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Updates to the TLS Transport Model for SNMP
draft-ietf-opsawg-tlstm-update-14

The information below is for an old version of the document.
Document Type
This is an older version of an Internet-Draft that was ultimately published as RFC 9456.
Author Kenneth Vaughn
Last updated 2023-04-25 (Latest revision 2023-03-30)
Replaces draft-vaughn-tlstm-update
RFC stream Internet Engineering Task Force (IETF)
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Stream WG state Submitted to IESG for Publication
Document shepherd Joe Clarke
Shepherd write-up Show Last changed 2022-10-09
IESG IESG state Became RFC 9456 (Proposed Standard)
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Telechat date (None)
Responsible AD Robert Wilton
Send notices to jclarke@cisco.com
IANA IANA review state IANA OK - Actions Needed
IANA action state RFC-Ed-Ack
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Details
draft-ietf-opsawg-tlstm-update-14
Internet Engineering Task Force                           K. Vaughn, Ed.
Internet-Draft                                              Trevilon LLC
Updates: 6353 (if approved)                                30 March 2023
Intended status: Standards Track                                        
Expires: 1 October 2023

              Updates to the TLS Transport Model for SNMP
                   draft-ietf-opsawg-tlstm-update-14

Abstract

   This document updates RFC 6353 "Transport Layer Security (TLS)
   Transport Model for the Simple Network Management Protocol (SNMP)",
   to reflect changes necessary to support Transport Layer Security
   Version 1.3 (TLS 1.3) and Datagram Transport Layer Security Version
   1.3 (DTLS 1.3), which are jointly known as "(D)TLS 1.3".  This
   document is compatible with (D)TLS 1.2 and is intended to be
   compatible with future versions of SNMP and (D)TLS.

   This document updates the SNMP-TLS-TM-MIB as defined in RFC 6353.

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at https://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on 1 October 2023.

Copyright Notice

   Copyright (c) 2023 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

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   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  . . . . . . . . . . . . . . . . . . . . . . . .   2
     1.1.  Conventions . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Changes from RFC 6353 . . . . . . . . . . . . . . . . . . . .   3
     2.1.  TLSTM Fingerprint . . . . . . . . . . . . . . . . . . . .   4
     2.2.  Security Level  . . . . . . . . . . . . . . . . . . . . .   5
     2.3.  (D)TLS Version  . . . . . . . . . . . . . . . . . . . . .   6
   3.  Additional Rules for TLS 1.3  . . . . . . . . . . . . . . . .   6
     3.1.  Zero Round Trip Time Resumption (0-RTT) . . . . . . . . .   6
     3.2.  TLS cipher suites, extensions and protocol invariants . .   6
   4.  MIB Module Definition . . . . . . . . . . . . . . . . . . . .   7
   5.  Security Considerations . . . . . . . . . . . . . . . . . . .  30
   6.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  30
   7.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .  31
   8.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  31
     8.1.  Normative References  . . . . . . . . . . . . . . . . . .  31
     8.2.  Informative References  . . . . . . . . . . . . . . . . .  33
   Author's Address  . . . . . . . . . . . . . . . . . . . . . . . .  34

1.  Introduction

   This document updates and clarifies how the rules of [RFC6353] apply
   when using Transport Layer Security (TLS) or Datagram Transport Layer
   Security (DTLS) versions later than 1.2.  This document jointly
   refers to these two protocols as "(D)TLS".  The update also
   emphasizes the [RFC8996] requirement that prohibits the use of TLS
   versions prior to TLS 1.2 when using SNMP.  Although the text of this
   document specifically references SNMPv3 and (D)TLS 1.3, this document
   may be applicable to future versions of these protocols and is
   backwards compatible with (D)TLS 1.2.

1.1.  Conventions

   Within this document the terms "TLS", "DTLS", and "(D)TLS" apply to
   all versions of the indicated protocols.  The term "SNMP" means
   "SNMPv3" unless a specific version number is indicated.  Specific
   version numbers are used when the text needs to emphasize version
   numbers.

   For consistency with SNMP-related specifications, this document
   favors terminology as defined in [STD62], rather than favoring
   terminology that is consistent with non-SNMP specifications.  This is

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   consistent with the IESG decision to not require the SNMP terminology
   be modified to match the usage of other non-SNMP specifications when
   SNMP was advanced to a Full Standard.  "Authentication" in this
   document typically refers to the English meaning of "serving to prove
   the authenticity of" the message, not data source authentication or
   peer identity authentication.  The terms "manager" and "agent" are
   not used in this document because, in the RFC3411 architecture, all
   SNMP entities have the capability of acting as manager, agent, or
   both depending on the SNMP application types supported in the
   implementation.  Where distinction is necessary, the application
   names of command generator, command responder, notification
   originator, notification receiver, and proxy forwarder are used.  See
   "SNMP Applications" (RFC3411) for further information.

   Throughout this document, the terms "client" and "server" are used to
   refer to the two ends of the TLS transport connection.  The client
   actively opens the TLS connection, and the server passively listens
   for the incoming TLS connection.  An SNMP entity MAY act as a TLS
   client or server or both, depending on the SNMP applications
   supported.

   Throughout this document, the term "session" is used to refer to a
   secure association between two instances of the TLS Transport Model
   (TLSTM) that permits the transmission of one or more SNMP messages
   within the lifetime of the session.  The TLS protocol also has an
   internal notion of a session and although these two concepts of a
   session are related, when the term "session" is used this document is
   referring to the TLSTM's specific session and not directly to the TLS
   protocol's session.

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

2.  Changes from RFC 6353

   This document updates [RFC6353].  The changes from [RFC6353] are
   defined in the following clauses.

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2.1.  TLSTM Fingerprint

   [RFC6353] defines a fingerprint algorithm that references the one-
   octet TLS 1.2 hash algorithm identifier.  TLS 1.3 replaced the one-
   octet hash algorithm identifier with a two-octet TLS 1.3 cipher suite
   identifier.  The TLS community does not plan to ever add additional
   values to the TLS 1.2 hash algorithm registry because some might
   incorrectly infer that using a new hash algorithm with TLS 1.2 would
   overcome the limitations of TLS 1.2.  However, there is still a need
   within TLSTM to support new values as they are developed.

   This document updates the definition of SnmpTLSFingerprint to clarify
   that the one-octet identifier in the fingerprint algorithm uses the
   IANA SNMP-TLSTM HashAlgorithm Registry; this registry is consistent
   with the IANA TLS HashAlgorithm Registry for its initial values but
   can be extended as needed to support new hashing algorithms without
   implying that the new values can be used by TLS version 1.2.  This
   change allows the reuse of the existing fingerprint TEXTUAL-
   CONVENTION and minimizes the impact to [RFC6353].

   A "Y" in the "Recommended" column indicates that the registered value
   has been recommended through a formal Standards Action.  Not all
   parameters defined in Standards Track documents are necessarily
   marked as "Recommended".

   An "N" in the "Recommended" column 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 initial values for the SNMP-TLSTM HashAlgorithm Registry are
   defined below:

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            +=========+=============+=============+===========+
            |  Value  | Description | Recommended | Reference |
            +=========+=============+=============+===========+
            | 0       | none        | N           | [RFC5246] |
            +---------+-------------+-------------+-----------+
            | 1       | md5         | N           | [RFC5246] |
            +---------+-------------+-------------+-----------+
            | 2       | sha1        | N           | [RFC5246] |
            +---------+-------------+-------------+-----------+
            | 3       | sha224      | Y           | [RFC5246] |
            +---------+-------------+-------------+-----------+
            | 4       | sha256      | Y           | [RFC5246] |
            +---------+-------------+-------------+-----------+
            | 5       | sha384      | Y           | [RFC5246] |
            +---------+-------------+-------------+-----------+
            | 6       | sha512      | Y           | [RFC5246] |
            +---------+-------------+-------------+-----------+
            | 7       | reserved    |             | [RFC8447] |
            +---------+-------------+-------------+-----------+
            | 8       | intrinsic   | N           | [RFC8422] |
            +---------+-------------+-------------+-----------+
            | 9-223   | reserved    |             | [RFC8447] |
            +---------+-------------+-------------+-----------+
            | 224-255 | private     |             | [RFC5246] |
            +---------+-------------+-------------+-----------+

                    Table 1: SNMP-TLSTM Hash Algorithms

   Values 0 through 2 MUST NOT be used by implementations of this
   document but are listed for historical consistency.

