TLS WG
Internet Engineering Task Force (IETF)                        J. Salowey
Internet-Draft
Request for Comments: 8447                              Tableau Software
Updates: 3749, 5077, 4680, 5246, 5705,                         S. Turner
         5878, 6520, 7301 (if approved)                                          sn3rd
Intended status:
Category: Standards Track                            May 24, 2018
Expires: November 25,                                    August 2018
ISSN: 2070-1721

                 IANA Registry Updates for Transport Layer Security (TLS) TLS and Datagram
                    Transport Layer Security (DTLS)
                draft-ietf-tls-iana-registry-updates-05 DTLS

Abstract

   This document describes a number of changes to (D)TLS TLS and DTLS IANA
   registries that range from adding notes to the registry all the way
   to changing the registration policy.  These changes were mostly
   motivated by WG review of the (D)TLS-related TLS- and DTLS-related registries
   undertaken as part of the
   TLS1.3 TLS 1.3 development process.

   This document updates the following RFCs: 3749, 5077, 4680, 5246,
   5705, 5878, 6520, and 7301.

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 an Internet Standards Track document.

   This document is a product of the Internet Engineering Task Force
   (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list  It represents the consensus of current Internet-
   Drafts is at http://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid the IETF community.  It has
   received public review and has been approved for a maximum publication by the
   Internet Engineering Steering Group (IESG).  Further information on
   Internet Standards is available in Section 2 of RFC 7841.

   Information about the current status of six months this document, any errata,
   and how to provide feedback on it may be updated, replaced, or obsoleted by other documents obtained 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 25, 2018.
   https://www.rfc-editor.org/info/rfc8447.

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   document authors.  All rights reserved.

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Table of Contents

   1.  Process Note  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   3.
   2.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . .   3
   4.  Add
   3.  Adding "TLS" to Registry Names  . . . . . . . . . . . . . . . . .   3
   5.
   4.  Aligning with RFC 8126  . . . . . . . . . . . . . . . . . . .   3
   6.
   5.  Adding Recommended "Recommended" Column . . . . . . . . . . . . . . . . . .   4
   7.
   6.  Session Ticket TLS Extension  . . . . . . . . . . . . . . . .   4
   8.
   7.  TLS ExtensionType Values  . . . . . . . . . . . . . . . . . .   4
   9.
   8.  TLS Cipher Suite Suites Registry  . . . . . . . . . . . . . . . . . .   7
   10.
   9.  TLS Supported Groups  . . . . . . . . . . . . . . . . . . . .  10
   11.   9
   10. TLS ClientCertificateType Identifiers . . . . . . . . . . . .  11
   12.  10
   11. New Session Ticket TLS Handshake Message Type . . . . . . . .  12
   13.  11
   12. TLS Exporter Label Labels Registry  . . . . . . . . . . . . . . . . .  12
   14. Add  11
   13. Adding Missing Item to TLS Alert Alerts Registry  . . . . . . . . . . .  14
   15.  12
   14. TLS Certificate Types . . . . . . . . . . . . . . . . . . . .  14
   16.  13
   15. Orphaned Extensions . . . . . . . . . . . . . . . . . . . . .  15
   17.  13
   16. Orphaned Registries . . . . . . . . . . . . . . . . . . . . .  14
   17. Additional Notes  . . . . . . . . . . . . . . . . . . . . . .  15
   18. Designated Expert Pool  . . . . . . . . . . . . . . . . . . .  16  15
   19. Security Considerations . . . . . . . . . . . . . . . . . . .  17  16
   20. IANA Considerations . . . . . . . . . . . . . . . . . . . . .  17
   21. References  . . . . . . . . . . . . . . . . . . . . . . . . .  17
     21.1.  Normative References . . . . . . . . . . . . . . . . . .  17
     21.2.  Informative References . . . . . . . . . . . . . . . . .  19  18
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  19

1.  Process Note

   As the authors of  Introduction

   Per this draft are also the WG chairs, the responsible
   Area Director document, IANA has agreed to judge consensus.

   RFC EDITOR: Please delete section prior to publication.

2.  Introduction

   This document instructs IANA to make changes made changes to a number of IANA
   registries related to Transport Layer Security (TLS) and Datagram
   Transport Layer Security ((D)TLS) related
   IANA registries. (DTLS).  These changes were almost entirely
   motivated by the development of TLS1.3 [I-D.ietf-tls-tls13]. TLS 1.3 [RFC8446].

   The changes introduced by this document range from simple, e.g.,
   adding notes, to complex, e.g., changing a registry's registration
   policy.  Instead of listing the changes and their rationale here in this,
   the introductory section, introduction, each section provides rationale for the proposed
   change(s).

   This document proposes no changes to the registration policies for
   TLS Alert [I-D.ietf-tls-tls13], Alerts [RFC8446], TLS ContentType [I-D.ietf-tls-tls13], [RFC8446], TLS HandshakeType [I-D.ietf-tls-tls13],
   [RFC8446], and TLS Certificate Status Types [RFC6961] registries; the
   existing policies (Standards Action for the first three; IETF Review
   for the last), are appropriate for these one-byte code points because
   of their scarcity.

3.

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.

4.  Add

3.  Adding "TLS" to Registry Names

   For consistency amongst TLS registries, IANA [SHALL prepend/has
   prepended] has prepended "TLS" to
   the following registries:

   o  Application-Layer Protocol Negotiation (ALPN) Protocol IDs
      [RFC7301],

   o  ExtensionType Values,

   o  Heartbeat Message Types [RFC6520], and

   o  Heartbeat Modes [RFC6520].

