JOSE Working Group                                              M. Jones
Internet-Draft                                                 Microsoft
Intended status: Standards Track                            May 28, 2013
Expires: November 29, 2013


                           JSON Web Key (JWK)
                    draft-ietf-jose-json-web-key-11

Abstract

   A JSON Web Key (JWK) is a JavaScript Object Notation (JSON) data
   structure that represents a cryptographic key.  This specification
   also defines a JSON Web Key Set (JWK Set) JSON data structure for
   representing a set of JWKs.  Cryptographic algorithms and identifiers
   for use with this specification are described in the separate JSON
   Web Algorithms (JWA) specification.

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 http://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 November 29, 2013.

Copyright Notice

   Copyright (c) 2013 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
   (http://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



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   described in the Simplified BSD License.


Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  3
     1.1.  Notational Conventions . . . . . . . . . . . . . . . . . .  3
   2.  Terminology  . . . . . . . . . . . . . . . . . . . . . . . . .  3
   3.  JSON Web Key (JWK) Format  . . . . . . . . . . . . . . . . . .  4
     3.1.  "kty" (Key Type) Parameter . . . . . . . . . . . . . . . .  4
     3.2.  "use" (Key Use) Parameter  . . . . . . . . . . . . . . . .  5
     3.3.  "alg" (Algorithm) Parameter  . . . . . . . . . . . . . . .  5
     3.4.  "kid" (Key ID) Parameter . . . . . . . . . . . . . . . . .  5
     3.5.  "x5u" (X.509 URL) Header Parameter . . . . . . . . . . . .  5
     3.6.  "x5t" (X.509 Certificate Thumbprint) Header Parameter  . .  6
     3.7.  "x5c" (X.509 Certificate Chain) Parameter  . . . . . . . .  6
   4.  JSON Web Key Set (JWK Set) Format  . . . . . . . . . . . . . .  6
     4.1.  "keys" (JSON Web Key Set) Parameter  . . . . . . . . . . .  6
   5.  String Comparison Rules  . . . . . . . . . . . . . . . . . . .  6
   6.  Encrypted JWK and Encrypted JWK Set Formats  . . . . . . . . .  7
   7.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . .  7
     7.1.  JSON Web Key Parameters Registry . . . . . . . . . . . . .  8
       7.1.1.  Registration Template  . . . . . . . . . . . . . . . .  8
       7.1.2.  Initial Registry Contents  . . . . . . . . . . . . . .  8
     7.2.  JSON Web Key Set Parameters Registry . . . . . . . . . . .  9
       7.2.1.  Registration Template  . . . . . . . . . . . . . . . .  9
       7.2.2.  Initial Registry Contents  . . . . . . . . . . . . . . 10
     7.3.  JSON Web Signature and Encryption Type Values
           Registration . . . . . . . . . . . . . . . . . . . . . . . 10
       7.3.1.  Registry Contents  . . . . . . . . . . . . . . . . . . 10
     7.4.  Media Type Registration  . . . . . . . . . . . . . . . . . 10
       7.4.1.  Registry Contents  . . . . . . . . . . . . . . . . . . 10
   8.  Security Considerations  . . . . . . . . . . . . . . . . . . . 11
   9.  References . . . . . . . . . . . . . . . . . . . . . . . . . . 12
     9.1.  Normative References . . . . . . . . . . . . . . . . . . . 12
     9.2.  Informative References . . . . . . . . . . . . . . . . . . 13
   Appendix A.  Example JSON Web Key Sets . . . . . . . . . . . . . . 14
     A.1.  Example Public Keys  . . . . . . . . . . . . . . . . . . . 14
     A.2.  Example Private Keys . . . . . . . . . . . . . . . . . . . 15
     A.3.  Example Symmetric Keys . . . . . . . . . . . . . . . . . . 17
   Appendix B.  Example Use of "x5c" (X.509 Certificate Chain)
                Parameter . . . . . . . . . . . . . . . . . . . . . . 17
   Appendix C.  Acknowledgements  . . . . . . . . . . . . . . . . . . 18
   Appendix D.  Document History  . . . . . . . . . . . . . . . . . . 19
   Author's Address . . . . . . . . . . . . . . . . . . . . . . . . . 22






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1.  Introduction

   A JSON Web Key (JWK) is a JavaScript Object Notation (JSON) [RFC4627]
   data structure that represents a cryptographic key.  This
   specification also defines a JSON Web Key Set (JWK Set) JSON data
   structure for representing a set of JWKs.  Cryptographic algorithms
   and identifiers for use with this specification are described in the
   separate JSON Web Algorithms (JWA) [JWA] specification.

   Goals for this specification do not include representing certificate
   chains, representing certified keys, and replacing X.509
   certificates.

   JWKs and JWK Sets are used in the JSON Web Signature (JWS) [JWS] and
   JSON Web Encryption (JWE) [JWE] specifications.

1.1.  Notational Conventions

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in Key words for use in
   RFCs to Indicate Requirement Levels [RFC2119].


2.  Terminology

   JSON Web Key (JWK)  A JSON object that represents a cryptographic
      key.

   JSON Web Key Set (JWK Set)  A JSON object that contains an array of
      JWKs as the value of its "keys" member.

