rfc7407
Internet Engineering Task Force (IETF) M. Bjorklund
Request for Comments: 7407 Tail-f Systems
Category: Standards Track J. Schoenwaelder
ISSN: 2070-1721 Jacobs University
December 2014
A YANG Data Model for SNMP Configuration
Abstract
This document defines a collection of YANG definitions for
configuring SNMP engines.
Status of This Memo
This is an Internet Standards Track document.
This document is a product of the Internet Engineering Task Force
(IETF). It represents the consensus of the IETF community. It has
received public review and has been approved for publication by the
Internet Engineering Steering Group (IESG). Further information on
Internet Standards is available in Section 2 of RFC 5741.
Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
http://www.rfc-editor.org/info/rfc7407.
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.
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RFC 7407 YANG Data Model for SNMP Configuration December 2014
Table of Contents
1. Introduction ....................................................3
2. Data Model ......................................................3
2.1. Tree Diagrams ..............................................4
2.2. General Considerations .....................................4
2.3. Common Definitions .........................................4
2.4. Engine Configuration .......................................5
2.5. Target Configuration .......................................6
2.6. Notification Configuration .................................7
2.7. Proxy Configuration ........................................8
2.8. Community Configuration ....................................8
2.9. View-Based Access Control Model Configuration ..............9
2.10. User-Based Security Model Configuration ..................10
2.11. Transport Security Model Configuration ...................11
2.12. Transport Layer Security Transport Model Configuration ...12
2.13. Secure Shell Transport Model Configuration ...............13
3. Implementation Guidelines ......................................14
3.1. Supporting read-only SNMP Access ..........................15
3.2. Supporting read-write SNMP Access .........................15
4. Definitions ....................................................16
4.1. Module 'ietf-x509-cert-to-name' ...........................16
4.2. Module 'ietf-snmp' ........................................22
4.3. Submodule 'ietf-snmp-common' ..............................24
4.4. Submodule 'ietf-snmp-engine' ..............................28
4.5. Submodule 'ietf-snmp-target' ..............................32
4.6. Submodule 'ietf-snmp-notification' ........................36
4.7. Submodule 'ietf-snmp-proxy' ...............................41
4.8. Submodule 'ietf-snmp-community' ...........................44
4.9. Submodule 'ietf-snmp-vacm' ................................49
4.10. Submodule 'ietf-snmp-usm' ................................55
4.11. Submodule 'ietf-snmp-tsm' ................................60
4.12. Submodule 'ietf-snmp-tls' ................................63
4.13. Submodule 'ietf-snmp-ssh' ................................68
5. IANA Considerations ............................................71
6. Security Considerations ........................................72
7. References .....................................................75
7.1. Normative References ......................................75
7.2. Informative References ....................................75
Appendix A. Example Configurations ...............................78
A.1. Engine Configuration Example ..............................78
A.2. Community Configuration Example ...........................78
A.3. User-Based Security Model Configuration Example ...........79
A.4. Target and Notification Configuration Example .............81
A.5. Proxy Configuration Example ...............................82
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A.6. View-Based Access Control Model Configuration Example .....85
A.7. Transport Layer Security Transport Model Configuration
Example ...................................................87
Acknowledgments ...................................................88
Authors' Addresses ................................................88
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], [RFC3417], [RFC3418], [RFC3419], [RFC3584],
[RFC3826], [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 the Network
Configuration Protocol (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 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 explicitly modeled. The operational state of an SNMP
agent can be accessed either 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 an 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.
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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:
o Brackets "[" and "]" enclose list keys.
o Abbreviations before data node names: "rw" means configuration
(read-write), and "ro" means state data (read-only).
o Symbols after data node names: "?" means an optional node, "!"
means a presence container, and "*" denotes a list and leaf-list.
o Parentheses enclose choice and case nodes, and case nodes are also
marked with a colon (":").
o Ellipsis ("...") stands for contents of subtrees that are not
shown.
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 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 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.
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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. The Secure Shell (SSH) Protocol, Transport
Layer Security (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].
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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 submodules specific to the security model, currently,
"ietf-snmp-community" (Section 2.8), "ietf-snmp-usm" (Section 2.10),
and "ietf-snmp-tls" (Section 2.12).
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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
This submodule 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].
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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
This submodule also augments the "/snmp/target-params/params" choice
with nodes for the Community-based Security Model used by SNMPv1 and
SNMPv2c:
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+--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 an
snmpTargetParamsMPModel 0 (SNMPv1) or 1 (SNMPv2), and an
snmpTargetParamsSecurityModel 1 (SNMPv1) or 2 (SNMPv2), respectively.
Both cases imply an 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? view-name
+--rw view* [name]
+--rw name view-name
+--rw include* snmp:wildcard-object-identifier
+--rw exclude* snmp:wildcard-object-identifier
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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
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This submodule 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
This submodule 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].
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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
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This submodule 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
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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 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.
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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 to 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 they may be copied into "running".
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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 an X.509 certificate.
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The algorithm used to extract a name from an 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 7407; see
the RFC itself for full legal notices.";
reference
"RFC 6353: Transport Layer Security (TLS) Transport Model for
the Simple Network Management Protocol (SNMP)";
revision 2014-12-10 {
description
"Initial revision.";
reference
"RFC 7407: 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.
A 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
"RFC 6353: Transport Layer Security (TLS) Transport Model
for the Simple Network Management Protocol (SNMP).
SNMP-TLS-TM-MIB.SnmpTLSFingerprint";
}
Bjorklund & Schoenwaelder Standards Track [Page 17]
RFC 7407 YANG Data Model for SNMP Configuration December 2014
/* 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 the cert-to-name list is
used.";
reference
"RFC 6353: Transport Layer Security (TLS) Transport Model
for the Simple Network Management Protocol (SNMP).
