适用于双方频繁通信的密钥交换协议

首先对以前提出的一个高效的基于验证元的三方密钥交换协议进行了安全性分析,指出了它容易受到服务器密钥泄露攻击等安全威胁,且缺乏前向安全性;并以此为基础,针对大多数现存的基于验证元的3PAKE协议均难以抵御服务器密钥泄露攻击的现状,提出了一个新的3PAKE协议。通过安全性分析,证明了新协议比原协议更安全,能够抵御各种已知的攻击,且与现有的大多数同类协议相比具有更高的效率。     

Provably secure three-party password authenticated key exchange protocol in the standard model

Three-party password authenticated key exchange protocol is a very practical mechanism to establish secure session key through authenticating each other with the help of a trusted server. Most three-party password authenticated key exchange protocols only guarantee security in the random oracle model. However, a random oracle based cryptographic construction may be insecure when the oracle is replaced by real function. Moreover, some previous unknown attacks appear with the advance of the adversary capability. Therefore, a suitable standard model which can imitate a wider variety of attack scenarios for 3PAKE protocol is needed. Aim at resisting dictionary attack, unknown key-share attack and password-compromise impersonation attack, an expanded standard model for 3PAKE protocol is given. Meanwhile, through applying ElGamal encryption scheme and pseudorandom function, a specific three-party password authenticated key exchange protocol is proposed. The security of the proposed protocol is proven in the new standard model. The result shows that the present protocol has stronger security by comparing with other existing protocols, which covers the following security properties: (1) semantic security, (2) key privacy, (3) client-to-server authentication, (4) mutual authentication, (5) resistance to various known attacks, and (6) forward security.     

Provably secure three-party password-based authenticated key exchange protocol

A three-party password-based authenticated key exchange (3PAKE) protocol is a useful mechanism to establish a secure session key in a network. However, most current 3PAKE protocols only achieve “heuristic” security; the underlying hardness assumptions of these protocols are not perfect. We propose a 3PAKE protocol which is provably secure if the Diffie–Hellman problem is computationally infeasible (the CDH assumption), even in the 3eCK model where the adversary is allowed to make more queries and have more freedom than previous models. In our formal proof, we use the trapdoor test technique introduced by Cash, Kiltz and Shoup to construct an efficient decision oracle. As far as we know, our protocol is the first provably secure 3PAKE protocol based on the CDH assumption and the first 3PAKE protocol using the trapdoor test technique for the security proof.     

An efficient three-party authenticated key exchange protocol using elliptic curve cryptography for mobile-commerce environments

For secure communications in public network environments, various three-party authenticated key exchange (3PAKE) protocols are proposed to provide the transaction confidentiality and efficiency. In 2008, Chen et al. proposed a round-efficient 3PAKE protocol to provide the computation and communication efficiency for user authentication and session key exchange. However, we discover that the computation costs and communication loads of their protocol are still high so that it cannot be applied to mobile communications. Therefore, we propose an efficient three-party authenticated key exchange protocol based upon elliptic curve cryptography for mobile-commerce environments. Because the elliptic curve cryptography is used, the proposed 3PAKE protocol has low computation costs and light communication loads. Compared with Chen et al.’s protocol, the proposed protocol is more suitable and practical for mobile-commerce environments.     

标准模型下高效的三方口令认证密钥交换协议

三方口令认证密钥交换协议允许两个分别与服务器共享不同口令的用户在服务器的协助下建立共享的会话密钥,从而实现了用户间端到端的安全通信.现阶段,多数的三方口令认证密钥交换协议都是在随机预言模型下可证明安全的.但在实际应用中,利用哈希函数对随机预言函数进行实例化的时候会给随机预言模型下可证明安全的协议带来安全隐患,甚至将导致协议不安全.以基于ElGamal加密的平滑投射哈希函数为工具,在共同参考串模型下设计了一种高效的三方口令认证密钥交换协议,并且在标准模型下基于DDH假设证明了协议的安全性.与已有的同类协议相比,该协议在同等的安全假设下具有更高的计算效率和通信效率,因此更适用于大规模的端到端通信环境.     

Scalable protocol for cross-domain group password-based authenticated key exchange

Cross-domain password-based authenticated key exchange (PAKE) protocols have been studied for many years. However, these protocols are mainly focusing on multi-participant within a single domain in an open network environment. This paper proposes a novel approach for designing a cross-domain group PAKE protocol, that primarily handles with the setting of multi-participant in the multi-domain. Moreover, our protocol is proved secure against active adversary in the Real-or-Random (ROR) model. In our protocol, no interaction occurs between any two domain authentication servers. They are regarded as ephemeral certificate authorities (CAs) to certify key materials that participants might subsequently use to exchange and agree on group session key. We further justify the computational complexity and measure the average computation time of our protocol. To the best of our knowledge, this is the first work to analyze and discuss a provably secure multi-participant cross-domain group PAKE protocol.     

