draft-ietf-isms-dtls-tm-14.txt   rfc5953.txt 
ISMS W. Hardaker Internet Engineering Task Force (IETF) W. Hardaker
Internet-Draft Sparta, Inc. Request for Comments: 5953 SPARTA, Inc.
Intended status: Standards Track May 7, 2010 Category: Standards Track August 2010
Expires: November 8, 2010 ISSN: 2070-1721
Transport Layer Security (TLS) Transport Model for the Simple Network Transport Layer Security (TLS) Transport Model
Management Protocol (SNMP) for the Simple Network Management Protocol (SNMP)
draft-ietf-isms-dtls-tm-14.txt
Abstract Abstract
This document describes a Transport Model for the Simple Network This document describes a Transport Model for the Simple Network
Management Protocol (SNMP), that uses either the Transport Layer Management Protocol (SNMP), that uses either the Transport Layer
Security protocol or the Datagram Transport Layer Security (DTLS) Security protocol or the Datagram Transport Layer Security (DTLS)
protocol. The TLS and DTLS protocols provide authentication and protocol. The TLS and DTLS protocols provide authentication and
privacy services for SNMP applications. This document describes how privacy services for SNMP applications. This document describes how
the TLS Transport Model (TLSTM) implements the needed features of a the TLS Transport Model (TLSTM) implements the needed features of a
SNMP Transport Subsystem to make this protection possible in an SNMP Transport Subsystem to make this protection possible in an
interoperable way. interoperable way.
This transport model is designed to meet the security and operational This Transport Model is designed to meet the security and operational
needs of network administrators. It supports sending of SNMP needs of network administrators. It supports the sending of SNMP
messages over TLS/TCP and DTLS/UDP. The TLS mode can make use of messages over TLS/TCP and DTLS/UDP. The TLS mode can make use of
TCP's improved support for larger packet sizes and the DTLS mode TCP's improved support for larger packet sizes and the DTLS mode
provides potentially superior operation in environments where a provides potentially superior operation in environments where a
connectionless (e.g. UDP) transport is preferred. Both TLS and DTLS connectionless (e.g., UDP) transport is preferred. Both TLS and DTLS
integrate well into existing public keying infrastructures. integrate well into existing public keying infrastructures.
This document also defines a portion of the Management Information This document also defines a portion of the Management Information
Base (MIB) for use with network management protocols. In particular Base (MIB) for use with network management protocols. In particular,
it defines objects for managing the TLS Transport Model for SNMP. it defines objects for managing the TLS Transport Model for SNMP.
Status of this Memo Status of This Memo
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Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 5 1. Introduction ....................................................4
1.1. Conventions . . . . . . . . . . . . . . . . . . . . . . . 8 1.1. Conventions ................................................7
2. The Transport Layer Security Protocol . . . . . . . . . . . . 9 2. The Transport Layer Security Protocol ...........................8
3. How the TLSTM fits into the Transport Subsystem . . . . . . . 9 3. How the TLSTM Fits into the Transport Subsystem .................8
3.1. Security Capabilities of this Model . . . . . . . . . . . 11 3.1. Security Capabilities of this Model .......................10
3.1.1. Threats . . . . . . . . . . . . . . . . . . . . . . . 11 3.1.1. Threats ............................................10
3.1.2. Message Protection . . . . . . . . . . . . . . . . . . 12 3.1.2. Message Protection .................................11
3.1.3. (D)TLS Connections . . . . . . . . . . . . . . . . . . 13 3.1.3. (D)TLS Connections .................................12
3.2. Security Parameter Passing . . . . . . . . . . . . . . . . 14 3.2. Security Parameter Passing ................................13
3.3. Notifications and Proxy . . . . . . . . . . . . . . . . . 14 3.3. Notifications and Proxy ...................................13
4. Elements of the Model . . . . . . . . . . . . . . . . . . . . 15 4. Elements of the Model ..........................................14
4.1. X.509 Certificates . . . . . . . . . . . . . . . . . . . . 15 4.1. X.509 Certificates ........................................14
4.1.1. Provisioning for the Certificate . . . . . . . . . . . 15 4.1.1. Provisioning for the Certificate ...................14
4.2. (D)TLS Usage . . . . . . . . . . . . . . . . . . . . . . . 17 4.2. (D)TLS Usage ..............................................16
4.3. SNMP Services . . . . . . . . . . . . . . . . . . . . . . 17 4.3. SNMP Services .............................................17
4.3.1. SNMP Services for an Outgoing Message . . . . . . . . 18 4.3.1. SNMP Services for an Outgoing Message ..............17
4.3.2. SNMP Services for an Incoming Message . . . . . . . . 19 4.3.2. SNMP Services for an Incoming Message ..............18
4.4. Cached Information and References . . . . . . . . . . . . 19 4.4. Cached Information and References .........................19
4.4.1. TLS Transport Model Cached Information . . . . . . . . 20 4.4.1. TLS Transport Model Cached Information .............19
4.4.1.1. tmSecurityName . . . . . . . . . . . . . . . . . . 20 4.4.1.1. tmSecurityName ............................19
4.4.1.2. tmSessionID . . . . . . . . . . . . . . . . . . . 20 4.4.1.2. tmSessionID ...............................20
4.4.1.3. Session State . . . . . . . . . . . . . . . . . . 21 4.4.1.3. Session State .............................20
5. Elements of Procedure . . . . . . . . . . . . . . . . . . . . 21 5. Elements of Procedure ..........................................20
5.1. Procedures for an Incoming Message . . . . . . . . . . . . 21 5.1. Procedures for an Incoming Message ........................20
5.1.1. DTLS over UDP Processing for Incoming Messages . . . . 22 5.1.1. DTLS over UDP Processing for Incoming Messages .....21
5.1.2. Transport Processing for Incoming SNMP Messages . . . 23 5.1.2. Transport Processing for Incoming SNMP Messages ....22
5.2. Procedures for an Outgoing SNMP Message . . . . . . . . . 24 5.2. Procedures for an Outgoing SNMP Message ...................24
5.3. Establishing or Accepting a Session . . . . . . . . . . . 26 5.3. Establishing or Accepting a Session .......................25
5.3.1. Establishing a Session as a Client . . . . . . . . . . 26 5.3.1. Establishing a Session as a Client .................25
5.3.2. Accepting a Session as a Server . . . . . . . . . . . 28 5.3.2. Accepting a Session as a Server ....................27
5.4. Closing a Session . . . . . . . . . . . . . . . . . . . . 29 5.4. Closing a Session .........................................28
6. MIB Module Overview . . . . . . . . . . . . . . . . . . . . . 29 6. MIB Module Overview ............................................29
6.1. Structure of the MIB Module . . . . . . . . . . . . . . . 30 6.1. Structure of the MIB Module ...............................29
6.2. Textual Conventions . . . . . . . . . . . . . . . . . . . 30 6.2. Textual Conventions .......................................29
6.3. Statistical Counters . . . . . . . . . . . . . . . . . . . 30 6.3. Statistical Counters ......................................29
6.4. Configuration Tables . . . . . . . . . . . . . . . . . . . 30 6.4. Configuration Tables ......................................29
6.4.1. Notifications . . . . . . . . . . . . . . . . . . . . 30 6.4.1. Notifications ......................................30
6.5. Relationship to Other MIB Modules . . . . . . . . . . . . 30 6.5. Relationship to Other MIB Modules .........................30
6.5.1. MIB Modules Required for IMPORTS . . . . . . . . . . . 31 6.5.1. MIB Modules Required for IMPORTS ...................30
7. MIB Module Definition . . . . . . . . . . . . . . . . . . . . 31 7. MIB Module Definition ..........................................30
8. Operational Considerations . . . . . . . . . . . . . . . . . . 54 8. Operational Considerations .....................................53
8.1. Sessions . . . . . . . . . . . . . . . . . . . . . . . . . 54 8.1. Sessions ..................................................53
8.2. Notification Receiver Credential Selection . . . . . . . . 54 8.2. Notification Receiver Credential Selection ................54
8.3. contextEngineID Discovery . . . . . . . . . . . . . . . . 55 8.3. contextEngineID Discovery .................................54
8.4. Transport Considerations . . . . . . . . . . . . . . . . . 55 8.4. Transport Considerations ..................................55
9. Security Considerations . . . . . . . . . . . . . . . . . . . 55 9. Security Considerations ........................................55
9.1. Certificates, Authentication, and Authorization . . . . . 55 9.1. Certificates, Authentication, and Authorization ...........55
9.2. (D)TLS Security Considerations . . . . . . . . . . . . . . 56 9.2. (D)TLS Security Considerations ............................56
9.2.1. TLS Version Requirements . . . . . . . . . . . . . . . 56 9.2.1. TLS Version Requirements ...........................56
9.2.2. Perfect Forward Secrecy . . . . . . . . . . . . . . . 57 9.2.2. Perfect Forward Secrecy ............................56
9.3. Use with SNMPv1/SNMPv2c Messages . . . . . . . . . . . . . 57 9.3. Use with SNMPv1/SNMPv2c Messages ..........................56
9.4. MIB Module Security . . . . . . . . . . . . . . . . . . . 57 9.4. MIB Module Security .......................................57
10. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 59 10. IANA Considerations ...........................................58
11. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 59 11. Acknowledgements ..............................................59
12. References . . . . . . . . . . . . . . . . . . . . . . . . . . 60 12. References ....................................................60
12.1. Normative References . . . . . . . . . . . . . . . . . . . 60 12.1. Normative References .....................................60
12.2. Informative References . . . . . . . . . . . . . . . . . . 62 12.2. Informative References ...................................61
Appendix A. Target and Notification Configuration Example . . . . 62 Appendix A. Target and Notification Configuration Example ........63
A.1. Configuring a Notification Originator . . . . . . . . . . 62 A.1. Configuring a Notification Originator .....................63
A.2. Configuring TLSTM to Utilize a Simple Derivation of A.2. Configuring TLSTM to Utilize a Simple Derivation of
tmSecurityName . . . . . . . . . . . . . . . . . . . . . . 63 tmSecurityName ............................................64
A.3. Configuring TLSTM to Utilize Table-Driven Certificate A.3. Configuring TLSTM to Utilize Table-Driven Certificate
Mapping . . . . . . . . . . . . . . . . . . . . . . . . . 64 Mapping ...................................................64
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . . 64
1. Introduction 1. Introduction
It is important to understand the modular SNMPv3 architecture as It is important to understand the modular SNMPv3 architecture as
defined by [RFC3411] and enhanced by the Transport Subsystem defined by [RFC3411] and enhanced by the Transport Subsystem
[RFC5590]. It is also important to understand the terminology of the [RFC5590]. It is also important to understand the terminology of the
SNMPv3 architecture in order to understand where the Transport Model SNMPv3 architecture in order to understand where the Transport Model
described in this document fits into the architecture and how it described in this document fits into the architecture and how it
interacts with the other architecture subsystems. For a detailed interacts with the other architecture subsystems. For a detailed
overview of the documents that describe the current Internet-Standard overview of the documents that describe the current Internet-Standard
Management Framework, please refer to Section 7 of [RFC3410]. Management Framework, please refer to Section 7 of [RFC3410].
This document describes a Transport Model that makes use of the This document describes a Transport Model that makes use of the
Transport Layer Security (TLS) [RFC5246] and the Datagram Transport Transport Layer Security (TLS) [RFC5246] and the Datagram Transport
Layer Security (DTLS) Protocol [RFC4347], within a transport Layer Security (DTLS) Protocol [RFC4347], within a Transport
subsystem [RFC5590]. DTLS is the datagram variant of the Transport Subsystem [RFC5590]. DTLS is the datagram variant of the Transport
Layer Security (TLS) protocol [RFC5246]. The Transport Model in this Layer Security (TLS) protocol [RFC5246]. The Transport Model in this
document is referred to as the Transport Layer Security Transport document is referred to as the Transport Layer Security Transport
Model (TLSTM). TLS and DTLS take advantage of the X.509 public Model (TLSTM). TLS and DTLS take advantage of the X.509 public
keying infrastructure [RFC5280]. While (D)TLS supports multiple keying infrastructure [RFC5280]. While (D)TLS supports multiple
authentication mechanisms, this document only discusses X.509 authentication mechanisms, this document only discusses X.509
certificate based authentication. Although other forms of certificate-based authentication. Although other forms of
authentication are possible they are outside the scope of this authentication are possible, they are outside the scope of this
specification. This transport model is designed to meet the security specification. This transport model is designed to meet the security
and operational needs of network administrators, operating in both and operational needs of network administrators, operating in both
environments where a connectionless (e.g. UDP) transport is environments where a connectionless (e.g., UDP) transport is
preferred and in environments where large quantities of data need to preferred and in environments where large quantities of data need to
be sent (e.g. over a TCP based stream). Both TLS and DTLS integrate be sent (e.g., over a TCP-based stream). Both TLS and DTLS integrate
well into existing public keying infrastructures. This document well into existing public keying infrastructures. This document
supports sending of SNMP messages over TLS/TCP and DTLS/UDP. supports sending of SNMP messages over TLS/TCP and DTLS/UDP.
This document also defines a portion of the Management Information This document also defines a portion of the Management Information
Base (MIB) for use with network management protocols. In particular Base (MIB) for use with network management protocols. In particular,
it defines objects for managing the TLS Transport Model for SNMP. it defines objects for managing the TLS Transport Model for SNMP.
Managed objects are accessed via a virtual information store, termed Managed objects are accessed via a virtual information store, termed
the Management Information Base or MIB. MIB objects are generally the Management Information Base or MIB. MIB objects are generally
accessed through the Simple Network Management Protocol (SNMP). accessed through the Simple Network Management Protocol (SNMP).
Objects in the MIB are defined using the mechanisms defined in the Objects in the MIB are defined using the mechanisms defined in the
Structure of Management Information (SMI). This memo specifies a MIB Structure of Management Information (SMI). This memo specifies a MIB
module that is compliant to the SMIv2, which is described in STD 58: module that is compliant to the SMIv2, which is described in STD 58:
[RFC2578], [RFC2579] and [RFC2580]. [RFC2578], [RFC2579], and [RFC2580].
The diagram shown below gives a conceptual overview of two SNMP The diagram shown below gives a conceptual overview of two SNMP
entities communicating using the TLS Transport Model (shown as "TLS entities communicating using the TLS Transport Model (shown as
TM"). One entity contains a command responder and notification "TLSTM"). One entity contains a command responder and notification
originator application, and the other a command generator and originator application, and the other a command generator and
notification receiver application. It should be understood that this notification receiver application. It should be understood that this
particular mix of application types is an example only and other particular mix of application types is an example only and other
combinations are equally valid. Note: this diagram shows the combinations are equally valid.
Transport Security Model (TSM) being used as the security model which
is defined in [RFC5591]. Note: this diagram shows the Transport Security Model (TSM) being
used as the security model that is defined in [RFC5591].
+---------------------------------------------------------------------+ +---------------------------------------------------------------------+
| Network | | Network |
+---------------------------------------------------------------------+ +---------------------------------------------------------------------+
^ | ^ | ^ | ^ |
|Notifications |Commands |Commands |Notifications |Notifications |Commands |Commands |Notifications
+---|---------------------|-------+ +--|---------------|--------------+ +---|---------------------|-------+ +--|---------------|--------------+
| | V | | | V | | | V | | | V |
| +------------+ +------------+ | | +-----------+ +----------+ | | +------------+ +------------+ | | +-----------+ +----------+ |
| | (D)TLS | | (D)TLS | | | | (D)TLS | | (D)TLS | | | | (D)TLS | | (D)TLS | | | | (D)TLS | | (D)TLS | |
skipping to change at page 8, line 12 skipping to change at page 7, line 12
| SNMP entity | | SNMP entity | | SNMP entity | | SNMP entity |
+---------------------------------+ +---------------------------------+ +---------------------------------+ +---------------------------------+
1.1. Conventions 1.1. Conventions
For consistency with SNMP-related specifications, this document For consistency with SNMP-related specifications, this document
favors terminology as defined in STD 62, rather than favoring favors terminology as defined in STD 62, rather than favoring
terminology that is consistent with non-SNMP specifications. This is terminology that is consistent with non-SNMP specifications. This is
consistent with the IESG decision to not require the SNMPv3 consistent with the IESG decision to not require the SNMPv3
terminology be modified to match the usage of other non-SNMP terminology be modified to match the usage of other non-SNMP
specifications when SNMPv3 was advanced to Full Standard. specifications when SNMPv3 was advanced to a Full Standard.
"Authentication" in this document typically refers to the English "Authentication" in this document typically refers to the English
meaning of "serving to prove the authenticity of" the message, not meaning of "serving to prove the authenticity of" the message, not
data source authentication or peer identity authentication. data source authentication or peer identity authentication.
The terms "manager" and "agent" are not used in this document The terms "manager" and "agent" are not used in this document
because, in the [RFC3411] architecture, all SNMP entities have the because, in the [RFC3411] architecture, all SNMP entities have the
capability of acting as manager, agent, or both depending on the SNMP capability of acting as manager, agent, or both depending on the SNMP
application types supported in the implementation. Where distinction application types supported in the implementation. Where distinction
is required, the application names of command generator, command is required, the application names of command generator, command
responder, notification originator, notification receiver, and proxy responder, notification originator, notification receiver, and proxy
forwarder are used. See "SNMP Applications" [RFC3413] for further forwarder are used. See "SNMP Applications" [RFC3413] for further
information. information.
Large portions of this document simultaneously refer to both TLS and Large portions of this document simultaneously refer to both TLS and
DTLS when discussing TLSTM components that function equally with DTLS when discussing TLSTM components that function equally with
either protocol. "(D)TLS" is used in these places to indicate that either protocol. "(D)TLS" is used in these places to indicate that
the statement applies to either or both protocols as appropriate. the statement applies to either or both protocols as appropriate.
When a distinction between the protocols is needed they are referred When a distinction between the protocols is needed, they are referred
to independently through the use of "TLS" or "DTLS". The Transport to independently through the use of "TLS" or "DTLS". The Transport
Model, however, is named "TLS Transport Model" and refers not to the Model, however, is named "TLS Transport Model" and refers not to the
TLS or DTLS protocol but to the specification in this document, which TLS or DTLS protocol but to the specification in this document, which
includes support for both TLS and DTLS. includes support for both TLS and DTLS.
Throughout this document, the terms "client" and "server" are used to Throughout this document, the terms "client" and "server" are used to
refer to the two ends of the (D)TLS transport connection. The client refer to the two ends of the (D)TLS transport connection. The client
actively opens the (D)TLS connection, and the server passively actively opens the (D)TLS connection, and the server passively
listens for the incoming (D)TLS connection. An SNMP entity may act listens for the incoming (D)TLS connection. An SNMP entity may act
as a (D)TLS client or server or both, depending on the SNMP as a (D)TLS client or server or both, depending on the SNMP
applications supported. applications supported.
The User-Based Security Model (USM) [RFC3414] is a mandatory-to- The User-Based Security Model (USM) [RFC3414] is a mandatory-to-
implement Security Model in STD 62. While (D)TLS and USM frequently implement Security Model in STD 62. While (D)TLS and USM frequently
refer to a user, the terminology preferred in RFC3411 and in this refer to a user, the terminology preferred in RFC 3411 and in this
memo is "principal". A principal is the "who" on whose behalf memo is "principal". A principal is the "who" on whose behalf
services are provided or processing takes place. A principal can be, services are provided or processing takes place. A principal can be,
among other things, an individual acting in a particular role; a set among other things, an individual acting in a particular role; a set
of individuals, with each acting in a particular role; an application of individuals, with each acting in a particular role; an application
or a set of applications, or a combination of these within an or a set of applications, or a combination of these within an
administrative domain. administrative domain.
Throughout this document, the term "session" is used to refer to a Throughout this document, the term "session" is used to refer to a
secure association between two TLS Transport Models that permits the secure association between two TLS Transport Models that permits the
transmission of one or more SNMP messages within the lifetime of the transmission of one or more SNMP messages within the lifetime of the
skipping to change at page 9, line 21 skipping to change at page 8, line 21
TLSTM's specific session and not directly to the (D)TLS protocol's TLSTM's specific session and not directly to the (D)TLS protocol's
session. session.
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119]. document are to be interpreted as described in [RFC2119].
