree or Torsion
Youcef Mokrani, David Jao
Public-key cryptography
The polynomial attacks on SIDH by Castryck, Decru, Maino, Martindale and Robert have shown that, while the general isogeny problem is still considered unfeasible to break, it is possible to efficiently compute a secret isogeny when given its degree and image on enough torsion points.
A natural response from many researchers has been to propose SIDH variants where one or both of these possible extra pieces of information is masked in order to obtain schemes for which a polynomial attack is...
A polynomial-time attack on instances of M-SIDH and FESTA
Wouter Castryck, Frederik Vercauteren
Public-key cryptography
The recent devastating attacks on SIDH rely on the fact that the protocol reveals the images $\varphi(P)$ and $\varphi(Q)$ of the secret isogeny $\varphi : E_0 \rightarrow E$ on a basis $\{P, Q\}$ of the $N$-torsion subgroup $E_0[N]$ where $N^2 > \deg(\varphi)$. To thwart this attack, two recent proposals, M-SIDH and FESTA, proceed by only revealing the images upto unknown scalars $\lambda_1, \lambda_2 \in \mathbb{Z}_N^\times$, i.e., only $\lambda_1 \varphi(P)$ and $\lambda_2 \varphi(Q)$...
Compressed M-SIDH: An Instance of Compressed SIDH-like Schemes with Isogenies of Highly Composite Degrees
Kaizhan Lin, Jianming Lin, Shiping Cai, Weize Wang, Chang-An Zhao
Public-key cryptography
Recently, SIDH was broken by a series of attacks. To avoid the attacks, several new countermeasures, such as M-SIDH and binSIDH, have been developed. Different from SIDH, the new SIDH-like schemes have relatively large public key sizes. Besides, the orders of the torsion groups considered in new SIDH-like schemes are the products of many primes. Therefore, the key compression techniques in SIDH can not be directly applied to these schemes. It remains an open problem to compress the public...
M-SIDH and MD-SIDH: countering SIDH attacks by masking information
Tako Boris Fouotsa, Tomoki Moriya, Christophe Petit
Public-key cryptography
The SIDH protocol is an isogeny-based key exchange protocol using supersingular isogenies, designed by Jao and De Feo in 2011.
The protocol underlies the SIKE algorithm which advanced to the fourth round of NIST's post-quantum standardization project in May 2022.
The algorithm was considered very promising: indeed the most significant attacks against SIDH were meet-in-the-middle variants with exponential complexity, and torsion point attacks which only applied to unbalanced parameters...
In isogeny-based cryptography, bilinear pairings are regarded as a powerful tool in various applications, including key compression, public-key validation and torsion basis generation. However, in most isogeny-based protocols, the performance of pairing computations is unsatisfactory due to the high computational cost of the Miller function. Reducing the computational expense of the Miller function is crucial for enhancing the overall performance of pairing computations in isogeny-based...
We present a new post-quantum Public Key Encryption scheme (PKE) named Supersingular Isogeny Lollipop Based Encryption or SILBE. SILBE is obtained by leveraging the generalised lollipop attack of Castryck and Vercauteren on the M-SIDH Key exchange by Fouotsa, Moriya and Petit. Doing so, we can in fact make SILBE a post-quantum secure Updatable Public Key Encryption scheme (UPKE). SILBE is in fact the first isogeny-based UPKE which is not based on group actions. Hence, SILBE overcomes the...
The polynomial attacks on SIDH by Castryck, Decru, Maino, Martindale and Robert have shown that, while the general isogeny problem is still considered unfeasible to break, it is possible to efficiently compute a secret isogeny when given its degree and image on enough torsion points. A natural response from many researchers has been to propose SIDH variants where one or both of these possible extra pieces of information is masked in order to obtain schemes for which a polynomial attack is...
The recent devastating attacks on SIDH rely on the fact that the protocol reveals the images $\varphi(P)$ and $\varphi(Q)$ of the secret isogeny $\varphi : E_0 \rightarrow E$ on a basis $\{P, Q\}$ of the $N$-torsion subgroup $E_0[N]$ where $N^2 > \deg(\varphi)$. To thwart this attack, two recent proposals, M-SIDH and FESTA, proceed by only revealing the images upto unknown scalars $\lambda_1, \lambda_2 \in \mathbb{Z}_N^\times$, i.e., only $\lambda_1 \varphi(P)$ and $\lambda_2 \varphi(Q)$...
Recently, SIDH was broken by a series of attacks. To avoid the attacks, several new countermeasures, such as M-SIDH and binSIDH, have been developed. Different from SIDH, the new SIDH-like schemes have relatively large public key sizes. Besides, the orders of the torsion groups considered in new SIDH-like schemes are the products of many primes. Therefore, the key compression techniques in SIDH can not be directly applied to these schemes. It remains an open problem to compress the public...
The SIDH protocol is an isogeny-based key exchange protocol using supersingular isogenies, designed by Jao and De Feo in 2011. The protocol underlies the SIKE algorithm which advanced to the fourth round of NIST's post-quantum standardization project in May 2022. The algorithm was considered very promising: indeed the most significant attacks against SIDH were meet-in-the-middle variants with exponential complexity, and torsion point attacks which only applied to unbalanced parameters...