2.2.  Security Level

   The RFC3411 architecture recognizes three levels of security:

   *  without authentication and without privacy (noAuthNoPriv)

   *  with authentication but without privacy (authNoPriv)

   *  with authentication and with privacy (authPriv)

   Cipher suites for (D)TLS 1.3 defined in [RFC8446] provide both
   authentication and privacy.  Cipher suites defined in [RFC9150] for
   (D)TLS 1.3 provide only authentication, without any privacy
   protection.  Implementations MAY choose to force (D)TLS 1.3 to only
   allow cipher suites that provide both authentication and privacy.

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2.3.  (D)TLS Version

   [RFC6353] states that TLSTM clients and servers MUST NOT request,
   offer, or use SSL 2.0.  [RFC8996] prohibits the use of (D)TLS
   versions prior to version 1.2.  TLSTM MUST only be used with (D)TLS
   version 1.2 and later.

3.  Additional Rules for TLS 1.3

   This document specifies additional rules and clarifications for the
   use of TLS 1.3.  These rules may additionally apply to future
   versions of TLS.

3.1.  Zero Round Trip Time Resumption (0-RTT)

   TLS 1.3 implementations for SNMP MUST NOT enable the 0-RTT mode of
   session resumption (either sending or accepting) and MUST NOT
   automatically resend 0-RTT data if it is rejected by the server.  The
   reason 0-RTT is disallowed is that there are no "safe" SNMP messages
   that if replayed will be guaranteed to cause no harm at a server
   side: all incoming notification or command responses are meant to be
   acted upon only once.  See Security considerations section for
   further details.

   TLS TM clients and servers MUST NOT request, offer, or use the 0-RTT
   mode of TLS 1.3.  [RFC8446] removed the renegotiation supported in
   TLS 1.2 [RFC5246]; for session resumption, it introduced a zero-RTT
   (0-RTT) mode, saving a round-trip at connection setup at the cost of
   increased risk of replay attacks (it is possible for servers to guard
   against this attack by keeping track of all the messages received).
   [RFC8446] requires a profile be written for any application that
   wants to use 0-RTT, specifying which messages are "safe to use" on
   this mode.  Within SNMP, there are no messages that are "safe to use"
   with this mode.

   Renegotiation of sessions is not supported as it is not supported by
   TLS 1.3.  If a future version of TLS supports renegotiation, this RFC
   should be updated to indicate whether there are any additional
   requirements related to its use.

3.2.  TLS cipher suites, extensions and protocol invariants

   [RFC8446] section 9 requires that, in the absence of application
   profiles, certain cipher suites, TLS extensions, and TLS protocol
   invariants are mandatory to implement.  This document does not
   specify an application profile, hence all the compliance requirements
   in [RFC8446] apply.

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4.  MIB Module Definition

   This module makes references to [RFC1123], RFC2578, RFC2579, RFC2580,
   RFC3411, RFC3413, [RFC5246], [RFC5280], [RFC5890], [RFC5952],
   [RFC5953], [RFC6353], and [STD58]

   SNMP-TLS-TM-MIB DEFINITIONS ::= BEGIN

   IMPORTS
       MODULE-IDENTITY, OBJECT-TYPE,
       OBJECT-IDENTITY, mib-2, snmpDomains,
       Counter32, Unsigned32, Gauge32, NOTIFICATION-TYPE
         FROM SNMPv2-SMI               -- RFC 2578 or any update thereof
       TEXTUAL-CONVENTION, TimeStamp, RowStatus, StorageType,
       AutonomousType
         FROM SNMPv2-TC                -- RFC 2579 or any update thereof
       MODULE-COMPLIANCE, OBJECT-GROUP, NOTIFICATION-GROUP
         FROM SNMPv2-CONF              -- RFC 2580 or any update thereof
       SnmpAdminString
         FROM SNMP-FRAMEWORK-MIB       -- RFC 3411 or any update thereof
       snmpTargetParamsName, snmpTargetAddrName
         FROM SNMP-TARGET-MIB          -- RFC 3413 or any update thereof
       ;

   snmpTlstmMIB MODULE-IDENTITY
       LAST-UPDATED "202303010000Z"

       ORGANIZATION "OPSA Working Group"
       CONTACT-INFO "WG-EMail:   opsawg@ietf.org
                  Mailing list subscription info:
                  https://www.ietf.org/mailman/listinfo/opsawg

                  Kenneth Vaughn
                  Trevilon LLC
                  1060 Hwy 107 South
                  Del Rio, TN 37727
                  United States
                  Phone: +1 571 331 5670
                  Email: kvaughn@trevilon.com"
       DESCRIPTION  "
           The TLS Transport Model MIB

           Copyright (c) 2010-2022 IETF Trust and the persons identified
           as authors of the code.  All rights reserved.

           Redistribution and use in source and binary forms, with or
           without modification, is permitted pursuant to, and subject
           to the license terms contained in, the Revised BSD License

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           set forth in Section 4.c of the IETF Trust's Legal Provisions
           Relating to IETF Documents
           (http://trustee.ietf.org/license-info).

           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 (RFC 2119) (RFC 8174)
           when, and only when, they appear in all capitals, as shown
           here."

           REVISION    "202303010000Z"
           DESCRIPTION "This version of this MIB module is part of
                       RFC XXXX; see the RFC itself for full legal
                       notices.  This version: [ Note to RFC Editor:
                       please replace the above XXXX with the RFC number
                       of this document ]
                       1. Updates the definition of SnmpTLSFingerprint
                          to clarify the registry used for the one-octet
                          hash algorithm identifier.
                       2. Capitalizes key words in conformance with
                          BCP 14
                       3. Replaces 'may not' with 'MUST NOT' to clarify
                          intent in several locations.
                       4. Replaces 'may not' with a clarification within
                          the definition of SnmpTLSAddress"

          REVISION     "201107190000Z"
          DESCRIPTION  "This version of this MIB module is part of
                        RFC 6353; see the RFC itself for full legal
                        notices.  The only change was to introduce
                        new wording to reflect require changes for
                        IDNA addresses in the SnmpTLSAddress TC."

          REVISION     "201005070000Z"
          DESCRIPTION  "This version of this MIB module is part of
                        RFC 5953; see the RFC itself for full legal
                        notices."
       ::= { mib-2 198 }

   -- ************************************************
   -- subtrees of the SNMP-TLS-TM-MIB
   -- ************************************************

   snmpTlstmNotifications OBJECT IDENTIFIER ::= { snmpTlstmMIB 0 }
   snmpTlstmIdentities    OBJECT IDENTIFIER ::= { snmpTlstmMIB 1 }
   snmpTlstmObjects       OBJECT IDENTIFIER ::= { snmpTlstmMIB 2 }
   snmpTlstmConformance   OBJECT IDENTIFIER ::= { snmpTlstmMIB 3 }

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   snmpTlstmHashAlgorithms OBJECT-IDENTITY
       STATUS        current
       DESCRIPTION
          "A node used to register hashing algorithm identifiers recorded
          in the IANA SNMP-TLSTM HashAlgorithm Registry."
       ::= { snmpTlstmMIB 4 }

   -- ************************************************
   -- snmpTlstmObjects - Objects
   -- ************************************************

   snmpTLSTCPDomain OBJECT-IDENTITY
       STATUS      current
       DESCRIPTION
           "The SNMP over TLS via TCP transport domain.  The
           corresponding transport address is of type SnmpTLSAddress.

