+Like Javascript Object Notation (JSON) [[RFC8259]], Concise Binary Object Representation (CBOR) [[RFC7049]] +defines a set of formatting rules for the portable representation of structured data. CBOR is a more concise, machine-readable, language-independent data interchange format that is self-describing and has built-in semantics for interoperability. With specific constraints, CBOR can support all JSON data types (including JSON-LD) for translation between the DID document model (described in Data Model and DID Documents) and other core representations. +
+ +Concise Data Definition Language (CDDL) [[RFC8610 ]] is a notation used to express Concise Binary Object Representation (CBOR), and by extension JSON Data Structures. The following notation expresses the DID Document model in CBOR representation with specific constraints for deterministic mappings between other core representations.
+ +
+ DID-document = {
+ ? @context : uri
+ id : did
+ ? publicKey : [* publicKey ]
+ ? authentication : [ *did // *publicKey // *tstr ]
+ ? service : [ + service ]
+ ? controller : did / [ *did ]
+ ? created : time
+ ? updated : time
+ proof : any
+ }
+
+ publicKey = {
+ id : did
+ type : text
+ controller : uri
+ }
+
+ did = tstr .pcre "^did\\:(?[a-z0-9]{2,})\\:(?[A-Za-z0-9\\.\\-\\:\\_]+)"
+
+ did-url = tstr .pcre "^did\\:(?[a-z0-9]{2,})\\:(?[A-Za-z0-9\\.\\-\\:\\_]+)\\;(?[A-Za-z0-9\\/)(?\\?[a-z0-9\\=\\&])#(?.+)"
+
+ service = {
+ id : did-url
+ type : text
+ serviceEndpoint : uri
+ ? description : text
+ * tstr => any
+ }
+
+
+ When producing DID Documents that are represented as CBOR, in addition to the suggestions in section 3.9 of the CBOR [[RFC7049]] specification for deterministic mappings, the following constraints of the DID Document model MUST be followed:
+ ++ a7 # map(7) + 62 # text(2) + 6964 # "id" + 78 40 # text(64) + 6469643a6578616d706c653a31324433 # "did:example:12D3" + 4b6f6f574d4864727a6377706a626472 # "KooWMHdrzcwpjbdr" + 5a733547477145524176636771583362 # "Zs5GGqERAvcgqX3b" + 3564707550745061396f743639796577 # "5dpuPtPa9ot69yew" + 65 # text(5) + 70726f6f66 # "proof" + a4 # map(4) + 64 # text(4) + 74797065 # "type" + 74 # text(20) + 656432353531395369676e617475726532303138 # "ed25519Signature2018" + 67 # text(7) + 63726561746564 # "created" + 74 # text(20) + 323032302d30352d30315430333a30303a30325a # "2020-05-01T03:00:02Z" + 67 # text(7) + 63726561746f72 # "creator" + 78 8c # text(140) + 6469643a6578616d706c653a31324433 # "did:example:12D3" + 4b6f6f574d4864727a6377706a626472 # "KooWMHdrzcwpjbdr" + 5a733547477145524176636771583362 # "Zs5GGqERAvcgqX3b" + 3564707550745061396f743639796577 # "5dpuPtPa9ot69yew" + 3b206578616d706c653a6b65793d6964 # "; example:key=id" + 3d626166797265696375627478357771 # "=bafyreicubtx5wq" + 6f336e6f73633463617a726b63746668 # "o3nosc4cazrkctfh" + 776436726577657a6770776f65347377 # "wd6rewezgpwoe4sw" + 69726c733465626468733269 # "irls4ebdhs2i" + 6e # text(14) + 7369676e617475726556616c7565 # "signatureValue" + 78 58 # text(88) + 6f3972364c78676f474e38466f616565 # "o9r6LxgoGN8Foaee" + 554136456444637631324776447a4645 # "UA6EdDcv12GvDzFE" + 6d43676a577a76707572325953517941 # "mCgjWzvpur2YSQyA" + 3857327230535357554b2b6e4835744d # "8W2r0SSWUK+nH5tM" + 