Network Working Group A. Bierman
Internet-Draft Netconf Central
Intended status: Standards Track M. Bjorklund
Expires: August 3, 2012 Tail-f Systems
January 31, 2012
YANG Data Model for System Management
draft-ietf-netmod-system-mgmt-00
Abstract
This document defines a YANG data model for the configuration and
identification of the management system of a device.
Status of this Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on August 3, 2012.
Copyright Notice
Copyright (c) 2012 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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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3
1.1.1. Terms . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2.1. System Identification . . . . . . . . . . . . . . . . . . 4
2.2. System Time Management . . . . . . . . . . . . . . . . . . 4
2.3. User Authentication . . . . . . . . . . . . . . . . . . . 4
3. System Data Model . . . . . . . . . . . . . . . . . . . . . . 5
3.1. System Identification . . . . . . . . . . . . . . . . . . 5
3.2. System Time Management . . . . . . . . . . . . . . . . . . 5
3.3. DNS Resolver Model . . . . . . . . . . . . . . . . . . . . 5
3.4. RADIUS Client Model . . . . . . . . . . . . . . . . . . . 6
3.5. User Authentication Model . . . . . . . . . . . . . . . . 6
3.5.1. SSH Public Key Authentication . . . . . . . . . . . . 7
3.5.2. Local User Password Authentication . . . . . . . . . . 7
3.5.3. RADIUS Password Authentication . . . . . . . . . . . . 7
3.6. System Control . . . . . . . . . . . . . . . . . . . . . . 8
4. System YANG module . . . . . . . . . . . . . . . . . . . . . . 9
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 35
6. Security Considerations . . . . . . . . . . . . . . . . . . . 36
7. Normative References . . . . . . . . . . . . . . . . . . . . . 38
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 40
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1. Introduction
This document defines a YANG [RFC6020] data model for the
configuration and identification of the management system of a
device.
Devices that are managed by NETCONF and perhaps other mechanisms have
common properties that need to be configured and monitored in a
standard way.
The YANG module defined in this document provides the following
features:
o system administrative data configuration
o system identification monitoring
o system time-of-day configuration and monitoring
o user authentication configuration
o local users configuration
1.1. Terminology
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].
1.1.1. Terms
The following terms are used within this document:
o system: This term refers to the embodiment of the entire set of
management interfaces that a single NETCONF server is supporting
at a given moment. The set of physical entities managed by a
single NETCONF server can be static or it can change dynamically.
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2. Objectives
2.1. System Identification
There are many common properties used to identify devices, operating
systems, software versions, etc. that need to be supported in the
system data module. These objects are defined as operational data
and intended to be specific to the device vendor.
Some user-configurable administrative strings are also provided such
as the system location and description.
2.2. System Time Management
The management of the date and time used by the system need to be
supported. Use of one or more NTP servers to automatically set the
system date and time need to be possible. Utilization of the
Timezone database [I-D.lear-iana-timezone-database] also need to be
supported.
2.3. User Authentication
The authentication mechanism need to support password authentication
over RADIUS, to support deployment scenarios with centralized
authentication servers. Additionally, local users need to be
supported, for scenarios when no centralized authentication server
exists, or for situations where the centralized authentication server
cannot be reached from the device.
Since the mandatory transport protocol for NETCONF is SSH [RFC6242]
the authentication model need to support SSH's "publickey" and
"password" authentication methods [RFC4252].
The model for authentication configuration should be flexible enough
to support authentication methods defined by other standard documents
or by vendors.
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3. System Data Model
3.1. System Identification
The data model for system identification has the following structure:
+--rw system
+--rw contact? string
+--rw name? string
+--rw location? string
+--ro platform
+--ro os-name? string
+--ro os-release? string
+--ro os-version? string
+--ro machine? string
+--ro nodename? string
3.2. System Time Management
The data model for system time management has the following
structure:
+--rw system
+--rw clock
| +--ro current-datetime? yang:date-and-time
| +--ro boot-datetime? yang:date-and-time
| +--rw (timezone)?
| +--:(timezone-location)
| | +--rw timezone-location? string
| +--:(timezone-name)
| | +--rw timezone-name? string
| +--:(timezone-utc-offset)
| +--rw timezone-utc-offset? int16
+--rw ntp
+--rw use-ntp? boolean
+--rw ntp-server [address]
+--rw address inet:host
+--rw enabled boolean
3.3. DNS Resolver Model
The data model for configuration of the DNS resolver has the
following structure:
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+--rw system
+--rw dns
+--rw search* inet:host
+--rw server* inet:ip-address
+--rw options
+--rw ndots? uint8
+--rw timeout? uint8
+--rw attempts? uint8
3.4. RADIUS Client Model
The data model for configuration of the RADIUS client has the
following structure:
+--rw system
+--rw radius
+--rw server [address]
| +--rw address inet:host
| +--rw authentication-port? inet:port-number
| +--rw shared-secret? string
+--rw options
+--rw timeout? uint8
+--rw attempts? uint8
3.5. User Authentication Model
This document defines three authentication methods for use with
NETCONF:
o publickey for local users over SSH
o password for local users over any transport
o password for RADIUS users over any transport
Additional methods can be defined by other standard documents or by
vendors.