           The securityName prefix to be associated with the
           snmpTLSTCPDomain is 'tls'.  This prefix MAY be used by
           security models or other components to identify which secure
           transport infrastructure authenticated a securityName."
       REFERENCE
         "RFC 2579: Textual Conventions for SMIv2"
       ::= { snmpDomains 8 }

   snmpDTLSUDPDomain OBJECT-IDENTITY
       STATUS      current
       DESCRIPTION
           "The SNMP over DTLS via UDP transport domain.  The
           corresponding transport address is of type SnmpTLSAddress.

           The securityName prefix to be associated with the
           snmpDTLSUDPDomain is 'dtls'.  This prefix MAY be used by
           security models or other components to identify which secure
           transport infrastructure authenticated a securityName."
       REFERENCE
         "RFC 2579: Textual Conventions for SMIv2"
       ::= { snmpDomains 9 }

   SnmpTLSAddress ::= TEXTUAL-CONVENTION
       DISPLAY-HINT "1a"
       STATUS       current
       DESCRIPTION
           "Represents an IPv4 address, an IPv6 address, or a
            US-ASCII-encoded hostname and port number.

           An IPv4 address MUST be in dotted decimal format followed by

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           a colon ':' (US-ASCII character 0x3A) and a decimal port
           number in US-ASCII.

           An IPv6 address MUST be a colon-separated format (as
           described in RFC 5952), surrounded by square brackets ('[',
           US-ASCII character 0x5B, and ']', US-ASCII character 0x5D),
           followed by a colon ':' (US-ASCII character 0x3A) and a
           decimal port number in US-ASCII.

           A hostname MUST be in US-ASCII (as per RFC 1123);
           internationalized hostnames MUST be encoded as A-labels as
           specified in  RFC 5890.  The hostname is followed by a
           colon ':' (US-ASCII character 0x3A) and a decimal port number
           in US-ASCII.  The name SHOULD be fully qualified whenever
           possible.

           Values of this textual convention are not guaranteed to be
           directly usable as transport layer addressing information,
           potentially requiring additional processing, such as run-time
           resolution.  As such, applications that write them MUST be
           prepared for handling errors if such values are not
           supported, or cannot be resolved (if resolution occurs at the
           time of the management operation).

           The DESCRIPTION clause of TransportAddress objects that may
           have SnmpTLSAddress values MUST fully describe how (and
           when) such names are to be resolved to IP addresses and vice
           versa.

           This textual convention SHOULD NOT be used directly in object
           definitions since it restricts addresses to a specific
           format.  However, if it is used, it MAY be used either on its
           own or in conjunction with TransportAddressType or
           TransportDomain as a pair.

           When this textual convention is used as a syntax of an index
           object, there may be issues with the limit of 128
           sub-identifiers specified in SMIv2 (STD 58).  It is
           RECOMMENDED that all MIB documents using this textual
           convention make explicit any limitations on index component
           lengths that management software MUST observe.  This MAY be
           done either by including SIZE constraints on the index
           components or by specifying applicable constraints in the
           conceptual row DESCRIPTION clause or in the surrounding
           documentation."
       REFERENCE
         "RFC 1123: Requirements for Internet Hosts - Application and
                    Support

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          RFC 5890: Internationalized Domain Names for Applications
                    (IDNA): Definitions and Document Framework
          RFC 5952: A Recommendation for IPv6 Address Text
                    Representation"
       SYNTAX       OCTET STRING (SIZE (1..255))

   SnmpTLSFingerprint ::= TEXTUAL-CONVENTION
       DISPLAY-HINT "1x:1x"
       STATUS       current
       DESCRIPTION
          "A fingerprint value that can be used to uniquely reference
          other data of potentially arbitrary length.

          An SnmpTLSFingerprint value is composed of a 1-octet hashing
          algorithm identifier followed by the fingerprint value.  The
          1-octet identifier value encoded is taken from IANA SNMP-TLSTM
          HashAlgorithm Registry. The remaining octets of the
          SnmpTLSFingerprint value are filled using the results of the
          hashing algorithm.

          Historically, the 1-octet hashing algorithm identifier was
          based on the IANA TLS HashAlgorithm Registry (RFC 5246);
          however, this registry is no longer in use for TLS 1.3
          and above and are not expected to have any new registrations
          added to it. To
          allow the fingerprint algorithm to support additional hashing
          algorithms that might be used by later versions of (D)TLS, the
          octet value encoded is now taken from IANA SNMP-TLSTM
          HashAlgorithm Registry. The initial values within this
          registry are identical to the values in the TLS HashAlgorithm
          registry but can be extended to support new hashing algorithms
          as needed.

          This TEXTUAL-CONVENTION allows for a zero-length (blank)
          SnmpTLSFingerprint value for use in tables where the
          fingerprint value MAY be optional.  MIB definitions or
          implementations MAY refuse to accept a zero-length value as
          appropriate."
       REFERENCE "https://www.iana.org/assignments/smi-numbers/
          smi-numbers.xhtml"
       SYNTAX OCTET STRING (SIZE (0..255))

   -- Identities for use in the snmpTlstmCertToTSNTable

   snmpTlstmCertToTSNMIdentities OBJECT IDENTIFIER
       ::= { snmpTlstmIdentities 1 }

   snmpTlstmCertSpecified OBJECT-IDENTITY

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       STATUS        current
       DESCRIPTION
          "Directly specifies the tmSecurityName to be used for this
          certificate.  The value of the tmSecurityName to use is
          specified in the snmpTlstmCertToTSNData column.  The
          snmpTlstmCertToTSNData column MUST contain a non-zero length
          SnmpAdminString compliant value or the mapping described in
          this row MUST be considered a failure."
       ::= { snmpTlstmCertToTSNMIdentities 1 }

   snmpTlstmCertSANRFC822Name OBJECT-IDENTITY
       STATUS        current
       DESCRIPTION
          "Maps a subjectAltName's rfc822Name to a tmSecurityName.  The
          local part of the rfc822Name is passed unaltered but the
          host-part of the name MUST be passed in lowercase.  This
          mapping results in a 1:1 correspondence between equivalent
          subjectAltName rfc822Name values and tmSecurityName values
          except that the host-part of the name MUST be passed in
          lowercase.

          Example rfc822Name Field:  FooBar@Example.COM is mapped to
          tmSecurityName: FooBar@example.com."
       ::= { snmpTlstmCertToTSNMIdentities 2 }

   snmpTlstmCertSANDNSName OBJECT-IDENTITY
       STATUS        current
       DESCRIPTION
          "Maps a subjectAltName's dNSName to a tmSecurityName after
          first converting it to all lowercase (RFC 5280 does not
          specify converting to lowercase, so this involves an extra
          step).  This mapping results in a 1:1 correspondence between
          subjectAltName dNSName values and the tmSecurityName values."
       REFERENCE "RFC 5280 - Internet X.509 Public Key Infrastructure
                            Certificate and Certificate Revocation List
                            (CRL) Profile."
       ::= { snmpTlstmCertToTSNMIdentities 3 }

   snmpTlstmCertSANIpAddress OBJECT-IDENTITY
       STATUS        current
       DESCRIPTION
          "Maps a subjectAltName's iPAddress to a tmSecurityName by
          transforming the binary encoded address as follows:

          1) for IPv4, the value is converted into a decimal-dotted quad
          address (e.g., '192.0.2.1').

          2) for IPv6 addresses, the value is converted into a 32-

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          character all lowercase hexadecimal string without any colon
          separators.

          This mapping results in a 1:1 correspondence between
          subjectAltName iPAddress values and the tmSecurityName values.

