    [Search] [txt|html|xml|pdfized|bibtex] [Tracker] [WG] [Email] [Diff1] [Diff2] [Nits]

    Versions: (draft-belyavskiy-epp-eai) 00 01 02 03         Standards Track
              04 05 06 07

    Network Working Group                                      D. Belyavskiy
    Internet-Draft
    Intended status: Standards Track                                J. Gould
    Expires: 25 July 2022                                     VeriSign, Inc.
                                                             21 January 2022

    Use of Internationalized Email Addresses in the Extensible Provisioning
                                 Protocol (EPP)
                          draft-ietf-regext-epp-eai-07

    Abstract

       This document describes an EPP extension that permits usage of
       Internationalized Email Addresses in the EPP protocol and specifies
       the terms when it can be used by EPP clients and servers.  The
       Extensible Provisioning Protocol (EPP), being developed before
       appearing the standards for Internationalized Email Addresses (EAI),
       does not support such email addresses.

       TO BE REMOVED on turning to RFC: The document is edited in the
       dedicated github repo (https://github.com/beldmit/eppeai).  Please
       send your submissions via GitHub.

    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 25 July 2022.

    Copyright Notice

       Copyright (c) 2022 IETF Trust and the persons identified as the
       document authors.  All rights reserved.

    Belyavskiy & Gould        Expires 25 July 2022                  [Page 1]

    Internet-Draft              Use of EAI in EPP               January 2022

       This document is subject to BCP 78 and the IETF Trust's Legal
       Provisions Relating to IETF Documents (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 Revised BSD License text as
       described in Section 4.e of the Trust Legal Provisions and are
       provided without warranty as described in the Revised BSD License.

    Table of Contents

       1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   3
         1.1.  Conventions Used in This Document . . . . . . . . . . . .   3
       2.  Migrating to Newer Versions of This Extension . . . . . . . .   3
       3.  Email Address Specification . . . . . . . . . . . . . . . . .   4
       4.  Functional Extension  . . . . . . . . . . . . . . . . . . . .   4
       5.  Internationalized Email Addresses (EAI) Functional
               Extension . . . . . . . . . . . . . . . . . . . . . . . .   5
         5.1.  Scope of Functional Extension . . . . . . . . . . . . . .   5
         5.2.  Signaling Client and Server Support . . . . . . . . . . .   5
         5.3.  Functional Extension Behavior . . . . . . . . . . . . . .   5
           5.3.1.  EAI Functional Extension Negotiated . . . . . . . . .   5
           5.3.2.  EAI Functional Extension Not Negotiated . . . . . . .   6
       6.  Security Considerations . . . . . . . . . . . . . . . . . . .   7
       7.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   7
         7.1.  XML Namespace . . . . . . . . . . . . . . . . . . . . . .   7
         7.2.  EPP Extension Registry  . . . . . . . . . . . . . . . . .   8
       8.  References  . . . . . . . . . . . . . . . . . . . . . . . . .   8
         8.1.  Normative References  . . . . . . . . . . . . . . . . . .   8
         8.2.  Informative References  . . . . . . . . . . . . . . . . .   9
       Appendix A.  Change History . . . . . . . . . . . . . . . . . . .   9
         A.1.  Change from 00 to 01  . . . . . . . . . . . . . . . . . .   9
         A.2.  Change from 01 to 02  . . . . . . . . . . . . . . . . . .   9
         A.3.  Change from 02 to 03  . . . . . . . . . . . . . . . . . .  10
         A.4.  Change from 03 to 04  . . . . . . . . . . . . . . . . . .  10
         A.5.  Change from 04 to the regext 01 version . . . . . . . . .  10
         A.6.  Change from the regext 01 to regext 02 version  . . . . .  10
         A.7.  Change from the regext 02 to regext 03 version  . . . . .  10
         A.8.  Change from the regext 03 to regext 04 version  . . . . .  10
         A.9.  Change from the regext 04 to regext 05 version  . . . . .  10
         A.10. Change from the regext 05 to regext 06 version  . . . . .  11
         A.11. Change from the regext 06 to regext 07 version  . . . . .  11
       Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  11

    Belyavskiy & Gould        Expires 25 July 2022                  [Page 2]

    Internet-Draft              Use of EAI in EPP               January 2022

    1.  Introduction

       [RFC6530] introduced the framework for Internationalized Email
       Addresses.  To make such addresses more widely accepted, the changes
       to various protocols need to be introduced.

