Efficient and Forward-Secure Attribute-Based Sanitizable Signature Scheme

In the attribute-based signature (ABS) scheme, the secret key of the signer is generated by attribute authority with different attributes, and the signature can be generated successfully only when the attributes meet the given signing policy. The verifier does not need to know the identity of the signer to determine whether the signature is valid. As a result, ABS has attracted wide attention due to its anonymity and fine-grained access control. In ABS scheme, once the key leakage occurs, the attacker can use the leaked key to generate a valid signature. The original message often contains some sensitive information. For example, in e-health or electronic finance scenario, personal privacy information is contained in personal medical records or transaction records. If the original message is not desensitized, sensitive personal information will be leaked. In order to solve the problems of key leakage and sensitive information leakage, an efficient and forward-secure attribute-based sanitizable signature (FABSS) scheme is proposed. The security of FABSS is reduced to the \eta -DHE ( \eta -Diffie-Hellman exponent) assumption problem under the standard model. The proposed scheme not only protects signer privacy and supports fine-grained access control, but also has the ability to hide sensitive information and resist key leakage. In addition, the length of signature is constant, and only a constant number of pairing operations need to be calculated in the verification stage. Experimental analysis shows that the performance of the proposed scheme is efficient.