JSON Object Signing and Encryption (JOSE) S. Erdtman Internet-Draft Spotify AB Intended status: Informational A. Rundgren Expires: March 10, 2019 Independent M. Jones Microsoft September 6, 2018 Cleartext JSON Web Signature (JWS) draft-erdtman-jose-cleartext-jws-01 Abstract Cleartext JSON Web Signature (JWS) is a means of signing JSON objects directly without representing the JSON to be signed in a non-JSON representation, such as base64url-encoded JSON. The signature and information about the signature is added to the JSON object when it is signed. The signature calculation for signing the JSON object uses the JSON canonicalization defined by [I-D.rundgren-json-canonicalization-scheme]. Cleartext JWS builds on the JWS, JWA, and JWK specifications, reusing data structures and semantics from these specifications, where applicable. Status of This Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at https://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." This Internet-Draft will expire on March 10, 2019. Copyright Notice Copyright (c) 2018 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents Erdtman, et al. Expires March 10, 2019 [Page 1] Internet-Draft draft-erdtman-jose-cleartext-jws September 2018 (https://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4 3. The Signature Object . . . . . . . . . . . . . . . . . . . . 4 3.1. Signature Scope . . . . . . . . . . . . . . . . . . . . . 4 3.2. The "signature" Header Parameter . . . . . . . . . . . . 5 3.3. The "signers" Header Parameter . . . . . . . . . . . . . 5 4. Producing and Consuming Cleartext JWSs . . . . . . . . . . . 5 4.1. Message Signature or MAC Computation . . . . . . . . . . 5 4.2. Message Signature or MAC Validation . . . . . . . . . . . 6 4.3. Multiple Signatures . . . . . . . . . . . . . . . . . . . 7 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 8 5.1. JSON Header Parameters Registry . . . . . . . . . . . . . 8 5.1.1. Registry Contents . . . . . . . . . . . . . . . . . . 8 6. Security Considerations . . . . . . . . . . . . . . . . . . . 9 7. References . . . . . . . . . . . . . . . . . . . . . . . . . 9 7.1. Normative References . . . . . . . . . . . . . . . . . . 9 7.2. Informative References . . . . . . . . . . . . . . . . . 10 Appendix A. Test Vectors . . . . . . . . . . . . . . . . . . . . 10 A.1. Multiple Signatures with Top-Level "alg" Header Parameter 10 A.2. Multiple Signatures with Top-Level "crit" Header Parameter . . . . . . . . . . . . . . . . . . . . . . . . 11 A.3. Elliptic Curve Key "example.com:p256" . . . . . . . . . . 11 A.4. Elliptic Curve Key "example.com:p256-2" . . . . . . . . . 12 A.5. RSA Key "example.com:r2048" . . . . . . . . . . . . . . . 12 Appendix B. Acknowledgements . . . . . . . . . . . . . . . . . . 13 Appendix C. Open Issues . . . . . . . . . . . . . . . . . . . . 13 Appendix D. Document History . . . . . . . . . . . . . . . . . . 14 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 14 1. Introduction Cleartext JSON Web Signature (JWS) represents a signed JSON object directly as a JSON object [RFC8259], without representing the JSON to be signed in a non-JSON representation, such as base64url-encoded JSON. The signature and information about the signature is added to the JSON object when it is signed. The signature calculation for signing the JSON object uses the JSON canonicalization defined by [I-D.rundgren-json-canonicalization-scheme]. By including the Erdtman, et al. Expires March 10, 2019 [Page 2] Internet-Draft draft-erdtman-jose-cleartext-jws September 2018 signature information in the JSON object to