This document defines two optional YANG features, "local-users" and
"radius-authentication", which the server advertises to indicate
support for configuring local users on the device, and support for
using RADIUS for authentication, respectively.
The authentication parameters defined in this document are primarily
used to configure authentication of NETCONF users, but MAY also be
used by other interfaces, e.g., a Command Line Interface or a Web-
based User Interface.
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The data model for user authentication has the following structure:
+--rw system
+--rw authentication
+--rw user-authentication-order* identityref
+--rw user [name]
+--rw name string
+--rw password? crypt-hash
+--rw ssh-dsa? binary
+--rw ssh-rsa? binary
3.5.1. SSH Public Key Authentication
If the NETCONF server advertises the "local-users" feature,
configuration of local users and their SSH public keys is supported
in the /system/authentication/user list.
Public key authentication is requested by the SSH client. If the
"local-users" feature is supported, then when a NETCONF client starts
an SSH session towards the server using the "publickey"
authentication "method name" [RFC4252], the SSH server looks up the
user name given in the SSH authentication request in the /system/
authentication/user list, and verifies the key as described in
[RFC4253].
3.5.2. Local User Password Authentication
If the NETCONF server advertises the "local-users" feature,
configuration of local users and their passwords is supported in the
/system/authentication/user list.
For NETCONF transport protocols that support password authentication,
the leaf-list "user-authentication-order" is used to control if local
user password authentication should be used.
In SSH, password authentication is requested by the client. Other
NETCONF transport protocols MAY also support password authentication.
When local user password authentication is requested, the NETCONF
transport looks up the user name provided by the client in the
/system/ authentication/user list, and verifies the password.
3.5.3. RADIUS Password Authentication
If the NETCONF server advertises the "radius-authentication" feature,
the device supports user authentication using RADIUS.
For NETCONF transport protocols that support password authentication,
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the leaf-list "user-authentication-order" is used to control if
RADIUS password authentication should be used.
In SSH, password authentication is requested by the client. Other
NETCONF transport protocols MAY also support password authentication.
3.6. System Control
Two protocol operations are included to restart or shutdown the
system. The 'system-restart' operation can be used to restart the
entire system (not just the NETCONF server). The 'system-shutdown'
operation can be used to power off the entire system.
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4. System YANG module
RFC Ed.: update the date below with the date of RFC publication and
remove this note.
This YANG module imports YANG extensions from
[I-D.ietf-netconf-access-control], imports YANG types from [RFC6021],
and references [RFC1321], [RFC2865], [RFC3418], [RFC5607],
[IEEE-1003.1-2008], and [FIPS.180-3.2008].
<CODE BEGINS> file "ietf-system@2012-01-31.yang"
module ietf-system {
namespace "urn:ietf:params:xml:ns:yang:ietf-system";
prefix "sys";
import ietf-yang-types {
prefix yang;
}
import ietf-inet-types {
prefix inet;
}
import ietf-netconf-acm {
prefix nacm;
}
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: David Kessens
<mailto:david.kessens@nsn.com>
WG Chair: Juergen Schoenwaelder
<mailto:j.schoenwaelder@jacobs-university.de>
Editor: Andy Bierman
<mailto:andy@netconfcentral.org>
Editor: Martin Bjorklund
<mailto:mbj@tail-f.com>";
description
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"This module contains a collection of YANG definitions for the
configuration and identification of the management system of a
device.
Copyright (c) 2011 IETF Trust and the persons identified as
authors of the code. All rights reserved.
Redistribution and use in source and binary forms, with or
without modification, is permitted pursuant to, and subject
to the license terms contained in, the Simplified BSD License
set forth in Section 4.c of the IETF Trust's Legal Provisions
Relating to IETF Documents
(http://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC XXXX; see
the RFC itself for full legal notices.";
// RFC Ed.: replace XXXX with actual RFC number and remove this
// note.