          The resulting length of an encoded IPv6 address is the maximum
          length supported by the View-Based Access Control Model
          (VACM).  Using both the Transport Security Model's support for
          transport prefixes (see the SNMP-TSM-MIB's
          snmpTsmConfigurationUsePrefix object for details) will result
          in securityName lengths that exceed what VACM can handle."
       ::= { snmpTlstmCertToTSNMIdentities 4 }

   snmpTlstmCertSANAny OBJECT-IDENTITY
       STATUS        current
       DESCRIPTION
          "Maps any of the following fields using the corresponding
          mapping algorithms:

           |------------+----------------------------|
           | Type       | Algorithm                  |
           |------------+----------------------------|
           | rfc822Name | snmpTlstmCertSANRFC822Name |
           | dNSName    | snmpTlstmCertSANDNSName    |
           | iPAddress  | snmpTlstmCertSANIpAddress  |
           |------------+----------------------------|

          The first matching subjectAltName value found in the
          certificate of the above types MUST be used when deriving the
          tmSecurityName.  The mapping algorithm specified in the
          'Algorithm' column MUST be used to derive the tmSecurityName.

          This mapping results in a 1:1 correspondence between
          subjectAltName values and tmSecurityName values.  The three
          sub-mapping algorithms produced by this combined algorithm
          cannot produce conflicting results between themselves."
       ::= { snmpTlstmCertToTSNMIdentities 5 }

   snmpTlstmCertCommonName OBJECT-IDENTITY
       STATUS        current
       DESCRIPTION
          "Maps a certificate's CommonName to a tmSecurityName after
          converting it to a UTF-8 encoding.  The usage of CommonNames
          is deprecated and users are encouraged to use subjectAltName
          mapping methods instead.  This mapping results in a 1:1
          correspondence between certificate CommonName values and
          tmSecurityName values."

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       ::= { snmpTlstmCertToTSNMIdentities 6 }

   -- The snmpTlstmSession Group

   snmpTlstmSession         OBJECT IDENTIFIER ::= { snmpTlstmObjects 1 }

   snmpTlstmSessionOpens  OBJECT-TYPE
       SYNTAX       Counter32
       MAX-ACCESS   read-only
       STATUS       current
       DESCRIPTION
          "The number of times an openSession() request has been
          executed as a (D)TLS client, regardless of whether it
          succeeded or failed."
       ::= { snmpTlstmSession 1 }

   snmpTlstmSessionClientCloses  OBJECT-TYPE
       SYNTAX       Counter32
       MAX-ACCESS   read-only
       STATUS       current
       DESCRIPTION
           "The number of times a closeSession() request has been
           executed as a (D)TLS client, regardless of whether it
           succeeded or failed."
       ::= { snmpTlstmSession 2 }

   snmpTlstmSessionOpenErrors  OBJECT-TYPE
       SYNTAX       Counter32
       MAX-ACCESS   read-only
       STATUS       current
       DESCRIPTION
           "The number of times an openSession() request failed to open
           a session as a (D)TLS client, for any reason."
       ::= { snmpTlstmSession 3 }

   snmpTlstmSessionAccepts  OBJECT-TYPE
       SYNTAX       Counter32
       MAX-ACCESS   read-only
       STATUS       current
       DESCRIPTION
          "The number of times a (D)TLS server has accepted a new
          connection from a client and has received at least one SNMP
          message through it."
       ::= { snmpTlstmSession 4 }

   snmpTlstmSessionServerCloses  OBJECT-TYPE
       SYNTAX       Counter32
       MAX-ACCESS   read-only

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       STATUS       current
       DESCRIPTION
           "The number of times a closeSession() request has been
           executed as a (D)TLS server, regardless of whether it
           succeeded or failed."
       ::= { snmpTlstmSession 5 }

   snmpTlstmSessionNoSessions  OBJECT-TYPE
       SYNTAX       Counter32
       MAX-ACCESS   read-only
       STATUS       current
       DESCRIPTION
           "The number of times an outgoing message was dropped because
           the session associated with the passed tmStateReference was
           no longer (or was never) available."
       ::= { snmpTlstmSession 6 }

   snmpTlstmSessionInvalidClientCertificates OBJECT-TYPE
       SYNTAX       Counter32
       MAX-ACCESS   read-only
       STATUS       current
       DESCRIPTION
           "The number of times an incoming session was not established
           on a (D)TLS server because the presented client certificate
           was invalid.  Reasons for invalidation include, but are not
           limited to, cryptographic validation failures or lack of a
           suitable mapping row in the snmpTlstmCertToTSNTable."
       ::= { snmpTlstmSession 7 }

   snmpTlstmSessionUnknownServerCertificate OBJECT-TYPE
       SYNTAX       Counter32
       MAX-ACCESS   read-only
       STATUS       current
       DESCRIPTION
           "The number of times an outgoing session was not established
            on a (D)TLS client because the server certificate presented
            by an SNMP over (D)TLS server was invalid because no
            configured fingerprint or Certification Authority (CA) was
            acceptable to validate it.
            This may result because there was no entry in the
            snmpTlstmAddrTable or because no path could be found to a
            known CA."
       ::= { snmpTlstmSession 8 }

   snmpTlstmSessionInvalidServerCertificates OBJECT-TYPE
       SYNTAX       Counter32
       MAX-ACCESS   read-only
       STATUS       current

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       DESCRIPTION
           "The number of times an outgoing session was not established
            on a (D)TLS client because the server certificate presented
            by an SNMP over (D)TLS server could not be validated even if
            the fingerprint or expected validation path was known.  That
            is, a cryptographic validation error occurred during
            certificate validation processing.

           Reasons for invalidation include, but are not
           limited to, cryptographic validation failures."
       ::= { snmpTlstmSession 9 }

   snmpTlstmSessionInvalidCaches OBJECT-TYPE
       SYNTAX       Counter32
       MAX-ACCESS   read-only
       STATUS       current
       DESCRIPTION
           "The number of outgoing messages dropped because the
           tmStateReference referred to an invalid cache."
       ::= { snmpTlstmSession 10 }

   -- Configuration Objects

   snmpTlstmConfig          OBJECT IDENTIFIER ::= { snmpTlstmObjects 2 }

   -- Certificate mapping

   snmpTlstmCertificateMapping OBJECT IDENTIFIER ::= {snmpTlstmConfig 1}

   snmpTlstmCertToTSNCount OBJECT-TYPE
       SYNTAX      Gauge32
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
           "A count of the number of entries in the
           snmpTlstmCertToTSNTable."
       ::= { snmpTlstmCertificateMapping 1 }

   snmpTlstmCertToTSNTableLastChanged OBJECT-TYPE
       SYNTAX      TimeStamp
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
           "The value of sysUpTime.0 when the snmpTlstmCertToTSNTable
           was last modified through any means, or 0 if it has not been
           modified since the command responder was started."
       ::= { snmpTlstmCertificateMapping 2 }

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   snmpTlstmCertToTSNTable OBJECT-TYPE
       SYNTAX      SEQUENCE OF SnmpTlstmCertToTSNEntry
       MAX-ACCESS  not-accessible
       STATUS      current
       DESCRIPTION
           "This table is used by a (D)TLS server to map the (D)TLS
           client's presented X.509 certificate to a tmSecurityName.

           On an incoming (D)TLS/SNMP connection, the client's presented
           certificate MUST either be validated based on an established
           trust anchor, or it MUST directly match a fingerprint in this
           table.  This table does not provide any mechanisms for
           configuring the trust anchors; the transfer of any needed
           trusted certificates for path validation is expected to occur
           through an out-of-band transfer.

           Once the certificate has been found acceptable (either by
           path validation or directly matching a fingerprint in this
           table), this table is consulted to determine the appropriate
           tmSecurityName to identify with the remote connection.  This
           is done by considering each active row from this table in
           prioritized order according to its snmpTlstmCertToTSNID
           value. Each row's snmpTlstmCertToTSNFingerprint value
           determines whether the row is a match for the incoming
           connection:

               1) If the row's snmpTlstmCertToTSNFingerprint value
                  identifies the presented certificate, then consider
                  the row as a successful match.