be signed, it is easy to inspect data in transit and when archived, integrity can be guaranteed. Cleartext JWS builds on the JWS [RFC7515], JWA [RFC7518], and JWK [RFC7517] specifications, reusing data structures and semantics from these specifications, where applicable. Cryptographic algorithm identifiers used by this specification come from the IANA "JSON Web Signature and Encryption Algorithms" registry [IANA.JOSE.Algorithms]. There are three essential differences between Cleartext JWS and JWS: o Cleartext JWS can only sign JSON objects, rather than arbitrary data. o Cleartext JWS signature information is included within the signed data. o Cleartext JWS depends on predictable JSON Serialization, rather than base64url-encoding the data to be signed. The table below is a comparison of JWS and Cleartext JWS: +-------------------------------+----------------+------------------+ | | JWS | Cleartext JWS | +-------------------------------+----------------+------------------+ | Data to be Signed | Arbitrary data | JSON or | | | | JavaScript | | | | objects | | Encoding of Signed Data | Base64url | None | | Encoding of Header Parameters | Base64url | None | | URL Friendly | Core feature | Out of scope | +-------------------------------+----------------+------------------+ In the following example, note that the signature information is included in the JSON object. The members in the "__cleartext_signature" object are the JWS Header Parameters for the signature. The "signature" member contains the base64url-encoded signature value. (Line breaks within values are for display purposes only.) Erdtman, et al. Expires March 10, 2019 [Page 3] Internet-Draft draft-erdtman-jose-cleartext-jws September 2018 { "iss": "joe", "exp": 1300819380, "escapeMe": "\u20ac$\u000F\u000aA'\u0042\u0022\u005c\\\"\/", "numbers": [1e+30,4.5,6], "__cleartext_signature": { "alg": "ES256", "kid": "example.com:p256", "signature": "pXP0GFHms0SntctNk1G1pHZfccVYdZkmAJktY_hpMsI AckzX7wZJIJNlsBzmJ1_7LmKATiW-YHHZjsYdT96JZw" } } The key in Appendix A.3 can be used for verifying the example signature. Note: Recreating the example signature using the example private key would normally result in a different "signature" value since ECDSA includes random data in the signature calculation. 2. Terminology 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. 3. The Signature Object When signing JSON data with Cleartext JWS, a JSON object with the JWS Header Parameters is created and placed within the JSON data to be signed. In addition to the already defined JWS Header Parameters, Cleartext JWS defines two new Header Parameters: "signature" for the base64url-encoded signature value and "signers" to support multiple signers within the same signature object. The identifier for the Cleartext Signature Object in the JSON data to be signed MUST be "__cleartext_signature", unless the application specifies that a different identifier is to be used. 3.1. Signature Scope The scope of a signature (the data that is actually signed) comprises all values including child objects of the signature object except for the "signature" member. If multiple signers are present, only the data pertaining to all signers and the data specific to that signer Erdtman, et al. Expires March 10, 2019 [Page 4] Internet-Draft draft-erdtman-jose-cleartext-jws September 2018 are included (but not the data specific to other signers). See Section 4.3 for more about the multiple signatures case. 3.2. The "signature" Header Parameter The "signature" Header Parameter contains the base64url-encoded JWS Signature as a string. 