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
"RFC 6353: Transport Layer Security (TLS) Transport Model
for the Simple Network Management Protocol (SNMP).
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
"RFC 6353: Transport Layer Security (TLS) Transport Model
for the Simple Network Management Protocol (SNMP).
SNMP-TLS-TM-MIB.snmpTlstmCertSANDNSName";
}
Bjorklund & Schoenwaelder Standards Track [Page 18]
RFC 7407 YANG Data Model for SNMP Configuration December 2014
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
"RFC 6353: Transport Layer Security (TLS) Transport Model
for the Simple Network Management Protocol (SNMP).
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
"RFC 6353: Transport Layer Security (TLS) Transport Model
for the Simple Network Management Protocol (SNMP).
SNMP-TLS-TM-MIB.snmpTlstmCertSANAny";
Bjorklund & Schoenwaelder Standards Track [Page 19]
RFC 7407 YANG Data Model for SNMP Configuration December 2014
}
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
"RFC 6353: Transport Layer Security (TLS) Transport Model
for the Simple Network Management Protocol (SNMP).
SNMP-TLS-TM-MIB.snmpTlstmCertCommonName";
}
/*
* Groupings
*/
grouping cert-to-name {
description
"Defines nodes for mapping certificates to names. Modules
that use 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 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 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
Bjorklund & Schoenwaelder Standards Track [Page 20]
RFC 7407 YANG Data Model for SNMP Configuration December 2014
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 to look 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 certificates' subjectAltName fields to map directly to
a name via a 1:1 transformation.";
reference
"RFC 6353: Transport Layer Security (TLS) Transport Model
for the Simple Network Management Protocol (SNMP).
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
"RFC 6353: Transport Layer Security (TLS) Transport Model
for the Simple Network Management Protocol
(SNMP).
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
"RFC 6353: Transport Layer Security (TLS) Transport Model
for the Simple Network Management Protocol
(SNMP).
SNMP-TLS-TM-MIB.snmpTlstmCertToTSNFingerprint";
}
leaf map-type {
type identityref {
base cert-to-name;
Bjorklund & Schoenwaelder Standards Track [Page 21]
RFC 7407 YANG Data Model for SNMP Configuration December 2014
}
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
"RFC 6353: Transport Layer Security (TLS) Transport Model
for the Simple Network Management Protocol
(SNMP).
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
"RFC 6353: Transport Layer Security (TLS) Transport Model
for the Simple Network Management Protocol
(SNMP).
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;
include ietf-snmp-common {
revision-date 2014-12-10;
}
include ietf-snmp-engine {
Bjorklund & Schoenwaelder Standards Track [Page 22]
RFC 7407 YANG Data Model for SNMP Configuration December 2014
revision-date 2014-12-10;
}
include ietf-snmp-target {
revision-date 2014-12-10;
}
include ietf-snmp-notification {
revision-date 2014-12-10;
}
include ietf-snmp-proxy {
revision-date 2014-12-10;
}
include ietf-snmp-community {
revision-date 2014-12-10;
}
include ietf-snmp-usm {
revision-date 2014-12-10;
}
include ietf-snmp-tsm {
revision-date 2014-12-10;
}
include ietf-snmp-vacm {
revision-date 2014-12-10;
}
include ietf-snmp-tls {
revision-date 2014-12-10;
}
include ietf-snmp-ssh {
revision-date 2014-12-10;
}
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>";
Bjorklund & Schoenwaelder Standards Track [Page 23]
RFC 7407 YANG Data Model for SNMP Configuration December 2014
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 7407; see
the RFC itself for full legal notices.";
revision 2014-12-10 {
description
"Initial revision.";
reference
"RFC 7407: 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>
Bjorklund & Schoenwaelder Standards Track [Page 24]
RFC 7407 YANG Data Model for SNMP Configuration December 2014
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 7407; see
the RFC itself for full legal notices.";
revision 2014-12-10 {
description
"Initial revision.";
reference
"RFC 7407: A YANG Data Model for SNMP Configuration";
}
/* Collection of SNMP-specific data types */
typedef admin-string {
type string {
length "0..255";
}
description
"Represents SnmpAdminString as defined in RFC 3411.
Note that the size of an SnmpAdminString is measured in
octets, not characters.";
Bjorklund & Schoenwaelder Standards Track [Page 25]
RFC 7407 YANG Data Model for SNMP Configuration December 2014
reference
"RFC 3411: An Architecture for Describing Simple Network
Management Protocol (SNMP) Management Frameworks.
SNMP-FRAMEWORK-MIB.SnmpAdminString";
}
typedef identifier {
type admin-string {
length "1..32";
}
description
"Identifiers are used to name items in the SNMP configuration
datastore.";
}
typedef context-name {
type admin-string {
length "0..32";
}
description
"The context type represents an SNMP context name.";
reference
"RFC 3411: An Architecture for Describing Simple Network
Management Protocol (SNMP) Management Frameworks";
}
typedef security-name {
type admin-string {
length "1..32";
}
description
"The security-name type represents an SNMP security name.";
reference
"RFC 3411: An Architecture for Describing Simple Network
Management Protocol (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";
}
Bjorklund & Schoenwaelder Standards Track [Page 26]
RFC 7407 YANG Data Model for SNMP Configuration December 2014
}
reference
"RFC 3411: An Architecture for Describing Simple Network
Management Protocol (SNMP) Management Frameworks";
}
typedef security-model-or-any {
type union {
type enumeration {
enum any { value 0; }
}
type security-model;
}
reference
"RFC 3411: An Architecture for Describing Simple Network
Management Protocol (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
"RFC 3411: An Architecture for Describing Simple Network
Management Protocol (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
hexadecimal octets, e.g., '80:00:02:b8:04:61:62:63'.";
reference
"RFC 3411: An Architecture for Describing Simple Network
Management Protocol (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 an asterisk
('*').";
Bjorklund & Schoenwaelder Standards Track [Page 27]
RFC 7407 YANG Data Model for SNMP Configuration December 2014
}
typedef tag-value {
type string {
length "0..255";
}
description
"Represents SnmpTagValue as defined in RFC 3413.
