restructure document

draft-looker-oauth-jwt-cwt-status-list.md

@@ -39,7 +39,7 @@ The status list data structures themselves are also represented as JWTs or CWTs.
 
 JSON Web Tokens (JWTs) {{RFC7519}} and CBOR Web Tokens (CWTs) {{RFC8392}} as secure token formats, have vast possible applications. Some of these applications can involve issuing a token whereby certain semantics about the token can change over time, which are important to be able to communicate to relying parties in an interoperable manner, such as whether the token is considered invalidated or suspended by its issuer.
 
-This document defines Status List representations in JWT and CWT formats that describe the individual statuses of multiple Referenced Tokens, which themselves are also JWTs or CWTs. The statuses of all Referenced Tokens are conveyed via a bit array in the Status List. Each Referenced Token is allocated an index during issuance that represents its position within this bit array. The value of the bit(s) at this position correspond to the Referenced Token's status. The document also defines how an issuer of a Referenced Token references a Status List Token. Status Lists may be composed for expressing a range of Status Types. This document defines basic Status Types for the most common use cases as well as an extensibility mechanism for custom Status Types. The Status List Token may be used by an issuer in the Issuer-Holder-Verifier model to express the status of verifiable credentials (Referenced Tokens) issued by an issuer.
+This document defines Status List representations in JSON or CBOR formats and a Status List Token representation in JWT or CWT formats that describe the individual statuses of multiple Referenced Tokens, which themselves are also JWTs or CWTs. The statuses of all Referenced Tokens are conveyed via a bit array in the Status List. Each Referenced Token is allocated an index during issuance that represents its position within this bit array. The value of the bit(s) at this position correspond to the Referenced Token's status. The document also defines how an issuer of a Referenced Token references a Status List (Token). Status Lists may be composed for expressing a range of Status Types. This document defines basic Status Types for the most common use cases as well as an extensibility mechanism for custom Status Types. The Status List Token may be used by an issuer in the Issuer-Holder-Verifier model to express the status of verifiable credentials (Referenced Tokens) issued by an issuer.
 
 The following diagram depicts the basic conceptual relationship.
 
@@ -68,130 +68,35 @@ This specification seeks to find a balance between scalability, security, and pr
 # Terminology
 
 Status List:
-: A bit array that lists the statuses of many Referenced Tokens.
+: An object in JSON or CBOR representation containing a bit array that lists the statuses of many Referenced Tokens.
 
 Status List Token:
 : A token in JWT or CWT representation that contains a Status List.
 
 Referenced Token:
 : A token in JWT or CWT representation which contains a reference to a Status List Token. The information from the contained Status List may give a verifier additional information about up-to-date status of the Referenced Token.
 
-# JSON Web Token Representation
+# Status List
 
-## Status List JWT Format and Processing Requirements {#jwt-status-list-format-and-processing}
+## Status List Encoding {#status-list-base-encoding}
 
-The following rules apply to validating a JWT-based Status List Token. Application of additional restrictions and policy are at the discretion of the verifying party.
-
-1. The JWT MUST contain an "iss" (issuer) claim that contains a unique string identifier for the entity that issued the JWT. In the absence of an application profile specifying otherwise, compliant applications MUST compare issuer values using the Simple String Comparison method defined in Section 6.2.1 of {{RFC3986}}. The value MUST be equal to that of the "iss" claim contained within the Referenced Token.
-
-2. The JWT MUST contain a "sub" (subject) claim that contains an unique string identifier for that Referenced Token. The value MUST be equal to that of the "uri" claim contained in the "status" claim of the Referenced Token.
-
-3. The JWT MUST contain an "iat" (issued at) claim that identifies the time at which it was issued.
-
-4. The JWT MUST contain an "status_list" (status list) claim conforming to the rules outlined in [](#jwt-status-list-claim-format).
-
-5. The JWT MAY contain an "exp" (expiration time) claim that conveys when it is considered expired by its issuer.
-
-6. The JWT MAY contain other claims.
-
-7. The JWT MUST be digitally signed using an asymmetric cryptographic algorithm. Relying parties MUST reject the JWT if it is using a Message Authentication Code (MAC) algorithm. Relying parties MUST reject JWTs with an invalid signature.
-
-8. Relying parties MUST reject JWTs that are not valid in all other respects per "JSON Web Token (JWT)" {{RFC7519}}.
-
-~~~ ascii-art
-
-{
-  "typ": "statuslist+jwt",
-  "alg": "ES256",
-  "kid": "11"
-}
-.
-{
-  "iss": "https://example.com",
-  "sub": "https://example.com/statuslists/1",
-  "iat": 1683560915,
-  "exp": 1686232115,
-  "status_list": {
-    "bits": 1,
-    "lst": "H4sIAMo_jGQC_9u5GABc9QE7AgAAAA"
-  }
-}
-~~~
-
-### Status List Claim Format {#jwt-status-list-claim-format}
-
-The following rules apply to validating the "status_list" (status list) claim
-
-1. The claim value MUST be a valid JSON object.
-
-2. The claim value object MUST contain a "bits" (bit size) member with an numeric value that represents the number of bits per Referenced Token in the Status List ("lst") of the Status List JWT. The allowed values for "bits" are 1,2,4 and 8.
-
-3. The claim value object MUST contain a "lst" (list) member with a string value that represents the status values for all the tokens it conveys statuses for. The value MUST be computed using the algorithm described in [](#jwt-status-list-claim-encoding).
-
-### Status List Encoding {#jwt-status-list-claim-encoding}
+The following rules apply to the Status List:
 