// RFC Ed.: remove this note
// Note: extracted from draft-ietf-netmod-system-mgmt-00.txt
// RFC Ed.: update the date below with the date of RFC publication
// and remove this note.
revision 2012-01-31 {
description
"Initial revision.";
reference
"RFC XXXX: A YANG Data Model for System Management";
}
/*
* Typedefs
*/
typedef timezone-name {
description
"List of available timezone enumerations.
Based on the referenced list, but non-unique names
have been changed so they are unique enumeration
identifiers.";
reference
"Wikipedia: http://en.wikipedia.org/wiki/"
+ "List_of_time_zone_abbreviations";
type enumeration {
enum ACDT {
description
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"Australian Central Daylight Time UTC+10:30";
}
enum ACST {
description
"Australian Central Standard Time UTC+09:30";
}
enum ACT {
description
"ASEAN Common Time UTC+08";
}
enum ADT {
description
"Atlantic Daylight Time UTC-03";
}
enum AEDT {
description
"Australian Eastern Daylight Time UTC+11";
}
enum AEST {
description
"Australian Eastern Standard Time UTC+10";
}
enum AFT {
description
"Afghanistan Time UTC+04:30";
}
enum AKDT {
description
"Alaska Daylight Time UTC-08";
}
enum AKST {
description
"Alaska Standard Time UTC-09";
}
enum AMST {
description
"Armenia Summer Time UTC+05";
}
enum AMT {
description
"Armenia Time UTC+04";
}
enum ART {
description
"Argentina Time UTC-03";
}
enum AST {
description
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"Arab Standard Time (Kuwait, Riyadh) UTC+03";
}
enum AST-2 {
description
"Arabian Standard Time (Abu Dhabi, Muscat) UTC+04";
}
enum AST-3 {
description
"Arabic Standard Time (Baghdad) UTC+03";
}
enum AST-4 {
description
"Atlantic Standard Time UTC-04";
}
enum AWDT {
description
"Australian Western Daylight Time UTC+09";
}
enum AWST {
description
"Australian Western Standard Time UTC+08";
}
enum AZOST {
description
"Azores Standard Time UTC-01";
}
enum AZT {
description
"Azerbaijan Time UTC+04";
}
enum BDT {
description
"Brunei Time UTC+08";
}
enum BIOT {
description
"British Indian Ocean Time UTC+06";
}
enum BIT {
description
"Baker Island Time UTC-12";
}
enum BOT {
description
"Bolivia Time UTC-04";
}
enum BRT {
description
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"Brasilia Time UTC-03";
}
enum BST {
description
"Bangladesh Standard Time UTC+06";
}
enum BST-2 {
description
"British Summer Time (British Standard Time
from Feb 1968 to Oct 1971) UTC+01";
}
enum BTT {
description
"Bhutan Time UTC+06";
}
enum CAT {
description
"Central Africa Time UTC+02";
}
enum CCT {
description
"Cocos Islands Time UTC+06:30";
}
enum CDT {
description
"Central Daylight Time (North America) UTC-05";
}
enum CEDT {
description
"Central European Daylight Time UTC+02";
}
enum CEST {
description
"Central European Summer Time (Cf. HAEC) UTC+02";
}
enum CET {
description
"Central European Time UTC+01";
}
enum CHADT {
description
"Chatham Daylight Time UTC+13:45";
}
enum CHAST {
description
"Chatham Standard Time UTC+12:45";
}
enum CIST {
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description
"Clipperton Island Standard Time UTC-08";
}
enum CKT {
description
"Cook Island Time UTC-10";
}
enum CLST {
description
"Chile Summer Time UTC-03";
}
enum CLT {
description
"Chile Standard Time UTC-04";
}
enum COST {
description
"Colombia Summer Time UTC-04";
}
enum COT {
description
"Colombia Time UTC-05";
}
enum CST {
description
"Central Standard Time (North America) UTC-06";
}
enum CST-2 {
description
"China Standard Time UTC+08";
}
enum CST-3 {
description
"Central Standard Time (Australia) UTC+09:30";
}
enum CT {
description
"China Time UTC+08";
}
enum CVT {
description
"Cape Verde Time UTC-01";
}
enum CXT {
description
"Christmas Island Time UTC+07";
}
enum CHST {
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description
"Chamorro Standard Time UTC+10";
}
enum DFT {
description
"AIX specific equivalent of Central European Time UTC+01";
}
enum EAST {
description
"Easter Island Standard Time UTC-06";
}
enum EAT {
description
"East Africa Time UTC+03";
}
enum ECT {
description
"Eastern Caribbean Time (does not recognise DST) UTC-04";
}
enum ECT-2 {
description
"Ecuador Time UTC-05";
}
enum EDT {
description
"Eastern Daylight Time (North America) UTC-04";
}
enum EEDT {
description
"Eastern European Daylight Time UTC+03";
}
enum EEST {
description
"Eastern European Summer Time UTC+03";
}
enum EET {
description
"Eastern European Time UTC+02";
