Internet DRAFT - draft-vaughn-tlstm-update
draft-vaughn-tlstm-update
Internet Engineering Task Force K. Vaughn, Ed.
Internet-Draft Trevilon LLC
Updates: 6353 (if approved) 27 June 2021
Intended status: Standards Track
Expires: 29 December 2021
Transport Layer Security Verion 1.3 (TLS 1.3) Transport Model for the
Simple Network Management Protocol Version 3 (SNMPv3)
draft-vaughn-tlstm-update-01
Abstract
This document updates the TLS Transport Model (TLSTM), as defined in
[RFC6353], to support Transport Layer Security Version 1.3 (TLS)
[RFC8446] and Datagram Transport Layer Security Version 1.3 (DTLS)
[I-D.ietf-tls-dtls13], which are jointly known as "(D)TLS". This
document may be applicable to future versions of SNMP and (D)TLS.
This document updates the SNMP-TLS-TM-MIB as defined in [RFC6353].
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 29 December 2021.
Copyright Notice
Copyright (c) 2021 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
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extracted from this document must include Simplified BSD License text
as described in Section 4.e of the Trust Legal Provisions and are
provided without warranty as described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Conventions . . . . . . . . . . . . . . . . . . . . . . . 3
2. Changes from RFC 6353 . . . . . . . . . . . . . . . . . . . . 4
2.1. TLSTM Fingerprint . . . . . . . . . . . . . . . . . . . . 4
2.2. Security Level . . . . . . . . . . . . . . . . . . . . . 5
2.3. TLS Version . . . . . . . . . . . . . . . . . . . . . . . 5
2.4. SNMP Version . . . . . . . . . . . . . . . . . . . . . . 5
2.5. Common Name . . . . . . . . . . . . . . . . . . . . . . . 6
3. Additional Rules for TLS 1.3 . . . . . . . . . . . . . . . . 6
3.1. Zero Round Trip Time Resumption (0-RTT) . . . . . . . . . 6
3.2. TLS ciphersuites, extensions and protocol invariants . . 6
4. MIB Module Definition . . . . . . . . . . . . . . . . . . . . 6
5. Security Considerations . . . . . . . . . . . . . . . . . . . 37
5.1. MIB Module Security . . . . . . . . . . . . . . . . . . . 37
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 38
7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 39
8. References . . . . . . . . . . . . . . . . . . . . . . . . . 39
8.1. Normative References . . . . . . . . . . . . . . . . . . 39
8.2. Informative References . . . . . . . . . . . . . . . . . 40
Appendix A. Target and Notification Configuration Example . . . 41
A.1. Configuring a Notification Originator . . . . . . . . . . 41
A.2. Configuring TLSTM to Utilize a Simple Derivation of
tmSecurityName . . . . . . . . . . . . . . . . . . . . . 42
A.3. Configuring TLSTM to Utilize Table-Driven Certificate
Mapping . . . . . . . . . . . . . . . . . . . . . . . . . 42
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 43
1. Introduction
This document updates the fingerprint algorithm defined by [RFC6353]
to support the ciphersuites used by Transport Layer Security Version
1.3 (TLS) and Datagram Transport Layer Security Version 1.3 (DTLS),
which are jointly known as "(D)TLS". The update also incorporates
other less critical updates. Although the title and text of this
document specifically reference SNMPv3 and (D)TLS 1.3, this document
may be applicable to future versions of these protocols.
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1.1. Conventions
Within this document the terms "TLS", "DTLS", "(D)TLS", "SNMP", and
"TLSTM" mean "TLS 1.3", "DTLS 1.3", "TLS 1.3 and/or DTLS 1.3",
"SMNPv3", and "TLSTM 1.3", respectively. These version numbers are
only used when the text needs to emphasize version numbers, such as
within the title. When this document refers to any other version of
these protocols, it always explicitly states the version intended.
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
consistent with the IESG decision to not require the SNMPv3
terminology be modified to match the usage of other non-SNMP
specifications when SNMPv3 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.
While TLS frequently refers to a user, the terminology preferred in
RFC3411 and in this memo is "principal". A principal is the "who" on
whose behalf services are provided or processing takes place. A
principal can be, among other things, an individual acting in a
particular role; a set of individuals, with each acting in a
particular role; an application or a set of applications, or a
combination of these within an administrative domain.
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Throughout this document, the term "session" is used to refer to a
secure association between two TLS Transport Models 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 User-Based Security Model (USM) (RFC3414) is a mandatory-to-
implement Security Model in [STD62]. The USM derives the
securityName and securityLevel from the SNMP message received, even
when the message was received over a secure transport. It is
RECOMMENDED that deployments that support the TLSTM disable the USM,
if it has been implemented.
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
[RFC2119].