   Base64url Encoding  The URL- and filename-safe Base64 encoding
      described in RFC 4648 [RFC4648], Section 5, with the (non URL-
      safe) '=' padding characters omitted, as permitted by Section 3.2.
      (See Appendix C of [JWS] for notes on implementing base64url
      encoding without padding.)

   Collision Resistant Namespace  A namespace that allows names to be
      allocated in a manner such that they are highly unlikely to
      collide with other names.  For instance, collision resistance can
      be achieved through administrative delegation of portions of the
      namespace or through use of collision-resistant name allocation
      functions.  Examples of Collision Resistant Namespaces include:
      Domain Names, Object Identifiers (OIDs) as defined in the ITU-T
      X.660 and X.670 Recommendation series, and Universally Unique
      IDentifiers (UUIDs) [RFC4122].  When using an administratively
      delegated namespace, the definer of a name needs to take



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      reasonable precautions to ensure they are in control of the
      portion of the namespace they use to define the name.

   Encrypted JWK  A JWE with a JWK as its plaintext value.

   Encrypted JWK Set  A JWE with a JWK Set as its plaintext value.


3.  JSON Web Key (JWK) Format

   A JSON Web Key (JWK) is a JSON object containing specific members, as
   specified below.  Those members that are common to all key types are
   defined below.

   In addition to the common parameters, each JWK will have members that
   are specific to the kind of key being represented.  These members
   represent the parameters of the key.  Section 5 of the JSON Web
   Algorithms (JWA) [JWA] specification defines multiple kinds of
   cryptographic keys and their associated members.

   The member names within a JWK MUST be unique; objects with duplicate
   member names MUST be rejected.

   Additional members MAY be present in the JWK.  If not understood by
   implementations encountering them, they MUST be ignored.  Member
   names used for representing key parameters for different kinds of
   keys need not be distinct.  Any new member name SHOULD either be
   registered in the IANA JSON Web Key Parameters registry Section 7.1
   or be a value that contains a Collision Resistant Namespace.

3.1.  "kty" (Key Type) Parameter

   The "kty" (key type) member identifies the cryptographic algorithm
   family used with the key. "kty" values SHOULD either be registered in
   the IANA JSON Web Key Types registry [JWA] or be a value that
   contains a Collision Resistant Namespace.  The "kty" value is a case
   sensitive string.  Use of this member is REQUIRED.

   A list of defined "kty" values can be found in the IANA JSON Web Key
   Types registry [JWA]; the initial contents of this registry are the
   values defined in Section 5.1 of the JSON Web Algorithms (JWA) [JWA]
   specification.

   Additional members used with these "kty" values can be found in the
   IANA JSON Web Key Parameters registry Section 7.1; the initial
   contents of this registry are the values defined in Sections 5.2 and
   5.3 of the JSON Web Algorithms (JWA) [JWA] specification.




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3.2.  "use" (Key Use) Parameter

   The "use" (key use) member identifies the intended use of the key.
   Values defined by this specification are:

   o  "sig" (signature or MAC operation)

   o  "enc" (encryption)

   Other values MAY be used.  The "use" value is a case sensitive
   string.  Use of this member is OPTIONAL.

3.3.  "alg" (Algorithm) Parameter

   The "alg" (algorithm) member identifies the algorithm intended for
   use with the key.  The values used in this field are the same as
   those used in the JWS [JWS] and JWE [JWE] "alg" and "enc" header
   parameters; these values can be found in the JSON Web Signature and
   Encryption Algorithms registry [JWA].  Use of this member is
   OPTIONAL.

3.4.  "kid" (Key ID) Parameter

   The "kid" (key ID) member can be used to match a specific key.  This
   can be used, for instance, to choose among a set of keys within a JWK
   Set during key rollover.  The interpretation of the "kid" value is
   unspecified.  When "kid" values are used within a JWK Set, different
   keys within the JWK Set SHOULD use distinct "kid" values.  The "kid"
   value is a case sensitive string.  Use of this member is OPTIONAL.

   When used with JWS or JWE, the "kid" value can be used to match a JWS
   or JWE "kid" header parameter value.

3.5.  "x5u" (X.509 URL) Header Parameter

   The "x5u" (X.509 URL) member is a URI [RFC3986] that refers to a
   resource for an X.509 public key certificate or certificate chain
   [RFC5280].  The identified resource MUST provide a representation of
   the certificate or certificate chain that conforms to RFC 5280
   [RFC5280] in PEM encoded form [RFC1421].  The key in the first
   certificate MUST match the bare public key represented by other
   members of the JWK.  The protocol used to acquire the resource MUST
   provide integrity protection; an HTTP GET request to retrieve the
   certificate MUST use TLS [RFC2818] [RFC5246]; the identity of the
   server MUST be validated, as per Section 3.1 of HTTP Over TLS
   [RFC2818].  Use of this member is OPTIONAL.





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3.6.  "x5t" (X.509 Certificate Thumbprint) Header Parameter

   The "x5t" (X.509 Certificate Thumbprint) member is a base64url
   encoded SHA-1 thumbprint (a.k.a. digest) of the DER encoding of an
   X.509 certificate [RFC5280].  The key in the certificate MUST match
   the bare public key represented by other members of the JWK.  Use of
   this member is OPTIONAL.

