Network Working Group M. Bjorklund
Internet-Draft Tail-f Systems
Intended status: Standards Track J. Schoenwaelder
Expires: March 22, 2015 Jacobs University
September 18, 2014

A YANG Data Model for SNMP Configuration
draft-ietf-netmod-snmp-cfg-08

Abstract

This document defines a collection of YANG definitions for configuring SNMP engines.

Status of This Memo

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

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

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

This Internet-Draft will expire on March 22, 2015.

Copyright Notice

Copyright (c) 2014 IETF Trust and the persons identified as the document authors. All rights reserved.

This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License.


Table of Contents

1. Introduction

This document defines a YANG [RFC6020] data model for the configuration of SNMP engines. The configuration model is consistent with the MIB modules defined in [RFC3411], [RFC3412], [RFC3413], [RFC3414], [RFC3415], [RFC3418], [RFC3584], [RFC5591], [RFC5592], and [RFC6353] but takes advantage of YANG's ability to define hierarchical configuration data models.

The configuration data model in particular has been designed for SNMP deployments where SNMP runs in read-only mode and NETCONF is used to configure the SNMP agent. Nevertheless, the data model allows implementations that support write access both via SNMP and NETCONF in order to interwork with SNMP-managed management applications manipulating SNMP agent configuration using SNMP. Further details can be found in Section 3.

The YANG data model focuses on configuration. Operational state objects are not explicitely modeled. The operational state of an SNMP agent can either be accessed directly via SNMP or, alternatively, via NETCONF using the read-only translation of the relevant SNMP MIB modules into YANG modules [RFC6643].

This document also defines a YANG data model for mapping a X.509 certificate to a name.

The keywords "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in BCP 14, [RFC2119].

2. Data Model

In order to preserve the modularity of SNMP, the YANG configuration data model is organized in a set of YANG submodules, all sharing the same module namespace. This allows adding configuration support for additional SNMP features while keeping the number of namespaces that have to be dealt with down to a minimum.

2.1. Tree Diagrams

A simplified graphical representation of the data model is used in this document. The meaning of the symbols in these diagrams is as follows:

2.2. General Considerations

Most YANG nodes are mapped 1-1 to the corresponding MIB object. The "reference" statement is used to indicate which corresponding MIB object the YANG node is mapped to. When there is not a simple 1-1 mapping, the "description" statement explains the mapping.

The persistency models in SNMP and NETCONF are quite different. In NETCONF, the persistency is defined by the datastore, whereas in SNMP it is defined either explicitly in the data model, or on a row-by-row basis by using the TEXTUAL-CONVENTION "StorageType". Thus, in the YANG model defined here, the "StorageType" columns are not present. For implementation guidelines, see Section 3.

In SNMP, row creation and deletion are controlled by using the TEXTUAL-CONVENTION "RowStatus". In NETCONF, creation and deletion are handled by the protocol, not in the data model. Thus, in the YANG model defined here, the "RowStatus" columns are not present.

2.3. Common Definitions

The submodule "ietf‑snmp‑common" defines a set of common typedefs and the top-level container "snmp". All configuration parameters defined in the other submodules are organized under this top-level container.

2.4. Engine Configuration

The submodule "ietf‑snmp‑engine", which defines configuration parameters that are specific to SNMP engines, has the following structure:

   +--rw snmp
      +--rw engine
         +--rw enabled?               boolean
         +--rw listen* [name]
         |  +--rw name    snmp:identifier
         |  +--rw (transport)
         |     +--:(udp)
         |        +--rw udp
         |           +--rw ip      inet:ip-address
         |           +--rw port?   inet:port-number
         +--rw version
         |  +--rw v1?    empty
         |  +--rw v2c?   empty
         |  +--rw v3?    empty
         +--rw engine-id?             snmp:engine-id
         +--rw enable-authen-traps?   boolean
	    

The leaf "/snmp/engine/enabled" can be used to enable/disable an SNMP engine.

The list "/snmp/engine/listen" provides configuration of the transport endpoints the engine is listening to. In this submodule, SNMP over UDP is defined. SSH, TLS and Datagram Transport Layer Security (DTLS) are also supported, defined in "ietf‑snmp‑ssh" (Section 2.13) and "ietf‑snmp‑tls" (Section 2.12), respectively. The "transport" choice is expected to be augmented for other transports.

The "/snmp/engine/version" container can be used to enable/disable the different message processing models [RFC3411].

2.5. Target Configuration

The submodule "ietf‑snmp‑target", which defines configuration parameters that correspond to the objects in SNMP-TARGET-MIB, has the following structure:

   +--rw snmp
      +--rw target* [name]
      |  +--rw name       snmp:identifier
      |  +--rw (transport)
      |  |  +--:(udp)
      |  |     +--rw udp
      |  |        +--rw ip               inet:ip-address
      |  |        +--rw port?            inet:port-number
      |  |        +--rw prefix-length?   uint8
      |  +--rw tag*       snmp:identifier
      |  +--rw timeout?   uint32
      |  +--rw retries?   uint8
      |  +--rw target-params  snmp:identifier
      +--rw target-params* [name]
         +--rw name    snmp:identifier
         +--rw (params)?
	    

An entry in the list "/snmp/target" corresponds to an "snmpTargetAddrEntry".

The "snmpTargetAddrTDomain" and "snmpTargetAddrTAddress" objects are mapped to transport-specific YANG nodes. Each transport is configured as a separate case in the "transport" choice. In this submodule, SNMP over UDP is defined. TLS and DTLS are also supported, defined in "ietf‑snmp‑tls" (Section 2.12). The "transport" choice is expected to be augmented for other transports.

An entry in the list "/snmp/target‑params" corresponds to an "snmpTargetParamsEntry". This list contains a choice "params", which is augmented by security model specific submodules, currently "ietf‑snmp‑community" (Section 2.8), "ietf‑snmp‑usm" (Section 2.10), and "ietf‑snmp‑tls" (Section 2.12).

2.6. Notification Configuration

The submodule "ietf‑snmp‑notification", which defines configuration parameters that correspond to the objects in SNMP-NOTIFICATION-MIB, has the following structure:

   +--rw snmp
      +--rw notify* [name]
      |  +--rw name    snmp:identifier
      |  +--rw tag     snmp:identifier
      |  +--rw type?   enumeration
      +--rw notify-filter-profile* [name]
         +--rw name       snmp:identifier
         +--rw include*   snmp:wildcard-object-identifier
         +--rw exclude*   snmp:wildcard-object-identifier
	    

It also augments the "target‑params" list defined in the "ietf‑snmp‑target" submodule (Section 2.5) with one leaf:

   +--rw snmp
      +--rw target-params* [name]
         ...
         +--rw notify-filter-profile?   leafref
	    

An entry in the list "/snmp/notify" corresponds to an "snmpNotifyEntry".

An entry in the list "/snmp/notify‑filter‑profile" corresponds to an "snmpNotifyFilterProfileEntry". In the MIB, there is a sparse relationship between "snmpTargetParamsTable" and "snmpNotifyFilterProfileTable". In the YANG model, this sparse relationship is represented with a leafref leaf "notify‑filter‑profile" in the "/snmp/target‑params" list, which refers to an entry in the "/snmp/notify‑filter‑profile" list.

The "snmpNotifyFilterTable" is represented as a list "filter" within the "/snmp/notify‑filter‑profile" list.

This submodule defines the feature "notification‑filter". A server implements this feature if it supports SNMP notification filtering [RFC3413].

2.7. Proxy Configuration

The submodule "ietf‑snmp‑proxy", which defines configuration parameters that correspond to the objects in SNMP-PROXY-MIB, has the following structure:

   +--rw snmp
      +--rw proxy* [name]
         +--rw name                    snmp:identifier
         +--rw type                    enumeration
         +--rw context-engine-id       snmp:engine-id
         +--rw context-name?           snmp:context-name
         +--rw target-params-in?       snmp:identifier
         +--rw single-target-out?      snmp:identifier
         +--rw multiple-target-out?    snmp:identifier
	    

An entry in the list "/snmp/proxy" corresponds to an "snmpProxyEntry".

This submodule defines the feature "proxy". A server implements this feature if it can act as an SNMP Proxy [RFC3413].

2.8. Community Configuration

The submodule "ietf‑snmp‑community", which defines configuration parameters that correspond to the objects in SNMP-COMMUNITY-MIB, has the following structure:

   +--rw snmp
      +--rw community* [index]
         +--rw index            snmp:identifier
         +--rw (name)?
         |  +--:(text-name)
         |  |  +--rw text-name?       string
         |  +--:(binary-name)
         |     +--rw binary-name?     binary
         +--rw security-name    snmp:security-name
         +--rw engine-id?       snmp:engine-id
         +--rw context?         snmp:context-name
         +--rw target-tag?      snmp:identifier
	    

It also augments the "/snmp/target‑params/params" choice with nodes for the Community-Based Security Model used by SNMPv1 and SNMPv2c:

   +--rw snmp
      +--rw target-params* [name]
      |  ...
      |  +--rw (params)?
      |     +--:(v1)
      |     |  +--rw v1
      |     |     +--rw security-name    snmp:security-name
      |     +--:(v2c)
      |        +--rw v2c
      |           +--rw security-name    snmp:security-name
      +--rw target* [name]
         +--rw mms?       union
	    

An entry in the list "/snmp/community" corresponds to an "snmpCommunityEntry".

When a case "v1" or "v2c" is chosen, it implies a snmpTargetParamsMPModel 0 (SNMPv1) or 1 (SNMPv2), and a snmpTargetParamsSecurityModel 1 (SNMPv1) or 2 (SNMPv2), respectively. Both cases implies a snmpTargetParamsSecurityLevel of noAuthNoPriv.

2.9. View-based Access Control Model Configuration

The submodule "ietf‑snmp‑vacm", which defines configuration parameters that correspond to the objects in SNMP-VIEW-BASED-ACM-MIB, has the following structure:

   +--rw snmp
      +--rw vacm
         +--rw group* [name]
         |  +--rw name      group-name
         |  +--rw member* [security-name]
         |  |  +--rw security-name     snmp:security-name
         |  |  +--rw security-model*   snmp:security-model
         |  +--rw access* [context security-model security-level]
         |     +--rw context           snmp:context-name
         |     +--rw context-match?    enumeration
         |     +--rw security-model    snmp:security-model-or-any
         |     +--rw security-level    snmp:security-level
         |     +--rw read-view?        view-name
         |     +--rw write-view?       view-name
         |     +--rw notify-view?      vire-name
         +--rw view* [name]
            +--rw name       view-name
            +--rw include*   snmp:wildcard-object-identifier
            +--rw exclude*   snmp:wildcard-object-identifier
	    

The "vacmSecurityToGroupTable" and "vacmAccessTable" are mapped to a structure of nested lists in the YANG model. Groups are defined in the list "/snmp/vacm/group" and for each group there is a sublist "member" that maps to "vacmSecurityToGroupTable", and a sublist "access" that maps to "vacmAccessTable".

MIB views are defined in the list "/snmp/vacm/view" and for each MIB view there is a leaf-list of included subtree families and a leaf-list of excluded subtree families. This is more compact and thus a more readable representation of the "vacmViewTreeFamilyTable".

2.10. User-based Security Model Configuration

The submodule "ietf‑snmp‑usm", which defines configuration parameters that correspond to the objects in SNMP-USER-BASED-SM-MIB, has the following structure:

   +--rw snmp
      +--rw usm
         +--rw local
         |  +--rw user* [name]
         |     +-- {common user params}
         +--rw remote* [engine-id]
            +--rw engine-id    snmp:engine-id
            +--rw user* [name]
               +-- {common user params}
	    

The "{common user params}" are:

   +--rw name    snmp:identifier
   +--rw auth!
   |  +--rw (protocol)
   |     +--:(md5)
   |     |  +--rw md5
   |     |     +-- rw key    yang:hex-string
   |     +--:(sha)
   |        +--rw sha
   |           +-- rw key    yang:hex-string
   +--rw priv!
      +--rw (protocol)
         +--:(des)
         |  +--rw des
         |     +-- rw key    yang:hex-string
         +--:(aes)
            +--rw aes
               +-- rw key    yang:hex-string
	    

It also augments the "/snmp/target‑params/params" choice with nodes for the SNMP User-based Security Model.

   +--rw snmp
      +--rw target-params* [name]
         ...
         +--rw (params)?
            +--:(usm)
               +--rw usm
                  +--rw user-name         snmp:security-name
                  +--rw security-level    security-level
	    

In the MIB, there is a single table with local and remote users, indexed by the engine id and user name. In the YANG model, there is one list of local users, and a nested list of remote users.

In the MIB, there are several objects related to changing the authentication and privacy keys. These objects are not present in the YANG model. However, the localized key can be changed. This implies that if the engine id is changed, all users keys need to be changed as well.

2.11. Transport Security Model Configuration

The submodule "ietf‑snmp‑tsm", which defines configuration parameters that correspond to the objects in SNMP-TSM-MIB, has the following structure:

   +--rw snmp
      +--rw tsm
         +--rw use-prefix?   boolean
	    

It also augments the "/snmp/target‑params/params" choice with nodes for the SNMP Transport Security Model.