2. Changes from RFC 6353
This document updates [RFC6353]. The changes from [RFC6353] are
defined in the following clauses.
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 thereby breaking the algorithm defined in [RFC6353]. The
update to the SNMP-TLS-TM-MIB, as defined in Section 4, deprecates
the original fingerprint TEXTUAL-CONVENTION and replaces it with a
new TEXTUAL-CONVENTION.
The change also required an update to several objects within the
tables defined within the SNMP-TLS-TM-MIB; further these objects are
referernced by other (e.g., RowStatus) objects in a manner that
requires deprecating and replacing the tables in their entirety.
Thus, while the number of objects deprecated and replaced is
significant the semantics of the changes are minor.
References to the older objects within [RFC6353] are applicable to
the replacement objects. The newer objects are identified with names
similar to those used in the original MIB but with a "13" inserted to
reference TLS 1.3.
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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)
With (D)TLS 1.3, authentication and privacy are always provided.
Hence, all exchanges conforming to the rules of this document will
include authentication and privacy, regardless of the security level
requested.
// This is consistent with what was prescribed in RFC6353, where a
// TLS Transport Model is expected to provide for outgoing
// connections with a security level at least that of the requested
// security level.
2.3. TLS Version
[RFC6353] stated that TLSTM clients and servers MUST NOT request,
offer, or use SSL 2.0. This document extends this statement such
that TLSTM clients and servers MUST NOT request, offer, or use SSL
3.0, (D)TLSv 1.0, (D)TLS v1.1. See Appendix D.5 of [RFC8446] for
further details. For backward compatibility issues with older TLS
versions, see Appendix D of [RFC8446].
An implementation that supports these older protocols is not
considered conformant to the TLSTM while the older protocols are
enabled.
2.4. SNMP Version
[RFC6353] stated that using a non-transport-aware Security Model with
a secure Transport Model was not recommended. This document tightens
this statement such that TLSTM clients and servers MUST NOT request,
offer, or use SNMPv1 or SNMPv2c message processing described in
[RFC3584], or the User-based Security Model of SNMPv3.
An implementation that supports these older protocols is not
considered conformant to the TLSTM while the older protocols are
enabled.
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2.5. Common Name
[RFC6353] stated that the use of a certificate's CommonName is
deprecated and users were encouraged to use the subjectAltName. This
document tightens this statement such that TLSTM clients and servers
MUST NOT use the CommonName.
3. Additional Rules for TLS 1.3
This document specifies additional rules and clarifications for the
use of TLS 1.3.
3.1. Zero Round Trip Time Resumption (0-RTT)
TLS 1.3 implementations for SNMPv3 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" 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. The reason 0-RTT is disallowed here is that there are no
"safe" SNMPv3 messages that if replayed will be sure to cause no harm
at a server side: all incoming notification or command responses have
consequences and are to be acted upon only once.
Renegotiation of sessions is not supported as it is not supported by
TLS 1.3.
3.2. TLS ciphersuites, 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 of the compliance
requirements in [RFC8446] apply.
4. MIB Module Definition
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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 "202106220000Z"
ORGANIZATION "ISMS Working Group"
CONTACT-INFO "Kenneth Vaughn
Trevilon LLC
6606 FM 1488 RD, STE 503
Magnolia, TX 77354
USA
kvaughn@trevilon.com
DESCRIPTION "
The TLS Transport Model MIB
Copyright (c) 2010-2021 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 Simplified BSD License
set forth in Section 4.c of the IETF Trust's Legal Provisions
Relating to IETF Documents
(http://trustee.ietf.org/license-info)."
REVISION "202106220000Z"
DESCRIPTION "This version of this MIB module is part of
RFC XXXX; see the RFC itself for full legal
notices. This version updated the MIB to
support (D)TLS 1.3."
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."
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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 }
-- ************************************************
-- 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 deprecated
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 a
colon ':' (US-ASCII character 0x3A) and a decimal port number
in US-ASCII.
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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 is always in US-ASCII (as per RFC 1123);
internationalized hostnames are 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 may not be directly usable
as transport-layer addressing information, and may require
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
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 deprecated
DESCRIPTION
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"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
octet value encoded is taken from the IANA TLS HashAlgorithm
Registry (RFC 5246). The remaining octets are filled using the
results of the hashing algorithm.
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.
This textual convention was deprecated because TLS 1.3 uses a
2-octet cipher suite identifier rather than a 1-octet hashing
algorithm identifier."
REFERENCE "RFC 5246: The Transport Layer
Security (TLS) Protocol Version 1.2
http://www.iana.org/assignments/tls-parameters/
"
SYNTAX OCTET STRING (SIZE (0..255))
SnmpTLS13Fingerprint ::= 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 SnmpTLS13Fingerprint value is composed of a 2-octet cipher
suite identifier followed by the fingerprint value. The
octet value encoded is taken from the IANA TLS Cipher Suites
Registry(RFC 8446). The remaining octets are filled using the
results of the hashing algorithm, up to the first 253 octets.