 Each status of a Referenced Token MUST be represented with a bit size of 1,2,4, or 8. Therefore up to 2,4,16, or 256 statuses for a Referenced Token are possible, depending on the bit size. This limitation is intended to limit bit manipulation necessary to a single byte for every operation and thus keeping implementations simpler and less error prone.
 
 1. The overall Status List is encoded as a byte array. Depending on the bitsize, each byte corresponds to 8/(#bit-size) statuses (8,4,2, or 1). The status of each Referenced Token is identified using the index that maps to one or more specific bits within the byte array. The index starts counting at 0 and ends with "size" - 1 (being the last valid entry). The bits within an array are counted from least significant bit "0" to the most significant bit ("7"). All bits of the byte array at a particular index are set to a status value.
 
 2. The complete byte array is compressed using gZIP {{RFC1952}}.
 
-3. The result of the gZIP compression is then base64url-encoded, as defined in Section 2 of {{RFC7515}}.
+## Status List in JSON Format and Processing Requirements {#jwt-status-list-claim-format}
 
-## Referenced Token Format and Processing Requirements {#jwt-referenced-token}
-
-The following rules apply to validating a Referenced Token in JWT representation, which references a Status List Token. Application of additional restrictions and policy are at the discretion of the verifying party.
-
-1. The JWT MUST contain an "iss" (issuer) claim that contains a unique string identifier for the entity that issued the JWT. In the absence of an application profile specifying otherwise, compliant applications MUST compare issuer values using the Simple String Comparison method defined in Section 6.2.1 of {{RFC3986}}. The value MUST be equal to that of the "iss" claim contained within the referenced Status List Token.
-
-2. The JWT MUST contain an "status" (status) claim conforming to the rules outlined in [](#jwt-referenced-token-status)
-
-The following example is the decoded header and payload of a JWT meeting the processing rules as defined above.
-
-~~~ ascii-art
-
-{
-  "alg": "ES256",
-  "kid": "11"
-}
-.
-{
-  "iss": "https://example.com",
-  "status": {
-    "idx": 0,
-    "uri": "https://example.com/statuslists/1"
-  }
-}
-~~~
-
-### Status Claim Format {#jwt-referenced-token-status}
-
-The following rules apply to validating the "status" (status) claim
+The following rules apply to validating the "status_list" (status list) claim
 
 1. The claim value MUST be a valid JSON object.
 
-2. The claim value object MUST contain an "idx" (index) member with a numeric value that represents the index to check for status information in the Status List for the current JWT. The value of this member MUST be a non-negative number, containing a value of zero or greater.
-
-3. The claim value object MUST contain a "uri" member with a string value that identifies the Status List containing the status information for the JWT. The value of this member MUST be a uri conforming to {{RFC3986}}.
-
-# Status Types {#status-types}
-
-This document defines potential statuses of Referenced Tokens as Status Type values. If the Status List contains more than one bit per token (as defined by "bits" in the Status List), then the whole value of bits MUST describe one value. A Status List can not represent multiple statuses per Referenced Token.
-
-The registry in this document describes the basic Status Type values required for the most common use cases.
-Additional values may defined for particular use cases.
-
-## Status Types Values
-
-A status describes the state, mode, condition or stage of an entity that is described by the status list. Status Types MUST be numeric values between 0 and 255.
-Status types described by this specification comprise:
- - 0x00 - "VALID" - The status of the Token is valid, correct or legal.
- - 0x01 - "INVALID" - The status of the Token is revoked, annulled, taken back, recalled or cancelled. This state is irreversible.
- - 0x02 - "SUSPENDED" - The status of the Token is temporarily invalid, hanging, debarred from privilege. This state is reversible.
-
-The issuer of the Status List Token MUST choose an adequate "bits" (bit size) to be able to describe the required Status Types for the application.
+2. The claim value object MUST contain a "bits" (bit size) member with an numeric value that represents the number of bits per Referenced Token in the Status List ("lst") of the Status List JWT. The allowed values for "bits" are 1,2,4 and 8.
 
-# Example JWT Status Lists
+3. The claim value object MUST contain a "lst" (list) member with a string value that represents the status values for all the tokens it conveys statuses for. The value MUST be computed as the base64url-encoded result of the algorithm described in [](#status-list-base-encoding).
 