2. The Transport Layer Security Protocol 2. The Transport Layer Security Protocol
(D)TLS provides authentication, data message integrity, and privacy (D)TLS provides authentication, data message integrity, and privacy
at the transport layer. (See [RFC4347]) at the transport layer (see [RFC4347]).
The primary goals of the TLS Transport Model are to provide privacy, The primary goals of the TLS Transport Model are to provide privacy,
peer identity authentication and data integrity between two peer identity authentication and data integrity between two
communicating SNMP entities. The TLS and DTLS protocols provide a communicating SNMP entities. The TLS and DTLS protocols provide a
secure transport upon which the TLSTM is based. Please refer to secure transport upon which the TLSTM is based. Please refer to
[RFC5246] and [RFC4347] for complete descriptions of the protocols. [RFC5246] and [RFC4347] for complete descriptions of the protocols.
3. How the TLSTM fits into the Transport Subsystem 3. How the TLSTM Fits into the Transport Subsystem
A transport model is a component of the Transport Subsystem. The TLS A transport model is a component of the Transport Subsystem. The TLS
Transport Model thus fits between the underlying (D)TLS transport Transport Model thus fits between the underlying (D)TLS transport
layer and the Message Dispatcher [RFC3411] component of the SNMP layer and the Message Dispatcher [RFC3411] component of the SNMP
engine. engine.
The TLS Transport Model will establish a session between itself and The TLS Transport Model will establish a session between itself and
the TLS Transport Model of another SNMP engine. The sending the TLS Transport Model of another SNMP engine. The sending
transport model passes unencrypted and unauthenticated messages from transport model passes unencrypted and unauthenticated messages from
the Dispatcher to (D)TLS to be encrypted and authenticated, and the the Dispatcher to (D)TLS to be encrypted and authenticated, and the
skipping to change at page 10, line 10 skipping to change at page 9, line 10
Dispatcher to another SNMP Message Dispatcher. If multiple SNMP Dispatcher to another SNMP Message Dispatcher. If multiple SNMP
messages are needed to be passed between two SNMP applications they messages are needed to be passed between two SNMP applications they
MAY be passed through the same session. A TLSTM implementation MAY be passed through the same session. A TLSTM implementation
engine MAY choose to close the session to conserve resources. engine MAY choose to close the session to conserve resources.
The TLS Transport Model of an SNMP engine will perform the The TLS Transport Model of an SNMP engine will perform the
translation between (D)TLS-specific security parameters and SNMP- translation between (D)TLS-specific security parameters and SNMP-
specific, model-independent parameters. specific, model-independent parameters.
The diagram below depicts where the TLS Transport Model (shown as The diagram below depicts where the TLS Transport Model (shown as
"(D)TLS TM") fits into the architecture described in RFC3411 and the "(D)TLS TM") fits into the architecture described in RFC 3411 and the
Transport Subsystem: Transport Subsystem:
+------------------------------+ +------------------------------+
| Network | | Network |
+------------------------------+ +------------------------------+
^ ^ ^ ^ ^ ^
| | | | | |
v v v v v v
+-------------------------------------------------------------------+ +-------------------------------------------------------------------+
| +--------------------------------------------------+ | | +--------------------------------------------------+ |
skipping to change at page 11, line 39 skipping to change at page 10, line 40
message has not been modified during its transmission through the message has not been modified during its transmission through the
network, data has not been altered or destroyed in an network, data has not been altered or destroyed in an
unauthorized manner, and data sequences have not been altered to unauthorized manner, and data sequences have not been altered to
an extent greater than can occur non-maliciously. an extent greater than can occur non-maliciously.
2. Masquerade - The masquerade threat is the danger that management 2. Masquerade - The masquerade threat is the danger that management
operations unauthorized for a given principal may be attempted by operations unauthorized for a given principal may be attempted by
assuming the identity of another principal that has the assuming the identity of another principal that has the
appropriate authorizations. appropriate authorizations.
The TLSTM verifies of the identity of the (D)TLS server through The TLSTM verifies the identity of the (D)TLS server through the
the use of the (D)TLS protocol and X.509 certificates. A TLS use of the (D)TLS protocol and X.509 certificates. A TLS
Transport Model implementation MUST support authentication of Transport Model implementation MUST support the authentication of
both the server and the client. both the server and the client.
3. Message stream modification - The re-ordering, delay or replay of 3. Message stream modification - The re-ordering, delay, or replay
messages can and does occur through the natural operation of many of messages can and does occur through the natural operation of
connectionless transport services. The message stream many connectionless transport services. The message stream
modification threat is the danger that messages may be modification threat is the danger that messages may be
maliciously re-ordered, delayed or replayed to an extent which is maliciously re-ordered, delayed or replayed to an extent that is
greater than can occur through the natural operation of greater than can occur through the natural operation of
connectionless transport services, in order to effect connectionless transport services, in order to effect
unauthorized management operations. unauthorized management operations.
(D)TLS provides replay protection with a MAC that includes a (D)TLS provides replay protection with a Message Authentication
sequence number. Since UDP provides no sequencing ability, DTLS Code (MAC) that includes a sequence number. Since UDP provides
uses a sliding window protocol with the sequence number used for no sequencing ability, DTLS uses a sliding window protocol with
replay protection (see [RFC4347]). the sequence number used for replay protection (see [RFC4347]).
4. Disclosure - The disclosure threat is the danger of eavesdropping 4. Disclosure - The disclosure threat is the danger of eavesdropping
on the exchanges between SNMP engines. on the exchanges between SNMP engines.
(D)TLS provides protection against the disclosure of information (D)TLS provides protection against the disclosure of information
to unauthorized recipients or eavesdroppers by allowing for to unauthorized recipients or eavesdroppers by allowing for
encryption of all traffic between SNMP engines. A TLS Transport encryption of all traffic between SNMP engines. A TLS Transport
Model implementation MUST support message encryption to protect Model implementation MUST support message encryption to protect
sensitive data from eavesdropping attacks. sensitive data from eavesdropping attacks.
5. Denial of Service - the RFC 3411 architecture [RFC3411] states 5. Denial of Service - the RFC 3411 architecture [RFC3411] states
that denial of service (DoS) attacks need not be addressed by an that denial-of-service (DoS) attacks need not be addressed by an
SNMP security protocol. However, connectionless transports (like SNMP security protocol. However, connectionless transports (like
DTLS over UDP) are susceptible to a variety of denial of service DTLS over UDP) are susceptible to a variety of DoS attacks
attacks because they are more vulnerable to spoofed IP addresses. because they are more vulnerable to spoofed IP addresses. See
See Section 4.2 for details how the cookie mechanism is used. Section 4.2 for details on how the cookie mechanism is used.
Note, however, that this mechanism does not provide any defense Note, however, that this mechanism does not provide any defense
against denial of service attacks mounted from valid IP against DoS attacks mounted from valid IP addresses.
addresses.
See Section 9 for more detail on the security considerations See Section 9 for more detail on the security considerations
associated with the TLSTM and these security threats. associated with the TLSTM and these security threats.
3.1.2. Message Protection 3.1.2. Message Protection
The RFC 3411 architecture recognizes three levels of security: The RFC 3411 architecture recognizes three levels of security:
o without authentication and without privacy (noAuthNoPriv) o without authentication and without privacy (noAuthNoPriv)
o with authentication but without privacy (authNoPriv) o with authentication but without privacy (authNoPriv)
o with authentication and with privacy (authPriv) o with authentication and with privacy (authPriv)
The TLS Transport Model determines from (D)TLS the identity of the The TLS Transport Model determines from (D)TLS the identity of the
authenticated principal, the transport type and the transport address authenticated principal, the transport type and the transport address
associated with an incoming message. The TLS Transport Model associated with an incoming message. The TLS Transport Model
provides the identity and destination type and address to (D)TLS for provides the identity and destination type and address to (D)TLS for
outgoing messages. outgoing messages.
When an application requests a session for a message it also requests When an application requests a session for a message, it also
a security level for that session. The TLS Transport Model MUST requests a security level for that session. The TLS Transport Model
ensure that the (D)TLS connection provides security at least as high MUST ensure that the (D)TLS connection provides security at least as
as the requested level of security. How the security level is high as the requested level of security. How the security level is
translated into the algorithms used to provide data integrity and translated into the algorithms used to provide data integrity and
privacy is implementation-dependent. However, the NULL integrity and privacy is implementation dependent. However, the NULL integrity and
encryption algorithms MUST NOT be used to fulfill security level encryption algorithms MUST NOT be used to fulfill security level
requests for authentication or privacy. Implementations MAY choose requests for authentication or privacy. Implementations MAY choose
to force (D)TLS to only allow cipher_suites that provide both to force (D)TLS to only allow cipher_suites that provide both
authentication and privacy to guarantee this assertion. authentication and privacy to guarantee this assertion.
If a suitable interface between the TLS Transport Model and the If a suitable interface between the TLS Transport Model and the
(D)TLS Handshake Protocol is implemented to allow the selection of (D)TLS Handshake Protocol is implemented to allow the selection of
security level dependent algorithms (for example a security level to security-level-dependent algorithms (for example, a security level to
cipher_suites mapping table) then different security levels may be cipher_suites mapping table), then different security levels may be
utilized by the application. utilized by the application.
The authentication, integrity and privacy algorithms used by the The authentication, integrity, and privacy algorithms used by the
(D)TLS Protocols may vary over time as the science of cryptography (D)TLS Protocols may vary over time as the science of cryptography
continues to evolve and the development of (D)TLS continues over continues to evolve and the development of (D)TLS continues over
time. Implementers are encouraged to plan for changes in operator time. Implementers are encouraged to plan for changes in operator
trust of particular algorithms. Implementations SHOULD offer trust of particular algorithms. Implementations SHOULD offer
configuration settings for mapping algorithms to SNMPv3 security configuration settings for mapping algorithms to SNMPv3 security
levels. levels.
3.1.3. (D)TLS Connections 3.1.3. (D)TLS Connections
(D)TLS connections are opened by the TLS Transport Model during the (D)TLS connections are opened by the TLS Transport Model during the
skipping to change at page 13, line 42 skipping to change at page 12, line 48
anticipation of outgoing messages. This approach might be useful to anticipation of outgoing messages. This approach might be useful to
ensure that a (D)TLS connection to a given target can be established ensure that a (D)TLS connection to a given target can be established
before it becomes important to send a message over the (D)TLS before it becomes important to send a message over the (D)TLS
connection. Of course, there is no guarantee that a pre-established connection. Of course, there is no guarantee that a pre-established
session will still be valid when needed. session will still be valid when needed.
DTLS connections, when used over UDP, are uniquely identified within DTLS connections, when used over UDP, are uniquely identified within
the TLS Transport Model by the combination of transportDomain, the TLS Transport Model by the combination of transportDomain,
transportAddress, tmSecurityName, and requestedSecurityLevel transportAddress, tmSecurityName, and requestedSecurityLevel
associated with each session. Each unique combination of these associated with each session. Each unique combination of these
parameters MUST have a locally-chosen unique tlstmSessionID for each parameters MUST have a locally chosen unique tlstmSessionID for each
active session. For further information see Section 5. TLS over TCP active session. For further information, see Section 5. TLS over
sessions, on the other hand, do not require a unique pairing of TCP sessions, on the other hand, do not require a unique pairing of
address and port attributes since their lower layer protocols (TCP) address and port attributes since their lower-layer protocols (TCP)
already provide adequate session framing. But they must still already provide adequate session framing. But they must still
provide a unique tlstmSessionID for referencing the session. provide a unique tlstmSessionID for referencing the session.
The tlstmSessionID identifier MUST NOT change during the entire The tlstmSessionID MUST NOT change during the entire duration of the
duration of the session from the TLSTM's perspective, and MUST session from the TLSTM's perspective, and MUST uniquely identify a
uniquely identify a single session. As an implementation hint: note single session. As an implementation hint: note that the (D)TLS
that the (D)TLS internal SessionID does not meet these requirements, internal SessionID does not meet these requirements, since it can
since it can change over the life of the connection as seen by the change over the life of the connection as seen by the TLSTM (for
TLSTM (for example, during renegotiation), and does not necessarily example, during renegotiation), and does not necessarily uniquely
uniquely identify a TLSTM session (there can be multiple TLSTM identify a TLSTM session (there can be multiple TLSTM sessions
sessions sharing the same D(TLS) internal SessionID). sharing the same D(TLS) internal SessionID).
3.2. Security Parameter Passing 3.2. Security Parameter Passing
For the (D)TLS server-side, (D)TLS-specific security parameters For the (D)TLS server-side, (D)TLS-specific security parameters
(i.e., cipher_suites, X.509 certificate fields, IP address and port) (i.e., cipher_suites, X.509 certificate fields, IP addresses, and
are translated by the TLS Transport Model into security parameters ports) are translated by the TLS Transport Model into security
for the TLS Transport Model and security model (e.g., parameters for the TLS Transport Model and security model (e.g.,
tmSecurityLevel, tmSecurityName, transportDomain, transportAddress). tmSecurityLevel, tmSecurityName, transportDomain, transportAddress).
The transport-related and (D)TLS-security-related information, The transport-related and (D)TLS-security-related information,
including the authenticated identity, are stored in a cache including the authenticated identity, are stored in a cache
referenced by tmStateReference. referenced by tmStateReference.
For the (D)TLS client-side, the TLS Transport Model takes input For the (D)TLS client side, the TLS Transport Model takes input
provided by the Dispatcher in the sendMessage() Abstract Service provided by the Dispatcher in the sendMessage() Abstract Service
Interface (ASI) and input from the tmStateReference cache. The Interface (ASI) and input from the tmStateReference cache. The
(D)TLS Transport Model converts that information into suitable (D)TLS Transport Model converts that information into suitable
security parameters for (D)TLS and establishes sessions as needed. security parameters for (D)TLS and establishes sessions as needed.
The elements of procedure in Section 5 discuss these concepts in much The elements of procedure in Section 5 discuss these concepts in much
greater detail. greater detail.
3.3. Notifications and Proxy 3.3. Notifications and Proxy
(D)TLS connections may be initiated by (D)TLS clients on behalf of (D)TLS connections may be initiated by (D)TLS clients on behalf of
SNMP appplications that initiate communications, such as command SNMP applications that initiate communications, such as command
generators, notification originators, proxy forwarders. Command generators, notification originators, proxy forwarders. Command
generators are frequently operated by a human, but notification generators are frequently operated by a human, but notification
originators and proxy forwarders are usually unmanned automated originators and proxy forwarders are usually unmanned automated
processes. The targets to whom notifications and proxied requests processes. The targets to whom notifications and proxied requests
should be sent is typically determined and configured by a network should be sent is typically determined and configured by a network
administrator. administrator.
The SNMP-TARGET-MIB module [RFC3413] contains objects for defining The SNMP-TARGET-MIB module [RFC3413] contains objects for defining
management targets, including transportDomain, transportAddress, management targets, including transportDomain, transportAddress,
securityName, securityModel, and securityLevel parameters, for securityName, securityModel, and securityLevel parameters, for
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When configuring a (D)TLS target, the snmpTargetAddrTDomain and When configuring a (D)TLS target, the snmpTargetAddrTDomain and
snmpTargetAddrTAddress parameters in snmpTargetAddrTable SHOULD be snmpTargetAddrTAddress parameters in snmpTargetAddrTable SHOULD be
set to the snmpTLSTCPDomain or snmpDTLSUDPDomain object and an set to the snmpTLSTCPDomain or snmpDTLSUDPDomain object and an
appropriate snmpTLSAddress value. When used with the SNMPv3 message appropriate snmpTLSAddress value. When used with the SNMPv3 message
processing model, the snmpTargetParamsMPModel column of the processing model, the snmpTargetParamsMPModel column of the
snmpTargetParamsTable SHOULD be set to a value of 3. The snmpTargetParamsTable SHOULD be set to a value of 3. The
snmpTargetParamsSecurityName SHOULD be set to an appropriate snmpTargetParamsSecurityName SHOULD be set to an appropriate
securityName value and the snmpTlstmParamsClientFingerprint parameter securityName value and the snmpTlstmParamsClientFingerprint parameter
of the snmpTlstmParamsTable SHOULD be set a value that refers to a of the snmpTlstmParamsTable SHOULD be set a value that refers to a
locally held certificate (and the corresponding private key) to be locally held certificate (and the corresponding private key) to be
used. Other parameters, for example cryptographic configuration such used. Other parameters, for example, cryptographic configuration
as which cipher suites to use, must come from configuration such as which cipher_suites to use, must come from configuration
mechanisms not defined in this document. mechanisms not defined in this document.
The securityName defined in the snmpTargetParamsSecurityName column The securityName defined in the snmpTargetParamsSecurityName column
will be used by the access control model to authorize any will be used by the access control model to authorize any
notifications that need to be sent. notifications that need to be sent.
4. Elements of the Model 4. Elements of the Model
This section contains definitions required to realize the (D)TLS This section contains definitions required to realize the (D)TLS
Transport Model defined by this document. Transport Model defined by this document.
4.1. X.509 Certificates 4.1. X.509 Certificates
(D)TLS can make use of X.509 certificates for authentication of both (D)TLS can make use of X.509 certificates for authentication of both
sides of the transport. This section discusses the use of X.509 sides of the transport. This section discusses the use of X.509
certificates in the TLSTM. certificates in the TLSTM.
While (D)TLS supports multiple authentication mechanisms, this While (D)TLS supports multiple authentication mechanisms, this
document only discusses X.509 certificate based authentication; other document only discusses X.509-certificate-based authentication; other
forms of authentication are outside the scope of this specification. forms of authentication are outside the scope of this specification.
TLSTM implementations are REQUIRED to support X.509 certificates. TLSTM implementations are REQUIRED to support X.509 certificates.
4.1.1. Provisioning for the Certificate 4.1.1. Provisioning for the Certificate
Authentication using (D)TLS will require that SNMP entities have Authentication using (D)TLS will require that SNMP entities have
certificates, either signed by trusted certification authorities, or certificates, either signed by trusted Certification Authorities
self-signed. Furthermore, SNMP entities will most commonly need to (CAs), or self signed. Furthermore, SNMP entities will most commonly
be provisioned with root certificates which represent the list of need to be provisioned with root certificates that represent the list
trusted certificate authorities that an SNMP entity can use for of trusted CAs that an SNMP entity can use for certificate
certificate verification. SNMP entities SHOULD also be provisioned verification. SNMP entities SHOULD also be provisioned with a X.509
with a X.509 certificate revocation mechanism which can be used to certificate revocation mechanism which can be used to verify that a
verify that a certificate has not been revoked. Trusted public keys certificate has not been revoked. Trusted public keys from either CA
from either CA certificates and/or self-signed certificates MUST be certificates and/or self-signed certificates MUST be installed into
installed into the server through a trusted out of band mechanism and the server through a trusted out-of-band mechanism and their
their authenticity MUST be verified before access is granted. authenticity MUST be verified before access is granted.
Having received a certificate from a connecting TLSTM client, the Having received a certificate from a connecting TLSTM client, the
authenticated tmSecurityName of the principal is derived using the authenticated tmSecurityName of the principal is derived using the
snmpTlstmCertToTSNTable. This table allows mapping of incoming snmpTlstmCertToTSNTable. This table allows mapping of incoming
connections to tmSecurityNames through defined transformations. The connections to tmSecurityNames through defined transformations. The
transformations defined in the SNMP-TLS-TM-MIB include: transformations defined in the SNMP-TLS-TM-MIB include:
o Mapping a certificate's subjectAltName or CommonName components to o Mapping a certificate's subjectAltName or CommonName components to
a tmSecurityName, or a tmSecurityName, or
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An example of this type of mapping setup can be found in Appendix A. An example of this type of mapping setup can be found in Appendix A.
This tmSecurityName may be later translated from a TLSTM specific This tmSecurityName may be later translated from a TLSTM specific
tmSecurityName to a SNMP engine securityName by the security model. tmSecurityName to a SNMP engine securityName by the security model.
A security model, like the TSM security model [RFC5591], may perform A security model, like the TSM security model [RFC5591], may perform
an identity mapping or a more complex mapping to derive the an identity mapping or a more complex mapping to derive the
securityName from the tmSecurityName offered by the TLS Transport securityName from the tmSecurityName offered by the TLS Transport
Model. Model.
