  As advanced V2X applications emerge in the connected and autonomous vehicle
(CAV), the data communications between in-vehicle end-devices and outside nodes
increase, which make the end-to-end (E2E) security to in-vehicle end-devices as
the urgent issue to be handled. However, the E2E security with fine-grained
access control still remains as a challenging issue for resource-constrained
end-devices since the existing security solutions require complicated key
management and high resource consumption. Therefore, we propose a practical and
secure vehicular communication protocol for the E2E security based on a new
attribute-based encryption (ABE) scheme. In our scheme, the outsourced
computation is provided for encryption, and the computation cost for decryption
constantly remains small, regardless of the number of attributes. The policy
privacy can be ensured by the proposed ABE to support privacy-sensitive V2X
applications, and the existing identity-based signature for outsourced signing
is newly reconstructed. Our scheme achieves the confidentiality, message
authentication, identity anonymity, unlinkability, traceability, and
reconfigurable outsourced computation, and we also show the practical
feasibility of our protocol via the performance evaluation.