   +--rw snmp
      +--rw target-params* [name]
         ...
         +--rw (params)?
            +--:(tsm)
               +--rw tsm
                  +--rw security-name     snmp:security-name
                  +--rw security-level    security-level
	    

This submodule defines the feature "tsm". A server implements this feature if it supports the Transport Security Model (tsm) [RFC5591].

2.12. Transport Layer Security Transport Model Configuration

The submodule "ietf‑snmp‑tls", which defines configuration parameters that correspond to the objects in SNMP-TLS-TM-MIB, has the following structure:

   +--rw snmp
      ...
      +--rw target* [name]
      |  ...
      |  +--rw (transport)
      |     ...
      |     +--:(tls)
      |     |  +--rw tls
      |     |     +-- {common (d)tls transport params}
      |     +--:(dtls)
      |        +--rw dtls
      |           +-- {common (d)tls transport params}
      +--rw tlstm
         +--rw cert-to-name* [id]
            +--rw id             uint32
            +--rw fingerprint    x509c2n:tls-fingerprint
            +--rw map-type       identityref
            +--rw name           string
	    

The "{common (d)tls transport params}" are:

   +--rw ip?                   inet:host
   +--rw port?                 inet:port-number
   +--rw client-fingerprint?   x509c2n:tls-fingerprint
   +--rw server-fingerprint?   x509c2n:tls-fingerprint
   +--rw server-identity?      snmp:admin-string
	    

It also augments the "/snmp/engine/listen/transport" choice with objects for the D(TLS) transport endpoints:

   +--rw snmp
      +--rw engine
         ...
         +--rw listen* [name]
            ...
            +--rw (transport)
               ...
               +--:(tls)
               |  +--rw tls
               |     +--rw ip      inet:ip-address
               |     +--rw port?   inet:port-number
               +--:(dtls)
                  +--rw dtls
                     +--rw ip      inet:ip-address
                     +--rw port?   inet:port-number
	    

This submodule defines the feature "tlstm". A server implements this feature if it supports the Transport Layer Security (TLS) Transport Model (tlstm) [RFC6353].

2.13. Secure Shell Transport Model Configuration

The submodule "ietf‑snmp‑ssh", which defines configuration parameters that correspond to the objects in SNMP-SSH-TM-MIB, has the following structure:

   +--rw snmp
      ...
      +--rw target* [name]
        ...
        +--rw (transport)
           ...
           +--:(ssh)
              +--rw ssh
                 +--rw ip          inet:host
                 +--rw port?       inet:port-number
                 +--rw username?   string
	    

It also augments the "/snmp/engine/listen/transport" choice with objects for the SSH transport endpoints:

   +--rw snmp
      +--rw engine
         ...
         +--rw listen* [name]
            ...
            +--rw (transport)
               ...
               +--:(ssh)
                  +--rw ssh
                     +--rw ip          inet:host
                     +--rw port?       inet:port-number
                     +--rw username?   string
	    

This submodule defines the feature "sshtm". A server implements this feature if it supports the Secure Shell (SSH) Transport Model (sshtm) [RFC5592].

3. Implementation Guidelines

This section describes some challenges for implementations that support both the YANG models defined in this document, and either read-write or read-only SNMP access to the same data, using the standard MIB modules.

As described in Section 2.2, the persistency models in NETCONF and SNMP are quite different. This poses a challenge for an implementation to support both NETCONF and SNMP access to the same data, in particular if the data is writable over both protocols. Specifically, the configuration data may exist in some combination of the three NETCONF configuration datastores, and this data must be mapped to rows in the SNMP tables, in some SNMP contexts, with proper values for the StorageType columns.

This problem is not new; it has been handled in many implementations that support configuration of the SNMP engine over a command line interface (CLI), which normally have a persistency model similar to NETCONF.

Since there is not one solution that works for all cases, this document does not provide a recommended solution. Instead some of the challenges involved are described below.

3.1. Supporting read-only SNMP Access

If a device implements only :writable-running, it is trivial to map the contents of "running" to data in the SNMP tables, where all instances of the StorageType columns have the value "nonVolatile".

If a device implements :candidate, but not :startup, the implementation may choose to not expose the contents of the "candidate" datastore over SNMP, and map the contents of "running" as described above. As an option, the contents of "candidate" might be accessible in a separate SNMP context.

If a device implements :startup, the handling of StorageType becomes more difficult. Since the contents of "running" and "startup" might differ, data in running cannot automatically be mapped to instances with StorageType "nonVolatile". If a particular entry exists in "running" but not in "startup", its StorageType should be "volatile". If a particular entry exists in "startup", but not "running", it should not be mapped to an SNMP instance, at least not in the default SNMP context.

3.2. Supporting read-write SNMP access

If the implementation supports read-write access to data over SNMP, and specifically creation of table rows, special attention has to be given the handling of the RowStatus and StorageType columns. The problem is to determine which table rows to store in the configuration datastores, and which configuration datastore is appropriate for each row.

The SNMP tables contain a mix of configured data and operational state, and only rows with an "active" RowStatus column should be stored in a configuration datastore.

If a device implements only :writable-running, "active" rows with a "nonVolatile" StorageType column can be stored in "running". Rows with a "volatile" StorageType column are operational state.

If a device implements :candidate, but not :writable-running, all configuration changes typically go through the "candidate", even if they are done over SNMP. An implementation might have to perform some automatic commit of the "candidate" when data is written over SNMP, since there is no explicit "commit" operation in SNMP.

If a device implements :startup, "nonVolatile" rows cannot just be written to "running", they must also be copied into "startup". "volatile" rows may be treated as operational state and not copied to any datastore, or copied into "running".

Cooperating SNMP management applications may use spin lock objects (snmpTargetSpinLock [RFC3413], usmUserSpinLock [RFC3414], vacmViewSpinLock [RFC3415]) to coordinate concurrent write requests. Implementations supporting modifications of MIB objects protected by a spin lock via NETCONF should ensure that the spin lock objects are properly incremented whenever objects are changed via NETCONF. This allows cooperating SNMP management applications to discover that concurrent modifications are taking place.

4. Definitions

4.1. Module 'ietf-x509-cert-to-name'

This YANG module imports typedefs from [RFC6991].

<CODE BEGINS> file "ietf-x509-cert-to-name.yang"

module ietf-x509-cert-to-name {

  namespace "urn:ietf:params:xml:ns:yang:ietf-x509-cert-to-name";
  prefix x509c2n;

  import ietf-yang-types {
    prefix yang;
  }

  organization
    "IETF NETMOD (NETCONF Data Modeling Language) Working Group";

  contact
    "WG Web:   <http://tools.ietf.org/wg/netmod/>
     WG List:  <mailto:netmod@ietf.org>

     WG Chair: Thomas Nadeau
               <mailto:tnadeau@lucidvision.com>

     WG Chair: Juergen Schoenwaelder
               <mailto:j.schoenwaelder@jacobs-university.de>

     Editor:   Martin Bjorklund
               <mailto:mbj@tail-f.com>

     Editor:   Juergen Schoenwaelder
               <mailto:j.schoenwaelder@jacobs-university.de>";

  description
    "This module contains a collection of YANG definitions for
     extracting a name from a X.509 certificate.

     The algorithm used to extract a name from a X.509 certificate
     was first defined in RFC 6353.

     Copyright (c) 2014 IETF Trust and the persons identified as
     authors of the code.  All rights reserved.

     Redistribution and use in source and binary forms, with or
     without modification, is permitted pursuant to, and subject
     to the license terms contained in, the Simplified BSD License
     set forth in Section 4.c of the IETF Trust's Legal Provisions
     Relating to IETF Documents
     (http://trustee.ietf.org/license-info).

     This version of this YANG module is part of RFC XXXX; see
     the RFC itself for full legal notices.";
  // RFC Ed.: replace XXXX with actual RFC number and remove this
  // note.

  reference
    "RFC6353: Transport Layer Security (TLS) Transport Model for
              the Simple Network Management Protocol (SNMP)";

  // RFC Ed.: update the date below with the date of RFC publication
  // and remove this note.

  revision 2014-05-06 {
    description
      "Initial revision.";
    reference
      "RFC XXXX: A YANG Data Model for SNMP Configuration";

  }

  typedef tls-fingerprint {
    type yang:hex-string {
      pattern '([0-9a-fA-F]){2}(:([0-9a-fA-F]){2}){0,254}';
    }
    description
     "A fingerprint value that can be used to uniquely reference
      other data of potentially arbitrary length.

      An tls-fingerprint value is composed of a 1-octet hashing
      algorithm identifier followed by the fingerprint value.  The
      first octet value identifying the hashing algorithm is taken
      from the IANA TLS HashAlgorithm Registry (RFC 5246).  The
      remaining octets are filled using the results of the hashing
      algorithm.";
    reference "SNMP-TLS-TM-MIB.SnmpTLSFingerprint";
  }

  /* Identities */

  identity cert-to-name {
    description
      "Base identity for algorithms to derive a name from a
       certificate.";
  }

  identity specified {
    base cert-to-name;
    description
      "Directly specifies the name to be used for the certificate.
       The value of the leaf 'name' in 'cert-to-name' list is used.";
    reference "SNMP-TLS-TM-MIB.snmpTlstmCertSpecified";
  }

  identity san-rfc822-name {
    base cert-to-name;
    description
      "Maps a subjectAltName's rfc822Name to a name.  The local part
       of the rfc822Name is passed unaltered but the host-part of the
       name must be passed in lowercase.  For example, the
       rfc822Name field FooBar@Example.COM is mapped to name
       FooBar@example.com.";
    reference "SNMP-TLS-TM-MIB.snmpTlstmCertSANRFC822Name";
  }

  identity san-dns-name {
    base cert-to-name;
    description
      "Maps a subjectAltName's dNSName to a name after first
       converting it to all lowercase (RFC 5280 does not specify
       converting to lowercase so this involves an extra step).
       This mapping results in a 1:1 correspondence between
       subjectAltName dNSName values and the name values.";
    reference "SNMP-TLS-TM-MIB.snmpTlstmCertSANDNSName";
  }

  identity san-ip-address {
    base cert-to-name;
    description
      "Maps a subjectAltName's iPAddress to a name by
       transforming the binary encoded address as follows:

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

         2) for IPv6 addresses, the value is converted into a
            32-character all lowercase hexadecimal string
            without any colon separators.

       This mapping results in a 1:1 correspondence between
       subjectAltName iPAddress values and the name values.";
    reference "SNMP-TLS-TM-MIB.snmpTlstmCertSANIpAddress";
  }

  identity san-any {
    base cert-to-name;
    description
      "Maps any of the following fields using the corresponding
       mapping algorithms:

         +------------+-----------------+
         | Type       | Algorithm       |
         |------------+-----------------|
         | rfc822Name | san-rfc822-name |
         | dNSName    | san-dns-name    |
         | iPAddress  | san-ip-address  |
         +------------+-----------------+

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

       This mapping results in a 1:1 correspondence between
       subjectAltName values and name values.  The three sub-mapping
       algorithms produced by this combined algorithm cannot produce
       conflicting results between themselves.";
    reference "SNMP-TLS-TM-MIB.snmpTlstmCertSANAny";
  }

  identity common-name {
    base cert-to-name;
    description
      "Maps a certificate's CommonName to a name after converting
       it to a UTF-8 encoding.  The usage of CommonNames is
       deprecated and users are encouraged to use subjectAltName
       mapping methods instead.  This mapping results in a 1:1
       correspondence between certificate CommonName values and name
       values.";
    reference "SNMP-TLS-TM-MIB.snmpTlstmCertCommonName";
  }

  /*
   * Groupings
   */

  grouping cert-to-name {
    description
      "Defines nodes for mapping certificates to names.  Modules
       that uses this grouping should describe how the resulting
       name is used.";

    list cert-to-name {
      key id;
      description
        "This list defines how certificates are mapped to names.
         The name is derived by considering each cert-to-name
         list entry in order. The cert-to-name entry's fingerprint
         determines whether the list entry is a match:

         1) If the cert-to-name list entry's fingerprint value
            matches that of the presented certificate, then consider
            the list entry as a successful match.

         2) If the cert-to-name list entry's fingerprint value
            matches that of a locally held copy of a trusted CA
            certificate, and that CA certificate was part of the CA
            certificate chain to the presented certificate, then
            consider the list entry as a successful match.

        Once a matching cert-to-name list entry has been found, the
        map-type is used to determine how the name associated with
        the certificate should be determined.  See the map-type
        leaf's description for details on determining the name value.
        If it is impossible to determine a name from the cert-to-name
        list entry's data combined with the data presented in the
        certificate, then additional cert-to-name list entries MUST
        be searched looking for another potential match.

