Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Certificateless Proxy Re-Encryption Without Pairing: Revisited

Akshayaram Srinivasan, Chandrasekharan Pandu Rangan

Published Jan 1, 2015• 1 citation
OpenAlex

Abstract

Proxy Re-Encryption was introduced by Blaze, Bleumer and Strauss to efficiently solve the problem of delegation of decryption rights. In proxy re-encryption, a semi-honest proxy transforms a ciphertext intended for Alice to a ciphertext of the same message for Bob without learning anything about the underlying message. From its introduction, several proxy re-encryption schemes in the Public Key In-frastructure (PKI) and Identity (ID) based setting have been proposed. In practice, systems in the public key infrastructure suffer from the certificate management problem and those in identity based setting suffer from the key escrow problem. Certificateless Proxy Re-encryption schemes enjoy the advantages provided by ID-based constructions without suffering from the key escrow problem. In this work, we construct the first unidirectional, single-hop CCA-secure certificateless proxy re-encryption scheme without pairing by extending the PKI based construction of Chow et al. proposed in 2010. We prove its security in the random oracle model under the Computational Diffie-Hellman (CDH) assumption. Prior to this work, the only secure certificateless proxy re-encryption scheme is due to Guo et al. proposed in 2013 using bilinear pairing. The construction proposed in this work is more efficient than that system and its security relies on more standard assumptions. We also show that the recently proposed construction of Yang et al. is insecure with respect to the security model considered in this work.

Related papers

Toward CCA-secure bidirectional proxy re-encryption without pairing nor random oracle

Longxia Zhang, Xu An Wang, Wei Wang

Proxy re-encryption, introduced by Blaze et al. in 1998, allows a proxy to transform a ciphertext computed under Alice's public key into one that can be opened under Bob's decryption key. An open problem of constructing (bidirectional or unidirectional) IND-PRE-CCA2 secure proxy re-encryption scheme in the standard model yet without pairings was left until now. In this paper, based on Hanaoka's efficient chosen ciphertext secure public key encryption under the computational Diffie-Hellman assumption, we try to solve this open problem by presenting two new bidirectional proxy re-encryption schemes, which are restricted IND-PRE-CCA2 secure without pairing nor random oracle.

International Conference on Signal Processing Systems (ICSPS)•Jul 1, 2010•1 citation

Bidirectional proxy re-encryption schemes without pairing nor random oracle

Xu An Wang, Ping Wei, Weidong Zhong +1 more

Blaze et al. in 1998 introduced the concept of proxy re-encryption, which allows a proxy to transform a ciphertext computed under Alice's public key into one that can be opened under Bob's decryption key. In CCS'07, Canetti et al. proposed an IND-PRE-CCA2 bidirectional proxy re-encryption scheme, and later, Libert et al. proposed another IND-PRE-CCA2 secure unidirectional proxy re-encryption. However, both schemes rely on the costly bilinear pairings. In CANS'08, Deng et al. proposed the first IND-PRE-CCA2 secure proxy re-encryption without parings. Later, in PKC'09, Shao et al. proposed another IND-PRE-CCA2 secure proxy re-encryption without parings. But both of these schemes prove their security in the random oracle. In this paper, based on Hanaoka's efficient chosen ciphertext secure public key encryption under the computational Diffie-Hellman assumption, we present two new interesting bidirectional proxy re-encryption schemes, which are restricted IND-PRE-CCA2 secure without pairing nor random oracle.

•Jul 1, 2010•1 citation

CCA-secure Identity Based Proxy Re-encryption Based on a Variant of BB1 IBE

Xu An Wang, Xiaoyuan Yang, Junru Hu

In 1998, Blaze, Bleumer, and Strauss proposed a kind of cryptographic primitive called proxy re-encryption. In proxy re-encryption, a proxy can transform a ciphertext computed under Alice's public key into one that can be opened under Bob's decryption key. In this paper, with the help of the PKG, we construct a CCA-secure identity based proxy reencryption scheme based on a variant of BBi identity based encryption (IBE), we also prove its security in the random oracle model.