Note that the size of an SnmpTagValue is measured in
octets, not characters.";
reference
"RFC 3413: Simple Network Management Protocol (SNMP)
Applications.
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/>
Bjorklund & Schoenwaelder Standards Track [Page 28]
RFC 7407 YANG Data Model for SNMP Configuration December 2014
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 7407; see
the RFC itself for full legal notices.";
revision 2014-12-10 {
description
"Initial revision.";
reference
"RFC 7407: 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
Bjorklund & Schoenwaelder Standards Track [Page 29]
RFC 7407 YANG Data Model for SNMP Configuration December 2014
"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.";
}
}
}
}
}
Bjorklund & Schoenwaelder Standards Track [Page 30]
RFC 7407 YANG Data Model for SNMP Configuration December 2014
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
"RFC 3411: An Architecture for Describing Simple Network
Management Protocol (SNMP) Management
Frameworks.
SNMP-FRAMEWORK-MIB.snmpEngineID";
}
leaf enable-authen-traps {
type boolean;
description
"Indicates whether the SNMP entity is permitted to
generate authenticationFailure traps.";
reference
"RFC 3418: Management Information Base (MIB) for the
Simple Network Management Protocol (SNMP)
SNMPv2-MIB.snmpEnableAuthenTraps";
}
}
}
}
<CODE ENDS>
Bjorklund & Schoenwaelder Standards Track [Page 31]
RFC 7407 YANG Data Model for SNMP Configuration December 2014
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).
Bjorklund & Schoenwaelder Standards Track [Page 32]
RFC 7407 YANG Data Model for SNMP Configuration December 2014
This version of this YANG module is part of RFC 7407; see
the RFC itself for full legal notices.";
reference
"RFC 3413: Simple Network Management Protocol (SNMP)
Applications";
revision 2014-12-10 {
description
"Initial revision.";
reference
"RFC 7407: A YANG Data Model for SNMP Configuration";
}
augment /snmp:snmp {
list target {
key name;
description
"List of targets.";
reference
"RFC 3413: Simple Network Management Protocol (SNMP)
Applications.
SNMP-TARGET-MIB.snmpTargetAddrTable";
leaf name {
type snmp:identifier;
description
"Identifies the target.";
reference
"RFC 3413: Simple Network Management Protocol (SNMP)
Applications.
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.";
Bjorklund & Schoenwaelder Standards Track [Page 33]
RFC 7407 YANG Data Model for SNMP Configuration December 2014
reference
"RFC 3413: Simple Network Management Protocol (SNMP)
Applications.
SNMP-TARGET-MIB.snmpTargetAddrTDomain
SNMP-TARGET-MIB.snmpTargetAddrTAddress";
case udp {
reference
"RFC 3417: Transport Mappings for the Simple Network
Management Protocol (SNMP).
SNMPv2-TM.snmpUDPDomain
RFC 3419: Textual Conventions for Transport Addresses.
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
"RFC 3413: Simple Network Management Protocol (SNMP).
SNMP-TARGET-MIB.snmpTargetAddrTAddress";
}
leaf port {
type inet:port-number;
default 162;
description
"UDP port number.";
reference
"RFC 3413: Simple Network Management Protocol (SNMP).
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.";
Bjorklund & Schoenwaelder Standards Track [Page 34]
RFC 7407 YANG Data Model for SNMP Configuration December 2014
reference
"RFC 3584: Coexistence between Version 1, Version 2,
and Version 3 of the Internet-standard
Network Management Framework.
SNMP-COMMUNITY-MIB.snmpTargetAddrTMask";
}
}
}
}
leaf-list tag {
type snmp:tag-value;
description
"List of tag values used to select target addresses.";
reference
"RFC 3413: Simple Network Management Protocol (SNMP).
Applications.
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
"RFC 3413: Simple Network Management Protocol (SNMP).
Applications.
SNMP-TARGET-MIB.snmpTargetAddrTimeout";
}
leaf retries {
type uint8;
default 3;
description
"Needed only if this target can receive
InformRequest-PDUs.";
reference
"RFC 3413: Simple Network Management Protocol (SNMP).
Applications.
SNMP-TARGET-MIB.snmpTargetAddrRetryCount";
}
leaf target-params {
type snmp:identifier;
mandatory true;
reference
"RFC 3413: Simple Network Management Protocol (SNMP).
Applications.
SNMP-TARGET-MIB.snmpTargetAddrParams";
Bjorklund & Schoenwaelder Standards Track [Page 35]
RFC 7407 YANG Data Model for SNMP Configuration December 2014
}
}
list target-params {
key name;
description
"List of target parameters.";
reference
"RFC 3413: Simple Network Management Protocol (SNMP).
Applications.
SNMP-TARGET-MIB.snmpTargetParamsTable";
leaf name {
type snmp:identifier;
}
choice params {
description
"This choice is augmented with case nodes containing
configuration parameters specific to the security model.";
}
}
}
}
<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>
Bjorklund & Schoenwaelder Standards Track [Page 36]
RFC 7407 YANG Data Model for SNMP Configuration December 2014
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 7407; see
the RFC itself for full legal notices.";
reference
"RFC 3413: Simple Network Management Protocol (SNMP)
Applications";
revision 2014-12-10 {
description
"Initial revision.";
reference
"RFC 7407: A YANG Data Model for SNMP Configuration";
}
feature notification-filter {
description
"A server implements this feature if it supports SNMP
notification filtering.";
reference
"RFC 3413: Simple Network Management Protocol (SNMP)
Applications";
}
augment /snmp:snmp {
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list notify {
key name;
description
"Targets that will receive notifications.