}
enum EST {
description
"Eastern Standard Time (North America) UTC-05";
}
enum FJT {
description
"Fiji Time UTC+12";
}
enum FKST {
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description
"Falkland Islands Summer Time UTC-03";
}
enum FKT {
description
"Falkland Islands Time UTC-04";
}
enum GALT {
description
"Galapagos Time UTC-06";
}
enum GET {
description
"Georgia Standard Time UTC+04";
}
enum GFT {
description
"French Guiana Time UTC-03";
}
enum GILT {
description
"Gilbert Island Time UTC+12";
}
enum GIT {
description
"Gambier Island Time UTC-09";
}
enum GMT {
description
"Greenwich Mean Time UTC";
}
enum GST {
description
"South Georgia and the South Sandwich Islands UTC-02";
}
enum GST-2 {
description
"Gulf Standard Time UTC+04";
}
enum GYT {
description
"Guyana Time UTC-04";
}
enum HADT {
description
"Hawaii-Aleutian Daylight Time UTC-09";
}
enum HAEC {
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description
"Heure Avancee d'Europe Centrale francised name for
CEST UTC+02";
}
enum HAST {
description
"Hawaii-Aleutian Standard Time UTC-10";
}
enum HKT {
description
"Hong Kong Time UTC+08";
}
enum HMT {
description
"Heard and McDonald Islands Time UTC+05";
}
enum HST {
description
"Hawaii Standard Time UTC-10";
}
enum ICT {
description
"Indochina Time UTC+07";
}
enum IDT {
description
"Israeli Daylight Time UTC+03";
}
enum IRKT {
description
"Irkutsk Time UTC+08";
}
enum IRST {
description
"Iran Standard Time UTC+03:30";
}
enum IST {
description
"Indian Standard Time UTC+05:30";
}
enum IST-2 {
description
"Irish Summer Time UTC+01";
}
enum IST-3 {
description
"Israel Standard Time UTC+02";
}
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enum JST {
description
"Japan Standard Time UTC+09";
}
enum KRAT {
description
"Krasnoyarsk Time UTC+07";
}
enum KST {
description
"Korea Standard Time UTC+09";
}
enum LHST {
description
"Lord Howe Standard Time UTC+10:30";
}
enum LINT {
description
"Line Islands Time UTC+14";
}
enum MAGT {
description
"Magadan Time UTC+11";
}
enum MDT {
description
"Mountain Daylight Time (North America) UTC-06";
}
enum MET {
description
"Middle European Time Same zone as CET UTC+02";
}
enum MEST {
description
"Middle European Saving Time Same zone as CEST UTC+02";
}
enum MIT {
description
"Marquesas Islands Time UTC-09:30";
}
enum MSD {
description
"Moscow Summer Time UTC+04";
}
enum MSK {
description
"Moscow Standard Time UTC+03";
}
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enum MST {
description
"Malaysian Standard Time UTC+08";
}
enum MST-2 {
description
"Mountain Standard Time (North America) UTC-07";
}
enum MST-3 {
description
"Myanmar Standard Time UTC+06:30";
}
enum MUT {
description
"Mauritius Time UTC+04";
}
enum MYT {
description
"Malaysia Time UTC+08";
}
enum NDT {
description
"Newfoundland Daylight Time UTC-02:30";
}
enum NFT {
description
"Norfolk Time[1] UTC+11:30";
}
enum NPT {
description
"Nepal Time UTC+05:45";
}
enum NST {
description
"Newfoundland Standard Time UTC-03:30";
}
enum NT {
description
"Newfoundland Time UTC-03:30";
}
enum NZDT {
description
"New Zealand Daylight Time UTC+13";
}
enum NZST {
description
"New Zealand Standard Time UTC+12";
}
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enum OMST {
description
"Omsk Time UTC+06";
}
enum PDT {
description
"Pacific Daylight Time (North America) UTC-07";
}
enum PETT {
description
"Kamchatka Time UTC+12";
}
enum PHOT {
description
"Phoenix Island Time UTC+13";
}
enum PKT {
description
"Pakistan Standard Time UTC+05";
}
enum PST {
description
"Pacific Standard Time (North America) UTC-08";
}
enum PST-2 {
description
"Philippine Standard Time UTC+08";
}
enum RET {
description
"Reunion Time UTC+04";
}
enum SAMT {
description
"Samara Time UTC+04";
}
enum SAST {
description
"South African Standard Time UTC+02";
}
enum SBT {
description
"Solomon Islands Time UTC+11";
}
enum SCT {
description
"Seychelles Time UTC+04";
}
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enum SGT {
description
"Singapore Time UTC+08";
}
enum SLT {
description
"Sri Lanka Time UTC+05:30";
}
enum SST {
description
"Samoa Standard Time UTC-11";
}
enum SST-2 {
description
"Singapore Standard Time UTC+08";
}
enum TAHT {
description
"Tahiti Time UTC-10";
}
enum THA {
description
"Thailand Standard Time UTC+07";
}
enum UTC {
description
"Coordinated Universal Time UTC";
}
enum UYST {
description
"Uruguay Summer Time UTC-02";
}
enum UYT {
description