A secure anonymous routing protocol with authenticated key exchange for ad hoc networks

Anonymity and authenticated key exchange should be paid much more attention in secure mobile ad hoc routing protocols, especially in privacy-vital environment. However, as far as we know, few papers on secure routing protocols have addressed both the anonymity and authenticated key exchange. Therefore, in this paper, we present a new secure anonymous routing protocol with authenticated key exchange for ad hoc networks. In comparison with other previous secure routing protocols, our proposed protocol not only provides the anonymity to the route from the source to the destination, but also integrates the authenticated key exchange into the routing algorithm.     

An efficient client–client password-based authentication scheme with provable security

Recently, Tso proposed a three-party password-based authenticated key exchange (3PAKE) protocol. This protocol allows two clients to authenticate each other and establish a secure session key through a server over an insecure channel. The main security goals of such protocols are authentication and privacy. However, we show that Tso’s protocol achieves neither authentication goal nor privacy goal. In this paper, we indicate that the privacy and authentication goals of Tso’s protocol will be broken by off-line password guessing attack and impersonation attack, respectively. To overcome the weaknesses, we propose an improved 3PAKE protocol to achieve more security and performance than related protocols. The security of the proposed improved protocol is proved in random oracle model.     

A provably secure and efficient two‐party password‐based explicit authenticated key exchange protocol resistance to password guessing attacks

Password‐based two‐party authenticated key exchange (2PAKE) protocol enables two or more entities, who only share a low‐entropy password between them, to authenticate each other and establish a high‐entropy secret session key. Recently, Zheng et al. proposed a password‐based 2PAKE protocol based on bilinear pairings and claimed that their protocol is secure against the known security attacks. However, in this paper, we indicate that the protocol of Zheng et al. is insecure against the off‐line password guessing attack, which is a serious threat to such protocols. Consequently, we show that an attacker who obtained the users' password by applying the off‐line password guessing attack can easily obtain the secret session key. In addition, the protocol of Zheng et al. does not provide the forward secrecy of the session key. As a remedy, we also improve the protocol of Zheng et al. and prove the security of our enhanced protocol in the random oracle model. The simulation result shows that the execution time of our 2PAKE protocol is less compared with other existing protocols. Copyright © 2015 John Wiley & Sons, Ltd.     

A communication-efficient three-party password authenticated key exchange protocol

Three-party password authenticated key exchange (3PAKE) protocols allow two users (clients) to establish a session key through an authentication server over an insecure channel. Clients only share an easy-to-remember password with the trusted server. In the related literature, most schemes employ the server public keys to ensure the identities of both the servers and symmetric cryptosystems to encrypt the messages. This paper describes an efficient 3PAKE based on LHL-3PAKE proposed by Lee et al. Our 3PAKE requires neither the server public keys nor symmetric cryptosystems such as DES. The formal proof of security of our 3PAKE is based on the computational Diffie-Hellman assumption in the random oracle model along with a parallel version of the proposed 3PAKE. The comparisons have shown that our 3PAKE is more practical than other 3PAKEs.     

Efficient verifier-based password-authenticated key exchange in the three-party setting

In the last few years, researchers have extensively studied the password-authenticated key exchange (PAKE) in the three-party setting. The fundamental security goal of PAKE is security against dictionary attacks. The protocols for verifier-based PAKE are additionally required to be secure against server compromise. Some verifier-based PAKE schemes in the three-party setting have been suggested to solve the server compromise problem. Unfortunately, the protocols are vulnerable to an off-line dictionary attack. In this paper, we present an efficient verifier-based PAKE protocol for three-parties that is secure against known-key attacks and provides forward secrecy. To the best of our knowledge, the proposed protocol is the first secure three-party verifier-based PAKE protocol in the literature.     

Simple password-based three-party authenticated key exchange without server public keys

Password-based three-party authenticated key exchange protocols are extremely important to secure communications and are now extensively adopted in network communications. These protocols allow users to communicate securely over public networks simply by using easy-to-remember passwords. In considering authentication between a server and user, this study categorizes password-based three-party authenticated key exchange protocols into explicit server authentication and implicit server authentication. The former must achieve mutual authentication between a server and users while executing the protocol, while the latter only achieves authentication among users. This study presents two novel, simple and efficient three-party authenticated key exchange protocols. One protocol provides explicit server authentication, and the other provides implicit server authentication. The proposed protocols do not require server public keys. Additionally, both protocols have proven secure in the random oracle model. Compared with existing protocols, the proposed protocols are more efficient and provide greater security.     

改进的三方口令验证元认证密钥交换协议

在三方口令认证密钥交换（三方PAKE）协议中,每个用户仅仅需要和服务器共享一个口令,就可以在服务器的协助下与他人进行安全的密钥交换.由于有效地减少了用户管理口令的负担,三方PAKE协议在大规模用户集的安全通信中受到了较多关注.然而,已有的三方PAKE协议大多关注的是服务器利用明文存储用户口令的情形,没有考虑服务器口令文件泄露所造成的巨大威胁.在服务器端存放的是相应于用户口令的验证元的情形下,研究三方PAKE协议的分析和设计.首先分析了一个最近提出的基于验证元的三方PAKE协议,指出该协议易于遭受离线字典攻击,因此未能达到所宣称的安全性;其次,在分析已有协议设计缺陷的基础上,提出了一个新的基于验证元的三方PAKE协议,并在标准模型下证明了所设计的协议的安全性,与已有协议的比较表明,新提出的协议在提供了更高安全性的同时具有可接受的计算和通信效率.     