       This document describes an Extensible Provisioning Protocol (EPP)
       extension that permits usage of Internationalized Email Addresses in
       the EPP protocol and specifies the terms when it can be used by EPP
       clients and servers.  A new form of EPP extension, referred to as a
       Functional Extension, is defined and used to apply the rules for the
       handling of email address elements in all of the [RFC5730] extensions
       negotiated in the EPP session, which include the object and command-
       responses extensions.  The described mechanism can be applied to any
       object or command-response extension that uses an email address.

       The Extensible Provisioning Protocol (EPP) specified in [RFC5730] is
       a base document for object management operations and an extensible
       framework that maps protocol operations to objects.  The specifics of
       various objects managed via EPP is described in separate documents.
       This document is only referring to an email address as a property of
       a managed object, such as the <contact:email> element in the EPP
       contact mapping [RFC5733] or the <org:email> element in the EPP
       organization mapping [RFC8543], and command-response extensions
       applied to a managed object.

    1.1.  Conventions Used in This Document

       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.

    2.  Migrating to Newer Versions of This Extension

       Servers that implement this extension SHOULD provide a way for
       clients to progressively update their implementations when a new
       version of the extension is deployed.  A newer version of the
       extension is expected to use an XML namespace with a higher version
       number than the prior versions.

    Belyavskiy & Gould        Expires 25 July 2022                  [Page 3]

    Internet-Draft              Use of EAI in EPP               January 2022

    3.  Email Address Specification

       Support of non-ASCII email address syntax is defined in RFC 6530
       [RFC6530].  This mapping does not prescribe minimum or maximum
       lengths for character strings used to represent email addresses.  The
       exact syntax of such addresses is described in Section 3.3 of
       [RFC6531].  The validation rules introduced in RFC 6531 are
       considered to be followed.

       The definition of email address in the EPP RFCs, including
       Section 2.6 of [RFC5733] and Section 4.1.2, 4.2.1, and 4.2.5 of
       [RFC8543], references [RFC5322] for the email address syntax.  The
       XML schema definition in Section 4 of [RFC5733] and Section 5 of
       [RFC8543] defines the "email" element using the type
       "eppcom:minTokenType", which is defined in Section 4.2 of [RFC5730]
       as an XML schema "token" type with minimal length of one.  The XML
       schema "token" type will fully support the use of EAI addresses, so
       the primary application of the EAI extension is to apply the use of
       [RFC6531] instead of [RFC5322] for the email address syntax.  Other
       EPP extensions may follow the formal syntax definition using the XML
       schema type "eppcom:minTokenType" and the [RFC5322] format
       specification, where this extension applies to all EPP extensions
       with the same or similar definitions.

       The email address format is formally defined in Section 3.4.1 of
       [RFC5322], which only consists of printable US-ASCII characters for
       both the local-part and the domain ABNF rules.  [RFC6531] extends the
       Mailbox, Local-part and Domain ABNF rules in [RFC5321] to support
       "UTF8-non-ascii", defined in Section 3.1 of [RFC6532], for the local-
       part and U-label, defined in Section 2.3.2.1 of [RFC5890], for the
       domain.  By applying the syntax rules of [RFC5322], the EPP
       extensions will change from supporting only ASCII characters to
       supporting Internationalized characters both in the email address
       local-part and domain-part.

    4.  Functional Extension

       [RFC5730] defines three types of extensions at the protocol, object,
       and command-response level, which impact the structure of the EPP
       messages.  A Functional Extension applies a functional capability to
       an existing set of EPP extensions and properties.  The scope of the
       applicable EPP extensions and applicable extension properties are
       defined in the Functional Extension along with the requirements for
       the servers and clients that support it.  The Functional Extension
       needs to cover the expected behavior of the supporting client or
       server when interacting with an unsupporting client or server.
       Negotiating support for a Functional Extension is handled using the
       EPP Greeting and EPP Login services.

