| NETCONF Working Group | K. Watsen |
| Internet-Draft | Watsen Networks |
| Intended status: Standards Track | March 9, 2019 |
| Expires: September 10, 2019 |
NETCONF Client and Server Models
draft-ietf-netconf-netconf-client-server-09
This document defines two YANG modules, one module to configure a NETCONF client and the other module to configure a NETCONF server. Both modules support both the SSH and TLS transport protocols, and support both standard NETCONF and NETCONF Call Home connections.
This draft contains many placeholder values that need to be replaced with finalized values at the time of publication. This note summarizes all of the substitutions that are needed. No other RFC Editor instructions are specified elsewhere in this document.
This document contains references to other drafts in progress, both in the Normative References section, as well as in body text throughout. Please update the following references to reflect their final RFC assignments:
Artwork in this document contains shorthand references to drafts in progress. Please apply the following replacements:
Artwork in this document contains placeholder values for the date of publication of this draft. Please apply the following replacement:
The following Appendix section is to be removed prior to publication:
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Copyright (c) 2019 IETF Trust and the persons identified as the document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components 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.
This document defines two YANG [RFC7950] modules, one module to configure a NETCONF [RFC6241] client and the other module to configure a NETCONF server. Both modules support both NETCONF over SSH [RFC6242] and NETCONF over TLS [RFC7589] and NETCONF Call Home connections [RFC8071].
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here.
The NETCONF client model presented in this section supports both clients initiating connections to servers, as well as clients listening for connections from servers calling home.
This model supports both the SSH and TLS transport protocols, using the SSH client and TLS client groupings defined in [I-D.ietf-netconf-ssh-client-server] and [I-D.ietf-netconf-tls-client-server] respectively.
All private keys and trusted certificates are held in the keystore model defined in [I-D.ietf-netconf-keystore].
YANG feature statements are used to enable implementations to advertise which parts of the model the NETCONF client supports.
The following tree diagram [RFC8340] provides an overview of the data model for the "ietf-netconf-client" module. Just the container is displayed below, but there is also a reusable grouping called "netconf-client-grouping" that the container is using.
========== NOTE: '\\' line wrapping per BCP XX (RFC XXXX) ===========
module: ietf-netconf-client
+--rw netconf-client
+--rw initiate! {initiate}?
| +--rw netconf-server* [name]
| +--rw name string
| +--rw endpoints
| | +--rw endpoint* [name]
| | +--rw name string
| | +--rw (transport)
| | +--:(ssh) {ssh-initiate}?
| | | +--rw ssh
| | | +--rw remote-address inet:host
| | | +--rw remote-port?
| | | | inet:port-number
| | | +--rw local-address? inet:ip-addr\
\ess
| | | +--rw local-port?
| | | | inet:port-number
| | | +--rw tcp-keepalives {tcp-client-keepalive\
\s}?
| | | | +--rw idle-time? uint16
| | | | +--rw max-probes? uint16
| | | | +--rw probe-interval? uint16
| | | +--rw ssh-client-identity
| | | | +--rw username? string
| | | | +--rw (auth-type)
| | | | +--:(password)
| | | | | +--rw password? string
| | | | +--:(public-key)
| | | | | +--rw public-key
| | | | | +--rw (local-or-keystore)
| | | | | +--:(local)
| | | | | | {local-keys-suppor\
\ted}?
| | | | | | +--rw local-definition
| | | | | | +--rw algorithm?
| | | | | | | asymmetric-ke\
\y-algorithm-ref
| | | | | | +--rw public-key?
| | | | | | | binary
| | | | | | +--rw private-key?
| | | | | | | union
| | | | | | +---x generate-hidden\
\-key
| | | | | | | +---w input
| | | | | | | +---w algorithm
| | | | | | | asymmet\
\ric-key-algorithm-ref
| | | | | | +---x install-hidden-\
\key
| | | | | | +---w input
| | | | | | +---w algorithm
| | | | | | | asymmet\
\ric-key-algorithm-ref
| | | | | | +---w public-ke\
\y?
| | | | | | | binary
| | | | | | +---w private-k\
\ey?
| | | | | | binary
| | | | | +--:(keystore)
| | | | | {keystore-supporte\
\d}?
| | | | | +--rw keystore-reference?
| | | | | ks:asymmetric-ke\
\y-ref
| | | | +--:(certificate)
| | | | +--rw certificate
| | | | {sshcmn:ssh-x509-certs}?
| | | | +--rw (local-or-keystore)
| | | | +--:(local)
| | | | | {local-keys-suppor\
\ted}?
| | | | | +--rw local-definition
| | | | | +--rw algorithm?
| | | | | | asymmetric-ke\
\y-algorithm-ref
| | | | | +--rw public-key?
| | | | | | binary
| | | | | +--rw private-key?
| | | | | | union
| | | | | +---x generate-hidden\
\-key
| | | | | | +---w input
| | | | | | +---w algorithm
| | | | | | asymmet\
\ric-key-algorithm-ref
| | | | | +---x install-hidden-\
\key
| | | | | | +---w input
| | | | | | +---w algorithm
| | | | | | | asymmet\
\ric-key-algorithm-ref
| | | | | | +---w public-ke\
\y?
| | | | | | | binary
| | | | | | +---w private-k\
\ey?
| | | | | | binary
| | | | | +--rw cert?
| | | | | | end-entity-ce\
\rt-cms
| | | | | +---n certificate-exp\
\iration
| | | | | +-- expiration-date
| | | | | yang:date-\
\and-time
| | | | +--:(keystore)
| | | | {keystore-supporte\
\d}?
| | | | +--rw keystore-reference?
| | | | ks:asymmetric-ke\
\y-certificate-ref
| | | +--rw ssh-server-auth
| | | | +--rw pinned-ssh-host-keys?
| | | | | ta:pinned-host-keys-ref
| | | | | {ta:ssh-host-keys}?
| | | | +--rw pinned-ca-certs?
| | | | | ta:pinned-certificates-ref
| | | | | {sshcmn:ssh-x509-certs,ta:x509-\
\certificates}?
| | | | +--rw pinned-server-certs?
| | | | ta:pinned-certificates-ref
| | | | {sshcmn:ssh-x509-certs,ta:x509-\
\certificates}?
| | | +--rw ssh-transport-params
| | | | {ssh-client-transport-params-confi\
\g}?
| | | | +--rw host-key
| | | | | +--rw host-key-alg* identityref
| | | | +--rw key-exchange
| | | | | +--rw key-exchange-alg* identityref
| | | | +--rw encryption
| | | | | +--rw encryption-alg* identityref
| | | | +--rw mac
| | | | +--rw mac-alg* identityref
| | | +--rw ssh-keepalives {ssh-client-keepalive\
\s}?
| | | +--rw max-wait? uint16
| | | +--rw max-attempts? uint8
| | +--:(tls) {tls-initiate}?
| | +--rw tls
| | +--rw remote-address inet:host
| | +--rw remote-port? inet:port-num\
\ber
| | +--rw local-address? inet:ip-addre\
\ss
| | +--rw local-port? inet:port-num\
\ber
| | +--rw tcp-keepalives {tcp-client-keepalive\
\s}?
| | | +--rw idle-time? uint16
| | | +--rw max-probes? uint16
| | | +--rw probe-interval? uint16
| | +--rw tls-client-identity
| | | +--rw (auth-type)
| | | +--:(certificate)
| | | +--rw certificate
| | | +--rw (local-or-keystore)
| | | +--:(local)
| | | | {local-keys-suppor\
\ted}?
| | | | +--rw local-definition
| | | | +--rw algorithm?
| | | | | asymmetric-ke\
\y-algorithm-ref
| | | | +--rw public-key?
| | | | | binary
| | | | +--rw private-key?
| | | | | union
| | | | +---x generate-hidden\
\-key
| | | | | +---w input
| | | | | +---w algorithm
| | | | | asymmet\
\ric-key-algorithm-ref
| | | | +---x install-hidden-\
\key
| | | | | +---w input
| | | | | +---w algorithm
| | | | | | asymmet\
\ric-key-algorithm-ref
| | | | | +---w public-ke\
\y?
| | | | | | binary
| | | | | +---w private-k\
\ey?
| | | | | binary
| | | | +--rw cert?
| | | | | end-entity-ce\
\rt-cms
| | | | +---n certificate-exp\
\iration
| | | | +-- expiration-date
| | | | yang:date-\
\and-time
| | | +--:(keystore)
| | | {keystore-supporte\
\d}?
| | | +--rw keystore-reference?
| | | ks:asymmetric-ke\
\y-certificate-ref
| | +--rw tls-server-auth
| | | +--rw pinned-ca-certs?
| | | | ta:pinned-certificates-ref
| | | | {ta:x509-certificates}?
| | | +--rw pinned-server-certs?
| | | ta:pinned-certificates-ref
| | | {ta:x509-certificates}?
| | +--rw tls-hello-params
| | | {tls-client-hello-params-config}?
| | | +--rw tls-versions
| | | | +--rw tls-version* identityref
| | | +--rw cipher-suites
| | | +--rw cipher-suite* identityref
| | +--rw tls-keepalives {tls-client-keepalive\
\s}?
| | +--rw max-wait? uint16
| | +--rw max-attempts? uint8
| +--rw connection-type
| | +--rw (connection-type)
| | +--:(persistent-connection)
| | | +--rw persistent!
| | +--:(periodic-connection)
| | +--rw periodic!
| | +--rw period? uint16
| | +--rw anchor-time? yang:date-and-time
| | +--rw idle-timeout? uint16
| +--rw reconnect-strategy
| +--rw start-with? enumeration
| +--rw max-attempts? uint8
+--rw listen! {listen}?