The standard VACM access control model constrains securityNames to be The standard View-Based Access Control Model (VACM) access control
32 octets or less in length. A TLSTM generated tmSecurityName, model constrains securityNames to be 32 octets or less in length. A
possibly in combination with a messaging or security model that TLSTM generated tmSecurityName, possibly in combination with a
increases the length of the securityName, might cause the messaging or security model that increases the length of the
securityName length to exceed 32 octets. For example, a 32 octet securityName, might cause the securityName length to exceed 32
tmSecurityName derived from an IPv6 address, paired with a TSM octets. For example, a 32-octet tmSecurityName derived from an IPv6
prefix, will generate a 36 octet securityName. Such a securityName address, paired with a TSM prefix, will generate a 36-octet
will not be able to be used with standard VACM or TARGET MIB modules. securityName. Such a securityName will not be able to be used with
Operators should be careful to select algorithms and subjectAltNames standard VACM or TARGET MIB modules. Operators should be careful to
to avoid this situation. select algorithms and subjectAltNames to avoid this situation.
A pictorial view of the complete transformation process (using the A pictorial view of the complete transformation process (using the
TSM security model for the example) is shown below: TSM security model for the example) is shown below:
+-------------+ +-------+ +-----+ +-------------+ +-------+ +-----+
| Certificate | | | | | | Certificate | | | | |
| Path | | TLSTM | tmSecurityName | TSM | | Path | | TLSTM | tmSecurityName | TSM |
| Validation | --> | | ----------------->| | | Validation | --> | | ----------------->| |
+-------------+ +-------+ +-----+ +-------------+ +-------+ +-----+
| |
| securityName | securityName
V V
+-------------+ +-------------+
| application | | application |
+-------------+ +-------------+
4.2. (D)TLS Usage 4.2. (D)TLS Usage
(D)TLS MUST negotiate a cipher suite that uses X.509 certificates for (D)TLS MUST negotiate a cipher_suite that uses X.509 certificates for
authentication, and MUST authenticate both the client and the server. authentication, and MUST authenticate both the client and the server.
The mandatory-to-implement cipher suite is specified in the TLS The mandatory-to-implement cipher_suite is specified in the TLS
specification [RFC5246]. specification [RFC5246].
TLSTM verifies the certificates when the connection is opened (see TLSTM verifies the certificates when the connection is opened (see
Section 5.3). For this reason, TLS renegotiation with different Section 5.3). For this reason, TLS renegotiation with different
certificates MUST NOT be done. That is, implementations MUST either certificates MUST NOT be done. That is, implementations MUST either
disable renegotiation completely (RECOMMENDED), or MUST present the disable renegotiation completely (RECOMMENDED), or they MUST present
same certificate during renegotiation (and MUST verify that the other the same certificate during renegotiation (and MUST verify that the
end presented the same certificate). other end presented the same certificate).
For DTLS over UDP, each SNMP message MUST be placed in a single UDP For DTLS over UDP, each SNMP message MUST be placed in a single UDP
datagram; it MAY be split to multiple DTLS records. In other words, datagram; it MAY be split to multiple DTLS records. In other words,
if a single datagram contains multiple DTLS application_data records, if a single datagram contains multiple DTLS application_data records,
they are concatenated when received. The TLSTM implementation SHOULD they are concatenated when received. The TLSTM implementation SHOULD
return an error if the SNMP message does not fit in the UDP datagram, return an error if the SNMP message does not fit in the UDP datagram,
and thus cannot be sent. and thus cannot be sent.
For DTLS over UDP, the DTLS server implementation MUST support DTLS For DTLS over UDP, the DTLS server implementation MUST support DTLS
cookies ([RFC4347] already requires that clients support DTLS cookies ([RFC4347] already requires that clients support DTLS
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Transport Model and the Dispatcher. Transport Model and the Dispatcher.
The services are described as primitives of an abstract service The services are described as primitives of an abstract service
interface (ASI) and the inputs and outputs are described as abstract interface (ASI) and the inputs and outputs are described as abstract
data elements as they are passed in these abstract service data elements as they are passed in these abstract service
primitives. primitives.
4.3.1. SNMP Services for an Outgoing Message 4.3.1. SNMP Services for an Outgoing Message
The Dispatcher passes the information to the TLS Transport Model The Dispatcher passes the information to the TLS Transport Model
using the ASI defined in the transport subsystem: using the ASI defined in the Transport Subsystem:
statusInformation = statusInformation =
sendMessage( sendMessage(
IN destTransportDomain -- transport domain to be used IN destTransportDomain -- transport domain to be used
IN destTransportAddress -- transport address to be used IN destTransportAddress -- transport address to be used
IN outgoingMessage -- the message to send IN outgoingMessage -- the message to send
IN outgoingMessageLength -- its length IN outgoingMessageLength -- its length
IN tmStateReference -- reference to transport state IN tmStateReference -- reference to transport state
) )
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tmStateReference: A reference used to pass model-specific and tmStateReference: A reference used to pass model-specific and
mechanism-specific parameters between the Transport Subsystem and mechanism-specific parameters between the Transport Subsystem and
transport-aware Security Models. transport-aware Security Models.
4.4. Cached Information and References 4.4. Cached Information and References
When performing SNMP processing, there are two levels of state When performing SNMP processing, there are two levels of state
information that may need to be retained: the immediate state linking information that may need to be retained: the immediate state linking
a request-response pair, and potentially longer-term state relating a request-response pair, and potentially longer-term state relating
to transport and security. "Transport Subsystem for the Simple to transport and security. "Transport Subsystem for the Simple
Network Management Protocol" [RFC5590] defines general requirements Network Management Protocol (SNMP)" [RFC5590] defines general
for caches and references. requirements for caches and references.
4.4.1. TLS Transport Model Cached Information 4.4.1. TLS Transport Model Cached Information
The TLS Transport Model has specific responsibilities regarding the The TLS Transport Model has specific responsibilities regarding the
cached information. See the Elements of Procedure in Section 5 for cached information. See the Elements of Procedure in Section 5 for
detailed processing instructions on the use of the tmStateReference detailed processing instructions on the use of the tmStateReference
fields by the TLS Transport Model. fields by the TLS Transport Model.
4.4.1.1. tmSecurityName 4.4.1.1. tmSecurityName
The tmSecurityName MUST be a human-readable name (in snmpAdminString The tmSecurityName MUST be a human-readable name (in snmpAdminString
format) representing the identity that has been set according to the format) representing the identity that has been set according to the
procedures in Section 5. The tmSecurityName MUST be constant for all procedures in Section 5. The tmSecurityName MUST be constant for all
traffic passing through a single TLSTM session. Messages MUST NOT be traffic passing through a single TLSTM session. Messages MUST NOT be
sent through an existing (D)TLS connection that was established using sent through an existing (D)TLS connection that was established using
a different tmSecurityName. a different tmSecurityName.
On the (D)TLS server side of a connection the tmSecurityName is On the (D)TLS server side of a connection, the tmSecurityName is
derived using the procedures described in Section 5.3.2 and the SNMP- derived using the procedures described in Section 5.3.2 and the SNMP-
TLS-TM-MIB's snmpTlstmCertToTSNTable DESCRIPTION clause. TLS-TM-MIB's snmpTlstmCertToTSNTable DESCRIPTION clause.
On the (D)TLS client side of a connection the tmSecurityName is On the (D)TLS client side of a connection, the tmSecurityName is
presented to the TLS Transport Model by the application (possibly presented to the TLS Transport Model by the security model through
because of configuration specified in the SNMP-TARGET-MIB). The the tmStateReference. This tmSecurityName is typically a copy of or
Security Model likely derived the tmSecurityName from the is derived from the securityName that was passed by application
(possibly because of configuration specified in the SNMP-TARGET-MIB).
The Security Model likely derived the tmSecurityName from the
securityName presented to the Security Model by the application securityName presented to the Security Model by the application
(possibly because of configuration specified in the SNMP-TARGET-MIB). (possibly because of configuration specified in the SNMP-TARGET-MIB).
Transport-model-aware security models derive tmSecurityName from a Transport-Model-aware security models derive tmSecurityName from a
securityName, possibly configured in MIB modules for notifications securityName, possibly configured in MIB modules for notifications
and access controls. Transport Models SHOULD use predictable and access controls. Transport Models SHOULD use predictable
tmSecurityNames so operators will know what to use when configuring tmSecurityNames so operators will know what to use when configuring
MIB modules that use securityNames derived from tmSecurityNames. The MIB modules that use securityNames derived from tmSecurityNames. The
TLSTM generates predictable tmSecurityNames based on the TLSTM generates predictable tmSecurityNames based on the
configuration found in the SNMP-TLS-TM-MIB's snmpTlstmCertToTSNTable configuration found in the SNMP-TLS-TM-MIB's snmpTlstmCertToTSNTable
and relies on the network operators to have configured this table and relies on the network operators to have configured this table
appropriately. appropriately.
4.4.1.2. tmSessionID 4.4.1.2. tmSessionID
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Section 5.1.2 describes the transport processing required once the Section 5.1.2 describes the transport processing required once the
(D)TLS processing has been completed. This will be needed for all (D)TLS processing has been completed. This will be needed for all
(D)TLS-based connections. (D)TLS-based connections.
5.1.1. DTLS over UDP Processing for Incoming Messages 5.1.1. DTLS over UDP Processing for Incoming Messages
Demultiplexing of incoming packets into separate DTLS sessions MUST Demultiplexing of incoming packets into separate DTLS sessions MUST
be implemented. For connection-oriented transport protocols, such as be implemented. For connection-oriented transport protocols, such as
TCP, the transport protocol takes care of demultiplexing incoming TCP, the transport protocol takes care of demultiplexing incoming
packets to the right connection. Depending on the DTLS packets to the right connection. For DTLS over UDP, this
implementation, for DTLS over UDP, this demultiplexing will either demultiplexing will either need to be done within the DTLS
need to be done within the TLS implementation or by the TLSTM implementation, if supported, or by the TLSTM implementation.
implementation.
Like TCP, DTLS over UDP uses the four-tuple <source IP, destination Like TCP, DTLS over UDP uses the four-tuple <source IP, destination
IP, source port, destination port> for identifying the connection IP, source port, destination port> for identifying the connection
(and relevant DTLS connection state). This means that when (and relevant DTLS connection state). This means that when
establishing a new session, implementations MUST use a different UDP establishing a new session, implementations MUST use a different UDP
source port number for each active connection to a remote destination source port number for each active connection to a remote destination
IP-address/port-number combination to ensure the remote entity can IP-address/port-number combination to ensure the remote entity can
disambiguate between multiple connections. disambiguate between multiple connections.
If demultiplexing received UDP datagrams to DTLS connection state is If demultiplexing received UDP datagrams to DTLS connection state is
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If the DTLS implementation decides to continue with the If the DTLS implementation decides to continue with the
connection and allocate state for it, it returns a new DTLS connection and allocate state for it, it returns a new DTLS
connection handle (an implementation dependent detail). In connection handle (an implementation dependent detail). In
this case, TLSTM selects a new tlstmSessionId, and caches this case, TLSTM selects a new tlstmSessionId, and caches
this and the DTLS connection handle as a new entry in the this and the DTLS connection handle as a new entry in the
LCD (indexed by the transport parameters). If the DTLS LCD (indexed by the transport parameters). If the DTLS
implementation returns an error or does not allocate implementation returns an error or does not allocate
connection state (which can happen with the stateless cookie connection state (which can happen with the stateless cookie
exchange), processing stops. exchange), processing stops.
2b) If a session does exist in the LCD then its DTLS connection 2b) If a session does exist in the LCD, then its DTLS connection
handle (an implementation dependent detail) and its handle (an implementation dependent detail) and its
tlstmSessionId is extracted from the LCD. The UDP packet tlstmSessionId is extracted from the LCD. The UDP packet
and the connection handle is passed to the DTLS and the connection handle is passed to the DTLS
implementation. If the DTLS implementation returns success implementation. If the DTLS implementation returns success
but does not return an incomingMessage and an but does not return an incomingMessage and an
incomingMessageLength then processing stops (this is the incomingMessageLength then processing stops (this is the
case when the UDP datagram contained DTLS handshake case when the UDP datagram contained DTLS handshake
messages, for example). If the DTLS implementation returns messages, for example). If the DTLS implementation returns
an error then processing stops. an error then processing stops.
skipping to change at page 23, line 35 skipping to change at page 22, line 41
messages originating from either TLS or DTLS to ensure they're messages originating from either TLS or DTLS to ensure they're
complete and single. For example, multiple SNMP messages can be complete and single. For example, multiple SNMP messages can be
passed through a single DTLS message and partial SNMP messages may be passed through a single DTLS message and partial SNMP messages may be
received from a TLS stream. These steps describe the processing of a received from a TLS stream. These steps describe the processing of a
singular SNMP message after it has been delivered from the (D)TLS singular SNMP message after it has been delivered from the (D)TLS
stream. stream.
1) Determine the tlstmSessionID for the incoming message. The 1) Determine the tlstmSessionID for the incoming message. The
tlstmSessionID MUST be a unique session identifier for this tlstmSessionID MUST be a unique session identifier for this
(D)TLS connection. The contents and format of this identifier (D)TLS connection. The contents and format of this identifier
are implementation-dependent as long as it is unique to the are implementation dependent as long as it is unique to the
session. A session identifier MUST NOT be reused until all session. A session identifier MUST NOT be reused until all
references to it are no longer in use. The tmSessionID is equal references to it are no longer in use. The tmSessionID is equal
to the tlstmSessionID discussed in Section 5.1.1. tmSessionID to the tlstmSessionID discussed in Section 5.1.1. tmSessionID
refers to the session identifier when stored in the refers to the session identifier when stored in the
tmStateReference and tlstmSessionID refers to the session tmStateReference and tlstmSessionID refers to the session
identifier when stored in the LCD. They MUST always be equal identifier when stored in the LCD. They MUST always be equal
when processing a given session's traffic. when processing a given session's traffic.
If this is the first message received through this session and If this is the first message received through this session, and
the session does not have an assigned tlstmSessionID yet then the the session does not have an assigned tlstmSessionID yet, then
snmpTlstmSessionAccepts counter is incremented and a the snmpTlstmSessionAccepts counter is incremented and a
tlstmSessionID for the session is created. This will only happen tlstmSessionID for the session is created. This will only happen
on the server side of a connection because a client would have on the server side of a connection because a client would have
already assigned a tlstmSessionID during the openSession() already assigned a tlstmSessionID during the openSession()
invocation. Implementations may have performed the procedures invocation. Implementations may have performed the procedures
described in Section 5.3.2 prior to this point or they may described in Section 5.3.2 prior to this point or they may
perform them now, but the procedures described in Section 5.3.2 perform them now, but the procedures described in Section 5.3.2
MUST be performed before continuing beyond this point. MUST be performed before continuing beyond this point.
2) Create a tmStateReference cache for the subsequent reference and 2) Create a tmStateReference cache for the subsequent reference and
assign the following values within it: assign the following values within it:
tmTransportDomain = snmpTLSTCPDomain or snmpDTLSUDPDomain as tmTransportDomain = snmpTLSTCPDomain or snmpDTLSUDPDomain as
appropriate. appropriate.
tmTransportAddress = The address the message originated from. tmTransportAddress = The address from which the message
originated.
tmSecurityLevel = The derived tmSecurityLevel for the session, tmSecurityLevel = The derived tmSecurityLevel for the session,
as discussed in Section 3.1.2 and Section 5.3. as discussed in Sections 3.1.2 and 5.3.
tmSecurityName = The derived tmSecurityName for the session as tmSecurityName = The derived tmSecurityName for the session as
discussed in Section 5.3. This value MUST be constant during discussed in Section 5.3. This value MUST be constant during
the lifetime of the session. the lifetime of the session.
tmSessionID = The tlstmSessionID described in step 1 above. tmSessionID = The tlstmSessionID described in step 1 above.
3) The incomingMessage and incomingMessageLength are assigned values 3) The incomingMessage and incomingMessageLength are assigned values
from the (D)TLS processing. from the (D)TLS processing.
skipping to change at page 25, line 18 skipping to change at page 24, line 31
1) If tmStateReference does not refer to a cache containing values 1) If tmStateReference does not refer to a cache containing values
for tmTransportDomain, tmTransportAddress, tmSecurityName, for tmTransportDomain, tmTransportAddress, tmSecurityName,
tmRequestedSecurityLevel, and tmSameSecurity, then increment the tmRequestedSecurityLevel, and tmSameSecurity, then increment the
snmpTlstmSessionInvalidCaches counter, discard the message, and snmpTlstmSessionInvalidCaches counter, discard the message, and
return the error indication in the statusInformation. Processing return the error indication in the statusInformation. Processing
of this message stops. of this message stops.
2) Extract the tmSessionID, tmTransportDomain, tmTransportAddress, 2) Extract the tmSessionID, tmTransportDomain, tmTransportAddress,
tmSecurityName, tmRequestedSecurityLevel, and tmSameSecurity tmSecurityName, tmRequestedSecurityLevel, and tmSameSecurity
values from the tmStateReference. Note: The tmSessionID value values from the tmStateReference. Note: the tmSessionID value
may be undefined if no session exists yet over which the message may be undefined if no session exists yet over which the message
can be sent. can be sent.
3) If tmSameSecurity is true and either tmSessionID is undefined or 3) If tmSameSecurity is true and tmSessionID is either undefined or
refers to a session that is no longer open then increment the refers to a session that is no longer open, then increment the
snmpTlstmSessionNoSessions counter, discard the message and snmpTlstmSessionNoSessions counter, discard the message, and
return the error indication in the statusInformation. Processing return the error indication in the statusInformation. Processing
of this message stops. of this message stops.
4) If tmSameSecurity is false and tmSessionID refers to a session 4) If tmSameSecurity is false and tmSessionID refers to a session
that is no longer available then an implementation SHOULD open a that is no longer available, then an implementation SHOULD open a
new session using the openSession() ASI (described in greater new session, using the openSession() ASI (described in greater
detail in step 5b). Instead of opening a new session an detail in step 5b). Instead of opening a new session an
implementation MAY return a snmpTlstmSessionNoSessions error to implementation MAY return a snmpTlstmSessionNoSessions error to
the calling module and stop processing of the message. the calling module and stop the processing of the message.
5) If tmSessionID is undefined, then use tmTransportDomain, 5) If tmSessionID is undefined, then use tmTransportDomain,
tmTransportAddress, tmSecurityName and tmRequestedSecurityLevel tmTransportAddress, tmSecurityName, and tmRequestedSecurityLevel
to see if there is a corresponding entry in the LCD suitable to to see if there is a corresponding entry in the LCD suitable to
send the message over. send the message over.
5a) If there is a corresponding LCD entry, then this session 5a) If there is a corresponding LCD entry, then this session
will be used to send the message. will be used to send the message.
5b) If there is no corresponding LCD entry, then open a session 5b) If there is no corresponding LCD entry, then open a session
using the openSession() ASI (discussed further in using the openSession() ASI (discussed further in
Section 5.3.1). Implementations MAY wish to offer message Section 5.3.1). Implementations MAY wish to offer message
buffering to prevent redundant openSession() calls for the buffering to prevent redundant openSession() calls for the
same cache entry. If an error is returned from same cache entry. If an error is returned from
openSession(), then discard the message, discard the openSession(), then discard the message, discard the
tmStateReference, increment the snmpTlstmSessionOpenErrors, tmStateReference, increment the snmpTlstmSessionOpenErrors,
return an error indication to the calling module and stop return an error indication to the calling module, and stop
processing of the message. the processing of the message.
6) Using either the session indicated by the tmSessionID if there 6) Using either the session indicated by the tmSessionID (if there
was one or the session resulting from a previous step (4 or 5), was one) or the session resulting from a previous step (4 or 5),
pass the outgoingMessage to (D)TLS for encapsulation and pass the outgoingMessage to (D)TLS for encapsulation and
transmission. transmission.
5.3. Establishing or Accepting a Session 5.3. Establishing or Accepting a Session
Establishing a (D)TLS connection as either a client or a server Establishing a (D)TLS connection as either a client or a server
requires slightly different processing. The following two sections requires slightly different processing. The following two sections
describe the necessary processing steps. describe the necessary processing steps.