   IANA [SHALL update/has updated] has updated the reference for these four registries to also
   refer to this document.  The remainder of this document will use the
   registry names with the "TLS" prefix.

5.

4.  Aligning with RFC 8126

   Many of the TLS-related IANA registries were defined prior to
   [RFC8126] where had the registration
   procedure "IETF Consensus" Consensus", which was used instead of the
   RFC8126-defined changed to "IETF Review". Review" by
   [RFC8126].  To align with the new terminology, IANA [SHALL update/has updated] has updated the
   following registries to use "IETF
   Review" in place of "IETF Consensus": Review":

   o  TLS Authorization Data Formats [RFC4680]

   o  TLS Supplemental Data Formats (SupplementalDataType) [RFC5878]

   This is not a universal change change, as some registries originally defined
   with "IETF Consensus" are undergoing other changes either as a result
   of this document document, [RFC8446], or [I-D.ietf-tls-rfc4492bis]. [RFC8422].

   IANA [SHALL update/has updated] has updated the reference for these two registries to also refer
   to this document.

6.

5.  Adding Recommended "Recommended" Column

   The instructions in

   Per this document add document, a Recommended "Recommended" column has been added to many of
   the TLS registries to indicate parameters that are generally
   recommended for implementations to support.  Adding a Recommended "Recommended"
   parameter (i.e., "Y") to a registry or updating a parameter to Recommended
   "Recommended" status requires standards action. Standards Action.  Not all parameters
   defined in standards
   track Standards Track documents need to be marked as Recommended.
   "Recommended".

   If an item is not marked as Recommended "Recommended" (i.e., "N"), it does not
   necessarily mean that it is flawed, flawed; rather, it indicates that either the
   item either has not been through the IETF consensus process, has
   limited applicability, or is intended only for specific use cases.

7.

6.  Session Ticket TLS Extension

   The nomenclature for the registry entries in the TLS ExtensionType
   Values registry correspond to the presentation language field name
   except for entry 35.  To ensure that the values in the registry are
   consistently identified in the registry, IANA:

   o  [SHALL rename/has renamed]  has renamed entry 35 to "session_ticket (renamed from
      "SessionTicket TLS")" [RFC5077].

   o  [SHALL add/has added]  has added a reference to this document in the
      Reference "Reference" column
      for entry 35.

8.

7.  TLS ExtensionType Values

   Experience has shown that the IETF Review registry policy for TLS
   Extensions
   extensions was too strict.  Based on WG consensus, the decision was
   taken to change the registration policy to Specification Required
   [RFC8126] while reserving a small part of the code space for
   experimental and private
   use.  Therefore, IANA [SHALL update/has
   updated] has updated the TLS ExtensionType Values
   registry to: as follows:

   o  Change  Changed the registry policy to:

      Values with the first byte in the range 0-254 (decimal) are
      assigned via Specification Required [RFC8126].  Values with the
      first byte 255 (decimal) are reserved for Private Use [RFC8126].

   o  Update  Updated the "Reference" to also refer to this document.

   See Section 18 for additional information about the designated expert
   pool.

   Despite wanting to "loosen" the registration policies for TLS
   Extensions,
   extensions, it is still useful to indicate in the IANA registry which
   extensions the WG recommends be supported.  Therefore, IANA [SHALL
   update/has updated] has
   updated the TLS ExtensionType Values registry to: as follows:

   o  Add  Added a "Recommended" column with the contents as listed below.
      This table has been generated by marking Standards Track RFCs as
      "Yes"
      "Y" and all others as "No".  Future extensions MUST define the "N".  The "Recommended" column is assigned a
      value of the Recommended column.  In order to register an
      extension with the "N" unless explicitly requested, and adding a value "Yes", with
      a "Recommended" value of "Y" requires Standards Track document
      [RFC8126] is REQUIRED. Action [RFC8126].
      IESG Approval is REQUIRED for a Yes->No Y->N transition.

         +----------------------------------------+-------------+
         | Extension                              | Recommended |
         +----------------------------------------+-------------+
         | server_name                            |         Yes           Y |
         |                                        |             |
         | max_fragment_length                    |         Yes           N |
         |                                        |             |
         | client_certificate_url                 |         Yes           Y |
         |                                        |             |
         | trusted_ca_keys                        |         Yes           Y |
         |                                        |             |
         | truncated_hmac                         |         Yes           Y |
         |                                        |             |
         | status_request                         |         Yes           Y |
         |                                        |             |
         | user_mapping                           |         Yes           Y |
         |                                        |             |
         | client_authz                           |          No           N |
         |                                        |             |
         | server_authz                           |          No           N |
         |                                        |             |
         | cert_type                              |         Yes           N |
         |                                        |             |
         | supported_groups                       |         Yes           Y |
         |                                        |             |
         | ec_point_formats                       |         Yes           Y |
         |                                        |             |
         | srp                                    |          No           N |
         |                                        |             |
         | signature_algorithms                   |         Yes           Y |
         |                                        |             |
         | use_srtp                               |         Yes           Y |
         |                                        |             |
         | heartbeat                              |         Yes           Y |
         |                                        |             |
         | application_layer_protocol_negotiation |         Yes           Y |
         |                                        |             |
         | status_request_v2                      |         Yes           Y |
         |                                        |             |
         | signed_certificate_timestamp           |          No           N |
         |                                        |             |
         | client_certificate_type                |         Yes           Y |
         |                                        |             |
         | server_certificate_type                |         Yes           Y |
         |                                        |             |
         | padding                                |         Yes           Y |
         |                                        |             |
         | encrypt_then_mac                       |         Yes           Y |
         |                                        |             |
         | extended_master_secret                 |         Yes           Y |
         |                                        |             |
         | cached_info                            |         Yes           Y |
         |                                        |             |
         | session_ticket                         |         Yes           Y |
         |                                        |             |
         | renegotiation_info                     |         Yes           Y |
         +----------------------------------------+-------------+

   IANA [SHALL update/has added] has added the following notes:

   Note:  The role of the designature designated expert is described in [this-RFC]. RFC 8447.
      The designated expert [RFC8126] ensures that the specification is
      publicly available.  An Internet Draft that  It is sufficient to have an Internet-Draft
      (that is posted and never published as an RFC) or a standard in document from
      another standards body, industry consortium, university site, etc. suffices.
      The expert may provide more in depth in-depth reviews, but their approval
      should not be taken as an endorsement of the extension.

