
Abstract A traceable ciphertext-policy attribute-based encryption (T-CPABE) scheme can trace a malicious user, who may leak her/his decryption privilege to a third party for some benefits. However, even if the malicious user is traced, the existing schemes cannot revoke her/him from the cryptosystems. Thus, it is necessary to embed a revocation mechanism into a T-CPABE scheme in practice. In this paper, we propose a ciphertext-policy attribute-based encryption scheme with white-box traceability and direct user revocation. In the proposed scheme, the ciphertext is related to an access structure and a revocation list R . The secret key is associated with an attribute set and a user’s identity assigned a leaf node in a binary tree. The value of a leaf node is used to trace a malicious user. Once a malicious user is caught, her/his identity is added in the revocation list R . Only the ciphertext components associated with the revocation list R are updated according to the new revocation list R ′ , and the updated ciphertext can provide forward security. Therefore, a user can decrypt a ciphertext if and only if she/he is not in the revocation list and her/his attribute set satisfies the access policy, simultaneously. Furthermore, our scheme is proved to be secure under selective access policy and chosen-plaintext attacks based on the decisional q -bilinear Diffie–Hellman exponent hardness assumption in the standard model.
| selected citations These citations are derived from selected sources. This is an alternative to the "Influence" indicator, which also reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically). | 74 | |
| popularity This indicator reflects the "current" impact/attention (the "hype") of an article in the research community at large, based on the underlying citation network. | Top 1% | |
| influence This indicator reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically). | Top 10% | |
| impulse This indicator reflects the initial momentum of an article directly after its publication, based on the underlying citation network. | Top 10% |
