A security cloud audit method and system with updatable verification label

[0071] In this embodiment, a security cloud auditing method whose verification label can be updated is applied in a cloud storage environment composed of a user, a third-party audit organization TPA, and a cloud server. The security cloud auditing method is performed in the following steps:

[0072] Step 1. Initialization:

[0073] Step 1.1, such as figure 1 As shown, the user generates two multiplicative cyclic groups G whose order is a prime number q 1 and G 2 , two collision-resistant hash functions H 1 :{0,1} * →G 1 and H 2 :G 2 →G 1 , a computable bilinear pairing Group G 1 The two generators g and u and the user's initial public-private key pair (SK C,0 , PK C,0 ) and the initial public-private key pair (SK T,0 , PK T,0 ),in As the public key of the user and the third-party audit agency TPA respectively, and the initial public-private key pair (SK T,0 , PK T,0 ) to the third-party auditor TPA;

[0074] Step 1.2, the user sets the public parameters as (...