Research On Password-based Remote User Authentication Schemes Using Smart-cards

With the rapid development of e-commerce, e-health as well as e-government, user authentication has become an essential mechanism to assure the distributed systems’security and privacy from malicious adversaries. Owing to its high level of security, portability, simplicity and cryptographic properties, smart card based password authentication has been widely adopted in various applications. After twenty years of intensive research, the security requirements and desirable properties that such schemes can support gradually tend to be ideal. A common feature among most of the previous schemes is that, the smart card is assumed to be tamper-resistant, i.e., the sensitive parameters stored in the smart card cannot be extracted. However, recent research results have shown that the secret information stored in the smart card could be extracted by some means, such as monitoring the power consumption, reverse engineering or analyzing the leaked information, which invalidates the basic assumption that the traditional schemes are based on. Consequently, the design of a secure and efficient scheme based on the non-tamper resistance assumption of the smart cards has been a hot topic in the domain of lightweight cryptographic protocols since2006.Unfortunately, under this new assumption, how to design a secure and efficient smart card based password authentication scheme is really a big challenge. On the one hand, there are various security requirements and desirable features that a practical scheme should satisfy; on the other hand, the smart card itself is resource-constrained and computationally intensive operations are not suitable for such environments. Although there are a number of schemes using non-tamper resistant smart cards proposed in recent years, all of them have been found severely flawed shortly after they were first put forward. The main reason of such dilemma is that, previous researchers either only focus on the realization of some security requirements or admired properties, or just present an enhancement after cryptanalysis of a problematic scheme, no systematic work or rationale is given. To alleviate this situation, in this thesis, taking the password authentication schemes using non-tamper resistant smart cards as the main line, we focus on the evaluation criteria, the analysis and design principles, as well as the design of new schemes. And our contributions are as follows:1) Three recently proposed smart-card-based password authentication schemes are investigated. Firstly, we cryptanalyze the RSA-based scheme proposed by Xie et al. in2010, and find it vulnerable to replay attack and key compromise impersonation attack. Secondly, the password-based authentication key exchange protocol presented by Hao et al. in2011is analyzed, and we find it susceptible to offline password guessing attack and key compromise impersonation attack. In addition, it is subject to the clock synchronization problem. Thirdly, Hsieh et al.’s scheme is scrutinized. This scheme only employs lightweight cryptographic primitives such as Hash function and XOR operations, and thus it is very efficient. Unfortunately, we point out that it cannot withstand offline password guessing attack and insider attack. Moreover, it is not repairable and not well-suited to mobile environments.2) The relationships among the evaluation criteria are examined. To the best of our knowledge, we are the first to put forward three general principles for smart card based password authentication:(i) public-key techniques are indispensable to resist against offline password guessing attack and to preserve user anonymity under the non-tamper resistance assumption of the smart cards;(ii) at least two exponentiation (respectively elliptic curve point multiplication) operations conducted on the server side are necessary for achieving forward secrecy; and (iii) there is an unavoidable trade-off when fulfilling the goals of local password update and resistance to smart card loss attack.3) A novel RSA-based password authentication scheme using smart cards for resource-constrained environments is proposed. Before giving our new scheme, we investigate the scheme proposed by Fang et al. in2011. For the sake of efficiency, Fang et al.’s scheme only involves symmetric cryptographic primitives (such as Hash function), which violates the "public key principle" and it is inherently unable to resist against offline password guessing attack. Accordingly, based on the observation that the computation cost of RSA encryption and the corresponding decryption is quite asymmetric, we advance a secure and efficient scheme and its security is analyzed by heuristics. In comparison with related schemes, our scheme is superior in the efficiency at the client side and thus is more suitable for mobile environments.4) An "ideal scheme" proved secure in the random oracle model is proposed. Based on the intractability of CDH problem, we put forward a provably secure scheme that can satisfy all the security requirements and provide all the desirable properties, which highly indicates the settlement of an open problem raised by Madhusudhan and Mittal in Journal of Network and Computer Applications in early2012. Besides, in this scheme, we propose the concept of "fuzzy verifier" which well resolves the problem that no previous scheme can achieve the goals of local password update and resistance to smart card loss attack at the same time.