        Security administrators are encouraged to make use of
        certificates with subjectAltName fields that can be mapped to
        names so that a single root CA certificate can allow all
        child certificate's subjectAltName to map directly to a name
        via a 1:1 transformation.";
      reference "SNMP-TLS-TM-MIB.snmpTlstmCertToTSNEntry";

      leaf id {
        type uint32;
        description
          "The id specifies the order in which the entries in the
           cert-to-name list are searched.  Entries with lower
           numbers are searched first.";
        reference "SNMP-TLS-TM-MIB.snmpTlstmCertToTSNID";
      }

      leaf fingerprint {
        type x509c2n:tls-fingerprint;
        mandatory true;
        description
          "Specifies a value with which the fingerprint of the
           full certificate presented by the peer is compared.  If
           the fingerprint of the full certificate presented by the
           peer does not match the fingerprint configured, then the
           entry is skipped and the search for a match continues.";
        reference "SNMP-TLS-TM-MIB.snmpTlstmCertToTSNFingerprint";
      }

      leaf map-type {
        type identityref {
          base cert-to-name;
        }
        mandatory true;
        description
          "Specifies the algorithm used to map the certificate
           presented by the peer to a name.

           Mappings that need additional configuration objects should
           use the 'when' statement to make them conditional based on
           the 'map-type'.";
        reference "SNMP-TLS-TM-MIB.snmpTlstmCertToTSNMapType";
      }

      leaf name {
        when "../map-type = 'x509c2n:specified'";
        type string;
        mandatory true;
        description
          "Directly specifies the NETCONF username when the
           'map-type' is 'specified'.";
        reference "SNMP-TLS-TM-MIB.snmpTlstmCertToTSNData";
      }
    }
  }
}
	    

<CODE ENDS>

4.2. Module 'ietf-snmp'

<CODE BEGINS> file "ietf-snmp.yang"

module ietf-snmp {

  namespace "urn:ietf:params:xml:ns:yang:ietf-snmp";
  prefix snmp;

  // RFC Ed.: update the dates below with the date of RFC publication
  // and remove this note.

  include ietf-snmp-common {
    revision-date 2014-05-06;
  }
  include ietf-snmp-engine {
    revision-date 2014-05-06;
  }
  include ietf-snmp-target {
    revision-date 2014-05-06;
  }
  include ietf-snmp-notification {
    revision-date 2014-05-06;
  }
  include ietf-snmp-proxy {
    revision-date 2014-05-06;
  }
  include ietf-snmp-community {
    revision-date 2014-05-06;
  }
  include ietf-snmp-usm {
    revision-date 2014-05-06;
  }
  include ietf-snmp-tsm {
    revision-date 2014-05-06;
  }
  include ietf-snmp-vacm {
    revision-date 2014-05-06;
  }
  include ietf-snmp-tls {
    revision-date 2014-05-06;
  }
  include ietf-snmp-ssh {
    revision-date 2014-05-06;
  }

  organization
    "IETF NETMOD (NETCONF Data Modeling Language) Working Group";

  contact
    "WG Web:   <http://tools.ietf.org/wg/netmod/>
     WG List:  <mailto:netmod@ietf.org>

     WG Chair: Thomas Nadeau
               <mailto:tnadeau@lucidvision.com>

     WG Chair: Juergen Schoenwaelder
               <mailto:j.schoenwaelder@jacobs-university.de>

     Editor:   Martin Bjorklund
               <mailto:mbj@tail-f.com>

     Editor:   Juergen Schoenwaelder
               <mailto:j.schoenwaelder@jacobs-university.de>";

  description
    "This module contains a collection of YANG definitions for
     configuring SNMP engines.

     Copyright (c) 2014 IETF Trust and the persons identified as
     authors of the code.  All rights reserved.

     Redistribution and use in source and binary forms, with or
     without modification, is permitted pursuant to, and subject
     to the license terms contained in, the Simplified BSD License
     set forth in Section 4.c of the IETF Trust's Legal Provisions
     Relating to IETF Documents
     (http://trustee.ietf.org/license-info).

     This version of this YANG module is part of RFC XXXX; see
     the RFC itself for full legal notices.";

  // RFC Ed.: replace XXXX with actual RFC number and remove this
  // note.

  // RFC Ed.: update the date below with the date of RFC publication
  // and remove this note.

  revision 2014-05-06 {
    description
      "Initial revision.";
    reference
      "RFC XXXX: A YANG Data Model for SNMP Configuration";
  }

}
	    

<CODE ENDS>

4.3. Submodule 'ietf-snmp-common'

<CODE BEGINS> file "ietf-snmp-common.yang"

submodule ietf-snmp-common {

  belongs-to ietf-snmp {
    prefix snmp;
  }

  import ietf-yang-types {
    prefix yang;
  }

  organization
    "IETF NETMOD (NETCONF Data Modeling Language) Working Group";

  contact
    "WG Web:   <http://tools.ietf.org/wg/netmod/>
     WG List:  <mailto:netmod@ietf.org>

     WG Chair: Thomas Nadeau
               <mailto:tnadeau@lucidvision.com>

     WG Chair: Juergen Schoenwaelder
               <mailto:j.schoenwaelder@jacobs-university.de>

     Editor:   Martin Bjorklund
               <mailto:mbj@tail-f.com>

     Editor:   Juergen Schoenwaelder
               <mailto:j.schoenwaelder@jacobs-university.de>";

  description
    "This submodule contains a collection of common YANG definitions
     for configuring SNMP engines.

     Copyright (c) 2014 IETF Trust and the persons identified as
     authors of the code.  All rights reserved.

     Redistribution and use in source and binary forms, with or
     without modification, is permitted pursuant to, and subject
     to the license terms contained in, the Simplified BSD License
     set forth in Section 4.c of the IETF Trust's Legal Provisions
     Relating to IETF Documents
     (http://trustee.ietf.org/license-info).

     This version of this YANG module is part of RFC XXXX; see
     the RFC itself for full legal notices.";

  // RFC Ed.: replace XXXX with actual RFC number and remove this
  // note.

  // RFC Ed.: update the date below with the date of RFC publication
  // and remove this note.

  revision 2014-05-06 {
    description
      "Initial revision.";
    reference
      "RFC XXXX: A YANG Data Model for SNMP Configuration";
  }

  /* Collection of SNMP specific data types */

  typedef admin-string {
    type string {
      length "0..255";
    }
    description
      "Represents and SnmpAdminString as defined in RFC 3411.

      Note that the size of an SnmpAdminString is measured in
      octets, not characters.";
    reference "SNMP-FRAMEWORK-MIB.SnmpAdminString";
  }

  typedef identifier {
    type admin-string {
      length "1..32";
    }
    description
      "Identifiers are used to name items in the SNMP configuration
      data store.";
  }

  typedef context-name {
    type admin-string {
      length "0..32";
    }
    description
      "The context type represents an SNMP context name.";
    reference
      "RFC3411: An Architecture for Describing SNMP Management
                Frameworks";
  }

  typedef security-name {
    type admin-string {
      length "1..32";
    }
    description
      "The security-name type represents an SNMP security name.";
    reference
      "RFC3411: An Architecture for Describing SNMP Management
                Frameworks";
  }

  typedef security-model {
    type union {
      type enumeration {
        enum v1  { value 1; }
        enum v2c { value 2; }
        enum usm { value 3; }
        enum tsm { value 4; }
      }
      type int32 {
        range "1..2147483647";
      }
    }
    reference
      "RFC3411: An Architecture for Describing SNMP Management
                Frameworks";
  }

  typedef security-model-or-any {
    type union {
      type enumeration {
        enum any { value 0; }
      }
      type security-model;
    }
    reference
      "RFC3411: An Architecture for Describing SNMP Management
                Frameworks";
  }

  typedef security-level {
    type enumeration {
      enum no-auth-no-priv { value 1; }
      enum auth-no-priv    { value 2; }
      enum auth-priv       { value 3; }
    }
    reference
      "RFC3411: An Architecture for Describing SNMP Management
                Frameworks";
  }

  typedef engine-id {
    type yang:hex-string {
      pattern '([0-9a-fA-F]){2}(:([0-9a-fA-F]){2}){4,31}';
    }
    description
      "The Engine ID specified as a list of colon-specified hexa-
      decimal octets, e.g., '80:00:02:b8:04:61:62:63'.";
    reference
      "RFC3411: An Architecture for Describing SNMP Management
                Frameworks";
  }

  typedef wildcard-object-identifier {
    type string;
    description
      "The wildcard-object-identifier type represents an SNMP object
      identifier where subidentifiers can be given either as a label,
      in numeric form, or a wildcard, represented by a *.";
  }

  typedef tag-value {
    type string {
      length "0..255";
    }
    description
      "Represents and SnmpTagValue as defined in RFC 3413.

      Note that the size of an SnmpTagValue is measured in
      octets, not characters.";
    reference "SNMP-TARGET-MIB.SnmpTagValue";
  }

  container snmp {
    description
      "Top-level container for SNMP related configuration and
      status objects.";
  }

}
	    

<CODE ENDS>

4.4. Submodule 'ietf-snmp-engine'

<CODE BEGINS> file "ietf-snmp-engine.yang"

submodule ietf-snmp-engine {

  belongs-to ietf-snmp {
    prefix snmp;
  }

  import ietf-inet-types {
    prefix inet;
  }

  include ietf-snmp-common;

  organization
    "IETF NETMOD (NETCONF Data Modeling Language) Working Group";

  contact
    "WG Web:   <http://tools.ietf.org/wg/netmod/>
     WG List:  <mailto:netmod@ietf.org>

     WG Chair: Thomas Nadeau
               <mailto:tnadeau@lucidvision.com>

     WG Chair: Juergen Schoenwaelder
               <mailto:j.schoenwaelder@jacobs-university.de>

     Editor:   Martin Bjorklund
               <mailto:mbj@tail-f.com>

     Editor:   Juergen Schoenwaelder
               <mailto:j.schoenwaelder@jacobs-university.de>";

  description
    "This submodule contains a collection of YANG definitions
     for configuring SNMP engines.

     Copyright (c) 2014 IETF Trust and the persons identified as
     authors of the code.  All rights reserved.

     Redistribution and use in source and binary forms, with or
     without modification, is permitted pursuant to, and subject
     to the license terms contained in, the Simplified BSD License
     set forth in Section 4.c of the IETF Trust's Legal Provisions
     Relating to IETF Documents
     (http://trustee.ietf.org/license-info).

     This version of this YANG module is part of RFC XXXX; see
     the RFC itself for full legal notices.";

  // RFC Ed.: replace XXXX with actual RFC number and remove this
  // note.

  // RFC Ed.: update the date below with the date of RFC publication
  // and remove this note.

  revision 2014-05-06 {
    description
      "Initial revision.";
    reference
      "RFC XXXX: A YANG Data Model for SNMP Configuration";
  }

  augment /snmp:snmp {

    container engine {

      description
        "Configuration of the SNMP engine.";

      leaf enabled {
        type boolean;
        default "false";
        description
          "Enables the SNMP engine.";
      }

      list listen {
        key "name";
        description
          "Configuration of the transport endpoints on which the
           engine listens.";

        leaf name {
          type snmp:identifier;
          description
            "An arbitrary name for the list entry.";
        }

        choice transport {
          mandatory true;
          description
            "The transport protocol specific parameters for this
             endpoint.  Submodules providing configuration for
             additional transports are expected to augment this
             choice.";
          case udp {
            container udp {
              leaf ip {
                type inet:ip-address;
                mandatory true;
                description
                  "The IPv4 or IPv6 address on which the engine
                   listens.";
              }
              leaf port {
                type inet:port-number;
                description
                  "The UDP port on which the engine listens.

                   If the port is not configured, an engine that
                   acts as a Command Responder uses port 161, and
                   an engine that acts as a Notification Receiver
                   uses port 162.";
              }
            }
          }
        }
      }

      container version {
        description
          "SNMP version used by the engine";
        leaf v1 {
          type empty;
        }
        leaf v2c {
          type empty;
        }
        leaf v3 {
          type empty;
        }
      }

      leaf engine-id {
        type snmp:engine-id;
        description
          "The local SNMP engine's administratively-assigned unique
           identifier.

           If this leaf is not set, the device automatically
           calculates an engine id, as described in RFC 3411.  A
           server MAY initialize this leaf with the automatically
           created value.";
        reference "SNMP-FRAMEWORK-MIB.snmpEngineID";
      }

      leaf enable-authen-traps {
        type boolean;
        description
          "Indicates whether the SNMP entity is permitted to
           generate authenticationFailure traps.";
        reference "SNMPv2-MIB.snmpEnableAuthenTraps";
      }
    }
  }
}
	    

<CODE ENDS>

4.5. Submodule 'ietf-snmp-target'

<CODE BEGINS> file "ietf-snmp-target.yang"

submodule ietf-snmp-target {

  belongs-to ietf-snmp {
    prefix snmp;
  }

  import ietf-inet-types {
    prefix inet;
  }

  include ietf-snmp-common;

  organization
    "IETF NETMOD (NETCONF Data Modeling Language) Working Group";

  contact
    "WG Web:   <http://tools.ietf.org/wg/netmod/>
     WG List:  <mailto:netmod@ietf.org>

     WG Chair: Thomas Nadeau
               <mailto:tnadeau@lucidvision.com>

     WG Chair: Juergen Schoenwaelder
               <mailto:j.schoenwaelder@jacobs-university.de>

     Editor:   Martin Bjorklund
               <mailto:mbj@tail-f.com>

     Editor:   Juergen Schoenwaelder
               <mailto:j.schoenwaelder@jacobs-university.de>";

  description
    "This submodule contains a collection of YANG definitions
     for configuring SNMP targets.

