一种可证明安全的匿名可认证密钥协商协议

提出了一种新的双方密钥协商协议,新方案采用紧致结构以确保方案的匿名性。之后利用可证明安全理论对新方案进行了严格的安全性分析,同时对方案的匿名性和AKE安全性进行了论证。新方案的消息长度较短,且只需两轮交互,与类似方案相比有较明显的性能优势。     

Escrowable identity-based authenticated key agreement protocol with strong security

Escrowable identity-based authenticated key agreement protocols are welcome in certain closed groups applications, where audit trail is a legal requirement. In this paper, we present a strongly secure one-round escrowable identity-based two-party authenticated key agreement protocol, which captures all basic desirable security properties including perfect forward secrecy, ephemeral secrets reveal resistance and so on, and is provably secure in the extended Canetti–Krawczyk (eCK) model. We show that the security of the protocol can be reduced to the standard computational bilinear Diffie–Hellman assumption in the random oracle model. Assuming that no adversary can obtain the master private key for the escrow mode, our scheme is secure as long as each party has at least one uncompromised secret. To the best of our knowledge, our scheme is the first escrowable identity-based authenticated key agreement protocol provably secure in the eCK model.     

A novel pairing-free certificateless authenticated key agreement protocol with provable security

Recently, He et al. (Computers and Mathematics with Applications, 2012) proposed an efficient pairing-free certificateless authenticated key agreement (CL-AKA) protocol and claimed their protocol was provably secure in the extended Canetti-Krawczyk (eCK) model. By giving concrete attacks, we indicate that their protocol is not secure in the eCK model. We propose an improved protocol and show our improvement is secure in the eCK model under the gap Diffie-Hellman (GDH) assumption. Furthermore, the proposed protocol is very efficient.     

新的基于椭圆曲线的三方口令认证密钥协商协议

口令认证密钥协商使得参与通信的用户用一个低熵的口令就可以实现实体认证,并能通过不安全的信道安全地生成共享的高熵会话密钥。为此,设计了一种新的基于椭圆曲线的三方口令认证密钥协商协议,新协议将参与者的口令巧妙地隐藏在传输的消息中,确保了口令的安全性。新协议的安全性基于椭圆曲线离散对数问题,服务器并不需要完全可信。安全性分析和性能分析显示,新协议以较低的代价实现了通信双方的安全通信。     

高效的强安全的基于身份认证密钥协商协议

现有的基于身份(ID)认证协议大多在CK模型中被证明是安全的,而CK模型比扩展的CK模型(eCK模型)更弱。基于NAXOS方法,利用双线性对设计了一种新协议,并基于随机预言假设和GBDH假设,在eCK模型中证明了协议的安全性。与其他的基于身份认证协议相比,新协议的计算复杂度和通信复杂度较低;满足主密钥前向安全性和完美前向安全性,并抗密钥泄漏伪装。     

A round-optimal three-party ID-based authenticated key agreement protocol

In this paper, we propose a round-optimal identity-based authenticated key agreement protocol for a three-party setting in which three parties can actually transmit messages simultaneously. We then give its security proof in the random oracle model under the Bilinear Diffie–Hellman assumption.     

An efficient identity-based tripartite authenticated key agreement protocol

The tripartite authenticated key agreement protocol enables three entities to authenticate each other and agree on a session key over an insecure public network. In this paper, we propose an identity-based tripartite authenticated key agreement protocol. Compared with the previous identity-based tripartite authenticated key agreement protocols, the novel protocol requires only one round, lower communication cost and smaller computation cost. We provide security proof of the proposed protocol based on the intractability of the Bilinear Diffie–Hellman problem and intractability of the discrete logarithm problem in the random oracle model.     

Efficient three-party authenticated key agreement protocol in certificateless cryptography

Key agreement protocols are multi-party protocols in which entities exchange public information allowing them to create a common secret key that is known only to those entities and which cannot be predetermined by any party. Key agreement can be achieved using a public key infrastructure or identity-based cryptography. However, the former suffers from a heavy certificate management burden, while the latter is subject to the so-called key escrow problem. Recently, the notion of certificateless public key cryptography (CL-PKC) was introduced to mitigate these limitations. In this paper, we introduce the notion of three-party authenticated key agreement into CL-PKC and propose a concrete certificateless three-party authenticated key agreement protocol. We show that the proposed protocol is secure (i.e. conforms to defined security attributes) while being efficient.     

A pairing-free identity-based authenticated key agreement protocol with minimal message exchanges

Based on the computational Diffie-Hellman problem, this paper proposes an identity-based authenticated key agreement protocol which removes bilinear pairings. Compared with previous protocols, the new protocol minimizes message exchange time with no extra cost. The protocol provides strong security guarantees including key compromise impersonation resilience, perfect forward secrecy, and master key forward secrecy. A security proof with the modular approach in the modified Bellare-Rogaway model is also provided.     

