基于椭圆曲线的跨域端到端口令认证密钥协商协议

跨域端到端口令认证密钥协商协议(C2C-PAKA)的主要目的是使分布在不同域中持有不同口令的两个客户端可以在各自服务器的协助下实现相互认证并协商出共同的会话密钥。本文中,我们基于椭圆曲线上的离散对数问题,在直接通信架构下给出一个跨域的口令认证的密钥协商协议。该协议中,诚实的服务器是不能获取任何关于会话密钥的值。各参与方之间能够实现相互认证。与同类协议比较,该协议具有较小的通信负担和计算负担,更易于实现。此外,协议还能够抵抗字典攻击、口令泄露模仿攻击和未知会话密钥共享攻击等通用攻击类型,同时能够实现前向安全、无密钥控制和已知会话密钥安全等安全属性。     

基于自验证公钥的跨域口令认证密钥协商协议

结合自验证公钥密码学和口令构造了一个用户可以直接通信的跨域口令认证密钥协商协议。域服务器通过口令认证实现对域内用户的认证, 并与对方域服务器一起协助用户完成认证和密钥协商。该过程中, 域服务器不能获取关于会话密钥的任何信息, 且各参与方之间能够实现相互认证。与同类协议相比, 该协议需要较小的计算和通信代价, 并能抵抗字典攻击和未知会话密钥共享攻击。     

一种使用扩展混沌映射的基于生物特征密钥协商协议

认证密钥协商协议是两个或多个用户产生一个共享的安全会话密钥.在开放的网络中,用户可以使用共享的会话密钥加密/解密消息达到安全通信.近来,基于生物特征和口令的远程认证方案得到研究者的广泛关注.受到切比雪夫映射的半群特性和基于混沌映射的密钥协商协议启发,本文提出一种使用扩展混沌映射的基于生物特征密钥协商协议.新协议没有采用模指数运算或者椭圆曲线的点乘运算.安全性分析表明,新协议具有显著特征并且能抵抗各类攻击,包括特权用户攻击,重放攻击,口令猜测攻击等.性能分析表明,与其它相关协议比较,新协议的计算复杂度较低.     

改进的三方口令认证密钥交换协议

基于三方的口令认证密钥交换（3PAKE）协议是客户通过与可信服务器共享一个口令验证元,在两客户进行通信时通过此可信服务器进行会话密钥的建立与共享,从而进行通信。首先对李文敏等人提出的协议进行安全性分析,发现该协议易受离线字典攻击和服务器泄露攻击。提出了一个改进协议,该协议能够提供双向认证、会话密钥机密性和前向安全性,能够有效抵抗多种攻击,包括离线字典攻击和服务器泄露攻击。     

具有强匿名性的网关口令认证密钥交换协议

网关口令认证密钥交换协议允许用户和网关在服务器的协助下建立起一个共享的会话密钥,其中用户和服务器之间的认证通过低熵的口令来完成.已有的网关口令认证密钥交换协议对用户的匿名性研究不足.该文基于Diffie-Hellman密钥交换提出了具有强匿名性的网关口令认证密钥交换协议,并且在随机预言模型下基于标准的DDH假设证明了协议的安全性.新协议可以抵抗不可检测在线字典攻击并且计算效率高,安全性和计算效率都优于已有的同类协议.     

简单的三方口令密钥交换协议

基于口令认证的三方密钥交换协议（3PAKE）是通信双方在认证服务器的帮助下能在公开非安全的信道上协商并建立一个共享会话密钥。虽然目前有不少该方面的研究,但多数后来被证实易受攻击。本文给合以往的研究,提出一个不需服务器公钥体系的简单的基于口令认证的三方密钥交换协议。本文的协议不仅能抵抗各种攻击,而且计算成本和通信成本都比较低。     

改进的基于口令的群密钥协商协议

群密钥协商协议是保证后续群组安全通信的重要手段之一。为此,研究Byun和Lee提出的基于口令的群密钥协商协议,指出该协议不能抵抗不可检测的在线字典攻击。基于这个发现,对该方案进行改进,提出一种新的群密钥协商协议。安全性分析表明,该协议可以抵抗基于口令的群密钥协商协议的常见攻击。     

基于混沌映射的用户匿名三方口令认证密钥协商协议

在基于混沌的三方口令认证密钥协商协议中,用户通过低熵的口令实现相互认证和共享会话密钥,以避免在身份认证过程中公钥基础设施或存储用户长期密钥的安全威胁。通过分析Lee提出的基于混沌映射的口令认证密钥协商协议,发现其协议不能进行口令变更,而且仅适用于用户和服务器之间的两方通信。为了改进此方案,提出两个基于切比雪夫混沌映射的用户匿名三方口令认证密钥协商协议,包括基于时钟同步的密钥协商方案和基于随机数的密钥协商方案。其中基于时钟同步的用户匿名三方口令认证密钥协商协议通信量少,基于随机数的用户匿名三方口令认证密钥协商协议更容易实现。两个方案的优点是用户仅选择一个简单的口令进行相互认证和密钥协商,服务器不需要再保护用户口令表,避免了口令相关的攻击,而且在相互认证过程中用户使用临时身份和哈希函数,实现用户匿名性,在增强协议安全性的同时,减少了通信过程中消息的数量,提高了协议的执行效率,具有完美前向安全,并用BAN逻辑证明了其安全性。     