"Uruguay Standard Time UTC-03";
}
enum VET {
description
"Venezuelan Standard Time UTC-04:30";
}
enum VLAT {
description
"Vladivostok Time UTC+10";
}
enum WAT {
description
"West Africa Time UTC+01";
}
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enum WEDT {
description
"Western European Daylight Time UTC+01";
}
enum WEST {
description
"Western European Summer Time UTC+01";
}
enum WET {
description
"Western European Time UTC";
}
enum WST {
description
"Western Standard Time UTC+08";
}
enum YAKT {
description
"Yakutsk Time UTC+09";
}
enum YEKT {
description
"Yekaterinburg Time UTC+05";
}
}
}
typedef crypt-hash {
type string {
pattern "$0$.* | $1|5|6$[a-zA-Z0-9./]{2,16}$.*";
}
description
"The crypt-hash type is used to store passwords using
a hash function. This type is implemented in various UNIX
systems as the function crypt(3).
When a clear text value is set to a leaf of this type, the
server calculates a password hash, and stores the result
in the datastore. Thus, the password is never stored in
clear text.
When a leaf of this type is read, the stored password hash is
returned.
A value of this type matches one of the forms:
$0$<clear text password>
$<id>$<salt>$<password hash>
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The '$0$' prefix signals that the value is clear text. When
such a value is received by the server, a hash value is
calculated, and the string '$<id>$<salt>$' is prepended to the
result, where <salt> is a random 2-16 characters long salt
used to generate the digest. This value is stored in the
configuration data store.
If a value starting with '$<id>$<salt>$' is received, the
server knows that the value already represents a hashed value,
and stores it as is in the data store.
When a server needs to verify a password given by a user, it
finds the stored password hash string for that user, extracts
the salt, and calculates the hash with the salt and given
password as input. If the calculated hash value is the same
as the stored value, the password given by the client is
correct.
This type defines the following hash functions:
id | hash function | feature
---+---------------+-------------------
1 | MD5 | crypt-hash-md5
5 | SHA-256 | crypt-hash-sha-256
6 | SHA-512 | crypt-hash-sha-512
The server indicates support for the different hash functions
by advertising the corresponding feature.";
reference
"IEEE Std 1003.1-2008 - crypt() function
Wikipedia: http://en.wikipedia.org/wiki/Crypt_(Unix)
RFC 1321: The MD5 Message-Digest Algorithm
FIPS.180-3.2008: Secure Hash Standard";
}
/*
* Features
*/
feature radius {
description
"Indicates that the device can be configured as a RADIUS
client.";
reference
"RFC 2865: Remote Authentication Dial In User Service "
+ "(RADIUS)";
}
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feature authentication {
description
"Indicates that the device can be configured
to do authentication of users.";
}
feature local-users {
if-feature authentication;
description
"Indicates that the device supports
local user authentication.";
}
feature radius-authentication {
if-feature radius;
if-feature authentication;
description
"Indicates that the device supports user authentication over
RADIUS.";
reference
"RFC 2865: Remote Authentication Dial In User Service (RADIUS)
RFC 5607: Remote Authentication Dial-In User Service (RADIUS)
Authorization for Network Access Server (NAS)
Management";
}
feature crypt-hash-md5 {
description
"Indicates that the device supports the MD5
hash function in 'crypt-hash' values";
reference "RFC 1321: The MD5 Message-Digest Algorithm";
}
feature crypt-hash-sha-256 {
description
"Indicates that the device supports the SHA-256
hash function in 'crypt-hash' values";
reference "FIPS.180-3.2008: Secure Hash Standard";
}
feature crypt-hash-sha-512 {
description
"Indicates that the device supports the SHA-512
hash function in 'crypt-hash' values";
reference "FIPS.180-3.2008: Secure Hash Standard";
}
feature ntp {
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description
"Indicates that the device can be configured
to use one or more NTP servers to set the
system date and time.";
}
feature timezone-location {
description
"Indicates that the local timezone on the device
can be configured to use the TZ database
to set the timezone and manage daylight savings time.";
reference
"TZ Database http://www.twinsun.com/tz/tz-link.htm
Maintaining the Timezone Database
draft-lear-iana-timezone-database-04.txt";