An improved two-party identity-based authenticated key agreement protocol using pairings

Two-party authenticated key agreement protocols using pairings have gained much attention in the cryptographic community. Several protocols of this type where proposed in the past of which many were found to be flawed. This resulted in attacks or the inability to conform to security attributes. In this paper, we propose an efficient identity-based authenticated key agreement protocol employing pairings which employs a variant of a signature scheme and conforms to security attributes. Additionally, existing competitive and the proposed protocol are compared regarding efficiency and security. The criteria for efficiency are defined in this paper, whereas the criteria for security are defined by the fulfilment of security attributes from literature.     

新型三方口令认证密钥协商协议的安全性分析与改进

口令认证密钥协商(PAKA)是认证密钥协商(AKA)中的重要分支之一。研究了一种新型三方口令认证密钥协商--3REKA的安全性,发现如果参与双方的验证值丢失,将导致严重的中间人攻击,这一攻击的结果是敌手可以与参与者各自建立独立的会话密钥。描述了这一攻击,并对原协议进行了改进,提出了I-3REKA协议。安全性和性能分析表明,所提出的协议以较低的计算量实现了参与双方的安全通信。     

一种新的双方认证密钥协商协议的安全性分析

2010年,Mohammad等人提出了一种新的双方认证密钥协商协议(MOHAMMAD Z, CHEN Y, HSU C, et al. Cryptanalysis and enhancement of two-pass authenticated key agreement with key confirmation protocols. IETE Technical Review, 2010,27(3):252-65)。新协议以较高的运算效率实现了参与者双方的身份认证和密钥协商。对该协议的单轮版本进行了安全性分析,通过模拟协议中某些信息丢失后协议双方的通信过程,发现如果协议中的一些秘密信息丢失,敌手可以发起信息泄露伪装攻击、密钥泄露伪装攻击和一般定义下的伪装攻击,也无法抵抗中间人攻击。这些攻击都可以使得敌手冒充合法参与者发起或回应会话。     

Strongly secure identity-based authenticated key agreement protocols

In this paper, we present a strongly secure identity-based (ID-based) two-party authenticated key agreement (AKA) protocol, which captures all basic desirable security properties including master key forward secrecy, ephemeral secrets reveal resistance and so on, and is provably secure in the extended Canetti-Krawczyk (eCK) model. The security of the protocol can be reduced to the standard Computational Bilinear Diffie-Hellman assumption in the random oracle model. Our scheme is secure as long as each party has at least one uncompromised secret. Also, we give a strongly secure variant of the protocol. The variant has a much lower computational overhead than the original scheme, while its security relies on the Gap Bilinear Diffie-Hellman assumption. Currently, there are few ID-based AKA protocols that are provably secure in the strong eCK model. Compared with previous ID-based AKA schemes, our protocols have advantages over them in security or efficiency.     

Perfect forward secure identity-based authenticated key agreement protocol in the escrow mode

The majority of existing escrowable identity-based key agreement protocols only provide partial forward secrecy. Such protocols are, arguably, not suitable for many real-word applications, as the latter tends to require a stronger sense of forward secrecy—perfect forward secrecy. In this paper, we propose an efficient perfect forward-secure identity-based key agreement protocol in the escrow mode. We prove the security of our protocol in the random oracle model, assuming the intractability of the Gap Biline...     

An improved identity-based key agreement protocol and its security proof

We revisit the identity-based (ID-based) key agreement protocol due to Ryu et al. The protocol is highly efficient and suitable for real-world applications despite offering no resilience against key-compromise impersonation (K-CI). We show that the protocol is also insecure against reflection attacks. We propose a slight modification to the protocol and prove its security in a widely accepted model.     

Certificateless and identity-based authenticated asymmetric group key agreement

Group key agreement (GKA) is one of the traditional ways to guarantee the subsequent secure group communications. However, conventional GKA protocols face two limitations, i.e., they require two or more rounds to establish secure channels and are sender restricted. Asymmetric group key agreement (AGKA) eliminates above two limitations of GKA. It allows a group of users to establish a public group encryption key and a different secret decryption key of each group member in one round. Any user who knows the group encryption key can encrypt to the group members. This paper studies authenticated AGKA in certificateless and identity-based public key cryptosystems. We formalize the security model of certificateless authenticated asymmetric group key agreement and realize a one-round certificateless authenticated asymmetric group key agreement protocol to resist active attacks in the real world. We also investigate the relation between certificateless authenticated AGKA and identity-based authenticated AGKA. We propose a concrete conversion from certificateless authenticated AGKA to session key escrow-free identity-based authenticated AGKA.     

Two improved two-party identity-based authenticated key agreement protocols

Many authenticated key agreement protocols based on identity information were published in recent years. Hsieh et al. presented their protocol in 2002. However, Tseng et al. found a flaw in the protocol which resulted in a key compromise impersonation attack. Later, Tseng proposed his protocol conforming which conforms to all desirable security properties and is efficient. In this paper we propose two new two-party identity-based authenticated key agreement protocols. The first is based on Hsieh et al.'s protocol and makes it immune against Tseng et al.'s attack, while the second is an efficiently improved protocol based on Tseng's protocol.     

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.     

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.