3.7.  "x5c" (X.509 Certificate Chain) Parameter

   x5c  The "x5c" (X.509 Certificate Chain) member contains a chain of
      one or more PKIX certificates [RFC5280].  The certificate chain is
      represented as a JSON array of certificate value strings.  Each
      string in the array is a base64 encoded ([RFC4648] Section 4 --
      not base64url encoded) DER [ITU.X690.1994] PKIX certificate value.
      The PKIX certificate containing the key value MUST be the first
      certificate.  This MAY be followed by additional certificates,
      with each subsequent certificate being the one used to certify the
      previous one.  The key in the first certificate MUST match the
      bare public key represented by other members of the JWK.  Use of
      this member is OPTIONAL.


4.  JSON Web Key Set (JWK Set) Format

   A JSON Web Key Set (JWK Set) is a JSON object that contains an array
   of JSON Web Key values as the value of its "keys" member.

   The member names within a JWK Set MUST be unique; objects with
   duplicate member names MUST be rejected.

   Additional members MAY be present in the JWK Set. If not understood
   by implementations encountering them, they MUST be ignored.
   Parameters for representing additional properties of JWK Sets SHOULD
   either be registered in the IANA JSON Web Key Set Parameters registry
   Section 7.2 or be a value that contains a Collision Resistant
   Namespace.

4.1.  "keys" (JSON Web Key Set) Parameter

   The value of the "keys" (JSON Web Key Set) member is an array of JSON
   Web Key (JWK) values.  Use of this member is REQUIRED.


5.  String Comparison Rules

   Processing a JWK inevitably requires comparing known strings to
   values in JSON objects.  For example, in checking what the key type



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   is, the Unicode string encoding "kty" will be checked against the
   member names in the JWK to see if there is a matching name.

   Comparisons between JSON strings and other Unicode strings MUST be
   performed by comparing Unicode code points without normalization as
   specified in the String Comparison Rules in Section 5.3 of [JWS].


6.  Encrypted JWK and Encrypted JWK Set Formats

   JWKs containing non-public key material will need to be encrypted in
   some contexts to prevent the disclosure of private or symmetric key
   values to unintended parties.  The use of an Encrypted JWK, which is
   a JWE with a JWK as its plaintext value, is RECOMMENED for this
   purpose.  The processing of Encrypted JWKs is identical to the
   processing of other JWEs.  A "cty" (content type) header parameter
   value of "JWK" can be used to indicate that the content of the JWE is
   a JWK in contexts where this is useful.

   JWK Sets containing non-public key material will similarly need to be
   encrypted.  The use of an Encrypted JWK Set, which is a JWE with a
   JWK Set as its plaintext value, is RECOMMENED for this purpose.  The
   processing of Encrypted JWK Sets is identical to the processing of
   other JWEs.  A "cty" (content type) header parameter value of
   "JWK-SET" can be used to indicate that the content of the JWE is a
   JWK Set in contexts where this is useful.


7.  IANA Considerations

   The following registration procedure is used for all the registries
   established by this specification.

   Values are registered with a Specification Required [RFC5226] after a
   two-week review period on the [TBD]@ietf.org mailing list, on the
   advice of one or more Designated Experts.  However, to allow for the
   allocation of values prior to publication, the Designated Expert(s)
   may approve registration once they are satisfied that such a
   specification will be published.

   Registration requests must be sent to the [TBD]@ietf.org mailing list
   for review and comment, with an appropriate subject (e.g., "Request
   for access token type: example"). [[ Note to RFC-EDITOR: The name of
   the mailing list should be determined in consultation with the IESG
   and IANA.  Suggested name: jose-reg-review. ]]

   Within the review period, the Designated Expert(s) will either
   approve or deny the registration request, communicating this decision



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   to the review list and IANA.  Denials should include an explanation
   and, if applicable, suggestions as to how to make the request
   successful.

   IANA must only accept registry updates from the Designated Expert(s)
   and should direct all requests for registration to the review mailing
   list.

7.1.  JSON Web Key Parameters Registry

   This specification establishes the IANA JSON Web Key Parameters
   registry for reserved JWK parameter names.  The registry records the
   reserved parameter name and a reference to the specification that
   defines it.  It also records whether the parameter conveys public or
   private information.  This specification registers the parameter
   names defined in Section 3.  The same JWK parameter name may be
   registered multiple times, provided that duplicate parameter
   registrations are only for algorithm-specific JWK parameters; in this
   case, the meaning of the duplicate parameter name is disambiguated by
   the "kty" value of the JWK containing it.

7.1.1.  Registration Template

   Parameter Name:
      The name requested (e.g., "example").  This name is case
      sensitive.  Names that match other registered names in a case
      insensitive manner SHOULD NOT be accepted.

   Parameter Information Class:
      Registers whether the parameter conveys public or private
      information.  Its value must be one the words Public or Private.

   Change Controller:
      For Standards Track RFCs, state "IETF".  For others, give the name
      of the responsible party.  Other details (e.g., postal address,
      email address, home page URI) may also be included.

   Specification Document(s):
      Reference to the document(s) that specify the parameter,
      preferably including URI(s) that can be used to retrieve copies of
      the document(s).  An indication of the relevant sections may also
      be included but is not required.