     Copyright (c) 2014 IETF Trust and the persons identified as
     authors of the code.  All rights reserved.

     Redistribution and use in source and binary forms, with or
     without modification, is permitted pursuant to, and subject
     to the license terms contained in, the Simplified BSD License
     set forth in Section 4.c of the IETF Trust's Legal Provisions
     Relating to IETF Documents
     (http://trustee.ietf.org/license-info).

     This version of this YANG module is part of RFC XXXX; see
     the RFC itself for full legal notices.";

  // RFC Ed.: replace XXXX with actual RFC number and remove this
  // note.

  reference
    "RFC3413: Simple Network Management Protocol (SNMP)
              Applications";

  // RFC Ed.: update the date below with the date of RFC publication
  // and remove this note.

  revision 2014-05-06 {
    description
      "Initial revision.";
    reference
      "RFC XXXX: A YANG Data Model for SNMP Configuration";
  }

  augment /snmp:snmp {

    list target {
      key name;
      description
        "List of targets.";
      reference "SNMP-TARGET-MIB.snmpTargetAddrTable";

      leaf name {
        type snmp:identifier;
        description
          "Identifies the target.";
        reference "SNMP-TARGET-MIB.snmpTargetAddrName";
      }
      choice transport {
        mandatory true;
        description
          "Transport address of the target.

           The snmpTargetAddrTDomain and snmpTargetAddrTAddress
           objects are mapped to transport-specific YANG nodes.  Each
           transport is configured as a separate case in this
           choice. Submodules providing configuration for additional
           transports are expected to augment this choice.";
        reference "SNMP-TARGET-MIB.snmpTargetAddrTDomain
                   SNMP-TARGET-MIB.snmpTargetAddrTAddress";
        case udp {
          reference "SNMPv2-TM.snmpUDPDomain
                     TRANSPORT-ADDRESS-MIB.transportDomainUdpIpv4
                     TRANSPORT-ADDRESS-MIB.transportDomainUdpIpv4z
                     TRANSPORT-ADDRESS-MIB.transportDomainUdpIpv6
                     TRANSPORT-ADDRESS-MIB.transportDomainUdpIpv6z";
          container udp {
            leaf ip {
              type inet:ip-address;
              mandatory true;
              reference "SNMP-TARGET-MIB.snmpTargetAddrTAddress";
            }
            leaf port {
              type inet:port-number;
              default 162;
              description
                "UDP port number";
              reference "SNMP-TARGET-MIB.snmpTargetAddrTAddress";
            }
            leaf prefix-length {
              type uint8;
              description
                "The value of this leaf must match the value of
                 ../snmp:ip. If ../snmp:ip contains an ipv4 address,
                 this leaf must be less than or equal to 32.  If it
                 contains an ipv6 address, it must be less than or
                 equal to 128.

                 Note that the prefix-length is currently only used
                 by the Community-based Security Model to filter
                 incoming messages. Furthermore, the prefix-length
                 filtering does not cover all possible filters
                 supported by the corresponding MIB object.";
              reference "SNMP-COMMUNITY-MIB.snmpTargetAddrTMask";
            }
          }
        }
      }
      leaf-list tag {
        type snmp:tag-value;
        description
          "List of tag values used to select target address.";
        reference "SNMP-TARGET-MIB.snmpTargetAddrTagList";
      }
      leaf timeout {
        type uint32;
        units "0.01 seconds";
        default 1500;
        description
          "Needed only if this target can receive
           InformRequest-PDUs.";
        reference "SNMP-TARGET-MIB.snmpTargetAddrTimeout";
      }
      leaf retries {
        type uint8;
        default 3;
        description
          "Needed only if this target can receive
           InformRequest-PDUs.";
        reference "SNMP-TARGET-MIB.snmpTargetAddrRetryCount";
      }
      leaf target-params {
        type snmp:identifier;
        mandatory true;
        reference "SNMP-TARGET-MIB.snmpTargetAddrParams";
      }
    }

    list target-params {
      key name;
      description
        "List of target parameters.";
      reference "SNMP-TARGET-MIB.snmpTargetParamsTable";

      leaf name {
        type snmp:identifier;
      }
      choice params {
        description
          "This choice is augmented with case nodes containing
           security model specific configuration parameters.";
      }
    }
  }
}
	    

<CODE ENDS>

4.6. Submodule 'ietf-snmp-notification'

<CODE BEGINS> file "ietf-snmp-notification.yang"

submodule ietf-snmp-notification {

  belongs-to ietf-snmp {
    prefix snmp;
  }

  include ietf-snmp-common;
  include ietf-snmp-target;

  organization
    "IETF NETMOD (NETCONF Data Modeling Language) Working Group";

  contact
    "WG Web:   <http://tools.ietf.org/wg/netmod/>
     WG List:  <mailto:netmod@ietf.org>

     WG Chair: Thomas Nadeau
               <mailto:tnadeau@lucidvision.com>

     WG Chair: Juergen Schoenwaelder
               <mailto:j.schoenwaelder@jacobs-university.de>

     Editor:   Martin Bjorklund
               <mailto:mbj@tail-f.com>

     Editor:   Juergen Schoenwaelder
               <mailto:j.schoenwaelder@jacobs-university.de>";

  description
    "This submodule contains a collection of YANG definitions
     for configuring SNMP notifications.

     Copyright (c) 2014 IETF Trust and the persons identified as
     authors of the code.  All rights reserved.

     Redistribution and use in source and binary forms, with or
     without modification, is permitted pursuant to, and subject
     to the license terms contained in, the Simplified BSD License
     set forth in Section 4.c of the IETF Trust's Legal Provisions
     Relating to IETF Documents
     (http://trustee.ietf.org/license-info).

     This version of this YANG module is part of RFC XXXX; see
     the RFC itself for full legal notices.";

  // RFC Ed.: replace XXXX with actual RFC number and remove this
  // note.

  reference
    "RFC3413: Simple Network Management Protocol (SNMP)
              Applications";

  // RFC Ed.: update the date below with the date of RFC publication
  // and remove this note.

  revision 2014-05-06 {
    description
      "Initial revision.";
    reference
      "RFC XXXX: A YANG Data Model for SNMP Configuration";
  }

  feature notification-filter {
    description
      "A server implements this feature if it supports SNMP
      notification filtering.";
    reference
      "RFC3413: Simple Network Management Protocol (SNMP)
                Applications";
  }

  augment /snmp:snmp {

    list notify {
      key name;
      description
        "Targets that will receive notifications.

         Entries in this lists are mapped 1-1 to entries in
         snmpNotifyTable, except that if an entry in snmpNotifyTable
         has a snmpNotifyTag for which no snmpTargetAddrEntry exists,
         then the snmpNotifyTable entry is not mapped to an entry in
         this list.";
      reference "SNMP-NOTIFICATION-MIB.snmpNotifyTable";

      leaf name {
        type snmp:identifier;
        description
          "An arbitrary name for the list entry.";
        reference "SNMP-NOTIFICATION-MIB.snmpNotifyName";
      }
      leaf tag {
        type snmp:tag-value;
        mandatory true;
        description
          "Target tag, selects a set of notification targets.

           Implementations MAY restrict the values of this leaf
           to be one of the available values of /snmp/target/tag in
           a valid configuration.";
        reference "SNMP-NOTIFICATION-MIB.snmpNotifyTag";
      }
      leaf type {
        type enumeration {
          enum trap { value 1; }
          enum inform { value 2; }
        }
        default trap;
        description
          "Defines the notification type to be generated.";
        reference "SNMP-NOTIFICATION-MIB.snmpNotifyType";
      }
    }

    list notify-filter-profile {
      if-feature snmp:notification-filter;
      key name;

      description
        "Notification filter profiles.

         The leaf /snmp/target/notify-filter-profile is used
         to associate a filter profile with a target.

         If an entry in this list is referred to by one or more
         /snmp/target/notify-filter-profile, each such
         notify-filter-profile is represented by one
         snmpNotifyFilterProfileEntry.

         If an entry in this list is not referred to by any
         /snmp/target/notify-filter-profile, the entry is not mapped
         to snmpNotifyFilterProfileTable.";
      reference "SNMP-NOTIFICATION-MIB.snmpNotifyFilterProfileTable
                 SNMP-NOTIFICATION-MIB.snmpNotifyFilterTable";

      leaf name {
        type snmp:identifier;
        description
          "Name of the filter profile";
        reference
          "SNMP-NOTIFICATION-MIB.snmpNotifyFilterProfileName";
      }

      leaf-list include {
        type snmp:wildcard-object-identifier;
        description
          "A family of subtrees included in this filter.";
        reference "SNMP-NOTIFICATION-MIB.snmpNotifyFilterSubtree
                   SNMP-NOTIFICATION-MIB.snmpNotifyFilterMask
                   SNMP-NOTIFICATION-MIB.snmpNotifyFilterType";
      }

      leaf-list exclude {
        type snmp:wildcard-object-identifier;
        description
          "A family of subtrees excluded from this filter.";
        reference "SNMP-NOTIFICATION-MIB.snmpNotifyFilterSubtree
                   SNMP-NOTIFICATION-MIB.snmpNotifyFilterMask
                   SNMP-NOTIFICATION-MIB.snmpNotifyFilterType";
      }
    }

  }

  augment /snmp:snmp/snmp:target-params {
    reference "SNMP-NOTIFICATION-MIB.snmpNotifyFilterProfileTable";
    leaf notify-filter-profile {
      if-feature snmp:notification-filter;
      type leafref {
        path "/snmp/notify-filter-profile/name";
      }
      description
        "This leafref leaf is used to represent the sparse
         relationship between the /snmp/target-params list and the
         /snmp/notify-filter-profile list.";
      reference "SNMP-NOTIFICATION-MIB.snmpNotifyFilterProfileName";
    }
  }

}
	    

<CODE ENDS>

4.7. Submodule 'ietf-snmp-proxy'

<CODE BEGINS> file "ietf-snmp-proxy.yang"

submodule ietf-snmp-proxy {

  belongs-to ietf-snmp {
    prefix snmp;
  }

  include ietf-snmp-common;
  include ietf-snmp-target;

  organization
    "IETF NETMOD (NETCONF Data Modeling Language) Working Group";

  contact
    "WG Web:   <http://tools.ietf.org/wg/netmod/>
     WG List:  <mailto:netmod@ietf.org>

     WG Chair: Thomas Nadeau
               <mailto:tnadeau@lucidvision.com>

     WG Chair: Juergen Schoenwaelder
               <mailto:j.schoenwaelder@jacobs-university.de>

     Editor:   Martin Bjorklund
               <mailto:mbj@tail-f.com>

     Editor:   Juergen Schoenwaelder
               <mailto:j.schoenwaelder@jacobs-university.de>";

  description
    "This submodule contains a collection of YANG definitions
     for configuring SNMP proxies.

     Copyright (c) 2014 IETF Trust and the persons identified as
     authors of the code.  All rights reserved.

     Redistribution and use in source and binary forms, with or
     without modification, is permitted pursuant to, and subject
     to the license terms contained in, the Simplified BSD License
     set forth in Section 4.c of the IETF Trust's Legal Provisions
     Relating to IETF Documents
     (http://trustee.ietf.org/license-info).

     This version of this YANG module is part of RFC XXXX; see
     the RFC itself for full legal notices.";

  // RFC Ed.: replace XXXX with actual RFC number and remove this
  // note.

  reference
    "RFC3413: Simple Network Management Protocol (SNMP)
              Applications";

  // RFC Ed.: update the date below with the date of RFC publication
  // and remove this note.

  revision 2014-05-06 {
    description
      "Initial revision.";
    reference
      "RFC XXXX: A YANG Data Model for SNMP Configuration";
  }

  feature proxy {
    description
      "A server implements this feature if it can act as an
      SNMP Proxy";
    reference
      "RFC3413: Simple Network Management Protocol (SNMP)
                Applications";
  }

  augment /snmp:snmp {
    if-feature snmp:proxy;

    list proxy {
      key name;

      description
        "List of proxy parameters.";
      reference "SNMP-PROXY-MIB.snmpProxyTable";

      leaf name {
        type snmp:identifier;
        description
          "Identifies the proxy parameter entry.";
        reference "SNMP-PROXY-MIB.snmpProxyName";
      }
      leaf type {
        type enumeration {
          enum read { value 1; }
          enum write { value 2; }
          enum trap { value 3; }
          enum inform { value 4; }
        }
        mandatory true;
        reference "SNMP-PROXY-MIB.snmpProxyType";
      }
      leaf context-engine-id {
        type snmp:engine-id;
        mandatory true;
        reference "SNMP-PROXY-MIB.snmpProxyContextEngineID";
      }
      leaf context-name {
        type snmp:context-name;
        reference "SNMP-PROXY-MIB.snmpProxyContextName";
      }
      leaf target-params-in {
        type snmp:identifier;
        description
          "The name of a target parameters list entry.