+--rw idle-timeout? uint16
+--rw endpoint* [name]
+--rw name string
+--rw (transport)
+--:(ssh) {ssh-listen}?
| +--rw ssh
| +--rw local-address inet:ip-address
| +--rw local-port? inet:port-number
| +--rw tcp-keepalives {tcp-server-keepalives}?
| | +--rw idle-time? uint16
| | +--rw max-probes? uint16
| | +--rw probe-interval? uint16
| +--rw ssh-client-identity
| | +--rw username? string
| | +--rw (auth-type)
| | +--:(password)
| | | +--rw password? string
| | +--:(public-key)
| | | +--rw public-key
| | | +--rw (local-or-keystore)
| | | +--:(local) {local-keys-supported\
\}?
| | | | +--rw local-definition
| | | | +--rw algorithm?
| | | | | asymmetric-key-algo\
\rithm-ref
| | | | +--rw public-key?
| | | | | binary
| | | | +--rw private-key?
| | | | | union
| | | | +---x generate-hidden-key
| | | | | +---w input
| | | | | +---w algorithm
| | | | | asymmetric-ke\
\y-algorithm-ref
| | | | +---x install-hidden-key
| | | | +---w input
| | | | +---w algorithm
| | | | | asymmetric-ke\
\y-algorithm-ref
| | | | +---w public-key?
| | | | | binary
| | | | +---w private-key?
| | | | binary
| | | +--:(keystore) {keystore-supporte\
\d}?
| | | +--rw keystore-reference?
| | | ks:asymmetric-key-ref
| | +--:(certificate)
| | +--rw certificate {sshcmn:ssh-x509-cert\
\s}?
| | +--rw (local-or-keystore)
| | +--:(local) {local-keys-supported\
\}?
| | | +--rw local-definition
| | | +--rw algorithm?
| | | | asymmetric-key-algo\
\rithm-ref
| | | +--rw public-key?
| | | | binary
| | | +--rw private-key?
| | | | union
| | | +---x generate-hidden-key
| | | | +---w input
| | | | +---w algorithm
| | | | asymmetric-ke\
\y-algorithm-ref
| | | +---x install-hidden-key
| | | | +---w input
| | | | +---w algorithm
| | | | | asymmetric-ke\
\y-algorithm-ref
| | | | +---w public-key?
| | | | | binary
| | | | +---w private-key?
| | | | binary
| | | +--rw cert?
| | | | end-entity-cert-cms
| | | +---n certificate-expiration
| | | +-- expiration-date
| | | yang:date-and-ti\
\me
| | +--:(keystore) {keystore-supporte\
\d}?
| | +--rw keystore-reference?
| | ks:asymmetric-key-cert\
\ificate-ref
| +--rw ssh-server-auth
| | +--rw pinned-ssh-host-keys?
| | | ta:pinned-host-keys-ref
| | | {ta:ssh-host-keys}?
| | +--rw pinned-ca-certs?
| | | ta:pinned-certificates-ref
| | | {sshcmn:ssh-x509-certs,ta:x509-certif\
\icates}?
| | +--rw pinned-server-certs?
| | ta:pinned-certificates-ref
| | {sshcmn:ssh-x509-certs,ta:x509-certif\
\icates}?
| +--rw ssh-transport-params
| | {ssh-client-transport-params-config}?
| | +--rw host-key
| | | +--rw host-key-alg* identityref
| | +--rw key-exchange
| | | +--rw key-exchange-alg* identityref
| | +--rw encryption
| | | +--rw encryption-alg* identityref
| | +--rw mac
| | +--rw mac-alg* identityref
| +--rw ssh-keepalives {ssh-client-keepalives}?
| +--rw max-wait? uint16
| +--rw max-attempts? uint8
+--:(tls) {tls-listen}?
+--rw tls
+--rw local-address inet:ip-address
+--rw local-port? inet:port-number
+--rw tcp-keepalives {tcp-server-keepalives}?
| +--rw idle-time? uint16
| +--rw max-probes? uint16
| +--rw probe-interval? uint16
+--rw tls-client-identity
| +--rw (auth-type)
| +--:(certificate)
| +--rw certificate
| +--rw (local-or-keystore)
| +--:(local) {local-keys-supported\
\}?
| | +--rw local-definition
| | +--rw algorithm?
| | | asymmetric-key-algo\
\rithm-ref
| | +--rw public-key?
| | | binary
| | +--rw private-key?
| | | union
| | +---x generate-hidden-key
| | | +---w input
| | | +---w algorithm
| | | asymmetric-ke\
\y-algorithm-ref
| | +---x install-hidden-key
| | | +---w input
| | | +---w algorithm
| | | | asymmetric-ke\
\y-algorithm-ref
| | | +---w public-key?
| | | | binary
| | | +---w private-key?
| | | binary
| | +--rw cert?
| | | end-entity-cert-cms
| | +---n certificate-expiration
| | +-- expiration-date
| | yang:date-and-ti\
\me
| +--:(keystore) {keystore-supporte\
\d}?
| +--rw keystore-reference?
| ks:asymmetric-key-cert\
\ificate-ref
+--rw tls-server-auth
| +--rw pinned-ca-certs?
| | ta:pinned-certificates-ref
| | {ta:x509-certificates}?
| +--rw pinned-server-certs?
| ta:pinned-certificates-ref
| {ta:x509-certificates}?
+--rw tls-hello-params
| {tls-client-hello-params-config}?
| +--rw tls-versions
| | +--rw tls-version* identityref
| +--rw cipher-suites
| +--rw cipher-suite* identityref
+--rw tls-keepalives {tls-client-keepalives}?
+--rw max-wait? uint16
+--rw max-attempts? uint8
The following example illustrates configuring a NETCONF client to initiate connections, using both the SSH and TLS transport protocols, as well as listening for call-home connections, again using both the SSH and TLS transport protocols.
This example is consistent with the examples presented in Section 3.2 of [I-D.ietf-netconf-keystore].
========== NOTE: '\\' line wrapping per BCP XX (RFC XXXX) ===========
<netconf-client
xmlns="urn:ietf:params:xml:ns:yang:ietf-netconf-client">
<!-- NETCONF servers to initiate connections to -->
<initiate>
<netconf-server>
<name>corp-fw1</name>
<endpoints>
<endpoint>
<name>corp-fw1.example.com</name>
<ssh>
<remote-address>corp-fw1.example.com</remote-address>
<tcp-keepalives>
<idle-time>15</idle-time>
<max-probes>3</max-probes>
<probe-interval>30</probe-interval>
</tcp-keepalives>
<ssh-client-identity>
<username>foobar</username>
<public-key>
<local-definition>
<algorithm xmlns:ct="urn:ietf:params:xml:ns:yang:i\
\etf-crypto-types">ct:rsa2048</algorithm>
<private-key>base64encodedvalue==</private-key>
<public-key>base64encodedvalue==</public-key>
</local-definition>
</public-key>
</ssh-client-identity>
<ssh-server-auth>
<pinned-ca-certs>explicitly-trusted-server-ca-certs</p\
\inned-ca-certs>
<pinned-server-certs>explicitly-trusted-server-certs</\
\pinned-server-certs>
</ssh-server-auth>
<ssh-keepalives>
<max-wait>30</max-wait>
<max-attempts>3</max-attempts>
</ssh-keepalives>
</ssh>
</endpoint>
<endpoint>
<name>corp-fw2.example.com</name>
<ssh>
<remote-address>corp-fw2.example.com</remote-address>
<tcp-keepalives>
<idle-time>15</idle-time>
<max-probes>3</max-probes>
<probe-interval>30</probe-interval>
</tcp-keepalives>
<ssh-client-identity>
<username>foobar</username>
<public-key>
<local-definition>
<algorithm xmlns:ct="urn:ietf:params:xml:ns:yang:i\
\etf-crypto-types">ct:rsa2048</algorithm>
<private-key>base64encodedvalue==</private-key>
<public-key>base64encodedvalue==</public-key>
</local-definition>
</public-key>
</ssh-client-identity>
<ssh-server-auth>
<pinned-ca-certs>explicitly-trusted-server-ca-certs</p\
\inned-ca-certs>
<pinned-server-certs>explicitly-trusted-server-certs</\
\pinned-server-certs>
</ssh-server-auth>
<ssh-keepalives>
<max-wait>30</max-wait>
<max-attempts>3</max-attempts>
</ssh-keepalives>
</ssh>
</endpoint>
</endpoints>
<connection-type>
<persistent/>
</connection-type>
<reconnect-strategy>
<start-with>last-connected</start-with>
</reconnect-strategy>
</netconf-server>
</initiate>
<!-- endpoints to listen for NETCONF Call Home connections on -->
<listen>
<endpoint>
<name>Intranet-facing listener</name>
<ssh>
<local-address>192.0.2.7</local-address>
<ssh-client-identity>
<username>foobar</username>
<public-key>
<local-definition>
<algorithm xmlns:ct="urn:ietf:params:xml:ns:yang:ietf-\
\crypto-types">ct:rsa2048</algorithm>
<private-key>base64encodedvalue==</private-key>
<public-key>base64encodedvalue==</public-key>
</local-definition>
</public-key>
</ssh-client-identity>
<ssh-server-auth>
<pinned-ca-certs>explicitly-trusted-server-ca-certs</pinne\
\d-ca-certs>
<pinned-server-certs>explicitly-trusted-server-certs</pinn\
\ed-server-certs>
<pinned-ssh-host-keys>explicitly-trusted-ssh-host-keys</pi\
\nned-ssh-host-keys>
</ssh-server-auth>
</ssh>
</endpoint>
</listen>
</netconf-client>
This YANG module has normative references to [RFC6242], [RFC6991], [RFC7589], [RFC8071], [I-D.kwatsen-netconf-tcp-client-server], [I-D.ietf-netconf-ssh-client-server], and [I-D.ietf-netconf-tls-client-server].
