可扩展可撤销无证书加密：抵御解密密钥暴露

84 浏览量更新于2024-08-26 收藏 187KB PDF 举报

"无证书公共密钥密码系统（CLPKC）是一种旨在解决传统基于证书的公钥加密体系中密钥托管问题的加密技术。CLPKC允许用户直接使用他们的身份作为公钥，无需第三方机构颁发和管理证书。然而，CLPKC中的一个关键挑战是如何有效地处理密钥吊销，尤其是当解密密钥被泄露时。现有的撤销策略要么效率低下，要么存在安全隐患。在该研究论文中，作者提出了第一个可扩展可撤销的无证书加密（RCLE）方案，该方案专门针对解密密钥暴露的问题。这个创新的RCLE方案在标准模型下被证明是安全的，这意味着它不受已知攻击的威胁，并且能够在实际环境中提供可靠的保障。通过设计这样的系统，即使解密密钥被非法获取，也能迅速有效地撤销，保护数据的安全性。此外，作者还提出了一种新的RCLE方案，其特点是解密密钥长度极短。这不仅提高了系统的效率，也降低了存储和管理密钥的复杂性。短密钥的优势在于减少了计算资源的需求，使得加密和解密过程更快，同时保持了安全性。该研究发表在《IET Information Security》期刊上，经过多次修订和审阅，最终于2014年7月31日被接受发表。作者包括来自南京师范大学计算机科学与技术学院、江苏省信息安全与隐私保护技术工程研究中心的学者，以及新加坡管理大学信息系统学院的专家。研究团队通过电子邮件bela_suno@163.com进行联系。这篇论文的贡献在于提供了对CLPKC中撤销机制的改进，为未来无证书加密系统的设计提供了新的思路和方法，特别是在处理解密密钥暴露的情况下。这一进展对于增强网络安全，尤其是在大数据和云计算环境中，保护敏感信息免受未经授权访问的重要性不言而喻。"

Published in IET Information Security

Received on 18th September 2013

Revised on 29th July 2014

Accepted on 31st July 2014

doi: 10.1049/iet-ifs.2014.0145

ISSN 1751-8709

Efficient revocable certificateless encryption against

decryption key exposure

Yinxia Sun

1,2

, Futai Zhang

1,2

, Limin Shen

1,2

, Robert H. Deng

School of Computer Science and Technology, Nanjing Normal University, Nanjing 210023, People’s Republic of China

Jiangsu Engineering Research Center on Information Security and Privacy Protection Technology, Nanjing 210023,

People’s Republic of China

School of Information Systems, Singapore Management University, 80 Stamford Road, Singapore 178902, Singapore

E-mail: bela_suno@163.com

Abstract: Certiﬁcateless public key cryptosystem (CLPKC) improves the identity based public key cryptosystem to be key-

escrow free. Many research works on CLPKC have been presented so far. However, the revocation problem in CLPKC still

lacks effective solutions. The current revocation approaches suffer from either low efﬁciency or security weakness. In this

study, we propose the ﬁrst ‘scalable revocable’ certiﬁcateless encryption (RCLE) scheme against ‘decryption key exposure’.

The scheme is provably secure in the standard model. Moreover, we give a second interesting RCLE scheme whose

decryption key is very short.

1 Introduction

In a public key cryptosystem, suppose Alice wants to send a

conﬁdential message to Bob. She obtains Bob’s public key

certiﬁcate from the Certiﬁcate Authority, and checks the

validity of the certiﬁcate. If the certiﬁcate has not expired

and has not been revoked, Alice retrieves Bob’s public key

to encrypt the message. As is widely known, it is very

costly to perform certiﬁcate management. To overcome this

weakness, in 1984, Shamir proposed the famous

‘Identity-based Cryptography’ [1]. A user’s unique identity

is used as a public key. So there is no need to issue a public

key certiﬁcate to prove the authenticity. The according

private key is fully computed by a third party called Private

Key Generator (PKG). It is noteable that the PKG can

decrypt any ciphertext. In order to solve the inherent key

escrow problem in identity-based cryptosystem, in 2003,

Al-Riyami and Paterson introduced certiﬁcateless public key

cryptosystem (CLPKC) [2]. In this type of cryptosystem, a

user’s private key is just partially generated by a Key

Generation Centre (KGC). The user also selects a secret

value as the other part of the private key.

To a public key cryptosystem, how to achieve revocation

when a user’s private key is compromised or the contract

runs out, is an important and necessary problem. In the

conventional PKI, the revocation techniques are such as

certiﬁcate revocation lists, online certiﬁcate status protocol

[3] and Novomodo [4]. In the certiﬁcate-free public key

system, the revocation is in a different way from that of

PKI. In 2001, Boneh and Franklin [5] suggested that the

PKG computes users’ private keys in every time period.

PKG can revoke a user via stoping the generation of new

private keys for the user. Instantaneous revocation can be

obtained by employing a third party called SEM [6].

Boldyreva et al. [7] presented the ﬁrst scalable ‘revocable

identity based encryption’ (RIBE) scheme, which was

improved by Libert and Vergnaud [8] to reach a strong

security level. In [9], Tsen g and Tsai claimed that

Boldyreva et al.’s scheme requires a secure channel to

do key updating, and presented the ﬁrst revocable id entity

based encryption scheme with a public channel based on

the Boneh–Franklin scheme. However, Jae Hong SEO and

Keita EMURA pointed out the mistake of what Tseng- Tasi

claimed in their paper [9] that Boldyreva

et al.’s scheme

requires secure channels in the key update phase. So the

contribution of the ﬁrst RIBE with a public channel [9]is

invalid. Moreover, the authors pointed out that it is simple

to remove secure channels from the Boneh–Franklin RIBE.

In contrast, there are less results on the revocation problem

of the certiﬁcateless cryptosystem. The mostly mentioned

SEcurity Mediator (SEM) [10–12] seems unpopular in

some application surroundings, since every user cannot do

decryption and signing independently. A natural approach

[10, 13] is to update users’ partial private keys regularly in

every time period. However, the need for secret channels to

transmit all partial private keys is very costly. In 2013,

Shen et al.[14] gave a solution to remove secret channels

for key-updating. However, their scheme suffers from

security weakness.

In PKC2013 [15], Seo et al. proposed the notion of

decryption key exposure (DKE) in the revocable identity

based setting. To resist DKE, a decryption key can be no

longer the simple combination of an initial private key and

an updated time key, but to add a new randomness to

compute the decryption key. However, this technique

inevitably introduces redundancy in a user’s decryption key

www.ietdl.org

158

The Institution of Engineering and Technology 2015

IET Inf. Secur., 2015, Vol. 9, Iss. 3, pp. 158–166

doi: 10.1049/iet-ifs.2014.0145

下载后可阅读完整内容，剩余8页未读，立即下载

weixin_38699784

粉丝: 5
资源: 954

可扩展可撤销无证书加密：抵御解密密钥暴露

加密解密密钥

易飞用户加密解密

cryptjs：一个加密解密,支持密钥的php类库

分层可撤销加密代码

华三交换机链路加密算法

基于属性的分层可撤销加密代码

输入可包含所有可见字符的字符串，并随机生成一个并能随机产生一个置乱表作为密钥保存到文件并显示出来，然后根据置乱表进行数据变换加密。在解密时导入文件中的替换表，根据该置乱表进行解密。

cp-abe可撤销加密算法是基于什么数学难题设计的？

PKI的核心服务有哪些？关键技术是什么？PKI服务的优点有哪些？

什么是PKI（公钥基础设施）

最新资源