           Implementations MAY restrict the values of this
           leaf to be one of the available values of
           /snmp/target-params/name in a valid configuration.";
        reference "SNMP-PROXY-MIB.snmpProxyTargetParamsIn";
      }
      leaf single-target-out {
        when "../type = 'read' or ../type = 'write'";
        type snmp:identifier;
        description
          "Implementations MAY restrict the values of this leaf
           to be one of the available values of /snmp/target/name in
           a valid configuration.";
        reference "SNMP-PROXY-MIB.snmpProxySingleTargetOut";
      }
      leaf multiple-target-out {
        when "../type = 'trap' or ../type = 'inform'";
        type snmp:tag-value;
        description
          "Implementations MAY restrict the values of this leaf
           to be one of the available values of /snmp/target/tag in
           a valid configuration.";
        reference "SNMP-PROXY-MIB.snmpProxyMultipleTargetOut";
      }
    }
  }
}
	    

<CODE ENDS>

4.8. Submodule 'ietf-snmp-community'

<CODE BEGINS> file "ietf-snmp-community.yang"

submodule ietf-snmp-community {

  belongs-to ietf-snmp {
    prefix snmp;
  }

  import ietf-netconf-acm {
    prefix nacm;
  }

  include ietf-snmp-common;
  include ietf-snmp-target;
  include ietf-snmp-proxy;

  organization
    "IETF NETMOD (NETCONF Data Modeling Language) Working Group";

  contact
    "WG Web:   <http://tools.ietf.org/wg/netmod/>
     WG List:  <mailto:netmod@ietf.org>

     WG Chair: Thomas Nadeau
               <mailto:tnadeau@lucidvision.com>

     WG Chair: Juergen Schoenwaelder
               <mailto:j.schoenwaelder@jacobs-university.de>

     Editor:   Martin Bjorklund
               <mailto:mbj@tail-f.com>

     Editor:   Juergen Schoenwaelder
               <mailto:j.schoenwaelder@jacobs-university.de>";

  description
    "This submodule contains a collection of YANG definitions
     for configuring community-based SNMP.

     Copyright (c) 2014 IETF Trust and the persons identified as
     authors of the code.  All rights reserved.

     Redistribution and use in source and binary forms, with or
     without modification, is permitted pursuant to, and subject
     to the license terms contained in, the Simplified BSD License
     set forth in Section 4.c of the IETF Trust's Legal Provisions
     Relating to IETF Documents
     (http://trustee.ietf.org/license-info).

     This version of this YANG module is part of RFC XXXX; see
     the RFC itself for full legal notices.";

  // RFC Ed.: replace XXXX with actual RFC number and remove this
  // note.

  reference
    "RFC3584: Coexistence between Version 1, Version 2, and Version 3
              of the Internet-standard Network Management Framework";

  // RFC Ed.: update the date below with the date of RFC publication
  // and remove this note.

  revision 2014-05-06 {
    description
      "Initial revision.";
    reference
      "RFC XXXX: A YANG Data Model for SNMP Configuration";
  }

  augment /snmp:snmp {

    list community {
      key index;

      description
        "List of communities";
      reference "SNMP-COMMUNITY-MIB.snmpCommunityTable";

      leaf index {
        type snmp:identifier;
        description
          "Index into the community list.";
        reference "SNMP-COMMUNITY-MIB.snmpCommunityIndex";
      }
      choice name {
        nacm:default-deny-all;
        description
          "The community name, either specified as a string
           or as a binary.  The binary name is used when the
           community name contains characters that are not legal
           in a string.

           If not set, the value of 'security-name' is operationally
           used as the snmpCommunityName.";
        reference "SNMP-COMMUNITY-MIB.snmpCommunityName";
        leaf text-name {
          type string;
          description
            "A community name that can be represented as a
             YANG string.";
        }
        leaf binary-name {
          type binary;
          description
            "A community name represented as a binary value.";
        }
      }
      leaf security-name {
        type snmp:security-name;
        mandatory true;
        nacm:default-deny-all;
        description
          "The snmpCommunitySecurityName of this entry.";
        reference "SNMP-COMMUNITY-MIB.snmpCommunitySecurityName";
      }
      leaf engine-id {
        if-feature snmp:proxy;
        type snmp:engine-id;
        description
          "If not set, the value of the local SNMP engine is
           operationally used by the device.";
        reference "SNMP-COMMUNITY-MIB.snmpCommunityContextEngineID";
      }
      leaf context {
        type snmp:context-name;
        default "";
        description
          "The context in which management information is accessed
           when using the community string specified by this entry.";
        reference "SNMP-COMMUNITY-MIB.snmpCommunityContextName";
      }
      leaf target-tag {
        type snmp:tag-value;
        description
          "Used to limit access for this community to the specified
           targets.

           Implementations MAY restrict the values of this leaf
           to be one of the available values of /snmp/target/tag in
           a valid configuration.";
        reference "SNMP-COMMUNITY-MIB.snmpCommunityTransportTag";
      }
    }
  }

  grouping v1-target-params {
    container v1 {
      description
        "SNMPv1 parameters type.
         Represents snmpTargetParamsMPModel '0',
         snmpTargetParamsSecurityModel '1', and
         snmpTargetParamsSecurityLevel 'noAuthNoPriv'.";
      leaf security-name {
        type snmp:security-name;
        mandatory true;
        description
          "Implementations MAY restrict the values of this leaf
           to be one of the available values of
           /snmp/community/security-name in a valid configuration.";
        reference "SNMP-TARGET-MIB.snmpTargetParamsSecurityName";
      }
    }
  }

  grouping v2c-target-params {
    container v2c {
      description
        "SNMPv2 community parameters type.
         Represents snmpTargetParamsMPModel '1',
         snmpTargetParamsSecurityModel '2', and
         snmpTargetParamsSecurityLevel 'noAuthNoPriv'.";
      leaf security-name {
        type snmp:security-name;
        mandatory true;
        description
          "Implementations MAY restrict the values of this leaf
           to be one of the available values of
           /snmp/community/security-name in a valid configuration.";
        reference "SNMP-TARGET-MIB.snmpTargetParamsSecurityName";
      }
    }
  }

  augment /snmp:snmp/snmp:target-params/snmp:params {
    case v1 {
      uses v1-target-params;
    }
    case v2c {
      uses v2c-target-params;
    }
  }

  augment /snmp:snmp/snmp:target {
    when "snmp:v1 or snmp:v2c";
    leaf mms {
      type union {
        type enumeration {
          enum "unknown" { value 0; }
        }
        type int32 {
          range "484..max";
        }
      }
      default "484";
      description
        "The maximum message size.";
      reference
        "SNMP-COMMUNITY-MIB.snmpTargetAddrMMS";
    }
  }

}
	    

<CODE ENDS>

4.9. Submodule 'ietf-snmp-vacm'

<CODE BEGINS> file "ietf-snmp-vacm.yang"

submodule ietf-snmp-vacm {

  belongs-to ietf-snmp {
    prefix snmp;
  }

  include ietf-snmp-common;

  organization
    "IETF NETMOD (NETCONF Data Modeling Language) Working Group";

  contact
    "WG Web:   <http://tools.ietf.org/wg/netmod/>
     WG List:  <mailto:netmod@ietf.org>

     WG Chair: Thomas Nadeau
               <mailto:tnadeau@lucidvision.com>

     WG Chair: Juergen Schoenwaelder
               <mailto:j.schoenwaelder@jacobs-university.de>

     Editor:   Martin Bjorklund
               <mailto:mbj@tail-f.com>

     Editor:   Juergen Schoenwaelder
               <mailto:j.schoenwaelder@jacobs-university.de>";

  description
    "This submodule contains a collection of YANG definitions
     for configuring the View-based Access Control Model (VACM)
     of SNMP.

     Copyright (c) 2014 IETF Trust and the persons identified as
     authors of the code.  All rights reserved.

     Redistribution and use in source and binary forms, with or
     without modification, is permitted pursuant to, and subject
     to the license terms contained in, the Simplified BSD License
     set forth in Section 4.c of the IETF Trust's Legal Provisions
     Relating to IETF Documents
     (http://trustee.ietf.org/license-info).

     This version of this YANG module is part of RFC XXXX; see
     the RFC itself for full legal notices.";

  // RFC Ed.: replace XXXX with actual RFC number and remove this
  // note.

  reference
    "RFC3415: View-based Access Control Model (VACM) for the
              Simple Network Management Protocol (SNMP)";

  // RFC Ed.: update the date below with the date of RFC publication
  // and remove this note.

  revision 2014-05-06 {
    description
      "Initial revision.";
    reference
      "RFC XXXX: A YANG Data Model for SNMP Configuration";
  }

  typedef view-name {
    type snmp:identifier;
    description
      "The view-name type represents an SNMP VACM view name.";
  }

  typedef group-name {
    type snmp:identifier;
    description
      "The group-name type represents an SNMP VACM group name.";
  }

  augment /snmp:snmp {

    container vacm {
      description
        "Configuration of the View-based Access Control Model";

      list group {
        key name;
        description
          "VACM Groups.

           This data model has a different structure than the MIB.
           Groups are explicitly defined in this list, and group
           members are defined in the 'member' list (mapped to
           vacmSecurityToGroupTable), and access for the group is
           defined in the 'access' list (mapped to
           vacmAccessTable).";
        reference "SNMP-VIEW-BASED-ACM-MIB.vacmSecurityToGroupTable
                   SNMP-VIEW-BASED-ACM-MIB.vacmAccessTable";

        leaf name {
          type group-name;
          description
            "The name of this VACM group.";
          reference "SNMP-VIEW-BASED-ACM-MIB.vacmGroupName";
        }

        list member {
          key "security-name";
          description
            "A member of this VACM group.

             A certain combination of security-name and
             security-model MUST NOT be present in more than
             one group.";
          reference
            "SNMP-VIEW-BASED-ACM-MIB.vacmSecurityToGroupTable";

          leaf security-name {
            type snmp:security-name;
            description
              "The securityName of a group member.";
            reference "SNMP-VIEW-BASED-ACM-MIB.vacmSecurityName";
          }

          leaf-list security-model {
            type snmp:security-model;
            min-elements 1;
            description
              "The security models under which this security-name
               is a member of this group.";
            reference "SNMP-VIEW-BASED-ACM-MIB.vacmSecurityModel";
          }
        }

        list access {
          key "context security-model security-level";
          description
            "Definition of access right for groups";
          reference "SNMP-VIEW-BASED-ACM-MIB.vacmAccessTable";

          leaf context {
            type snmp:context-name;
            description
              "The context (prefix) under which the access rights
               apply.";
            reference
              "SNMP-VIEW-BASED-ACM-MIB.vacmAccessContextPrefix";
          }

          leaf context-match {
            type enumeration {
              enum exact { value 1; }
              enum prefix { value 2; }
            }
            default exact;
            reference
              "SNMP-VIEW-BASED-ACM-MIB.vacmAccessContextMatch";
          }

          leaf security-model {
            type snmp:security-model-or-any;
            description
              "The security model under which the access rights
              apply.";
            reference
              "SNMP-VIEW-BASED-ACM-MIB.vacmAccessSecurityModel";
          }

          leaf security-level {
            type snmp:security-level;
            description
              "The minimum security level under which the access
               rights apply.";
            reference
              "SNMP-VIEW-BASED-ACM-MIB.vacmAccessSecurityLevel";
          }

          leaf read-view {
            type view-name;
            description
              "The name of the MIB view of the SNMP context
               authorizing read access. If this leaf does not
               exist in a configuration, it maps to a zero-length
               vacmAccessReadViewName.

               Implementations MAY restrict the values of this
               leaf to be one of the available values of
               /snmp/vacm/view/name in a valid configuration.";
            reference
              "SNMP-VIEW-BASED-ACM-MIB.vacmAccessReadViewName";
          }

          leaf write-view {
            type view-name;
            description
              "The name of the MIB view of the SNMP context
               authorizing write access. If this leaf does not
               exist in a configuration, it maps to a zero-length
               vacmAccessWriteViewName.

               Implementations MAY restrict the values of this
               leaf to be one of the available values of
               /snmp/vacm/view/name in a valid configuration.";
            reference
              "SNMP-VIEW-BASED-ACM-MIB.vacmAccessWriteViewName";
          }

          leaf notify-view {
            type view-name;
            description
              "The name of the MIB view of the SNMP context
               authorizing notify access. If this leaf does not
               exist in a configuration, it maps to a zero-length
               vacmAccessNotifyViewName.