   Note:  As specified in [RFC8126], assignments made in the Private Use
      space are not generally useful for broad interoperability.  It is
      the responsibility of those making use of the Private Use range to
      ensure that no conflicts occur (within the intended scope of use).
      For widespread experiments, temporary reservations are available.

   Note:  Extensions marked as "Yes" are those allocated via Standards
      Track RFCs.  Extensions marked as "No" are not.

   Note:  If an item is not marked as Recommended "Recommended", it does not
      necessarily mean that it is flawed; rather, it indicates that
      either the
      item either has not been through the IETF consensus process, has
      limited applicability, or is intended only for specific use cases.

   NOTE:  token_binding is

   The extensions added by [RFC8446] are omitted from the above table;
      [I-D.ietf-tokbind-negotiation]
   additionally, token_binding is omitted, since [TOKBIND] specifies the Recommended
   value of the "Recommended" column for this extension.

   NOTE:

   [RFC8446] also uses the TLS ExtensionType Values registry originally
   created in [RFC4366].  The following text is from [I-D.ietf-tls-tls13] [RFC8446] and is
   included here to ensure alignment between these specifications.

   [I-D.ietf-tls-tls13] also uses the TLS ExtensionType Registry
   originally created in [RFC4366].

   o  IANA has updated it to reference
   this document.  The registry and its allocation policy is listed
   below:

   o  IANA [SHALL update/has updated] this registry to include the "key_share",
      "pre_shared_key", "psk_key_exchange_modes", "early_data",
      "cookie", "supported_versions", "certificate_authorities",
      "oid_filters", "post_handshake_auth", and "signature_algorithms_certs",
      "signature_algorithms_cert" extensions with the values defined in this document
      [RFC8446] and the Recommended "Recommended" value of "Yes". "Y".

   o  IANA [SHALL update/has updated] has updated this registry to include a "TLS 1.3" column which that
      lists the messages in which the extension may appear.  This column [SHALL be/has been]
      has been initially populated from the table in Section 4.2 of [I-D.ietf-tls-tls13]
      [RFC8446] with any extension not listed there marked as "-" to
      indicate that it is not used by TLS 1.3.

9.

8.  TLS Cipher Suite Suites Registry

   Experience has shown that the IETF Consensus registry policy for TLS
   Cipher Suites was too strict.  Based on WG consensus, the decision
   was taken to change the TLS Cipher Suite Suites registry's registration
   policy to Specification Required [RFC8126] while reserving a small
   part of the code space for experimental and private use.  Therefore, IANA [SHALL update/has updated] has updated
   the TLS Cipher Suite Suites registry's policy as follows:

      Values with the first byte in the range 0-254 (decimal) are
      assigned via Specification Required {{RFC8126}}. [RFC8126].  Values with the
      first byte 255 (decimal) are reserved for Private Use {{RFC8126}}. [RFC8126].

   See Section 18 for additional information about the designated expert
   pool.

   The cipher suite TLS Cipher Suites registry has grown significantly and will
   continue to do so.  To better guide those not intimately involved in
   TLS, IANA
   [shall update/has updated] has updated the TLS Cipher Suite Suites registry as follows:

   o  Add  Added a "Recommended" column to the TLS Cipher Suite Suites registry.
      The cipher suites that follow in the two tables are marked as "Yes". "Y".
      All other cipher suites are marked as "No".  Future cipher suites
      MUST define the "N".  The "Recommended"
      column is assigned a value of the Recommended column.  In order to
      register an extension with the "N" unless explicitly requested, and
      adding a value "Yes, with a "Recommended" value of "Y" requires
      Standards Track
      document [RFC8126] is REQUIRED. Action [RFC8126].  IESG Approval is REQUIRED for a
      Yes->No Y->N
      transition.

   The cipher suites that follow are standards track Standards Track server-
   authenticated (and optionally client-authenticated) cipher suites
      which
   that are currently available in TLS 1.2.

   RFC EDITOR: The previous paragraph is for document reviewers and is
   not meant for the registry.

   Cipher Suite Name                             | Value
   ----------------------------------------------+------------
   TLS_DHE_RSA_WITH_AES_128_GCM_SHA256           | {0x00,0x9E}
   TLS_DHE_RSA_WITH_AES_256_GCM_SHA384           | {0x00,0x9F}
   TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256       | {0xC0,0x2B}
   TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384       | {0xC0,0x2C}
   TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256         | {0xC0,0x2F}
   TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384         | {0xC0,0x30}
   TLS_DHE_RSA_WITH_AES_128_CCM                  | {0xC0,0x9E}
   TLS_DHE_RSA_WITH_AES_256_CCM                  | {0xC0,0x9F}
   TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256   | {0xCC,0xA8}
   TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256 | {0xCC,0xA9}
   TLS_DHE_RSA_WITH_CHACHA20_POLY1305_SHA256     | {0xCC,0xAA}

   The cipher suites that follow are standards track Standards Track ephemeral pre-
   shared key cipher suites which that are available in TLS 1.2.  [RFC6655]
   is inconsistent with respect to the ordering of components within PSK
   AES CCM cipher suite names; those names are used here without
   modification.