7.1.2.  Initial Registry Contents

   o  Parameter Name: "kty"





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   o  Parameter Information Class: Public
   o  Change Controller: IETF
   o  Specification Document(s): Section 3.1 of [[ this document ]]

   o  Parameter Name: "use"
   o  Parameter Information Class: Public
   o  Change Controller: IETF
   o  Specification Document(s): Section 3.2 of [[ this document ]]

   o  Parameter Name: "alg"
   o  Parameter Information Class: Public
   o  Change Controller: IETF
   o  Specification Document(s): Section 3.3 of [[ this document ]]

   o  Parameter Name: "kid"
   o  Parameter Information Class: Public
   o  Change Controller: IETF
   o  Specification Document(s): Section 3.4 of [[ this document ]]

   o  Parameter Name: "x5u"
   o  Parameter Information Class: Public
   o  Change Controller: IETF
   o  Specification Document(s): Section 3.5 of [[ this document ]]

   o  Parameter Name: "x5t"
   o  Parameter Information Class: Public
   o  Change Controller: IETF
   o  Specification Document(s): Section 3.6 of [[ this document ]]

   o  Parameter Name: "x5c"
   o  Parameter Information Class: Public
   o  Change Controller: IETF
   o  Specification Document(s): Section 3.7 of [[ this document ]]

7.2.  JSON Web Key Set Parameters Registry

   This specification establishes the IANA JSON Web Key Set Parameters
   registry for reserved JWK Set parameter names.  The registry records
   the reserved parameter name and a reference to the specification that
   defines it.  This specification registers the parameter names defined
   in Section 4.

7.2.1.  Registration Template








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   Parameter Name:
      The name requested (e.g., "example").  This name is case
      sensitive.  Names that match other registered names in a case
      insensitive manner SHOULD NOT be accepted.

   Change Controller:
      For Standards Track RFCs, state "IETF".  For others, give the name
      of the responsible party.  Other details (e.g., postal address,
      email address, home page URI) may also be included.

   Specification Document(s):
      Reference to the document(s) that specify the parameter,
      preferably including URI(s) that can be used to retrieve copies of
      the document(s).  An indication of the relevant sections may also
      be included but is not required.

7.2.2.  Initial Registry Contents

   o  Parameter Name: "keys"
   o  Change Controller: IETF
   o  Specification Document(s): Section 4.1 of [[ this document ]]

7.3.  JSON Web Signature and Encryption Type Values Registration

7.3.1.  Registry Contents

   This specification registers the "JWK" and "JWK-SET" type values in
   the IANA JSON Web Signature and Encryption Type Values registry
   [JWS]:

   o  "typ" Header Parameter Value: "JWK"
   o  Abbreviation for MIME Type: application/jwk+json
   o  Change Controller: IETF
   o  Specification Document(s): Section 3 of [[ this document ]]

   o  "typ" Header Parameter Value: "JWK-SET"
   o  Abbreviation for MIME Type: application/jwk-set+json
   o  Change Controller: IETF
   o  Specification Document(s): Section 4 of [[ this document ]]

7.4.  Media Type Registration

7.4.1.  Registry Contents

   This specification registers the "application/jwk+json" and
   "application/jwk-set+json" Media Types [RFC2046] in the MIME Media
   Type registry [RFC4288] to indicate, respectively, that the content
   is a JWK or a JWK Set.



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   o  Type Name: application
   o  Subtype Name: jwk+json
   o  Required Parameters: n/a
   o  Optional Parameters: n/a
   o  Encoding considerations: application/jwk+json values are
      represented as JSON object; UTF-8 encoding SHOULD be employed for
      the JSON object.
   o  Security Considerations: See the Security Considerations section
      of [[ this document ]]
   o  Interoperability Considerations: n/a
   o  Published Specification: [[ this document ]]
   o  Applications that use this media type: TBD
   o  Additional Information: Magic number(s): n/a, File extension(s):
      n/a, Macintosh file type code(s): n/a
   o  Person & email address to contact for further information: Michael
      B. Jones, mbj@microsoft.com
   o  Intended Usage: COMMON
   o  Restrictions on Usage: none
   o  Author: Michael B. Jones, mbj@microsoft.com
   o  Change Controller: IETF

   o  Type Name: application
   o  Subtype Name: jwk-set+json
   o  Required Parameters: n/a
   o  Optional Parameters: n/a
   o  Encoding considerations: application/jwk-set+json values are
      represented as a JSON Object; UTF-8 encoding SHOULD be employed
      for the JSON object.
   o  Security Considerations: See the Security Considerations section
      of [[ this document ]]
   o  Interoperability Considerations: n/a
   o  Published Specification: [[ this document ]]
   o  Applications that use this media type: TBD
   o  Additional Information: Magic number(s): n/a, File extension(s):
      n/a, Macintosh file type code(s): n/a
   o  Person & email address to contact for further information: Michael
      B. Jones, mbj@microsoft.com
   o  Intended Usage: COMMON
   o  Restrictions on Usage: none
   o  Author: Michael B. Jones, mbj@microsoft.com
   o  Change Controller: IETF


8.  Security Considerations

   All of the security issues faced by any cryptographic application
   must be faced by a JWS/JWE/JWK agent.  Among these issues are
   protecting the user's private and symmetric keys, preventing various



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   attacks, and helping the user avoid mistakes such as inadvertently
   encrypting a message for the wrong recipient.  The entire list of
   security considerations is beyond the scope of this document, but
   some significant considerations are listed here.

