pub fn parse_header(
inner: &KeyChangeJws,
expected_url: &str,
) -> Result<InnerHeader, KeyChangeError>Expand description
Decodes and validates the inner JWS’s protected header (RFC 8555 §7.3.5
checks #3/#6): jwk must be present (guaranteed by InnerHeader’s shape
once it deserializes at all), and url must equal expected_url – the
outer JWS’s own already-verified header.url (RFC 8555 §6.4), i.e.
this exact keyChange request. No nonce check is made: RFC 8555
§7.3.5 requires the inner JWS to omit it entirely, and an extra field a
client sends anyway is silently ignored, like any unknown field the
payload types in this codebase accept.