Patent attributes
A system and method for sharing an encrypted file stored on a cloud server is disclosed. In certain embodiments, the method includes generating a file key associated with the encrypted file stored in the cloud server; generating a share message, the share message including the generated file key and identifying a recipient user and the encrypted file stored in the cloud server; encrypting the file key using an identification key of the recipient user to generate a share key; storing the share key in the cloud server; notifying the recipient user of the encrypted file and share key stored on the cloud server; retrieving the encrypted file and the share key from the cloud server; decrypting the share key using the identification key of the recipient user to reconstruct the file key; and using the reconstructed file key to decrypt the encrypted file.