               2) If the row's snmpTlstmCertToTSNFingerprint value
                  identifies a locally held copy of a trusted CA
                  certificate and that CA certificate was used to
                  validate the path to the presented certificate, then
                  consider the row as a successful match.

           Once a matching row has been found, the
           snmpTlstmCertToTSNMapType value can be used to determine how
           the tmSecurityName to associate with the session should be
           determined.  See the snmpTlstmCertToTSNMapType column's
           DESCRIPTION for details on determining the tmSecurityName
           value.  If it is impossible to determine a tmSecurityName
           from the row's data combined with the data presented in the
           certificate, then additional rows MUST be searched looking
           for another potential match.  If a resulting tmSecurityName
           mapped from a given row is not compatible with the needed
           requirements of a tmSecurityName (e.g., VACM imposes a
           32-octet-maximum length and the certificate derived

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           securityName could be longer), then it MUST be considered an
           invalid match and additional rows MUST be searched looking
           for another potential match.

           If no matching and valid row can be found, the connection
           MUST be closed and SNMP messages MUST NOT be accepted over
           it.

           Missing values of snmpTlstmCertToTSNID are acceptable and
           implementations SHOULD continue to the next highest numbered
           row.  It is RECOMMENDED that administrators skip index values
           to leave room for the insertion of future rows (for example,
           use values of 10 and 20 when creating initial rows).

           Users are encouraged to make use of certificates with
           subjectAltName fields that can be used as tmSecurityNames so
           that a single root CA certificate can allow all child
           certificate's subjectAltName to map directly to a
           tmSecurityName via a 1:1 transformation.  However, this table
           is flexible to allow for situations where existing deployed
           certificate infrastructures do not provide adequate
           subjectAltName values for use as tmSecurityNames.
           Certificates MAY also be mapped to tmSecurityNames using the
           CommonName portion of the Subject field.  However, the usage
           of the CommonName field is deprecated and thus this usage is
           NOT RECOMMENDED.  Direct mapping from each individual
           certificate fingerprint to a tmSecurityName is also possible
           but requires one entry in the table per tmSecurityName and
           requires more management operations to completely configure a
           device."
       ::= { snmpTlstmCertificateMapping 3 }

   snmpTlstmCertToTSNEntry OBJECT-TYPE
       SYNTAX      SnmpTlstmCertToTSNEntry
       MAX-ACCESS  not-accessible
       STATUS      current
       DESCRIPTION
           "A row in the snmpTlstmCertToTSNTable that specifies a
           mapping for an incoming (D)TLS certificate to a
           tmSecurityName to use for a connection."
       INDEX   { snmpTlstmCertToTSNID }
       ::= { snmpTlstmCertToTSNTable 1 }

   SnmpTlstmCertToTSNEntry ::= SEQUENCE {
       snmpTlstmCertToTSNID           Unsigned32,
       snmpTlstmCertToTSNFingerprint  SnmpTLSFingerprint,
       snmpTlstmCertToTSNMapType      AutonomousType,
       snmpTlstmCertToTSNData         OCTET STRING,

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       snmpTlstmCertToTSNStorageType  StorageType,
       snmpTlstmCertToTSNRowStatus    RowStatus
   }

   snmpTlstmCertToTSNID OBJECT-TYPE
       SYNTAX      Unsigned32 (1..4294967295)
       MAX-ACCESS  not-accessible
       STATUS      current
       DESCRIPTION
           "A unique, prioritized index for the given entry.  Lower
           numbers indicate a higher priority."
       ::= { snmpTlstmCertToTSNEntry 1 }

   snmpTlstmCertToTSNFingerprint OBJECT-TYPE
       SYNTAX      SnmpTLSFingerprint (SIZE(1..255))
       MAX-ACCESS  read-create
       STATUS      current
       DESCRIPTION
           "A cryptographic hash of an X.509 certificate.  The results
           of a successful matching fingerprint to either the trusted CA
           in the certificate validation path or to the certificate
           itself is dictated by the snmpTlstmCertToTSNMapType column."
       ::= { snmpTlstmCertToTSNEntry 2 }

   snmpTlstmCertToTSNMapType OBJECT-TYPE
       SYNTAX      AutonomousType
       MAX-ACCESS  read-create
       STATUS      current
       DESCRIPTION
           "Specifies the mapping type for deriving a tmSecurityName
           from a certificate.  Details for mapping of a particular type
           SHALL be specified in the DESCRIPTION clause of the OBJECT-
           IDENTITY that describes the mapping.  If a mapping succeeds
           it will return a tmSecurityName for use by the TLSTM model
           and processing stops.

           If the resulting mapped value is not compatible with the
           needed requirements of a tmSecurityName (e.g., VACM imposes a
           32-octet-maximum length and the certificate derived
           securityName could be longer), then future rows MUST be
           searched for additional snmpTlstmCertToTSNFingerprint matches
           to look for a mapping that succeeds.

           Suitable values for assigning to this object that are defined
           within the SNMP-TLS-TM-MIB can be found in the
           snmpTlstmCertToTSNMIdentities portion of the MIB tree."
       DEFVAL { snmpTlstmCertSpecified }
       ::= { snmpTlstmCertToTSNEntry 3 }

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   snmpTlstmCertToTSNData OBJECT-TYPE
       SYNTAX      OCTET STRING (SIZE(0..1024))
       MAX-ACCESS  read-create
       STATUS      current
       DESCRIPTION
           "Auxiliary data used as optional configuration information
           for a given mapping specified by the
           snmpTlstmCertToTSNMapType column.  Only some mapping
           systems will make use of this column.  The value in this
           column MUST be ignored for any mapping type that does not
           require data present in this column."
       DEFVAL { "" }
       ::= { snmpTlstmCertToTSNEntry 4 }

   snmpTlstmCertToTSNStorageType OBJECT-TYPE
       SYNTAX       StorageType
       MAX-ACCESS   read-create
       STATUS       current
       DESCRIPTION
           "The storage type for this conceptual row.  Conceptual rows
           having the value 'permanent' need not allow write-access to
           any columnar objects in the row."
       DEFVAL      { nonVolatile }
       ::= { snmpTlstmCertToTSNEntry 5 }

   snmpTlstmCertToTSNRowStatus OBJECT-TYPE
       SYNTAX      RowStatus
       MAX-ACCESS  read-create
       STATUS      current
       DESCRIPTION
           "The status of this conceptual row.  This object MAY be used
           to create or remove rows from this table.

           To create a row in this table, an administrator MUST set this
           object to either createAndGo(4) or createAndWait(5).

           Until instances of all corresponding columns are
           appropriately configured, the value of the corresponding
           instance of the snmpTlstmParamsRowStatus column is
           notReady(3).

           In particular, a newly created row cannot be made active
           until the corresponding snmpTlstmCertToTSNFingerprint,
           snmpTlstmCertToTSNMapType, and snmpTlstmCertToTSNData columns
           have been set.

