Promptly revoke an implementation based on user attribute ciphertext encryption policy attributes

The present invention discloses a method for implementing user attribute timely withdrawal ciphertext encryption attributes based on the policy, which is implemented steps of: establishing the system, the system generates a public key and a master key; encryptor configured to access policies; encryptor encrypts the generated cipher text; attribute authority Center generates user private key and a private key authorization; cloud server configured binary tree path key; cloud server proxy re-encryption, the ciphertext generating a retransmission, to implement an undo user attributes; decryptor to decrypt plaintext obtained. The present invention reduces the burden on the central authority of the property, you can quickly and efficiently solve problems and update the private key corresponding to revoke property, when one or some of the properties of a user is revoked will still have access to other properties, and the revocation of a or some property does not affect the user's access to other users for this property, with a flexible, timely, fine-grained, high efficiency advantages revoke user attributes.