This TEXTUAL-CONVENTION allows for a zero-length (blank)
SnmpTLS13Fingerprint 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 "RFC 8446: The Transport Layer
Security (TLS) Protocol Version 1.3
http://www.iana.org/assignments/tls-parameters/
"
SYNTAX OCTET STRING (SIZE (0..255))
-- Identities for use in the snmpTlstmCertToTSNTable and
-- snmpTlstmCertToTSN13Table
snmpTlstmCertToTSNMIdentities OBJECT IDENTIFIER
::= { snmpTlstmIdentities 1 }
snmpTlstmCertSpecified OBJECT-IDENTITY
STATUS current
DESCRIPTION "Directly specifies the tmSecurityName to be used for
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this certificate. The value of the tmSecurityName
to use is specified in the snmpTlstmCertToTSN13Data
column. The snmpTlstmCertToTSN13Data 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-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
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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 deprecated
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."
::= { 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
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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
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 }
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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 or the
snmpTlstmCertToTSN13Table."
::= { 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 snmpTlstmAddr13Table) or because no
path could be found to a known CA."
::= { snmpTlstmSession 8 }
snmpTlstmSessionInvalidServerCertificates 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 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 }
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-- Configuration Objects
snmpTlstmConfig OBJECT IDENTIFIER ::= {snmpTlstmObjects 2}
-- Certificate mapping
snmpTlstmCertificateMapping OBJECT IDENTIFIER ::= {snmpTlstmConfig 1}
snmpTlstmCertToTSNCount OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS deprecated
DESCRIPTION
"A count of the number of entries in the
snmpTlstmCertToTSNTable."
::= { snmpTlstmCertificateMapping 1 }
snmpTlstmCertToTSNTableLastChanged OBJECT-TYPE
SYNTAX TimeStamp
MAX-ACCESS read-only
STATUS deprecated
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 }
snmpTlstmCertToTSNTable OBJECT-TYPE
SYNTAX SEQUENCE OF SnmpTlstmCertToTSNEntry
MAX-ACCESS not-accessible
STATUS deprecated
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
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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
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.
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.
This table and its associated objects were deprecated because
the fingerprint format changed to support TLS 1.3. By
deprecating (and creating an updated) table, rather than just
the fingerprint object, an implementation is able to support
both the original TLS and new TLS 1.3 tables while forcing some
agents to only use TLS 1.3."
::= { snmpTlstmCertificateMapping 3 }
snmpTlstmCertToTSNEntry OBJECT-TYPE
SYNTAX SnmpTlstmCertToTSNEntry
MAX-ACCESS not-accessible
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STATUS deprecated
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,
snmpTlstmCertToTSNStorageType StorageType,
snmpTlstmCertToTSNRowStatus RowStatus
}
snmpTlstmCertToTSNID OBJECT-TYPE
SYNTAX Unsigned32 (1..4294967295)
MAX-ACCESS not-accessible
STATUS deprecated
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 deprecated
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.
This object was deprecated because TLS 1.3 uses a 2-octet
cipher suite identifier rather than a 1-octet hashing algorithm
identifier."
::= { snmpTlstmCertToTSNEntry 2 }
snmpTlstmCertToTSNMapType OBJECT-TYPE
SYNTAX AutonomousType
MAX-ACCESS read-create
STATUS deprecated
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
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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 }
snmpTlstmCertToTSNData OBJECT-TYPE
SYNTAX OCTET STRING (SIZE(0..1024))
MAX-ACCESS read-create
STATUS deprecated
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 deprecated
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 deprecated
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
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have been set.
The following objects may not be modified while the
value of this object is active(1):
- 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 SNMP-TARGET-MIB
snmpTlstmParamsCount OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS deprecated
DESCRIPTION
"A count of the number of entries in the snmpTlstmParamsTable."
::= { snmpTlstmCertificateMapping 4 }
snmpTlstmParamsTableLastChanged OBJECT-TYPE
SYNTAX TimeStamp
MAX-ACCESS read-only
STATUS deprecated
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 deprecated
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 deprecated
DESCRIPTION
"A conceptual row containing a fingerprint hash of a locally
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 TLS based
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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 deprecated
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 TLS connection as a TLS client."
::= { snmpTlstmParamsEntry 1 }
snmpTlstmParamsStorageType OBJECT-TYPE
SYNTAX StorageType
MAX-ACCESS read-create
STATUS deprecated
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 deprecated
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 snmpTlstmParamsClientFingerprint column has
been set.