International Conference on Networks Security, Wireless Communications and Trusted Computing (NSWCTC)•Jan 1, 2010•2 citations

Identity Based Proxy Re-encryption From BB1 IBE

Jindan Zhang, Xu An Wang, Xiaoyuan Yang

In 1998, Blaze, Bleumer, and Strauss proposed a kind of cryptographic primitive called proxy re-encryption. In proxy re-encryption, a proxy can transform a ciphertext computed under Alice’s public key into one that can be opened under Bob’s decryption key. In 2007, Matsuo proposed the concept of four types of proxy re-encryption schemes: CBE (Certificate Based Public Key Encryption) to IBE (Identity Based Encryption) (type 1), IBE to IBE (type 2), IBE to CBE (type 3), CBE to CBE (type 4). In this paper, we find that if we allow the PKG to use its masterkey in the process of generating re-encryption key for proxy re-encryption in identity based setting, many open problems can be solved. We give the new security models for proxy reencryption in identity based setting, especially considering PKG’s involving in the re-encryption key generation process and PKG’s master-key’s security. We construct the new IND-ID-CPA and the first IND-ID-CCA2 secure proxy reencryption schemes based on BB1 IBE. We also prove their security by introducing some new techniques which maybe have independent interest. At last, we compare our new schemes with existing ones, the results show that our scheme can achieve high security levels and are very efficient for re-encryption and, which are very important for practical applications.

Journal of Computers•May 18, 2013•1 citation

A Fine-grained Certificateless Conditional Proxy Broadcast Re-Encryption Scheme Without Pairing

Hongfei Yang, Li Li, Chunyan Yang

Proxy re-encryption allows a semi-trusted proxy to convert the ciphertext of the data owner into the ciphertext of the target user. The certificateless proxy re-encryption eliminates the need for public key certificate in traditional public-key cryptography and key-escrow problem in identity-based cryptography, which makes it more convenient to apply. However, the existing certificateless proxy re-encryption schemes cannot support one-to-many conversion and flexible control on convert conditions. In this paper, we propose a fine-grained certificateless conditional proxy broadcast re-encryption scheme without pairing. In our scheme, the data owner can delegate the decryption rights of the ciphertext that meets certain conditions to the target users, and the data owner can revoke the delegate rights. At the same time, no pairing is used, which makes the scheme more efficient. Finally, we show that the security of the scheme for chosen-ciphertext attacks in the random oracle model.

IEEE Joint International Information Technology and Artificial Intelligence Conference (ITAIC)•Jun 17, 2022•8 citations

Restricted CCA-secure bidirectional proxy re-encryption scheme

Guo Duntao, Xu An Wang, Minqing Zhang +1 more

Proxy re-encryption allows a proxy to transform a ciphertext computed under Alice's public key into one that can be opened under Bob's decryption key. In CANS'08, Deng et al. proposed the first bidirectional IND-PRE-CCA2 secure proxy re-encryption without parings. Later, in PKC'09, Shao et al. proposed the first unidirectional IND-PRE-CCA2 secure proxy re-encryption without parings. But both of these schemes prove their security in the random oracle. They left an open problem of constructing (bidirectional or unidirectional) IND-PRE-CCA2 secure proxy re-encryption scheme in the standard model yet without pairings. In this paper, we try to solve this open problem by proposing two new restricted IND-PRE-CCA2 secure bidirectional proxy re-encryption schemes without pairing nor random oracle.