           The following objects MUST NOT be modified while the
           value of this object is active(1):

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               - snmpTlstmCertToTSNFingerprint
               - snmpTlstmCertToTSNMapType
               - snmpTlstmCertToTSNData
           An attempt to set these objects while the value of
           snmpTlstmParamsRowStatus is active(1) will result in
           an inconsistentValue error."
       ::= { snmpTlstmCertToTSNEntry 6 }

   -- Maps tmSecurityNames to certificates for use by the
   -- SNMP-TARGET-MIB

   snmpTlstmParamsCount OBJECT-TYPE
       SYNTAX      Gauge32
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
           "A count of the number of entries in the
           snmpTlstmParamsTable."
       ::= { snmpTlstmCertificateMapping 4 }

   snmpTlstmParamsTableLastChanged OBJECT-TYPE
       SYNTAX      TimeStamp
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
           "The value of sysUpTime.0 when the snmpTlstmParamsTable
           was last modified through any means, or 0 if it has not been
           modified since the command responder was started."
       ::= { snmpTlstmCertificateMapping 5 }

   snmpTlstmParamsTable OBJECT-TYPE
       SYNTAX      SEQUENCE OF SnmpTlstmParamsEntry
       MAX-ACCESS  not-accessible
       STATUS      current
       DESCRIPTION
           "This table is used by a (D)TLS client when a (D)TLS
           connection is being set up using an entry in the
           SNMP-TARGET-MIB.  It extends the SNMP-TARGET-MIB's
           snmpTargetParamsTable with a fingerprint of a certificate to
           use when establishing such a (D)TLS connection."
       ::= { snmpTlstmCertificateMapping 6 }

   snmpTlstmParamsEntry OBJECT-TYPE
       SYNTAX      SnmpTlstmParamsEntry
       MAX-ACCESS  not-accessible
       STATUS      current
       DESCRIPTION
           "A conceptual row containing a fingerprint hash of a locally

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           held certificate for a given snmpTargetParamsEntry.  The
           values in this row SHOULD be ignored if the connection that
           needs to be established, as indicated by the SNMP-TARGET-MIB
           infrastructure, is not a certificate and (D)TLS based
           connection.  The connection SHOULD NOT be established if the
           certificate fingerprint stored in this entry does not point
           to a valid locally held certificate or if it points to an
           unusable certificate (such as might happen when the
           certificate's expiration date has been reached)."
       INDEX    { IMPLIED snmpTargetParamsName }
       ::= { snmpTlstmParamsTable 1 }

   SnmpTlstmParamsEntry ::= SEQUENCE {
       snmpTlstmParamsClientFingerprint SnmpTLSFingerprint,
       snmpTlstmParamsStorageType       StorageType,
       snmpTlstmParamsRowStatus         RowStatus
   }

   snmpTlstmParamsClientFingerprint OBJECT-TYPE
       SYNTAX      SnmpTLSFingerprint
       MAX-ACCESS  read-create
       STATUS      current
       DESCRIPTION
           "This object stores the hash of the public portion of a
           locally held X.509 certificate.  The X.509 certificate, its
           public key, and the corresponding private key will be used
           when initiating a (D)TLS connection as a (D)TLS client."
       ::= { snmpTlstmParamsEntry 1 }

   snmpTlstmParamsStorageType OBJECT-TYPE
       SYNTAX       StorageType
       MAX-ACCESS   read-create
       STATUS       current
       DESCRIPTION
           "The storage type for this conceptual row.  Conceptual rows
           having the value 'permanent' need not allow write-access to
           any columnar objects in the row."
       DEFVAL      { nonVolatile }
       ::= { snmpTlstmParamsEntry 2 }

   snmpTlstmParamsRowStatus OBJECT-TYPE
       SYNTAX      RowStatus
       MAX-ACCESS  read-create
       STATUS      current
       DESCRIPTION
           "The status of this conceptual row.  This object MAY be used
           to create or remove rows from this table.

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           To create a row in this table, an administrator MUST set this
           object to either createAndGo(4) or createAndWait(5).

           Until instances of all corresponding columns are
           appropriately configured, the value of the corresponding
           instance of the snmpTlstmParamsRowStatus column is
           notReady(3).

           In particular, a newly created row cannot be made active
           until the corresponding snmpTlstmParamsClientFingerprint
           column has been set.

           The snmpTlstmParamsClientFingerprint object MUST NOT be
           modified while the value of this object is active(1).

           An attempt to set these objects while the value of
           snmpTlstmParamsRowStatus is active(1) will result in
           an inconsistentValue error."
       ::= { snmpTlstmParamsEntry 3 }

   snmpTlstmAddrCount OBJECT-TYPE
       SYNTAX      Gauge32
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
           "A count of the number of entries in the snmpTlstmAddrTable."
       ::= { snmpTlstmCertificateMapping 7 }

   snmpTlstmAddrTableLastChanged OBJECT-TYPE
       SYNTAX      TimeStamp
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
           "The value of sysUpTime.0 when the snmpTlstmAddrTable
           was last modified through any means, or 0 if it has not been
           modified since the command responder was started."
       ::= { snmpTlstmCertificateMapping 8 }

   snmpTlstmAddrTable OBJECT-TYPE
       SYNTAX      SEQUENCE OF SnmpTlstmAddrEntry
       MAX-ACCESS  not-accessible
       STATUS      current
       DESCRIPTION
           "This table is used by a (D)TLS client when a (D)TLS
           connection is being set up using an entry in the
           SNMP-TARGET-MIB.  It extends the SNMP-TARGET-MIB's

           snmpTargetAddrTable so that the client can verify that the

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           correct server has been reached.  This verification can use
           either a certificate fingerprint, or an identity
           authenticated via certification path validation.

           If there is an active row in this table corresponding to the
           entry in the SNMP-TARGET-MIB that was used to establish the
           connection, and the row's snmpTlstmAddrServerFingerprint
           column has non-empty value, then the server's presented
           certificate is compared with the
           snmpTlstmAddrServerFingerprint value (and the
           snmpTlstmAddrServerIdentity column is ignored).  If the
           fingerprint matches, the verification has succeeded.  If the
           fingerprint does not match, then the connection MUST be
           closed.

           If the server's presented certificate has passed
           certification path validation [RFC5280] to a configured
           trust anchor, and an active row exists with a zero-length
           snmpTlstmAddrServerFingerprint value, then the
           snmpTlstmAddrServerIdentity column contains the expected
           host name.  This expected host name is then compared against
           the server's certificate as follows:

             - Implementations MUST support matching the expected host
             name against a dNSName in the subjectAltName extension
             field and MAY support checking the name against the
             CommonName portion of the subject distinguished name.

             - The '*' (ASCII 0x2a) wildcard character is allowed in the
             dNSName of the subjectAltName extension (and in common
             name, if used to store the host name), but only as the
             left-most (least significant) DNS label in that value.
             This wildcard matches any left-most DNS label in the
             server name.  That is, the subject *.example.com matches
             the server names a.example.com and b.example.com, but does
             not match example.com or a.b.example.com.  Implementations
             MUST support wildcards in certificates as specified above,
             but MAY provide a configuration option to disable them.

             - If the locally configured name is an internationalized
             domain name, conforming implementations MUST convert it to
             the ASCII Compatible Encoding (ACE) format for performing
             comparisons, as specified in Section 7 of [RFC5280].

           If the expected host name fails these conditions then the
           connection MUST be closed.