 ## Example Status List with 1-Bit Status Values
 
@@ -307,6 +212,103 @@ After compression and base64url encoding, the generated Status List is:
 }
 ~~~
 
+# Status List Token
+
+## Status List Token in JWT Format and Processing Requirements {#jwt-status-list-format-and-processing}
+
+The following rules apply to validating a JWT-based Status List Token. Application of additional restrictions and policy are at the discretion of the verifying party.
+
+1. The JWT MUST contain an "iss" (issuer) claim that contains a unique string identifier for the entity that issued the JWT. In the absence of an application profile specifying otherwise, compliant applications MUST compare issuer values using the Simple String Comparison method defined in Section 6.2.1 of {{RFC3986}}. The value MUST be equal to that of the "iss" claim contained within the Referenced Token.
+
+2. The JWT MUST contain a "sub" (subject) claim that contains an unique string identifier for that Referenced Token. The value MUST be equal to that of the "uri" claim contained in the "status" claim of the Referenced Token.
+
+3. The JWT MUST contain an "iat" (issued at) claim that identifies the time at which it was issued.
+
+4. The JWT MUST contain an "status_list" (status list) claim conforming to the rules outlined in [](#jwt-status-list-claim-format).
+
+5. The JWT MAY contain an "exp" (expiration time) claim that conveys when it is considered expired by its issuer.
+
+6. The JWT MAY contain other claims.
+
+7. The JWT MUST be digitally signed using an asymmetric cryptographic algorithm. Relying parties MUST reject the JWT if it is using a Message Authentication Code (MAC) algorithm. Relying parties MUST reject JWTs with an invalid signature.
+
+8. Relying parties MUST reject JWTs that are not valid in all other respects per "JSON Web Token (JWT)" {{RFC7519}}.
+
+~~~ ascii-art
+
+{
+  "typ": "statuslist+jwt",
+  "alg": "ES256",
+  "kid": "11"
+}
+.
+{
+  "iss": "https://example.com",
+  "sub": "https://example.com/statuslists/1",
+  "iat": 1683560915,
+  "exp": 1686232115,
+  "status_list": {
+    "bits": 1,
+    "lst": "H4sIAMo_jGQC_9u5GABc9QE7AgAAAA"
+  }
+}
+~~~
+
+# Referenced Token
+
+## Referenced Token in JWT Format and Processing Requirements {#jwt-referenced-token}
+
+The following rules apply to validating a Referenced Token in JWT representation, which references a Status List Token. Application of additional restrictions and policy are at the discretion of the verifying party.
+
+1. The JWT MUST contain an "iss" (issuer) claim that contains a unique string identifier for the entity that issued the JWT. In the absence of an application profile specifying otherwise, compliant applications MUST compare issuer values using the Simple String Comparison method defined in Section 6.2.1 of {{RFC3986}}. The value MUST be equal to that of the "iss" claim contained within the referenced Status List Token.
+
+2. The JWT MUST contain an "status" (status) claim conforming to the rules outlined in [](#jwt-referenced-token-status)
+
+The following example is the decoded header and payload of a JWT meeting the processing rules as defined above.
+
+~~~ ascii-art
+
+{
+  "alg": "ES256",
+  "kid": "11"
+}
+.
+{
+  "iss": "https://example.com",
+  "status": {
+    "idx": 0,
+    "uri": "https://example.com/statuslists/1"
+  }
+}
+~~~
+
+### Status Claim Format {#jwt-referenced-token-status}
+
+The following rules apply to validating the "status" (status) claim
+
+1. The claim value MUST be a valid JSON object.
+
+2. The claim value object MUST contain an "idx" (index) member with a numeric value that represents the index to check for status information in the Status List for the current JWT. The value of this member MUST be a non-negative number, containing a value of zero or greater.
+
+3. The claim value object MUST contain a "uri" member with a string value that identifies the Status List containing the status information for the JWT. The value of this member MUST be a uri conforming to {{RFC3986}}.
+
+# Status Types {#status-types}
+
+This document defines potential statuses of Referenced Tokens as Status Type values. If the Status List contains more than one bit per token (as defined by "bits" in the Status List), then the whole value of bits MUST describe one value. A Status List can not represent multiple statuses per Referenced Token.
+
+The registry in this document describes the basic Status Type values required for the most common use cases.
+Additional values may defined for particular use cases.
+
+## Status Types Values
+
+A status describes the state, mode, condition or stage of an entity that is described by the status list. Status Types MUST be numeric values between 0 and 255.
+Status types described by this specification comprise:
+- 0x00 - "VALID" - The status of the Token is valid, correct or legal.
+- 0x01 - "INVALID" - The status of the Token is revoked, annulled, taken back, recalled or cancelled. This state is irreversible.
+- 0x02 - "SUSPENDED" - The status of the Token is temporarily invalid, hanging, debarred from privilege. This state is reversible.
+
+The issuer of the Status List Token MUST choose an adequate "bits" (bit size) to be able to describe the required Status Types for the application.
+
 # CWT Representations
 
 TBD Define parallel CWT representations for Status Lists and Referenced Tokens.