}
feature timezone-name {
description
"Indicates that the local timezone on the device
can be configured using the timezone enumeration
strings as an alias for an UTC offset.";
reference
"Wikipedia: http://en.wikipedia.org/wiki/"
+ "List_of_time_zone_abbreviations";
}
/*
* Identities
*/
identity authentication-method {
description
"Base identity for user authentication methods.";
}
identity radius {
base authentication-method;
description
"Indicates user authentication using RADIUS.";
reference
"RFC 2865: Remote Authentication Dial In User Service (RADIUS)
RFC 5607: Remote Authentication Dial-In User Service (RADIUS)
Authorization for Network Access Server (NAS)
Management";
}
identity local-users {
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base authentication-method;
description
"Indicates password-based authentication of locally
configured users.";
}
/*
* Top-level container
*/
container system {
description
"System group configuration.";
leaf contact {
type string {
length "0..255";
}
default "";
description
"The administrator contact information for the system.";
reference
"RFC 3418 - Management Information Base (MIB) for the
Simple Network Management Protocol (SNMP)
SNMPv2-MIB.sysContact";
}
leaf name {
type string {
length "0..255";
}
default "";
description
"The administratively assigned system name.";
reference
"RFC 3418 - Management Information Base (MIB) for the
Simple Network Management Protocol (SNMP)
SNMPv2-MIB.sysName";
}
leaf location {
type string {
length "0..255";
}
default "";
description
"The system location";
reference
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"RFC 3418 - Management Information Base (MIB) for the
Simple Network Management Protocol (SNMP)
SNMPv2-MIB.sysLocation";
}
container platform {
config false;
description
"Contains vendor-specific information for
identifying the system platform and operating system.";
reference
"IEEE Std 1003.1-2008 - sys/utsname.h";
leaf os-name {
type string;
description
"The name of the operating system in use,
for example 'Linux'";
reference
"IEEE Std 1003.1-2008 - utsname.sysname";
}
leaf os-release {
type string;
description
"The current release level of the operating
system in use. This string MAY indicate
the OS source code revision.";
reference
"IEEE Std 1003.1-2008 - utsname.release";
}
leaf os-version {
type string;
description
"The current version level of the operating
system in use. This string MAY indicate
the specific OS build date and target variant
information.";
reference
"IEEE Std 1003.1-2008 - utsname.version";
}
leaf machine {
type string;
description
"A vendor-specific identifier string representing
the hardware in use.";
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reference
"IEEE Std 1003.1-2008 - utsname.machine";
}
leaf nodename {
type string;
description
"The host name of this system.";
reference
"IEEE Std 1003.1-2008 - utsname.nodename";
}
}
container clock {
description
"Configuration and monitoring of the system
date and time properties.";
leaf current-datetime {
type yang:date-and-time;
config false;
description
"The current system date and time.";
}
leaf boot-datetime {
type yang:date-and-time;
config false;
description
"The system date and time when the NETCONF
server last restarted.";
}
choice timezone {
description
"Configure the system timezone information.";
leaf timezone-location {
if-feature timezone-location;
type string;
description
"The TZ database location identifier string
to use for the system, such as 'Europe/Stockholm'.";
}
leaf timezone-name {
if-feature timezone-name;
type timezone-name;
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description
"The timezone enumeration string to use
for the system, such as 'CET'.";
}
leaf timezone-utc-offset {
type int16 {
range "-1439 .. 1439";
}
description
"The number of minutes to add to UTC time to
identify the timezone for this system.
For example, 'UTC - 8:00 hours' would be
represented as '-480'.";
}
}
}
container ntp {
if-feature ntp;
description
"Configuration of the NTP client.";
leaf use-ntp {
type boolean;
default true;
description
"Indicates that the system should attempt
to synchronize the system clock with an
NTP server from the 'ntp-server' list.";
}
list ntp-server {
key address;
ordered-by user;
description
"List of NTP servers to use for
system clock synchronization. If 'use-ntp'
is 'true', then the system will attempt to
contact and utilize the specified NTP servers.