<CODE BEGINS> file "ietf-netconf-client@2019-03-09.yang"
module ietf-netconf-client {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-netconf-client";
prefix "ncc";
import ietf-yang-types {
prefix yang;
reference
"RFC 6991: Common YANG Data Types";
}
import ietf-tcp-client {
prefix tcpc;
reference
"RFC AAAA: YANG Groupings for TCP Clients and TCP Servers";
}
import ietf-tcp-server {
prefix tcps;
reference
"RFC AAAA: YANG Groupings for TCP Clients and TCP Servers";
}
import ietf-ssh-client {
prefix sshc;
revision-date 2019-03-09; // stable grouping definitions
reference
"RFC YYYY: YANG Groupings for SSH Clients and SSH Servers";
}
import ietf-tls-client {
prefix tlsc;
revision-date 2019-03-09; // stable grouping definitions
reference
"RFC ZZZZ: YANG Groupings for TLS Clients and TLS Servers";
}
organization
"IETF NETCONF (Network Configuration) Working Group";
contact
"WG Web: <http://datatracker.ietf.org/wg/netconf/>
WG List: <mailto:netconf@ietf.org>
Author: Kent Watsen <mailto:kent+ietf@watsen.net>
Author: Gary Wu <mailto:garywu@cisco.com>";
description
"This module contains a collection of YANG definitions for
configuring NETCONF clients.
The key words 'MUST', 'MUST NOT', 'REQUIRED', 'SHALL',
'SHALL NOT', 'SHOULD', 'SHOULD NOT', 'RECOMMENDED',
'NOT RECOMMENDED', 'MAY', and 'OPTIONAL' in this document
are to be interpreted as described in BCP 14 [RFC2119]
[RFC8174] when, and only when, they appear in all
capitals, as shown here.
Copyright (c) 2019 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.";
revision "2019-03-09" {
description
"Initial version";
reference
"RFC XXXX: NETCONF Client and Server Models";
}
// Features
feature initiate {
description
"The 'initiate' feature indicates that the NETCONF client
supports initiating NETCONF connections to NETCONF servers
using at least one transport (e.g., SSH, TLS, etc.).";
}
feature ssh-initiate {
description
"The ‘ssh-initiate’ feature indicates that the NETCONF client
supports initiating SSH connections to NETCONF servers.";
reference
"RFC 6242:
Using the NETCONF Protocol over Secure Shell (SSH)";
}
feature tls-initiate {
description
"The ‘tls-initiate’ feature indicates that the NETCONF client
supports initiating TLS connections to NETCONF servers.";
reference
"RFC 7589: Using the NETCONF Protocol over Transport
Layer Security (TLS) with Mutual X.509
Authentication";
}
feature listen {
description
"The 'listen' feature indicates that the NETCONF client
supports opening a port to accept NETCONF server call
home connections using at least one transport (e.g.,
SSH, TLS, etc.).";
}
feature ssh-listen {
description
"The ‘ssh-listen’ feature indicates that the NETCONF client
supports opening a port to listen for incoming NETCONF
server call-home SSH connections.";
reference
"RFC 8071: NETCONF Call Home and RESTCONF Call Home";
}
feature tls-listen {
description
"The ‘tls-listen’ feature indicates that the NETCONF client
supports opening a port to listen for incoming NETCONF
server call-home TLS connections.";
reference
"RFC 8071: NETCONF Call Home and RESTCONF Call Home";
}
// Groupings
grouping netconf-client-grouping {
description
"Top-level grouping for NETCONF client configuration.";
container initiate {
if-feature initiate;
presence "Enables client to initiate TCP connections";
description
"Configures client initiating underlying TCP connections.";
list netconf-server {
key name;
min-elements 1;
description
"List of NETCONF servers the NETCONF client is to
initiate connections to in parallel.";
leaf name {
type string;
description
"An arbitrary name for the NETCONF server.";
}
container endpoints {
description
"Container for the list of endpoints.";
list endpoint {
key name;
min-elements 1;
ordered-by user;
description
"A user-ordered list of endpoints that the NETCONF
client will attempt to connect to in the specified
sequence. Defining more than one enables
high-availability.";
leaf name {
type string;
description
"An arbitrary name for the endpoint.";
}
choice transport {
mandatory true;
description
"Selects between available transports.";
case ssh {
if-feature ssh-initiate;
container ssh {
description
"Specifies IP and SSH specific configuration
for the connection.";
uses tcpc:tcp-client-grouping {
refine "remote-port" {
default 830;
description
"The NETCONF client will attempt to connect
to the IANA-assigned well-known port value
for 'netconf-ssh' (443) if no value is
specified.";
}
}
uses sshc:ssh-client-grouping;
} // container ssh
} // case ssh
case tls {
if-feature tls-initiate;
container tls {
description
"Specifies IP and TLS specific configuration
for the connection.";
uses tcpc:tcp-client-grouping {
refine "remote-port" {
default 6513;
description
"The NETCONF client will attempt to connect
to the IANA-assigned well-known port value
for 'netconf-tls' (6513) if no value is
specified.";
}
}
uses tlsc:tls-client-grouping {
refine "tls-client-identity/auth-type" {
mandatory true;
description
"NETCONF/TLS clients MUST pass some
authentication credentials.";
}
}
} // container tls
} // case tls
} // choice transport
} // list endpoint
} // container endpoints
container connection-type {
description
"Indicates the NETCONF client's preference for how the
NETCONF connection is maintained.";
choice connection-type {
mandatory true;
description
"Selects between available connection types.";
case persistent-connection {
container persistent {
presence
"Indicates that a persistent connection is to be
maintained.";
description
"Maintain a persistent connection to the NETCONF
server. If the connection goes down, immediately
start trying to reconnect to it, using the
reconnection strategy.
This connection type minimizes any NETCONF server
to NETCONF client data-transfer delay, albeit at
the expense of holding resources longer.";
}
}
case periodic-connection {
container periodic {
presence
"Indicates that a periodic connection is to be
maintained.";
description
"Periodically connect to the NETCONF server. The
NETCONF server should close the connection upon
completing planned activities.
This connection type increases resource
utilization, albeit with increased delay in
NETCONF server to NETCONF client interactions.";
leaf period {
type uint16;
units "minutes";
default 60;
description
"Duration of time between periodic connections.";
}
leaf anchor-time {
type yang:date-and-time {
// constrained to minute-level granularity
pattern '\d{4}-\d{2}-\d{2}T\d{2}:\d{2}'
+ '(Z|[\+\-]\d{2}:\d{2})';
}
description
"Designates a timestamp before or after which a
series of periodic connections are determined.
The periodic connections occur at a whole
multiple interval from the anchor time. For
example, for an anchor time is 15 minutes past
midnight and a period interval of 24 hours, then
a periodic connection will occur 15 minutes past
midnight everyday.";
}
leaf idle-timeout {
type uint16;
units "seconds";
default 120; // two minutes
description
"Specifies the maximum number of seconds that
a NETCONF session may remain idle. A NETCONF
session will be dropped if it is idle for an
interval longer than this number of seconds.
