feat: allow plugging CMW into EAT submods

Signed-off-by: Thomas Fossati <[email protected]>

draft-ietf-rats-msg-wrap.md

@@ -301,10 +301,10 @@ For further security considerations about collections, see {{seccons-coll}}.
 ### Relation to EAT `submods`
 
 EAT submods ({{Section 4.2.18 of -rats-eat}}) provide a facility for aggregating attestation that has built-in security and will be suitable for some of the same attestation Evidence use cases covered by CMW collections.
-However, compared to CMW collections, EAT submods are limited in two ways:
 
-1. EAT {{-rats-eat}} allows carrying non-EAT-formatted types by augmenting the $EAT-CBOR-Tagged-Token socket or the $JSON-Selector socket. However, these need to be specified in subsequent standard documents updating the EAT specification,
-2. Their top-down structure does not align well with the bottom-up approach layered attesters use to build the chain of trust, making them not ideal for modelling layered attestation.
+However, compared to CMW collections, EAT submods are not ideal for modelling layered attestation because their top-down structure does not align well with the bottom-up approach layered attesters use to build the chain of trust.
+
+This specification (see {{submods}}) extends EAT to allow carrying CMW in EAT `submods`.
 
 ### CMW Collections' role in composite Attester topology
 
@@ -462,6 +462,25 @@ Section 6.1.8 of {{DICE-arch}} defines the ConceptualMessageWrapper format and t
 The CMW format defined in {{DICE-arch}} allows only a subset of the CMW grammar defined in this document.
 Specifically, the tunnel and collection formats cannot be encoded using DICE CMWs.
 
+# Transporting CMW in EAT `submods` {#submods}
+
+{{Section 4.2.18 of -rats-eat}} allows carrying non-EAT-formatted types in EAT submods by augmenting the `$EAT-CBOR-Tagged-Token` socket or the `$JSON-Selector` socket.
+
+The following CDDL adds `cbor-CMW` and `json-CMW` to EAT using such extension points:
+
+~~~ cddl
+$EAT-CBOR-Tagged-Token /= #6.CPA765(cbor-CMW)
+
+$JSON-Selector /= [ type: "CMW", nested-token: json-CMW ]
+~~~
+
+Where:
+
+* `cbor-CMW` and `json-CMW` are defined in {{collected-cddl}}, and
+* `CPA765` is the CBOR tag for CMW ({{iana-cbor-tag}}).
+
+[^rfced] This document uses the CPA (code point allocation) convention described in {{?I-D.bormann-cbor-draft-numbers}}. For each usage of the term "CPA", please remove the prefix "CPA" from the indicated value and replace the residue with the value assigned by IANA; perform an analogous substitution for all other occurrences of the prefix "CPA" in the document. Finally, please remove this note.
+
 # Examples
 
 The (equivalent) examples in {{ex-ja}}, {{ex-ca}}, and {{ex-ct}} assume that
@@ -663,13 +682,13 @@ IANA is requested to add a new `cmw` claim to the "JSON Web Token Claims" sub-re
 * Change Controller: IETF
 * Specification Document(s): {{type-n-val}} and {{cmw-coll}} of {{&SELF}}
 
-## CBOR Tag Registration
+## CBOR Tag Registration {#iana-cbor-tag}
 
 IANA is requested to add the following tag to the "CBOR Tags" {{!IANA.cbor-tags}} registry.
 
 | CBOR Tag | Data Item | Semantics | Reference |
 |----------|-----------|-----------|-----------|
-| TBD      | CBOR map, CBOR array, CBOR tag | RATS Conceptual Message Wrapper | {{type-n-val}}, {{cbor-tag}} and {{cmw-coll}} of {{&SELF}} |
+| CPA765 | CBOR map, CBOR array, CBOR tag | RATS Conceptual Message Wrapper | {{type-n-val}}, {{cbor-tag}} and {{cmw-coll}} of {{&SELF}} |
 
 ## RATS Conceptual Message Wrapper (CMW) Indicators Registry {#iana-ind-ext}
 
@@ -891,7 +910,7 @@ When using CMW collection, the preconditions apply for each entry in the collect
 The list of currently open issues for this documents can be found at
 [](https://github.com/thomas-fossati/draft-ftbs-rats-msg-wrap/issues).
 
-<cref>Note to RFC Editor: please remove before publication.</cref>
+[^rfced] please remove before publication.
 
 # Acknowledgments
 {:numbered="false"}