AttestationChallenge

The issuing time of the nonce. Useful to detect clock drifts and exit early. This is not considered sensible information, as clocks must be in sync anyhow.

How long this nonce is considered valid.

The server timezone. Purely diagnostic, since the Instant used for issuedAt is UTC by definition. Can be omitted if the server does not want to disclose this information

The nonce chosen by the server. Must be at most 128 bytes long, as this is the largest nonce size supported by Android.

The endpoint to post the CSR containing the attestation proof to.

The OID to be used for encoding the attestation proof into the signed CSR used to transfer the proof.

Whether to include a generic make and model (such as "Google Pixel 8", or "iPhone 16" with the attestation proof). Setting this to an OID other than null will include a device name on a best-effort basis. Defaults to null (i.e., no device name will be included).

Specifies key constraints for the client.

Optional user-defined payload. See additionalPayload for serialization requirements.

Optional runtime-only attachment. Not serialized and excluded from equality/hashing.

in case the nonce is larger than 128 bytes