The snmpTlstmParamsClientFingerprint object may not be modified
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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 }
mpTlstmAddrCount OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS deprecated
DESCRIPTION
"A count of the number of entries in the snmpTlstmAddrTable."
::= { snmpTlstmCertificateMapping 7 }
snmpTlstmAddrTableLastChanged OBJECT-TYPE
SYNTAX TimeStamp
MAX-ACCESS read-only
STATUS deprecated
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 deprecated
DESCRIPTION
"This table is used by a TLS client when a 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
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
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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
- The '*' (ASCII 0x2a) wildcard character is allowed in the
dNSName of the subjectAltName extension, 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
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 deprecated
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 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,
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snmpTlstmAddrRowStatus RowStatus
}
snmpTlstmAddrServerFingerprint OBJECT-TYPE
SYNTAX SnmpTLSFingerprint
MAX-ACCESS read-create
STATUS deprecated
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 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
STATUS deprecated
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 deprecated
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 deprecated
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
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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 may 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
an inconsistentValue error."
::= { snmpTlstmAddrEntry 4 }
snmpTlstmCertToTSN13Count OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"A count of the number of entries in the
snmpTlstmCertToTSN13Table."
::= { snmpTlstmCertificateMapping 10 }
snmpTlstmCertToTSN13TableLastChanged OBJECT-TYPE
SYNTAX TimeStamp
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The value of sysUpTime.0 when the snmpTlstmCertToTSN13Table
was last modified through any means, or 0 if it has not been
modified since the command responder was started."
::= { snmpTlstmCertificateMapping 11 }
snmpTlstmCertToTSN13Table OBJECT-TYPE
SYNTAX SEQUENCE OF SnmpTlstmCertToTSN13Entry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"This table is used by a TLS 1.3 server to map the TLS 1.3
client's presented X.509 certificate to a tmSecurityName.
On an incoming 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
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is done by considering each active row from this table in
prioritized order according to its snmpTlstmCertToTSN13ID
value. Each row's snmpTlstmCertToTSN13Fingerprint value
determines whether the row is a match for the incoming
connection:
1) If the row's snmpTlstmCertToTSN13Fingerprint value
identifies the presented certificate, then consider the
row as a successful match.
2) If the row's snmpTlstmCertToTSN13Fingerprint 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
snmpTlstmCertToTSN13MapType value can be used to determine how
the tmSecurityName to associate with the session should be
determined. See the snmpTlstmCertToTSN13MapType 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
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 snmpTlstmCertToTSN13ID 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.
Direct mapping from each individual certificate fingerprint to
a tmSecurityName is possible but requires one entry in the
table per tmSecurityName and requires more management
operations to completely configure a device."
::= { snmpTlstmCertificateMapping 12 }
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snmpTlstmCertToTSN13Entry OBJECT-TYPE
SYNTAX SnmpTlstmCertToTSN13Entry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"A row in the snmpTlstmCertToTSN13Table that specifies a
mapping for an incoming TLS certificate to a tmSecurityName
to use for a connection."
INDEX { snmpTlstmCertToTSN13ID }
::= { snmpTlstmCertToTSN13Table 1 }
SnmpTlstmCertToTSN13Entry ::= SEQUENCE {
snmpTlstmCertToTSN13ID Unsigned32,
snmpTlstmCertToTSN13Fingerprint SnmpTLS13Fingerprint,
snmpTlstmCertToTSN13MapType AutonomousType,
snmpTlstmCertToTSN13Data OCTET STRING,
snmpTlstmCertToTSN13StorageType StorageType,
snmpTlstmCertToTSN13RowStatus RowStatus
}
snmpTlstmCertToTSN13ID 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."
::= { snmpTlstmCertToTSN13Entry 1 }
snmpTlstmCertToTSN13Fingerprint OBJECT-TYPE
SYNTAX SnmpTLS13Fingerprint (SIZE(2..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 snmpTlstmCertToTSN13MapType column."
::= { snmpTlstmCertToTSN13Entry 2 }
snmpTlstmCertToTSN13MapType 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
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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 snmpTlstmCertToTSN13Fingerprint 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 }
::= { snmpTlstmCertToTSN13Entry 3 }
snmpTlstmCertToTSN13Data 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 snmpTlstmCertToTSN13MapType
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 { "" }
::= { snmpTlstmCertToTSN13Entry 4 }
snmpTlstmCertToTSN13StorageType 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 }
::= { snmpTlstmCertToTSN13Entry 5 }
snmpTlstmCertToTSN13RowStatus 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
snmpTlstmParams13RowStatus column is notReady(3).
In particular, a newly created row cannot be made active until
the corresponding snmpTlstmCertToTSN13Fingerprint,
snmpTlstmCertToTSN13MapType, and snmpTlstmCertToTSN13Data
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columns have been set.