3.3. The "signers" Header Parameter The optional "signers" Header Parameter contains an array of sets of Header Parameters that are specific to each signer, including the "signature" value for each signer. See Section 4.3 for more about the multiple signatures case. 4. Producing and Consuming Cleartext JWSs 4.1. Message Signature or MAC Computation To create a Cleartext JWS, the following steps are performed. The order of the steps is not significant in cases where there are no dependencies between the inputs and outputs of the steps. 1. Create the application specific JSON object to be signed. In this step the JSON should not be canonicalized. 2. Create the "__cleartext_signature" object with the Header Parameters to be used and add it as a top-level member to the JSON object to be signed with the key "__cleartext_signature". 3. Canonicalize the JOSN object to be signed using the canocalization process defined by [I-D.rundgren-json-canonicalization-scheme]. Let the output of the canonicalization be the cleartext input to the signature algorithm. 4. Compute the JWS Signature in the manner defined for the particular algorithm being used over the canonicalize JSON object to be signed. The "alg" (algorithm) Header Parameter MUST be present in the "__cleartext_signature" member, with the algorithm value accurately representing the algorithm used to construct the JWS Signature. 5. Add the "signature" member to the signature object (__cleartext_signature) within the original application JSON object. with the value BASE64URL(JWS Signature). Erdtman, et al. Expires March 10, 2019 [Page 5] Internet-Draft draft-erdtman-jose-cleartext-jws September 2018 4.2. Message Signature or MAC Validation When validating a Cleartext JWS, the following steps are performed. The order of the steps is not significant in cases where there are no dependencies between the inputs and outputs of the steps. If any of the listed steps fails, then the input MUST be rejected. When there are multiple JWS Signature values, it is an application decision which of the JWS Signature values must successfully validate for the Cleartext JWS to be accepted. In some cases, all must successfully validate, or the Cleartext JWS will be considered invalid. In other cases, only a specific JWS Signature value needs to be successfully validated. However, in all cases, at least one JWS Signature value MUST successfully validate, or the Cleartext JWS MUST be considered invalid. 1. Parse the application JSON data, including the signature object. 2. Verify that the implementation understands and can process all fields that it is required to support, whether required by this specification, by the algorithm being used, or by the "crit" Header Parameter value, and that the values of those parameters are also understood and supported. 3. Save and remove the "signature" member from the signature object (__cleartext_signature) and base64url-decode the encoded representation of the JWS Signature. 4. Canonicalize the signed object, including the signature object (__cleartext_signature), by following the rules by [I-D.rundgren-json-canonicalization-scheme] and let the output be input to the signature algorithm. 5. Validate the JWS Signature against the JWS Signing Input, i.e., the canonicalize data, in the manner defined for the algorithm being used, which MUST be accurately represented by the value of the "alg" (algorithm) Header Parameter value, which MUST be present. Record whether the validation succeeded or not. 6. Return a result indicating whether or not the Cleartext JWS was successfully validated. 