   RFC EDITOR: The previous paragraph is for document reviewers and is
   not meant for the registry.

   Cipher Suite Name                             | Value
   ----------------------------------------------+------------
   TLS_DHE_PSK_WITH_AES_128_GCM_SHA256           | {0x00,0xAA}
   TLS_DHE_PSK_WITH_AES_256_GCM_SHA384           | {0x00,0xAB}
   TLS_DHE_PSK_WITH_AES_128_CCM                  | {0xC0,0xA6}
   TLS_DHE_PSK_WITH_AES_256_CCM                  | {0xC0,0xA7}
   TLS_ECDHE_PSK_WITH_AES_128_GCM_SHA256         | {TBD} {0xD0,0x01}
   TLS_ECDHE_PSK_WITH_AES_256_GCM_SHA384         | {TBD} {0xD0,0x02}
   TLS_ECDHE_PSK_WITH_AES_128_CCM_SHA256         | {TBD} {0xD0,0x05}
   TLS_ECDHE_PSK_WITH_CHACHA20_POLY1305_SHA256   | {0xCC,0xAC}
   TLS_DHE_PSK_WITH_CHACHA20_POLY1305_SHA256     | {0xCC,0xAD}

   The TLS 1.3 cipher suites specified by [RFC8446] are not listed here;
   that document provides for their "Recommended" status.

   Despite the following behavior being misguided, experience has shown
   that some customers use the IANA registry as a checklist against
   which to measure an implementation's completeness completeness, and some
   implementers blindly implement cipher suites.  Therefore, IANA [SHALL add/has
   added] has
   added the following warning to the registry:

   WARNING:  Cryptographic algorithms and parameters will be broken or
      weakened over time.  Blindly implementing cipher suites listed
      here is not advised.  Implementers and users need to check that
      the cryptographic algorithms listed continue to provide the
      expected level of security.

   IANA [SHALL add/has added] has added the following note to ensure that those that focus on
   IANA registries are aware that TLS 1.3
   [I-D.ietf-tls-tls13] [RFC8446] uses the same
   registry but defines ciphers differently:

   Note:  Although TLS 1.3 uses the same cipher suite space as previous
      versions of TLS, TLS 1.3 cipher suites are defined differently,
      only specifying the symmetric ciphers, ciphers and hash function, and
      cannot be used for TLS 1.2.  Similarly, TLS 1.2 and lower cipher
      suite values cannot be used with TLS 1.3.

   IANA [SHALL add/has added] has added the following notes to document the rules for
   populating the Recommended "Recommended" column:

   Note:  Cipher suites marked as "Yes" are those allocated via
      Standards Track RFCs.  Cipher suites marked as "No" are not;
      cipher suites marked "No" range from "good" to "bad" from a
      cryptographic standpoint.

   Note:  CCM_8 cipher suites are not marked as Recommended. "Recommended".  These
      cipher suites have a significantly truncated authentication tag
      that represents a security trade-off that may not be appropriate
      for general environments.

   Note:  If an item is not marked as Recommended "Recommended", it does not
      necessarily mean that it is flawed; rather, it indicates that
      either the
      item either has not been through the IETF consensus process, has
      limited applicability, or is intended only for specific use cases.

   IANA [SHALL add/has added] has added the following notes for additional information:

   Note:  The role of the designature designated expert is described in [this-RFC]. RFC 8447.
      The designated expert [RFC8126] ensures that the specification is
      publicly available.  An Internet Draft that  It is sufficient to have an Internet-Draft
      (that is posted and never published as an RFC) or a standard in document from
      another standards body, industry consortium, university site, etc. suffices.
      The expert may provide more in depth in-depth reviews, but their approval
      should not be taken as an endorsement of the cipher suite.

   Note:  As specified in [RFC8126], assignments made in the Private Use
      space are not generally useful for broad interoperability.  It is
      the responsibility of those making use of the Private Use range to
      ensure that no conflicts occur (within the intended scope of use).
      For widespread experiments, temporary reservations are available.

   IANA [SHALL update/has updated] has updated the reference for this registry to also refer to
   this document.

10.

9.  TLS Supported Groups

   Similar to cipher suites, supported groups have proliferated over
   time
   time, and some use the registry to measure implementations.
   Therefore, IANA [SHALL add/has added] has added a "Recommended" column with a
   "Yes" "Y" for
   secp256r1, secp384r1, x25519, and x448 x448, while all others are
   "No". "N".
   These "Yes" "Y" groups are taken from Standards Track RFCs;
   [I-D.ietf-tls-rfc4492bis] [RFC8422]
   elevates secp256r1 and secp384r1 to Standards Track.  Not all groups
   from [I-D.ietf-tls-rfc4492bis], [RFC8422], which is standards track, Standards Track, are marked as "Yes"; "Y"; these
   groups apply to TLS 1.3 [I-D.ietf-tls-tls13] [RFC8446] and previous versions of TLS.  Future
   supported groups MUST define the  The
   "Recommended" column is assigned a value of this column.  In order to
   register an extension with the "N" unless explicitly
   requested, and adding a value "Yes", with a "Recommended" value of "Y"
   requires Standards Track
   document [RFC8126] is REQUIRED. Action [RFC8126].  IESG Approval is REQUIRED for a
   Yes->No
   Y->N transition.