The following objects may not be modified while the
value of this object is active(1):
- snmpTlstmCertToTSN13Fingerprint
- snmpTlstmCertToTSN13MapType
- snmpTlstmCertToTSN13Data
An attempt to set these objects while the value of
snmpTlstmParams13RowStatus is active(1) will result in
an inconsistentValue error."
::= { snmpTlstmCertToTSN13Entry 6 }
snmpTlstmParams13Count OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"A count of the number of entries in the
snmpTlstmParams13Table."
::= { snmpTlstmCertificateMapping 13 }
snmpTlstmParams13TableLastChanged OBJECT-TYPE
SYNTAX TimeStamp
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The value of sysUpTime.0 when the snmpTlstmParams13Table
was last modified through any means, or 0 if it has not been
modified since the command responder was started."
::= { snmpTlstmCertificateMapping 14 }
snmpTlstmParams13Table OBJECT-TYPE
SYNTAX SEQUENCE OF SnmpTlstmParams13Entry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"This table is used by a TLS client when a TLS
connection is being set up using an entry in the
SNMP-TARGET-MIB. It extends the SNMP-TARGET-MIB's
snmpTargetParams13Table with a fingerprint of a certificate to
use when establishing such a TLS connection."
::= { snmpTlstmCertificateMapping 15 }
snmpTlstmParams13Entry OBJECT-TYPE
SYNTAX SnmpTlstmParams13Entry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"A conceptual row containing a fingerprint hash of a locally
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 TLS based
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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 }
::= { snmpTlstmParams13Table 1 }
SnmpTlstmParams13Entry ::= SEQUENCE {
snmpTlstmParams13ClientFingerprint SnmpTLS13Fingerprint,
snmpTlstmParams13StorageType StorageType,
snmpTlstmParams13RowStatus RowStatus
}
snmpTlstmParams13ClientFingerprint OBJECT-TYPE
SYNTAX SnmpTLS13Fingerprint
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 TLS connection as a TLS client."
::= { snmpTlstmParams13Entry 1 }
snmpTlstmParams13StorageType 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 }
::= { snmpTlstmParams13Entry 2 }
snmpTlstmParams13RowStatus 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
snmpTlstmParams13RowStatus column is notReady(3).
In particular, a newly created row cannot be made active until
the corresponding snmpTlstmParams13ClientFingerprint column has
been set.
The snmpTlstmParams13ClientFingerprint object may not be
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modified while the value of this object is active(1).
An attempt to set these objects while the value of
snmpTlstmParams13RowStatus is active(1) will result in
an inconsistentValue error."
::= { snmpTlstmParams13Entry 3 }
snmpTlstmAddr13Count OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"A count of the number of entries in the snmpTlstmAddr13Table."
::= { snmpTlstmCertificateMapping 16 }
snmpTlstmAddr13TableLastChanged OBJECT-TYPE
SYNTAX TimeStamp
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The value of sysUpTime.0 when the snmpTlstmAddr13Table
was last modified through any means, or 0 if it has not been
modified since the command responder was started."
::= { snmpTlstmCertificateMapping 17 }
snmpTlstmAddr13Table OBJECT-TYPE
SYNTAX SEQUENCE OF SnmpTlstmAddr13Entry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"This table is used by a TLS client when a 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
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 snmpTlstmAddr13ServerFingerprint
column has non-empty value, then the server's presented
certificate is compared with the
snmpTlstmAddr13ServerFingerprint value (and the
snmpTlstmAddr13ServerIdentity 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
snmpTlstmAddr13ServerFingerprint value, then the
snmpTlstmAddr13ServerIdentity column contains the expected
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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.
- The '*' (ASCII 0x2a) wildcard character is allowed in the
dNSName of the subjectAltName extension, 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
in the SNMP-TARGET-MIB and the server can be authorized by
another, implementation-dependent means, then the connection
MAY still proceed."
::= { snmpTlstmCertificateMapping 18 }
snmpTlstmAddr13Entry OBJECT-TYPE
SYNTAX SnmpTlstmAddr13Entry
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 TLS based connection. If an
snmpTlstmAddr13Entry 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 }
::= { snmpTlstmAddr13Table 1 }
SnmpTlstmAddr13Entry ::= SEQUENCE {
snmpTlstmAddr13ServerFingerprint SnmpTLS13Fingerprint,
snmpTlstmAddr13ServerIdentity SnmpAdminString,
snmpTlstmAddr13StorageType StorageType,
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snmpTlstmAddr13RowStatus RowStatus
}
snmpTlstmAddr13ServerFingerprint OBJECT-TYPE
SYNTAX SnmpTLS13Fingerprint
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 TLS
connection setup. The fingerprint of the presented
certificate and this hash value MUST match exactly or the
connection MUST NOT be established."
