Abstract: Apparatuses, systems, methods, and software are disclosed for authorization delegation. In a participant device a derivative key is generated in dependence on a received key. An authenticity check value for a delegation information block is generated in dependence on the delegation information block and the received key. The derivative key is derived in dependence on the delegation information block and the received key. An extended certificate chain is created comprising a received certificate chain appended with a local certificate, which comprises the delegation information block and the authenticity check value.

Abstract: Aspects of the present disclosure relate to an apparatus comprising secure enclave circuitry and document owner circuitry. The document owner circuitry is configured to determine a document to be shared, generate a plurality of share data units, transmit each share data unit of the plurality of share data units to a corresponding shareholder device, and provision the secure enclave circuitry with data indicative of the document to be shared. The secure enclave circuitry is configured to receive putative share data units from at least one of the corresponding shareholder devices, determine whether the received putative share data units satisfy a sharing policy, and responsive to the received putative share data units satisfying the sharing policy and based on the data indicative of the document to be shared, provide the document to be shared to said at least one of the corresponding shareholder devices.

Abstract: There is provided a data processing system and method. The system includes challenge circuitry for issuing a challenge to a service device and for receiving a response to the challenge. Forwarding circuitry forwards at least part of the response to a selected one of a plurality of attestation systems and receives a success indication from the selected one of the plurality of attestation systems regarding whether the service device has been attested by the selected one of the plurality of attestation systems. Request circuitry receives a request to provide an attestation of the service device, and to provide the attestation in dependence on the success indication.

Abstract: Apparatuses, systems, methods, and software are disclosed for authorization delegation. In a participant device a derivative key is generated in dependence on a received key. An authenticity check value for a delegation information block is generated in dependence on the delegation information block and the received key. The derivative key is derived in dependence on the delegation information block and the received key. An extended certificate chain is created comprising a received certificate chain appended with a local certificate, which comprises the delegation information block and the authenticity check value.