   IANA [SHALL add/has added] has added the following note:

   Note:  Supported Groups marked as "Yes" are those allocated via
      Standards Track RFCs.  Supported Groups marked as "No" are not;
      supported groups marked "No" range from "good" to "bad" from a
      cryptographic standpoint. notes:

   Note:  If an item is not marked as Recommended "Recommended", it does not
      necessarily mean that it is flawed; rather, it indicates that
      either the
      item either has not been through the IETF consensus process, has
      limited applicability, or is intended only for specific use cases.

   Note:  The role of the designature designated expert is described in [this-RFC]. RFC 8447.
      The designated expert [RFC8126] ensures that the specification is
      publicly available.  An Internet Draft that  It is sufficient to have an Internet-Draft
      (that is posted and never published as an RFC) or a standard in document from
      another standards body, industry consortium, university site, etc. suffices.
      The expert may provide more in depth in-depth reviews, but their approval
      should not be taken as an endorsement of the supported group.

   Despite the following behavior being misguided, experience has shown
   that some customers use the IANA registry as a checklist against
   which to measure an implementation's completeness completeness, and some
   implementers blindly implement groups supported. supported groups.  Therefore, IANA [SHALL add/has
   added] has
   added the following warning to the registry:

   WARNING:  Cryptographic algorithms and parameters will be broken or
      weakened over time.  Blindly implementing cipher suites supported groups listed
      here is not advised.  Implementers and users need to check that
      the cryptographic algorithms listed continue to provide the
      expected level of security.

   IANA [SHALL update/has updated] has updated the reference for this registry to also refer to
   this document.

   The value 0 (0x0000) is to be has been marked as reserved.

11.

10.  TLS ClientCertificateType Identifiers

   Experience has shown that the IETF Consensus registry policy for TLS
   ClientCertificateType Identifiers is too strict.  Based on WG
   consensus, the decision was taken to change the registration policy
   to Specification Required [RFC8126] while reserving some of the code
   space for Standards Track usage and a small part of the code space
   for experimental and private use.  Therefore, IANA [SHALL
   update/has updated] has updated the TLS Cipher Suite
   ClientCertificateType Identifiers registry's policy as follows:

      Values in the range 0-223 0-63 are assigned via Standards Action.
      Values 64-223 are assigned via Specification Required [RFC8126].
      Values 224-255 are reserved for Private Use.

   See Section 18 for additional information about the designated expert
   pool.

   IANA [SHALL add/has added] has added the following notes:

   Note:  The role of the designature designated expert is described in [this-RFC]. RFC 8447.
      The designated expert [RFC8126] ensures that the specification is
      publicly available.  An Internet Draft that  It is sufficient to have an Internet-Draft
      (that is posted and never published as an RFC) or a standard in document from
      another standards body, industry consortium, university site, etc. suffices.
      The expert may provide more in depth in-depth reviews, but their approval
      should not be taken as an endorsement of the identifier.

   Note:  As specified in [RFC8126], assignments made in the Private Use
      space are not generally useful for broad interoperability.  It is
      the responsibility of those making use of the Private Use range to
      ensure that no conflicts occur (within the intended scope of use).
      For widespread experiments, temporary reservations are available.

   Note:  ClientCertificateType Identifiers marked as "Yes" are those
      allocated via Standards Track RFCs.  ClientCertificateTypes marked
      as "No" are not.

   Note:  If an item is not marked as Recommended it does not
      necessarily mean that it is flawed; rather, it indicates that
      either the item has not been through the IETF consensus process,
      has limited applicability, or is intended only for specific use
      cases.

12.

11.  New Session Ticket TLS Handshake Message Type

   To align with TLS implementations and to align the naming
   nomenclature with other Handshake message types, IANA:

   o  [SHALL rename/has renamed]  has renamed entry 4 in the TLS HandshakeType registry to
      "new_session_ticket (renamed from NewSessionTicket)" [RFC5077].

   o  [SHALL add/has added]  has added a reference to this document in the
      Reference "Reference" column
      for entry 4 in the TLS HandshakeType registry.

13.

12.  TLS Exporter Label Labels Registry

   To aid those reviewers who start with the IANA registry, IANA [SHALL
   add/has added]: has
   added:

   o  The following note to the TLS Exporter Label Registry: Labels registry:

   Note:  [RFC5705] defines keying material exporters for TLS in terms
      of the TLS PRF.  [I-D.ietf-tls-tls13]  [RFC8446] replaced the PRF with HKDF, thus
      requiring a new construction.  The exporter interface remains the same, however
      same; however, the value is computed differently.

   o  A "Recommended" column to the TLS Exporter Label Labels registry.  The
      table that follows has been generated by marking Standards Track
      RFCs as "Yes" "Y" and all others as "No".  Future exporters MUST
      define the "N".  The "Recommended" column is
      assigned a value of this column.  In order to register an
      extension with the "N" unless explicitly requested, and adding a
      value "Yes", with a "Recommended" value of "Y" requires Standards Track document
      [RFC8126] is REQUIRED. Action
      [RFC8126].  IESG Approval is REQUIRED for a Yes->No Y->N transition.