If set to zero, then the NETCONF client will
never drop a session because it is idle.";
}
}
}
}
}
container reconnect-strategy {
description
"The reconnection strategy directs how a NETCONF client
reconnects to a NETCONF server, after discovering its
connection to the server has dropped, even if due to a
reboot. The NETCONF client starts with the specified
endpoint and tries to connect to it max-attempts times
before trying the next endpoint in the list (round
robin).";
leaf start-with {
type enumeration {
enum first-listed {
description
"Indicates that reconnections should start with
the first endpoint listed.";
}
enum last-connected {
description
"Indicates that reconnections should start with
the endpoint last connected to. If no previous
connection has ever been established, then the
first endpoint configured is used. NETCONF
clients SHOULD be able to remember the last
endpoint connected to across reboots.";
}
enum random-selection {
description
"Indicates that reconnections should start with
a random endpoint.";
}
}
default first-listed;
description
"Specifies which of the NETCONF server's endpoints
the NETCONF client should start with when trying
to connect to the NETCONF server.";
}
leaf max-attempts {
type uint8 {
range "1..max";
}
default 3;
description
"Specifies the number times the NETCONF client tries
to connect to a specific endpoint before moving on
to the next endpoint in the list (round robin).";
}
}
} // netconf-server
} // initiate
container listen {
if-feature listen;
presence "Enables client to accept call-home connections";
description
"Configures client accepting call-home TCP connections.";
leaf idle-timeout {
type uint16;
units "seconds";
default 3600; // one hour
description
"Specifies the maximum number of seconds that a NETCONF
session may remain idle. A NETCONF session will be
dropped if it is idle for an interval longer than this
number of seconds. If set to zero, then the server
will never drop a session because it is idle. Sessions
that have a notification subscription active are never
dropped.";
}
list endpoint {
key name;
min-elements 1;
description
"List of endpoints to listen for NETCONF connections.";
leaf name {
type string;
description
"An arbitrary name for the NETCONF listen endpoint.";
}
choice transport {
mandatory true;
description
"Selects between available transports.";
case ssh {
if-feature ssh-listen;
container ssh {
description
"SSH-specific listening configuration for inbound
connections.";
uses tcps:tcp-server-grouping {
refine "local-port" {
default 4334;
description
"The NETCONF client will listen on the IANA-
assigned well-known port for 'netconf-ch-ssh'
(4334) if no value is specified.";
}
}
uses sshc:ssh-client-grouping;
}
}
case tls {
if-feature tls-listen;
container tls {
description
"TLS-specific listening configuration for inbound
connections.";
uses tcps:tcp-server-grouping {
refine "local-port" {
default 4334;
description
"The NETCONF client will listen on the IANA-
assigned well-known port for 'netconf-ch-ssh'
(4334) if no value is specified.";
}
}
uses tlsc:tls-client-grouping {
refine "tls-client-identity/auth-type" {
mandatory true;
description
"NETCONF/TLS clients MUST pass some
authentication credentials.";
}
}
}
}
} // transport
} // endpoint
} // listen
} // netconf-client
// Protocol accessible node, for servers that 'implement'
// this module.
container netconf-client {
uses netconf-client-grouping;
description
"Top-level container for NETCONF client configuration.";
}
}
<CODE ENDS>
The NETCONF server model presented in this section supports servers both listening for connections as well as initiating call-home connections.
This model supports both the SSH and TLS transport protocols, using the SSH server and TLS server groupings defined in [I-D.ietf-netconf-ssh-client-server] and [I-D.ietf-netconf-tls-client-server] respectively.
All private keys and trusted certificates are held in the keystore model defined in [I-D.ietf-netconf-keystore].
YANG feature statements are used to enable implementations to advertise which parts of the model the NETCONF server supports.
The following tree diagram [RFC8340] provides an overview of the data model for the "ietf-netconf-server" module. Just the container is displayed below, but there is also a reusable grouping called "netconf-server-grouping" that the container is using.
========== NOTE: '\\' line wrapping per BCP XX (RFC XXXX) ===========
module: ietf-netconf-server
+--rw netconf-server
+--rw listen! {listen}?
| +--rw idle-timeout? uint16
| +--rw endpoint* [name]
| +--rw name string
| +--rw (transport)
| +--:(ssh) {ssh-listen}?
| | +--rw ssh
| | +--rw local-address inet:ip-address
| | +--rw local-port? inet:port-number
| | +--rw tcp-keepalives {tcp-server-keepalives}?
| | | +--rw idle-time? uint16
| | | +--rw max-probes? uint16
| | | +--rw probe-interval? uint16
| | +--rw ssh-server-identity
| | | +--rw host-key* [name]
| | | +--rw name string
| | | +--rw (host-key-type)
| | | +--:(public-key)
| | | | +--rw public-key
| | | | +--rw (local-or-keystore)
| | | | +--:(local)
| | | | | {local-keys-supported\
\}?
| | | | | +--rw local-definition
| | | | | +--rw algorithm?
| | | | | | asymmetric-key-a\
\lgorithm-ref
| | | | | +--rw public-key?
| | | | | | binary
| | | | | +--rw private-key?
| | | | | | union
| | | | | +---x generate-hidden-key
| | | | | | +---w input
| | | | | | +---w algorithm
| | | | | | asymmetric\
\-key-algorithm-ref
| | | | | +---x install-hidden-key
| | | | | +---w input
| | | | | +---w algorithm
| | | | | | asymmetric\
\-key-algorithm-ref
| | | | | +---w public-key?
| | | | | | binary
| | | | | +---w private-key?
| | | | | binary
| | | | +--:(keystore)
| | | | {keystore-supported}?
| | | | +--rw keystore-reference?
| | | | ks:asymmetric-key-r\
\ef
| | | +--:(certificate)
| | | +--rw certificate
| | | {sshcmn:ssh-x509-certs}?
| | | +--rw (local-or-keystore)
| | | +--:(local)
| | | | {local-keys-supported\
\}?
| | | | +--rw local-definition
| | | | +--rw algorithm?
| | | | | asymmetric-key-a\
\lgorithm-ref
| | | | +--rw public-key?
| | | | | binary
| | | | +--rw private-key?
| | | | | union
| | | | +---x generate-hidden-key
| | | | | +---w input
| | | | | +---w algorithm
| | | | | asymmetric\
\-key-algorithm-ref
| | | | +---x install-hidden-key
| | | | | +---w input
| | | | | +---w algorithm
| | | | | | asymmetric\
\-key-algorithm-ref
| | | | | +---w public-key?
| | | | | | binary
| | | | | +---w private-key?
| | | | | binary
| | | | +--rw cert?
| | | | | end-entity-cert-\
\cms
| | | | +---n certificate-expira\
\tion
| | | | +-- expiration-date
| | | | yang:date-and\
\-time
| | | +--:(keystore)
| | | {keystore-supported}?
| | | +--rw keystore-reference?
| | | ks:asymmetric-key-c\
\ertificate-ref
| | +--rw ssh-client-cert-auth {sshcmn:ssh-x509-cert\
\s}?
| | | +--rw pinned-ca-certs?
| | | | ta:pinned-certificates-ref
| | | | {ta:x509-certificates}?
| | | +--rw pinned-client-certs?
| | | ta:pinned-certificates-ref
| | | {ta:x509-certificates}?
| | +--rw ssh-transport-params
| | | {ssh-server-transport-params-config}?
| | | +--rw host-key
| | | | +--rw host-key-alg* identityref
| | | +--rw key-exchange
| | | | +--rw key-exchange-alg* identityref
| | | +--rw encryption
| | | | +--rw encryption-alg* identityref
| | | +--rw mac
| | | +--rw mac-alg* identityref
| | +--rw ssh-keepalives {ssh-server-keepalives}?
| | +--rw max-wait? uint16
| | +--rw max-attempts? uint8
| +--:(tls) {tls-listen}?
| +--rw tls
| +--rw local-address inet:ip-address
| +--rw local-port? inet:port-number
| +--rw tcp-keepalives {tcp-server-keepalives}?
| | +--rw idle-time? uint16
| | +--rw max-probes? uint16
| | +--rw probe-interval? uint16
| +--rw tls-server-identity
| | +--rw (local-or-keystore)
| | +--:(local) {local-keys-supported}?
| | | +--rw local-definition
| | | +--rw algorithm?
| | | | asymmetric-key-algorithm-ref
| | | +--rw public-key? bina\
\ry
| | | +--rw private-key? union
| | | +---x generate-hidden-key
| | | | +---w input
| | | | +---w algorithm
| | | | asymmetric-key-algorit\
\hm-ref
| | | +---x install-hidden-key
| | | | +---w input
| | | | +---w algorithm
| | | | | asymmetric-key-algorit\
\hm-ref
| | | | +---w public-key? binary
| | | | +---w private-key? binary
| | | +--rw cert?
| | | | end-entity-cert-cms
| | | +---n certificate-expiration
| | | +-- expiration-date
| | | yang:date-and-time
| | +--:(keystore) {keystore-supported}?
| | +--rw keystore-reference?
| | ks:asymmetric-key-certificate-r\
\ef
| +--rw tls-client-auth
| | +--rw pinned-ca-certs?
| | | ta:pinned-certificates-ref
| | | {ta:x509-certificates}?
| | +--rw pinned-client-certs?
| | | ta:pinned-certificates-ref
| | | {ta:x509-certificates}?
| | +--rw cert-maps
| | +--rw cert-to-name* [id]
| | +--rw id uint32
| | +--rw fingerprint
| | | x509c2n:tls-fingerprint
| | +--rw map-type identityref
| | +--rw name string
| +--rw tls-hello-params
| | {tls-server-hello-params-config}?
| | +--rw tls-versions
| | | +--rw tls-version* identityref
| | +--rw cipher-suites
| | +--rw cipher-suite* identityref
| +--rw tls-keepalives {tls-server-keepalives}?
| +--rw max-wait? uint16
| +--rw max-attempts? uint8
+--rw call-home! {call-home}?
