Transport Layer Security                                      J. Salowey
Internet-Draft                                                Salesforce
Obsoletes: 8447 (if approved)                                  S. Turner
Updates: 3749, 5077, 4680, 5246, 5705, 5878,                       sn3rd
         6520, 7301 (if approved)                            8 July 2022
Intended status: Standards Track
Expires: 9 January 2023


                 IANA Registry Updates for TLS and DTLS
                      draft-ietf-tls-rfc8447bis-01

Abstract

   This document describes a number of changes to 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 TLS- and DTLS-related registries
   undertaken as part of the TLS 1.3 development process.

   This document obsoletes RFC 8447 and updates the following RFCs:
   3749, 5077, 4680, 5246, 5705, 5878, 6520, and 7301.

About This Document

   This note is to be removed before publishing as an RFC.

   Status information for this document may be found at
   https://datatracker.ietf.org/doc/draft-ietf-tls-rfc8447bis/.

   Discussion of this document takes place on the Transport Layer
   Security Working Group mailing list (mailto:tls@ietf.org), which is
   archived at https://mailarchive.ietf.org/arch/browse/tls/.

   Source for this draft and an issue tracker can be found at
   https://github.com/tlswg/rfc8447bis.

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/.





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   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 9 January 2023.

Copyright Notice

   Copyright (c) 2022 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 (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
   2.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . .   3
   3.  Adding "TLS" to Registry Names  . . . . . . . . . . . . . . .   3
   4.  Aligning with RFC 8126  . . . . . . . . . . . . . . . . . . .   4
   5.  Adding "Recommended" Column . . . . . . . . . . . . . . . . .   4
   6.  Session Ticket TLS Extension  . . . . . . . . . . . . . . . .   5
   7.  TLS ExtensionType Values  . . . . . . . . . . . . . . . . . .   5
   8.  TLS Cipher Suites Registry  . . . . . . . . . . . . . . . . .   8
   9.  TLS Supported Groups  . . . . . . . . . . . . . . . . . . . .  11
   10. TLS ClientCertificateType Identifiers . . . . . . . . . . . .  12
   11. New Session Ticket TLS Handshake Message Type . . . . . . . .  13
   12. TLS Exporter Labels Registry  . . . . . . . . . . . . . . . .  13
   13. Adding Missing Item to TLS Alerts Registry  . . . . . . . . .  15
   14. TLS Certificate Types . . . . . . . . . . . . . . . . . . . .  15
   15. Orphaned Registries . . . . . . . . . . . . . . . . . . . . .  16
   16. Additional Notes  . . . . . . . . . . . . . . . . . . . . . .  19
   17. Designated Expert Pool  . . . . . . . . . . . . . . . . . . .  20
   18. Security Considerations . . . . . . . . . . . . . . . . . . .  21
   19. IANA Considerations . . . . . . . . . . . . . . . . . . . . .  21
   20. References  . . . . . . . . . . . . . . . . . . . . . . . . .  21
     20.1.  Normative References . . . . . . . . . . . . . . . . . .  21
     20.2.  Informative References . . . . . . . . . . . . . . . . .  23
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  24





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1.  Introduction

   This document instructs IANA to make changes to a number of the IANA
   registries related to Transport Layer Security (TLS) and Datagram
   Transport Layer Security (DTLS).

      |  NOTE for IANA: Where we make new changes we used [SHALL / has].
      |  Otherwise, we left it as has, i.e., it matches the text in
      |  [RFC8447].

   Most of the instructions included herein and previously included in
   [RFC8447], which this document obsoletes, were motivated by the
   development of TLS 1.3 [RFC8446].  The changes ranged 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 the introduction, each section provides rationale
   for the proposed change(s).  The instructions in this document revise
   the values of "Recommended" column, applies the new value to the
   registries, and adds this column as noted in Section 15.  There are
   also instructions to update references, including replacing
   references to [RFC8446] with [I-D.ietf-tls-rfc8446bis] and [RFC8447]
   with [I-D.ietf-tls-rfc8447bis].

   This document proposes no changes to the registration policies for
   TLS Alerts [I-D.ietf-tls-rfc8446bis], TLS ContentType
   [I-D.ietf-tls-rfc8446bis], TLS HandshakeType
   [I-D.ietf-tls-rfc8446bis], 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.