7. For later validation of the signed JSON object, put the "signature" member back into the signature object (__cleartext_signature) within the application JSON object. Erdtman, et al. Expires March 10, 2019 [Page 6] Internet-Draft draft-erdtman-jose-cleartext-jws September 2018 4.3. Multiple Signatures Multiple signers using different keys can independently add signatures to a JSON object in the manner described in this section. The signature procedure is essentially the same as for single signatures but also includes the following: o There MUST be an additional JWS Header parameter "signers", holding an array of signature objects. o Each signature requires its own canocalization process. During this process, the signature objects for other signatures MUST be (temporarily) removed. o The canonicalized data in the "signers" value MUST include the array brackets ([]) containing the data specific to this signature but MUST NOT include the data for other signatures. The resulting array will be single-valued, with no commas separating additional elements. o A given Header Parameter MUST NOT occur in both the top-level signature object and a signature object within the "signers" value. Any Header Parameter occurring in the top-level signature object applies to all signatures. o A signature object is equivalent to an ordinary signature object, but MAY exclude the "alg" Header parameter if it is present in the top-level signature object itself. If in the top-level signature object, all enclosed signature objects MUST use the same algorithm as well as not including the "alg" Header parameter. See Appendix A.1 for an example. o Likewise, if a "crit" Header parameter is specified in the top- level signature object, it MUST be applied to all signature objects and MUST NOT be present in them individually. See Appendix A.2 for an example. The following example shows a multiply signed object: Erdtman, et al. Expires March 10, 2019 [Page 7] Internet-Draft draft-erdtman-jose-cleartext-jws September 2018 { "iss": "joe", "exp": 1300819380, "escapeMe": "\u20ac$\u000F\u000aA'\u0042\u0022\u005c\\\"\/", "numbers": [1e+30,4.5,6], "__cleartext_signature": { "signers": [{ "alg": "ES256", "kid": "example.com:p256", "signature": "83gr5rmjKgngLTaPpxuQWiZaQmlQ555jLHNcZLmcBpg X7JZLeqrNhIrQRg3jTsNwh1RuibDYBzCsaxVUkhGEKg" },{ "alg": "RS256", "kid": "example.com:r2048", "signature": "PVQeL8XtjnetambQe98FuMBDuijwWTIFXouyNjL8WX0 WvamWkHjv34Iz8VOHHWr9w8t14FXJJuQ22j-h5BR7qP xE7cBVS8XSltR7VvcNidfn-r-TtAVwDwn7Iz_Gk-RI7 QIv4ctbreYt1myG64Ikw38OEmNURCxzf9h9w3tvA3R8 ZE3MYgELFaQRowSW92JC1HhGZRijzHoIzvH6l_GULP_ hf7kggwFNtRrzN8DLXbhBhGaoP-O0cNZsCWY2hbNU6L 7km6bdrqHdq88DSOEGg_-5T6qUsIAYbmCgUK7XBi2q- DRPQZYnxr5570mj9Nkh0hpZ-VfAC2ftbzxFAB7ZYg" }] } } The ECDSA signature can be validated using the key in Appendix A.3 and the RSA signature can be validated using the key in Appendix A.5. 5. IANA Considerations 5.1. JSON Header Parameters Registry This section registers the following Header Parameters in the IANA "JSON Web Signature and Encryption Header Parameters" registry [IANA.JOSE.HeaderParameters]. 5.1.1. Registry Contents o Header Parameter Name: "signature" o Header Parameter Description: The base64url-encoded signature value o Header Parameter Usage Location(s): "Cleartext JWS" o Change Controller: IESG Erdtman, et al. Expires March 10, 2019 [Page 8] Internet-Draft draft-erdtman-jose-cleartext-jws September 2018 o Specification Document(s): Section 3.2 o Header Parameter Name: "signers" o Header Parameter Description: List of signature objects, each with a set of Header Parameters and a signature value o Header Parameter Usage Location(s): "Cleartext JWS" o Change Controller: IESG o Specification Document(s): Section 3.3 6. Security Considerations The same security considerations apply to this specification as do for JWS [RFC7515]. 