DEFVAL { "" }
::= { snmpTlstmAddr13Entry 1 }
snmpTlstmAddr13ServerIdentity OBJECT-TYPE
SYNTAX SnmpAdminString
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The reference identity to check against the identity
presented by the remote system."
DEFVAL { "" }
::= { snmpTlstmAddr13Entry 2 }
snmpTlstmAddr13StorageType 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 }
::= { snmpTlstmAddr13Entry 3 }
snmpTlstmAddr13RowStatus 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 snmpTlstmAddr13RowStatus
column is notReady(3).
In particular, a newly created row cannot be made active until
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the corresponding snmpTlstmAddr13ServerFingerprint column has
been set.
Rows MUST NOT be active if the snmpTlstmAddr13ServerFingerprint
column is blank and the snmpTlstmAddr13ServerIdentity is set to
'*' since this would insecurely accept any presented
certificate.
The snmpTlstmAddr13ServerFingerprint object may not be modified
while the value of this object is active(1).
An attempt to set these objects while the value of
snmpTlstmAddr13RowStatus is active(1) will result in
an inconsistentValue error."
::= { snmpTlstmAddr13Entry 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
snmpTlstmAddr13Table) 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 deprecated
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 }
snmpTlstmServerInvalidCertificate13 NOTIFICATION-TYPE
OBJECTS { snmpTlstmAddr13ServerFingerprint,
snmpTlstmSessionInvalidServerCertificates}
STATUS current
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DESCRIPTION
"Notification that the server certificate presented by an SNMP
over 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 3 }
-- ************************************************
-- snmpTlstmCompliances - Conformance Information
-- ************************************************
snmpTlstmCompliances OBJECT IDENTIFIER ::= { snmpTlstmConformance 1 }
snmpTlstmGroups OBJECT IDENTIFIER ::= { snmpTlstmConformance 2 }
-- ************************************************
-- Compliance statements
-- ************************************************
snmpTlstmCompliance MODULE-COMPLIANCE
STATUS deprecated
DESCRIPTION
"The compliance statement for SNMP engines that support the
SNMP-TLS-TM-MIB"
MODULE
MANDATORY-GROUPS { snmpTlstmStatsGroup,
snmpTlstmIncomingGroup,
snmpTlstmOutgoingGroup,
snmpTlstmNotificationGroup }
::= { snmpTlstmCompliances 1 }
snmpTlstmCompliance13 MODULE-COMPLIANCE
STATUS current
DESCRIPTION
"The compliance statement for SNMP engines that support the
SNMP-TLS-TM-MIB"
MODULE
MANDATORY-GROUPS { snmpTlstmStatsGroup,
snmpTlstmIncoming13Group,
snmpTlstmOutgoing13Group,
snmpTlstmNotification13Group }
::= { snmpTlstmCompliances 2 }
-- ************************************************
-- Units of conformance
-- ************************************************
snmpTlstmStatsGroup OBJECT-GROUP
OBJECTS {
snmpTlstmSessionOpens,
snmpTlstmSessionClientCloses,
snmpTlstmSessionOpenErrors,
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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
}
STATUS deprecated
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 deprecated
DESCRIPTION
"A collection of objects for maintaining
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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 deprecated
DESCRIPTION
"Notifications"
::= { snmpTlstmGroups 4 }
snmpTlstmIncoming13Group OBJECT-GROUP
OBJECTS {
snmpTlstmCertToTSN13Count,
snmpTlstmCertToTSN13TableLastChanged,
snmpTlstmCertToTSN13Fingerprint,
snmpTlstmCertToTSN13MapType,
snmpTlstmCertToTSN13Data,
snmpTlstmCertToTSN13StorageType,
snmpTlstmCertToTSN13RowStatus
}
STATUS current
DESCRIPTION
"A collection of objects for maintaining
incoming connection certificate mappings to
tmSecurityNames of an SNMP engine that implements the
SNMP TLS 1.3 Transport Model."
::= { snmpTlstmGroups 5 }
snmpTlstmOutgoing13Group OBJECT-GROUP
OBJECTS {
snmpTlstmParams13Count,
snmpTlstmParams13TableLastChanged,
snmpTlstmParams13ClientFingerprint,
snmpTlstmParams13StorageType,
snmpTlstmParams13RowStatus,
snmpTlstmAddr13Count,
snmpTlstmAddr13TableLastChanged,
snmpTlstmAddr13ServerFingerprint,
snmpTlstmAddr13ServerIdentity,
snmpTlstmAddr13StorageType,
snmpTlstmAddr13RowStatus
}
STATUS current
DESCRIPTION
"A collection of objects for maintaining
outgoing connection certificates to use when opening
TLS 1.3 connections as a result of SNMP-TARGET-MIB settings."