               Implementations MAY restrict the values of this
               leaf to be one of the available values of
               /snmp/vacm/view/name in a valid configuration.";
            reference
              "SNMP-VIEW-BASED-ACM-MIB.vacmAccessNotifyViewName";
          }
        }
      }

      list view {
        key name;
        description
          "Definition of MIB views.";
        reference
          "SNMP-VIEW-BASED-ACM-MIB.vacmViewTreeFamilyTable";

        leaf name {
          type view-name;
          description
            "The name of this VACM MIB view.";
          reference
            "SNMP-VIEW-BASED-ACM-MIB.vacmViewTreeFamilyName";
        }

        leaf-list include {
          type snmp:wildcard-object-identifier;
          description
            "A family of subtrees included in this MIB view.";
          reference
              "SNMP-VIEW-BASED-ACM-MIB.vacmViewTreeFamilySubtree
               SNMP-VIEW-BASED-ACM-MIB.vacmViewTreeFamilyMask
               SNMP-VIEW-BASED-ACM-MIB.vacmViewTreeFamilyType";
        }

        leaf-list exclude {
          type snmp:wildcard-object-identifier;
          description
            "A family of subtrees excluded from this MIB view.";
          reference
              "SNMP-VIEW-BASED-ACM-MIB.vacmViewTreeFamilySubtree
               SNMP-VIEW-BASED-ACM-MIB.vacmViewTreeFamilyMask
               SNMP-VIEW-BASED-ACM-MIB.vacmViewTreeFamilyType";
        }
      }
    }
  }
}
	    

<CODE ENDS>

4.10. Submodule 'ietf-snmp-usm'

This YANG submodule imports YANG extensions from [RFC6536].

<CODE BEGINS> file "ietf-snmp-usm.yang"

submodule ietf-snmp-usm {

  belongs-to ietf-snmp {
    prefix snmp;
  }

  import ietf-yang-types {
    prefix yang;
  }
  import ietf-netconf-acm {
    prefix nacm;
  }

  include ietf-snmp-common;
  include ietf-snmp-target;
  include ietf-snmp-proxy;

  organization
    "IETF NETMOD (NETCONF Data Modeling Language) Working Group";

  contact
    "WG Web:   <http://tools.ietf.org/wg/netmod/>
     WG List:  <mailto:netmod@ietf.org>

     WG Chair: Thomas Nadeau
               <mailto:tnadeau@lucidvision.com>

     WG Chair: Juergen Schoenwaelder
               <mailto:j.schoenwaelder@jacobs-university.de>

     Editor:   Martin Bjorklund
               <mailto:mbj@tail-f.com>

     Editor:   Juergen Schoenwaelder
               <mailto:j.schoenwaelder@jacobs-university.de>";

  description
    "This submodule contains a collection of YANG definitions for
     configuring the User-based Security Model (USM) of SNMP.

     Copyright (c) 2014 IETF Trust and the persons identified as
     authors of the code.  All rights reserved.

     Redistribution and use in source and binary forms, with or
     without modification, is permitted pursuant to, and subject
     to the license terms contained in, the Simplified BSD License
     set forth in Section 4.c of the IETF Trust's Legal Provisions
     Relating to IETF Documents
     (http://trustee.ietf.org/license-info).

     This version of this YANG module is part of RFC XXXX; see
     the RFC itself for full legal notices.";

  // RFC Ed.: replace XXXX with actual RFC number and remove this
  // note.

  reference
    "RFC3414: User-based Security Model (USM) for version 3 of the
              Simple Network Management Protocol (SNMPv3).";

  // RFC Ed.: update the date below with the date of RFC publication
  // and remove this note.

  revision 2014-05-06 {
    description
      "Initial revision.";
    reference
      "RFC XXXX: A YANG Data Model for SNMP Configuration";
  }

  grouping key {
    leaf key {
      type yang:hex-string;
      mandatory true;
      nacm:default-deny-all;
      description
        "Localized key specified as a list of colon-specified
         hexa-decimal octets";
    }
  }

  grouping user-list {
    list user {
      key "name";

      reference "SNMP-USER-BASED-SM-MIB.usmUserTable";

      leaf name {
        type snmp:identifier;
        reference "SNMP-USER-BASED-SM-MIB.usmUserName";
      }
      container auth {
        presence "enables authentication";
        description
          "Enables authentication of the user";
        choice protocol {
          mandatory true;
          reference "SNMP-USER-BASED-SM-MIB.usmUserAuthProtocol";
          container md5 {
            uses key;
            reference
              "SNMP-USER-BASED-SM-MIB.usmHMACMD5AuthProtocol";
          }
          container sha {
            uses key;
            reference
              "SNMP-USER-BASED-SM-MIB.usmHMACSHAAuthProtocol";
          }
        }
      }
      container priv {
        must "../auth" {
          error-message
            "when privacy (confidentiality) is used, "
          + "authentication must also be used";
        }
        presence "enables encryption";
        description
          "Enables encryption of SNMP messages.";

        choice protocol {
          mandatory true;
          reference "SNMP-USER-BASED-SM-MIB.usmUserPrivProtocol";
          container des {
            uses key;
            reference "SNMP-USER-BASED-SM-MIB.usmDESPrivProtocol";
          }
          container aes {
            uses key;
            reference "SNMP-USM-AES-MIB.usmAesCfb128Protocol";
          }
        }
      }
    }
  }

  augment /snmp:snmp {

    container usm {
      description
        "Configuration of the User-based Security Model";
      container local {
        uses user-list;
      }

      list remote {
        key "engine-id";

        leaf engine-id {
          type snmp:engine-id;
          reference "SNMP-USER-BASED-SM-MIB.usmUserEngineID";
        }

        uses user-list;
      }
    }
  }

  grouping usm-target-params {
    container usm {
      description
        "User based SNMPv3 parameters type.

         Represents snmpTargetParamsMPModel '3' and
         snmpTargetParamsSecurityModel '3'";
      leaf user-name {
        type snmp:security-name;
        mandatory true;
        reference
          "SNMP-TARGET-MIB.snmpTargetParamsSecurityName";
      }
      leaf security-level {
        type snmp:security-level;
        mandatory true;
        reference
          "SNMP-TARGET-MIB.snmpTargetParamsSecurityLevel";
      }
    }
  }

  augment /snmp:snmp/snmp:target-params/snmp:params {
    case usm {
      uses usm-target-params;
    }
  }

}
	    

<CODE ENDS>

4.11. Submodule 'ietf-snmp-tsm'

<CODE BEGINS> file "ietf-snmp-tsm.yang"

submodule ietf-snmp-tsm {

  belongs-to ietf-snmp {
    prefix snmp;
  }

  include ietf-snmp-common;
  include ietf-snmp-target;
  include ietf-snmp-proxy;

  organization
    "IETF NETMOD (NETCONF Data Modeling Language) Working Group";

  contact
    "WG Web:   <http://tools.ietf.org/wg/netmod/>
     WG List:  <mailto:netmod@ietf.org>

     WG Chair: Thomas Nadeau
               <mailto:tnadeau@lucidvision.com>

     WG Chair: Juergen Schoenwaelder
               <mailto:j.schoenwaelder@jacobs-university.de>

     Editor:   Martin Bjorklund
               <mailto:mbj@tail-f.com>

     Editor:   Juergen Schoenwaelder
               <mailto:j.schoenwaelder@jacobs-university.de>";

  description
    "This submodule contains a collection of YANG definitions for
     configuring the Transport Security Model (TSM) of SNMP.

     Copyright (c) 2014 IETF Trust and the persons identified as
     authors of the code.  All rights reserved.

     Redistribution and use in source and binary forms, with or
     without modification, is permitted pursuant to, and subject
     to the license terms contained in, the Simplified BSD License
     set forth in Section 4.c of the IETF Trust's Legal Provisions
     Relating to IETF Documents
     (http://trustee.ietf.org/license-info).

     This version of this YANG module is part of RFC XXXX; see
     the RFC itself for full legal notices.";

  // RFC Ed.: replace XXXX with actual RFC number and remove this
  // note.

  reference
    "RFC5591: Transport Security Model for the
              Simple Network Management Protocol (SNMP)";

  // RFC Ed.: update the date below with the date of RFC publication
  // and remove this note.

  revision 2014-05-06 {
    description
      "Initial revision.";
    reference
      "RFC XXXX: A YANG Data Model for SNMP Configuration";
  }

  feature tsm {
    description
      "A server implements this feature if it supports the
      Transport Security Model for SNMP.";
    reference
      "RFC5591: Transport Security Model for the
                Simple Network Management Protocol (SNMP)";
  }

  augment /snmp:snmp {
    if-feature tsm;
    container tsm {
      description
        "Configuration of the Transport-based Security Model";

      leaf use-prefix {
        type boolean;
        default false;
        reference
          "SNMP-TSM-MIB.snmpTsmConfigurationUsePrefix";
      }
    }
  }

  grouping tsm-target-params {
    container tsm {
      description
        "Transport based security SNMPv3 parameters type.

         Represents snmpTargetParamsMPModel '3' and
         snmpTargetParamsSecurityModel '4'";
      leaf security-name {
        type snmp:security-name;
        mandatory true;
        reference
          "SNMP-TARGET-MIB.snmpTargetParamsSecurityName";
      }
      leaf security-level {
        type snmp:security-level;
        mandatory true;
        reference
          "SNMP-TARGET-MIB.snmpTargetParamsSecurityLevel";
      }
    }
  }

  augment /snmp:snmp/snmp:target-params/snmp:params {
    if-feature tsm;
    case tsm {
      uses tsm-target-params;
    }
  }

}
	    

<CODE ENDS>

4.12. Submodule 'ietf-snmp-tls'

<CODE BEGINS> file "ietf-snmp-tls.yang"

submodule ietf-snmp-tls {

  belongs-to ietf-snmp {
    prefix snmp;
  }

  import ietf-inet-types {
    prefix inet;
  }
  import ietf-x509-cert-to-name {
    prefix x509c2n;
  }

  include ietf-snmp-common;
  include ietf-snmp-engine;
  include ietf-snmp-target;

  organization
    "IETF NETMOD (NETCONF Data Modeling Language) Working Group";

  contact
    "WG Web:   <http://tools.ietf.org/wg/netmod/>
     WG List:  <mailto:netmod@ietf.org>

     WG Chair: Thomas Nadeau
               <mailto:tnadeau@lucidvision.com>

     WG Chair: Juergen Schoenwaelder
               <mailto:j.schoenwaelder@jacobs-university.de>

     Editor:   Martin Bjorklund
               <mailto:mbj@tail-f.com>

     Editor:   Juergen Schoenwaelder
               <mailto:j.schoenwaelder@jacobs-university.de>";

  description
    "This submodule contains a collection of YANG definitions for
     configuring the Transport Layer Security Transport Model (TLSTM)
     of SNMP.

     Copyright (c) 2014 IETF Trust and the persons identified as
     authors of the code.  All rights reserved.

     Redistribution and use in source and binary forms, with or
     without modification, is permitted pursuant to, and subject
     to the license terms contained in, the Simplified BSD License
     set forth in Section 4.c of the IETF Trust's Legal Provisions
     Relating to IETF Documents
     (http://trustee.ietf.org/license-info).

     This version of this YANG module is part of RFC XXXX; see
     the RFC itself for full legal notices.";

  // RFC Ed.: replace XXXX with actual RFC number and remove this
  // note.

  reference
    "RFC6353: Transport Layer Security (TLS) Transport Model for
              the Simple Network Management Protocol (SNMP)";

  // RFC Ed.: update the date below with the date of RFC publication
  // and remove this note.

  revision 2014-05-06 {
    description
      "Initial revision.";
    reference
      "RFC XXXX: A YANG Data Model for SNMP Configuration";
  }

  feature tlstm {
    description
      "A server implements this feature if it supports the
      Transport Layer Security Transport Model for SNMP.";
    reference
      "RFC6353: Transport Layer Security (TLS) Transport Model for
                the Simple Network Management Protocol (SNMP)";
  }

  augment /snmp:snmp/snmp:engine/snmp:listen/snmp:transport {
    if-feature tlstm;
    case tls {
      container tls {
        description
          "A list of IPv4 and IPv6 addresses and ports to which the
           engine listens for SNMP messages over TLS.";

        leaf ip {
          type inet:ip-address;
          mandatory true;
          description
            "The IPv4 or IPv6 address on which the engine listens
             for SNMP messages over TLS.";
        }
        leaf port {
          type inet:port-number;
          description
            "The TCP port on which the engine listens for SNMP
             messages over TLS.

             If the port is not configured, an engine that
             acts as a Command Responder uses port 10161, and
             an engine that acts as a Notification Receiver
             uses port 10162.";
        }
      }
    }
    case dtls {
      container dtls {
        description
          "A list of IPv4 and IPv6 addresses and ports to which the
           engine listens for SNMP messages over DTLS.";

        leaf ip {
          type inet:ip-address;
          mandatory true;
          description
            "The IPv4 or IPv6 address on which the engine listens
             for SNMP messages over DTLS.";
        }
        leaf port {
          type inet:port-number;
          description
            "The UDP port on which the engine listens for SNMP
             messages over DTLS.