           If there is no row in this table corresponding to the entry

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           in the SNMP-TARGET-MIB and the server can be authorized by
           another, implementation-dependent means, then the connection
           MAY still proceed."
       ::= { snmpTlstmCertificateMapping 9 }

   snmpTlstmAddrEntry OBJECT-TYPE
       SYNTAX      SnmpTlstmAddrEntry
       MAX-ACCESS  not-accessible
       STATUS      current
       DESCRIPTION
           "A conceptual row containing a copy of a certificate's
           fingerprint for a given snmpTargetAddrEntry.  The values in
           this row SHOULD be ignored if the connection that needs to be
           established, as indicated by the SNMP-TARGET-MIB
           infrastructure, is not a (D)TLS based connection.  If an
           snmpTlstmAddrEntry exists for a given snmpTargetAddrEntry,
           then the presented server certificate MUST match or the
           connection MUST NOT be established.  If a row in this table
           does not exist to match an snmpTargetAddrEntry row, then the
           connection SHOULD still proceed if some other certificate
           validation path algorithm (e.g., RFC 5280) can be used."
       INDEX    { IMPLIED snmpTargetAddrName }
       ::= { snmpTlstmAddrTable 1 }

   SnmpTlstmAddrEntry ::= SEQUENCE {
       snmpTlstmAddrServerFingerprint    SnmpTLSFingerprint,
       snmpTlstmAddrServerIdentity       SnmpAdminString,
       snmpTlstmAddrStorageType          StorageType,
       snmpTlstmAddrRowStatus            RowStatus
   }

   snmpTlstmAddrServerFingerprint OBJECT-TYPE
       SYNTAX      SnmpTLSFingerprint
       MAX-ACCESS  read-create
       STATUS      current
       DESCRIPTION
           "A cryptographic hash of a public X.509 certificate.  This
           object should store the hash of the public X.509 certificate
           that the remote server should present during the (D)TLS
           connection setup.  The fingerprint of the presented
           certificate and this hash value MUST match exactly, or the
           connection MUST NOT be established."
       DEFVAL { "" }
       ::= { snmpTlstmAddrEntry 1 }

   snmpTlstmAddrServerIdentity OBJECT-TYPE
       SYNTAX      SnmpAdminString
       MAX-ACCESS  read-create

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       STATUS      current
       DESCRIPTION
           "The reference identity to check against the identity
           presented by the remote system."
       DEFVAL { "" }
       ::= { snmpTlstmAddrEntry 2 }

   snmpTlstmAddrStorageType OBJECT-TYPE
       SYNTAX       StorageType
       MAX-ACCESS   read-create
       STATUS       current
       DESCRIPTION
           "The storage type for this conceptual row.  Conceptual rows
           having the value 'permanent' need not allow write-access to
           any columnar objects in the row."
       DEFVAL      { nonVolatile }
       ::= { snmpTlstmAddrEntry 3 }

   snmpTlstmAddrRowStatus OBJECT-TYPE
       SYNTAX      RowStatus
       MAX-ACCESS  read-create
       STATUS      current
       DESCRIPTION
           "The status of this conceptual row.  This object may be used
           to create or remove rows from this table.

           To create a row in this table, an administrator MUST set this
           object to either createAndGo(4) or createAndWait(5).

           Until instances of all corresponding columns are
           appropriately configured, the value of the
           corresponding instance of the snmpTlstmAddrRowStatus
           column is notReady(3).

           In particular, a newly created row cannot be made active
           until the corresponding snmpTlstmAddrServerFingerprint column
           has been set.

           Rows MUST NOT be active if the snmpTlstmAddrServerFingerprint
           column is blank and the snmpTlstmAddrServerIdentity is set to
           '*' since this would insecurely accept any presented
           certificate.

           The snmpTlstmAddrServerFingerprint object MUST NOT be
           modified while the value of this object is active(1).

           An attempt to set these objects while the value of
           snmpTlstmAddrRowStatus is active(1) will result in

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           an inconsistentValue error."
       ::= { snmpTlstmAddrEntry 4 }

   -- ************************************************
   --  snmpTlstmNotifications - Notifications Information
   -- ************************************************

   snmpTlstmServerCertificateUnknown NOTIFICATION-TYPE
       OBJECTS { snmpTlstmSessionUnknownServerCertificate }
       STATUS  current
       DESCRIPTION
           "Notification that the server certificate presented by an
           SNMP over (D)TLS server was invalid because no configured
           fingerprint or CA was acceptable to validate it.  This may
           be because there was no entry in the snmpTlstmAddrTable or
           because no path could be found to known Certification
           Authority.

           To avoid notification loops, this notification MUST NOT be
           sent to servers that themselves have triggered the
           notification."
       ::= { snmpTlstmNotifications 1 }

   snmpTlstmServerInvalidCertificate NOTIFICATION-TYPE
       OBJECTS { snmpTlstmAddrServerFingerprint,
                 snmpTlstmSessionInvalidServerCertificates}
       STATUS  current
       DESCRIPTION
           "Notification that the server certificate presented by an
           SNMP over (D)TLS server could not be validated even if the
           fingerprint or expected validation path was known.  That is,
           a cryptographic validation error occurred during certificate
           validation processing.

           To avoid notification loops, this notification MUST NOT be
           sent to servers that themselves have triggered the
           notification."
       ::= { snmpTlstmNotifications 2 }

   -- ************************************************
   -- snmpTlstmCompliances - Conformance Information
   -- ************************************************

   snmpTlstmCompliances OBJECT IDENTIFIER ::= { snmpTlstmConformance 1 }

   snmpTlstmGroups OBJECT IDENTIFIER ::= { snmpTlstmConformance 2 }

   -- ************************************************

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   -- Compliance statements
   -- ************************************************

   snmpTlstmCompliance MODULE-COMPLIANCE
       STATUS      current
       DESCRIPTION
           "The compliance statement for SNMP engines that support the
           SNMP-TLS-TM-MIB"
       MODULE
           MANDATORY-GROUPS { snmpTlstmStatsGroup,
                              snmpTlstmIncomingGroup,
                              snmpTlstmOutgoingGroup,
                              snmpTlstmNotificationGroup }
       ::= { snmpTlstmCompliances 1 }

   -- ************************************************
   -- Units of conformance
   -- ************************************************
   snmpTlstmStatsGroup OBJECT-GROUP
       OBJECTS {
           snmpTlstmSessionOpens,
           snmpTlstmSessionClientCloses,
           snmpTlstmSessionOpenErrors,
           snmpTlstmSessionAccepts,
           snmpTlstmSessionServerCloses,
           snmpTlstmSessionNoSessions,
           snmpTlstmSessionInvalidClientCertificates,
           snmpTlstmSessionUnknownServerCertificate,
           snmpTlstmSessionInvalidServerCertificates,
           snmpTlstmSessionInvalidCaches
       }
       STATUS      current
       DESCRIPTION
           "A collection of objects for maintaining
           statistical information of an SNMP engine that
           implements the SNMP TLS Transport Model."
       ::= { snmpTlstmGroups 1 }

   snmpTlstmIncomingGroup OBJECT-GROUP
       OBJECTS {
           snmpTlstmCertToTSNCount,
           snmpTlstmCertToTSNTableLastChanged,
           snmpTlstmCertToTSNFingerprint,
           snmpTlstmCertToTSNMapType,
           snmpTlstmCertToTSNData,
           snmpTlstmCertToTSNStorageType,
           snmpTlstmCertToTSNRowStatus
       }

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       STATUS      current
       DESCRIPTION
           "A collection of objects for maintaining
           incoming connection certificate mappings to
           tmSecurityNames of an SNMP engine that implements the
           SNMP TLS Transport Model."
       ::= { snmpTlstmGroups 2 }

   snmpTlstmOutgoingGroup OBJECT-GROUP
       OBJECTS {
           snmpTlstmParamsCount,
           snmpTlstmParamsTableLastChanged,
           snmpTlstmParamsClientFingerprint,
           snmpTlstmParamsStorageType,
           snmpTlstmParamsRowStatus,
           snmpTlstmAddrCount,
           snmpTlstmAddrTableLastChanged,
           snmpTlstmAddrServerFingerprint,
           snmpTlstmAddrServerIdentity,
           snmpTlstmAddrStorageType,
           snmpTlstmAddrRowStatus
       }
       STATUS      current
       DESCRIPTION
           "A collection of objects for maintaining
           outgoing connection certificates to use when opening
           connections as a result of SNMP-TARGET-MIB settings."
       ::= { snmpTlstmGroups 3 }

   snmpTlstmNotificationGroup NOTIFICATION-GROUP
       NOTIFICATIONS {
           snmpTlstmServerCertificateUnknown,
           snmpTlstmServerInvalidCertificate
       }
       STATUS current
       DESCRIPTION
           "Notifications"
       ::= { snmpTlstmGroups 4 }

   END

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5.  Security Considerations

   This document updates a transport model that permits SNMP to utilize
   (D)TLS security services.  The security threats and how the TLS
   transport model mitigates these threats are covered throughout this
   document and in [RFC6353].  Security considerations for TLS are
   described in Section 10 and Appendix E of TLS 1.3 [RFC8446].
   Security considerations for DTLS are described in Section 11 of DTLS
   1.3 [RFC9147].