Entries in this list are mapped 1-1 to entries in
snmpNotifyTable, except that if an entry in snmpNotifyTable
has an snmpNotifyTag for which no snmpTargetAddrEntry
exists, then the snmpNotifyTable entry is not mapped to an
entry in this list.";
reference
"RFC 3413: Simple Network Management Protocol (SNMP).
Applications.
SNMP-NOTIFICATION-MIB.snmpNotifyTable";
leaf name {
type snmp:identifier;
description
"An arbitrary name for the list entry.";
reference
"RFC 3413: Simple Network Management Protocol (SNMP).
Applications.
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
"RFC 3413: Simple Network Management Protocol (SNMP).
Applications.
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.";
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RFC 7407 YANG Data Model for SNMP Configuration December 2014
reference
"RFC 3413: Simple Network Management Protocol (SNMP).
Applications.
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 items, 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
"RFC 3413: Simple Network Management Protocol (SNMP).
Applications.
SNMP-NOTIFICATION-MIB.snmpNotifyFilterProfileTable
SNMP-NOTIFICATION-MIB.snmpNotifyFilterTable";
leaf name {
type snmp:identifier;
description
"Name of the filter profile.";
reference
"RFC 3413: Simple Network Management Protocol (SNMP).
Applications.
SNMP-NOTIFICATION-MIB.snmpNotifyFilterProfileName";
}
leaf-list include {
type snmp:wildcard-object-identifier;
description
"A family of subtrees included in this filter.";
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reference
"RFC 3413: Simple Network Management Protocol (SNMP).
Applications.
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
"RFC 3413: Simple Network Management Protocol (SNMP).
Applications.
SNMP-NOTIFICATION-MIB.snmpNotifyFilterSubtree
SNMP-NOTIFICATION-MIB.snmpNotifyFilterMask
SNMP-NOTIFICATION-MIB.snmpNotifyFilterType";
}
}
}
augment /snmp:snmp/snmp:target-params {
reference
"RFC 3413: Simple Network Management Protocol (SNMP).
Applications.
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
"RFC 3413: Simple Network Management Protocol (SNMP).
Applications.
SNMP-NOTIFICATION-MIB.snmpNotifyFilterProfileName";
}
}
}
<CODE ENDS>
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RFC 7407 YANG Data Model for SNMP Configuration December 2014
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 7407; see
the RFC itself for full legal notices.";
Bjorklund & Schoenwaelder Standards Track [Page 41]
RFC 7407 YANG Data Model for SNMP Configuration December 2014
reference
"RFC 3413: Simple Network Management Protocol (SNMP)
Applications";
revision 2014-12-10 {
description
"Initial revision.";
reference
"RFC 7407: A YANG Data Model for SNMP Configuration";
}
feature proxy {
description
"A server implements this feature if it can act as an
SNMP proxy.";
reference
"RFC 3413: Simple Network Management Protocol (SNMP)
Applications";
}
augment /snmp:snmp {
if-feature snmp:proxy;
list proxy {
key name;
description
"List of proxy parameters.";
reference
"RFC 3413: Simple Network Management Protocol (SNMP).
Applications.
SNMP-PROXY-MIB.snmpProxyTable";
leaf name {
type snmp:identifier;
description
"Identifies the proxy parameter entry.";
reference
"RFC 3413: Simple Network Management Protocol (SNMP).
Applications.
SNMP-PROXY-MIB.snmpProxyName";
}
leaf type {
type enumeration {
enum read { value 1; }
enum write { value 2; }
enum trap { value 3; }
enum inform { value 4; }
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}
mandatory true;
reference
"RFC 3413: Simple Network Management Protocol (SNMP).
Applications.
SNMP-PROXY-MIB.snmpProxyType";
}
leaf context-engine-id {
type snmp:engine-id;
mandatory true;
reference
"RFC 3413: Simple Network Management Protocol (SNMP).
Applications.
SNMP-PROXY-MIB.snmpProxyContextEngineID";
}
leaf context-name {
type snmp:context-name;
reference
"RFC 3413: Simple Network Management Protocol (SNMP).
Applications.
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
"RFC 3413: Simple Network Management Protocol (SNMP).
Applications.
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
"RFC 3413: Simple Network Management Protocol (SNMP).
Applications.
SNMP-PROXY-MIB.snmpProxySingleTargetOut";
}
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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
"RFC 3413: Simple Network Management Protocol (SNMP).
Applications.
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>
Bjorklund & Schoenwaelder Standards Track [Page 44]
RFC 7407 YANG Data Model for SNMP Configuration December 2014
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 7407; see
the RFC itself for full legal notices.";
reference
"RFC 3584: Coexistence between Version 1, Version 2, and
Version 3 of the Internet-standard Network
Management Framework";
revision 2014-12-10 {
description
"Initial revision.";
reference
"RFC 7407: A YANG Data Model for SNMP Configuration";
}
augment /snmp:snmp {
list community {
key index;
description
"List of communities.";
reference
"RFC 3584: Coexistence between Version 1, Version 2,
and Version 3 of the Internet-standard
Network Management Framework.
SNMP-COMMUNITY-MIB.snmpCommunityTable";
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leaf index {
type snmp:identifier;
description
"Index into the community list.";
reference
"RFC 3584: Coexistence between Version 1, Version 2,
and Version 3 of the Internet-standard
Network Management Framework.
SNMP-COMMUNITY-MIB.snmpCommunityIndex";
}
choice name {
nacm:default-deny-all;
description
"The community name, specified as either a string or
a binary value. 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
"RFC 3584: Coexistence between Version 1, Version 2,
and Version 3 of the Internet-standard
Network Management Framework.
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
"RFC 3584: Coexistence between Version 1, Version 2,
and Version 3 of the Internet-standard
Network Management Framework.