5.3.1. Establishing a Session as a Client 5.3.1. Establishing a Session as a Client
skipping to change at page 26, line 28 skipping to change at page 25, line 41
The TLS Transport Model provides the following primitive for use by a The TLS Transport Model provides the following primitive for use by a
client to establish a new (D)TLS connection: client to establish a new (D)TLS connection:
statusInformation = -- errorIndication or success statusInformation = -- errorIndication or success
openSession( openSession(
IN tmStateReference -- transport information to be used IN tmStateReference -- transport information to be used
OUT tmStateReference -- transport information to be used OUT tmStateReference -- transport information to be used
IN maxMessageSize -- of the sending SNMP entity IN maxMessageSize -- of the sending SNMP entity
) )
The following describes the procedure to follow when establishing a The following describes the procedure to follow when establishing an
SNMP over (D)TLS connection between SNMP engines for exchanging SNMP SNMP over a (D)TLS connection between SNMP engines for exchanging
messages. This process is followed by any SNMP client's engine when SNMP messages. This process is followed by any SNMP client's engine
establishing a session for subsequent use. when establishing a session for subsequent use.
This procedure MAY be done automatically for an SNMP application that This procedure MAY be done automatically for an SNMP application that
initiates a transaction, such as a command generator, a notification initiates a transaction, such as a command generator, a notification
originator, or a proxy forwarder. originator, or a proxy forwarder.
1) The snmpTlstmSessionOpens counter is incremented. 1) The snmpTlstmSessionOpens counter is incremented.
2) The client selects the appropriate certificate and cipher_suites 2) The client selects the appropriate certificate and cipher_suites
for the key agreement based on the tmSecurityName and the for the key agreement based on the tmSecurityName and the
tmRequestedSecurityLevel for the session. For sessions being tmRequestedSecurityLevel for the session. For sessions being
established as a result of a SNMP-TARGET-MIB based operation, the established as a result of an SNMP-TARGET-MIB based operation,
certificate will potentially have been identified via the the certificate will potentially have been identified via the
snmpTlstmParamsTable mapping and the cipher_suites will have to snmpTlstmParamsTable mapping and the cipher_suites will have to
be taken from system-wide or implementation-specific be taken from a system-wide or implementation-specific
configuration. If no row in the snmpTlstmParamsTable exists then configuration. If no row in the snmpTlstmParamsTable exists,
implementations MAY choose to establish the connection using a then implementations MAY choose to establish the connection using
default client certificate available to the application. a default client certificate available to the application.
Otherwise, the certificate and appropriate cipher_suites will Otherwise, the certificate and appropriate cipher_suites will
need to be passed to the openSession() ASI as supplemental need to be passed to the openSession() ASI as supplemental
information or configured through an implementation-dependent information or configured through an implementation-dependent
mechanism. It is also implementation-dependent and possibly mechanism. It is also implementation-dependent and possibly
policy-dependent how tmRequestedSecurityLevel will be used to policy-dependent how tmRequestedSecurityLevel will be used to
influence the security capabilities provided by the (D)TLS influence the security capabilities provided by the (D)TLS
connection. However this is done, the security capabilities connection. However this is done, the security capabilities
provided by (D)TLS MUST be at least as high as the level of provided by (D)TLS MUST be at least as high as the level of
security indicated by the tmRequestedSecurityLevel parameter. security indicated by the tmRequestedSecurityLevel parameter.
The actual security level of the session is reported in the The actual security level of the session is reported in the
skipping to change at page 27, line 22 skipping to change at page 26, line 36
strong authentication, each principal acting as a command strong authentication, each principal acting as a command
generator SHOULD have its own certificate. generator SHOULD have its own certificate.
3) Using the destTransportDomain and destTransportAddress values, 3) Using the destTransportDomain and destTransportAddress values,
the client will initiate the (D)TLS handshake protocol to the client will initiate the (D)TLS handshake protocol to
establish session keys for message integrity and encryption. establish session keys for message integrity and encryption.
If the attempt to establish a session is unsuccessful, then If the attempt to establish a session is unsuccessful, then
snmpTlstmSessionOpenErrors is incremented, an error indication is snmpTlstmSessionOpenErrors is incremented, an error indication is
returned, and processing stops. If the session failed to open returned, and processing stops. If the session failed to open
because the presented server certificate was unknown or invalid because the presented server certificate was unknown or invalid,
then the snmpTlstmSessionUnknownServerCertificate or then the snmpTlstmSessionUnknownServerCertificate or
snmpTlstmSessionInvalidServerCertificates MUST be incremented and snmpTlstmSessionInvalidServerCertificates MUST be incremented and
a snmpTlstmServerCertificateUnknown or an snmpTlstmServerCertificateUnknown or
snmpTlstmServerInvalidCertificate notification SHOULD be sent as snmpTlstmServerInvalidCertificate notification SHOULD be sent as
appropriate. Reasons for server certificate invalidation appropriate. Reasons for server certificate invalidation
includes, but is not limited to, cryptographic validation includes, but is not limited to, cryptographic validation
failures and an unexpected presented certificate identity. failures and an unexpected presented certificate identity.
4) The (D)TLS client MUST then verify that the (D)TLS server's 4) The (D)TLS client MUST then verify that the (D)TLS server's
presented certificate is the expected certificate. The (D)TLS presented certificate is the expected certificate. The (D)TLS
client MUST NOT transmit SNMP messages until the server client MUST NOT transmit SNMP messages until the server
certificate has been authenticated, the client certificate has certificate has been authenticated, the client certificate has
been transmitted and the TLS connection has been fully been transmitted and the TLS connection has been fully
established. established.
If the connection is being established from configuration based If the connection is being established from a configuration based
on SNMP-TARGET-MIB configuration, then the snmpTlstmAddrTable on SNMP-TARGET-MIB configuration, then the snmpTlstmAddrTable
DESCRIPTION clause describes how the verification is done (using DESCRIPTION clause describes how the verification is done (using
either a certificate fingerprint, or an identity authenticated either a certificate fingerprint, or an identity authenticated
via certification path validation). via certification path validation).
If the connection is being established for reasons other than If the connection is being established for reasons other than
configuration found in the SNMP-TARGET-MIB then configuration and configuration found in the SNMP-TARGET-MIB, then configuration
procedures outside the scope of this document should be followed. and procedures outside the scope of this document should be
Configuration mechanisms SHOULD be similar in nature to those followed. Configuration mechanisms SHOULD be similar in nature
defined in the snmpTlstmAddrTable to ensure consistency across to those defined in the snmpTlstmAddrTable to ensure consistency
management configuration systems. For example, a command-line across management configuration systems. For example, a command-
tool for generating SNMP GETs might support specifying either the line tool for generating SNMP GETs might support specifying
server's certificate fingerprint or the expected host name as a either the server's certificate fingerprint or the expected host
command line argument. name as a command-line argument.
5) (D)TLS provides assurance that the authenticated identity has 5) (D)TLS provides assurance that the authenticated identity has
been signed by a trusted configured certification authority. If been signed by a trusted configured Certification Authority. If
verification of the server's certificate fails in any way (for verification of the server's certificate fails in any way (for
example because of failures in cryptographic verification or the example, because of failures in cryptographic verification or the
presented identity did not match the expected named entity) then presented identity did not match the expected named entity) then
the session establishment MUST fail, the the session establishment MUST fail, the
snmpTlstmSessionInvalidServerCertificates object is incremented. snmpTlstmSessionInvalidServerCertificates object is incremented.
If the session can not be opened for any reason at all, including If the session cannot be opened for any reason at all, including
cryptographic verification failures and snmpTlstmCertToTSNTable cryptographic verification failures and snmpTlstmCertToTSNTable
lookup failures, then the snmpTlstmSessionOpenErrors counter is lookup failures, then the snmpTlstmSessionOpenErrors counter is
incremented and processing stops. incremented and processing stops.
6) The TLSTM-specific session identifier (tlstmSessionID) is set in 6) The TLSTM-specific session identifier (tlstmSessionID) is set in
the tmSessionID of the tmStateReference passed to the TLS the tmSessionID of the tmStateReference passed to the TLS
Transport Model to indicate that the session has been established Transport Model to indicate that the session has been established
successfully and to point to a specific (D)TLS connection for successfully and to point to a specific (D)TLS connection for
future use. The tlstmSessionID is also stored in the LCD for future use. The tlstmSessionID is also stored in the LCD for
later lookup during processing of incoming messages later lookup during processing of incoming messages
(Section 5.1.2). (Section 5.1.2).
5.3.2. Accepting a Session as a Server 5.3.2. Accepting a Session as a Server
A (D)TLS server should accept new session connections from any client A (D)TLS server should accept new session connections from any client
that it is able to verify the client's credentials for. This is done for which it is able to verify the client's credentials. This is
by authenticating the client's presented certificate through a done by authenticating the client's presented certificate through a
certificate path validation process (e.g. [RFC5280]) or through certificate path validation process (e.g., [RFC5280]) or through
certificate fingerprint verification using fingerprints configured in certificate fingerprint verification using fingerprints configured in
the snmpTlstmCertToTSNTable. Afterward the server will determine the the snmpTlstmCertToTSNTable. Afterward, the server will determine
identity of the remote entity using the following procedures. the identity of the remote entity using the following procedures.
The (D)TLS server identifies the authenticated identity from the The (D)TLS server identifies the authenticated identity from the
(D)TLS client's principal certificate using configuration information (D)TLS client's principal certificate using configuration information
from the snmpTlstmCertToTSNTable mapping table. The (D)TLS server from the snmpTlstmCertToTSNTable mapping table. The (D)TLS server
MUST request and expect a certificate from the client and MUST NOT MUST request and expect a certificate from the client and MUST NOT
accept SNMP messages over the (D)TLS connection until the client has accept SNMP messages over the (D)TLS connection until the client has
sent a certificate and it has been authenticated. The resulting sent a certificate and it has been authenticated. The resulting
derived tmSecurityName is recorded in the tmStateReference cache as derived tmSecurityName is recorded in the tmStateReference cache as
tmSecurityName. The details of the lookup process are fully tmSecurityName. The details of the lookup process are fully
described in the DESCRIPTION clause of the snmpTlstmCertToTSNTable described in the DESCRIPTION clause of the snmpTlstmCertToTSNTable
MIB object. If any verification fails in any way (for example MIB object. If any verification fails in any way (for example,
because of failures in cryptographic verification or because of the because of failures in cryptographic verification or because of the
lack of an appropriate row in the snmpTlstmCertToTSNTable) then the lack of an appropriate row in the snmpTlstmCertToTSNTable), then the
session establishment MUST fail, and the session establishment MUST fail, and the
snmpTlstmSessionInvalidClientCertificates object is incremented. If snmpTlstmSessionInvalidClientCertificates object is incremented. If
the session can not be opened for any reason at all, including the session cannot be opened for any reason at all, including
cryptographic verification failures, then the cryptographic verification failures, then the
snmpTlstmSessionOpenErrors counter is incremented and processing snmpTlstmSessionOpenErrors counter is incremented and processing
stops. stops.
Servers that wish to support multiple principals at a particular port Servers that wish to support multiple principals at a particular port
SHOULD make use of a (D)TLS extension that allows server-side SHOULD make use of a (D)TLS extension that allows server-side
principal selection like the Server Name Indication extension defined principal selection like the Server Name Indication extension defined
in Section 3.1 of [RFC4366]. Supporting this will allow, for in Section 3.1 of [RFC4366]. Supporting this will allow, for
example, sending notifications to a specific principal at a given TCP example, sending notifications to a specific principal at a given TCP
or UDP port. or UDP port.
skipping to change at page 29, line 44 skipping to change at page 29, line 13
closeSession processing is completed. closeSession processing is completed.
4) Have (D)TLS close the specified connection. This MUST include 4) Have (D)TLS close the specified connection. This MUST include
sending a close_notify TLS Alert to inform the other side that sending a close_notify TLS Alert to inform the other side that
session cleanup may be performed. session cleanup may be performed.
6. MIB Module Overview 6. MIB Module Overview
This MIB module provides management of the TLS Transport Model. It This MIB module provides management of the TLS Transport Model. It
defines needed textual conventions, statistical counters, defines needed textual conventions, statistical counters,
notifications and configuration infrastructure necessary for session notifications, and configuration infrastructure necessary for session
establishment. Example usage of the configuration tables can be establishment. Example usage of the configuration tables can be
found in Appendix A. found in Appendix A.
6.1. Structure of the MIB Module 6.1. Structure of the MIB Module
Objects in this MIB module are arranged into subtrees. Each subtree Objects in this MIB module are arranged into subtrees. Each subtree
is organized as a set of related objects. The overall structure and is organized as a set of related objects. The overall structure and
assignment of objects to their subtrees, and the intended purpose of assignment of objects to their subtrees, and the intended purpose of
each subtree, is shown below. each subtree, is shown below.
6.2. Textual Conventions 6.2. Textual Conventions
Generic and Common Textual Conventions used in this module can be Generic and Common Textual Conventions used in this module can be
found summarized at http://www.ops.ietf.org/mib-common-tcs.html found summarized at http://www.ops.ietf.org/mib-common-tcs.html.
This module defines the following new Textual Conventions: This module defines the following new Textual Conventions:
o A new TransportAddress format for describing (D)TLS connection o A new TransportAddress format for describing (D)TLS connection
addressing requirements. addressing requirements.
o A certificate fingerprint allowing MIB module objects to o A certificate fingerprint allowing MIB module objects to
generically refer to a stored X.509 certificate using a generically refer to a stored X.509 certificate using a
cryptographic hash as a reference pointer. cryptographic hash as a reference pointer.
skipping to change at page 30, line 39 skipping to change at page 29, line 51
stations with information about session usage and potential errors stations with information about session usage and potential errors
that a device may be experiencing. that a device may be experiencing.
6.4. Configuration Tables 6.4. Configuration Tables
The SNMP-TLS-TM-MIB defines configuration tables that an The SNMP-TLS-TM-MIB defines configuration tables that an
administrator can use for configuring a device for sending and administrator can use for configuring a device for sending and
receiving SNMP messages over (D)TLS. In particular, there are MIB receiving SNMP messages over (D)TLS. In particular, there are MIB
tables that extend the SNMP-TARGET-MIB for configuring (D)TLS tables that extend the SNMP-TARGET-MIB for configuring (D)TLS
certificate usage and a MIB table for mapping incoming (D)TLS client certificate usage and a MIB table for mapping incoming (D)TLS client
certificates to SNMPv3 securityNames. certificates to SNMPv3 tmSecurityNames.
6.4.1. Notifications 6.4.1. Notifications
The SNMP-TLS-TM-MIB defines notifications to alert management The SNMP-TLS-TM-MIB defines notifications to alert management
stations when a (D)TLS connection fails because a server's presented stations when a (D)TLS connection fails because a server's presented
certificate did not meet an expected value certificate did not meet an expected value
(snmpTlstmServerCertificateUnknown) or because cryptographic (snmpTlstmServerCertificateUnknown) or because cryptographic
validation failed (snmpTlstmServerInvalidCertificate). validation failed (snmpTlstmServerInvalidCertificate).
6.5. Relationship to Other MIB Modules 6.5. Relationship to Other MIB Modules
Some management objects defined in other MIB modules are applicable Some management objects defined in other MIB modules are applicable
to an entity implementing the TLS Transport Model. In particular, it to an entity implementing the TLS Transport Model. In particular, it
is assumed that an entity implementing the SNMP-TLS-TM-MIB will is assumed that an entity implementing the SNMP-TLS-TM-MIB will
implement the SNMPv2-MIB [RFC3418], the SNMP-FRAMEWORK-MIB [RFC3411], implement the SNMPv2-MIB [RFC3418], the SNMP-FRAMEWORK-MIB [RFC3411],
the SNMP-TARGET-MIB [RFC3413], the SNMP-NOTIFICATION-MIB [RFC3413] the SNMP-TARGET-MIB [RFC3413], the SNMP-NOTIFICATION-MIB [RFC3413],
and the SNMP-VIEW-BASED-ACM-MIB [RFC3415]. and the SNMP-VIEW-BASED-ACM-MIB [RFC3415].
The SNMP-TLS-TM-MIB module contained in this document is for managing The SNMP-TLS-TM-MIB module contained in this document is for managing
TLS Transport Model information. TLS Transport Model information.
6.5.1. MIB Modules Required for IMPORTS 6.5.1. MIB Modules Required for IMPORTS
The SNMP-TLS-TM-MIB module imports items from SNMPv2-SMI [RFC2578], The SNMP-TLS-TM-MIB module imports items from SNMPv2-SMI [RFC2578],
SNMPv2-TC [RFC2579], SNMP-FRAMEWORK-MIB [RFC3411], SNMP-TARGET-MIB SNMPv2-TC [RFC2579], SNMP-FRAMEWORK-MIB [RFC3411], SNMP-TARGET-MIB
[RFC3413] and SNMPv2-CONF [RFC2580]. [RFC3413], and SNMPv2-CONF [RFC2580].
7. MIB Module Definition 7. MIB Module Definition
SNMP-TLS-TM-MIB DEFINITIONS ::= BEGIN SNMP-TLS-TM-MIB DEFINITIONS ::= BEGIN
IMPORTS IMPORTS
MODULE-IDENTITY, OBJECT-TYPE, MODULE-IDENTITY, OBJECT-TYPE,
OBJECT-IDENTITY, mib-2, snmpDomains, OBJECT-IDENTITY, mib-2, snmpDomains,
Counter32, Unsigned32, Gauge32, NOTIFICATION-TYPE Counter32, Unsigned32, Gauge32, NOTIFICATION-TYPE
FROM SNMPv2-SMI -- RFC2578 or any update thereof FROM SNMPv2-SMI -- RFC 2578 or any update thereof
TEXTUAL-CONVENTION, TimeStamp, RowStatus, StorageType, TEXTUAL-CONVENTION, TimeStamp, RowStatus, StorageType,
AutonomousType AutonomousType
FROM SNMPv2-TC -- RFC2579 or any update thereof FROM SNMPv2-TC -- RFC 2579 or any update thereof
MODULE-COMPLIANCE, OBJECT-GROUP, NOTIFICATION-GROUP MODULE-COMPLIANCE, OBJECT-GROUP, NOTIFICATION-GROUP
FROM SNMPv2-CONF -- RFC2580 or any update thereof FROM SNMPv2-CONF -- RFC 2580 or any update thereof
SnmpAdminString SnmpAdminString
FROM SNMP-FRAMEWORK-MIB -- RFC3411 or any update thereof FROM SNMP-FRAMEWORK-MIB -- RFC 3411 or any update thereof
snmpTargetParamsName, snmpTargetAddrName snmpTargetParamsName, snmpTargetAddrName
FROM SNMP-TARGET-MIB -- RFC3413 or any update thereof FROM SNMP-TARGET-MIB -- RFC 3413 or any update thereof
; ;
snmpTlstmMIB MODULE-IDENTITY snmpTlstmMIB MODULE-IDENTITY
LAST-UPDATED "201005070000Z" LAST-UPDATED "201005070000Z"
ORGANIZATION "ISMS Working Group" ORGANIZATION "ISMS Working Group"
CONTACT-INFO "WG-EMail: isms@lists.ietf.org CONTACT-INFO "WG-EMail: isms@lists.ietf.org
Subscribe: isms-request@lists.ietf.org Subscribe: isms-request@lists.ietf.org
Chairs: Chairs:
Juergen Schoenwaelder Juergen Schoenwaelder
skipping to change at page 32, line 15 skipping to change at page 31, line 28
j.schoenwaelder@jacobs-university.de j.schoenwaelder@jacobs-university.de
Russ Mundy Russ Mundy
SPARTA, Inc. SPARTA, Inc.
7110 Samuel Morse Drive 7110 Samuel Morse Drive
Columbia, MD 21046 Columbia, MD 21046
USA USA
Editor: Editor:
Wes Hardaker Wes Hardaker
Sparta, Inc. SPARTA, Inc.
P.O. Box 382 P.O. Box 382
Davis, CA 95617 Davis, CA 95617
USA USA
ietf@hardakers.net ietf@hardakers.net
" "
DESCRIPTION " DESCRIPTION "
The TLS Transport Model MIB The TLS Transport Model MIB
Copyright (c) 2010 IETF Trust and the persons identified as Copyright (c) 2010 IETF Trust and the persons identified as
skipping to change at page 32, line 37 skipping to change at page 31, line 50
Redistribution and use in source and binary forms, with or Redistribution and use in source and binary forms, with or
without modification, is permitted pursuant to, and subject without modification, is permitted pursuant to, and subject
to the license terms contained in, the Simplified BSD License to the license terms contained in, the Simplified BSD License
set forth in Section 4.c of the IETF Trust's Legal Provisions set forth in Section 4.c of the IETF Trust's Legal Provisions
Relating to IETF Documents Relating to IETF Documents
(http://trustee.ietf.org/license-info)." (http://trustee.ietf.org/license-info)."