   Exporter Value                  | Recommended |
   --------------------------------|-------------|
   client finished                 |         Yes           Y |
   server finished                 |         Yes           Y |
   master secret                   |         Yes           Y |
   key expansion                   |         Yes           Y |
   client EAP encryption           |         Yes           Y |
   ttls keying material            |         Yes           N |
   ttls challenge                  |         Yes           N |
   EXTRACTOR-dtls_srtp             |         Yes           Y |
   EXPORTER_DTLS_OVER_SCTP         |         Yes           Y |
   EXPORTER: teap session key seed |         Yes           Y |

   To provide additional information for the designated experts, IANA
   [SHALL add/has added]
   has added the following note: notes:

   Note:  The role of the designature designated expert is described in [this-RFC]. RFC 8447.
      The designated expert [RFC8126] ensures that the specification is
      publicly available.  An Internet Draft that  It is sufficient to have an Internet-Draft
      (that is posted and never published as an RFC) or a standard in document from
      another standards body, industry consortium, university site, etc. suffices.
      The expert may provide more in depth in-depth reviews, but their approval
      should not be taken as an endorsement of the exporter. exporter label.  The
      expert also verifies that the label is a string consisting of
      printable ASCII characters beginning with "EXPORTER".  IANA MUST
      also verify that one label is not a prefix of any other label.
      For example, labels "key" or "master secretary" are forbidden.

   Note:  Exporters Labels marked as "Yes" are those allocated via
      Standards Track RFCs.  Exporter Labels marked as "No" are not.

   Note:  If an item is not marked as Recommended "Recommended", it does not
      necessarily mean that it is flawed; rather, it indicates that
      either the
      item either has not been through the IETF consensus process, has
      limited applicability, or is intended only for specific use cases.

   IANA [SHALL update/has updated] has updated the reference for this registry to also refer to
   this document.

14.  Add

13.  Adding Missing Item to TLS Alert Alerts Registry

   IANA [SHALL add/has added] has added the following entry to the TLS Alert
   Registry; Alerts registry; the
   entry was omitted from the IANA instructions in [RFC7301]:

   120   no_application_protocol  Y  [RFC7301][this-RFC]

15.  [RFC7301] [RFC8447]

14.  TLS Certificate Types

   Experience has shown that the IETF Consensus registry policy for TLS
   Certificate Types is too strict.  Based on WG consensus, the decision
   was taken to change registration policy to Specification Required
   [RFC8126] while reserving a small part of the code space for
   experimental and private
   use.  Therefore, IANA [SHALL change/has
   changed] has changed the TLS Certificate Types regisry to: registry
   as follows:

   o  Change  Changed the registry policy to:

      Values with the first byte in the range 0-223 (decimal) are assigned via Specification
      Required [RFC8126].  Values with in the
      first byte range 224-255 (decimal) are
      reserved for Private Use [RFC8126].

   o  Add  Added a "Recommended" column to the registry.  X.509 and Raw
      Public Key are "Yes". "Y".  All others are "No".  In order to register an
      extension with the "N".  The "Recommended" column
      is assigned a value "Yes", of "N" unless explicitly requested, and adding
      a Standards Track document
      [RFC8126] is REQUIRED.  Future Certificate Types MUST define the value of this column.  A Standards Track document [RFC8126] is
      REQUIRED to register an entry with the a "Recommended" value "Yes". of "Y" requires Standards
      Action [RFC8126].  IESG Approval is REQUIRED for a Yes->No Y->N
      transition.

   See Section 18 for additional information about the designated expert
   pool.

   IANA [SHALL add/has added] has added the following note: notes:

   Note:  The role of the designature designated expert is described in [this-RFC]. RFC 8447.
      The designated expert [RFC8126] ensures that the specification is
      publicly available.  An Internet Draft that  It is sufficient to have an Internet-Draft
      (that is posted and never published as an RFC) or a standard in document from
      another standards body, industry consortium, university site, etc. suffices.
      The expert may provide more in depth in-depth reviews, but their approval
      should not be taken as an endorsement of the certificate type.

   Note:  Certificate Types marked as "Yes" are those allocated via
      Standards Track RFCs.  Certificate Types marked as "No" are not.

   Note:  If an item is not marked as Recommended "Recommended", it does not
      necessarily mean that it is flawed; rather, it indicates that
      either the
      item either has not been through the IETF consensus process, has
      limited applicability, or is intended only for specific use cases.

   IANA [SHALL update/has updated] has updated the reference for this registry to also refer this
   document.

16.

15.  Orphaned Extensions

   To make it clear that (D)TLS 1.3 has orphaned certain extensions
   (i.e., some extensions are only applicable to version of (D)TLS prior
   to 1.3), IANA [SHALL add/has added] has added the following note to the TLS ExtensionType
   Values registry:

   Note:  The following extensions are only applicable to (D)TLS
      protocol versions prior to 1.3: trusted_ca_keys, truncated_hmac,
      user_mapping, cert_type, ec_point_formats, srp, status_request_v2,
      encrypt_then_mac, extended_master_secret, session_ticket,
      renegotiation_info, client_certificate_url, client_authz,
      server_authz, and
      renegotiation_info. cached_info.  These extensions are not
      applicable to (D)TLS 1.3.

17.

16.  Orphaned Registries

   To make it clear that (D)TLS 1.3 has orphaned certain registries
   (i.e., they are only applicable to version of (D)TLS protocol
   versions prior to 1.3), IANA:

   o  [SHALL add/has added]  has added the following to the TLS Compression Method Identifiers
      registry [RFC3749]:

   Note:  Value 0 (NULL) is the only value in this registry applicable
      to (D)TLS protocol version 1.3 or later.

   o  [SHALL add/has added]  has added the following to the TLS HashAlgorithm [RFC5246] and TLS
      SignatureAlgorithm registries [RFC5246]:

   Note:  The values in this registry are only applicable to (D)TLS
      protocol versions prior to 1.3.  (D)TLS 1.3 and later versions'
      values are registered in the TLS SignatureScheme registry.

   o  [SHALL update/has updated]  has updated the "Reference" field in the TLS Compression Method
      Identifiers, TLS HashAlgorithm and TLS SignatureAlgorithm
      registries to also refer to this document.

   o  [SHALL update/has updated]  has updated the TLS HashAlgorithm Registry registry to list values 7 and
      9-223 as "Reserved" and the TLS SignatureAlgorithm registry to
      list values 4-6 and 9-223 as "Reserved".

   o  has added the following to the TLS ClientCertificateType
      Identifiers registry [RFC5246]:

   Note:  The values in this registry are only applicable to (D)TLS
      protocol versions prior to 1.3.

