Opaque Service Key mapping with SvcKeyMud chunks

Service Key Mud is an opaque service key.

This is a key introduction chunk that requires an interaction with the KIP Service to retrieve the key. That interaction involves the local user's authentication. Effectively, the user identity is keyed by this interaction, hence the name KIP which means Keyful Identity Protocol.

Authentication is done over SASL, and it may cause popups, or rely on agents that provide the requested keys. This element of desktop integration is not part of the KIP Document design, but is delegated to the underlying KIP Service client libaries.

Code: Creation of a SvcKeyMud uses the C-API format, and is simply

svckeymud = SvcKeyMud (b'\x1a...\xa1')

The byte string can be made with the key_fromservice() call on the KIP core Context object.

CBOR: The format in KIP Document for this chunk is simply an array with tag 8 for SvcKeyMud and the binary content from the C-API:

[ 8, "\x1a..\xa1" ]