The user specified order indicates the server priority.";
leaf address {
type inet:host;
description
"The IP address or domain name of the NTP server.";
}
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leaf enabled {
type boolean;
default true;
description
"Indicates whether this server is enabled for use or
not.";
}
}
}
container dns {
description
"Configuration of the DNS resolver.";
leaf-list search {
type inet:host;
ordered-by user;
description
"An ordered list of domains to search when resolving
a host name.";
}
leaf-list server {
type inet:ip-address;
ordered-by user;
description
"Addresses of the name servers that the resolver should
query.
Implementations MAY limit the number of entries in this
leaf list.";
}
container options {
description
"Resolver options. The set of available options has been
limited to those that are generally available across
different resolver implementations, and generally
useful.";
leaf ndots {
type uint8;
default "1";
description
"This parameter sets a threshold for the number of dots
which must appear in a query request before an initial
absolute query will be made.";
}
leaf timeout {
type uint8;
units "seconds";
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default "5";
description
"The amount of time the resolver will wait for a
response from a remote name server before
retrying the query via a different name server.";
}
leaf attempts {
type uint8;
default "2";
description
"The number of times the resolver will send a query to
its name servers before giving up and returning an
error to the calling application.";
}
}
}
container radius {
if-feature radius;
description
"Configuration of the RADIUS client.";
list server {
key address;
ordered-by user;
description
"List of RADIUS servers used by the device.";
leaf address {
type inet:host;
description
"The address of the RADIUS server.";
}
leaf authentication-port {
type inet:port-number;
default "1812";
description
"The port number of the RADIUS server.";
}
leaf shared-secret {
type string;
nacm:default-deny-all;
description
"The shared secret which is known to both the RADIUS
client and server.";
reference
"RFC 2865: Remote Authentication Dial In User Service";
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}
}
container options {
description
"RADIUS client options.";
leaf timeout {
type uint8;
units "seconds";
default "5";
description
"The number of seconds the device will wait for a
response from a RADIUS server before trying with a
different server.";
}
leaf attempts {
type uint8;
default "2";
description
"The number of times the device will send a query to
the RADIUS servers before giving up.";
}
}
}
container authentication {
nacm:default-deny-write;
if-feature authentication;
description
"The authentication configuration subtree.";
leaf-list user-authentication-order {
type identityref {
base authentication-method;
}
must '(. = "sys:radius" and ../../radius/server) or'
+ '(. != "sys:radius")' {
error-message
"When 'radius' is used, a radius server"
+ " must be configured.";
}
ordered-by user;
description
"When the device authenticates a user with
a password, it tries the authentication methods in this
leaf-list in order. If authentication with one method
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fails, the next method is used. If no method succeeds,
the user is denied access.
If the 'radius-authentication' feature is advertised by
the NETCONF server, the 'radius' identity can be added to
this list.
If the 'local-users' feature is advertised by the
NETCONF server, the 'local-users' identity can be
added to this list.";
}
list user {
if-feature local-users;
key name;
description
"The list of local users configured on this device.";
leaf name {
type string;
description
"The user name string identifying this entry.";
}
leaf password {
type crypt-hash;
description
"The password for this entry.";
}
leaf ssh-dsa {
type binary;
description
"The public DSA key for this entry.";
}
leaf ssh-rsa {
type binary;
description
"The public RSA key for this entry.";
}
}
}
}
rpc set-current-datetime {
nacm:default-deny-all;
description
"Manually set the /system/clock/current-datetime leaf
to the specified value.
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If the /system/ntp/ntp-in-use leaf exists and
is set to 'true', then this operation will
fail with error-tag 'operation-failed',
and error-app-tag value of 'ntp-active'";
input {
leaf current-datetime {
type yang:date-and-time;
mandatory true;
description
"The current system date and time.";
}
}
}
rpc system-restart {
nacm:default-deny-all;
description
"Request that the entire system be restarted immediately.
A server SHOULD send an rpc reply to the client before
restarting the system.";
}
rpc system-shutdown {
nacm:default-deny-all;
description
"Request that the entire system be shut down immediately.
A server SHOULD send an rpc reply to the client before
shutting down the system.";
}
}
<CODE ENDS>
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5. IANA Considerations
This document registers a URI in the IETF XML registry [RFC3688].
Following the format in RFC 3688, the following registration is
requested to be made.
