An Improved Data Backup Scheme Based on Multi-Factor Authentication
Jinghai Yi, Yunhua Wen · 2023
Remote backup is an effective alternative to local backup. It overcomes the shortcomings of local backup that is easy to be stolen and tampered with. In order to protect sensitive information, it is usually necessary to encrypt the sensitive information before uploading to the remote server. How to protect the encryption key used in the remote backup scheme is a crucial issue. Liu et al. (IET Information Security 2017) designed a data backup scheme using secret sharing scheme and mutual authentication scheme. They divided the key into three parts and stored them in the laptop, smart card and server respectively. The key can be reconstructed from any two parts. However, Hu et al. (IET Information Security 2019) found that Liu et al.’s scheme cannot resist offline password guessing attack, server impersonation attack and user impersonation attack. Then they proposed an enhanced scheme. Unfortunately, we find that Hu et al.’s scheme cannot cope with offline guessing attack, replay attack, denial of service attack. Besides, their scheme does not consider the case that the smart card and the laptop may be tampered with. Moreover, in their scheme, a malicious server may transmit false information to the laptop or smart card which may lead the user to reconstruct an incorrect key. To solve the above problems, we propose an improved data backup scheme based on multifactor authentication. We show that our scheme can resist the above adversary attacks. Besides, our scheme can detect tampering of smart cards and laptops. Moreover, our scheme can quickly detect the incorrect information transmitted by a malicious server.