De-duplication of encrypted data
AssigneeNokia Technologies Oy
InventorZheng Yan
Life of this patent
Estimating the term…
Abstract
According to an example aspect of the invention, there is provided an apparatus comprising at least one processing core and at least one memory including computer program code, the at least one memory and the computer program code being configured to, with the at least one processing core, cause the apparatus at least to receive, from a first user, a ciphertext, a first hash value and a first ciphered encryption key, receive, from a second user, a second hash value, responsive to a determination the first hash value is the same as the second hash value, obtain a re-encryption key, and apply the re-encryption key to the first ciphered encryption key to obtain a re-encrypted encryption key, the re-encrypted encryption key being decryptable with a secret key of the second user.
Claims20
An apparatus comprising at least one processing core and at least one memory including computer program code, the at least one memory and the computer program code being configured to, with the at least one processing core, cause the apparatus at least to:
- receive, from a first user, a ciphertext, a first hash value and a first encrypted encryption key, the received first encryption key being encrypted using a public key of a second apparatus which is distinct from the apparatus, the apparatus not storing a key capable of decrypting the first encrypted encryption key;
- receive, from a second user, a second hash value;
- responsive to a determination the first hash value is the same as the second hash value, obtain a re-encryption key generated using a proxy re-encryption key generation algorithm, and
- apply the re-encryption key to the first encrypted encryption key to obtain a re-encrypted encryption key, the re-encrypted encryption key being decryptable with a secret key of the second user, wherein in obtaining the re-encrypted encryption key from the received encrypted key, the apparatus does not decrypt the first encrypted encryption key.
A method comprising:
- receiving, in an apparatus, from a first user, a ciphertext, a first hash value and a first encrypted encryption key, the received first encryption key being encrypted using a public key of a second apparatus which is distinct from the apparatus, an apparatus performing the method not storing a key capable of decrypting the first encrypted encryption key;
- receiving, from a second user, a second hash value;
- responsive to a determination the first hash value is the same as the second hash value, obtaining a re-encryption key generated using a proxy re-encryption key generation algorithm, and
- applying the re-encryption key to the first encrypted encryption key to obtain a re-encrypted encryption key, the re-encrypted encryption key being decryptable with a secret key of the second user, wherein in obtaining the re-encrypted encryption key from the received encrypted key, the apparatus does not decrypt the first encrypted encryption key.
A non-transitory computer readable medium having stored thereon a set of computer readable instructions that, when executed by at least one processor, cause an apparatus to at least:
- receive, in an apparatus, from a first user, a ciphertext, a first hash value and a first encrypted encryption key, the received first encryption key being encrypted using a public key of a second apparatus which is distinct from the apparatus, the apparatus not storing a key capable of decrypting the first encrypted encryption key;
- receive, from a second user, a second hash value;
- responsive to a determination the first hash value is the same as the second hash value, obtain a re-encryption key generated using a proxy re-encryption key generation algorithm, and
- apply the re-encryption key to the first encrypted encryption key to obtain a re-encrypted encryption key, the re-encrypted encryption key being decryptable with a secret key of the second user, wherein in obtaining the re-encrypted encryption key from the received encrypted key, the apparatus does not decrypt the first encrypted encryption key.
Dependencies are inferred from the claim text.