    Belyavskiy & Gould        Expires 25 July 2022                  [Page 4]

    Internet-Draft              Use of EAI in EPP               January 2022

    5.  Internationalized Email Addresses (EAI) Functional Extension

    5.1.  Scope of Functional Extension

       The functional extension applies to all object extensions and
       command-response extensions negotiated in the EPP session that
       include email address properties.  Examples include the
       <contact:email> element in the EPP contact mapping [RFC5733] or the
       <org:email> element in the EPP organization mapping [RFC8543].  All
       registry zones (e.g., top-level domains) authorized for the client in
       the EPP session apply.  There is no concept of a per-client, per-
       zone, per-extension, or per-field setting that is used to indicate
       support for EAI, but instead it's a global setting that applies to
       the EPP session.

    5.2.  Signaling Client and Server Support

       The client and the server can signal support for the functional
       extension using a namespace URI in the login and greeting extension
       services respectively.  The namespace URI
       "urn:ietf:params:xml:ns:epp:eai-1.0" is used to signal support for
       the functional extension.  The client includes the namespace URI in
       an <svcExtension> <extURI> element of the [RFC5730] <login> Command.
       The server includes the namespace URI in an <svcExtension> <extURI>
       element of the [RFC5730] Greeting.

    5.3.  Functional Extension Behavior

    5.3.1.  EAI Functional Extension Negotiated

       If both client and server have indicated the support of the EAI
       addresses during the session establishment, it implies possibility to
       process the EAI address in any message having an email property
       during the established EPP session.  Below are the server and client
       obligations when the EAI extension has been successfuly negotiated in
       the EPP session.

       The server MUST satisfy the following obligations when the EAI
       extension has been negotiated:

       *  Accept EAI compatible addresses for all email properties in the
          EPP session negotiated object extensions and command-response
          extensions.  For example the <contact:email> element in [RFC5733]
          and the <org:email> element in [RFC8543].

       *  Accept EAI compatible addresses for all registry zones (e.g., top-
          level domains) authorized for the client in the EPP session.

    Belyavskiy & Gould        Expires 25 July 2022                  [Page 5]

    Internet-Draft              Use of EAI in EPP               January 2022

       *  Email address validation based on EAI validation rules defined in
          Section 3

       *  Storage of email properties that support internationalized
          characters.

       *  Return EAI compatible addresses for all email properties in the
          EPP responses.

       The client MUST satisfy the following obligations when THE EAI
       extension has been negotiated:

       *  Provide EAI compatible addresses for all e-mail properties in the
          EPP session negotiated object extensions and command-response
          extensions.  For example the <contact:email> element in [RFC5733]
          and the <org:email> element in [RFC8543].

       *  Provide EAI compatible addresses for all registry zones (e.g.,
          top-level domains) authorized for the client in the EPP session.

       *  Accept EAI compatible addresses in the EPP responses for all email
          properties in the EPP session negotiated object extensions and
          command-response extensions.

    5.3.2.  EAI Functional Extension Not Negotiated

       The lack of EAI support can cause data and functional issues, so an
       EAI supporting client or server needs to handle cases where the
       opposite party doesn't support EAI.  Below are the server and client
       obligations when the EAI extension is not negotiated due to the lack
       of support by the peer.

       The EAI supporting server MUST satisfy the following obligations when
       the client does not support the EAI extension:

       *  When the email property is required in the EPP command, the server
          SHOULD validate the email property sent by the client using the
          ASCII email validation rules.

       *  When the email property is optional in the EPP command, if the
          client supplies the email property the server SHOULD validate the
          email property using the ASCII email validation rules.

       *  When the email property is required in the EPP response, the
          server MUST validate whether the email property is an EAI address
          and if so return the error code 2308 "Data management policy
          violation".

    Belyavskiy & Gould        Expires 25 July 2022                  [Page 6]

    Internet-Draft              Use of EAI in EPP               January 2022

       *  When the email property is optional in the EPP response and is
          provided, the server MUST validate whether the email property is
          an EAI address and if so return the error code 2308 "Data
          management policy violation".