•Jul 1, 2010•0 citations
Proxy Re-Encryption was introduced by Blaze, Bleumer and Strauss to efficiently solve the problem of delegation of decryption rights. In proxy re-encryption, a semi-honest proxy transforms a ciphertext intended for Alice to a ciphertext of the same message for Bob without learning anything about the underlying message. From its introduction, several proxy re-encryption schemes in the Public Key In-frastructure (PKI) and Identity (ID) based setting have been proposed. In practice, systems in the public key infrastructure suffer from the certificate management problem and those in identity based setting suffer from the key escrow problem. Certificateless Proxy Re-encryption schemes enjoy the advantages provided by ID-based constructions without suffering from the key escrow problem. In this work, we construct the first unidirectional, single-hop CCA-secure certificateless proxy re-encryption scheme without pairing by extending the PKI based construction of Chow et al. proposed in 2010. We prove its security in the random oracle model under the Computational Diffie-Hellman (CDH) assumption. Prior to this work, the only secure certificateless proxy re-encryption scheme is due to Guo et al. proposed in 2013 using bilinear pairing. The construction proposed in this work is more efficient than that system and its security relies on more standard assumptions. We also show that the recently proposed construction of Yang et al. is insecure with respect to the security model considered in this work.
Proxy re-encryption, introduced by Blaze et al. in 1998, allows a proxy to transform a ciphertext computed under Alice's public key into one that can be opened under Bob's decryption key. An open problem of constructing (bidirectional or unidirectional) IND-PRE-CCA2 secure proxy re-encryption scheme in the standard model yet without pairings was left until now. In this paper, based on Hanaoka's efficient chosen ciphertext secure public key encryption under the computational Diffie-Hellman assumption, we try to solve this open problem by presenting two new bidirectional proxy re-encryption schemes, which are restricted IND-PRE-CCA2 secure without pairing nor random oracle.
Blaze et al. in 1998 introduced the concept of proxy re-encryption, which allows a proxy to transform a ciphertext computed under Alice's public key into one that can be opened under Bob's decryption key. In CCS'07, Canetti et al. proposed an IND-PRE-CCA2 bidirectional proxy re-encryption scheme, and later, Libert et al. proposed another IND-PRE-CCA2 secure unidirectional proxy re-encryption. However, both schemes rely on the costly bilinear pairings. In CANS'08, Deng et al. proposed the first IND-PRE-CCA2 secure proxy re-encryption without parings. Later, in PKC'09, Shao et al. proposed another IND-PRE-CCA2 secure proxy re-encryption without parings. But both of these schemes prove their security in the random oracle. In this paper, based on Hanaoka's efficient chosen ciphertext secure public key encryption under the computational Diffie-Hellman assumption, we present two new interesting bidirectional proxy re-encryption schemes, which are restricted IND-PRE-CCA2 secure without pairing nor random oracle.
In 1998, Blaze, Bleumer, and Strauss proposed a kind of cryptographic primitive called proxy re-encryption. In proxy re-encryption, a proxy can transform a ciphertext computed under Alice’s public key into one that can be opened under Bob’s decryption key. In 2007, Matsuo proposed the concept of four types of proxy re-encryption schemes: CBE (Certificate Based Public Key Encryption) to IBE (Identity Based Encryption) (type 1), IBE to IBE (type 2), IBE to CBE (type 3), CBE to CBE (type 4). In this paper, we find that if we allow the PKG to use its masterkey in the process of generating re-encryption key for proxy re-encryption in identity based setting, many open problems can be solved. We give the new security models for proxy reencryption in identity based setting, especially considering PKG’s involving in the re-encryption key generation process and PKG’s master-key’s security. We construct the new IND-ID-CPA and the first IND-ID-CCA2 secure proxy reencryption schemes based on BB1 IBE. We also prove their security by introducing some new techniques which maybe have independent interest. At last, we compare our new schemes with existing ones, the results show that our scheme can achieve high security levels and are very efficient for re-encryption and, which are very important for practical applications.
Proxy re-encryption allows a semi-trusted proxy to convert the ciphertext of the data owner into the ciphertext of the target user. The certificateless proxy re-encryption eliminates the need for public key certificate in traditional public-key cryptography and key-escrow problem in identity-based cryptography, which makes it more convenient to apply. However, the existing certificateless proxy re-encryption schemes cannot support one-to-many conversion and flexible control on convert conditions. In this paper, we propose a fine-grained certificateless conditional proxy broadcast re-encryption scheme without pairing. In our scheme, the data owner can delegate the decryption rights of the ciphertext that meets certain conditions to the target users, and the data owner can revoke the delegate rights. At the same time, no pairing is used, which makes the scheme more efficient. Finally, we show that the security of the scheme for chosen-ciphertext attacks in the random oracle model.
Proxy re-encryption allows a proxy to transform a ciphertext computed under Alice's public key into one that can be opened under Bob's decryption key. In CANS'08, Deng et al. proposed the first bidirectional IND-PRE-CCA2 secure proxy re-encryption without parings. Later, in PKC'09, Shao et al. proposed the first unidirectional IND-PRE-CCA2 secure proxy re-encryption without parings. But both of these schemes prove their security in the random oracle. They left an open problem of constructing (bidirectional or unidirectional) IND-PRE-CCA2 secure proxy re-encryption scheme in the standard model yet without pairings. In this paper, we try to solve this open problem by proposing two new restricted IND-PRE-CCA2 secure bidirectional proxy re-encryption schemes without pairing nor random oracle.