SNMP-COMMUNITY-MIB.snmpCommunitySecurityName";
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}
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
"RFC 3584: Coexistence between Version 1, Version 2,
and Version 3 of the Internet-standard
Network Management Framework.
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
"RFC 3584: Coexistence between Version 1, Version 2,
and Version 3 of the Internet-standard
Network Management Framework.
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
"RFC 3584: Coexistence between Version 1, Version 2,
and Version 3 of the Internet-standard
Network Management Framework.
SNMP-COMMUNITY-MIB.snmpCommunityTransportTag";
}
}
}
grouping v1-target-params {
container v1 {
description
"SNMPv1 parameters type.
Represents snmpTargetParamsMPModel '0',
Bjorklund & Schoenwaelder Standards Track [Page 47]
RFC 7407 YANG Data Model for SNMP Configuration December 2014
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
"RFC 3413: Simple Network Management Protocol (SNMP).
Applications.
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
"RFC 3413: Simple Network Management Protocol (SNMP).
Applications.
SNMP-TARGET-MIB.snmpTargetParamsSecurityName";
}
}
}
augment /snmp:snmp/snmp:target-params/snmp:params {
case v1 {
uses v1-target-params;
}
case v2c {
uses v2c-target-params;
}
}
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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
"RFC 3584: Coexistence between Version 1, Version 2,
and Version 3 of the Internet-standard
Network Management Framework.
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>
Bjorklund & Schoenwaelder Standards Track [Page 49]
RFC 7407 YANG Data Model for SNMP Configuration December 2014
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 7407; see
the RFC itself for full legal notices.";
reference
"RFC 3415: View-based Access Control Model (VACM) for the
Simple Network Management Protocol (SNMP)";
revision 2014-12-10 {
description
"Initial revision.";
reference
"RFC 7407: 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.";
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}
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
"RFC 3415: View-based Access Control Model (VACM) for the
Simple Network Management Protocol (SNMP).
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
"RFC 3415: View-based Access Control Model (VACM) for the
Simple Network Management Protocol (SNMP).
SNMP-VIEW-BASED-ACM-MIB.vacmGroupName";
}
list member {
key "security-name";
description
"A member of this VACM group.
A specific combination of security-name and
security-model MUST NOT be present in more than
one group.";
reference
"RFC 3415: View-based Access Control Model (VACM) for the
Simple Network Management Protocol (SNMP).
SNMP-VIEW-BASED-ACM-MIB.vacmSecurityToGroupTable";
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leaf security-name {
type snmp:security-name;
description
"The securityName of a group member.";
reference
"RFC 3415: View-based Access Control Model (VACM) for
the Simple Network Management Protocol (SNMP).
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
"RFC 3415: View-based Access Control Model (VACM) for
the Simple Network Management Protocol (SNMP).
SNMP-VIEW-BASED-ACM-MIB.vacmSecurityModel";
}
}
list access {
key "context security-model security-level";
description
"Definition of access right for groups.";
reference
"RFC 3415: View-based Access Control Model (VACM) for
the Simple Network Management Protocol (SNMP).
SNMP-VIEW-BASED-ACM-MIB.vacmAccessTable";
leaf context {
type snmp:context-name;
description
"The context (prefix) under which the access rights
apply.";
reference
"RFC 3415: View-based Access Control Model (VACM) for
the Simple Network Management Protocol (SNMP).
SNMP-VIEW-BASED-ACM-MIB.vacmAccessContextPrefix";
}
leaf context-match {
type enumeration {
enum exact { value 1; }
enum prefix { value 2; }
}
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RFC 7407 YANG Data Model for SNMP Configuration December 2014
default exact;
reference
"RFC 3415: View-based Access Control Model (VACM) for
the Simple Network Management Protocol (SNMP).
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
"RFC 3415: View-based Access Control Model (VACM) for
the Simple Network Management Protocol (SNMP).
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
"RFC 3415: View-based Access Control Model (VACM) for
the Simple Network Management Protocol (SNMP).
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
"RFC 3415: View-based Access Control Model (VACM) for
the Simple Network Management Protocol (SNMP).
SNMP-VIEW-BASED-ACM-MIB.vacmAccessReadViewName";
}
leaf write-view {
type view-name;
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RFC 7407 YANG Data Model for SNMP Configuration December 2014
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
"RFC 3415: View-based Access Control Model (VACM) for
the Simple Network Management Protocol (SNMP).
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
"RFC 3415: View-based Access Control Model (VACM) for
the Simple Network Management Protocol (SNMP).
SNMP-VIEW-BASED-ACM-MIB.vacmAccessNotifyViewName";
}
}
}
list view {
key name;
description
"Definition of MIB views.";
reference
"RFC 3415: View-based Access Control Model (VACM) for
the Simple Network Management Protocol (SNMP).
SNMP-VIEW-BASED-ACM-MIB.vacmViewTreeFamilyTable";
leaf name {
type view-name;
description
"The name of this VACM MIB view.";
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reference
"RFC 3415: View-based Access Control Model (VACM) for
the Simple Network Management Protocol (SNMP).
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
"RFC 3415: View-based Access Control Model (VACM) for
the Simple Network Management Protocol (SNMP).
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
"RFC 3415: View-based Access Control Model (VACM) for
the Simple Network Management Protocol (SNMP).
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;
}
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RFC 7407 YANG Data Model for SNMP Configuration December 2014
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 7407; see
the RFC itself for full legal notices.";
Bjorklund & Schoenwaelder Standards Track [Page 56]
RFC 7407 YANG Data Model for SNMP Configuration December 2014
reference
"RFC 3414: User-based Security Model (USM) for version 3 of the
Simple Network Management Protocol (SNMPv3)";
revision 2014-12-10 {
description
"Initial revision.";
reference
"RFC 7407: 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
hexadecimal octets.";
}
}
grouping user-list {
list user {
key "name";
reference
"RFC 3414: User-based Security Model (USM) for version 3
of the Simple Network Management Protocol (SNMPv3).