       The EAI supporting client MUST satisfy the following obligations when
       the server does not support the EAI extension:

       *  When the email property is required in the EPP command and the
          email property is an EAI address, the client MUST provide an ASCII
          email address.  The provided email address should provide a way to
          contact the registrant.  It can be a secondary ASCII email address
          or registrar-provided proxy email address.

       *  When the email property is optional in the EPP command and the
          email property is an EAI address with no alternative ASCII
          address, the client SHOULD omit the email property.  If the email
          property is provided, the client MUST provide an ASCII email
          address.  The provided email address should provide a way to
          contact the registrant.  It can be a secondary ASCII email address
          or registrar-provided proxy email address.

    6.  Security Considerations

       Registries SHOULD validate the domain names syntax in the provided
       email addresses to reduce the risk of future usability errors.  It is
       RECOMMENDED to validate all code points in the domain names according
       to IDNA2008 [RFC5892].

    7.  IANA Considerations

    7.1.  XML Namespace

       This document uses URNs to describe XML namespaces and XML schemas
       conforming to a registry mechanism described in RFC 3688 [RFC3688].
       The following URI assignment should be made by IANA:

       Registration request for the eai namespace:

          URI:  urn:ietf:params:xml:ns:epp:eai-1.0
          Registrant Contact:  IESG
          XML:  None.  Namespace URIs do not represent an XML specification.

          Registration request for the eai XML Schema:

          URI:  urn:ietf:params:xml:schema:epp:eai-1.0
          Registrant Contact:  IESG
          XML:  See the "Formal Syntax" section of this document.

    Belyavskiy & Gould        Expires 25 July 2022                  [Page 7]

    Internet-Draft              Use of EAI in EPP               January 2022

    7.2.  EPP Extension Registry

       The EPP extension described in this document should be registered by
       IANA in the "Extensions for the Extensible Provisioning Protocol
       (EPP)" registry described in RFC 7451 [RFC7451].  The details of the
       registration are as follows:

          Name of Extension: Use of Internationalized Email Addresses
                             in EPP protocol
          Document status:  Standards Track
          Reference:  TBA
          Registrant Name and Email Address:  IESG, <iesg@ietf.org>
          Top-Level Domains(TLDs):  Any
          IPR Disclosure:  None
          Status:  Active
          Notes:  None

    8.  References

    8.1.  Normative References

       [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
                  Requirement Levels", BCP 14, RFC 2119,
                  DOI 10.27487/RFC2119, March 1997,
                  <https://www.rfc-editor.org/info/rfc2119>.

       [RFC3688]  Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
                  DOI 10.27487/RFC3688, January 2004,
                  <https://www.rfc-editor.org/info/rfc3688>.

       [RFC5321]  Klensin, J., "Simple Mail Transfer Protocol", RFC 5321,
                  DOI 10.17487/RFC5321, October 2008,
                  <https://www.rfc-editor.org/info/rfc5321>.

       [RFC5322]  Resnick, P., Ed., "Internet Message Format", RFC 5322,
                  DOI 10.17487/RFC5322, October 2008,
                  <https://www.rfc-editor.org/info/rfc5322>.

       [RFC5730]  Hollenbeck, S., "Extensible Provisioning Protocol (EPP)",
                  STD 69, RFC 5730, DOI 10.27487/RFC5730, August 2009,
                  <https://www.rfc-editor.org/info/rfc5730>.

       [RFC5733]  Hollenbeck, S., "Extensible Provisioning Protocol (EPP)
                  Contact Mapping", STD 69, RFC 5733, DOI 10.27487/RFC5733,
                  August 2009, <https://www.rfc-editor.org/info/rfc5733>.

    Belyavskiy & Gould        Expires 25 July 2022                  [Page 8]

    Internet-Draft              Use of EAI in EPP               January 2022

       [RFC5890]  Klensin, J., "Internationalized Domain Names for
                  Applications (IDNA): Definitions and Document Framework",
                  RFC 5890, DOI 10.17487/RFC5890, August 2010,
                  <https://www.rfc-editor.org/info/rfc5890>.

       [RFC6530]  Klensin, J. and Y. Ko, "Overview and Framework for
                  Internationalized Email", RFC 6530, DOI 10.27487/RFC6530,
                  February 2012, <https://www.rfc-editor.org/info/rfc6530>.

