device-identity-provisioning: add keypair discovery and rename to Att…

specifications/device-identity-provisioning/cddl/attested-csr-eat.cddl

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+; An Attested CSR EAT is one of two variants:
+;   - A CSR response, returned for a specific KeyPairID > 0.
+;   - A keypair-inventory (discovery) response, returned when the
+;     Requester specifies KeyPairID = 0.
+cwt-attested-csr-eat =
+  cwt-attested-csr-eat-csr /
+  cwt-attested-csr-eat-inventory
+
+cwt-attested-csr-eat-csr = {
+  ; Nonce claim is nonce-type = bstr .size (8..64)
+  &(nonce : 10) => bstr
+
+  ; Private Claims (they have to be < -65536 for rfc8392)
+
+  ; CSR bytestring
+  &(csr: -70001) => bstr
+
+  ; Derivation attributes, expressed as an OID -> bitfield map
+  &(attrib: -70002) => key-attributes-map
+}
+
+; Discovery response payload returned when KeyPairID = 0 in the request.
+cwt-attested-csr-eat-inventory = {
+  ; Nonce claim is nonce-type = bstr .size (8..64)
+  &(nonce : 10) => bstr
+
+  ; KeyPair Inventory private claim. Each entry pairs a KeyPairID
+  ; with the derivation-attribute bitfield map that applies to it.
+  &(keypair-inventory: -70003) => [+ keypair-inventory-entry]
+}
+
+keypair-inventory-entry = [
+  keypair-id: 1..255,
+  attributes: key-attributes-map
+]
+
+; Derivation attributes are expressed as a map from an OID to a
+; bitfield. The OCP OID (ocp-security-dip-kda) is REQUIRED and maps to
+; the OCP derivation-component bitfield. Vendors MAY add additional
+; OIDs mapping to vendor-specific bitfields for derivation components
+; not covered by the OCP bitfield.
+key-attributes-map = {
+  ocp-security-dip-kda => ocp-derivation-bitfield
+  * tagged-oid-type => uint
+}
+
+; Tagged OID per RFC 9090.
+tagged-oid-type = #6.111(bstr)
+
+; OID 1.3.6.1.4.1.42623.1.2 (ocp-security-dip-kda).
+ocp-security-dip-kda = #6.111(h'2B0601040182CC7F0102')
+
+; OCP derivation-component bitfield. A set bit indicates that the
+; corresponding component contributed to the keypair's derivation.
+ocp-derivation-bitfield = uint .bits ocp-derivation-components
+
+ocp-derivation-components = &(
+  UDS: 0,
+  FIELD_ENTROPY: 1,
+  OWNER_PROVISIONED_NON_CONFIDENTIAL_FUSE: 2,
+  VENDOR_PROVISIONED_NON_CONFIDENTIAL_FUSE: 3,
+  FIRST_MUTABLE_CODE: 4,
+  RUNTIME_FIRMWARE: 5,
+)
+
+signed-cwt = #6.18(COSE-Sign1-attested-csr)
+
+COSE-Sign1-attested-csr = [
+  protected: bstr .cbor protected-header-map
+  unprotected: {}
+  payload: bstr .cbor cwt-attested-csr-eat
+  signature: bstr
+]
+
+protected-header-map = {
+  &(alg-id: 1) => int
+  &(content-type: 3) => tstr / int
+  &(issuer-key-id: 4) => bstr
+}
+

specifications/device-identity-provisioning/diag/attested-csr-eat-example.diag

@@ -0,0 +1,74 @@
+; ----------------------------------------------------------------------
+; Example: CSR response (returned when the Requester sent
+; GET_ATTESTED_CSR with a specific KeyPairID > 0). The payload
+; carries the CSR for the selected keypair along with the derivation-
+; attribute bitfield map that applies to it.
+; ----------------------------------------------------------------------
+
+signed-cwt / 18([
+  / protected / <<{
+    / alg-id / 1 : 7,
+    / content-type / 3 : "application/eat+cbor",
+    ; SHA-384 hash of the Attestation Key's certificate chain (same as
+    ; the SPDM DIGEST response) for the slot that produced this signature.
+    / kid / 4 : h'1a2b3c4d5e6f70819203a4b5c6d7e8f900112233445566778899aabbccddeeff00112233445566778899aabbccddeeff'
+  }>>,
+  / unprotected / {},
+/ payload / <<{
+      / nonce / 10: h'AAAABBBBCCCCDDDDEEEEFFFF0000111122223333444455556666777788889999', 
+      / csr / -70001 :  h'59025630820252308201d9a003020102021431a4e0',
+      ; Derivation attributes as an OID -> bitfield map. The single OCP
+      ; OID (1.3.6.1.4.1.42623.1.2) maps to the OCP bitfield. This CSR is
+      ; for the LDevID keypair (KeyPairID 2 in the discovery example):
+      ; UDS(bit 0) | FIELD_ENTROPY(bit 1) = 3
+      / attrib / -70002: {
+        111(h'2B0601040182CC7F0102') : 3
+      }
+  }>>,
+  / signature / h'FA45AAB345AB4988' 
+])
+
+; ----------------------------------------------------------------------
+; Example: discovery response (returned when the Requester sent
+; GET_ATTESTED_CSR with KeyPairID = 0). The payload omits the
+; CSR/attrib claims and instead carries the KeyPair Inventory claim,
+; which enumerates every supported KeyPairID and its derivation-
+; attribute bitfield map.
+; ----------------------------------------------------------------------
+
+signed-cwt / 18([
+  / protected / <<{
+    / alg-id / 1 : 7,
+    / content-type / 3 : "application/eat+cbor",
+    ; SHA-384 hash of the Attestation Key's certificate chain (same as
+    ; the SPDM DIGEST response) for the slot that produced this signature.
+    / kid / 4 : h'1a2b3c4d5e6f70819203a4b5c6d7e8f900112233445566778899aabbccddeeff00112233445566778899aabbccddeeff'
+  }>>,
+  / unprotected / {},
+  / payload / <<{
+      / nonce / 10 : h'AAAABBBBCCCCDDDDEEEEFFFF0000111122223333444455556666777788889999',
+      / keypair-inventory / -70003 : [
+        ; Each entry: [ KeyPairID, { OCP OID : bitfield } ].
+        ; The single OCP OID is 1.3.6.1.4.1.42623.1.2.
+        ; Bitfields are cumulative: each key's bitfield includes the
+        ; derivation components inherited from its ancestor keys.
+        ; KeyPairID 1: IDevID, derived from UDS.
+        ; UDS(bit 0) = 1
+        [ 1, {
+            111(h'2B0601040182CC7F0102') : 1
+        } ],
+        ; KeyPairID 2: LDevID, derived from IDevID + Field Entropy.
+        ; UDS(bit 0) | FIELD_ENTROPY(bit 1) = 3
+        [ 2, {
+            111(h'2B0601040182CC7F0102') : 3
+        } ],
+        ; KeyPairID 3: derived from Owner-provisioned alias key +  Field Entropy + UDS.
+        ; UDS(bit 0) | FIELD_ENTROPY(bit 1) |
+        ;   OWNER_PROVISIONED_NON_CONFIDENTIAL_FUSE(bit 2) = 7
+        [ 3, {
+            111(h'2B0601040182CC7F0102') : 7
+        } ]
+      ]
+  }>>,
+  / signature / h'FA45AAB345AB4988'
+])