基于PKI体系的跨域密钥协商协议

基于口令的跨域密钥协商协议和Kerberos协议无法抵抗口令猜测攻击,在金融、航天等通信安全需求高的场所,需要一种更有效的协议来保证通信安全。给出一种新的基于PKI体系的跨域密钥协商协议,采用公钥算法保证数据传输的安全,结合使用Diffie-Hellman协议生成会话密钥。协议有效地解决了利用预置共享密钥参与加/解密实施中间人攻击,以及Kerberos弱口令导致的攻击者可以实施口令猜测攻击的问题。跨域通信的公钥信息仅存储在各自域认证服务器,域内用户不需要配置跨域服务器的公钥信息,降低了配置复杂度、域内用户和域认证服务器之间密钥管理的复杂性,同时提高了域服务器鉴别身份的能力和信息机密性,使其免疫多种攻击,具有良好的前向安全性和扩展性。     

基于椭圆曲线的加密密钥交换协议

加密密钥交换协议(EKE)的目的是利用安全性低的口令协商安全性高的密钥,进而利用密钥对以后的通信进行加密或身份认证,从而实现安全通信.基于验证元的EKE是针对服务器泄露攻击问题提出的.本文基于椭圆曲线密码系统的特点,给出了一个基于验证元的3EKE,该协议中,服务器通过口令实现对用户的认证;协议能够抵抗服务器泄露等攻击,...     

Shoulder-surfing-proof graphical password authentication scheme

The graphical password authentication scheme uses icons instead of text-based passwords to authenticate users. Icons might be somehow more familiar to human beings than text-based passwords, since it is hard to remember the latter with sufficient security strength. No matter what kind of password is used, there are always shoulder-surfing problems. An attacker can easily get text-based password or graphical password by observation, capturing a video or recording the login process. In this paper, we propose a shoulder-surfing-proof graphical password authentication scheme using the convex-hull graphical algorithm. We give evaluation and comparisons to demonstrate the security strength and the functionality advantages of our scheme.     

An Enhanced Graphical Authentication Scheme Using Multiple-Image Steganography

Most remote systems require user authentication to access resources. Text-based passwords are still widely used as a standard method of user authentication. Although conventional text-based passwords are rather hard to remember, users often write their passwords down in order to compromise security. One of the most complex challenges users may face is posting sensitive data on external data centers that are accessible to others and do not be controlled directly by users. Graphical user authentication methods have recently been proposed to verify the user identity. However, the fundamental limitation of a graphical password is that it must have a colorful and rich image to provide an adequate password space to maintain security, and when the user clicks and inputs a password between two possible grids, the fault tolerance is adjusted to avoid this situation. This paper proposes an enhanced graphical authentication scheme, which comprises benefits over both recognition and recall-based graphical techniques besides image steganography. The combination of graphical authentication and steganography technologies reduces the amount of sensitive data shared between users and service providers and improves the security of user accounts. To evaluate the effectiveness of the proposed scheme, peak signal-to-noise ratio and mean squared error parameters have been used.     

A Human-Cognitive Perspective of Users’ Password Choices in Recognition-Based Graphical Authentication

ABSTRACT

Graphical password composition is an important part of graphical user authentication which affects the strength of the chosen password. Considering that graphical authentication is associated with visual search, perception, and information retrieval, in this paper we report on an eye-tracking study (N = 109) that aimed to investigate the effects of users’ cognitive styles toward the strength of the created passwords and shed light into whether and how the visual strategy of the users during graphical password composition is associated with the passwords’ strength. For doing so, we adopted Witkin’s Field Dependence-Independence theory, which underpins individual differences in visual information and cognitive processing, as graphical password composition tasks are associated with visual search. The analysis revealed that users with different cognitive processing characteristics followed different patterns of visual behavior during password composition which affected the strength of the created passwords. The findings underpin the need of considering human-cognitive characteristics as a design factor in graphical password schemes. The paper concludes by discussing implications for improving recognition-based graphical passwords through adaptation and personalization techniques based on individual cognitive characteristics.     