   A key is no more trustworthy than the method by which it was
   received.

   Private and symmetric keys must be protected from disclosure to
   unintended parties.  One recommended means of doing so is to encrypt
   JWKs or JWK Sets containing them by using the JWK or JWK Set value as
   the plaintext of a JWE.

   The security considerations in RFC 3447 [RFC3447] and RFC 6030
   [RFC6030] about protecting private and symmetric keys also apply to
   this specification.

   The security considerations in XML DSIG 2.0
   [W3C.CR-xmldsig-core2-20120124], about key representations also apply
   to this specification, other than those that are XML specific.


9.  References

9.1.  Normative References

   [ITU.X690.1994]
              International Telecommunications Union, "Information
              Technology - ASN.1 encoding rules: Specification of Basic
              Encoding Rules (BER), Canonical Encoding Rules (CER) and
              Distinguished Encoding Rules (DER)", ITU-T Recommendation
              X.690, 1994.

   [JWA]      Jones, M., "JSON Web Algorithms (JWA)",
              draft-ietf-jose-json-web-algorithms (work in progress),
              May 2013.

   [JWE]      Jones, M., Rescorla, E., and J. Hildebrand, "JSON Web
              Encryption (JWE)", draft-ietf-jose-json-web-encryption
              (work in progress), May 2013.

   [JWS]      Jones, M., Bradley, J., and N. Sakimura, "JSON Web
              Signature (JWS)", draft-ietf-jose-json-web-signature (work
              in progress), May 2013.

   [RFC1421]  Linn, J., "Privacy Enhancement for Internet Electronic
              Mail: Part I: Message Encryption and Authentication
              Procedures", RFC 1421, February 1993.



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   [RFC2046]  Freed, N. and N. Borenstein, "Multipurpose Internet Mail
              Extensions (MIME) Part Two: Media Types", RFC 2046,
              November 1996.

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119, March 1997.

   [RFC2818]  Rescorla, E., "HTTP Over TLS", RFC 2818, May 2000.

   [RFC3986]  Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
              Resource Identifier (URI): Generic Syntax", STD 66,
              RFC 3986, January 2005.

   [RFC4288]  Freed, N. and J. Klensin, "Media Type Specifications and
              Registration Procedures", RFC 4288, December 2005.

   [RFC4627]  Crockford, D., "The application/json Media Type for
              JavaScript Object Notation (JSON)", RFC 4627, July 2006.

   [RFC4648]  Josefsson, S., "The Base16, Base32, and Base64 Data
              Encodings", RFC 4648, October 2006.

   [RFC5226]  Narten, T. and H. Alvestrand, "Guidelines for Writing an
              IANA Considerations Section in RFCs", BCP 26, RFC 5226,
              May 2008.

   [RFC5246]  Dierks, T. and E. Rescorla, "The Transport Layer Security
              (TLS) Protocol Version 1.2", RFC 5246, August 2008.

   [RFC5280]  Cooper, D., Santesson, S., Farrell, S., Boeyen, S.,
              Housley, R., and W. Polk, "Internet X.509 Public Key
              Infrastructure Certificate and Certificate Revocation List
              (CRL) Profile", RFC 5280, May 2008.

   [W3C.CR-xmldsig-core2-20120124]
              Eastlake, D., Reagle, J., Yiu, K., Solo, D., Datta, P.,
              Hirsch, F., Cantor, S., and T. Roessler, "XML Signature
              Syntax and Processing Version 2.0", World Wide Web
              Consortium CR CR-xmldsig-core2-20120124, January 2012,
              <http://www.w3.org/TR/2012/CR-xmldsig-core2-20120124>.

9.2.  Informative References

   [MagicSignatures]
              Panzer (editor), J., Laurie, B., and D. Balfanz, "Magic
              Signatures", January 2011.

   [RFC3447]  Jonsson, J. and B. Kaliski, "Public-Key Cryptography



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              Standards (PKCS) #1: RSA Cryptography Specifications
              Version 2.1", RFC 3447, February 2003.

   [RFC4122]  Leach, P., Mealling, M., and R. Salz, "A Universally
              Unique IDentifier (UUID) URN Namespace", RFC 4122,
              July 2005.

   [RFC6030]  Hoyer, P., Pei, M., and S. Machani, "Portable Symmetric
              Key Container (PSKC)", RFC 6030, October 2010.


Appendix A.  Example JSON Web Key Sets

A.1.  Example Public Keys

   The following example JWK Set contains two public keys represented as
   JWKs: one using an Elliptic Curve algorithm and a second one using an
   RSA algorithm.  The first specifies that the key is to be used for
   encryption.  The second specifies that the key is to be used with the
   "RS256" algorithm.  Both provide a Key ID for key matching purposes.
   In both cases, integers are represented using the base64url encoding
   of their big endian representations.  (Long lines are broken are for
   display purposes only.)