+--rw netconf-client* [name]
+--rw name string
+--rw endpoints
| +--rw endpoint* [name]
| +--rw name string
| +--rw (transport)
| +--:(ssh) {ssh-call-home}?
| | +--rw ssh
| | +--rw remote-address inet:host
| | +--rw remote-port?
| | | inet:port-number
| | +--rw local-address? inet:ip-addr\
\ess
| | +--rw local-port?
| | | inet:port-number
| | +--rw tcp-keepalives {tcp-client-keepalive\
\s}?
| | | +--rw idle-time? uint16
| | | +--rw max-probes? uint16
| | | +--rw probe-interval? uint16
| | +--rw ssh-server-identity
| | | +--rw host-key* [name]
| | | +--rw name string
| | | +--rw (host-key-type)
| | | +--:(public-key)
| | | | +--rw public-key
| | | | +--rw (local-or-keystore)
| | | | +--:(local)
| | | | | {local-keys-sup\
\ported}?
| | | | | +--rw local-definition
| | | | | +--rw algorithm?
| | | | | | asymmetric\
\-key-algorithm-ref
| | | | | +--rw public-key?
| | | | | | binary
| | | | | +--rw private-key?
| | | | | | union
| | | | | +---x generate-hid\
\den-key
| | | | | | +---w input
| | | | | | +---w algori\
\thm
| | | | | | asym\
\metric-key-algorithm-ref
| | | | | +---x install-hidd\
\en-key
| | | | | +---w input
| | | | | +---w algori\
\thm
| | | | | | asym\
\metric-key-algorithm-ref
| | | | | +---w public\
\-key?
| | | | | | bina\
\ry
| | | | | +---w privat\
\e-key?
| | | | | bina\
\ry
| | | | +--:(keystore)
| | | | {keystore-suppo\
\rted}?
| | | | +--rw keystore-refere\
\nce?
| | | | ks:asymmetric\
\-key-ref
| | | +--:(certificate)
| | | +--rw certificate
| | | {sshcmn:ssh-x509-certs\
\}?
| | | +--rw (local-or-keystore)
| | | +--:(local)
| | | | {local-keys-sup\
\ported}?
| | | | +--rw local-definition
| | | | +--rw algorithm?
| | | | | asymmetric\
\-key-algorithm-ref
| | | | +--rw public-key?
| | | | | binary
| | | | +--rw private-key?
| | | | | union
| | | | +---x generate-hid\
\den-key
| | | | | +---w input
| | | | | +---w algori\
\thm
| | | | | asym\
\metric-key-algorithm-ref
| | | | +---x install-hidd\
\en-key
| | | | | +---w input
| | | | | +---w algori\
\thm
| | | | | | asym\
\metric-key-algorithm-ref
| | | | | +---w public\
\-key?
| | | | | | bina\
\ry
| | | | | +---w privat\
\e-key?
| | | | | bina\
\ry
| | | | +--rw cert?
| | | | | end-entity\
\-cert-cms
| | | | +---n certificate-\
\expiration
| | | | +-- expiration-\
\date
| | | | yang:da\
\te-and-time
| | | +--:(keystore)
| | | {keystore-suppo\
\rted}?
| | | +--rw keystore-refere\
\nce?
| | | ks:asymmetric\
\-key-certificate-ref
| | +--rw ssh-client-cert-auth
| | | {sshcmn:ssh-x509-certs}?
| | | +--rw pinned-ca-certs?
| | | | ta:pinned-certificates-ref
| | | | {ta:x509-certificates}?
| | | +--rw pinned-client-certs?
| | | ta:pinned-certificates-ref
| | | {ta:x509-certificates}?
| | +--rw ssh-transport-params
| | | {ssh-server-transport-params-confi\
\g}?
| | | +--rw host-key
| | | | +--rw host-key-alg* identityref
| | | +--rw key-exchange
| | | | +--rw key-exchange-alg* identityref
| | | +--rw encryption
| | | | +--rw encryption-alg* identityref
| | | +--rw mac
| | | +--rw mac-alg* identityref
| | +--rw ssh-keepalives {ssh-server-keepalive\
\s}?
| | +--rw max-wait? uint16
| | +--rw max-attempts? uint8
| +--:(tls) {tls-call-home}?
| +--rw tls
| +--rw remote-address inet:host
| +--rw remote-port? inet:port-num\
\ber
| +--rw local-address? inet:ip-addre\
\ss
| +--rw local-port? inet:port-num\
\ber
| +--rw tcp-keepalives {tcp-client-keepalive\
\s}?
| | +--rw idle-time? uint16
| | +--rw max-probes? uint16
| | +--rw probe-interval? uint16
| +--rw tls-server-identity
| | +--rw (local-or-keystore)
| | +--:(local) {local-keys-supported}?
| | | +--rw local-definition
| | | +--rw algorithm?
| | | | asymmetric-key-algorit\
\hm-ref
| | | +--rw public-key?
| | | | binary
| | | +--rw private-key?
| | | | union
| | | +---x generate-hidden-key
| | | | +---w input
| | | | +---w algorithm
| | | | asymmetric-key-a\
\lgorithm-ref
| | | +---x install-hidden-key
| | | | +---w input
| | | | +---w algorithm
| | | | | asymmetric-key-a\
\lgorithm-ref
| | | | +---w public-key? bin\
\ary
| | | | +---w private-key? bin\
\ary
| | | +--rw cert?
| | | | end-entity-cert-cms
| | | +---n certificate-expiration
| | | +-- expiration-date
| | | yang:date-and-time
| | +--:(keystore) {keystore-supported}?
| | +--rw keystore-reference?
| | ks:asymmetric-key-certifi\
\cate-ref
| +--rw tls-client-auth
| | +--rw pinned-ca-certs?
| | | ta:pinned-certificates-ref
| | | {ta:x509-certificates}?
| | +--rw pinned-client-certs?
| | | ta:pinned-certificates-ref
| | | {ta:x509-certificates}?
| | +--rw cert-maps
| | +--rw cert-to-name* [id]
| | +--rw id uint32
| | +--rw fingerprint
| | | x509c2n:tls-fingerprint
| | +--rw map-type identityref
| | +--rw name string
| +--rw tls-hello-params
| | {tls-server-hello-params-config}?
| | +--rw tls-versions
| | | +--rw tls-version* identityref
| | +--rw cipher-suites
| | +--rw cipher-suite* identityref
| +--rw tls-keepalives {tls-server-keepalive\
\s}?
| +--rw max-wait? uint16
| +--rw max-attempts? uint8
+--rw connection-type
| +--rw (connection-type)
| +--:(persistent-connection)
| | +--rw persistent!
| +--:(periodic-connection)
| +--rw periodic!
| +--rw period? uint16
| +--rw anchor-time? yang:date-and-time
| +--rw idle-timeout? uint16
+--rw reconnect-strategy
+--rw start-with? enumeration
+--rw max-attempts? uint8
The following example illustrates configuring a NETCONF server to listen for NETCONF client connections using both the SSH and TLS transport protocols, as well as configuring call-home to two NETCONF clients, one using SSH and the other using TLS.
This example is consistent with the examples presented in Section 3.2 of [I-D.ietf-netconf-keystore].