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::= { snmpTlstmGroups 6 }
snmpTlstmNotification13Group NOTIFICATION-GROUP
NOTIFICATIONS {
snmpTlstmServerCertificateUnknown,
snmpTlstmServerInvalidCertificate13
}
STATUS current
DESCRIPTION
"Notifications for the SNMP TLS 1.3 Transport Model"
::= { snmpTlstmGroups 7 }
END
5. Security Considerations
This document updates a transport model that permits SNMP to utilize
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].
5.1. MIB Module Security
There are a number of management objects defined in this MIB module
with a MAX-ACCESS clause of read-write and/or read-create. Such
objects might be considered sensitive or vulnerable in some network
environments. The support for SET operations in a non-secure
environment without proper protection can have a negative effect on
network operations. These are the tables and objects and their
sensitivity/vulnerability:
* The snmpTlstmParams13Table can be used to change the outgoing
X.509 certificate used to establish a TLS connection.
Modifications to objects in this table need to be adequately
authenticated since modifying the values in this table will have
profound impacts to the security of outbound connections from the
device. Since knowledge of authorization rules and certificate
usage mechanisms might be considered sensitive, protection from
disclosure of the SNMP traffic via encryption is automatically
acheived via TLS 1.3.
* The snmpTlstmAddr13Table can be used to change the expectations of
the certificates presented by a remote TLS server. Modifications
to objects in this table need to be adequately authenticated since
modifying the values in this table will have profound impacts to
the security of outbound connections from the device. Since
knowledge of authorization rules and certificate usage mechanisms
might be considered sensitive, protection from disclosure of the
SNMP traffic via encryption is automatically acheived via TLS 1.3.
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* The snmpTlstmCertToTSN13Table is used to specify the mapping of
incoming X.509 certificates to tmSecurityNames, which eventually
get mapped to an SNMPv3 securityName. Modifications to objects in
this table need to be adequately authenticated since modifying the
values in this table will have profound impacts to the security of
incoming connections to the device. Since knowledge of
authorization rules and certificate usage mechanisms might be
considered sensitive, protection from disclosure of the SNMP
traffic via encryption is automatically acheived via TLS 1.3.
When this table contains a significant number of rows it might
affect the system performance when accepting new TLS connections.
Some of the readable objects in this MIB module (i.e., objects with a
MAX-ACCESS other than not-accessible) might be considered sensitive
or vulnerable in some network environments. It is thus important to
control even GET and/or NOTIFY access to these objects and encrypt
the values of these objects when sending them over the network via
SNMP. These are the tables and objects and their sensitivity/
vulnerability:
* This MIB contains a collection of counters that monitor the TLS
connections being established with a device. Since knowledge of
connection and certificate usage mechanisms might be considered
sensitive, protection from disclosure of the SNMP traffic via
encryption is automatically acheived via TLS 1.3.
SNMP versions prior to SNMPv3 did not include adequate security.
Even if the network itself is secure (for example, by using IPsec),
even then, 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.
As defined in Section 2.4, TLSTM clients and servers MUST NOT
request, offer, or use SNMPv1 or SNMPv2c message processing described
in [RFC3584], or the User-based Security Model of SNMPv3. Instead,
it is RECOMMENDED to deploy SNMPv3 and to enable cryptographic
security. It is then a customer/operator responsibility to ensure
that the SNMP entity giving access to an instance of this MIB module
is properly configured to give access to the objects only to those
principals (users) that have legitimate rights to indeed GET or SET
(change/create/delete) them.
6. IANA Considerations
This document has no IANA actions beyond those performed as a part of
[RFC6353].
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7. Acknowledgements
Acknowledgements This document is based on [RFC6353]. This document
was reviewed by the following people who helped provide useful
comments: Michaela Vanderveen.
8. References
8.1. Normative References
[I-D.ietf-tls-dtls13]
Rescorla, E., Tschofenig, H., and N. Modadugu, "The
Datagram Transport Layer Security (DTLS) Protocol Version
1.3", Work in Progress, Internet-Draft, draft-ietf-tls-
dtls13-43, 30 April 2021,
<https://datatracker.ietf.org/doc/html/draft-ietf-tls-
dtls13-43>.
[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>.
[RFC3584] Frye, R., Levi, D., Routhier, S., and B. Wijnen,
"Coexistence between Version 1, Version 2, and Version 3
of the Internet-standard Network Management Framework",
BCP 74, RFC 3584, DOI 10.17487/RFC3584, August 2003,
<https://www.rfc-editor.org/info/rfc3584>.
[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>.
[RFC5591] Harrington, D. and W. Hardaker, "Transport Security Model
for the Simple Network Management Protocol (SNMP)",
STD 78, RFC 5591, DOI 10.17487/RFC5591, June 2009,
<https://www.rfc-editor.org/info/rfc5591>.
