First step of authentication, done before the body is read: parses the MJDiag-Ed25519 header,
finds the Active registration for the install and requires the header keyId to be the
registered key. With unknownInstalls, an install in that cache is refused without a lookup,
and an install with no registration is added to it. A failed lookup is refused and not cached.
Failures are logged with their reason.
First step of authentication, done before the body is read: parses the
MJDiag-Ed25519header, finds the Active registration for the install and requires the headerkeyIdto be the registered key. WithunknownInstalls, an install in that cache is refused without a lookup, and an install with no registration is added to it. A failed lookup is refused and not cached. Failures are logged with their reason.