| Internet-Draft | RARE | July 2026 |
| Fossati, et al. | Expires 4 January 2027 | [Page] |
This document describes a set of REST APIs that can be used by RATS roles to interact. These APIs facilitate the discovery of a role's capabilities, as well as the negotiation and exchange of RATS Conceptual Messages in several key scenarios, including Evidence gathering, Evidence appraisal, Endorsements and Reference Value management. This document aims to present a useful subset of possible RATS interaction patterns, rather than covering all of them.¶
This note is to be removed before publishing as an RFC.¶
The latest revision of this draft can be found at https://thomas-fossati.github.io/rare/draft-fossati-rats-rare.html. Status information for this document may be found at https://datatracker.ietf.org/doc/draft-fossati-rats-rare/.¶
Discussion of this document takes place on the Remote ATtestation ProcedureS Working Group mailing list (mailto:rats@ietf.org), which is archived at https://mailarchive.ietf.org/arch/browse/rats/. Subscribe at https://www.ietf.org/mailman/listinfo/rats/.¶
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TODO Introduction¶
Section 3 describes APIs for the appraisal of Evidence. Section 4 describes APIs for Endorsements and Reference Values management. Section 5 describes APIs for requesting Evidence from a (composite) Attester, together with a data format for aggregating composite Evidence based on Collection CMWs [I-D.ietf-rats-msg-wrap]. The Evidence appraisal and Evidence request APIs are both based on the challenge-response interaction model described in Section 7.1 of [I-D.ietf-rats-reference-interaction-models].¶
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here.¶
TODO Security¶
TODO IANA¶
=============== NOTE: '\' line wrapping per RFC 8792 ================
cat-token = #6.18([
protected: bytes .cbor phdrs,
unprotected: uhdrs,
payload: bytes .cbor cat-collection,
signature: bytes,
])
phdrs = {
? &(x5chain: 33) => bytes / [2*certs: bytes],
* cose.label => cose.values,
}
uhdrs = {* cose.label => cose.values}
cat-collection = {
"__cmwc_t" => RATSD-CMWCT,
"__ratsd" => [
RATSD-CLAIMS-MEDIATYPE,
bytes .cbor ratsd-claims,
],
+ text => cmw.cbor-record,
}
RATSD-CLAIMS-PROFILE = "tag:github.com,2026:veraison/ratsd/v2"
ratsd-claims = #6.601({
&(eat_profile: 265) => RATSD-CLAIMS-PROFILE,
&(eat_nonce: 10) => bytes .size (8 .. 64),
&(oemid: 258) => eat.oemid-pen / eat.oemid-ieee / eat.oemid-\
random,
&(sw-name: 270) => text,
&(sw-version: 271) => eat.sw-version-type,
? (
&(nonce_adjust_function: -65537) => \
nonce_adjust_function_type,
&(nonce_adjust_map: -65538) => {+ text => uint},
),
})
nonce_adjust_function_type /= "shake-128" / "shake-256"
RATSD-CLAIMS-MEDIATYPE = ("application/eat-ucs+cbor; eat_profile=\"\
" .cat RATSD-CLAIMS-PROFILE) .cat "\""
RATSD-CMWCT = "tag:github.com,2025:veraison/ratsd/cmw/v2"
cose.label = int / tstr
cose.values = any
cbor-record = cmw.cbor-record
cmw.cbor-record = [
type: cmw.coap-content-format-type / cmw.media-type,
value: bytes,
? ind: uint .bits cmw.cm-type,
]
cmw.coap-content-format-type = uint .size 2
cmw.media-type = text .abnf ("Content-Type" .cat cmw.Content-Type-\
ABNF)
cmw.cm-type = &(
reference-values: 0,
endorsements: 1,
evidence: 2,
attestation-results: 3,
appraisal-policy: 4,
)
cmw.Content-Type-ABNF = '
Content-Type = Media-Type-Name *( *SP ";" *SP parameter )
parameter = token "=" ( token / quoted-string )
token = 1*tchar
tchar = "!" / "#" / "$" / "%" / "&" / "\'" / "*"
/ "+" / "-" / "." / "^" / "_" / "`" / "|" / "~"
/ DIGIT / ALPHA
quoted-string = %x22 *( qdtext / quoted-pair ) %x22
qdtext = SP / %x21 / %x23-5B / %x5D-7E
quoted-pair = "\\" ( SP / VCHAR )
Media-Type-Name = type-name "/" subtype-name
type-name = restricted-name
subtype-name = restricted-name
restricted-name = restricted-name-first *126restricted-name-chars
restricted-name-first = ALPHA / DIGIT
restricted-name-chars = ALPHA / DIGIT / "!" / "#" /
"$" / "&" / "-" / "^" / "_"
restricted-name-chars =/ "." ; Characters before first dot always
; specify a facet name
restricted-name-chars =/ "+" ; Characters after last plus always
; specify a structured syntax suffix
DIGIT = %x30-39 ; 0 - 9
POS-DIGIT = %x31-39 ; 1 - 9
ALPHA = %x41-5A / %x61-7A ; A - Z / a - z
SP = %x20
VCHAR = %x21-7E ; printable ASCII (no SP)
'
sw-version-type = eat.sw-version-type
eat.sw-version-type = [
version: tstr,
? scheme: $version-scheme,
]
eat.oemid-pen = int
eat.oemid-ieee = eat.JC<eat.oemid-ieee-json, eat.oemid-ieee-cbor>
eat.oemid-random = eat.JC<eat.oemid-random-json, eat.oemid-random-\
cbor>
eat.JC<J, C> = eat.JSON-ONLY<J> / eat.CBOR-ONLY<C>
eat.JSON-ONLY<J> = J .feature "json"
eat.CBOR-ONLY<C> = C .feature "cbor"
eat.oemid-ieee-json = tstr .b64u eat.oemid-ieee-cbor
eat.oemid-ieee-cbor = bstr .size 3
eat.oemid-random-json = tstr .b64u eat.oemid-random-cbor
eat.oemid-random-cbor = bstr .size 16
oemid-pen = eat.oemid-pen
oemid-ieee = eat.oemid-ieee
oemid-random = eat.oemid-random
¶
TODO openapi¶
The APIs described in this document were designed and prototyped as part of the Veraison project over the past few years. The authors would like to thank the Veraison community, and in particular Dhanus M Lal, Ding Ma, Ian Chin Wang, Ian Oliver, Jag Raman, Sergei Trofimov, Shefali Kamal, Simon Frost and Yogesh Deshpande, for their invaluable contributions.¶