     {"keys":
       [
         {"kty":"EC",
          "crv":"P-256",
          "x":"MKBCTNIcKUSDii11ySs3526iDZ8AiTo7Tu6KPAqv7D4",
          "y":"4Etl6SRW2YiLUrN5vfvVHuhp7x8PxltmWWlbbM4IFyM",
          "use":"enc",
          "kid":"1"},

         {"kty":"RSA",
          "n": "0vx7agoebGcQSuuPiLJXZptN9nndrQmbXEps2aiAFbWhM78LhWx
     4cbbfAAtVT86zwu1RK7aPFFxuhDR1L6tSoc_BJECPebWKRXjBZCiFV4n3oknjhMs
     tn64tZ_2W-5JsGY4Hc5n9yBXArwl93lqt7_RN5w6Cf0h4QyQ5v-65YGjQR0_FDW2
     QvzqY368QQMicAtaSqzs8KJZgnYb9c7d0zgdAZHzu6qMQvRL5hajrn1n91CbOpbI
     SD08qNLyrdkt-bFTWhAI4vMQFh6WeZu0fM4lFd2NcRwr3XPksINHaQ-G_xBniIqb
     w0Ls1jF44-csFCur-kEgU8awapJzKnqDKgw",
          "e":"AQAB",
          "alg":"RS256",
          "kid":"2011-04-29"}
       ]
     }






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A.2.  Example Private Keys

   The following example JWK Set contains two keys represented as JWKs
   containing both public and private key values: one using an Elliptic
   Curve algorithm and a second one using an RSA algorithm.  This
   example extends the example in the previous section, adding private
   key values.  (Line breaks are for display purposes only.)












































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     {"keys":
       [
         {"kty":"EC",
          "crv":"P-256",
          "x":"MKBCTNIcKUSDii11ySs3526iDZ8AiTo7Tu6KPAqv7D4",
          "y":"4Etl6SRW2YiLUrN5vfvVHuhp7x8PxltmWWlbbM4IFyM",
          "d":"870MB6gfuTJ4HtUnUvYMyJpr5eUZNP4Bk43bVdj3eAE",
          "use":"enc",
          "kid":"1"},

         {"kty":"RSA",
          "n":"0vx7agoebGcQSuuPiLJXZptN9nndrQmbXEps2aiAFbWhM78LhWx4
     cbbfAAtVT86zwu1RK7aPFFxuhDR1L6tSoc_BJECPebWKRXjBZCiFV4n3oknjhMst
     n64tZ_2W-5JsGY4Hc5n9yBXArwl93lqt7_RN5w6Cf0h4QyQ5v-65YGjQR0_FDW2Q
     vzqY368QQMicAtaSqzs8KJZgnYb9c7d0zgdAZHzu6qMQvRL5hajrn1n91CbOpbIS
     D08qNLyrdkt-bFTWhAI4vMQFh6WeZu0fM4lFd2NcRwr3XPksINHaQ-G_xBniIqbw
     0Ls1jF44-csFCur-kEgU8awapJzKnqDKgw",
          "e":"AQAB",
          "d":"X4cTteJY_gn4FYPsXB8rdXix5vwsg1FLN5E3EaG6RJoVH-HLLKD9
     M7dx5oo7GURknchnrRweUkC7hT5fJLM0WbFAKNLWY2vv7B6NqXSzUvxT0_YSfqij
     wp3RTzlBaCxWp4doFk5N2o8Gy_nHNKroADIkJ46pRUohsXywbReAdYaMwFs9tv8d
     _cPVY3i07a3t8MN6TNwm0dSawm9v47UiCl3Sk5ZiG7xojPLu4sbg1U2jx4IBTNBz
     nbJSzFHK66jT8bgkuqsk0GjskDJk19Z4qwjwbsnn4j2WBii3RL-Us2lGVkY8fkFz
     me1z0HbIkfz0Y6mqnOYtqc0X4jfcKoAC8Q",
          "p":"83i-7IvMGXoMXCskv73TKr8637FiO7Z27zv8oj6pbWUQyLPQBQxtPV
     nwD20R-60eTDmD2ujnMt5PoqMrm8RfmNhVWDtjjMmCMjOpSXicFHj7XOuVIYQyqV
     WlWEh6dN36GVZYk93N8Bc9vY41xy8B9RzzOGVQzXvNEvn7O0nVbfs",
          "q":"3dfOR9cuYq-0S-mkFLzgItgMEfFzB2q3hWehMuG0oCuqnb3vobLyum
     qjVZQO1dIrdwgTnCdpYzBcOfW5r370AFXjiWft_NGEiovonizhKpo9VVS78TzFgx
     kIdrecRezsZ-1kYd_s1qDbxtkDEgfAITAG9LUnADun4vIcb6yelxk",
          "dp":"G4sPXkc6Ya9y8oJW9_ILj4xuppu0lzi_H7VTkS8xj5SdX3coE0oim
     YwxIi2emTAue0UOa5dpgFGyBJ4c8tQ2VF402XRugKDTP8akYhFo5tAA77Qe_Nmtu
     YZc3C3m3I24G2GvR5sSDxUyAN2zq8Lfn9EUms6rY3Ob8YeiKkTiBj0",
          "dq":"s9lAH9fggBsoFR8Oac2R_E2gw282rT2kGOAhvIllETE1efrA6huUU
     vMfBcMpn8lqeW6vzznYY5SSQF7pMdC_agI3nG8Ibp1BUb0JUiraRNqUfLhcQb_d9
     GF4Dh7e74WbRsobRonujTYN1xCaP6TO61jvWrX-L18txXw494Q_cgk",
          "qi":"GyM_p6JrXySiz1toFgKbWV-JdI3jQ4ypu9rbMWx3rQJBfmt0FoYzg
     UIZEVFEcOqwemRN81zoDAaa-Bk0KWNGDjJHZDdDmFhW3AN7lI-puxk_mHZGJ11rx
     yR8O55XLSe3SPmRfKwZI6yU24ZxvQKFYItdldUKGzO6Ia6zTKhAVRU",
          "alg":"RS256",
          "kid":"2011-04-29"}
       ]
     }