717a61464c756e3677775a31456f7433 # "qzaFLun6wwZ1Eot3" + 37616d4744673d3d # "7amGDg==" + 67 # text(7) + 63726561746564 # "created" + 74 # text(20) + 323031382d31322d30315430333a30303a30305a # "2018-12-01T03:00:00Z" + 67 # text(7) + 75706461746564 # "updated" + 74 # text(20) + 323032302d30352d30315430333a30303a30305a # "2020-05-01T03:00:00Z" + 68 # text(8) + 40636f6e74657874 # "@context" + 78 1c # text(28) + 68747470733a2f2f7777772e77332e6f # "https://www.w3.o" + 72672f6e732f6469642f7631 # "rg/ns/did/v1" + 69 # text(9) + 7075626c69634b6579 # "publicKey" + 81 # array(1) + a5 # map(5) + 62 # text(2) + 6964 # "id" + 78 85 # text(133) + 6261667972656963756274783577716f # "bafyreicubtx5wqo" + 336e6f73633463617a726b6374666877 # "3nosc4cazrkctfhw" + 6436726577657a6770776f6534737769 # "d6rewezgpwoe4swi" + 726c7334656264687332693b6578616d # "rls4ebdhs2i;exam" + 706c653a6b65793d6964626166797265 # "ple:key=idbafyre" + 6963756274783577716f336e6f736334 # "icubtx5wqo3nosc4" + 63617a726b6374666877643672657765 # "cazrkctfhwd6rewe" + 7a6770776f6534737769726c73346562 # "zgpwoe4swirls4eb" + 6468733269 # "dhs2i" + 64 # text(4) + 74797065 # "type" + 6e # text(14) + 45644473615075626c69634b6579 # "EdDsaPublicKey" + 65 # text(5) + 6375727665 # "curve" + 67 # text(7) + 65643235353139 # "ed25519" + 67 # text(7) + 65787069726573 # "expires" + 74 # text(20) + 323031392d31322d30315430333a30303a30305a # "2019-12-01T03:00:00Z" + 6f # text(15) + 7075626c69634b6579426173653634 # "publicKeyBase64" + 78 2c # text(44) + 716d7a3774704c4e4b4b4b646c376344 # "qmz7tpLNKKKdl7cD" + 375062656a4469425670374f4e706d5a # "7PbejDiBVp7ONpmZ" + 62666d633763454b396d673d # "bfmc7cEK9mg=" + 6e # text(14) + 61757468656e7469636174696f6e # "authentication" + 81 # array(1) + 78 83 # text(131) + 6469643a6578616d706c653a31324433 # "did:example:12D3" + 4b6f6f574d4864727a6377706a626472 # "KooWMHdrzcwpjbdr" + 5a733547477145524176636771583362 # "Zs5GGqERAvcgqX3b" + 3564707550745061396f743639796577 # "5dpuPtPa9ot69yew" + 3b6b65792d69643d6261667972656963 # ";key-id=bafyreic" + 756274783577716f336e6f7363346361 # "ubtx5wqo3nosc4ca" + 7a726b63746668776436726577657a67 # "zrkctfhwd6rewezg" + 70776f6534737769726c733465626468 # "pwoe4swirls4ebdh" + 733269 # "s2i" ++ +
When consuming DID Documents that are represented as CBOR, in addition to the suggestions in section 3.9 of the CBOR [[RFC7049]] specification for deterministic mappings the following constraints of the DID Document model MUST be followed:
+In CBOR, one point of extensibility is with the use of CBOR tags. [[RFC7049]] defines a basic set of data types, as + well as a tagging mechanism that enables extending the set of data types supported via an IANA registry [[CBOR-TAG-Registry]]. This allows for tags to enhance the semantic description of the data that follows. +
+ +DagCBOR is a further restricted subset of CBOR for representing the DID Document as a Directed Acyclic Graph model using canonical CBOR encoding as noted above with additional constraits. DagCBOR requires that there exist a single way of encoding any given object, and that encoded forms contain no superfluous data that may be ignored or lost in a round-trip decode/encode. When producing and consuming DID Documents representing in DagCBOR the following rules MUST be followed