[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>.
[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>.
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[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.
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>.
[STD58] McCloghrie, K., Ed., Perkins, D., Ed., and J.
Schoenwaelder, Ed., "Structure of Management Information
Version 2 (SMIv2)", STD 58, RFC 2578, April 1999.
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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.
Appendix A. Target and Notification Configuration Example
The following sections describe example configuration for the SNMP-
TLS-TM-MIB, the SNMP-TARGET-MIB, the NOTIFICATION-MIB, and the SNMP-
VIEW-BASED-ACM-MIB.
A.1. Configuring a Notification Originator
The following row adds the "Joe Cool" user to the "administrators"
group:
vacmSecurityModel = 4 (TSM)
vacmSecurityName = "Joe Cool"
vacmGroupName = "administrators"
vacmSecurityToGroupStorageType = 3 (nonVolatile)
vacmSecurityToGroupStatus = 4 (createAndGo)
The following row configures the snmpTlstmAddr13Table to use
certificate path validation and to require the remote notification
receiver to present a certificate for the "server.example.org"
identity.
snmpTargetAddrName = "toNRAddr"
snmpTlstmAddr13ServerFingerprint = ""
snmpTlstmAddr13ServerIdentity = "server.example.org"
snmpTlstmAddr13StorageType = 3 (nonVolatile)
snmpTlstmAddr13RowStatus = 4 (createAndGo)
The following row configures the snmpTargetAddrTable to send
notifications using TLS/TCP to the snmptls-trap port at 192.0.2.1:
snmpTargetAddrName = "toNRAddr"
snmpTargetAddrTDomain = snmpTLSTCPDomain
snmpTargetAddrTAddress = "192.0.2.1:10162"
snmpTargetAddrTimeout = 1500
snmpTargetAddrRetryCount = 3
snmpTargetAddrTagList = "toNRTag"
snmpTargetAddrParams = "toNR" (MUST match below)
snmpTargetAddrStorageType = 3 (nonVolatile)
snmpTargetAddrRowStatus = 4 (createAndGo)
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The following row configures the snmpTargetParamsTable to send the
notifications to "Joe Cool", using authPriv SNMPv3 notifications
through the TransportSecurityModel [[RFC5591]]:
snmpTargetParamsName = "toNR" (MUST match above)
snmpTargetParamsMPModel = 3 (SNMPv3)
snmpTargetParamsSecurityModel = 4 (TransportSecurityModel)
snmpTargetParamsSecurityName = "Joe Cool"
snmpTargetParamsSecurityLevel = 3 (authPriv)
snmpTargetParamsStorageType = 3 (nonVolatile)
snmpTargetParamsRowStatus = 4 (createAndGo)
A.2. Configuring TLSTM to Utilize a Simple Derivation of tmSecurityName
The following row configures the snmpTlstmCertToTSN13Table to map a
validated client certificate, referenced by the client's public X.509
hash fingerprint, to a tmSecurityName using the subjectAltName
component of the certificate.
snmpTlstmCertToTSN13ID = 1
(chosen by ordering preference)
snmpTlstmCertToTSN13Fingerprint = HASH (appropriate fingerprint)
snmpTlstmCertToTSN13MapType = snmpTlstmCertSANAny
snmpTlstmCertToTSN13Data = "" (not used)
snmpTlstmCertToTSN13StorageType = 3 (nonVolatile)
snmpTlstmCertToTSN13RowStatus = 4 (createAndGo)
This type of configuration should only be used when the naming
conventions of the (possibly multiple) Certification Authorities are
well understood, so two different principals cannot inadvertently be
identified by the same derived tmSecurityName.
A.3. Configuring TLSTM to Utilize Table-Driven Certificate Mapping
The following row configures the snmpTlstmCertToTSN13Table to map a
validated client certificate, referenced by the client's public X.509
hash fingerprint, to the directly specified tmSecurityName of "Joe
Cool".
snmpTlstmCertToTSN13ID = 2
(chosen by ordering preference)
snmpTlstmCertToTSN13Fingerprint = HASH (appropriate fingerprint)
snmpTlstmCertToTSN13MapType = snmpTlstmCertSpecified
snmpTlstmCertToTSN13SecurityName = "Joe Cool"
snmpTlstmCertToTSN13StorageType = 3 (nonVolatile)
snmpTlstmCertToTSN13RowStatus = 4 (createAndGo)
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Author's Address
Kenneth Vaughn (editor)
Trevilon LLC
6606 FM 1488 RD
Suite 148-503
Magnolia, TX 77354
United States of America
Phone: +1 571 331 5670
Email: kvaughn@trevilon.com
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