2.  Terminology

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
   "OPTIONAL" in this document are to be interpreted as described in
   BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
   capitals, as shown here.

3.  Adding "TLS" to Registry Names

   For consistency amongst TLS registries, IANA has prepended "TLS" to
   the following registries:

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

   *  ExtensionType Values,



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   *  Heartbeat Message Types [RFC6520], and

   *  Heartbeat Modes [RFC6520].

   IANA [SHALL update/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.

4.  Aligning with RFC 8126

   Many of the TLS-related IANA registries had the registration
   procedure "IETF Consensus", which was changed to "IETF Review" by
   [RFC8126].  To align with the new terminology, IANA has updated the
   following registries to "IETF Review":

   *  TLS Authorization Data Formats [RFC4680]

   *  TLS Supplemental Data Formats (SupplementalDataType) [RFC5878]

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

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

5.  Adding "Recommended" Column

   The instructions in this document update the Recommended column,
   originally added in [RFC8447] to add a third value, "D", indicating
   that a value is "Discouraged".  The permitted values are:

   *  Y: Indicates that the IETF has consensus that the item is
      RECOMMENDED.  This only means that the associated mechanism is fit
      for the purpose for which it was defined.  Careful reading of the
      documentation for the mechanism is necessary to understand the
      applicability of that mechanism.  The IETF could recommend
      mechanisms that have limited applicability, but will provide
      applicability statements that describe any limitations of the
      mechanism or necessary constraints on its use.

   *  N: Indicates that the item has not been evaluated by the IETF and
      that the IETF has made no statement about the suitability of the
      associated mechanism.  This does not necessarily mean that the
      mechanism is flawed, only that no consensus exists.  The IETF
      might have consensus to leave an items marked as "N" on the basis
      of it having limited applicability or usage constraints.




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   *  D: Indicates that the item is discouraged and SHOULD NOT or MUST
      NOT be used.  This marking could be used to identify mechanisms
      that might result in problems if they are used, such as a weak
      cryptographic algorithm or a mechanism that might cause
      interoperability problems in deployment.

   Setting the Recommended item to "Y" or "D" or changing a item whose
   current value is "Y" or "D" requires Standards Action [RFC8126].  Not
   all items defined in Standards Track RFCs need to be marked as
   Recommended.  Changing the Recommended status of an item in a
   Standards Track RFC requires Standards Action [RFC8126].

      |  Note: the registries in the rest of the document will need to
      |  have the recommended column updated appropriately, specifically
      |  to deprecate MD5 and SHA-1, etc.

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:

   *  has renamed entry 35 to "session_ticket (renamed from
      "SessionTicket TLS")" [RFC5077].

   *  [SHALL replace/has replaced] the reference to [RFC8447] with a
      reference to this document in the "Reference" column for entry 35.

7.  TLS ExtensionType Values

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

   *  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].

   *  Updated the "Reference" to refer to this document instead of
      [RFC8447].





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   See Section 17 for additional information about the designated expert
   pool.

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

   *  Add a "Recommended" column with the contents as listed below.
      This table has been generated by marking Standards Track RFCs as
      "Y", "truncated_hmac" (4) and "connection_id (deprecated)" (53) as
      "D", and all others as "N".  The "Recommended" column is assigned
      a value of "N" unless explicitly requested, and adding a value
      with a "Recommended" value of "Y" requires Standards Action
      [RFC8126].  IESG Approval is REQUIRED for a Y->N, Y->D, and D->Y|N
      transitions.

      |  Note: Should we also mark the Reserved 40 and 46 as "D"?

         +========================================+=============+
         | Extension                              | Recommended |
         +========================================+=============+
         | server_name                            |           Y |
         +----------------------------------------+-------------+
         | max_fragment_length                    |           N |
         +----------------------------------------+-------------+
         | client_certificate_url                 |           Y |
         +----------------------------------------+-------------+
         | trusted_ca_keys                        |           Y |
         +----------------------------------------+-------------+
         | truncated_hmac                         |           D |
         +----------------------------------------+-------------+
         | status_request                         |           Y |
         +----------------------------------------+-------------+
         | user_mapping                           |           Y |
         +----------------------------------------+-------------+
         | client_authz                           |           N |
         +----------------------------------------+-------------+
         | server_authz                           |           N |
         +----------------------------------------+-------------+
         | cert_type                              |           N |
         +----------------------------------------+-------------+
         | supported_groups                       |           Y |
         +----------------------------------------+-------------+
         | ec_point_formats                       |           Y |
         +----------------------------------------+-------------+
         | srp                                    |           N |
         +----------------------------------------+-------------+