             If the port is not configured, an engine that
             acts as a Command Responder uses port 10161, and
             an engine that acts as a Notification Receiver
             uses port 10162.";
        }
      }
    }
  }

  augment /snmp:snmp {
    if-feature tlstm;
    container tlstm {
      uses x509c2n:cert-to-name {
        description
          "Defines how certificates are mapped to names.  The
           resulting name is used as a security name.";
        refine cert-to-name/map-type {
          description
            "Mappings that use the snmpTlstmCertToTSNData column
             need to augment the 'cert-to-name' list
             with additional configuration objects corresponding
             to the snmpTlstmCertToTSNData value.  Such objects
             should use the 'when' statement to make them
             conditional based on the 'map-type'.";
        }
      }
    }
  }

  grouping tls-transport {
    leaf ip {
      type inet:host;
      mandatory true;
      reference "SNMP-TARGET-MIB.snmpTargetAddrTAddress
                 SNMP-TLS-TM-MIB.SnmpTLSAddress";
    }
    leaf port {
      type inet:port-number;
      default 10161;
      reference "SNMP-TARGET-MIB.snmpTargetAddrTAddress
                 SNMP-TLS-TM-MIB.SnmpTLSAddress";
    }
    leaf client-fingerprint {
      type x509c2n:tls-fingerprint;
      reference "SNMP-TLS-TM-MIB.snmpTlstmParamsClientFingerprint";
    }
    leaf server-fingerprint {
      type x509c2n:tls-fingerprint;
      reference "SNMP-TLS-TM-MIB.snmpTlstmAddrServerFingerprint";
    }
    leaf server-identity {
      type snmp:admin-string;
      reference "SNMP-TLS-TM-MIB.snmpTlstmAddrServerIdentity";
    }
  }

  augment /snmp:snmp/snmp:target/snmp:transport {
    if-feature tlstm;
    case tls {
      reference "SNMP-TLS-TM-MIB.snmpTLSTCPDomain";
      container tls {
        uses tls-transport;
      }
    }
  }

  augment /snmp:snmp/snmp:target/snmp:transport {
    if-feature tlstm;
    case dtls {
      reference "SNMP-TLS-TM-MIB.snmpDTLSUDPDomain";
      container dtls {
        uses tls-transport;
      }
    }
  }
}
	    

<CODE ENDS>

4.13. Submodule 'ietf-snmp-ssh'

<CODE BEGINS> file "ietf-snmp-ssh.yang"

submodule ietf-snmp-ssh {

  belongs-to ietf-snmp {
    prefix snmp;
  }

  import ietf-inet-types {
    prefix inet;
  }

  include ietf-snmp-common;
  include ietf-snmp-engine;
  include ietf-snmp-target;

  organization
    "IETF NETMOD (NETCONF Data Modeling Language) Working Group";

  contact
    "WG Web:   <http://tools.ietf.org/wg/netmod/>
     WG List:  <mailto:netmod@ietf.org>

     WG Chair: Thomas Nadeau
               <mailto:tnadeau@lucidvision.com>

     WG Chair: Juergen Schoenwaelder
               <mailto:j.schoenwaelder@jacobs-university.de>

     Editor:   Martin Bjorklund
               <mailto:mbj@tail-f.com>

     Editor:   Juergen Schoenwaelder
               <mailto:j.schoenwaelder@jacobs-university.de>";

  description
    "This submodule contains a collection of YANG definitions for
     configuring the Secure Shell Transport Model (SSHTM)
     of SNMP.

     Copyright (c) 2014 IETF Trust and the persons identified as
     authors of the code.  All rights reserved.

     Redistribution and use in source and binary forms, with or
     without modification, is permitted pursuant to, and subject
     to the license terms contained in, the Simplified BSD License
     set forth in Section 4.c of the IETF Trust's Legal Provisions
     Relating to IETF Documents
     (http://trustee.ietf.org/license-info).

     This version of this YANG module is part of RFC XXXX; see
     the RFC itself for full legal notices.";

  // RFC Ed.: replace XXXX with actual RFC number and remove this
  // note.

  reference
    "RFC5592: Secure Shell Transport Model for the
              Simple Network Management Protocol (SNMP)";

  // RFC Ed.: update the date below with the date of RFC publication
  // and remove this note.

  revision 2014-05-06 {
    description
      "Initial revision.";
    reference
      "RFC XXXX: A YANG Data Model for SNMP Configuration";
  }

  feature sshtm {
    description
      "A server implements this feature if it supports the
      Secure Shell Transport Model for SNMP.";
    reference
      "RFC5592: Secure Shell Transport Model for the
                Simple Network Management Protocol (SNMP)";
  }

  augment /snmp:snmp/snmp:engine/snmp:listen/snmp:transport {
    if-feature sshtm;
    case ssh {
      container ssh {
        description
          "The IPv4 or IPv6 address and port to which the
           engine listens for SNMP messages over SSH.";

        leaf ip {
          type inet:ip-address;
          mandatory true;
          description
            "The IPv4 or IPv6 address on which the engine listens
             for SNMP messages over SSH.";
        }
        leaf port {
          type inet:port-number;
          description
            "The TCP port on which the engine listens for SNMP
             messages over SSH.

             If the port is not configured, an engine that
             acts as a Command Responder uses port 5161, and
             an engine that acts as a Notification Receiver
             uses port 5162.";
        }
      }
    }
  }

  augment /snmp:snmp/snmp:target/snmp:transport {
    if-feature sshtm;
    case ssh {
      reference "SNMP-SSH-TM-MIB.snmpSSHDomain";
      container ssh {
        leaf ip {
          type inet:host;
          mandatory true;
          reference "SNMP-TARGET-MIB.snmpTargetAddrTAddress
                     SNMP-SSH-TM-MIB.SnmpSSHAddress";
        }
        leaf port {
          type inet:port-number;
          default 5161;
          reference "SNMP-TARGET-MIB.snmpTargetAddrTAddress
                     SNMP-SSH-TM-MIB.SnmpSSHAddress";
        }
        leaf username {
          type string;
          reference "SNMP-TARGET-MIB.snmpTargetAddrTAddress
                     SNMP-SSH-TM-MIB.SnmpSSHAddress";
        }
      }
    }
  }
}

	    

<CODE ENDS>

5. IANA Considerations

This document registers two URIs in the IETF XML registry [RFC3688]. Following the format in RFC 3688, the following registrations are requested to be made.

     URI: urn:ietf:params:xml:ns:yang:ietf-snmp
     Registrant Contact: The NETMOD WG of the IETF.
     XML: N/A, the requested URI is an XML namespace.

     URI: urn:ietf:params:xml:ns:yang:ietf-x509-cert-to-name
     Registrant Contact: The NETMOD WG of the IETF.
     XML: N/A, the requested URI is an XML namespace.
	    

This document registers the following YANG modules in the YANG Module Names registry [RFC6020].

     name:         ietf-snmp
     namespace:    urn:ietf:params:xml:ns:yang:ietf-snmp
     prefix:       snmp
     reference:    RFC XXXX

     name:         ietf-x509-cert-to-name
     namespace:    urn:ietf:params:xml:ns:yang:ietf-x509-cert-to-name
     prefix:       x509c2n
     reference:    RFC XXXX
	    

The document registers the following YANG submodules in the YANG Module Names registry [RFC6020].

     name:         ietf-snmp-common
     parent:       ietf-snmp
     reference:    RFC XXXX

     name:         ietf-snmp-engine
     parent:       ietf-snmp
     reference:    RFC XXXX

     name:         ietf-snmp-community
     parent:       ietf-snmp
     reference:    RFC XXXX

     name:         ietf-snmp-notification
     parent:       ietf-snmp
     reference:    RFC XXXX

     name:         ietf-snmp-target
     parent:       ietf-snmp
     reference:    RFC XXXX

     name:         ietf-snmp-vacm
     parent:       ietf-snmp
     reference:    RFC XXXX

     name:         ietf-snmp-usm
     parent:       ietf-snmp
     reference:    RFC XXXX

     name:         ietf-snmp-tsm
     parent:       ietf-snmp
     reference:    RFC XXXX

     name:         ietf-snmp-tls
     parent:       ietf-snmp
     reference:    RFC XXXX

     name:         ietf-snmp-ssh
     parent:       ietf-snmp
     reference:    RFC XXXX
	    

6. Security Considerations

The YANG module and submodules defined in this memo are designed to be accessed via the NETCONF protocol [RFC6241]. The lowest NETCONF layer is the secure transport layer and the mandatory-to-implement secure transport is SSH [RFC6242].

There are a number of data nodes defined in the YANG module and submodules which are writable/creatable/deletable (i.e., config true, which is the default). These data nodes may be considered sensitive or vulnerable in some network environments. Write operations (e.g., edit-config) to these data nodes without proper protection can have a negative effect on network operations. These are the subtrees and data nodes and their sensitivity/vulnerability:

Some of the readable data nodes in the YANG module and submodules may be considered sensitive or vulnerable in some network environments. It is thus important to control read access (e.g., via get, get-config, or notification) to these data nodes. These are the subtrees and data nodes and their sensitivity/vulnerability:

Changes to the SNMP access control rules should be done either in an atomic way (through a single edit-config or a single commit) or care must be taken that they are done in a sequence that does not open temporarily access to resources. Implementations supporting SNMP write access must ensure that any SNMP access control rule changes over NETCONF are atomic as well to the SNMP instrumentation. In particular changes involving an internal delete/create cycle (e.g., to move a user to a different group) must be done with sufficient protections such that even a power fail immediately after the delete does not leave the administrator locked out.

Security administrators need to ensure that NETCONF access control rules and SNMP access control rules implement a consistent security policy. Specifically, the SNMP access control rules should prevent accidental leakage of sensitive security parameters such as community strings. See the Security Considerations section of [RFC3584] for further details.

7. Acknowledgments

The authors want to thank Wes Hardaker and David Spakes for their detailed reviews. Additional valuable comments were provided by David Harrington, Borislav Lukovic and Randy Presuhn.

Juergen Schoenwaelder was partly funded by Flamingo, a Network of Excellence project (ICT-318488) supported by the European Commission under its Seventh Framework Programme.

8. References

8.1. Normative References

[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC6020] Bjorklund, M., "YANG - A Data Modeling Language for the Network Configuration Protocol (NETCONF)", RFC 6020, October 2010.
[RFC6241] Enns, R., Bjorklund, M., Schoenwaelder, J. and A. Bierman, "Network Configuration Protocol (NETCONF)", RFC 6241, June 2011.
[RFC6242] Wasserman, M., "Using the NETCONF Protocol over Secure Shell (SSH)", RFC 6242, June 2011.
[RFC6536] Bierman, A. and M. Bjorklund, "Network Configuration Protocol (NETCONF) Access Control Model", RFC 6536, March 2012.
[RFC6991] Schoenwaelder, J., "Common YANG Data Types", RFC 6991, July 2013.

8.2. Informative References

[RFC3411] Harrington, D., Presuhn, R. and B. Wijnen, "An Architecture for Describing Simple Network Management Protocol (SNMP) Management Frameworks", STD 62, RFC 3411, December 2002.
[RFC3412] Case, J., Harrington, D., Presuhn, R. and B. Wijnen, "Message Processing and Dispatching for the Simple Network Management Protocol (SNMP)", STD 62, RFC 3412, December 2002.
[RFC3413] Levi, D., Meyer, P. and B. Stewart, "Simple Network Management Protocol (SNMP) Applications", STD 62, RFC 3413, December 2002.
[RFC3414] Blumenthal, U. and B. Wijnen, "User-based Security Model (USM) for version 3 of the Simple Network Management Protocol (SNMPv3)", STD 62, RFC 3414, December 2002.
[RFC3415] Wijnen, B., Presuhn, R. and K. McCloghrie, "View-based Access Control Model (VACM) for the Simple Network Management Protocol (SNMP)", STD 62, RFC 3415, December 2002.
[RFC3418] Presuhn, R., "Management Information Base (MIB) for the Simple Network Management Protocol (SNMP)", STD 62, RFC 3418, December 2002.
[RFC3584] Frye, R., Levi, D., Routhier, S. and B. Wijnen, "Coexistence between Version 1, Version 2, and Version 3 of the Internet-standard Network Management Framework", BCP 74, RFC 3584, August 2003.
[RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688, January 2004.
[RFC5591] Harrington, D. and W. Hardaker, "Transport Security Model for the Simple Network Management Protocol (SNMP)", RFC 5591, June 2009.
[RFC5592] Harrington, D., Salowey, J. and W. Hardaker, "Secure Shell Transport Model for the Simple Network Management Protocol (SNMP)", RFC 5592, June 2009.
[RFC6353] Hardaker, W., "Transport Layer Security (TLS) Transport Model for the Simple Network Management Protocol (SNMP)", RFC 6353, July 2011.
[RFC6643] Schoenwaelder, J., "Translation of Structure of Management Information Version 2 (SMIv2) MIB Modules to YANG Modules", RFC 6643, July 2012.