========== NOTE: '\\' line wrapping per BCP XX (RFC XXXX) ===========
<netconf-server
xmlns="urn:ietf:params:xml:ns:yang:ietf-netconf-server"
xmlns:x509c2n="urn:ietf:params:xml:ns:yang:ietf-x509-cert-to-name">
<!-- endpoints to listen for NETCONF connections on -->
<listen>
<endpoint> <!-- listening for SSH connections -->
<name>netconf/ssh</name>
<ssh>
<local-address>192.0.2.7</local-address>
<ssh-server-identity>
<host-key>
<name>deployment-specific-certificate</name>
<public-key>
<local-definition>
<algorithm xmlns:ct="urn:ietf:params:xml:ns:yang:iet\
\f-crypto-types">ct:rsa2048</algorithm>
<private-key>base64encodedvalue==</private-key>
<public-key>base64encodedvalue==</public-key>
</local-definition>
</public-key>
</host-key>
</ssh-server-identity>
<ssh-client-cert-auth>
<pinned-ca-certs>explicitly-trusted-client-ca-certs</pinne\
\d-ca-certs>
<pinned-client-certs>explicitly-trusted-client-certs</pinn\
\ed-client-certs>
</ssh-client-cert-auth>
</ssh>
</endpoint>
<endpoint> <!-- listening for TLS sessions -->
<name>netconf/tls</name>
<tls>
<local-address>192.0.2.7</local-address>
<tls-server-identity>
<local-definition>
<algorithm xmlns:ct="urn:ietf:params:xml:ns:yang:ietf-cr\
\ypto-types">ct:rsa2048</algorithm>
<private-key>base64encodedvalue==</private-key>
<public-key>base64encodedvalue==</public-key>
<cert>base64encodedvalue==</cert>
</local-definition>
</tls-server-identity>
<tls-client-auth>
<pinned-ca-certs>explicitly-trusted-client-ca-certs</pinne\
\d-ca-certs>
<pinned-client-certs>explicitly-trusted-client-certs</pinn\
\ed-client-certs>
<cert-maps>
<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>B3:4F:A1:8C:54</fingerprint>
<map-type>x509c2n:specified</map-type>
<name>scooby-doo</name>
</cert-to-name>
</cert-maps>
</tls-client-auth>
</tls>
</endpoint>
</listen>
<!-- calling home to SSH and TLS based NETCONF clients -->
<call-home>
<netconf-client> <!-- SSH-based client -->
<name>config-mgr</name>
<endpoints>
<endpoint>
<name>east-data-center</name>
<ssh>
<remote-address>east.config-mgr.example.com</remote-addr\
\ess>
<ssh-server-identity>
<host-key>
<name>deployment-specific-certificate</name>
<public-key>
<local-definition>
<algorithm xmlns:ct="urn:ietf:params:xml:ns:yang\
\:ietf-crypto-types">ct:rsa2048</algorithm>
<private-key>base64encodedvalue==</private-key>
<public-key>base64encodedvalue==</public-key>
</local-definition>
</public-key>
</host-key>
</ssh-server-identity>
<ssh-client-cert-auth>
<pinned-ca-certs>explicitly-trusted-client-ca-certs</p\
\inned-ca-certs>
<pinned-client-certs>explicitly-trusted-client-certs</\
\pinned-client-certs>
</ssh-client-cert-auth>
</ssh>
</endpoint>
<endpoint>
<name>west-data-center</name>
<ssh>
<remote-address>west.config-mgr.example.com</remote-addr\
\ess>
<ssh-server-identity>
<host-key>
<name>deployment-specific-certificate</name>
<public-key>
<local-definition>
<algorithm xmlns:ct="urn:ietf:params:xml:ns:yang\
\:ietf-crypto-types">ct:rsa2048</algorithm>
<private-key>base64encodedvalue==</private-key>
<public-key>base64encodedvalue==</public-key>
</local-definition>
</public-key>
</host-key>
</ssh-server-identity>
<ssh-client-cert-auth>
<pinned-ca-certs>explicitly-trusted-client-ca-certs</p\
\inned-ca-certs>
<pinned-client-certs>explicitly-trusted-client-certs</\
\pinned-client-certs>
</ssh-client-cert-auth>
</ssh>
</endpoint>
</endpoints>
<connection-type>
<periodic>
<idle-timeout>300</idle-timeout>
<period>60</period>
</periodic>
</connection-type>
<reconnect-strategy>
<start-with>last-connected</start-with>
<max-attempts>3</max-attempts>
</reconnect-strategy>
</netconf-client>
<netconf-client> <!-- TLS-based client -->
<name>data-collector</name>
<endpoints>
<endpoint>
<name>east-data-center</name>
<tls>
<remote-address>east.analytics.example.com</remote-addre\
\ss>
<tls-server-identity>
<local-definition>
<algorithm xmlns:ct="urn:ietf:params:xml:ns:yang:iet\
\f-crypto-types">ct:rsa2048</algorithm>
<private-key>base64encodedvalue==</private-key>
<public-key>base64encodedvalue==</public-key>
<cert>base64encodedvalue==</cert>
</local-definition>
</tls-server-identity>
<tls-client-auth>
<pinned-ca-certs>explicitly-trusted-client-ca-certs</p\
\inned-ca-certs>
<pinned-client-certs>explicitly-trusted-client-certs</\
\pinned-client-certs>
<cert-maps>
<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>B3:4F:A1:8C:54</fingerprint>
<map-type>x509c2n:specified</map-type>
<name>scooby-doo</name>
</cert-to-name>
</cert-maps>
</tls-client-auth>
<tcp-keepalives>
<idle-time>15</idle-time>
<max-probes>3</max-probes>
<probe-interval>30</probe-interval>
</tcp-keepalives>
<tls-keepalives>
<max-wait>30</max-wait>
<max-attempts>3</max-attempts>
</tls-keepalives>
</tls>
</endpoint>
<endpoint>
<name>west-data-center</name>
<tls>
<remote-address>west.analytics.example.com</remote-addre\
\ss>
<tls-server-identity>
<local-definition>
<algorithm xmlns:ct="urn:ietf:params:xml:ns:yang:iet\
\f-crypto-types">ct:rsa2048</algorithm>
<private-key>base64encodedvalue==</private-key>
<public-key>base64encodedvalue==</public-key>
<cert>base64encodedvalue==</cert>
</local-definition>
</tls-server-identity>
<tls-client-auth>
<pinned-ca-certs>explicitly-trusted-client-ca-certs</p\
\inned-ca-certs>
<pinned-client-certs>explicitly-trusted-client-certs</\
\pinned-client-certs>
<cert-maps>
<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>B3:4F:A1:8C:54</fingerprint>
<map-type>x509c2n:specified</map-type>
<name>scooby-doo</name>
</cert-to-name>
</cert-maps>
</tls-client-auth>
<tcp-keepalives>
<idle-time>15</idle-time>
<max-probes>3</max-probes>
<probe-interval>30</probe-interval>
</tcp-keepalives>
<tls-keepalives>
<max-wait>30</max-wait>
<max-attempts>3</max-attempts>
</tls-keepalives>
</tls>
</endpoint>
</endpoints>
<connection-type>
<persistent/>
</connection-type>
<reconnect-strategy>
<start-with>first-listed</start-with>
<max-attempts>3</max-attempts>
</reconnect-strategy>
</netconf-client>
</call-home>
</netconf-server>
This YANG module has normative references to [RFC6242], [RFC6991], [RFC7407], [RFC7589], [RFC8071], [I-D.kwatsen-netconf-tcp-client-server], [I-D.ietf-netconf-ssh-client-server], and [I-D.ietf-netconf-tls-client-server].
This YANG module imports YANG types from [RFC6991], and YANG groupings from [RFC7407], [I-D.ietf-netconf-ssh-client-server] and [I-D.ietf-netconf-ssh-client-server].
<CODE BEGINS> file "ietf-netconf-server@2019-03-09.yang"
module ietf-netconf-server {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-netconf-server";
prefix "ncs";
import ietf-yang-types {
prefix yang;
reference
"RFC 6991: Common YANG Data Types";
}
import ietf-x509-cert-to-name {
prefix x509c2n;
reference
"RFC 7407: A YANG Data Model for SNMP Configuration";
}
import ietf-tcp-client {
prefix tcpc;
reference
"RFC AAAA: YANG Groupings for TCP Clients and TCP Servers";
}
import ietf-tcp-server {
prefix tcps;
reference
"RFC AAAA: YANG Groupings for TCP Clients and TCP Servers";
}
import ietf-ssh-server {
prefix sshs;
revision-date 2019-03-09; // stable grouping definitions
reference
"RFC YYYY: YANG Groupings for SSH Clients and SSH Servers";
}
import ietf-tls-server {
prefix tlss;
revision-date 2019-03-09; // stable grouping definitions
reference
"RFC ZZZZ: YANG Groupings for TLS Clients and TLS Servers";
}
organization
"IETF NETCONF (Network Configuration) Working Group";
contact
"WG Web: <http://datatracker.ietf.org/wg/netconf/>
WG List: <mailto:netconf@ietf.org>
Author: Kent Watsen <mailto:kent+ietf@watsen.net>
Author: Gary Wu <mailto:garywu@cisco.com>
Author: Juergen Schoenwaelder
<mailto:j.schoenwaelder@jacobs-university.de>";
description
"This module contains a collection of YANG definitions for
configuring NETCONF servers.
The key words 'MUST', 'MUST NOT', 'REQUIRED', 'SHALL',
'SHALL NOT', 'SHOULD', 'SHOULD NOT', 'RECOMMENDED',
'NOT RECOMMENDED', 'MAY', and 'OPTIONAL' in this document
are to be interpreted as described in BCP 14 [RFC2119]
[RFC8174] when, and only when, they appear in all
capitals, as shown here.