REVISION "201005070000Z" REVISION "201005070000Z"
DESCRIPTION "This version of this MIB module is part of DESCRIPTION "This version of this MIB module is part of
RFC XXXX; see the RFC itself for full legal RFC 5953; see the RFC itself for full legal
notices." notices."
::= { mib-2 198 }
::= { mib-2 www }
-- ************************************************ -- ************************************************
-- subtrees of the SNMP-TLS-TM-MIB -- subtrees of the SNMP-TLS-TM-MIB
-- ************************************************ -- ************************************************
snmpTlstmNotifications OBJECT IDENTIFIER ::= { snmpTlstmMIB 0 } snmpTlstmNotifications OBJECT IDENTIFIER ::= { snmpTlstmMIB 0 }
snmpTlstmIdentities OBJECT IDENTIFIER ::= { snmpTlstmMIB 1 } snmpTlstmIdentities OBJECT IDENTIFIER ::= { snmpTlstmMIB 1 }
snmpTlstmObjects OBJECT IDENTIFIER ::= { snmpTlstmMIB 2 } snmpTlstmObjects OBJECT IDENTIFIER ::= { snmpTlstmMIB 2 }
snmpTlstmConformance OBJECT IDENTIFIER ::= { snmpTlstmMIB 3 } snmpTlstmConformance OBJECT IDENTIFIER ::= { snmpTlstmMIB 3 }
-- ************************************************ -- ************************************************
-- snmpTlstmObjects - Objects -- snmpTlstmObjects - Objects
-- ************************************************ -- ************************************************
snmpTLSTCPDomain OBJECT-IDENTITY snmpTLSTCPDomain OBJECT-IDENTITY
skipping to change at page 33, line 16 skipping to change at page 32, line 23
snmpTlstmObjects OBJECT IDENTIFIER ::= { snmpTlstmMIB 2 } snmpTlstmObjects OBJECT IDENTIFIER ::= { snmpTlstmMIB 2 }
snmpTlstmConformance OBJECT IDENTIFIER ::= { snmpTlstmMIB 3 } snmpTlstmConformance OBJECT IDENTIFIER ::= { snmpTlstmMIB 3 }
-- ************************************************ -- ************************************************
-- snmpTlstmObjects - Objects -- snmpTlstmObjects - Objects
-- ************************************************ -- ************************************************
snmpTLSTCPDomain OBJECT-IDENTITY snmpTLSTCPDomain OBJECT-IDENTITY
STATUS current STATUS current
DESCRIPTION DESCRIPTION
"The SNMP over TLS transport domain. The corresponding "The SNMP over TLS via TCP transport domain. The
transport address is of type SnmpTLSAddress. corresponding transport address is of type SnmpTLSAddress.
The securityName prefix to be associated with the The securityName prefix to be associated with the
snmpTLSTCPDomain is 'tls'. This prefix may be used by snmpTLSTCPDomain is 'tls'. This prefix may be used by
security models or other components to identify which secure security models or other components to identify which secure
transport infrastructure authenticated a securityName." transport infrastructure authenticated a securityName."
REFERENCE REFERENCE
"RFC 2579: Textual Conventions for SMIv2" "RFC 2579: Textual Conventions for SMIv2"
::= { snmpDomains xx } ::= { snmpDomains 8 }
snmpDTLSUDPDomain OBJECT-IDENTITY snmpDTLSUDPDomain OBJECT-IDENTITY
STATUS current STATUS current
DESCRIPTION DESCRIPTION
"The SNMP over DTLS/UDP transport domain. The corresponding "The SNMP over DTLS via UDP transport domain. The
transport address is of type SnmpTLSAddress. corresponding transport address is of type SnmpTLSAddress.
The securityName prefix to be associated with the The securityName prefix to be associated with the
snmpDTLSUDPDomain is 'dtls'. This prefix may be used by snmpDTLSUDPDomain is 'dtls'. This prefix may be used by
security models or other components to identify which secure security models or other components to identify which secure
transport infrastructure authenticated a securityName." transport infrastructure authenticated a securityName."
REFERENCE REFERENCE
"RFC 2579: Textual Conventions for SMIv2" "RFC 2579: Textual Conventions for SMIv2"
::= { snmpDomains yy } ::= { snmpDomains 9 }
SnmpTLSAddress ::= TEXTUAL-CONVENTION SnmpTLSAddress ::= TEXTUAL-CONVENTION
DISPLAY-HINT "1a" DISPLAY-HINT "1a"
STATUS current STATUS current
DESCRIPTION DESCRIPTION
"Represents a IPv4 address, an IPv6 address or an US-ASCII "Represents an IPv4 address, an IPv6 address, or a
encoded hostname and port number. US-ASCII-encoded hostname and port number.
An IPv4 address must be in dotted decimal format followed by a An IPv4 address must be in dotted decimal format followed by a
colon ':' (US-ASCII character 0x3A) and a decimal port number colon ':' (US-ASCII character 0x3A) and a decimal port number
in US-ASCII. in US-ASCII.
An IPv6 address must be a colon separated format (as described An IPv6 address must be a colon-separated format (as described
in I-D.ietf-6man-text-addr-representation), surrounded by in RFC 5952), surrounded by square brackets ('[', US-ASCII
square brackets ('[', US-ASCII character 0x5B, and ']', character 0x5B, and ']', US-ASCII character 0x5D), followed by
US-ASCII character 0x5D), followed by a colon ':' (US-ASCII a colon ':' (US-ASCII character 0x3A) and a decimal port number
character 0x3A) and a decimal port number in US-ASCII. in US-ASCII.
A hostname is always in US-ASCII (as per RFC1033); A hostname is always in US-ASCII (as per [RFC1033]);
internationalized hostnames are encoded in US-ASCII as domain internationalized hostnames are encoded in US-ASCII as domain
names after transformation via the ToASCII operation specified names after transformation via the ToASCII operation specified
in RFC 3490. The ToASCII operation MUST be performed with the in [RFC3490]. The ToASCII operation MUST be performed with the
UseSTD3ASCIIRules flag set. The hostname is followed by a UseSTD3ASCIIRules flag set. The hostname is followed by a
colon ':' (US-ASCII character 0x3A) and a decimal port number colon ':' (US-ASCII character 0x3A) and a decimal port number
in US-ASCII. The name SHOULD be fully qualified whenever in US-ASCII. The name SHOULD be fully qualified whenever
possible. possible.
Values of this textual convention may not be directly usable Values of this textual convention may not be directly usable
as transport-layer addressing information, and may require as transport-layer addressing information, and may require
run-time resolution. As such, applications that write them run-time resolution. As such, applications that write them
must be prepared for handling errors if such values are not must be prepared for handling errors if such values are not
supported, or cannot be resolved (if resolution occurs at the supported, or cannot be resolved (if resolution occurs at the
skipping to change at page 35, line 14 skipping to change at page 34, line 9
When this textual convention is used as a syntax of an index When this textual convention is used as a syntax of an index
object, there may be issues with the limit of 128 object, there may be issues with the limit of 128
sub-identifiers specified in SMIv2 (STD 58). It is RECOMMENDED sub-identifiers specified in SMIv2 (STD 58). It is RECOMMENDED
that all MIB documents using this textual convention make that all MIB documents using this textual convention make
explicit any limitations on index component lengths that explicit any limitations on index component lengths that
management software must observe. This may be done either by management software must observe. This may be done either by
including SIZE constraints on the index components or by including SIZE constraints on the index components or by
specifying applicable constraints in the conceptual row specifying applicable constraints in the conceptual row
DESCRIPTION clause or in the surrounding documentation." DESCRIPTION clause or in the surrounding documentation."
REFERENCE REFERENCE
"RFC 1033: DOMAIN ADMINISTRATORS OPERATIONS GUIDE "RFC 1033: DOMAIN ADMINISTRATORS OPERATIONS GUIDE
RFC 3490: Internationalizing Domain Names in Applications RFC 3490: Internationalizing Domain Names in Applications
I-D.ietf-6man-text-addr-representation: RFC 5952: A Recommendation for IPv6 Address Text Representation
A Recommendation for IPv6 Address Text Representation
" "
SYNTAX OCTET STRING (SIZE (1..255)) SYNTAX OCTET STRING (SIZE (1..255))
SnmpTLSFingerprint ::= TEXTUAL-CONVENTION SnmpTLSFingerprint ::= TEXTUAL-CONVENTION
DISPLAY-HINT "1x:254x" DISPLAY-HINT "1x:1x"
STATUS current STATUS current
DESCRIPTION DESCRIPTION
"A fingerprint value that can be used to uniquely reference "A fingerprint value that can be used to uniquely reference
other data of potentially arbitrary length. other data of potentially arbitrary length.
A SnmpTLSFingerprint value is composed of a 1-octet hashing An SnmpTLSFingerprint value is composed of a 1-octet hashing
algorithm identifier followed by the fingerprint value. The algorithm identifier followed by the fingerprint value. The
octet value encoded is taken from the IANA TLS HashAlgorithm octet value encoded is taken from the IANA TLS HashAlgorithm
Registry (RFC5246). The remaining octets are filled using the Registry (RFC 5246). The remaining octets are filled using the
results of the hashing algorithm. results of the hashing algorithm.
This TEXTUAL-CONVENTION allows for a zero-length (blank) This TEXTUAL-CONVENTION allows for a zero-length (blank)
SnmpTLSFingerprint value for use in tables where the SnmpTLSFingerprint value for use in tables where the
fingerprint value may be optional. MIB definitions or fingerprint value may be optional. MIB definitions or
implementations may refuse to accept a zero-length value as implementations may refuse to accept a zero-length value as
appropriate." appropriate."
REFERENCE "RFC 5246: The Transport Layer REFERENCE "RFC 5246: The Transport Layer
Security (TLS) Protocol Version 1.2 Security (TLS) Protocol Version 1.2
http://www.iana.org/assignments/tls-parameters/ http://www.iana.org/assignments/tls-parameters/
" "
SYNTAX OCTET STRING (SIZE (0..255)) SYNTAX OCTET STRING (SIZE (0..255))
-- Identities for use in the snmpTlstmCertToTSNTable -- Identities for use in the snmpTlstmCertToTSNTable
snmpTlstmCertToTSNMIdentities OBJECT IDENTIFIER snmpTlstmCertToTSNMIdentities OBJECT IDENTIFIER
::= { snmpTlstmIdentities 1 } ::= { snmpTlstmIdentities 1 }
snmpTlstmCertSpecified OBJECT-IDENTITY snmpTlstmCertSpecified OBJECT-IDENTITY
STATUS current STATUS current
DESCRIPTION "Directly specifies the tmSecurityName to be used for DESCRIPTION "Directly specifies the tmSecurityName to be used for
this certificate. The value of the tmSecurityName this certificate. The value of the tmSecurityName
to use is specified in the snmpTlstmCertToTSNData to use is specified in the snmpTlstmCertToTSNData
column. The snmpTlstmCertToTSNData column must column. The snmpTlstmCertToTSNData column must
contain a non-zero length SnmpAdminString compliant contain a non-zero length SnmpAdminString compliant
skipping to change at page 36, line 23 skipping to change at page 35, line 14
contain a non-zero length SnmpAdminString compliant contain a non-zero length SnmpAdminString compliant
value or the mapping described in this row must be value or the mapping described in this row must be
considered a failure." considered a failure."
::= { snmpTlstmCertToTSNMIdentities 1 } ::= { snmpTlstmCertToTSNMIdentities 1 }
snmpTlstmCertSANRFC822Name OBJECT-IDENTITY snmpTlstmCertSANRFC822Name OBJECT-IDENTITY
STATUS current STATUS current
DESCRIPTION "Maps a subjectAltName's rfc822Name to a DESCRIPTION "Maps a subjectAltName's rfc822Name to a
tmSecurityName. The local part of the rfc822Name is tmSecurityName. The local part of the rfc822Name is
passed unaltered but the host-part of the name must passed unaltered but the host-part of the name must
be passed in lower case. This mapping results in a be passed in lowercase. This mapping results in a
1:1 correspondence between equivalent subjectAltName 1:1 correspondence between equivalent subjectAltName
rfc822Name values and tmSecurityName values except rfc822Name values and tmSecurityName values except
that the host-part of the name MUST be passed in that the host-part of the name MUST be passed in
lower case. lowercase.
Example rfc822Name Field: FooBar@Example.COM Example rfc822Name Field: FooBar@Example.COM
is mapped to tmSecurityName: FooBar@example.com" is mapped to tmSecurityName: FooBar@example.com."
::= { snmpTlstmCertToTSNMIdentities 2 } ::= { snmpTlstmCertToTSNMIdentities 2 }
snmpTlstmCertSANDNSName OBJECT-IDENTITY snmpTlstmCertSANDNSName OBJECT-IDENTITY
STATUS current STATUS current
DESCRIPTION "Maps a subjectAltName's dNSName to a DESCRIPTION "Maps a subjectAltName's dNSName to a
tmSecurityName after first converting it to all tmSecurityName after first converting it to all
lower case (RFC5280 does not specify converting to lowercase (RFC 5280 does not specify converting to
lower case so this involves an extra step). This lowercase so this involves an extra step). This
mapping results in a 1:1 correspondence between mapping results in a 1:1 correspondence between
subjectAltName dNSName values and the tmSecurityName subjectAltName dNSName values and the tmSecurityName
values." values."
REFERENCE "RFC5280 - Internet X.509 Public Key Infrastructure REFERENCE "RFC 5280 - Internet X.509 Public Key Infrastructure
Certificate and Certificate Revocation Certificate and Certificate Revocation
List (CRL) Profile" List (CRL) Profile."
::= { snmpTlstmCertToTSNMIdentities 3 } ::= { snmpTlstmCertToTSNMIdentities 3 }
snmpTlstmCertSANIpAddress OBJECT-IDENTITY snmpTlstmCertSANIpAddress OBJECT-IDENTITY
STATUS current STATUS current
DESCRIPTION "Maps a subjectAltName's iPAddress to a DESCRIPTION "Maps a subjectAltName's iPAddress to a
tmSecurityName by transforming the binary encoded tmSecurityName by transforming the binary encoded
address as follows: address as follows:
1) for IPv4 the value is converted into a decimal 1) for IPv4, the value is converted into a
dotted quad address (e.g. '192.0.2.1') decimal-dotted quad address (e.g., '192.0.2.1').
2) for IPv6 addresses the value is converted into a 2) for IPv6 addresses, the value is converted into a
32-character all lowercase hexadecimal string 32-character all lowercase hexadecimal string
without any colon separators. without any colon separators.
This mapping results in a 1:1 correspondence between This mapping results in a 1:1 correspondence between
subjectAltName iPAddress values and the subjectAltName iPAddress values and the
tmSecurityName values. tmSecurityName values.
The resulting length is the maximum length supported The resulting length of an encoded IPv6 address is
by the View-Based Access Control Model (VACM). the maximum length supported by the View-Based
Using both the Transport Security Model's support Access Control Model (VACM). Using both the
for transport prefixes (see the SNMP-TSM-MIB's Transport Security Model's support for transport
prefixes (see the SNMP-TSM-MIB's
snmpTsmConfigurationUsePrefix object for details) snmpTsmConfigurationUsePrefix object for details)
will result in securityName lengths that exceed what will result in securityName lengths that exceed what
VACM can handle." VACM can handle."
::= { snmpTlstmCertToTSNMIdentities 4 } ::= { snmpTlstmCertToTSNMIdentities 4 }
snmpTlstmCertSANAny OBJECT-IDENTITY snmpTlstmCertSANAny OBJECT-IDENTITY
STATUS current STATUS current
DESCRIPTION "Maps any of the following fields using the DESCRIPTION "Maps any of the following fields using the
corresponding mapping algorithms: corresponding mapping algorithms:
skipping to change at page 37, line 45 skipping to change at page 36, line 39
| iPAddress | snmpTlstmCertSANIpAddress | | iPAddress | snmpTlstmCertSANIpAddress |
|------------+----------------------------| |------------+----------------------------|
The first matching subjectAltName value found in the The first matching subjectAltName value found in the
certificate of the above types MUST be used when certificate of the above types MUST be used when
deriving the tmSecurityName. The mapping algorithm deriving the tmSecurityName. The mapping algorithm
specified in the 'Algorithm' column MUST be used to specified in the 'Algorithm' column MUST be used to
derive the tmSecurityName. derive the tmSecurityName.
This mapping results in a 1:1 correspondence between This mapping results in a 1:1 correspondence between
subjectAltName values and tmSecurityName values. The subjectAltName values and tmSecurityName values. The
three sub-mapping algorithms produced by this three sub-mapping algorithms produced by this
combined algorithm cannot produce conflicting combined algorithm cannot produce conflicting
results between themselves." results between themselves."
::= { snmpTlstmCertToTSNMIdentities 5 } ::= { snmpTlstmCertToTSNMIdentities 5 }
snmpTlstmCertCommonName OBJECT-IDENTITY snmpTlstmCertCommonName OBJECT-IDENTITY
STATUS current STATUS current
DESCRIPTION "Maps a certificate's CommonName to a tmSecurityName DESCRIPTION "Maps a certificate's CommonName to a tmSecurityName
after converting it to a UTF-8 encoding. The usage after converting it to a UTF-8 encoding. The usage
of CommonNames is deprecated and users are of CommonNames is deprecated and users are
encouraged to use subjectAltName mapping methods encouraged to use subjectAltName mapping methods
instead. This mapping results in a 1:1 instead. This mapping results in a 1:1
correspondence between certificate CommonName values correspondence between certificate CommonName values
and tmSecurityName values." and tmSecurityName values."
::= { snmpTlstmCertToTSNMIdentities 6 } ::= { snmpTlstmCertToTSNMIdentities 6 }
-- The snmpTlstmSession Group -- The snmpTlstmSession Group
skipping to change at page 38, line 23 skipping to change at page 37, line 19
-- The snmpTlstmSession Group -- The snmpTlstmSession Group
snmpTlstmSession OBJECT IDENTIFIER ::= { snmpTlstmObjects 1 } snmpTlstmSession OBJECT IDENTIFIER ::= { snmpTlstmObjects 1 }
snmpTlstmSessionOpens OBJECT-TYPE snmpTlstmSessionOpens OBJECT-TYPE
SYNTAX Counter32 SYNTAX Counter32
MAX-ACCESS read-only MAX-ACCESS read-only
STATUS current STATUS current
DESCRIPTION DESCRIPTION
"The number of times an openSession() request has been executed "The number of times an openSession() request has been executed
as an (D)TLS client, regardless of whether it succeeded or as a (D)TLS client, regardless of whether it succeeded or
failed." failed."
::= { snmpTlstmSession 1 } ::= { snmpTlstmSession 1 }
snmpTlstmSessionClientCloses OBJECT-TYPE snmpTlstmSessionClientCloses OBJECT-TYPE
SYNTAX Counter32 SYNTAX Counter32
MAX-ACCESS read-only MAX-ACCESS read-only
STATUS current STATUS current
DESCRIPTION DESCRIPTION
"The number of times a closeSession() request has been "The number of times a closeSession() request has been
executed as an (D)TLS client, regardless of whether it executed as an (D)TLS client, regardless of whether it
skipping to change at page 39, line 47 skipping to change at page 38, line 44
suitable mapping row in the snmpTlstmCertToTSNTable." suitable mapping row in the snmpTlstmCertToTSNTable."
::= { snmpTlstmSession 7 } ::= { snmpTlstmSession 7 }
snmpTlstmSessionUnknownServerCertificate OBJECT-TYPE snmpTlstmSessionUnknownServerCertificate OBJECT-TYPE
SYNTAX Counter32 SYNTAX Counter32
MAX-ACCESS read-only MAX-ACCESS read-only
STATUS current STATUS current
DESCRIPTION DESCRIPTION
"The number of times an outgoing session was not established "The number of times an outgoing session was not established
on an (D)TLS client because the server certificate presented on an (D)TLS client because the server certificate presented
by a SNMP over (D)TLS server was invalid because no by an SNMP over (D)TLS server was invalid because no
configured fingerprint or CA was acceptable to validate it. configured fingerprint or Certification Authority (CA) was
acceptable to validate it.