   Despite the fact that the TLS HashAlgorithm and SignatureAlgorithm
   registries are orphaned, it is still important to warn implementers
   of pre-TLS1.3 implementations about the dangers of blindly
   implementing cryptographic algorithms.  Therefore, IANA [SHALL add/ has added] added the
   following warning to the TLS HashAlgorithm and SignatureAlgorithm
   registries:

   WARNING:  Cryptographic algorithms and parameters will be broken or
      weakened over time.  Blindly implementing the cryptographic
      algorithms listed here is not advised.  Implementers and users
      need to check that the cryptographic algorithms listed continue to
      provide the expected level of security.

17.  Additional Notes

   IANA has added the following warning and note to the TLS
   SignatureScheme registry:

   WARNING:  Cryptographic algorithms and parameters will be broken or
      weakened over time.  Blindly implementing signature schemes listed
      here is not advised.  Implementers and users need to check that
      the cryptographic algorithms listed continue to provide the
      expected level of security.

   Note:  As specified in [RFC8126], assignments made in the Private Use
      space are not generally useful for broad interoperability.  It is
      the responsibility of those making use of the Private Use range to
      ensure that no conflicts occur (within the intended scope of use).
      For widespread experiments, temporary reservations are available.

   IANA has added the following notes to the TLS PskKeyExchangeMode
   registry:

   Note:  If an item is not marked as "Recommended", it does not
      necessarily mean that it is flawed; rather, it indicates that the
      item either has not been through the HashAlgorithm and
   SignatureAlgorithm:

   WARNING:  Cryptographic algorithms and parameters will be broken IETF consensus process, has
      limited applicability, or
      weakened over time.  Blindly implementing is intended only for specific use cases.

   Note:  The role of the cryptographic
      algorithms listed here designated expert is not advised.  Implementers and users
      need to check described in RFC 8447.
      The designated expert [RFC8126] ensures that the cryptographic algorithms listed continue specification is
      publicly available.  It is sufficient to have an Internet-Draft
      (that is posted and never published as an RFC) or a document from
      another standards body, industry consortium, university site, etc.
      The expert may provide the expected level more in depth reviews, but their approval
      should not be taken as an endorsement of security. the key exchange mode.

18.  Designated Expert Pool

   Specification Required [RFC8126] registry requests are registered
   after a three-week review period on the tls-reg-review@ietf.org <tls-reg-review@ietf.org>
   mailing list, on the advice of one or more Designated Experts. designated experts.
   However, to allow for the allocation of values prior to publication,
   the Designated Experts designated experts may approve registration once they are
   satisfied that such a specification will be published.

   Registration requests sent to the mailing list for review SHOULD use
   an appropriate subject (e.g., "Request to register value in TLS bar
   registry").

   Within the review period, the Designated Experts designated experts will either approve
   or deny the registration request, communicating this decision to the
   review list and IANA.  Denials SHOULD include an explanation and, if
   applicable, suggestions as to how to make the request successful.
   Registration requests that are undetermined for a period longer than
   21 days can be brought to the IESG's attention (using the
   iesg@ietf.org
   <iesg@ietf.org> mailing list) for resolution.

   Criteria that SHOULD be applied by the Designated Experts designated experts includes
   determining whether the proposed registration duplicates existing
   functionality, whether it is likely to be of general applicability or
   useful only for a single application, and whether the registration
   description is clear.

   IANA MUST only accept registry updates from the Designated Experts designated experts
   and SHOULD direct all requests for registration to the review mailing
   list.

   It is suggested that multiple Designated Experts designated experts be appointed who are
   able to represent the perspectives of different applications using
   this specification, in order to enable broadly informed review of
   registration decisions.  In cases where a registration decision could
   be perceived as creating a conflict of interest for a particular
   Expert, that Expert SHOULD defer to the judgment of the other
   Experts.

19.  Security Considerations

   The change to Specification Required from IETF Review lowers the
   amount of review provided by the WG for cipher suites and supported
   groups.  This change reflects reality in that the WG essentially
   provided no cryptographic review of the cipher suites or supported
   groups.  This was especially true of national cipher suites.

   Recommended algorithms are regarded as secure for general use at the
   time of registration, registration; however, cryptographic algorithms and
   parameters will be broken or weakened over time.  It is possible that
   the Recommended "Recommended" status in the registry lags behind the most recent
   advances in cryptanalysis.  Implementers and users need to check that
   the cryptographic algorithms listed continue to provide the expected
   level of security.

   Designated experts ensure the specification is publicly available.
   They may provide more in depth in-depth reviews.  Their review should not be
   taken as an endorsement of the cipher suite, extension, supported
   group, etc.

20.  IANA Considerations

   This document is entirely about changes to TLS-related IANA
   registries.

21.  References

21.1.  Normative References

   [I-D.ietf-tls-tls13]
              Rescorla, E., "The Transport Layer Security (TLS) Protocol
              Version 1.3", draft-ietf-tls-tls13-28 (work in progress),
              March 2018.

