ASN.1 module Ieee1609Dot2Dot1AcaEeInterface

OID: {iso(1) identified-organization(3) ieee(111) standards-association-numbered-series-standards(2) wave-stds(1609) dot2(2) extension-standards(255) dot1(1) interfaces(1) aca-ee(1) major-version-2(2) minor-version-4(4)}

Imports:

• Ieee1609Dot2 {iso(1) identified-organization(3) ieee(111) standards-association-numbered-series-standards(2) wave-stds(1609) dot2(2) base(1) schema(1) major-version-2(2) minor-version-5(5)} WITH SUCCESSORS
  
• Ieee1609Dot2BaseTypes {iso(1) identified-organization(3) ieee(111) standards-association-numbered-series-standards(2) wave-stds(1609) dot2(2) base(1) base-types(2) major-version-2(2) minor-version-3(3)} WITH SUCCESSORS
  

Data Elements:

AcaEeInterfacePdu

This is the parent structure for all structures exchanged between the ACA and the EE. The ACA - EE interface is a logical interface rather than a direct communications interface in that there is no direct message flow between the ACA and the EE: Messages from the ACA are stored by the RA and subsequently forwarded to the EE. The PDUs are identified as ACA-EE PDUs even though the RA acts as a forwarder for them because those PDUs are created by the ACA and encrypted for the EE, and not modified and frequently not read by the RA. An overview of this structure is as follows:

• acaEeCertResponse of type AcaEeCertResponse
  contains the ACA's response to RaAcaCertRequestSPDU, which is meant for the EE and sent via the RA.

AcaEeInterfacePdu ::= CHOICE {
  acaEeCertResponse  AcaEeCertResponse,
  ...
}

AcaEeCertResponse

This structure contains a certificate and associated data as generated by the ACA for the EE that will be the holder of that certificate. An overview of this structure is as follows:

• version of type Uint8 (2)
  contains the current version of the structure.

• generationTime of type Time32
  contains the generation time of AcaEeCertResponse.

• certificate of type Certificate
  contains an authorization certificate generated by the ACA. It is of the type indicated by the type field in the corresponding request (if the requester requested an incorrect type, the response would be an error not an instance of this structure).

• privateKeyInfo of type OCTET STRING (SIZE (32)) OPTIONAL
  shall be:

  1. Present and contain the private key randomization value, if the field certificate.type is explicit and the butterfly key mechanism was used to generate the certificate. This is used by the EE in deriving the butterfly private key for explicit certificates as specified in 9.3.
  2. Present and contain the private key reconstruction value, if the field certificate.type is implicit. This is used by the EE as specified in 5.3.2 of IEEE Std 1609.2a-2017 (also 9.3 if the butterfly key mechanism is used).
  3. Absent otherwise.

NOTE: In the case where the butterfly expansion function is used to set certEncKey in RaAcaCertRequest, the value j is not communicated to the ACA. However, the EE that receives the certificate response can only decrypt the response if it knows j. The RA is therefore anticipated to store j so that it can be associated with the appropriate certificate response. The RA encodes j in the filename.

AcaEeCertResponse ::= SEQUENCE {
  version         Uint8 (2),
  generationTime  Time32,
  certificate     Certificate,
  privateKeyInfo  OCTET STRING (SIZE (32)) OPTIONAL,
  ...
}