基于(r,n)门限的密钥恢复方案

随着计算机技术的普及发展,信息安全越来越受到重视,许多系统借助加密技术来保证信息在存储传输过程中的安全性,而密码系统中所使用的密钥或口令的安全性则成为系统的薄弱环节,密钥的丢失会给用户造成不必要的损失。文中介绍了一种应用(r,n)门限进行密钥恢复的新方案,该方案综合应用门限技术和因特网中广泛使用的回答问题认证模式来恢复丢失的密钥或口令。与传统密钥的恢复方案相比,具有较好的易用性和安全性。     

Token-based graphical password authentication

Given that phishing is an ever-increasing problem, a better authentication system is required. We propose a system that uses a graphical password deployed from a Trojan and virus-resistant embedded device. The graphical password utilizes a personal image to construct an image hash, which is provided as input into a cryptosystem that returns a password. The graphical password requires the user to select a small number of points on the image. The embedded device will then stretch these points into a long alphanumeric password. With one graphical password, the user can generate many passwords from their unique embedded device. The image hash algorithm employed by the device is demonstrated to produce random and unique 256-bit message digests and was found to be responsive to subtle changes in the underlying image. Furthermore, the device was found to generate passwords with entropy significantly larger than that of users passwords currently employed today.     

基于RLWE的生物特征认证密钥交换协议

在后量子密码学中,针对密钥交换协议存在口令容易丢失以及难以实现相互认证的安全缺陷,提出了一个新的基于环上误差学习的生物特征认证密钥交换协议。该协议根据环上误差学习问题构造的密码体制具有密钥及密文尺寸短、运行效率高等优势,并采用生物特征和口令作为长期密钥,同时通过Peikert式错误协调机制从各自的环元素中协调出随机均匀的会话密钥,实现了服务器对客户的显式认证。性能分析结果表明,该方案可抵抗用户假冒攻击,安全属性更高,提高了通信效率。     

一种增强的智能卡口令认证方案

Hwang等人提出了基于ElGamal算法的智能卡口令认证方案,其安全性依赖于计算有限域上离散对数的难度。Chan等人分析了该方案的安全缺陷,并进行了改进。最近,Awasthi等人指出了改进方案中的安全缺陷,并提出了一种新方案,但新方案仍然存在缺陷。针对新方案的缺陷,基于“一次一密”和“动态口令”,提出了一种增强的智能卡口令认证方案。该方案允许用户自由选择口令,能够抵御重放攻击、内部攻击,能双向认证,具备强安全修复性。     

一种基于智能卡的口令认证方案

给出了一个基于智能卡的远程访问口令认证方案，它能够对登录口令进行检验而不需要检索口令表。它利用了公钥密码系统的签名特性，其安全性依赖于离散对数问题和因数分解问题。特点是网络用户可以自由选择其口令，通过对口令增加时间戳还可抵抗重放攻击。     

An Enhanced Drawing Reproduction Graphical Password Strategy

Passwords are used in the vast majority of computer and communication systems for authentication. The greater security and memorability of graphical passwords make them a possible alternative to traditional textual passwords. In this paper we propose a new graphical password scheme called YAGP, which is an extension of the Draw-A-Secret (DAS) scheme. The main difference between YAGP and DAS is soft matching. The concepts of the stroke-box, image-box, trend quadrant, and similarity are used to describe the images characteristics for soft matching. The reduction in strict user input rules in soft matching improves the usability and therefore creates a great advantage. The denser grid granularity enables users to design a longer password, enlarging the practical password space and enhancing security. Meanwhile, YAGP adopts a triple-register process to create multi-templates, increasing the accuracy and memorability of characteristics extraction. Experiments illustrate the effectiveness of YAGP.     

Graphical One-Time Password (GOTPass): A usability evaluation

ABSTRACT

Complying with a security policy often requires users to create long and complex passwords to protect their accounts. However, remembering such passwords is difficult for many and may lead to insecure practices, such as choosing weak passwords or writing them down. In addition, they are vulnerable to various types of attacks, such as shoulder surfing, replay, and keylogger attacks (Gupta, Sahni, Sabbu, Varma, & Gangashetty, 2012) One-Time Passwords (OTPs) aim to overcome such problems (Gupta et al., 2012); however, most implemented OTP techniques require special hardware, which not only adds cost, but there are also issues regarding its availability (Brostoff, Inglesant, & Sasse, 2010). In contrast, the use of graphical passwords is an alternative authentication mechanism designed to aid memorability and ease of use, often forming part of a multifactor authentication process. This article is complementary to the earlier work that introduced and evaluated the security of the new hybrid user-authentication approach: Graphical One-Time Password (GOTPass) (Alsaiari et al., 2015). The scheme aims to combine the usability of recognition-based and draw-based graphical passwords with the security of OTP. The article presents the results of an empirical user study that investigates the usability features of the proposed approach, as well as pretest and posttest questionnaires. The experiment was conducted during three separate sessions, which took place over five weeks, to measure the efficiency, effectiveness, memorability, and user satisfaction of the new scheme. The results showed that users were able to easily create and enter their credentials as well as remember them over time. Participants carried out a total of 1,302 login attempts with a 93% success rate and an average login time of 24.5 s.