Copyright (c) 2019 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.";
revision "2019-03-09" {
description
"Initial version";
reference
"RFC XXXX: NETCONF Client and Server Models";
}
// Features
feature listen {
description
"The 'listen' feature indicates that the NETCONF server
supports opening a port to accept NETCONF client connections
using at least one transport (e.g., SSH, TLS, etc.).";
}
feature ssh-listen {
description
"The 'ssh-listen' feature indicates that the NETCONF server
supports opening a port to accept NETCONF over SSH
client connections.";
reference
"RFC 6242:
Using the NETCONF Protocol over Secure Shell (SSH)";
}
feature tls-listen {
description
"The 'tls-listen' feature indicates that the NETCONF server
supports opening a port to accept NETCONF over TLS
client connections.";
reference
"RFC 7589: Using the NETCONF Protocol over Transport
Layer Security (TLS) with Mutual X.509
Authentication";
}
feature call-home {
description
"The 'call-home' feature indicates that the NETCONF server
supports initiating NETCONF call home connections to
NETCONF clients using at least one transport (e.g., SSH,
TLS, etc.).";
reference
"RFC 8071: NETCONF Call Home and RESTCONF Call Home";
}
feature ssh-call-home {
description
"The 'ssh-call-home' feature indicates that the NETCONF
server supports initiating a NETCONF over SSH call
home connection to NETCONF clients.";
reference
"RFC 8071: NETCONF Call Home and RESTCONF Call Home";
}
feature tls-call-home {
description
"The 'tls-call-home' feature indicates that the NETCONF
server supports initiating a NETCONF over TLS call
home connection to NETCONF clients.";
reference
"RFC 8071: NETCONF Call Home and RESTCONF Call Home";
}
// Groupings
grouping netconf-server-grouping {
description
"Top-level grouping for NETCONF server configuration.";
container listen {
if-feature listen;
presence "Enables server to listen for TCP connections";
description "Configures listen behavior";
leaf idle-timeout {
type uint16;
units "seconds";
default 3600; // one hour
description
"Specifies the maximum number of seconds that a NETCONF
session may remain idle. A NETCONF session will be
dropped if it is idle for an interval longer than this
number of seconds. If set to zero, then the server
will never drop a session because it is idle. Sessions
that have a notification subscription active are never
dropped.";
}
list endpoint {
key name;
min-elements 1;
description
"List of endpoints to listen for NETCONF connections.";
leaf name {
type string;
description
"An arbitrary name for the NETCONF listen endpoint.";
}
choice transport {
mandatory true;
description
"Selects between available transports.";
case ssh {
if-feature ssh-listen;
container ssh {
description
"SSH-specific listening configuration for inbound
connections.";
uses tcps:tcp-server-grouping {
refine "local-port" {
default 830;
description
"The NETCONF server will listen on the IANA-
assigned well-known port value for 'netconf-ssh'
(830) if no value is specified.";
}
}
uses sshs:ssh-server-grouping;
}
}
case tls {
if-feature tls-listen;
container tls {
description
"TLS-specific listening configuration for inbound
connections.";
uses tcps:tcp-server-grouping {
refine "local-port" {
default 6513;
description
"The NETCONF server will listen on the IANA-
assigned well-known port value for 'netconf-tls'
(6513) if no value is specified.";
}
}
uses tlss:tls-server-grouping {
refine "tls-client-auth" {
must 'pinned-ca-certs or pinned-client-certs';
description
"NETCONF/TLS servers MUST validate client
certiticates.";
}
augment "tls-client-auth" {
description
"Augments in the cert-to-name structure.";
container cert-maps {
uses x509c2n:cert-to-name;
description
"The cert-maps container is used by a TLS-
based NETCONF server to map the NETCONF
client's presented X.509 certificate to a
NETCONF username. If no matching and valid
cert-to-name list entry can be found, then
the NETCONF server MUST close the connection,
and MUST NOT accept NETCONF messages over
it.";
reference
"RFC WWWW: NETCONF over TLS, Section 7";
}
}
}
}
}
}
}
}
container call-home {
if-feature call-home;
presence "Enables server to initiate TCP connections";
description "Configures call-home behavior";
list netconf-client {
key name;
min-elements 1;
description
"List of NETCONF clients the NETCONF server is to
initiate call-home connections to in parallel.";
leaf name {
type string;
description
"An arbitrary name for the remote NETCONF client.";
}
container endpoints {
description
"Container for the list of endpoints.";
list endpoint {
key name;
min-elements 1;
ordered-by user;
description
"A non-empty user-ordered list of endpoints for this
NETCONF server to try to connect to in sequence.
Defining more than one enables high-availability.";
leaf name {
type string;
description
"An arbitrary name for this endpoint.";
}
choice transport {
mandatory true;
description
"Selects between available transports.";
case ssh {
if-feature ssh-call-home;
container ssh {
description
"Specifies SSH-specific call-home transport
configuration.";
uses tcpc:tcp-client-grouping {
refine "remote-port" {
default 4334;
description
"The NETCONF server will attempt to connect
to the IANA-assigned well-known port for
'netconf-ch-tls' (4334) if no value is
specified.";
}
}
uses sshs:ssh-server-grouping;
}
}
case tls {
if-feature tls-call-home;
container tls {
description
"Specifies TLS-specific call-home transport
configuration.";
uses tcpc:tcp-client-grouping {
refine "remote-port" {
default 4335;
description
"The NETCONF server will attempt to connect
to the IANA-assigned well-known port for
'netconf-ch-tls' (4335) if no value is
specified.";
}
}
uses tlss:tls-server-grouping {
refine "tls-client-auth" {
must 'pinned-ca-certs or pinned-client-certs';
description
"NETCONF/TLS servers MUST validate client
certiticates.";
}
augment "tls-client-auth" {
description
"Augments in the cert-to-name structure.";
container cert-maps {
uses x509c2n:cert-to-name;
description
"The cert-maps container is used by a
TLS-based NETCONF server to map the
NETCONF client's presented X.509
certificate to a NETCONF username. If
no matching and valid cert-to-name list
entry can be found, then the NETCONF
server MUST close the connection, and
MUST NOT accept NETCONF messages over
it.";
reference
"RFC WWWW: NETCONF over TLS, Section 7";
}
}
}
}
} // tls
} // choice
} // endpoint
} // endpoints
container connection-type {
description
"Indicates the NETCONF server's preference for how the
NETCONF connection is maintained.";
choice connection-type {
mandatory true;
description
"Selects between available connection types.";
case persistent-connection {
container persistent {
presence
"Indicates that a persistent connection is to be
maintained.";
description
"Maintain a persistent connection to the NETCONF
client. If the connection goes down, immediately
start trying to reconnect to it, using the
reconnection strategy.
This connection type minimizes any NETCONF client
to NETCONF server data-transfer delay, albeit at
the expense of holding resources longer.";
} // container persistent
} // case persistent-connection
case periodic-connection {
container periodic {
presence
"Indicates that a periodic connection is to be
maintained.";
description
"Periodically connect to the NETCONF client. The
NETCONF client should close the underlying TLS
connection upon completing planned activities.
This connection type increases resource
utilization, albeit with increased delay in
NETCONF client to NETCONF client interactions.";
leaf period {
type uint16;
units "minutes";
default 60;
description
"Duration of time between periodic connections.";
}
leaf anchor-time {
type yang:date-and-time {
// constrained to minute-level granularity
pattern '\d{4}-\d{2}-\d{2}T\d{2}:\d{2}'
+ '(Z|[\+\-]\d{2}:\d{2})';
}
description
"Designates a timestamp before or after which a
series of periodic connections are determined.
The periodic connections occur at a whole
multiple interval from the anchor time. For
example, for an anchor time is 15 minutes past
midnight and a period interval of 24 hours, then
a periodic connection will occur 15 minutes past
midnight everyday.";
}
leaf idle-timeout {
type uint16;
units "seconds";
default 120; // two minutes
description
"Specifies the maximum number of seconds that
a NETCONF session may remain idle. A NETCONF
session will be dropped if it is idle for an
interval longer than this number of seconds.
If set to zero, then the server will never
drop a session because it is idle.";
}
} // container periodic
} // case periodic-connection
} // choice connection-type
} // container connection-type
container reconnect-strategy {
description
"The reconnection strategy directs how a NETCONF server
reconnects to a NETCONF client, after discovering its
connection to the client has dropped, even if due to a
reboot. The NETCONF server starts with the specified
endpoint and tries to connect to it max-attempts times
before trying the next endpoint in the list (round
robin).";
leaf start-with {
type enumeration {
enum first-listed {
description
"Indicates that reconnections should start with
the first endpoint listed.";
}
enum last-connected {
description
"Indicates that reconnections should start with
the endpoint last connected to. If no previous
connection has ever been established, then the
first endpoint configured is used. NETCONF
servers SHOULD be able to remember the last
endpoint connected to across reboots.";
}
enum random-selection {
description
"Indicates that reconnections should start with
a random endpoint.";
}
}
default first-listed;
description
"Specifies which of the NETCONF client's endpoints
the NETCONF server should start with when trying
to connect to the NETCONF client.";
}
leaf max-attempts {
type uint8 {
range "1..max";
}
default 3;
description
"Specifies the number times the NETCONF server tries
to connect to a specific endpoint before moving on
to the next endpoint in the list (round robin).";
}
} // container reconnect-strategy
} // list netconf-client
} // container call-home
} // grouping netconf-server-grouping
// Protocol accessible node, for servers that *implement*
// this module.
container netconf-server {
uses netconf-server-grouping;
description
"Top-level container for NETCONF server configuration.";
}
}
<CODE ENDS>
Editorial: this section is a hold over from before, previously called "Objectives". It was only written two support the "server" (not the "client"). The question is if it's better to add the missing "client" parts, or remove this section altogether.