Appendix A. Example configurations

A.1. Engine Configuration Example

Below is an XML instance document showing a configuration of an SNMP engine listening on UDP port 161 on IPv4 and IPv6 endpoints and accepting SNMPv2c and SNMPv3 messages.

<snmp xmlns="urn:ietf:params:xml:ns:yang:ietf-snmp">
  <engine>
    <enabled>true</enabled>
    <listen>
      <name>all-ipv4-udp</name>
      <udp>
        <ip>0.0.0.0</ip>
        <port>161</port>
      </udp>
    </listen>
    <listen>
      <name>all-ipv6-udp</name>
      <udp>
        <ip>::</ip>
        <port>161</port>
      </udp>
    </listen>
    <version>
      <v2c/>
      <v3/>
    </version>
    <engine-id>80:00:02:b8:04:61:62:63</engine-id>
  </engine>
</snmp>
	    

A.2. Community Configuration Example

Below is an XML instance document showing a configuration that maps the community name "public" to the security-name "community‑public" on the local engine with the default context name. The target tag "community‑public‑access" filters the access to this community name.

<snmp xmlns="urn:ietf:params:xml:ns:yang:ietf-snmp">
  <community>
    <index>1</index>
    <text-name>public</text-name>
    <security-name>community-public</security-name>
    <target-tag>community-public-access</target-tag>
  </community>
  <target>
    <name>management-station</name>
    <udp>
      <ip>2001:db8::abcd</ip>
      <port>161</port>
    </udp>
    <tag>blue</tag>
    <tag>community-public-access</tag>
    <target-params>v2c-public</target-params>
  </target>
  <target-params>
    <name>v2c-public</name>
    <v2c>
      <security-name>community-public</security-name>
    </v2c>
  </target-params>
</snmp>
	    

A.3. User-based Security Model Configuration Example

Below is an XML instance document showing the configuration of a local user "joey" who has no authentication or privacy keys. For the remote SNMP engine identified by the snmpEngineID '800002b804616263'H, two users are configure. The user "matt" has a localized SHA authentication key and the user "russ" has a localized SHA authentication key and an AES encryption key.

<snmp xmlns="urn:ietf:params:xml:ns:yang:ietf-snmp">
  <usm>
    <local>
      <user>
        <name>joey</name>
      </user>
    </local>
    <remote>
      <engine-id>00:00:00:00:00:00:00:00:00:00:00:02</engine-id>
      <user>
        <name>matt</name>
        <auth>
          <sha>
            <!--
                The 'key' value is split into two lines to match
                the RFC formatting rules.
            -->
            <key>66:95:fe:bc:92:88:e3:62:82:23:
                 5f:c7:15:1f:12:84:97:b3:8f:3f</key>
          </sha>
        </auth>
      </user>
      <user>
        <name>russ</name>
        <auth>
          <sha>
            <!--
                The 'key' value is split into two lines to match
                the RFC formatting rules.
            -->
            <key>66:95:fe:bc:92:88:e3:62:82:23:
                 5f:c7:15:1f:12:84:97:b3:8f:3f</key>
          </sha>
        </auth>
        <priv>
          <aes>
            <!--
                The 'key' value is split into two lines to match
                the RFC formatting rules.
            -->
            <key>66:95:fe:bc:92:88:e3:62:82:23:
                 5f:c7:15:1f:12:84</key>
          </aes>
        </priv>
      </user>
    </remote>
  </usm>
  <target>
    <name>bluebox</name>
    <udp>
      <ip>2001:db8::abcd</ip>
      <port>161</port>
    </udp>
    <tag>blue</tag>
    <target-params>matt-auth</target-params>
  </target>
  <target-params>
    <name>matt-auth</name>
    <usm>
      <user-name>matt</user-name>
      <security-level>auth-no-priv</security-level>
    </usm>
  </target-params>
</snmp>
	    

A.4. Target and Notification Configuration Example

Below is an XML instance document showing the configuration of a notification generator application (see Appendix A of [RFC3413]). Note that the USM specific objects are defined in the ietf-snmp-usm.yang submodule.

<snmp xmlns="urn:ietf:params:xml:ns:yang:ietf-snmp">
  <target>
    <name>addr1</name>
    <udp>
      <ip>192.0.2.3</ip>
      <port>162</port>
    </udp>
    <tag>group1</tag>
    <target-params>joe-auth</target-params>
  </target>
  <target>
    <name>addr2</name>
    <udp>
      <ip>192.0.2.6</ip>
      <port>162</port>
    </udp>
    <tag>group1</tag>
    <target-params>joe-auth</target-params>
  </target>
  <target>
    <name>addr3</name>
    <udp>
      <ip>192.0.2.9</ip>
      <port>162</port>
    </udp>
    <tag>group2</tag>
    <target-params>bob-priv</target-params>
  </target>
  <target-params>
    <name>joe-auth</name>
    <usm>
      <user-name>joe</user-name>
      <security-level>auth-no-priv</security-level>
    </usm>
  </target-params>
  <target-params>
    <name>bob-priv</name>
    <usm>
      <user-name>bob</user-name>
      <security-level>auth-priv</security-level>
    </usm>
  </target-params>
  <notify>
    <name>group1</name>
    <tag>group1</tag>
    <type>trap</type>
  </notify>
  <notify>
    <name>group2</name>
    <tag>group2</tag>
    <type>trap</type>
  </notify>
</snmp>
	    

A.5. Proxy Configuration Example

Below is an XML instance document showing the configuration of a proxy forwarder application. It proxies SNMPv2c messages from command generators to a file server running a SNMPv1 agent that recognizes two community strings, "private" and "public", with different associated read views. The fileserver is represented as two "target" instances, one for each community string.

If the proxy receives a SNMPv2c message with the community string "public" from a device in the "Office Network" or "Home Office Network", it gets tagged as "trusted", and the proxy uses the "private" community string when sending the message to the file server. Other SNMPv2c messages with the community string "public" get tagged as "non‑trusted", and the proxy uses the "public" community string for these messages. There is also a special "backdoor" community string that can be used from any location to get "trusted" access.

The "Office Network" and "Home Office Network" are represented as two "target" instances. These "target" instances have target-params "none", which refers to a non-existing target-params entry.

<snmp xmlns="urn:ietf:params:xml:ns:yang:ietf-snmp">
  <target>
    <name>File Server (private)</name>
    <udp>
      <ip>192.0.2.1</ip>
    </udp>
    <target-params>v1-private</target-params>
  </target>
  <target>
    <name>File Server (public)</name>
    <udp>
      <ip>192.0.2.1</ip>
    </udp>
    <target-params>v1-public</target-params>
  </target>
  <target>
    <name>Office Network</name>
    <udp>
      <ip>192.0.2.0</ip>
      <prefix-length>24</prefix-length>
    </udp>
    <tag>office</tag>
    <target-params>none</target-params>
  </target>
  <target>
    <name>Home Office Network</name>
    <udp>
      <ip>203.0.113.0</ip>
      <prefix-length>24</prefix-length>
    </udp>
    <tag>home-office</tag>
    <target-params>none</target-params>
  </target>
  <target-params>
    <name>v1-private</name>
    <v1>
      <security-name>private</security-name>
    </v1>
  </target-params>
  <target-params>
    <name>v1-public</name>
    <v1>
      <security-name>public</security-name>
    </v1>
  </target-params>
  <target-params>
    <name>v2c-public</name>
    <v2c>
      <security-name>public</security-name>
    </v2c>
  </target-params>

  <!--
      Communities c1,c2,c3, and c4 are used for incoming messages
      that should be forwarded.

      Communities c3 and c5 are used for outgoing messages to the
      file server.
  -->
  <community>
    <index>c1</index>
    <security-name>public</security-name>
    <engine-id>80:00:61:81:c8</engine-id>
    <context>trusted</context>
    <target-tag>office</target-tag>
  </community>
  <community>
    <index>c2</index>
    <security-name>public</security-name>
    <engine-id>80:00:61:81:c8</engine-id>
    <context>trusted</context>
    <target-tag>home-office</target-tag>
  </community>
  <community>
    <index>c3</index>
    <security-name>public</security-name>
    <engine-id>80:00:61:81:c8</engine-id>
    <context>not-trusted</context>
  </community>
  <community>
    <index>c4</index>
    <text-name>backdoor</text-name>
    <security-name>public</security-name>
    <engine-id>80:00:61:81:c8</engine-id>
    <context>trusted</context>
  </community>
  <community>
    <index>c5</index>
    <security-name>private</security-name>
    <engine-id>80:00:61:81:c8</engine-id>
    <context>trusted</context>
  </community>

  <proxy>
    <name>p1</name>
    <type>read</type>
    <context-engine-id>80:00:61:81:c8</context-engine-id>
    <context-name>trusted</context-name>
    <target-params-in>v2c-public</target-params-in>
    <single-target-out>File Server (private)</single-target-out>
  </proxy>
  <proxy>
    <name>p2</name>
    <type>read</type>
    <context-engine-id>80:00:61:81:c8</context-engine-id>
    <context-name>not-trusted</context-name>
    <target-params-in>v2c-public</target-params-in>
    <single-target-out>File Server (public)</single-target-out>
  </proxy>
</snmp>
	    

If an SNMPv2c Get request with community string "public" is received from an IP address tagged as "office" or "home‑office", or if the request is received from anywhere else with community string "backdoor", the implied context is "trusted" and so proxy entry "p1" matches. The request is forwarded to the file server as SNMPv1 with community "private" using community table entry "c5" for outbound params lookup.

If an SNMPv2c Get request with community string "public" is received from any other IP address, the implied context is "not‑trusted" so proxy entry "p2" matches, and the request is forwarded to the file server as SNMPv1 with community "public".

A.6. View-based Access Control Model Configuration Example

Below is an XML instance document showing the minimum-secure VACM configuration (see Appendix A of [RFC3415]).

<snmp xmlns="urn:ietf:params:xml:ns:yang:ietf-snmp">
  <vacm>
    <group>
      <name>initial</name>
      <member>
        <security-name>initial</security-name>
        <security-model>usm</security-model>
      </member>
      <access>
        <context></context>
        <security-model>usm</security-model>
        <security-level>no-auth-no-priv</security-level>
        <read-view>restricted</read-view>
        <notify-view>restricted</notify-view>
      </access>
      <access>
        <context></context>
        <security-model>usm</security-model>
        <security-level>auth-no-priv</security-level>
        <read-view>internet</read-view>
        <write-view>internet</write-view>
        <notify-view>internet</notify-view>
      </access>
    </group>
    <view>
      <name>initial</name>
      <include>1.3.6.1</include>
    </view>
    <view>
      <name>restricted</name>
      <include>1.3.6.1</include>
    </view>
  </vacm>
</snmp>
	    

The following XML instance document shows the semi-secure VACM configuration (only the view configuration is different).

<snmp xmlns="urn:ietf:params:xml:ns:yang:ietf-snmp">
  <vacm>
    <group>
      <name>initial</name>
      <member>
        <security-name>initial</security-name>
        <security-model>usm</security-model>
      </member>
      <access>
        <context></context>
        <security-model>usm</security-model>
        <security-level>no-auth-no-priv</security-level>
        <read-view>restricted</read-view>
        <notify-view>restricted</notify-view>
      </access>
      <access>
        <context></context>
        <security-model>usm</security-model>
        <security-level>auth-no-priv</security-level>
        <read-view>internet</read-view>
        <write-view>internet</write-view>
        <notify-view>internet</notify-view>
      </access>
    </group>
    <view>
      <name>initial</name>
      <include>1.3.6.1</include>
    </view>
    <view>
      <name>restricted</name>
      <include>1.3.6.1.2.1.1</include>
      <include>1.3.6.1.2.1.11</include>
      <include>1.3.6.1.6.3.10.2.1</include>
      <include>1.3.6.1.6.3.11.2.1</include>
      <include>1.3.6.1.6.3.15.1.1</include>
    </view>
  </vacm>
</snmp>
	    

A.7. Transport Layer Security Transport Model Configuration Example

Below is an XML instance document showing the configuration of the certificate to security name mapping (see Appendix A.2 and A.3 of [RFC6353]).

<snmp xmlns="urn:ietf:params:xml:ns:yang:ietf-snmp"
      xmlns:x509c2n=
        "urn:ietf:params:xml:ns:yang:ietf-x509-cert-to-name">
  <tlstm>
    <cert-to-name>
      <id>1</id>
      <fingerprint>11:0A:05:11:00</fingerprint>
      <map-type>x509c2n:san-any</map-type>
    </cert-to-name>
    <cert-to-name>
      <id>2</id>
      <fingerprint>11:0A:05:11:00</fingerprint>
      <map-type>x509c2n:specified</map-type>
      <name>
        Joe Cool
      </name>
    </cert-to-name>
  </tlstm>
</snmp>	    

Authors' Addresses

Martin Bjorklund Tail-f Systems EMail: mbj@tail-f.com
Juergen Schoenwaelder Jacobs University EMail: j.schoenwaelder@jacobs-university.de