SNMP-USER-BASED-SM-MIB.usmUserTable";
leaf name {
type snmp:identifier;
reference
"RFC 3414: User-based Security Model (USM) for version 3
of the Simple Network Management Protocol (SNMPv3).
SNMP-USER-BASED-SM-MIB.usmUserName";
}
container auth {
presence "enables authentication";
description
"Enables authentication of the user.";
choice protocol {
mandatory true;
reference
"RFC 3414: User-based Security Model (USM) for version 3
of the Simple Network Management Protocol (SNMPv3).
SNMP-USER-BASED-SM-MIB.usmUserAuthProtocol";
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container md5 {
uses key;
reference
"RFC 3414: User-based Security Model (USM) for
version 3 of the Simple Network Management Protocol
(SNMPv3).
SNMP-USER-BASED-SM-MIB.usmHMACMD5AuthProtocol";
}
container sha {
uses key;
reference
"RFC 3414: User-based Security Model (USM) for
version 3 of the Simple Network Management Protocol
(SNMPv3).
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
"RFC 3414: User-based Security Model (USM) for version 3
of the Simple Network Management Protocol (SNMPv3).
SNMP-USER-BASED-SM-MIB.usmUserPrivProtocol";
container des {
uses key;
reference
"RFC 3414: User-based Security Model (USM) for
version 3 of the Simple Network Management Protocol
(SNMPv3).
SNMP-USER-BASED-SM-MIB.usmDESPrivProtocol";
}
container aes {
uses key;
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reference
"RFC 3826: The Advanced Encryption Standard (AES)
Cipher Algorithm in the SNMP User-based Security
Model.
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
"RFC 3414: User-based Security Model (USM) for version 3
of the Simple Network Management Protocol (SNMPv3).
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;
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RFC 7407 YANG Data Model for SNMP Configuration December 2014
reference
"RFC 3413: Simple Network Management Protocol (SNMP).
Applications.
SNMP-TARGET-MIB.snmpTargetParamsSecurityName";
}
leaf security-level {
type snmp:security-level;
mandatory true;
reference
"RFC 3413: Simple Network Management Protocol (SNMP).
Applications.
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>
Bjorklund & Schoenwaelder Standards Track [Page 60]
RFC 7407 YANG Data Model for SNMP Configuration December 2014
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 7407; see
the RFC itself for full legal notices.";
reference
"RFC 5591: Transport Security Model for the
Simple Network Management Protocol (SNMP)";
revision 2014-12-10 {
description
"Initial revision.";
reference
"RFC 7407: 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
"RFC 5591: Transport Security Model for the
Simple Network Management Protocol (SNMP)";
}
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augment /snmp:snmp {
if-feature tsm;
container tsm {
description
"Configuration of the Transport Security Model.";
leaf use-prefix {
type boolean;
default false;
reference
"RFC 5591: Transport Security Model for the Simple
Network Management Protocol (SNMP).
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
"RFC 3413: Simple Network Management Protocol (SNMP).
Applications.
SNMP-TARGET-MIB.snmpTargetParamsSecurityName";
}
leaf security-level {
type snmp:security-level;
mandatory true;
reference
"RFC 3413: Simple Network Management Protocol (SNMP).
Applications.
SNMP-TARGET-MIB.snmpTargetParamsSecurityLevel";
}
}
}
augment /snmp:snmp/snmp:target-params/snmp:params {
if-feature tsm;
case tsm {
uses tsm-target-params;
}
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}
}
<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>";
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RFC 7407 YANG Data Model for SNMP Configuration December 2014
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 7407; see
the RFC itself for full legal notices.";
reference
"RFC 6353: Transport Layer Security (TLS) Transport Model for
the Simple Network Management Protocol (SNMP)";
revision 2014-12-10 {
description
"Initial revision.";
reference
"RFC 7407: 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
"RFC 6353: 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.";
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RFC 7407 YANG Data Model for SNMP Configuration December 2014
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.";
}
}
}
}
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RFC 7407 YANG Data Model for SNMP Configuration December 2014
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
"RFC 3413: Simple Network Management Protocol (SNMP).
Applications.
SNMP-TARGET-MIB.snmpTargetAddrTAddress
RFC 6353: Transport Layer Security (TLS) Transport Model
for the Simple Network Management Protocol (SNMP).
SNMP-TLS-TM-MIB.SnmpTLSAddress";
}
leaf port {
type inet:port-number;
default 10161;
reference
"RFC 3413: Simple Network Management Protocol (SNMP).
Applications.
SNMP-TARGET-MIB.snmpTargetAddrTAddress
RFC 6353: Transport Layer Security (TLS) Transport Model
for the Simple Network Management Protocol (SNMP).
SNMP-TLS-TM-MIB.SnmpTLSAddress";
}
leaf client-fingerprint {
type x509c2n:tls-fingerprint;
reference
"RFC 6353: Transport Layer Security (TLS) Transport Model
for the Simple Network Management Protocol (SNMP).
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RFC 7407 YANG Data Model for SNMP Configuration December 2014
SNMP-TLS-TM-MIB.snmpTlstmParamsClientFingerprint";
}
leaf server-fingerprint {
type x509c2n:tls-fingerprint;
reference
"RFC 6353: Transport Layer Security (TLS) Transport Model
for the Simple Network Management Protocol (SNMP).
SNMP-TLS-TM-MIB.snmpTlstmAddrServerFingerprint";
}
leaf server-identity {
type snmp:admin-string;
reference
"RFC 6353: Transport Layer Security (TLS) Transport Model
for the Simple Network Management Protocol (SNMP).