+ +{ "@context": "https://www.w3.org/ns/did/v1",
+ "authentication": [
+ "did:example:12D3KooWMHdrzcwpjbdrZs5GGqERAvcgqX3b5dpuPtPa9ot69yew;key-id=bafyreicubtx5wqo3nosc4cazrkctfhwd6rewezgpwoe4swirls4ebdhs2i"
+ ],
+ "created": "2018-12-01T03:00:00Z",
+ "id": "did:example:12D3KooWMHdrzcwpjbdrZs5GGqERAvcgqX3b5dpuPtPa9ot69yew",
+ "proof": {
+ "created": "2020-05-01T03:00:02Z",
+ "creator": "did:example:12D3KooWMHdrzcwpjbdrZs5GGqERAvcgqX3b5dpuPtPa9ot69yew; example:key=id=bafyreicubtx5wqo3nosc4cazrkctfhwd6rewezgpwoe4swirls4ebdhs2i",
+ "signatureValue": "o9r6LxgoGN8FoaeeUA6EdDcv12GvDzFEmCgjWzvpur2YSQyA8W2r0SSWUK+nH5tMqzaFLun6wwZ1Eot37amGDg==",
+ "type": "ed25519Signature2018"
+ },
+ "publicKey": [
+ {
+ "curve": "ed25519",
+ "expires": "2019-12-01T03:00:00Z",
+ "id": "bafyreicubtx5wqo3nosc4cazrkctfhwd6rewezgpwoe4swirls4ebdhs2i;example:key=idbafyreicubtx5wqo3nosc4cazrkctfhwd6rewezgpwoe4swirls4ebdhs2i",
+ "publicKeyBase64": "qmz7tpLNKKKdl7cD7PbejDiBVp7ONpmZbfmc7cEK9mg=",
+ "type": "EdDsaPublicKey"
+ }
+ ],
+ "updated": "2020-05-01T03:00:00Z"
+}
+
+A DID Document proof may be constructed using CBOR semantic tagging, such as tag 98 for CBOR Object Signing and Encryption (COSE) [[RFC8152]]
+ ++ D8 62 # tag(98) + 67 # text(7) + 7061796c6f6164 # "payload" + d8 2a # tag(42) + 58 25 # bytes(37) + 00017112206c8fdc5c3d2302dda95034 # "\x00\x01q\x12 l\x8f\xdc\\=#\x02\xdd\xa9P4" + f9de57a8591918ecb7d7789387c547f7 # "\xf9\xdeW\xa8Y\x19\x18\xec\xb7\xd7x\x93\x87\xc5G\xf7" + a89d05e72f # "\xa8\x9d\x05\xe7/" + 69 # text(9) + 70726f746563746564 # "protected" + a0 # map(0) + 6a # text(10) + 7369676e617475726573 # "signatures" + 81 # array(1) + a3 # map(3) + 69 # text(9) + 70726f746563746564 # "protected" + 66 # text(6) + 613130313236 # "a10126" + 69 # text(9) + 7369676e6174757265 # "signature" + 78 80 # text(128) + 65326165616664343064363964313964 # "e2aeafd40d69d19d" + 66653665353230373763356437666634 # "fe6e52077c5d7ff4" + 65343038323832636265666235643036 # "e408282cbefb5d06" + 63626634313461663265313964393832 # "cbf414af2e19d982" + 61633435616339386238353434633930 # "ac45ac98b8544c90" + 38623435303764653165393062373137 # "8b4507de1e90b717" + 63336433343831366665393236613262 # "c3d34816fe926a2b" + 39386635336166643266613066333061 # "98f53afd2fa0f30a" + 6b # text(11) + 756e70726f746563746564 # "unprotected" + a1 # map(1) + 63 # text(3) + 6b6964 # "kid" + 78 85 # text(133) + 6469643a697069643a313244334b6f6f # "did:ipid:12D3Koo" + 574d4864727a6377706a6264725a7335 # "WMHdrzcwpjbdrZs5" + 47477145524176636771583362356470 # "GGqERAvcgqX3b5dp" + 7550745061396f7436397965773b6970 # "uPtPa9ot69yew;ip" + 69643a6b65792d69643d626166797265 # "id:key-id=bafyre" + 6963756274783577716f336e6f736334 # "icubtx5wqo3nosc4" + 63617a726b6374666877643672657765 # "cazrkctfhwd6rewe" + 7a6770776f6534737769726c73346562 # "zgpwoe4swirls4eb" + 6468733269 # "dhs2i" + 6b # text(11) + 756e70726f746563746564 # "unprotected" + a0 # tag(0) ++ +
+Fragment identifiers used with +application/did+cbor are treated +according to the rules defined in +DID Core v1.0, Fragment [[DID-CORE]]. +
++Fragment identifiers used with +application/did+cbor are treated +according to the rules defined in +DID Core v1.0, Fragment [[DID-CORE]]. +
+