   Implementations should consider the latest recommendations on the use
   of (DTLS), such as that documented in [RFC9325].

   SNMP versions prior to SNMPv3 did not include adequate security.
   Even if the network itself is secure (for example, by using IPsec),
   there is no control as to who on the secure network is allowed to
   access and GET/SET (read/change/create/delete) the objects in this
   MIB module.

   It is RECOMMENDED that only SNMPv3 messages using the Transport
   Security Model (TSM) or another secure-transport aware security model
   be sent over the TLSTM transport.

6.  IANA Considerations

   IANA is asked to create a new registry called the SNMP-TLSTM
   HashAlgorithm Registry in the Structure of Management Information
   (SMI) Numbers (MIB Module Registrations) Group and to update the
   proposed URL reference in the above MIB (listed as
   "https://www.iana.org/assignments/smi-numbers/smi-numbers.xhtml"
   under SnmpTLSFingerprint), if needed, to accurately reflect its
   location.  The description of this registry should be:
   iso.org.dod.internet.mgmt.mib-2.snmpTlstmMIB.snmpTlstmHashAlgorithms
   (1.3.6.1.2.1.198.4)

   The registry should have the following fields: value, description,
   recommended, and reference.  The range of values is zero to 255, with
   initial assignments shown in Section 2.1.  The "recommended" column
   indicates "Y" for hashing algorithms that are standards track and are
   deemed to be acceptable for widely applicable current use and "N" for
   hashing algorithms that reflect meanings that are not recommended
   (e.g., they do not provide sufficient security for modern systems,
   they are not standards track, they have limited applicability).  A
   blank field indicates that no recommendation is made (e.g., because
   the value is reserved or left for private use).

   This registry is expected to be updated infrequently and, as such,
   its values are limited to one octet.

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   The policy for updates is Expert Review.  The expert should consult
   the Security Area, e.g. via the mailing list of the TLS WG (the
   initial values of this registry are taken from an existing TLS
   Registry so the TLS WG would seem the best fit for this).

   While future additions to the IANA TLS HashAlgorithm Registry are not
   expected, any future addition to the IANA TLS HashAlgorithm Registry
   MUST be consistent with the values assigned in the IANA SNMP-TLSTM
   HashAlgorithm Registry.

7.  Acknowledgements

   This document is based on [RFC6353].  This document was reviewed by
   the following people who helped provide useful comments: Michaela
   Vanderveen, Joe Clarke, Jurgen Schonwalder, and Tom Petch.

8.  References

8.1.  Normative References

   [RFC1123]  Braden, R., Ed., "Requirements for Internet Hosts -
              Application and Support", STD 3, RFC 1123,
              DOI 10.17487/RFC1123, October 1989,
              <https://www.rfc-editor.org/info/rfc1123>.

   [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>.

   [RFC5280]  Cooper, D., Santesson, S., Farrell, S., Boeyen, S.,
              Housley, R., and W. Polk, "Internet X.509 Public Key
              Infrastructure Certificate and Certificate Revocation List
              (CRL) Profile", RFC 5280, DOI 10.17487/RFC5280, May 2008,
              <https://www.rfc-editor.org/info/rfc5280>.

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

   [RFC5952]  Kawamura, S. and M. Kawashima, "A Recommendation for IPv6
              Address Text Representation", RFC 5952,
              DOI 10.17487/RFC5952, August 2010,
              <https://www.rfc-editor.org/info/rfc5952>.

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   [RFC6353]  Hardaker, W., "Transport Layer Security (TLS) Transport
              Model for the Simple Network Management Protocol (SNMP)",
              STD 78, RFC 6353, DOI 10.17487/RFC6353, July 2011,
              <https://www.rfc-editor.org/info/rfc6353>.

   [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>.

   [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/info/rfc8446>.

   [STD58]    McCloghrie, K., Ed., Perkins, D., Ed., and J.
              Schoenwaelder, Ed., "Structure of Management Information
              Version 2 (SMIv2)", STD 58, RFC 2578, April 1999.

              McCloghrie, K., Ed., Perkins, D., Ed., and J.
              Schoenwaelder, Ed., "Textual Conventions for SMIv2",
              STD 58, RFC 2579, April 1999.

              McCloghrie, K., Ed., Perkins, D., Ed., and J.
              Schoenwaelder, Ed., "Conformance Statements for SMIv2",
              STD 58, RFC 2580, April 1999.

   [STD62]    Harrington, D., Presuhn, R., and B. Wijnen, "An
              Architecture for Describing Simple Network Management
              Protocol (SNMP) Management Frameworks", STD 62, RFC 3411,
              December 2002.

              Case, J., Harrington, D., Presuhn, R., and B. Wijnen,
              "Message Processing and Dispatching for the Simple Network
              Management Protocol (SNMP)", STD 62, RFC 3412, December
              2002.

              Levi, D., Meyer, P., and B. Stewart, "Simple Network
              Management Protocol (SNMP) Applications", STD 62,
              RFC 3413, December 2002.

              Blumenthal, U. and B. Wijnen, "User-based Security Model
              (USM) for version 3 of the Simple Network Management
              Protocol (SNMPv3)", STD 62, RFC 3414, December 2002.

              Wijnen, B., Presuhn, R., and K. McCloghrie, "View-based
              Access Control Model (VACM) for the Simple Network
              Management Protocol (SNMP)", STD 62, RFC 3415, December
              2002.

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              Presuhn, R., Ed., "Version 2 of the Protocol Operations
              for the Simple Network Management Protocol (SNMP)",
              STD 62, RFC 3416, December 2002.

              Presuhn, R., Ed., "Transport Mappings for the Simple
              Network Management Protocol (SNMP)", STD 62, RFC 3417,
              December 2002.

              Presuhn, R., Ed., "Management Information Base (MIB) for
              the Simple Network Management Protocol (SNMP)", STD 62,
              RFC 3418, December 2002.

8.2.  Informative References

   [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>.

   [RFC5953]  Hardaker, W., "Transport Layer Security (TLS) Transport
              Model for the Simple Network Management Protocol (SNMP)",
              RFC 5953, DOI 10.17487/RFC5953, August 2010,
              <https://www.rfc-editor.org/info/rfc5953>.

   [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/info/rfc8422>.

   [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/info/rfc8447>.

   [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/info/rfc8996>.

   [RFC9147]  Rescorla, E., Tschofenig, H., and N. Modadugu, "The
              Datagram Transport Layer Security (DTLS) Protocol Version
              1.3", RFC 9147, DOI 10.17487/RFC9147, April 2022,
              <https://www.rfc-editor.org/info/rfc9147>.

   [RFC9150]  Cam-Winget, N. and J. Visoky, "TLS 1.3 Authentication and
              Integrity-Only Cipher Suites", RFC 9150,
              DOI 10.17487/RFC9150, April 2022,
              <https://www.rfc-editor.org/info/rfc9150>.

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   [RFC9325]  Sheffer, Y., Saint-Andre, P., and T. Fossati,
              "Recommendations for Secure Use of Transport Layer
              Security (TLS) and Datagram Transport Layer Security
              (DTLS)", BCP 195, RFC 9325, DOI 10.17487/RFC9325, November
              2022, <https://www.rfc-editor.org/info/rfc9325>.

Author's Address

   Kenneth Vaughn (editor)
   Trevilon LLC
   1060 Highway 107 South
   Del Rio, TN 37727
   United States of America
   Phone: +1 571 331 5670
   Email: kvaughn@trevilon.com

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