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A.3.  Example Symmetric Keys

   The following example JWK Set contains two symmetric keys represented
   as JWKs: one designated as being for use with the AES Key Wrap
   algorithm and a second one that is an HMAC key.  (Line breaks are for
   display purposes only.)

     {"keys":
       [
         {"kty":"oct",
          "alg":"A128KW",
          "k":"GawgguFyGrWKav7AX4VKUg"},

         {"kty":"oct",
          "k":"AyM1SysPpbyDfgZld3umj1qzKObwVMkoqQ-EstJQLr_T-1qS0gZH75
     aKtMN3Yj0iPS4hcgUuTwjAzZr1Z9CAow",
          "kid":"HMAC key used in JWS A.1 example"}
       ]
     }


Appendix B.  Example Use of "x5c" (X.509 Certificate Chain) Parameter





























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   The following is a non-normative example of a JWK with a RSA signing
   key represented both as a bare public key and as an X.509 certificate
   using the "x5c" parameter:

     {"kty":"RSA",
      "use":"sig",
      "kid":"1b94c",
      "n":"vrjOfz9Ccdgx5nQudyhdoR17V-IubWMeOZCwX_jj0hgAsz2J_pqYW08
      PLbK_PdiVGKPrqzmDIsLI7sA25VEnHU1uCLNwBuUiCO11_-7dYbsr4iJmG0Q
      u2j8DsVyT1azpJC_NG84Ty5KKthuCaPod7iI7w0LK9orSMhBEwwZDCxTWq4a
      YWAchc8t-emd9qOvWtVMDC2BXksRngh6X5bUYLy6AyHKvj-nUy1wgzjYQDwH
      MTplCoLtU-o-8SNnZ1tmRoGE9uJkBLdh5gFENabWnU5m1ZqZPdwS-qo-meMv
      VfJb6jJVWRpl2SUtCnYG2C32qvbWbjZ_jBPD5eunqsIo1vQ",
      "e":"AQAB",
      "x5c":
       ["MIIDQjCCAiqgAwIBAgIGATz/FuLiMA0GCSqGSIb3DQEBBQUAMGIxCzAJB
       gNVBAYTAlVTMQswCQYDVQQIEwJDTzEPMA0GA1UEBxMGRGVudmVyMRwwGgYD
       VQQKExNQaW5nIElkZW50aXR5IENvcnAuMRcwFQYDVQQDEw5CcmlhbiBDYW1
       wYmVsbDAeFw0xMzAyMjEyMzI5MTVaFw0xODA4MTQyMjI5MTVaMGIxCzAJBg
       NVBAYTAlVTMQswCQYDVQQIEwJDTzEPMA0GA1UEBxMGRGVudmVyMRwwGgYDV
       QQKExNQaW5nIElkZW50aXR5IENvcnAuMRcwFQYDVQQDEw5CcmlhbiBDYW1w
       YmVsbDCCASIwDQYJKoZIhvcNAQEBBQADggEPADCCAQoCggEBAL64zn8/QnH
       YMeZ0LncoXaEde1fiLm1jHjmQsF/449IYALM9if6amFtPDy2yvz3YlRij66
       s5gyLCyO7ANuVRJx1NbgizcAblIgjtdf/u3WG7K+IiZhtELto/A7Fck9Ws6
       SQvzRvOE8uSirYbgmj6He4iO8NCyvaK0jIQRMMGQwsU1quGmFgHIXPLfnpn
       fajr1rVTAwtgV5LEZ4Iel+W1GC8ugMhyr4/p1MtcIM42EA8BzE6ZQqC7VPq
       PvEjZ2dbZkaBhPbiZAS3YeYBRDWm1p1OZtWamT3cEvqqPpnjL1XyW+oyVVk
       aZdklLQp2Btgt9qr21m42f4wTw+Xrp6rCKNb0CAwEAATANBgkqhkiG9w0BA
       QUFAAOCAQEAh8zGlfSlcI0o3rYDPBB07aXNswb4ECNIKG0CETTUxmXl9KUL
       +9gGlqCz5iWLOgWsnrcKcY0vXPG9J1r9AqBNTqNgHq2G03X09266X5CpOe1
       zFo+Owb1zxtp3PehFdfQJ610CDLEaS9V9Rqp17hCyybEpOGVwe8fnk+fbEL
       2Bo3UPGrpsHzUoaGpDftmWssZkhpBJKVMJyf/RuP2SmmaIzmnw9JiSlYhzo
       4tpzd5rFXhjRbg4zW9C+2qok+2+qDM1iJ684gPHMIY8aLWrdgQTxkumGmTq
       gawR+N5MDtdPTEQ0XfIBc2cJEUyMTY5MPvACWpkA6SdS4xSvdXK3IVfOWA=="]
     }


Appendix C.  Acknowledgements

   A JSON representation for RSA public keys was previously introduced
   by John Panzer, Ben Laurie, and Dirk Balfanz in Magic Signatures
   [MagicSignatures].