This may result because there was no entry in the This may result because there was no entry in the
snmpTlstmAddrTable or because no path could be found to a snmpTlstmAddrTable or because no path could be found to a
known certification authority." known CA."
::= { snmpTlstmSession 8 } ::= { snmpTlstmSession 8 }
snmpTlstmSessionInvalidServerCertificates OBJECT-TYPE snmpTlstmSessionInvalidServerCertificates OBJECT-TYPE
SYNTAX Counter32 SYNTAX Counter32
MAX-ACCESS read-only MAX-ACCESS read-only
STATUS current STATUS current
DESCRIPTION DESCRIPTION
"The number of times an outgoing session was not established "The number of times an outgoing session was not established
on an (D)TLS client because the server certificate presented on an (D)TLS client because the server certificate presented
by an SNMP over (D)TLS server could not be validated even if by an SNMP over (D)TLS server could not be validated even if
the fingerprint or expected validation path was known. I.E., the fingerprint or expected validation path was known. That
a cryptographic validation error occurred during certificate is, a cryptographic validation error occurred during
validation processing. certificate validation processing.
Reasons for invalidation include, but are not Reasons for invalidation include, but are not
limited to, cryptographic validation failures." limited to, cryptographic validation failures."
::= { snmpTlstmSession 9 } ::= { snmpTlstmSession 9 }
snmpTlstmSessionInvalidCaches OBJECT-TYPE snmpTlstmSessionInvalidCaches OBJECT-TYPE
SYNTAX Counter32 SYNTAX Counter32
MAX-ACCESS read-only MAX-ACCESS read-only
STATUS current STATUS current
DESCRIPTION DESCRIPTION
skipping to change at page 40, line 46 skipping to change at page 39, line 44
-- Certificate mapping -- Certificate mapping
snmpTlstmCertificateMapping OBJECT IDENTIFIER ::= { snmpTlstmConfig 1 } snmpTlstmCertificateMapping OBJECT IDENTIFIER ::= { snmpTlstmConfig 1 }
snmpTlstmCertToTSNCount OBJECT-TYPE snmpTlstmCertToTSNCount OBJECT-TYPE
SYNTAX Gauge32 SYNTAX Gauge32
MAX-ACCESS read-only MAX-ACCESS read-only
STATUS current STATUS current
DESCRIPTION DESCRIPTION
"A count of the number of entries in the "A count of the number of entries in the
snmpTlstmCertToTSNTable" snmpTlstmCertToTSNTable."
::= { snmpTlstmCertificateMapping 1 } ::= { snmpTlstmCertificateMapping 1 }
snmpTlstmCertToTSNTableLastChanged OBJECT-TYPE snmpTlstmCertToTSNTableLastChanged OBJECT-TYPE
SYNTAX TimeStamp SYNTAX TimeStamp
MAX-ACCESS read-only MAX-ACCESS read-only
STATUS current STATUS current
DESCRIPTION DESCRIPTION
"The value of sysUpTime.0 when the snmpTlstmCertToTSNTable was "The value of sysUpTime.0 when the snmpTlstmCertToTSNTable was
last modified through any means, or 0 if it has not been last modified through any means, or 0 if it has not been
modified since the command responder was started." modified since the command responder was started."
::= { snmpTlstmCertificateMapping 2 } ::= { snmpTlstmCertificateMapping 2 }
snmpTlstmCertToTSNTable OBJECT-TYPE snmpTlstmCertToTSNTable OBJECT-TYPE
SYNTAX SEQUENCE OF SnmpTlstmCertToTSNEntry SYNTAX SEQUENCE OF SnmpTlstmCertToTSNEntry
MAX-ACCESS not-accessible MAX-ACCESS not-accessible
STATUS current STATUS current
DESCRIPTION DESCRIPTION
"This table is used by a (D)TLS server to map the (D)TLS "This table is used by a (D)TLS server to map the (D)TLS
client's presented X.509 certificate to a tmSecurityName. client's presented X.509 certificate to a tmSecurityName.
On an incoming (D)TLS/SNMP connection the client's presented On an incoming (D)TLS/SNMP connection, the client's presented
certificate must either be validated based on an established certificate must either be validated based on an established
trust anchor, or it must directly match a fingerprint in this trust anchor, or it must directly match a fingerprint in this
table. This table does not provide any mechanisms for table. This table does not provide any mechanisms for
configuring the trust anchors; the transfer of any needed configuring the trust anchors; the transfer of any needed
trusted certificates for path validation is expected to occur trusted certificates for path validation is expected to occur
through an out-of-band transfer. through an out-of-band transfer.
Once the certificate has been found acceptable (either by path Once the certificate has been found acceptable (either by path
validation or directly matching a fingerprint in this table), validation or directly matching a fingerprint in this table),
this table is consulted to determine the appropriate this table is consulted to determine the appropriate
tmSecurityName to identify with the remote connection. This tmSecurityName to identify with the remote connection. This
is done by considering each active row from this table in is done by considering each active row from this table in
prioritized order according to its snmpTlstmCertToTSNID value. prioritized order according to its snmpTlstmCertToTSNID value.
Each row's snmpTlstmCertToTSNFingerprint value determines Each row's snmpTlstmCertToTSNFingerprint value determines
whether the row is a match for the incoming connection: whether the row is a match for the incoming connection:
1) If the row's snmpTlstmCertToTSNFingerprint value 1) If the row's snmpTlstmCertToTSNFingerprint value
identifies the presented certificate then consider the identifies the presented certificate, then consider the
row as a successful match. row as a successful match.
2) If the row's snmpTlstmCertToTSNFingerprint value 2) If the row's snmpTlstmCertToTSNFingerprint value
identifies a locally held copy of a trusted CA identifies a locally held copy of a trusted CA
certificate and that CA certificate was used to certificate and that CA certificate was used to
validate the path to the presented certificate then validate the path to the presented certificate, then
consider the row as a successful match. consider the row as a successful match.
Once a matching row has been found, the Once a matching row has been found, the
snmpTlstmCertToTSNMapType value can be used to determine how snmpTlstmCertToTSNMapType value can be used to determine how
the tmSecurityName to associate with the session should be the tmSecurityName to associate with the session should be
determined. See the snmpTlstmCertToTSNMapType column's determined. See the snmpTlstmCertToTSNMapType column's
DESCRIPTION for details on determining the tmSecurityName DESCRIPTION for details on determining the tmSecurityName
value. If it is impossible to determine a tmSecurityName from value. If it is impossible to determine a tmSecurityName from
the row's data combined with the data presented in the the row's data combined with the data presented in the
certificate then additional rows MUST be searched looking for certificate, then additional rows MUST be searched looking for
another potential match. If a resulting tmSecurityName mapped another potential match. If a resulting tmSecurityName mapped
from a given row is not compatible with the needed from a given row is not compatible with the needed
requirements of a tmSecurityName (e.g., VACM imposes a requirements of a tmSecurityName (e.g., VACM imposes a
32-octet-maximum length and the certificate derived 32-octet-maximum length and the certificate derived
securityName could be longer) then it must be considered an securityName could be longer), then it must be considered an
invalid match and additional rows MUST be searched looking for invalid match and additional rows MUST be searched looking for
another potential match. another potential match.
If no matching and valid row can be found, the connection MUST If no matching and valid row can be found, the connection MUST
be closed and SNMP messages MUST NOT be accepted over it. be closed and SNMP messages MUST NOT be accepted over it.
Missing values of snmpTlstmCertToTSNID are acceptable and Missing values of snmpTlstmCertToTSNID are acceptable and
implementations should continue to the next highest numbered implementations should continue to the next highest numbered
row. It is recommended that administrators skip index values row. It is recommended that administrators skip index values
to leave room for the insertion of future rows (E.G., use values to leave room for the insertion of future rows (for example,
of 10 and 20 when creating initial rows). use values of 10 and 20 when creating initial rows).
Users are encouraged to make use of certificates with Users are encouraged to make use of certificates with
subjectAltName fields that can be used as tmSecurityNames so subjectAltName fields that can be used as tmSecurityNames so
that a single root CA certificate can allow all child that a single root CA certificate can allow all child
certificate's subjectAltName to map directly to a certificate's subjectAltName to map directly to a
tmSecurityName via a 1:1 transformation. However, this table tmSecurityName via a 1:1 transformation. However, this table
is flexible to allow for situations where existing deployed is flexible to allow for situations where existing deployed
certificate infrastructures do not provide adequate certificate infrastructures do not provide adequate
subjectAltName values for use as tmSecurityNames. subjectAltName values for use as tmSecurityNames.
Certificates may also be mapped to tmSecurityNames using the Certificates may also be mapped to tmSecurityNames using the
skipping to change at page 43, line 47 skipping to change at page 43, line 4
"Specifies the mapping type for deriving a tmSecurityName from "Specifies the mapping type for deriving a tmSecurityName from
a certificate. Details for mapping of a particular type SHALL a certificate. Details for mapping of a particular type SHALL
be specified in the DESCRIPTION clause of the OBJECT-IDENTITY be specified in the DESCRIPTION clause of the OBJECT-IDENTITY
that describes the mapping. If a mapping succeeds it will that describes the mapping. If a mapping succeeds it will
return a tmSecurityName for use by the TLSTM model and return a tmSecurityName for use by the TLSTM model and
processing stops. processing stops.
If the resulting mapped value is not compatible with the If the resulting mapped value is not compatible with the
needed requirements of a tmSecurityName (e.g., VACM imposes a needed requirements of a tmSecurityName (e.g., VACM imposes a
32-octet-maximum length and the certificate derived 32-octet-maximum length and the certificate derived
securityName could be longer) then future rows MUST be securityName could be longer), then future rows MUST be
searched for additional snmpTlstmCertToTSNFingerprint matches searched for additional snmpTlstmCertToTSNFingerprint matches
to look for a mapping that succeeds. to look for a mapping that succeeds.
Suitable values for assigning to this object that are defined Suitable values for assigning to this object that are defined
within the SNMP-TLS-TM-MIB can be found in the within the SNMP-TLS-TM-MIB can be found in the
snmpTlstmCertToTSNMIdentities portion of the MIB tree." snmpTlstmCertToTSNMIdentities portion of the MIB tree."
DEFVAL { snmpTlstmCertSpecified } DEFVAL { snmpTlstmCertSpecified }
::= { snmpTlstmCertToTSNEntry 3 } ::= { snmpTlstmCertToTSNEntry 3 }
snmpTlstmCertToTSNData OBJECT-TYPE snmpTlstmCertToTSNData OBJECT-TYPE
skipping to change at page 45, line 23 skipping to change at page 44, line 31
an inconsistentValue error." an inconsistentValue error."
::= { snmpTlstmCertToTSNEntry 6 } ::= { snmpTlstmCertToTSNEntry 6 }
-- Maps tmSecurityNames to certificates for use by the SNMP-TARGET-MIB -- Maps tmSecurityNames to certificates for use by the SNMP-TARGET-MIB
snmpTlstmParamsCount OBJECT-TYPE snmpTlstmParamsCount OBJECT-TYPE
SYNTAX Gauge32 SYNTAX Gauge32
MAX-ACCESS read-only MAX-ACCESS read-only
STATUS current STATUS current
DESCRIPTION DESCRIPTION
"A count of the number of entries in the snmpTlstmParamsTable" "A count of the number of entries in the snmpTlstmParamsTable."
::= { snmpTlstmCertificateMapping 4 } ::= { snmpTlstmCertificateMapping 4 }
snmpTlstmParamsTableLastChanged OBJECT-TYPE snmpTlstmParamsTableLastChanged OBJECT-TYPE
SYNTAX TimeStamp SYNTAX TimeStamp
MAX-ACCESS read-only MAX-ACCESS read-only
STATUS current STATUS current
DESCRIPTION DESCRIPTION
"The value of sysUpTime.0 when the snmpTlstmParamsTable "The value of sysUpTime.0 when the snmpTlstmParamsTable
was last modified through any means, or 0 if it has not been was last modified through any means, or 0 if it has not been
modified since the command responder was started." modified since the command responder was started."
skipping to change at page 47, line 31 skipping to change at page 46, line 48
An attempt to set these objects while the value of An attempt to set these objects while the value of
snmpTlstmParamsRowStatus is active(1) will result in snmpTlstmParamsRowStatus is active(1) will result in
an inconsistentValue error." an inconsistentValue error."
::= { snmpTlstmParamsEntry 3 } ::= { snmpTlstmParamsEntry 3 }
snmpTlstmAddrCount OBJECT-TYPE snmpTlstmAddrCount OBJECT-TYPE
SYNTAX Gauge32 SYNTAX Gauge32
MAX-ACCESS read-only MAX-ACCESS read-only
STATUS current STATUS current
DESCRIPTION DESCRIPTION
"A count of the number of entries in the snmpTlstmAddrTable" "A count of the number of entries in the snmpTlstmAddrTable."
::= { snmpTlstmCertificateMapping 7 } ::= { snmpTlstmCertificateMapping 7 }
snmpTlstmAddrTableLastChanged OBJECT-TYPE snmpTlstmAddrTableLastChanged OBJECT-TYPE
SYNTAX TimeStamp SYNTAX TimeStamp
MAX-ACCESS read-only MAX-ACCESS read-only
STATUS current STATUS current
DESCRIPTION DESCRIPTION
"The value of sysUpTime.0 when the snmpTlstmAddrTable "The value of sysUpTime.0 when the snmpTlstmAddrTable
was last modified through any means, or 0 if it has not been was last modified through any means, or 0 if it has not been
modified since the command responder was started." modified since the command responder was started."
::= { snmpTlstmCertificateMapping 8 } ::= { snmpTlstmCertificateMapping 8 }
snmpTlstmAddrTable OBJECT-TYPE snmpTlstmAddrTable OBJECT-TYPE
SYNTAX SEQUENCE OF SnmpTlstmAddrEntry SYNTAX SEQUENCE OF SnmpTlstmAddrEntry
MAX-ACCESS not-accessible MAX-ACCESS not-accessible
STATUS current STATUS current
DESCRIPTION DESCRIPTION
"This table is used by a (D)TLS client when a (D)TLS "This table is used by a (D)TLS client when a (D)TLS
connection is being set up using an entry in the connection is being set up using an entry in the
SNMP-TARGET-MIB. It extends the SNMP-TARGET-MIB's SNMP-TARGET-MIB. It extends the SNMP-TARGET-MIB's
snmpTargetAddrTable so that the client can verify that the snmpTargetAddrTable so that the client can verify that the
correct server has been reached. This verification can use correct server has been reached. This verification can use
either a certificate fingerprint, or an identity either a certificate fingerprint, or an identity
authenticated via certification path validation. authenticated via certification path validation.
If there is an active row in this table corresponding to the If there is an active row in this table corresponding to the
entry in the SNMP-TARGET-MIB that was used to establish the entry in the SNMP-TARGET-MIB that was used to establish the
connection, and the row's snmpTlstmAddrServerFingerprint connection, and the row's snmpTlstmAddrServerFingerprint
column has non-empty value, then the server's presented column has non-empty value, then the server's presented
certificate is compared with the certificate is compared with the
snmpTlstmAddrServerFingerprint value (and the snmpTlstmAddrServerFingerprint value (and the
snmpTlstmAddrServerIdentity column is ignored). If the snmpTlstmAddrServerIdentity column is ignored). If the
fingerprint matches, the verification has succeeded. If the fingerprint matches, the verification has succeeded. If the
fingerprint does not match then the connection MUST be fingerprint does not match, then the connection MUST be
closed. closed.
If the server's presented certificate has passed If the server's presented certificate has passed
certification path validation [RFC5280] to a configured certification path validation [RFC5280] to a configured
trust anchor, and an active row exists with a zero-length trust anchor, and an active row exists with a zero-length
snmpTlstmAddrServerFingerprint value, then the snmpTlstmAddrServerFingerprint value, then the
snmpTlstmAddrServerIdentity column contains the expected snmpTlstmAddrServerIdentity column contains the expected
host name. This expected host name is then compared against host name. This expected host name is then compared against
the server's certificate as follows: the server's certificate as follows:
- Implementations MUST support matching the expected host - Implementations MUST support matching the expected host
name against a dNSName in the subjectAltName extension name against a dNSName in the subjectAltName extension
field and MAY support checking the name against the field and MAY support checking the name against the
CommonName portion of the subject distinguished name. CommonName portion of the subject distinguished name.
- The '*' (ASCII 0x2a) wildcard character is allowed in the - The '*' (ASCII 0x2a) wildcard character is allowed in the
dNSName of the subjectAltName extension (and in common dNSName of the subjectAltName extension (and in common
name, if used to store the host name), but only as the name, if used to store the host name), but only as the
left-most (least significant) DNS label in that value. left-most (least significant) DNS label in that value.
This wildcard matches any left-most DNS label in the This wildcard matches any left-most DNS label in the
server name. That is, the subject *.example.com matches server name. That is, the subject *.example.com matches
the server names a.example.com and b.example.com, but does the server names a.example.com and b.example.com, but does
not match example.com or a.b.example.com. Implementations not match example.com or a.b.example.com. Implementations
MUST support wildcards in certificates as specified above, MUST support wildcards in certificates as specified above,
but MAY provide a configuration option to disable them. but MAY provide a configuration option to disable them.
- If the locally configured name is an internationalized - If the locally configured name is an internationalized
domain name, conforming implementations MUST convert it to domain name, conforming implementations MUST convert it to
the ASCII Compatible Encoding (ACE) format for performing the ASCII Compatible Encoding (ACE) format for performing
comparisons, as specified in Section 7 of [RFC5280]. comparisons, as specified in Section 7 of [RFC5280].
If the expected host name fails these conditions then the If the expected host name fails these conditions then the
connection MUST be closed. connection MUST be closed.
If there is no row in this table corresponding to the entry If there is no row in this table corresponding to the entry
in the SNMP-TARGET-MIB and the server can be authorized by in the SNMP-TARGET-MIB and the server can be authorized by
another, implementation dependent means, then the connection another, implementation-dependent means, then the connection
MAY still proceed." MAY still proceed."
::= { snmpTlstmCertificateMapping 9 } ::= { snmpTlstmCertificateMapping 9 }
snmpTlstmAddrEntry OBJECT-TYPE snmpTlstmAddrEntry OBJECT-TYPE
SYNTAX SnmpTlstmAddrEntry SYNTAX SnmpTlstmAddrEntry
MAX-ACCESS not-accessible MAX-ACCESS not-accessible
STATUS current STATUS current
DESCRIPTION DESCRIPTION
"A conceptual row containing a copy of a certificate's "A conceptual row containing a copy of a certificate's
fingerprint for a given snmpTargetAddrEntry. The values in fingerprint for a given snmpTargetAddrEntry. The values in
this row should be ignored if the connection that needs to be this row should be ignored if the connection that needs to be
established, as indicated by the SNMP-TARGET-MIB established, as indicated by the SNMP-TARGET-MIB
infrastructure, is not a (D)TLS based connection. If an infrastructure, is not a (D)TLS based connection. If an
snmpTlstmAddrEntry exists for a given snmpTargetAddrEntry then snmpTlstmAddrEntry exists for a given snmpTargetAddrEntry, then
the presented server certificate MUST match or the connection the presented server certificate MUST match or the connection
MUST NOT be established. If a row in this table does not MUST NOT be established. If a row in this table does not
exist to match a snmpTargetAddrEntry row then the connection exist to match an snmpTargetAddrEntry row, then the connection
SHOULD still proceed if some other certificate validation path SHOULD still proceed if some other certificate validation path
algorithm (e.g. RFC5280) can be used." algorithm (e.g., RFC 5280) can be used."