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         | signature_algorithms                   |           Y |
         +----------------------------------------+-------------+
         | use_srtp                               |           Y |
         +----------------------------------------+-------------+
         | heartbeat                              |           Y |
         +----------------------------------------+-------------+
         | application_layer_protocol_negotiation |           Y |
         +----------------------------------------+-------------+
         | status_request_v2                      |           Y |
         +----------------------------------------+-------------+
         | signed_certificate_timestamp           |           N |
         +----------------------------------------+-------------+
         | client_certificate_type                |           Y |
         +----------------------------------------+-------------+
         | server_certificate_type                |           Y |
         +----------------------------------------+-------------+
         | padding                                |           Y |
         +----------------------------------------+-------------+
         | encrypt_then_mac                       |           Y |
         +----------------------------------------+-------------+
         | extended_master_secret                 |           Y |
         +----------------------------------------+-------------+
         | cached_info                            |           Y |
         +----------------------------------------+-------------+
         | session_ticket                         |           Y |
         +----------------------------------------+-------------+
         | renegotiation_info                     |           Y |
         +----------------------------------------+-------------+
         | connection_id (deprecated)             |           D |
         +----------------------------------------+-------------+

                                 Table 1

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

   Note:  The role of the designated expert is described in
      [I-D.ietf-tls-rfc8447bis].  The designated expert [RFC8126]
      ensures that the 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
      more 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






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      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:  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 IETF consensus process, has
      limited applicability, or is intended only for specific use cases.

   The extensions added by [I-D.ietf-tls-rfc8446bis] are omitted from
   the above table.  Likewise, extensions defined after [RFC8447] are
   also not listed in the table as those RFCs specify the value of the
   extension's "Recommended"; extensions points defined after [RFC8447]
   include token_binding, compress_certificate, record_size_limit,
   pwd_protect, pwd_clear, password_salt, ticket_pinning,
   tls_cert_with_extern_psk, delegated_credentials,
   supported_ekt_ciphers, connection_id, external_id_hash,
   external_session_id, quic_transport_parameters, ticket_request, and
   dnssec_chain.

   [I-D.ietf-tls-rfc8446bis] also uses the TLS ExtensionType Values
   registry originally created in [RFC4366].  The following text is from
   [I-D.ietf-tls-rfc8446bis] and is included here to ensure alignment
   between these specifications.

   *  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_cert", extensions with the values
      defined in [I-D.ietf-tls-rfc8446bis] and the "Recommended" value
      of "Y".

   *  IANA [SHALL update/has updated] this registry to include a "TLS
      1.3" column that lists the messages in which the extension may
      appear.  This column [SHALL be/has been] initially populated from
      the table in Section 4.2 of [I-D.ietf-tls-rfc8446bis] with any
      extension not listed there marked as "-" to indicate that it is
      not used by TLS 1.3.

8.  TLS Cipher Suites Registry

      |  Note: Review in light of [I-D.ietf-tls-deprecate-obsolete-kex].

   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 Suites registry's registration



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   policy to Specification Required while reserving a small part of the
   code space for Experimental and Private Use [RFC8126].  Therefore,
   IANA has updated the TLS Cipher Suites registry's policy as follows:

       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].

   See Section 17 for additional information about the designated expert
   pool.

   The 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] the TLS Cipher Suites registry
   as follows:

      |  The following text needs to be update to reflect the new
      |  recommended policy.

   *  Added a "Recommended" column to the TLS Cipher Suites registry.
      The cipher suites that follow in the two tables are marked as "Y".
      All other cipher suites are marked as "N".  The "Recommended"
      column is assigned a value of "N" unless explicitly requested, and
      adding a value with a "Recommended" value of "Y" requires
      Standards Action [RFC8126].  IESG Approval is REQUIRED for a Y->N
      transition.