   This specification is the work of the JOSE Working Group, which
   includes dozens of active and dedicated participants.  In particular,
   the following individuals contributed ideas, feedback, and wording
   that influenced this specification:




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   Dirk Balfanz, Richard Barnes, John Bradley, Brian Campbell, Breno de
   Medeiros, Joe Hildebrand, Edmund Jay, Ben Laurie, James Manger, Matt
   Miller, Tony Nadalin, Axel Nennker, John Panzer, Eric Rescorla, Nat
   Sakimura, Jim Schaad, Paul Tarjan, Hannes Tschofenig, and Sean
   Turner.

   Jim Schaad and Karen O'Donoghue chaired the JOSE working group and
   Sean Turner and Stephen Farrell served as Security area directors
   during the creation of this specification.


Appendix D.  Document History

   [[ to be removed by the RFC editor before publication as an RFC ]]

   -11

   o  Stated that when "kid" values are used within a JWK Set, different
      keys within the JWK Set SHOULD use distinct "kid" values.

   o  Added optional "x5u" (X.509 URL), "x5t" (X.509 Certificate
      Thumbprint), and "x5c" (X.509 Certificate Chain) JWK parameters.

   o  Added section on Encrypted JWK and Encrypted JWK Set Formats.

   o  Added a Parameter Information Class value to the JSON Web Key
      Parameters registry, which registers whether the parameter conveys
      public or private information.

   o  Registered "application/jwk+json" and "application/jwk-set+json"
      MIME types and "JWK" and "JWK-SET" typ header parameter values,
      addressing issue #21.

   -10

   o  No changes were made, other than to the version number and date.

   -09

   o  Expanded the scope of the JWK specification to include private and
      symmetric key representations, as specified by
      draft-jones-jose-json-private-and-symmetric-key-00.

   o  Defined that members that are not understood must be ignored.

   -08





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   o  Changed the name of the JWK key type parameter from "alg" to "kty"
      to enable use of "alg" to indicate the particular algorithm that
      the key is intended to be used with.

   o  Clarified statements of the form "This member is OPTIONAL" to "Use
      of this member is OPTIONAL".

   o  Referenced String Comparison Rules in JWS.

   o  Added seriesInfo information to Internet Draft references.

   -07

   o  Changed the name of the JWK RSA modulus parameter from "mod" to
      "n" and the name of the JWK RSA exponent parameter from "xpo" to
      "e", so that the identifiers are the same as those used in RFC
      3447.

   -06

   o  Changed the name of the JWK RSA exponent parameter from "exp" to
      "xpo" so as to allow the potential use of the name "exp" for a
      future extension that might define an expiration parameter for
      keys.  (The "exp" name is already used for this purpose in the JWT
      specification.)

   o  Clarify that the "alg" (algorithm family) member is REQUIRED.

   o  Correct an instance of "JWK" that should have been "JWK Set".

   o  Applied changes made by the RFC Editor to RFC 6749's registry
      language to this specification.

   -05

   o  Indented artwork elements to better distinguish them from the body
      text.

   -04

   o  Refer to the registries as the primary sources of defined values
      and then secondarily reference the sections defining the initial
      contents of the registries.

   o  Normatively reference XML DSIG 2.0 [W3C.CR-xmldsig-core2-20120124]
      for its security considerations.





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   o  Added this language to Registration Templates: "This name is case
      sensitive.  Names that match other registered names in a case
      insensitive manner SHOULD NOT be accepted."

   o  Described additional open issues.

   o  Applied editorial suggestions.

   -03

   o  Clarified that "kid" values need not be unique within a JWK Set.

   o  Moved JSON Web Key Parameters registry to the JWK specification.

   o  Added "Collision Resistant Namespace" to the terminology section.

   o  Changed registration requirements from RFC Required to
      Specification Required with Expert Review.

   o  Added Registration Template sections for defined registries.

   o  Added Registry Contents sections to populate registry values.

   o  Numerous editorial improvements.

   -02

   o  Simplified JWK terminology to get replace the "JWK Key Object" and
      "JWK Container Object" terms with simply "JSON Web Key (JWK)" and
      "JSON Web Key Set (JWK Set)" and to eliminate potential confusion
      between single keys and sets of keys.  As part of this change, the
      top-level member name for a set of keys was changed from "jwk" to
      "keys".

   o  Clarified that values with duplicate member names MUST be
      rejected.

   o  Established JSON Web Key Set Parameters registry.

   o  Explicitly listed non-goals in the introduction.

   o  Moved algorithm-specific definitions from JWK to JWA.

   o  Reformatted to give each member definition its own section
      heading.

   -01




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   o  Corrected the Magic Signatures reference.

   -00

   o  Created the initial IETF draft based upon
      draft-jones-json-web-key-03 with no normative changes.


Author's Address

   Michael B. Jones
   Microsoft

   Email: mbj@microsoft.com
   URI:   http://self-issued.info/




































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