The primary purpose of the YANG modules defined herein is to enable the configuration of the NETCONF client and servers. This scope includes the following objectives:
The YANG module should support all current NETCONF transports, namely NETCONF over SSH [RFC6242], NETCONF over TLS [RFC7589], and to be extensible to support future transports as necessary.
Because implementations may not support all transports, the modules should use YANG "feature" statements so that implementations can accurately advertise which transports are supported.
Servers may have a multiplicity of host-keys or server-certificates from which subsets may be selected for specific uses. For instance, a NETCONF server may want to use one set of SSH host-keys when listening on port 830, and a different set of SSH host-keys when calling home. The data models provided herein should enable configuration of which keys to use on a per-use basis.
When a certificate is used to authenticate a NETCONF client, there is a need to configure the server to know how to authenticate the certificates. The server should be able to authenticate the client's certificate either by using path-validation to a configured trust anchor or by matching the client-certificate to one previously configured.
When a client certificate is used for TLS client authentication, the NETCONF server must be able to derive a username from the authenticated certificate. Thus the modules defined herein should enable this mapping to be configured.
The NETCONF protocols were originally defined as having the server opening a port to listen for client connections. More recently the NETCONF working group defined support for call-home ([RFC8071]), enabling the server to initiate the connection to the client. Thus the modules defined herein should enable configuration for both listening for connections and calling home. Because implementations may not support both listening for connections and calling home, YANG "feature" statements should be used so that implementation can accurately advertise the connection types it supports.
The following objectives only pertain to call home connections.
A NETCONF server may be managed by more than one NETCONF client. For instance, a deployment may have one client for provisioning and another for fault monitoring. Therefore, when it is desired for a server to initiate call home connections, it should be able to do so to more than one client.
A NETCONF client managing a NETCONF server may implement a high-availability strategy employing a multiplicity of active and/or passive endpoint. Therefore, when it is desired for a server to initiate call home connections, it should be able to connect to any of the client's endpoints.
Assuming a NETCONF client has more than one endpoint, then it becomes necessary to configure how a NETCONF server should reconnect to the client should it lose its connection to one the client's endpoints. For instance, the NETCONF server may start with first endpoint defined in a user-ordered list of endpoints or with the last endpoints it was connected to.
NETCONF clients may vary greatly on how frequently they need to interact with a NETCONF server, how responsive interactions need to be, and how many simultaneous connections they can support. Some clients may need a persistent connection to servers to optimize real-time interactions, while others prefer periodic interactions in order to minimize resource requirements. Therefore, when it is necessary for server to initiate connections, it should be configurable if the connection is persistent or periodic.
The reconnection strategy should apply to both persistent and periodic connections. How it applies to periodic connections becomes clear when considering that a periodic "connection" is a logical connection to a single server. That is, the periods of unconnectedness are intentional as opposed to due to external reasons. A periodic "connection" should always reconnect to the same server until it is no longer able to, at which time the reconnection strategy guides how to connect to another server.
If a persistent connection is desired, it is the responsibility of the connection initiator to actively test the "aliveness" of the connection. The connection initiator must immediately work to reestablish a persistent connection as soon as the connection is lost. How often the connection should be tested is driven by NETCONF client requirements, and therefore keep-alive settings should be configurable on a per-client basis.
If a periodic connection is desired, it is necessary for the NETCONF server to know how often it should connect. This frequency determines the maximum amount of time a NETCONF client may have to wait to send data to a server. A server may connect to a client before this interval expires if desired (e.g., to send data to a client).
The YANG module defined in this document uses groupings defined in [I-D.ietf-netconf-ssh-client-server] and [I-D.ietf-netconf-tls-client-server]. Please see the Security Considerations section in those documents for concerns related those groupings.
The YANG module defined in this document is designed to be accessed via YANG based management protocols, such as NETCONF [RFC6241] and RESTCONF [RFC8040]. Both of these protocols have mandatory-to-implement secure transport layers (e.g., SSH, TLS) with mutual authentication.
The NETCONF access control model (NACM) [RFC8341] provides the means to restrict access for particular users to a pre-configured subset of all available protocol operations and content.
There are a number of data nodes defined in this YANG module that are writable/creatable/deletable (i.e., config true, which is the default). These data nodes may be considered sensitive or vulnerable in some network environments. Write operations (e.g., edit-config) to these data nodes without proper protection can have a negative effect on network operations. These are the subtrees and data nodes and their sensitivity/vulnerability:
Some of the readable data nodes in 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:
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:
This document registers two URIs in the "ns" subregistry of the IETF XML Registry [RFC3688]. Following the format in [RFC3688], the following registrations are requested:
URI: urn:ietf:params:xml:ns:yang:ietf-netconf-client Registrant Contact: The NETCONF WG of the IETF. XML: N/A, the requested URI is an XML namespace. URI: urn:ietf:params:xml:ns:yang:ietf-netconf-server Registrant Contact: The NETCONF WG of the IETF. XML: N/A, the requested URI is an XML namespace.
This document registers two YANG modules in the YANG Module Names registry [RFC6020]. Following the format in [RFC6020], the the following registrations are requested:
name: ietf-netconf-client namespace: urn:ietf:params:xml:ns:yang:ietf-netconf-client prefix: ncc reference: RFC XXXX name: ietf-netconf-server namespace: urn:ietf:params:xml:ns:yang:ietf-netconf-server prefix: ncs reference: RFC XXXX
| [I-D.ietf-netconf-keystore] | Watsen, K., "YANG Data Model for a Centralized Keystore Mechanism", Internet-Draft draft-ietf-netconf-keystore-07, October 2018. |
| [I-D.ietf-netconf-ssh-client-server] | Watsen, K., Wu, G. and L. Xia, "YANG Groupings for SSH Clients and SSH Servers", Internet-Draft draft-ietf-netconf-ssh-client-server-08, October 2018. |
| [I-D.ietf-netconf-tls-client-server] | Watsen, K., Wu, G. and L. Xia, "YANG Groupings for TLS Clients and TLS Servers", Internet-Draft draft-ietf-netconf-tls-client-server-08, October 2018. |
| [I-D.kwatsen-netconf-tcp-client-server] | Watsen, K., "YANG Groupings for TCP Clients and TCP Servers", Internet-Draft draft-kwatsen-netconf-tcp-client-server-00, March 2019. |
| [RFC2119] | Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997. |
| [RFC6020] | Bjorklund, M., "YANG - A Data Modeling Language for the Network Configuration Protocol (NETCONF)", RFC 6020, DOI 10.17487/RFC6020, October 2010. |
| [RFC6241] | Enns, R., Bjorklund, M., Schoenwaelder, J. and A. Bierman, "Network Configuration Protocol (NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011. |
| [RFC6242] | Wasserman, M., "Using the NETCONF Protocol over Secure Shell (SSH)", RFC 6242, DOI 10.17487/RFC6242, June 2011. |
| [RFC6991] | Schoenwaelder, J., "Common YANG Data Types", RFC 6991, DOI 10.17487/RFC6991, July 2013. |
| [RFC7407] | Bjorklund, M. and J. Schoenwaelder, "A YANG Data Model for SNMP Configuration", RFC 7407, DOI 10.17487/RFC7407, December 2014. |
| [RFC7589] | Badra, M., Luchuk, A. and J. Schoenwaelder, "Using the NETCONF Protocol over Transport Layer Security (TLS) with Mutual X.509 Authentication", RFC 7589, DOI 10.17487/RFC7589, June 2015. |
| [RFC7950] | Bjorklund, M., "The YANG 1.1 Data Modeling Language", RFC 7950, DOI 10.17487/RFC7950, August 2016. |
| [RFC8174] | Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, May 2017. |
| [RFC3688] | Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688, DOI 10.17487/RFC3688, January 2004. |
| [RFC8040] | Bierman, A., Bjorklund, M. and K. Watsen, "RESTCONF Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017. |
| [RFC8071] | Watsen, K., "NETCONF Call Home and RESTCONF Call Home", RFC 8071, DOI 10.17487/RFC8071, February 2017. |
| [RFC8340] | Bjorklund, M. and L. Berger, "YANG Tree Diagrams", BCP 215, RFC 8340, DOI 10.17487/RFC8340, March 2018. |
| [RFC8341] | Bierman, A. and M. Bjorklund, "Network Configuration Access Control Model", STD 91, RFC 8341, DOI 10.17487/RFC8341, March 2018. |
The authors would like to thank for following for lively discussions on list and in the halls (ordered by last name): Andy Bierman, Martin Bjorklund, Benoit Claise, Ramkumar Dhanapal, Mehmet Ersue, Balázs Kovács, David Lamparter, Alan Luchuk, Ladislav Lhotka, Radek Krejci, Tom Petch, Juergen Schoenwaelder, Phil Shafer, Sean Turner, and Bert Wijnen.