URI: urn:ietf:params:xml:ns:yang:ietf-system
Registrant Contact: The NETMOD WG of the IETF.
XML: N/A, the requested URI is an XML namespace.
This document registers a YANG module in the YANG Module Names
registry [RFC6020].
name: ietf-system
namespace: urn:ietf:params:xml:ns:yang:ietf-system
prefix: sys
reference: RFC XXXX
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6. Security Considerations
The YANG module defined in this memo is designed to be accessed via
the NETCONF protocol [RFC6241]. The lowest NETCONF layer is the
secure transport layer and the mandatory-to-implement secure
transport is SSH [RFC6242].
There are a number of data nodes defined in this YANG module which
are writable/creatable/deletable (i.e., config true, which is the
default). These data nodes may be considered sensitive or vulnerable
in some network environments. Write operations (e.g., edit-config)
to these data nodes without proper protection can have a negative
effect on network operations. These are the subtrees and data nodes
and their sensitivity/vulnerability:
o /system/clock/timezone: This choice contains the objects used to
control the timezone used by the device.
o /system/ntp: This container contains the objects used to control
the Network Time Protocol servers used by the device.
o /system/dns: This container contains the objects used to control
the Domain Name System servers used by the device.
o /system/radius: This container contains the objects used to
control the Remote Authentication Dial-In User Service servers
used by the device.
o /system/authentication/user-authentication-order: This leaf
controls how user login attempts are authenticated by the device.
o /system/authentication/user: This list contains the local users
enabled on the system.
Some of the readable data nodes in this YANG module 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 /system/platform: This container has objects which may help
identify the specific NETCONF server and/or operating system
implementation used on the device.
Some of the RPC operations in this YANG module may be considered
sensitive or vulnerable in some network environments. It is thus
important to control access to these operations. These are the
operations and their sensitivity/vulnerability:
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o set-current-datetime: Changes the current date and time on the
device.
o system-restart: Reboots the device.
o system-shutdown: Shuts down the device.
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7. Normative References
[FIPS.180-3.2008]
National Institute of Standards and Technology, "Secure
Hash Standard", FIPS PUB 180-3, October 2008, <http://
csrc.nist.gov/publications/fips/fips180-3/
fips180-3_final.pdf>.
[I-D.ietf-netconf-access-control]
Bierman, A. and M. Bjorklund, "Network Configuration
Protocol (NETCONF) Access Control Model",
draft-ietf-netconf-access-control-05 (work in progress),
October 2011.
[I-D.lear-iana-timezone-database]
Lear, E. and P. Eggert, "IANA Procedures for Maintaining
the Timezone Database",
draft-lear-iana-timezone-database-04 (work in progress),
May 2011.
[IEEE-1003.1-2008]
Institute of Electrical and Electronics Engineers,
"POSIX.1-2008", IEEE Standard 1003.1, March 2008.
[RFC1321] Rivest, R., "The MD5 Message-Digest Algorithm", RFC 1321,
April 1992.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2865] Rigney, C., Willens, S., Rubens, A., and W. Simpson,
"Remote Authentication Dial In User Service (RADIUS)",
RFC 2865, June 2000.
[RFC3418] Presuhn, R., "Management Information Base (MIB) for the
Simple Network Management Protocol (SNMP)", STD 62,
RFC 3418, December 2002.
[RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
January 2004.
[RFC4252] Ylonen, T. and C. Lonvick, "The Secure Shell (SSH)
Authentication Protocol", RFC 4252, January 2006.
[RFC4253] Ylonen, T. and C. Lonvick, "The Secure Shell (SSH)
Transport Layer Protocol", RFC 4253, January 2006.
[RFC5607] Nelson, D. and G. Weber, "Remote Authentication Dial-In
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User Service (RADIUS) Authorization for Network Access
Server (NAS) Management", RFC 5607, July 2009.
[RFC6020] Bjorklund, M., "YANG - A Data Modeling Language for the
Network Configuration Protocol (NETCONF)", RFC 6020,
October 2010.
[RFC6021] Schoenwaelder, J., "Common YANG Data Types", RFC 6021,
October 2010.
[RFC6241] Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed.,
and A. Bierman, Ed., "Network Configuration Protocol
(NETCONF)", RFC 6241, June 2011.
[RFC6242] Wasserman, M., "Using the NETCONF Protocol over Secure
Shell (SSH)", RFC 6242, June 2011.
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Authors' Addresses
Andy Bierman
Netconf Central
Email: andy@netconfcentral.org
Martin Bjorklund
Tail-f Systems
Email: mbj@tail-f.com
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