SNMP-TLS-TM-MIB.snmpTlstmAddrServerIdentity";
}
}
augment /snmp:snmp/snmp:target/snmp:transport {
if-feature tlstm;
case tls {
reference
"RFC 6353: Transport Layer Security (TLS) Transport Model
for the Simple Network Management Protocol (SNMP).
SNMP-TLS-TM-MIB.snmpTLSTCPDomain";
container tls {
uses tls-transport;
}
}
}
augment /snmp:snmp/snmp:target/snmp:transport {
if-feature tlstm;
case dtls {
reference
"RFC 6353: Transport Layer Security (TLS) Transport Model
for the Simple Network Management Protocol (SNMP).
SNMP-TLS-TM-MIB.snmpDTLSUDPDomain";
container dtls {
uses tls-transport;
}
}
}
}
<CODE ENDS>
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RFC 7407 YANG Data Model for SNMP Configuration December 2014
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
Bjorklund & Schoenwaelder Standards Track [Page 68]
RFC 7407 YANG Data Model for SNMP Configuration December 2014
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 7407; see
the RFC itself for full legal notices.";
reference
"RFC 5592: Secure Shell Transport Model for the
Simple Network Management Protocol (SNMP)";
revision 2014-12-10 {
description
"Initial revision.";
reference
"RFC 7407: 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
"RFC 5592: 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.
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RFC 7407 YANG Data Model for SNMP Configuration December 2014
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
"RFC 5592: Secure Shell Transport Model for the
Simple Network Management Protocol (SNMP).
SNMP-SSH-TM-MIB.snmpSSHDomain";
container ssh {
leaf ip {
type inet:host;
mandatory true;
reference
"RFC 3413: Simple Network Management Protocol (SNMP).
Applications.
SNMP-TARGET-MIB.snmpTargetAddrTAddress
RFC 5592: Secure Shell Transport Model for the
Simple Network Management Protocol (SNMP).
SNMP-SSH-TM-MIB.SnmpSSHAddress";
}
leaf port {
type inet:port-number;
default 5161;
reference
"RFC 3413: Simple Network Management Protocol (SNMP).
Applications.
SNMP-TARGET-MIB.snmpTargetAddrTAddress
RFC 5592: Secure Shell Transport Model for the
Simple Network Management Protocol (SNMP).
SNMP-SSH-TM-MIB.SnmpSSHAddress";
}
leaf username {
type string;
reference
"RFC 3413: Simple Network Management Protocol (SNMP).
Applications.
SNMP-TARGET-MIB.snmpTargetAddrTAddress
RFC 5592: Secure Shell Transport Model for the
Simple Network Management Protocol (SNMP).
SNMP-SSH-TM-MIB.SnmpSSHAddress";
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RFC 7407 YANG Data Model for SNMP Configuration December 2014
}
}
}
}
}
<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 have been 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 7407
name: ietf-x509-cert-to-name
namespace: urn:ietf:params:xml:ns:yang:ietf-x509-cert-to-name
prefix: x509c2n
reference: RFC 7407
The document registers the following YANG submodules in the "YANG
Module Names" registry [RFC6020].
name: ietf-snmp-common
parent: ietf-snmp
reference: RFC 7407
name: ietf-snmp-engine
parent: ietf-snmp
reference: RFC 7407
Bjorklund & Schoenwaelder Standards Track [Page 71]
RFC 7407 YANG Data Model for SNMP Configuration December 2014
name: ietf-snmp-community
parent: ietf-snmp
reference: RFC 7407
name: ietf-snmp-notification
parent: ietf-snmp
reference: RFC 7407
name: ietf-snmp-target
parent: ietf-snmp
reference: RFC 7407
name: ietf-snmp-vacm
parent: ietf-snmp
reference: RFC 7407
name: ietf-snmp-usm
parent: ietf-snmp
reference: RFC 7407
name: ietf-snmp-tsm
parent: ietf-snmp
reference: RFC 7407
name: ietf-snmp-tls
parent: ietf-snmp
reference: RFC 7407
name: ietf-snmp-ssh
parent: ietf-snmp
reference: RFC 7407
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]. The NETCONF access control model
[RFC6536] provides the means to restrict access for particular
NETCONF users to a pre-configured subset of all available NETCONF
protocol operations and content.
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.,
Bjorklund & Schoenwaelder Standards Track [Page 72]
RFC 7407 YANG Data Model for SNMP Configuration December 2014
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:
o The "/snmp/engine" subtree contains the configuration of general
parameters of an SNMP engine such as the endpoints to listen on,
the transports and SNMP versions enabled, or the engine's
identity. Write access to this subtree should only be granted to
entities configuring general SNMP engine parameters.
o The "/snmp/target" subtree contains the configuration of SNMP
targets and, in particular, which transports to use and their
security parameters. Write access to this subtree should only be
granted to the security administrator and entities configuring
SNMP notification forwarding behavior.
o The "/snmp/notify" and "/snmp/notify-filter-profile" subtrees
contain the configuration for the SNMP notification forwarding and
filtering mechanism. Write access to these subtrees should only
be granted to entities configuring SNMP notification forwarding
behavior.
o The "/snmp/proxy" subtree contains the configuration for SNMP
proxies. Write access to this subtree should only be granted to
entities configuring SNMP proxies.
o The "/snmp/community" subtree contains the configuration of the
Community-based Security Model. Write access to this subtree
should only be granted to the security administrator.
o The "/snmp/usm" subtree contains the configuration of the User-
based Security Model. Write access to this subtree should only be
granted to the security administrator.
o The "/snmp/tsm" subtree contains the configuration of the
Transport Layer Security (TLS) Transport Model for SNMP. Write
access to this subtree should only be granted to the security
administrator.
o The "/snmp/tlstm" subtree contains the configuration of the SNMP
transport over (D)TLS and, in particular, the configuration of how
certificates are mapped to SNMP security names. Write access to
this subtree should only be granted to the security administrator.
o The "/snmp/vacm" subtree contains the configuration of the View-
based Access Control Model used by SNMP to authorize access to
management information via SNMP. Write access to this subtree
should only be granted to the security administrator.