      The cipher suites that follow are Standards Track server-
      authenticated (and optionally client-authenticated) cipher suites
      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}




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   The cipher suites that follow are Standards Track ephemeral pre-
   shared key cipher suites that are 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_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         | {0xD0,0x01}
   TLS_ECDHE_PSK_WITH_AES_256_GCM_SHA384         | {0xD0,0x02}
   TLS_ECDHE_PSK_WITH_AES_128_CCM_SHA256         | {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 [I-D.ietf-tls-rfc8446bis] 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, and some
   implementers blindly implement cipher suites.  Therefore, IANA 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 has added the following note to ensure that those that focus on
   IANA registries are aware that TLS 1.3 [I-D.ietf-tls-rfc8446bis] 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 and hash functions, 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] the following notes to document the rules
   for populating the "Recommended" column:

   Note:  CCM_8 cipher suites are not marked as "Recommended".  These



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      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", it does not
      necessarily mean that it is flawed; rather, it indicates that 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] the following notes for additional
   information:

   Note:  The role of the designated expert is described in
      [I-D.ietf-tls-rfc8447bis].  The designated expert [RFC8126]
      ensures that the 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
      more 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] the reference for this registry to
   refer to this document instead of [RFC8447].

9.  TLS Supported Groups

   Similar to cipher suites, supported groups have proliferated over
   time, and some use the registry to measure implementations.
   Therefore, IANA [SHALL add/has added] a "Recommended" column with a
   "Y" for secp256r1, secp384r1, x25519, and x448, while all others are
   "N".  These "Y" groups are taken from Standards Track RFCs; [RFC8422]
   elevates secp256r1 and secp384r1 to Standards Track.  Not all groups
   from [RFC8422], which is Standards Track, are marked as "Y"; these
   groups apply to TLS 1.3 [I-D.ietf-tls-rfc8446bis] and previous
   versions of TLS.  The "Recommended" column is assigned a value of "N"
   unless explicitly requested, and adding a value with a "Recommended"
   value of "Y" requires Standards Action [RFC8126].  IESG Approval is
   REQUIRED for a Y->N transition.

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

   Note:  If an item is not marked as "Recommended" it does not



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      necessarily mean that it is flawed; rather, it indicates that 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 designated expert is described in
      [I-D.ietf-tls-rfc8447bis].  The designated expert [RFC8126]
      ensures that the 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
      more in-depth reviews, but their approval should not be taken as
      an endorsement of the supported groups.

   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, and some
   implementers blindly implement supported group.  Therefore, IANA has
   added the following warning to the registry:

   WARNING:  Cryptographic algorithms and parameters will be broken or
      weakened over time.  Blindly implementing 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] the reference for this registry to
   refer to this document instead of [RFC8447].

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

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 while reserving some of the code space for
   Standards Track usage and a small part of the code space for Private
   Use [RFC8126].  Therefore, IANA has updated the TLS
   ClientCertificateType Identifiers registry's policy as follows:

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

   See Section 17 for additional information about the designated expert
   pool.

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



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   Note:  The role of the designated expert is described in
      [I-D.ietf-tls-rfc8447bis].  The designated expert [RFC8126]
      ensures that the 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
      more 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.

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:

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

   *  [SHALL replace/has replaced] a reference to [RFC8447] with a
      reference to this document in the "Reference" column for entry 4
      in the TLS HandshakeType registry.

12.  TLS Exporter Labels Registry

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

   *  The following note to the TLS Exporter Labels registry:

      Note:  [RFC5705] defines keying material exporters for TLS in
         terms of the TLS PRF.  [I-D.ietf-tls-rfc8446bis] replaced the
         PRF with HKDF, thus requiring a new construction.  The exporter
         interface remains the same; however, the value is computed
         differently.

   *  A "Recommended" column to the TLS Exporter Labels registry.  The
      table that follows has been generated by marking Standards Track
      RFCs as "Y" and all others as "N".  The "Recommended" column is
      assigned a value of "N" unless explicitly requested, and adding a
      value with a "Recommended" value of "Y" requires Standards Action
      [RFC8126].  IESG Approval is REQUIRED for a Y->N, Y->D, or D->Y|N
      transitions.




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

                                  Table 2

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

   Note:  The role of the designated expert is described in
      [I-D.ietf-tls-rfc8447bis].  The designated expert [RFC8126]
      ensures that the 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
      more in-depth reviews, but their approval should not be taken as
      an endorsement of the 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:  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 IETF consensus process, has
      limited applicability, or is intended only for specific use cases.