INDEX { IMPLIED snmpTargetAddrName } INDEX { IMPLIED snmpTargetAddrName }
::= { snmpTlstmAddrTable 1 } ::= { snmpTlstmAddrTable 1 }
SnmpTlstmAddrEntry ::= SEQUENCE { SnmpTlstmAddrEntry ::= SEQUENCE {
snmpTlstmAddrServerFingerprint SnmpTLSFingerprint, snmpTlstmAddrServerFingerprint SnmpTLSFingerprint,
snmpTlstmAddrServerIdentity SnmpAdminString, snmpTlstmAddrServerIdentity SnmpAdminString,
snmpTlstmAddrStorageType StorageType, snmpTlstmAddrStorageType StorageType,
snmpTlstmAddrRowStatus RowStatus snmpTlstmAddrRowStatus RowStatus
} }
skipping to change at page 51, line 18 skipping to change at page 50, line 41
::= { snmpTlstmAddrEntry 4 } ::= { snmpTlstmAddrEntry 4 }
-- ************************************************ -- ************************************************
-- snmpTlstmNotifications - Notifications Information -- snmpTlstmNotifications - Notifications Information
-- ************************************************ -- ************************************************
snmpTlstmServerCertificateUnknown NOTIFICATION-TYPE snmpTlstmServerCertificateUnknown NOTIFICATION-TYPE
OBJECTS { snmpTlstmSessionUnknownServerCertificate } OBJECTS { snmpTlstmSessionUnknownServerCertificate }
STATUS current STATUS current
DESCRIPTION DESCRIPTION
"Notification that the server certificate presented by a SNMP "Notification that the server certificate presented by an SNMP
over (D)TLS server was invalid because no configured over (D)TLS server was invalid because no configured
fingerprint or CA was acceptable to validate it. This may be fingerprint or CA was acceptable to validate it. This may be
because there was no entry in the snmpTlstmAddrTable or because there was no entry in the snmpTlstmAddrTable or
because no path could be found to known certificate because no path could be found to known Certification
authority. Authority.
To avoid notification loops, this notification MUST NOT be To avoid notification loops, this notification MUST NOT be
sent to servers that themselves have triggered the sent to servers that themselves have triggered the
notification." notification."
::= { snmpTlstmNotifications 1 } ::= { snmpTlstmNotifications 1 }
snmpTlstmServerInvalidCertificate NOTIFICATION-TYPE snmpTlstmServerInvalidCertificate NOTIFICATION-TYPE
OBJECTS { snmpTlstmAddrServerFingerprint, OBJECTS { snmpTlstmAddrServerFingerprint,
snmpTlstmSessionInvalidServerCertificates} snmpTlstmSessionInvalidServerCertificates}
STATUS current STATUS current
DESCRIPTION DESCRIPTION
"Notification that the server certificate presented by an SNMP "Notification that the server certificate presented by an SNMP
over (D)TLS server could not be validated even if the over (D)TLS server could not be validated even if the
fingerprint or expected validation path was known. I.E., a fingerprint or expected validation path was known. That is, a
cryptographic validation error occurred during certificate cryptographic validation error occurred during certificate
validation processing. validation processing.
To avoid notification loops, this notification MUST NOT be To avoid notification loops, this notification MUST NOT be
sent to servers that themselves have triggered the sent to servers that themselves have triggered the
notification." notification."
::= { snmpTlstmNotifications 2 } ::= { snmpTlstmNotifications 2 }
-- ************************************************ -- ************************************************
-- snmpTlstmCompliances - Conformance Information -- snmpTlstmCompliances - Conformance Information
skipping to change at page 52, line 41 skipping to change at page 52, line 24
snmpTlstmSessionServerCloses, snmpTlstmSessionServerCloses,
snmpTlstmSessionNoSessions, snmpTlstmSessionNoSessions,
snmpTlstmSessionInvalidClientCertificates, snmpTlstmSessionInvalidClientCertificates,
snmpTlstmSessionUnknownServerCertificate, snmpTlstmSessionUnknownServerCertificate,
snmpTlstmSessionInvalidServerCertificates, snmpTlstmSessionInvalidServerCertificates,
snmpTlstmSessionInvalidCaches snmpTlstmSessionInvalidCaches
} }
STATUS current STATUS current
DESCRIPTION DESCRIPTION
"A collection of objects for maintaining "A collection of objects for maintaining
statistical information of an SNMP engine which statistical information of an SNMP engine that
implements the SNMP TLS Transport Model." implements the SNMP TLS Transport Model."
::= { snmpTlstmGroups 1 } ::= { snmpTlstmGroups 1 }
snmpTlstmIncomingGroup OBJECT-GROUP snmpTlstmIncomingGroup OBJECT-GROUP
OBJECTS { OBJECTS {
snmpTlstmCertToTSNCount, snmpTlstmCertToTSNCount,
snmpTlstmCertToTSNTableLastChanged, snmpTlstmCertToTSNTableLastChanged,
snmpTlstmCertToTSNFingerprint, snmpTlstmCertToTSNFingerprint,
snmpTlstmCertToTSNMapType, snmpTlstmCertToTSNMapType,
snmpTlstmCertToTSNData, snmpTlstmCertToTSNData,
snmpTlstmCertToTSNStorageType, snmpTlstmCertToTSNStorageType,
snmpTlstmCertToTSNRowStatus snmpTlstmCertToTSNRowStatus
} }
STATUS current STATUS current
DESCRIPTION DESCRIPTION
"A collection of objects for maintaining "A collection of objects for maintaining
incoming connection certificate mappings to incoming connection certificate mappings to
tmSecurityNames of an SNMP engine which implements the tmSecurityNames of an SNMP engine that implements the
SNMP TLS Transport Model." SNMP TLS Transport Model."
::= { snmpTlstmGroups 2 } ::= { snmpTlstmGroups 2 }
snmpTlstmOutgoingGroup OBJECT-GROUP snmpTlstmOutgoingGroup OBJECT-GROUP
OBJECTS { OBJECTS {
snmpTlstmParamsCount, snmpTlstmParamsCount,
snmpTlstmParamsTableLastChanged, snmpTlstmParamsTableLastChanged,
snmpTlstmParamsClientFingerprint, snmpTlstmParamsClientFingerprint,
snmpTlstmParamsStorageType, snmpTlstmParamsStorageType,
snmpTlstmParamsRowStatus, snmpTlstmParamsRowStatus,
skipping to change at page 54, line 21 skipping to change at page 53, line 47
A session is discussed throughout this document as meaning a security A session is discussed throughout this document as meaning a security
association between two TLSTM instances. State information for the association between two TLSTM instances. State information for the
sessions are maintained in each TLSTM implementation and this sessions are maintained in each TLSTM implementation and this
information is created and destroyed as sessions are opened and information is created and destroyed as sessions are opened and
closed. A "broken" session (one side up and one side down) can closed. A "broken" session (one side up and one side down) can
result if one side of a session is brought down abruptly (i.e., result if one side of a session is brought down abruptly (i.e.,
reboot, power outage, etc.). Whenever possible, implementations reboot, power outage, etc.). Whenever possible, implementations
SHOULD provide graceful session termination through the use of TLS SHOULD provide graceful session termination through the use of TLS
disconnect messages. Implementations SHOULD also have a system in disconnect messages. Implementations SHOULD also have a system in
place for detecting "broken" sessions through the use of heartbeats place for detecting "broken" sessions through the use of heartbeats
[I-D.seggelmann-tls-dtls-heartbeat] or other detection mechanisms. [HEARTBEAT] or other detection mechanisms.
Implementations SHOULD limit the lifetime of established sessions Implementations SHOULD limit the lifetime of established sessions
depending on the algorithms used for generation of the master session depending on the algorithms used for generation of the master session
secret, the privacy and integrity algorithms used to protect secret, the privacy and integrity algorithms used to protect
messages, the environment of the session, the amount of data messages, the environment of the session, the amount of data
transferred, and the sensitivity of the data. transferred, and the sensitivity of the data.
8.2. Notification Receiver Credential Selection 8.2. Notification Receiver Credential Selection
When an SNMP engine needs to establish an outgoing session for When an SNMP engine needs to establish an outgoing session for
notifications, the snmpTargetParamsTable includes an entry for the notifications, the snmpTargetParamsTable includes an entry for the
snmpTargetParamsSecurityName of the target. Servers that wish to snmpTargetParamsSecurityName of the target. Servers that wish to
support multiple principals at a particular port SHOULD make use of support multiple principals at a particular port SHOULD make use of
the Server Name Indication extension defined in Section 3.1 of the Server Name Indication extension defined in Section 3.1 of
[RFC4366]. Without the Server Name Indication the receiving SNMP [RFC4366]. Without the Server Name Indication the receiving SNMP
engine (Server) will not know which (D)TLS certificate to offer to engine (server) will not know which (D)TLS certificate to offer to
the Client so that the tmSecurityName identity-authentication will be the client so that the tmSecurityName identity-authentication will be
successful. successful.
Another solution is to maintain a one-to-one mapping between Another solution is to maintain a one-to-one mapping between
certificates and incoming ports for notification receivers. This can certificates and incoming ports for notification receivers. This can
be handled at the notification originator by configuring the be handled at the notification originator by configuring the
snmpTargetAddrTable (snmpTargetAddrTDomain and snmpTargetAddrTable (snmpTargetAddrTDomain and
snmpTargetAddrTAddress) and requiring the receiving SNMP engine to snmpTargetAddrTAddress) and requiring the receiving SNMP engine to
monitor multiple incoming static ports based on which principals are monitor multiple incoming static ports based on which principals are
capable of receiving notifications. capable of receiving notifications.
skipping to change at page 55, line 20 skipping to change at page 55, line 8
retrieve or manipulate objects maintained on the remote SNMP entity. retrieve or manipulate objects maintained on the remote SNMP entity.
[RFC5343] introduces a well-known localEngineID and a discovery [RFC5343] introduces a well-known localEngineID and a discovery
mechanism that can be used to learn the snmpEngineID of a remote SNMP mechanism that can be used to learn the snmpEngineID of a remote SNMP
protocol engine. Implementations are RECOMMENDED to support and use protocol engine. Implementations are RECOMMENDED to support and use
the contextEngineID discovery mechanism defined in [RFC5343]. the contextEngineID discovery mechanism defined in [RFC5343].
8.4. Transport Considerations 8.4. Transport Considerations
This document defines how SNMP messages can be transmitted over the This document defines how SNMP messages can be transmitted over the
TLS and DTLS based protocols. Each of these protocols are TLS- and DTLS-based protocols. Each of these protocols are
additionally based on other transports (TCP and UDP). These two base additionally based on other transports (TCP and UDP). These two base
protocols also have operational considerations that must be taken protocols also have operational considerations that must be taken
into consideration when selecting a (D)TLS based protocol to use such into consideration when selecting a (D)TLS-based protocol to use such
as its performance in degraded or limited networks. It is beyond the as its performance in degraded or limited networks. It is beyond the
scope of this document to summarize the characteristics of these scope of this document to summarize the characteristics of these
transport mechanisms. Please refer to the base protocol documents transport mechanisms. Please refer to the base protocol documents
for details on messaging considerations with respect to MTU size, for details on messaging considerations with respect to MTU size,
fragmentation, performance in lossy-networks, etc. fragmentation, performance in lossy networks, etc.
9. Security Considerations 9. Security Considerations
This document describes a transport model that permits SNMP to This document describes a transport model that permits SNMP to
utilize (D)TLS security services. The security threats and how the utilize (D)TLS security services. The security threats and how the
(D)TLS transport model mitigates these threats are covered in detail (D)TLS transport model mitigates these threats are covered in detail
throughout this document. Security considerations for DTLS are throughout this document. Security considerations for DTLS are
covered in [RFC4347] and security considerations for TLS are covered in [RFC4347] and security considerations for TLS are
described in Section 11 and Appendices D, E, and F of TLS 1.2 described in Section 11 and Appendices D, E, and F of TLS 1.2
[RFC5246]. When run over a connectionless transport such as UDP, [RFC5246]. When run over a connectionless transport such as UDP,
DTLS is more vulnerable to denial of service attacks from spoofed IP DTLS is more vulnerable to denial-of-service attacks from spoofed IP
addresses; see Section 4.2 for details how the cookie exchange is addresses; see Section 4.2 for details how the cookie exchange is
used to address this issue. used to address this issue.
9.1. Certificates, Authentication, and Authorization 9.1. Certificates, Authentication, and Authorization
Implementations are responsible for providing a security certificate Implementations are responsible for providing a security certificate
installation and configuration mechanism. Implementations SHOULD installation and configuration mechanism. Implementations SHOULD
support certificate revocation lists. support certificate revocation lists.
(D)TLS provides for authentication of the identity of both the (D)TLS (D)TLS provides for authentication of the identity of both the (D)TLS
server and the (D)TLS client. Access to MIB objects for the server and the (D)TLS client. Access to MIB objects for the
authenticated principal MUST be enforced by an access control authenticated principal MUST be enforced by an access control
subsystem (e.g. the VACM). subsystem (e.g., the VACM).
Authentication of the command generator principal's identity is Authentication of the command generator principal's identity is
important for use with the SNMP access control subsystem to ensure important for use with the SNMP access control subsystem to ensure
that only authorized principals have access to potentially sensitive that only authorized principals have access to potentially sensitive
data. The authenticated identity of the command generator data. The authenticated identity of the command generator
principal's certificate is mapped to an SNMP model-independent principal's certificate is mapped to an SNMP model-independent
securityName for use with SNMP access control. securityName for use with SNMP access control.
The (D)TLS handshake only provides assurance that the certificate of The (D)TLS handshake only provides assurance that the certificate of
the authenticated identity has been signed by an configured accepted the authenticated identity has been signed by a configured accepted
certification authority. (D)TLS has no way to further authorize or Certification Authority. (D)TLS has no way to further authorize or
reject access based on the authenticated identity. An Access Control reject access based on the authenticated identity. An Access Control
Model (such as the VACM) provides access control and authorization of Model (such as the VACM) provides access control and authorization of
a command generator's requests to a command responder and a a command generator's requests to a command responder and a
notification receiver's authorization to receive Notifications from a notification receiver's authorization to receive Notifications from a
notification originator. However to avoid man-in-the-middle attacks notification originator. However, to avoid man-in-the-middle
both ends of the (D)TLS based connection MUST check the certificate attacks, both ends of the (D)TLS-based connection MUST check the
presented by the other side against what was expected. For example, certificate presented by the other side against what was expected.
command generators must check that the command responder presented For example, command generators must check that the command responder
and authenticated itself with a X.509 certificate that was expected. presented and authenticated itself with a X.509 certificate that was
Not doing so would allow an impostor, at a minimum, to present false expected. Not doing so would allow an impostor, at a minimum, to
data, receive sensitive information and/or provide a false belief present false data, receive sensitive information and/or provide a
that configuration was actually received and acted upon. false belief that configuration was actually received and acted upon.
Authenticating and verifying the identity of the (D)TLS server and Authenticating and verifying the identity of the (D)TLS server and
the (D)TLS client for all operations ensures the authenticity of the the (D)TLS client for all operations ensures the authenticity of the
SNMP engine that provides MIB data. SNMP engine that provides MIB data.
The instructions found in the DESCRIPTION clause of the The instructions found in the DESCRIPTION clause of the
snmpTlstmCertToTSNTable object must be followed exactly. It is also snmpTlstmCertToTSNTable object must be followed exactly. It is also
important that the rows of the table be searched in prioritized order important that the rows of the table be searched in prioritized order
starting with the row containing the lowest numbered starting with the row containing the lowest numbered
snmpTlstmCertToTSNID value. snmpTlstmCertToTSNID value.
skipping to change at page 57, line 8 skipping to change at page 56, line 41
Implementations of TLS typically support multiple versions of the Implementations of TLS typically support multiple versions of the
Transport Layer Security protocol as well as the older Secure Sockets Transport Layer Security protocol as well as the older Secure Sockets
Layer (SSL) protocol. Because of known security vulnerabilities, Layer (SSL) protocol. Because of known security vulnerabilities,
TLSTM clients and servers MUST NOT request, offer, or use SSL 2.0. TLSTM clients and servers MUST NOT request, offer, or use SSL 2.0.
See Appendix E.2 of [RFC5246] for further details. See Appendix E.2 of [RFC5246] for further details.
9.2.2. Perfect Forward Secrecy 9.2.2. Perfect Forward Secrecy
The use of Perfect Forward Secrecy is RECOMMENDED and can be provided The use of Perfect Forward Secrecy is RECOMMENDED and can be provided
by (D)TLS with appropriately selected cipher suites, as discussed in by (D)TLS with appropriately selected cipher_suites, as discussed in
Appendix F of [RFC5246]. Appendix F of [RFC5246].
9.3. Use with SNMPv1/SNMPv2c Messages 9.3. Use with SNMPv1/SNMPv2c Messages
The SNMPv1 and SNMPv2c message processing described in [RFC3584] (BCP The SNMPv1 and SNMPv2c message processing described in [RFC3584] (BCP
74) always selects the SNMPv1 or SNMPv2c Security Models, 74) always selects the SNMPv1 or SNMPv2c Security Models,
respectively. Both of these and the User-based Security Model respectively. Both of these and the User-based Security Model
typically used with SNMPv3 derive the securityName and securityLevel typically used with SNMPv3 derive the securityName and securityLevel
from the SNMP message received, even when the message was received from the SNMP message received, even when the message was received
over a secure transport. Access control decisions are therefore made over a secure transport. Access control decisions are therefore made
skipping to change at page 58, line 11 skipping to change at page 57, line 45
the certificates presented by a remote (D)TLS server. the certificates presented by a remote (D)TLS server.
Modification to objects in this table need to be adequately Modification to objects in this table need to be adequately
authenticated since modification to values in this table will have authenticated since modification to values in this table will have
profound impacts to the security of outbound connections from the profound impacts to the security of outbound connections from the
device. Since knowledge of authorization rules and certificate device. Since knowledge of authorization rules and certificate
usage mechanisms may be considered sensitive, protection from usage mechanisms may be considered sensitive, protection from
disclosure of the SNMP traffic via encryption is also highly disclosure of the SNMP traffic via encryption is also highly
recommended. recommended.
o The snmpTlstmCertToTSNTable is used to specify the mapping of o The snmpTlstmCertToTSNTable is used to specify the mapping of
incoming X.509 certificates to tmSecurityNames which eventually incoming X.509 certificates to tmSecurityNames, which eventually
get mapped to a SNMPv3 securityName. Modification to objects in get mapped to a SNMPv3 securityName. Modification to objects in
this table need to be adequately authenticated since modification this table need to be adequately authenticated since modification
to values in this table will have profound impacts to the security to values in this table will have profound impacts to the security
of incoming connections to the device. Since knowledge of of incoming connections to the device. Since knowledge of
authorization rules and certificate usage mechanisms may be authorization rules and certificate usage mechanisms may be
considered sensitive, protection from disclosure of the SNMP considered sensitive, protection from disclosure of the SNMP
traffic via encryption is also highly recommended. When this traffic via encryption is also highly recommended. When this
table contains a significant number of rows it may affect the table contains a significant number of rows it may affect the
system performance when accepting new (D)TLS connections. system performance when accepting new (D)TLS connections.
skipping to change at page 58, line 34 skipping to change at page 58, line 20
vulnerable in some network environments. It is thus important to vulnerable in some network environments. It is thus important to
control even GET and/or NOTIFY access to these objects and possibly control even GET and/or NOTIFY access to these objects and possibly
to even encrypt the values of these objects when sending them over to even encrypt the values of these objects when sending them over
the network via SNMP. These are the tables and objects and their the network via SNMP. These are the tables and objects and their
sensitivity/vulnerability: sensitivity/vulnerability:
o This MIB contains a collection of counters that monitor the (D)TLS o This MIB contains a collection of counters that monitor the (D)TLS
connections being established with a device. Since knowledge of connections being established with a device. Since knowledge of
connection and certificate usage mechanisms may be considered connection and certificate usage mechanisms may be considered
sensitive, protection from disclosure of the SNMP traffic via sensitive, protection from disclosure of the SNMP traffic via
encryption is also highly recommended. encryption is highly recommended.
SNMP versions prior to SNMPv3 did not include adequate security. SNMP versions prior to SNMPv3 did not include adequate security.
Even if the network itself is secure (for example by using IPsec), 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 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 allowed to access and GET/SET (read/change/create/delete) the objects
in this MIB module. in this MIB module.
It is RECOMMENDED that implementers consider the security features as It is RECOMMENDED that implementers consider the security features as
provided by the SNMPv3 framework (see [RFC3410], section 8), provided by the SNMPv3 framework (see [RFC3410], Section 8),
including full support for the SNMPv3 cryptographic mechanisms (for including full support for the SNMPv3 cryptographic mechanisms (for
authentication and privacy). authentication and privacy).