7. References 7.1. Normative References [I-D.rundgren-json-canonicalization-scheme] Rundgren, A., "JSON Canonicalization Scheme (JCS)", draft- rundgren-json-canonicalization-scheme-01 (work in progress), June 2018. [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, . [RFC7515] Jones, M., Bradley, J., and N. Sakimura, "JSON Web Signature (JWS)", RFC 7515, DOI 10.17487/RFC7515, May 2015, . [RFC7517] Jones, M., "JSON Web Key (JWK)", RFC 7517, DOI 10.17487/RFC7517, May 2015, . [RFC7518] Jones, M., "JSON Web Algorithms (JWA)", RFC 7518, DOI 10.17487/RFC7518, May 2015, . [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, May 2017, . Erdtman, et al. Expires March 10, 2019 [Page 9] Internet-Draft draft-erdtman-jose-cleartext-jws September 2018 [RFC8259] Bray, T., Ed., "The JavaScript Object Notation (JSON) Data Interchange Format", STD 90, RFC 8259, DOI 10.17487/RFC8259, December 2017, . 7.2. Informative References [IANA.JOSE.Algorithms] IANA, "JSON Web Signature and Encryption Algorithms", . [IANA.JOSE.HeaderParameters] IANA, "JSON Web Signature and Encryption Header Parameters", . Appendix A. Test Vectors This section contains a set of test vectors. (Line breaks within values are for display purposes only.) A.1. Multiple Signatures with Top-Level "alg" Header Parameter { "iss": "joe", "exp": 1300819380, "escapeMe": "\u20ac$\u000F\u000aA'\u0042\u0022\u005c\\\"\/", "numbers": [1e+30,4.5,6], "__cleartext_signature": { "alg": "ES256", "signers": [{ "kid": "example.com:p256", "signature": "En1Iyg45g1HBsxYdu-SR1fjt2nixOEtMWRrVA9EO7N8QfZtrs cEfNl0tkIthqKWXGGPNmWKSw9Bc0Cj6kjHMKA" },{ "kid": "example.com:p256-2", "signature": "RVNSVosrweujm36TDq9661oZiORdPMe-A-v-TADFO_mm6ss96 QnVP_BqT9kIc7nSlW7lOeMWk5Tq4kL4d3M_Mw" }] } } } The first signature can be verified using the key in Appendix A.3 and the second signature can be verified using the key in Appendix A.4. Erdtman, et al. Expires March 10, 2019 [Page 10] Internet-Draft draft-erdtman-jose-cleartext-jws September 2018 A.2. Multiple Signatures with Top-Level "crit" Header Parameter { "iss": "joe", "exp": 1300819380, "escapeMe": "\u20ac$\u000F\u000aA'\u0042\u0022\u005c\\\"\/", "numbers": [1e+30,4.5,6], "__cleartext_signature": { "crit": ["otherExt","https://example.com/extension"], "signers": [{ "alg": "ES256", "kid": "example.com:p256", "otherExt": "Other Data", "signature": "S9PqQU5z5zThIGUvErzf7oo8EetiUFEI1v8flisWJzw0HqqY- OuT_pDq1rG4gsSRAFjrazurl4NGyyxcPfeXzw" },{ "alg": "RS256", "kid": "example.com:r2048", "otherExt": "Cool Stuff", "https://example.com/extension": { "life-is-great": true }, "signature": "O-cnYTtgvyGmgX1YMQkcnRE0lnBw1EduMNVpdblKP-Iy0S143 BBvXrCQoEW9oTkQm7X9wkJoohWQyU4qvojoxQxmf6GQ0tEXEI HqN7ixkPh_3ySXTl-gKTPiA5UL-GV44AS-k6N71qp8XhLORmU m68UlTWBZaOXL0JTGjsCyGpuwNiAQbx39ZbjabvGq4NfpPIQC 2yjx_SKoPMiia54Mp0hz8U_S3oyAmHrG2mKFYrJ7k43aeDHK1 RNRu8XrW2w-Ffh4KigpClAq4q272ZSsjizfYPPjW3gqInjMZz Qd8yZj5Bi5vCDcBOEKZMDoog-UzIy8SbZNl85TlkhK70oNRQ" }] } } The first signature can be verified using the key in Appendix A.3 and the second signature can be verified using the key in Appendix A.5. A.3. Elliptic Curve Key "example.com:p256" Elliptic Curve private key, represented as a JWK: { "kid": "example.com:p256", "kty": "EC", "crv": "P-256", "x": "censDzcMEkgiePz6DXB7cDuwFemshAFR90UNVQFCg8Q", "y": "xq8rze6ewG0-eVcSF72J77gKiD0IHnzpwHaU7t6nVeY", "d": "nEsftLbi5u9pI8B0-drEjIuJzQgZie3yeqUR3BwWDl4" } Erdtman, et