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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:
o The "/snmp/engine" subtree exposes general information about an
SNMP engine such as which version(s) of SNMP are enabled or which
transports are enabled.
o The "/snmp/target" subtree exposes information about which
transports are used to reach certain SNMP targets and which
transport-specific parameters are used.
o The "/snmp/notify" and "/snmp/notify-filter-profile" subtrees
expose information about how notifications are filtered and
forwarded to notification targets.
o The "/snmp/proxy" subtree exposes information about proxy
relationships.
o The "/snmp/community", "/snmp/usm", "/snmp/tsm", "/snmp/tlstm",
and "/snmp/vacm" subtrees are specifically sensitive since they
expose information about the authentication and authorization
policy used by an SNMP engine.
Changes to the SNMP access control rules should be done 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 temporarily
open access to resources. Implementations supporting SNMP write
access must ensure that any SNMP access control rule changes over
NETCONF are also atomic 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.
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7. References
7.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997,
<http://www.rfc-editor.org/info/rfc2119>.
[RFC6020] Bjorklund, M., "YANG - A Data Modeling Language for the
Network Configuration Protocol (NETCONF)", RFC 6020,
October 2010, <http://www.rfc-editor.org/info/rfc6020>.
[RFC6241] Enns, R., Bjorklund, M., Schoenwaelder, J., and A.
Bierman, "Network Configuration Protocol (NETCONF)", RFC
6241, June 2011, <http://www.rfc-editor.org/info/rfc6241>.
[RFC6242] Wasserman, M., "Using the NETCONF Protocol over Secure
Shell (SSH)", RFC 6242, June 2011,
<http://www.rfc-editor.org/info/rfc6242>.
[RFC6536] Bierman, A. and M. Bjorklund, "Network Configuration
Protocol (NETCONF) Access Control Model", RFC 6536, March
2012, <http://www.rfc-editor.org/info/rfc6536>.
[RFC6991] Schoenwaelder, J., "Common YANG Data Types", RFC 6991,
July 2013, <http://www.rfc-editor.org/info/rfc6991>.
7.2. 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, <http://www.rfc-editor.org/info/rfc3411>.
[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, <http://www.rfc-editor.org/info/rfc3412>.
[RFC3413] Levi, D., Meyer, P., and B. Stewart, "Simple Network
Management Protocol (SNMP) Applications", STD 62, RFC
3413, December 2002,
<http://www.rfc-editor.org/info/rfc3413>.
[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,
<http://www.rfc-editor.org/info/rfc3414>.
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[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, <http://www.rfc-editor.org/info/rfc3415>.
[RFC3417] Presuhn, R., "Transport Mappings for the Simple Network
Management Protocol (SNMP)", STD 62, RFC 3417, December
2002, <http://www.rfc-editor.org/info/rfc3417>.
[RFC3418] Presuhn, R., "Management Information Base (MIB) for the
Simple Network Management Protocol (SNMP)", STD 62, RFC
3418, December 2002,
<http://www.rfc-editor.org/info/rfc3418>.
[RFC3419] Daniele, M. and J. Schoenwaelder, "Textual Conventions for
Transport Addresses", RFC 3419, December 2002,
<http://www.rfc-editor.org/info/rfc3419>.
[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,
<http://www.rfc-editor.org/info/rfc3584>.
[RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
January 2004, <http://www.rfc-editor.org/info/rfc3688>.
[RFC3826] Blumenthal, U., Maino, F., and K. McCloghrie, "The
Advanced Encryption Standard (AES) Cipher Algorithm in the
SNMP User-based Security Model", RFC 3826, June 2004,
<http://www.rfc-editor.org/info/rfc3826>.
[RFC5591] Harrington, D. and W. Hardaker, "Transport Security Model
for the Simple Network Management Protocol (SNMP)", STD
78, RFC 5591, June 2009,
<http://www.rfc-editor.org/info/rfc5591>.
[RFC5592] Harrington, D., Salowey, J., and W. Hardaker, "Secure
Shell Transport Model for the Simple Network Management
Protocol (SNMP)", RFC 5592, June 2009,
<http://www.rfc-editor.org/info/rfc5592>.
[RFC6353] Hardaker, W., "Transport Layer Security (TLS) Transport
Model for the Simple Network Management Protocol (SNMP)",
STD 78, RFC 6353, July 2011,
<http://www.rfc-editor.org/info/rfc6353>.
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[RFC6643] Schoenwaelder, J., "Translation of Structure of Management
Information Version 2 (SMIv2) MIB Modules to YANG
Modules", RFC 6643, July 2012,
<http://www.rfc-editor.org/info/rfc6643>.
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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>
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<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 configured. 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 conform to
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>
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<user>
<name>russ</name>
<auth>
<sha>
<!--
The 'key' value is split into two lines to conform to
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 conform to
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>
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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"
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>
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</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 an SNMPv1 agent that
recognizes two community strings, "private" and "public", with
different associated read views. The file server is represented as
two "target" instances, one for each community string.
If the proxy receives an 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>
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</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>
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<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>
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</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" 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>
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</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>
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</snmp>
A.7. Transport Layer Security Transport Model Configuration Example
Below is an XML instance document showing the configuration of the
mapping of certificate to security name (see Appendices 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>
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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.
Authors' Addresses
Martin Bjorklund
Tail-f Systems
EMail: mbj@tail-f.com
Juergen Schoenwaelder
Jacobs University
EMail: j.schoenwaelder@jacobs-university.de
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ERRATA