       [RFC6531]  Yao, J. and W. Mao, "SMTP Extension for Internationalized
                  Email", RFC 6531, DOI 10.17487/RFC6531, February 2012,
                  <https://www.rfc-editor.org/info/rfc6531>.

       [RFC6532]  Yang, A., Steele, S., and N. Freed, "Internationalized
                  Email Headers", RFC 6532, DOI 10.17487/RFC6532, February
                  2012, <https://www.rfc-editor.org/info/rfc6532>.

       [RFC7451]  Hollenbeck, S., "Extension Registry for the Extensible
                  Provisioning Protocol", RFC 7451, DOI 10.27487/RFC7451,
                  February 2015, <https://www.rfc-editor.org/info/rfc7451>.

       [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
                  2119 Key Words", BCP 14, RFC 8174, DOI 10.27487/RFC8174,
                  May 2017, <https://www.rfc-editor.org/info/rfc8174>.

    8.2.  Informative References

       [RFC5892]  Faltstrom, P., Ed., "The Unicode Code Points and
                  Internationalized Domain Names for Applications (IDNA)",
                  RFC 5892, DOI 10.27487/RFC5892, August 2010,
                  <https://www.rfc-editor.org/info/rfc5892>.

       [RFC8543]  Zhou, L., Kong, N., Yao, J., Gould, J., and G. Zhou,
                  "Extensible Provisioning Protocol (EPP) Organization
                  Mapping", RFC 8543, DOI 10.27487/RFC8543, March 2019,
                  <https://www.rfc-editor.org/info/rfc8543>.

    Appendix A.  Change History

    A.1.  Change from 00 to 01

       1.  Changed from update of RFC 5733 to use the "Placeholder Text and
           a New Email Element" EPP Extension approach.

    A.2.  Change from 01 to 02

       1.  Fixed the XML schema and the XML examples based on validating
           them.

    Belyavskiy & Gould        Expires 25 July 2022                  [Page 9]

    Internet-Draft              Use of EAI in EPP               January 2022

       2.  Added James Gould as co-author.

       3.  Updated the language to apply to any EPP object mapping and to
           use the EPP contact mapping as an example.

       4.  Updated the structure of document to be consistent with the other
           Command-Response Extensions.

       5.  Replaced the use of "eppEAI" in the XML namespace and the XML
           namespace prefix with "eai".

       6.  Changed to use a pointed XML namespace with "0.2" instead of
           "1.0".

    A.3.  Change from 02 to 03

       1.  The approach has changed to use the concept of Functional EPP
           Extension.

       2.  The examples are removed

    A.4.  Change from 03 to 04

       1.  More detailed reference to email syntax is provided

       2.  The shortened eai namespace reference is removed

    A.5.  Change from 04 to the regext 01 version

       1.  Provided the recommended placeholder value

    A.6.  Change from the regext 01 to regext 02 version

       1.  Removed the concept of the placeholder value

    A.7.  Change from the regext 02 to regext 03 version

       1.  Changed to use a pointed XML namespace with "0.3" instead of
           "0.2".

       2.  Some wording improvements

    A.8.  Change from the regext 03 to regext 04 version

       1.  Some nitpicking

    A.9.  Change from the regext 04 to regext 05 version

    Belyavskiy & Gould        Expires 25 July 2022                 [Page 10]

    Internet-Draft              Use of EAI in EPP               January 2022

       1.  Some nitpicking

       2.  The "Implementation considerations" section is removed

    A.10.  Change from the regext 05 to regext 06 version

       1.  Some nitpicking

    A.11.  Change from the regext 06 to regext 07 version

       1.  Namespace version set to 1.0

    Authors' Addresses

       Dmitry Belyavskiy
       8 marta st.
       Moscow
       127083
       Russian Federation

       Phone: +7 916 262 5593
       Email: beldmit@gmail.com

       James Gould
       VeriSign, Inc.
       12061 Bluemont Way
       Reston, VA 20190
       United States of America

       Email: jgould@verisign.com
       URI:   http://www.verisigninc.com

    Belyavskiy & Gould        Expires 25 July 2022                 [Page 11]