al. Expires March 10, 2019 [Page 11] Internet-Draft draft-erdtman-jose-cleartext-jws September 2018 A.4. Elliptic Curve Key "example.com:p256-2" Elliptic Curve private key, represented as a JWK: { "kid": "example.com:p256-2", "kty": "EC", "crv": "P-256", "x": "RgdKcWxBsnqeryzoEv3B5KE9qAQc-nBZEV_A23uQoPs", "y": "73UtZIe1Qfil1WM9Hq1ZiPXWnI1Tu7N__goVvTyjURk", "d": "2jlPu5M9ISDkk-cpPgj6XGvZMhrFUfPujtQy2LtMOss" } A.5. RSA Key "example.com:r2048" RSA private key, represented as a JWK: Erdtman, et al. Expires March 10, 2019 [Page 12] Internet-Draft draft-erdtman-jose-cleartext-jws September 2018 { "kid": "example.com:r2048", "kty": "RSA", "n": "hFWEXArvaZEpSP5qNX7x4C4Hl28GJQTNvnDwkfqiWs63kXbdyPeS06bz6GnY3 tfQ_093nGauWsimqKBmGAGMPtsV83Qxw1OIeO4ujbIIb9pema0qtVqs0MWlHx klZGFkYfAmbuEUFxYDeLDHe0bkkXbSlB7_t8pCSvc8HLgHjEQjYOlFRwjR0D- uLo-xgsCbpmCtYkB5lcT_zFgpRgY4zJNLSv7GZiz2S4Fc5ArGjd34lL47-L8b ozuYjqNOv9sqX0Zgll5XaJ1ndvr7UqZu1xQFgm38reoM3IarBP_SkEFbt_v9i ak602VO3k28fQhMaocP7JWR2YLT3kZM0-WTFw", "e": "AQAB", "d": "Q6iBYpnIrB2mkQZagP1lZuvBv9_osVaSZpLRvKD7DxhvbDTs0coaTJIoVCSB1 _VZip8zlUg-TnYWF1Liv9VSwfQ7ddxrcOUtej60mId0ntNz2HhbxJsWjiru8E ZoArl0nEovLDNxlRgRMEyZwOKPC_xHT6nFrk7_s9pR5pEEcubGLAVBKnLCoPd Lr-CBjCvWfJo73W5AZxoSb8MdWQOi5viXHURpr1Y_uBRsMuclovM56Vt05etM sB1AbcTLUDwAuYrZWa1c08ql60ft7b3v6Q_rCL7EHtFU3PHAuP0mV7tM5BfAP f4T0g9pbr4GOw7eqQCiYgPFE7gmCR_PDxv5YQ", "p": "6DIM343hAtj1hQprJaVQ3T8YeIytIQ7Ma544C0A8BX-irjJfARy4fAlTSyBFe auZ0WdbMGtKpAIgNVmfCfuP7W1bXw7UaxpqsQlbw54K1VtBs8xG-lee_2YQ3l UlIiC1at6L0jxWYNkvp-LIfU2F5ZQir5ZWVXwgdMcgoNBABMc", "q": "keacq0goV7pAtG2h33OAk-XOSclIF1agvEMMOKuud5V-vGQ6OaYldlYqZmSGg F7RVlX0GZO70nPqatjd2G-tI8wEq5K_xmLQurUPFW8g___z0CTgJ62KbjFxCt Gny5rsObX9im6cCc_EOtWZRaApzO8ykxfo1QcEjT4k1na7DzE", "dp": "nPmJPnFal2Q5x_GdMlwq6QhI8OaZ_OlWRcM3PFP2v_jj8ERZehUCm8hqKTXu Ai2C1dC8E2XVlj9hqu-l10fcq7Tsurz52laHnpwnD35-8HK7XmRR79jgwuUr rkN90S6vt0ow2La15s-tqiBlTmDkjqqxMGfAghZiktA0PMPNI-0", "dq": "D3c1lkZw2FPK9hVE-m3A7GyIwHOQq8CoCyzER-GS_eQf6hJpxaCiCfg6SF5R j5v9brxvwqJRX46gA7F3WrED1m6S9Cj7ISlqXNBCiBAenGRiUOcHx8zyhpnB FNeChOeoMLnk5V6yNawLbf0kYSgIJkwYvVTkfmhfCCXVO9KcI5E", "qi": "wV0NzfCakfog1NFjtPzcga1MtkpizgPkxcP9LjNdvXW2YQZhM6GIEGjsu3iv TrHrrM-4_bTQHOoTtfIY7wdqBKlwQTJOI0dH9FbNJ4ecGojRwgv83TN8aNKh 17Tt44jI5oibs2P-31B_VW9R1wwhnnOuCYpABfoSbtHIoCRme5I" } Appendix B. Acknowledgements This document builds on the work done in the JOSE working group, so a big thanks goes out to all involved in that work. It is specifically inspired by JWS, so special thanks are due to the authors of that document, Michael B. Jones, John Bradley, and Nat Sakimura. Appendix C. Open Issues The following open issues remain to be addressed in this specification. o The signature creation and validation steps for the multiple signatures case needs to be added to Section 4.1 and Section 4.2. Erdtman, et al. Expires March 10, 2019 [Page 13] Internet-Draft draft-erdtman-jose-cleartext-jws September 2018 Appendix D. Document History [[ to be removed by the RFC Editor before publication as an RFC ]] -01 o Changed canocalization from ES6 serialization to [I-D.rundgren-json-canonicalization-scheme]. o "signature object" is now used consistently through out the specification. -00 o Initial version. Authors' Addresses Samuel Erdtman Spotify AB Birger Jarlsgatan 61, 4tr Stockholm 113 56 Sweden Email: erdtman@spotify.com Anders Rundgren Independent Montpellier France Email: anders.rundgren.net@gmail.com Michael B. Jones Microsoft Email: mbj@microsoft.com URI: http://self-issued.info/ Erdtman, et al. Expires March 10, 2019 [Page 14]