Design of a password-based authenticated key exchange protocol for SIP

The Session Initiation Protocol (SIP) is a signaling communications protocol, which has been chosen for controlling multimedia communication in 3G mobile networks. In recent years, password-based authenticated key exchange protocols are designed to provide strong authentication for SIP. In this paper, we address this problem in two-party setting where the user and server try to authenticate each other, and establish a session key using a shared password. We aim to propose a secure and anonymous authenticated key exchange protocol, which can achieve security and privacy goal without increasing computation and communication overhead. Through the analysis, we show that the proposed protocol is secure, and has computational and computational overheads comparable to related authentication protocols for SIP using elliptic curve cryptography. The proposed protocol is also provably secure in the random oracle model.     

Authenticated multiple key exchange protocols based on elliptic curves and bilinear pairings

Menezes et al. developed an MQV key exchange protocol that does not use a one-way hash function in 1995. Harn-Lin and Hwang-Shiau-Lai later respectively proposed efficient authenticated key exchange protocols. Lee and Wu recently proposed an enhanced authentication key exchange protocol to solve the drawbacks of the Hwang-Shiau-Lai protocol. Based on the Lee-Wu protocol, this work presents two new authenticated multiple key exchange protocols based on ECC and bilinear pairing. The proposed ECC-based protocol is more efficient than the Harn-Lin, Hwang-Shiau-Lai, and Lee-Wu protocols. Moreover, the proposed pairing-based protocol is better than other protocols in terms of the number of available shared session keys because all agreed session keys can be adopted by the communicating parties in the protocol.     

One-round identity-based key exchange with Perfect Forward Security

Identity-based authenticated key exchange (IBAKE) protocol is one of the most important cryptographic primitives that enables two parties using their identities to establish their common secret keys without sending and verifying public key certificates. Recently, many works have been dedicated to design efficient and secure IBAKE protocols without bilinear pairings which need the heavy computational cost. Unfortunately, most of the proposed protocols cannot provide Perfect Forward Security (PFS) which is a major security goal of authenticated key exchange protocols. In this paper we present an efficient and provably secure IBAKE protocol with PFS. Our protocol relies on the technique known as the concatenated Schnorr signature and it could be viewed as a variant of the protocol proposed by Fiore et al. in 2010. By using the Canetti–Krawczyk security model, we prove that the protocol is secure with PFS under the Computational Diffie–Hellman assumption in the random oracle model. The protocol is of interest since it offers a remarkable combination of advanced security properties and efficiency and its security proof is succinct and intelligible.     

Enhancement of two-factor authenticated key exchange protocols in public wireless LANs

In 2008, Juang and Wu proposed two authenticated key exchange protocols by improving Park and Park’s two-factor authenticated key exchange protocol in public wireless LANs. They pointed out that Park’s protocol was vulnerable to the dictionary attack on the identity protection. The improved protocols requires fewer exchanged messages and provided more secure protection for the client’s identity. In this paper, we propose two protocols require less exchanged messages than Juang’s protocols. In addition to this advantage, we point out that the identity protection of Juang’s protocol is computationally inefficient for the server and efficient identity protection is proposed in the second proposed protocol.     

高效的基于身份的认证密钥协商协议

王圣宝等(王圣宝,曹珍富,董晓蕾.标准模型下可证安全的身份基认证密钥协商协议.计算机学报,2007,30(10):1842-1854)提出的标准模型下可证明安全的基于身份的认证密钥协商协议不具有私钥产生中心(PKG)前向安全性。针对该安全缺陷,提出了一种新的基于身份的认证密钥协商协议,协议中给出了一种利用用户私钥和临时秘密信息联合计算共享秘密的方法,并在标准模型下证明了协议的安全性。与已有协议相比,新协议具有较高的执行效率。同时提出了一种PKG与用户共同协商私钥的方法,即用户的私钥由用户产生的部分秘密信息以及PKG的系统主密钥共同生成,从而有效解决了基于身份的认证密钥协商协议的PKG前向安全性问题。     

强安全的基于身份认证密钥协商协议

LaM acchia等提出了扩展的Canetti-K raw czyk(eCK)安全模型,该模型涵盖了认证密钥协商协议的所有安全特性.鉴于目前大多数基于身份的认证密钥协商协议在eCK模型中是不安全的,利用椭圆曲线加法群构造了一个eCK模型中安全的基于身份认证密钥协商协议.和其它的协议相比,新协议的计算复杂度和通信复杂度较低.新协议提供强安全性,它的安全性证明依赖于随机预言假设和GBDH假设.