Field DeclaredType

Namespace

MailFathom.Common.ClientAssertions

Assembly

MailFathom.Common.dll

The media type an assertion declares in its typ header, which is what a MailFathom credential is recognized by.

public const string DeclaredType = "mailfathom-client-assertion+jwt"

Returns

string

The media type an assertion declares in its typ header, which is what a MailFathom credential is recognized by.

Remarks

RFC 8725 section 3.11 asks for explicit typing wherever a deployment reads more than one kind of JSON Web Token, and this endpoint reads two: an access token an authorization server issued, and an assertion a client minted for itself. Declaring the type is what keeps one from ever being judged by the other's rules — an access token cannot be presented as an assertion, and an assertion cannot be replayed at an authorization server as anything.

The name is MailFathom's own rather than a registered media type, because nothing outside this deployment and its own clients ever reads it. It is stated in full — with the +jwt structural suffix RFC 8417 established for exactly this — so a value that reaches a log or a diagnostic says what it is.