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   IANA [SHALL update/has updated] the reference for this registry to
   refer to refer to this document instead of [RFC8447].

13.  Adding Missing Item to TLS Alerts Registry

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

       120   no_application_protocol  Y  [RFC7301][This-document]

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
   while reserving a small part of the code space for Private Use
   [RFC8126].  Therefore, IANA has changed the TLS Certificate Types
   registry as follows:

   *  Changed the registry policy to:

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

   *  Added a "Recommended" column to the registry.  X.509 and Raw
      Public Key are "Y".  All others are "N".  The "Recommended" column
      is assigned a value of "N" unless explicitly requested, and adding
      a value with a "Recommended" value of "Y" requires Standards
      Action [RFC8126].  IESG Approval is REQUIRED for a Y->N, Y->D, and
      D->Y|N transitions.

   See Section 17 for additional information about the designated expert
   pool.

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

   Note:  The role of the designated expert is described in
      [I-D.ietf-tls-rfc8447bis].  The designated expert [RFC8126]
      ensures that the 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
      more in-depth reviews, but their approval should not be taken as
      an endorsement of the certificate type.

   Note:  If an item is not marked as "Recommended", it does not




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      necessarily mean that it is flawed; rather, it indicates that 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] the reference for this registry to
   refer this document instead of [RFC8447].

15.  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:

   *  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.

   *  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.

   *  [SHALL update/has updated] the "Reference" field in the TLS
      Compression Method Identifiers, TLS HashAlgorithm and TLS
      SignatureAlgorithm registries to refer to this document instead of
      [RFC8447].

   *  has updated the TLS HashAlgorithm 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".

   *  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 has added the
   following warning to the TLS HashAlgorithm and SignatureAlgorithm
   registries:




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   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.

   Though TLS 1.0 and TLS 1.1 were deprecated [RFC8996], TLS 1.2 will be
   in use for some time.  IANA [SHALL update/has updated] the TLS
   HashAlgorithm, TLS SignatureAlgorithm, and TLS ClientCertificateTypes
   registries to add a "Recommended" column as follows:

   TLS HashAlgorithm registry:

                      +==============+=============+
                      | Descsription | Recommended |
                      +==============+=============+
                      | none         |           Y |
                      +--------------+-------------+
                      | md5          |           D |
                      +--------------+-------------+
                      | sha1         |           D |
                      +--------------+-------------+
                      | sha224       |           D |
                      +--------------+-------------+
                      | sha256       |           Y |
                      +--------------+-------------+
                      | sha384       |           Y |
                      +--------------+-------------+
                      | sha512       |           Y |
                      +--------------+-------------+
                      | Intrinsic    |           Y |
                      +--------------+-------------+

                                 Table 3

   TLS SignatureAlgorithm registry:















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                    +===================+=============+
                    | Descsription      | Recommended |
                    +===================+=============+
                    | anonymous         |           N |
                    +-------------------+-------------+
                    | rsa               |           Y |
                    +-------------------+-------------+
                    | dsa               |           N |
                    +-------------------+-------------+
                    | ecdsa             |           Y |
                    +-------------------+-------------+
                    | ed25519           |           Y |
                    +-------------------+-------------+
                    | ed448             |           Y |
                    +-------------------+-------------+
                    | gostr34102012_256 |           N |
                    +-------------------+-------------+
                    | gostr34102012_512 |           N |
                    +-------------------+-------------+

                                  Table 4

   TLS ClientCertificateTypes registry:




























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                +===========================+=============+
                | Descsription              | Recommended |
                +===========================+=============+
                | rsa_sign                  |           Y |
                +---------------------------+-------------+
                | dss_sign                  |           N |
                +---------------------------+-------------+
                | rsa_fixed_dh              |           N |
                +---------------------------+-------------+
                | dss_fixed_dh              |           N |
                +---------------------------+-------------+
                | rsa_ephemeral_dh_RESERVED |           D |
                +---------------------------+-------------+
                | dss_ephemeral_dh_RESERVED |           D |
                +---------------------------+-------------+
                | fortezza_dms_RESERVED     |           D |
                +---------------------------+-------------+
                | ecdsa_sign                |           Y |
                +---------------------------+-------------+
                | rsa_fixed_ecdh            |           N |
                +---------------------------+-------------+
                | ecdsa_fixed_ecdh          |           N |
                +---------------------------+-------------+
                | gost_sign256              |           N |
                +---------------------------+-------------+
                | gost_sign512              |           N |
                +---------------------------+-------------+

                                  Table 5

   In the TLS HashAlgorithm, TLS SignatureAlgorithm, and TLS
   ClientCertificateTypes registries, all unassigned and reserved values
   have a "Recommended" that is blank.