Further, deployment of SNMP versions prior to SNMPv3 is NOT Further, deployment of SNMP versions prior to SNMPv3 is NOT
RECOMMENDED. Instead, it is RECOMMENDED to deploy SNMPv3 and to RECOMMENDED. Instead, it is RECOMMENDED to deploy SNMPv3 and to
enable cryptographic security. It is then a customer/operator enable cryptographic security. It is then a customer/operator
responsibility to ensure that the SNMP entity giving access to an responsibility to ensure that the SNMP entity giving access to an
instance of this MIB module is properly configured to give access to instance of this MIB module is properly configured to give access to
the objects only to those principals (users) that have legitimate the objects only to those principals (users) that have legitimate
rights to indeed GET or SET (change/create/delete) them. rights to indeed GET or SET (change/create/delete) them.
10. IANA Considerations 10. IANA Considerations
IANA is requested to assign: IANA has assigned:
1. Two TCP/UDP port numbers from the "Registered Ports" range of the 1. Two TCP/UDP port numbers from the "Registered Ports" range of the
Port Numbers registry, with the following keywords (where TBD1 Port Numbers registry, with the following keywords:
and TBD2 correspond to the assigned port numbers):
Keyword Decimal Description References Keyword Decimal Description References
------- ------- ----------- ---------- ------- ------- ----------- ----------
snmptls TBD1/tcp SNMP-TLS [RFC-isms-dtls-tm] snmptls 10161/tcp SNMP-TLS [RFC5953]
snmpdtls TBD1/udp SNMP-DTLS [RFC-isms-dtls-tm] snmpdtls 10161/udp SNMP-DTLS [RFC5953]
snmptls-trap TBD2/tcp SNMP-Trap-TLS [RFC-isms-dtls-tm] snmptls-trap 10162/tcp SNMP-Trap-TLS [RFC5953]
snmpdtls-trap TBD2/udp SNMP-Trap-DTLS [RFC-isms-dtls-tm] snmpdtls-trap 10162/udp SNMP-Trap-DTLS [RFC5953]
These are the default ports for receipt of SNMP command messages These are the default ports for receipt of SNMP command messages
(snmptls and snmpdtls) and SNMP notification messages (snmptls- (snmptls and snmpdtls) and SNMP notification messages (snmptls- trap
trap and snmpdtls-trap) over a TLS Transport Model as defined in and snmpdtls-trap) over a TLS Transport Model as defined in this
this document. document.
2. An SMI number under snmpDomains for the snmpTLSTCPDomain object 2. An SMI number (8) under snmpDomains for the snmpTLSTCPDomain
identifier, object identifier
3. An SMI number under snmpDomains for the snmpDTLSUDPDomain object 3. An SMI number (9) under snmpDomains for the snmpDTLSUDPDomain
identifier, object identifier
4. A SMI number under mib-2, for the MIB module in this document, 4. An SMI number (198) under mib-2, for the MIB module in this
document
5. "tls" as the corresponding prefix for the snmpTLSTCPDomain in the 5. "tls" as the corresponding prefix for the snmpTLSTCPDomain in the
SNMP Transport Model registry, SNMP Transport Domains registry
6. "dtls" as the corresponding prefix for the snmpDTLSUDPDomain in 6. "dtls" as the corresponding prefix for the snmpDTLSUDPDomain in
the SNMP Transport Model registry, the SNMP Transport Domains registry
RFC Editor's note: this section should be replaced with appropriate
descriptive assignment text after IANA assignments are made and prior
to publication.
11. Acknowledgements 11. Acknowledgements
This document closely follows and copies the Secure Shell Transport This document closely follows and copies the Secure Shell Transport
Model for SNMP documented by David Harrington and Joseph Salowey in Model for SNMP documented by David Harrington and Joseph Salowey in
[RFC5592]. [RFC5592].
This document was reviewed by the following people who helped provide This document was reviewed by the following people who helped provide
useful comments (in alphabetical order): Andy Donati, Pasi Eronen, useful comments (in alphabetical order): Andy Donati, Pasi Eronen,
David Harrington, Jeffrey Hutzelman, Alan Luchuk, Michael Peck, Tom David Harrington, Jeffrey Hutzelman, Alan Luchuk, Michael Peck, Tom
Petch, Randy Presuhn, Ray Purvis, Peter Saint-Andre, Joseph Salowey, Petch, Randy Presuhn, Ray Purvis, Peter Saint-Andre, Joseph Salowey,
Jurgen Schonwalder, Dave Shield, Robert Story. Juergen Schoenwaelder, Dave Shield, and Robert Story.
This work was supported in part by the United States Department of This work was supported in part by the United States Department of
Defense. Large portions of this document are based on work by Defense. Large portions of this document are based on work by
General Dynamics C4 Systems and the following individuals: Brian General Dynamics C4 Systems and the following individuals: Brian
Baril, Kim Bryant, Dana Deluca, Dan Hanson, Tim Huemiller, John Baril, Kim Bryant, Dana Deluca, Dan Hanson, Tim Huemiller, John
Holzhauer, Colin Hoogeboom, Dave Kornbau, Chris Knaian, Dan Knaul, Holzhauer, Colin Hoogeboom, Dave Kornbau, Chris Knaian, Dan Knaul,
Charles Limoges, Steve Moccaldi, Gerardo Orlando, and Brandon Yip. Charles Limoges, Steve Moccaldi, Gerardo Orlando, and Brandon Yip.
12. References 12. References
12.1. Normative References 12.1. Normative References
[RFC1033] Lottor, M., "Domain administrators operations guide", [RFC1033] Lottor, M., "Domain administrators operations guide",
RFC 1033, November 1987. RFC 1033, November 1987.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997. Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2578] McCloghrie, K., Ed., Perkins, D., Ed., and J. [RFC2578] McCloghrie, K., Ed., Perkins, D., Ed., and J.
Schoenwaelder, Ed., "Structure of Management Information Schoenwaelder, Ed., "Structure of Management Information
Version 2 (SMIv2)", STD 58, RFC 2578, April 1999. Version 2 (SMIv2)", STD 58, RFC 2578, April 1999.
[RFC2579] McCloghrie, K., Ed., Perkins, D., Ed., and J. [RFC2579] McCloghrie, K., Ed., Perkins, D., Ed., and J.
Schoenwaelder, Ed., "Textual Conventions for SMIv2", Schoenwaelder, Ed., "Textual Conventions for SMIv2",
STD 58, RFC 2579, April 1999. STD 58, RFC 2579, April 1999.
[RFC2580] McCloghrie, K., Perkins, D., and J. Schoenwaelder, [RFC2580] McCloghrie, K., Perkins, D., and J. Schoenwaelder,
"Conformance Statements for SMIv2", STD 58, RFC 2580, "Conformance Statements for SMIv2", STD 58, RFC 2580,
April 1999. April 1999.
[RFC3411] Harrington, D., Presuhn, R., and B. Wijnen, "An [RFC3411] Harrington, D., Presuhn, R., and B. Wijnen, "An
Architecture for Describing Simple Network Management Architecture for Describing Simple Network Management
Protocol (SNMP) Management Frameworks", STD 62, RFC 3411, Protocol (SNMP) Management Frameworks", STD 62,
December 2002. RFC 3411, December 2002.
[RFC3413] Levi, D., Meyer, P., and B. Stewart, "Simple Network [RFC3413] Levi, D., Meyer, P., and B. Stewart, "Simple Network
Management Protocol (SNMP) Applications", STD 62, Management Protocol (SNMP) Applications", STD 62,
RFC 3413, December 2002. RFC 3413, December 2002.
[RFC3414] Blumenthal, U. and B. Wijnen, "User-based Security Model [RFC3414] Blumenthal, U. and B. Wijnen, "User-based Security Model
(USM) for version 3 of the Simple Network Management (USM) for version 3 of the Simple Network Management
Protocol (SNMPv3)", STD 62, RFC 3414, December 2002. Protocol (SNMPv3)", STD 62, RFC 3414, December 2002.
[RFC3415] Wijnen, B., Presuhn, R., and K. McCloghrie, "View-based [RFC3415] Wijnen, B., Presuhn, R., and K. McCloghrie, "View-based
Access Control Model (VACM) for the Simple Network Access Control Model (VACM) for the Simple Network
Management Protocol (SNMP)", STD 62, RFC 3415, Management Protocol (SNMP)", STD 62, RFC 3415,
December 2002. December 2002.
[RFC3418] Presuhn, R., "Management Information Base (MIB) for the [RFC3418] Presuhn, R., "Management Information Base (MIB) for the
Simple Network Management Protocol (SNMP)", STD 62, Simple Network Management Protocol (SNMP)", STD 62,
RFC 3418, December 2002. RFC 3418, December 2002.
[RFC3490] Faltstrom, P., Hoffman, P., and A. Costello, [RFC3490] Faltstrom, P., Hoffman, P., and A. Costello,
"Internationalizing Domain Names in Applications (IDNA)", "Internationalizing Domain Names in Applications
RFC 3490, March 2003. (IDNA)", RFC 3490, March 2003.
[RFC3584] Frye, R., Levi, D., Routhier, S., and B. Wijnen, [RFC3584] Frye, R., Levi, D., Routhier, S., and B. Wijnen,
"Coexistence between Version 1, Version 2, and Version 3 "Coexistence between Version 1, Version 2, and Version 3
of the Internet-standard Network Management Framework", of the Internet-standard Network Management Framework",
BCP 74, RFC 3584, August 2003. BCP 74, RFC 3584, August 2003.
[RFC4347] Rescorla, E. and N. Modadugu, "Datagram Transport Layer [RFC4347] Rescorla, E. and N. Modadugu, "Datagram Transport Layer
Security", RFC 4347, April 2006. Security", RFC 4347, April 2006.
[RFC4366] Blake-Wilson, S., Nystrom, M., Hopwood, D., Mikkelsen, J., [RFC4366] Blake-Wilson, S., Nystrom, M., Hopwood, D., Mikkelsen,
and T. Wright, "Transport Layer Security (TLS) J., and T. Wright, "Transport Layer Security (TLS)
Extensions", RFC 4366, April 2006. Extensions", RFC 4366, April 2006.
[RFC5246] Dierks, T. and E. Rescorla, "The Transport Layer Security [RFC5246] Dierks, T. and E. Rescorla, "The Transport Layer
(TLS) Protocol Version 1.2", RFC 5246, August 2008. Security (TLS) Protocol Version 1.2", RFC 5246,
August 2008.
[RFC5280] Cooper, D., Santesson, S., Farrell, S., Boeyen, S., [RFC5280] Cooper, D., Santesson, S., Farrell, S., Boeyen, S.,
Housley, R., and W. Polk, "Internet X.509 Public Key Housley, R., and W. Polk, "Internet X.509 Public Key
Infrastructure Certificate and Certificate Revocation List Infrastructure Certificate and Certificate Revocation
(CRL) Profile", RFC 5280, May 2008. List (CRL) Profile", RFC 5280, May 2008.
[RFC5590] Harrington, D. and J. Schoenwaelder, "Transport Subsystem [RFC5590] Harrington, D. and J. Schoenwaelder, "Transport
for the Simple Network Management Protocol (SNMP)", Subsystem for the Simple Network Management Protocol
RFC 5590, June 2009. (SNMP)", RFC 5590, June 2009.
[RFC5591] Harrington, D. and W. Hardaker, "Transport Security Model [RFC5591] Harrington, D. and W. Hardaker, "Transport Security
for the Simple Network Management Protocol (SNMP)", Model for the Simple Network Management Protocol
RFC 5591, June 2009. (SNMP)", RFC 5591, June 2009.
[I-D.draft-ietf-6man-text-addr-representation] [RFC5952] Kawamura, S. and M. Kawashima, "A Recommendation for
Kawamura, S. and M. Kawashima, "A Recommendation for IPv6 IPv6 Address Text Representation", RFC 5952,
Address Text Representation". August 2010.
12.2. Informative References 12.2. Informative References
[RFC3410] Case, J., Mundy, R., Partain, D., and B. Stewart, [RFC3410] Case, J., Mundy, R., Partain, D., and B. Stewart,
"Introduction and Applicability Statements for Internet- "Introduction and Applicability Statements for Internet-
Standard Management Framework", RFC 3410, December 2002. Standard Management Framework", RFC 3410, December 2002.
[RFC5343] Schoenwaelder, J., "Simple Network Management Protocol [RFC5343] Schoenwaelder, J., "Simple Network Management Protocol
(SNMP) Context EngineID Discovery", RFC 5343, (SNMP) Context EngineID Discovery", RFC 5343,
September 2008. September 2008.
[RFC5592] Harrington, D., Salowey, J., and W. Hardaker, "Secure [RFC5592] Harrington, D., Salowey, J., and W. Hardaker, "Secure
Shell Transport Model for the Simple Network Management Shell Transport Model for the Simple Network Management
Protocol (SNMP)", RFC 5592, June 2009. Protocol (SNMP)", RFC 5592, June 2009.
[I-D.seggelmann-tls-dtls-heartbeat] [HEARTBEAT] Seggelmann, R., Tuexen, M., and M. Williams, "Transport
Seggelmann, R., Tuexen, M., and M. Williams, "Transport Layer Security and Datagram Transport Layer Security
Layer Security and Datagram Transport Layer Security Heartbeat Extension", Work in Progress, February 2010.
Heartbeat Extension".
Appendix A. Target and Notification Configuration Example Appendix A. Target and Notification Configuration Example
The following sections describe example configuration for the SNMP- The following sections describe example configuration for the SNMP-
TLS-TM-MIB, the SNMP-TARGET-MIB, the NOTIFICATION-MIB and the SNMP- TLS-TM-MIB, the SNMP-TARGET-MIB, the NOTIFICATION-MIB, and the SNMP-
VIEW-BASED-ACM-MIB. VIEW-BASED-ACM-MIB.
A.1. Configuring a Notification Originator A.1. Configuring a Notification Originator
The following row adds the "Joe Cool" user to the "administrators" The following row adds the "Joe Cool" user to the "administrators"
group: group:
vacmSecurityModel = 4 (TSM) vacmSecurityModel = 4 (TSM)
vacmSecurityName = "Joe Cool" vacmSecurityName = "Joe Cool"
vacmGroupName = "administrators" vacmGroupName = "administrators"
skipping to change at page 63, line 11 skipping to change at page 63, line 38
snmpTlstmAddrServerFingerprint = "" snmpTlstmAddrServerFingerprint = ""
snmpTlstmAddrServerIdentity = "server.example.org" snmpTlstmAddrServerIdentity = "server.example.org"
snmpTlstmAddrStorageType = 3 (nonVolatile) snmpTlstmAddrStorageType = 3 (nonVolatile)
snmpTlstmAddrRowStatus = 4 (createAndGo) snmpTlstmAddrRowStatus = 4 (createAndGo)
The following row configures the snmpTargetAddrTable to send The following row configures the snmpTargetAddrTable to send
notifications using TLS/TCP to the snmptls-trap port at 192.0.2.1: notifications using TLS/TCP to the snmptls-trap port at 192.0.2.1:
snmpTargetAddrName = "toNRAddr" snmpTargetAddrName = "toNRAddr"
snmpTargetAddrTDomain = snmpTLSTCPDomain snmpTargetAddrTDomain = snmpTLSTCPDomain
snmpTargetAddrTAddress = "192.0.2.1:XXXsnmptls-trap" snmpTargetAddrTAddress = "192.0.2.1:10162"
snmpTargetAddrTimeout = 1500 snmpTargetAddrTimeout = 1500
snmpTargetAddrRetryCount = 3 snmpTargetAddrRetryCount = 3
snmpTargetAddrTagList = "toNRTag" snmpTargetAddrTagList = "toNRTag"
snmpTargetAddrParams = "toNR" (MUST match above) snmpTargetAddrParams = "toNR" (MUST match below)
snmpTargetAddrStorageType = 3 (nonVolatile) snmpTargetAddrStorageType = 3 (nonVolatile)
snmpTargetAddrColumnStatus = 4 (createAndGo) snmpTargetAddrColumnStatus = 4 (createAndGo)
RFC Editor's note: replace the string "XXXsnmptls-trap" above with
the appropriately assigned "snmptls-trap" port.
The following row configures the snmpTargetParamsTable to send the The following row configures the snmpTargetParamsTable to send the
notifications to "Joe Cool", using authPriv SNMPv3 notifications notifications to "Joe Cool", using authPriv SNMPv3 notifications
through the TransportSecurityModel [RFC5591]: through the TransportSecurityModel [RFC5591]:
snmpTargetParamsName = toNR snmpTargetParamsName = "toNR" (must match above)
snmpTargetParamsMPModel = SNMPv3 snmpTargetParamsMPModel = 3 (SNMPv3)
snmpTargetParamsSecurityModel = 4 (TransportSecurityModel) snmpTargetParamsSecurityModel = 4 (TransportSecurityModel)
snmpTargetParamsSecurityName = "Joe Cool" snmpTargetParamsSecurityName = "Joe Cool"
snmpTargetParamsSecurityLevel = 3 (authPriv) snmpTargetParamsSecurityLevel = 3 (authPriv)
snmpTargetParamsStorageType = 3 (nonVolatile) snmpTargetParamsStorageType = 3 (nonVolatile)
snmpTargetParamsRowStatus = 4 (createAndGo0 snmpTargetParamsRowStatus = 4 (createAndGo0
A.2. Configuring TLSTM to Utilize a Simple Derivation of tmSecurityName A.2. Configuring TLSTM to Utilize a Simple Derivation of tmSecurityName
The following row configures the snmpTlstmCertToTSNTable to map a The following row configures the snmpTlstmCertToTSNTable to map a
validated client certificate, referenced by the client's public X.509 validated client certificate, referenced by the client's public X.509
skipping to change at page 64, line 6 skipping to change at page 64, line 29
snmpTlstmCertToTSNID = 1 snmpTlstmCertToTSNID = 1
(chosen by ordering preference) (chosen by ordering preference)
snmpTlstmCertToTSNFingerprint = HASH (appropriate fingerprint) snmpTlstmCertToTSNFingerprint = HASH (appropriate fingerprint)
snmpTlstmCertToTSNMapType = snmpTlstmCertSANAny snmpTlstmCertToTSNMapType = snmpTlstmCertSANAny
snmpTlstmCertToTSNData = "" (not used) snmpTlstmCertToTSNData = "" (not used)
snmpTlstmCertToTSNStorageType = 3 (nonVolatile) snmpTlstmCertToTSNStorageType = 3 (nonVolatile)
snmpTlstmCertToTSNRowStatus = 4 (createAndGo) snmpTlstmCertToTSNRowStatus = 4 (createAndGo)
This type of configuration should only be used when the naming This type of configuration should only be used when the naming
conventions of the (possibly multiple) certificate authorities are conventions of the (possibly multiple) Certification Authorities are
well understood, so two different principals cannot inadvertently be well understood, so two different principals cannot inadvertently be
identified by the same derived tmSecurityName. identified by the same derived tmSecurityName.
A.3. Configuring TLSTM to Utilize Table-Driven Certificate Mapping A.3. Configuring TLSTM to Utilize Table-Driven Certificate Mapping
The following row configures the snmpTlstmCertToTSNTable to map a The following row configures the snmpTlstmCertToTSNTable to map a
validated client certificate, referenced by the client's public X.509 validated client certificate, referenced by the client's public X.509
hash fingerprint, to the directly specified tmSecurityName of "Joe hash fingerprint, to the directly specified tmSecurityName of "Joe
Cool". Cool".
snmpTlstmCertToTSNID = 1 snmpTlstmCertToTSNID = 2
(chosen by ordering preference) (chosen by ordering preference)
snmpTlstmCertToTSNFingerprint = HASH (appropriate fingerprint) snmpTlstmCertToTSNFingerprint = HASH (appropriate fingerprint)
snmpTlstmCertToTSNMapType = snmpTlstmCertSpecified snmpTlstmCertToTSNMapType = snmpTlstmCertSpecified
snmpTlstmCertToTSNSecurityName = "Joe Cool" snmpTlstmCertToTSNSecurityName = "Joe Cool"
snmpTlstmCertToTSNStorageType = 3 (nonVolatile) snmpTlstmCertToTSNStorageType = 3 (nonVolatile)
snmpTlstmCertToTSNRowStatus = 4 (createAndGo) snmpTlstmCertToTSNRowStatus = 4 (createAndGo)
Author's Address Author's Address
Wes Hardaker Wes Hardaker
Sparta, Inc. SPARTA, Inc.
P.O. Box 382 P.O. Box 382
Davis, CA 95617 Davis, CA 95617
USA USA
Phone: +1 530 792 1913 Phone: +1 530 792 1913
Email: ietf@hardakers.net EMail: ietf@hardakers.net
 End of changes. 211 change blocks. 
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