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997, <https://www.rfc-
              editor.org/info/rfc2119>.
              <https://www.rfc-editor.org/info/rfc2119>.

   [RFC3749]  Hollenbeck, S., "Transport Layer Security Protocol
              Compression Methods", RFC 3749, DOI 10.17487/RFC3749, May
              2004, <https://www.rfc-editor.org/info/rfc3749>.

   [RFC4680]  Santesson, S., "TLS Handshake Message for Supplemental
              Data", RFC 4680, DOI 10.17487/RFC4680, October 2006,
              <https://www.rfc-editor.org/info/rfc4680>.

   [RFC5077]  Salowey, J., Zhou, H., Eronen, P., and H. Tschofenig,
              "Transport Layer Security (TLS) Session Resumption without
              Server-Side State", RFC 5077, DOI 10.17487/RFC5077,
              January 2008, <https://www.rfc-editor.org/info/rfc5077>.

   [RFC5246]  Dierks, T. and E. Rescorla, "The Transport Layer Security
              (TLS) Protocol Version 1.2", RFC 5246,
              DOI 10.17487/RFC5246, August 2008, <https://www.rfc-
              editor.org/info/rfc5246>.
              <https://www.rfc-editor.org/info/rfc5246>.

   [RFC5705]  Rescorla, E., "Keying Material Exporters for Transport
              Layer Security (TLS)", RFC 5705, DOI 10.17487/RFC5705,
              March 2010, <https://www.rfc-editor.org/info/rfc5705>.

   [RFC5878]  Brown, M. and R. Housley, "Transport Layer Security (TLS)
              Authorization Extensions", RFC 5878, DOI 10.17487/RFC5878,
              May 2010, <https://www.rfc-editor.org/info/rfc5878>.

   [RFC6520]  Seggelmann, R., Tuexen, M., and M. Williams, "Transport
              Layer Security (TLS) and Datagram Transport Layer Security
              (DTLS) Heartbeat Extension", RFC 6520,
              DOI 10.17487/RFC6520, February 2012, <https://www.rfc-
              editor.org/info/rfc6520>.

   [RFC6655]  McGrew, D. and D. Bailey, "AES-CCM Cipher Suites for
              Transport Layer Security (TLS)", RFC 6655,
              DOI 10.17487/RFC6655, July 2012, <https://www.rfc-
              editor.org/info/rfc6655>.
              <https://www.rfc-editor.org/info/rfc6520>.

   [RFC7301]  Friedl, S., Popov, A., Langley, A., and E. Stephan,
              "Transport Layer Security (TLS) Application-Layer Protocol
              Negotiation Extension", RFC 7301, DOI 10.17487/RFC7301,
              July 2014, <https://www.rfc-editor.org/info/rfc7301>.

   [RFC8126]  Cotton, M., Leiba, B., and T. Narten, "Guidelines for
              Writing an IANA Considerations Section in RFCs", BCP 26,
              RFC 8126, DOI 10.17487/RFC8126, June 2017,
              <https://www.rfc-editor.org/info/rfc8126>.

   [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
              2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
              May 2017, <https://www.rfc-editor.org/info/rfc8174>.

21.2.  Informative References

   [I-D.ietf-tls-rfc4492bis]
              Nir, Y., Josefsson, S., and M. Pegourie-Gonnard, "Elliptic
              Curve Cryptography (ECC) Cipher Suites for

   [RFC8446]  Rescorla, E., "The Transport Layer Security (TLS) Versions 1.2 and Earlier", draft-ietf-tls-
              rfc4492bis-17 (work in progress), May 2017.

   [I-D.ietf-tokbind-negotiation]
              Popov, A., Nystrom, M., Balfanz, D., and A. Langley,
              "Transport Layer Security (TLS) Extension for Token
              Binding Protocol Negotiation", draft-ietf-tokbind-
              negotiation-14 (work in progress), May 2018.
              Version 1.3", RFC 8446, DOI 10.17487/RFC8446, Month 2018,
              <https://www.rfc-editor.org/info/rfc8446>.

21.2.  Informative References

   [RFC4366]  Blake-Wilson, S., Nystrom, M., Hopwood, D., Mikkelsen, J.,
              and T. Wright, "Transport Layer Security (TLS)
              Extensions", RFC 4366, DOI 10.17487/RFC4366, April 2006,
              <https://www.rfc-editor.org/info/rfc4366>.

   [RFC6961]  Pettersen, Y., "The Transport Layer Security (TLS)
              Multiple Certificate Status Request Extension", RFC 6961,
              DOI 10.17487/RFC6961, June 2013, <https://www.rfc-
              editor.org/info/rfc6961>.
              <https://www.rfc-editor.org/info/rfc6961>.

   [RFC8422]  Nir, Y., Josefsson, S., and M. Pegourie-Gonnard, "Elliptic
              Curve Cryptography (ECC) Cipher Suites for Transport Layer
              Security (TLS) Versions 1.2 and Earlier", RFC 8422,
              DOI 10.17487/RFC8422, Month 2018,
              <https://www.rfc-editor.org/info/rfc8422>.

   [TOKBIND]  Popov, A., Nystrom, M., Balfanz, D., and A. Langley,
              "Transport Layer Security (TLS) Extension for Token
              Binding Protocol Negotiation", Work in Progress,
              draft-ietf-tokbind-negotiation-14, May 2018.

Authors' Addresses

   Joe Salowey
   Tableau Software

   Email: joe@salowey.net

   Sean Turner
   sn3rd

   Email: sean@sn3rd.com