16.  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





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      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] 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 IETF consensus process, has
      limited applicability, or is intended only for specific use cases.

   Note:  The role of the designated expert is described in
      [I-D.ietf-tls-rfc8447bis].  The designated expert [RFC8126]
      ensures that the 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
      more in depth reviews, but their approval should not be taken as
      an endorsement of the key exchange mode.

17.  Designated Expert Pool

   Specification Required [RFC8126] registry requests are registered
   after a three-week review period on the tls-reg-review@ietf.org
   (mailto:tls-reg-review@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 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 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 (mailto:iesg@ietf.org) mailing list) for resolution.








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   Criteria that SHOULD be applied by the 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
   and SHOULD direct all requests for registration to the review mailing
   list.

   It is suggested that multiple 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.

18.  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; however, cryptographic algorithms and
   parameters will be broken or weakened over time.  It is possible that
   the "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 reviews.  Their review should not be
   taken as an endorsement of the cipher suite, extension, supported
   group, etc.

19.  IANA Considerations

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

20.  References

20.1.  Normative References




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   [I-D.ietf-tls-deprecate-obsolete-kex]
              Bartle, C. and N. Aviram, "Deprecating Obsolete Key
              Exchange Methods in TLS", Work in Progress, Internet-
              Draft, draft-ietf-tls-deprecate-obsolete-kex-00, 15 June
              2022, <https://datatracker.ietf.org/doc/html/draft-ietf-
              tls-deprecate-obsolete-kex-00>.

   [I-D.ietf-tls-rfc8446bis]
              Rescorla, E., "The Transport Layer Security (TLS) Protocol
              Version 1.3", Work in Progress, Internet-Draft, draft-
              ietf-tls-rfc8446bis-04, 7 March 2022,
              <https://datatracker.ietf.org/doc/html/draft-ietf-tls-
              rfc8446bis-04>.

   [I-D.ietf-tls-rfc8447bis]
              Salowey, J. and S. Turner, "IANA Registry Updates for TLS
              and DTLS", Work in Progress, Internet-Draft, draft-ietf-
              tls-rfc8447bis-00, 29 March 2022,
              <https://datatracker.ietf.org/doc/html/draft-ietf-tls-
              rfc8447bis-00>.

   [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/rfc/rfc2119>.

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

   [RFC4680]  Santesson, S., "TLS Handshake Message for Supplemental
              Data", RFC 4680, DOI 10.17487/RFC4680, October 2006,
              <https://www.rfc-editor.org/rfc/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/rfc/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/rfc/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/rfc/rfc5705>.




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   [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/rfc/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/rfc/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/rfc/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/rfc/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/rfc/rfc8174>.

   [RFC8996]  Moriarty, K. and S. Farrell, "Deprecating TLS 1.0 and TLS
              1.1", BCP 195, RFC 8996, DOI 10.17487/RFC8996, March 2021,
              <https://www.rfc-editor.org/rfc/rfc8996>.

20.2.  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/rfc/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/rfc/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, August 2018,
              <https://www.rfc-editor.org/rfc/rfc8422>.






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   [RFC8446]  Rescorla, E., "The Transport Layer Security (TLS) Protocol
              Version 1.3", RFC 8446, DOI 10.17487/RFC8446, August 2018,
              <https://www.rfc-editor.org/rfc/rfc8446>.

   [RFC8447]  Salowey, J. and S. Turner, "IANA Registry Updates for TLS
              and DTLS", RFC 8447, DOI 10.17487/RFC8447, August 2018,
              <https://www.rfc-editor.org/rfc/rfc8447>.

Authors' Addresses

   Joe Salowey
   Salesforce
   Email: joe@salowey.net


   Sean Turner
   sn3rd
   Email: sean@sn3rd.com

































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