NETCONF Working Group K. Watsen Internet-Draft Juniper Networks Intended status: Standards Track J. Schoenwaelder Expires:March 26,April 29, 2015 Jacobs University BremenSeptember 22,October 26, 2014 NETCONF Server Configuration Modeldraft-ietf-netconf-server-model-03draft-ietf-netconf-server-model-04 Abstract This draft defines a NETCONF server configuration data model. This data model enables configuration of the NETCONF service itself, including which transports it supports, what ports they listen on, whetherthey support device-initiated connections,call-home is supported, and associated parameters. 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 onMarch 26,April 29, 2015. Copyright Notice Copyright (c) 2014 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . .23 1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3 1.2. Tree Diagrams . . . . . . . . . . . . . . . . . . . . . . 3 2. Objectives . . . . . . . . . . . . . . . . . . . . . . . . . 3 2.1. Support all NETCONFTransportstransports . . . . . . . . . . . . . 3 2.2.Align Transport-Specific ConfigurationsEnable each transport to select which keys to use . . . . 4 2.3. Support authenticating client-certificates . . . . . . .3 2.3.4 2.4. Support mapping authenticated client-certificates to usernames . . . . . . . . . . . . . . . . . . . . . . . . 4 2.5. Support both Listening forConnectionsconnections and Call Home . . 42.4.2.6. For Call HomeConnectionsconnections . . . . . . . . . . . . . . . . 42.4.1.2.6.1. SupportMoremore thanOne Applicationone application . . . . . . . . . . 42.4.2.2.6.2. SupportApplications Having Moreapplications having more thanOne Serverone server . .4 2.4.3.5 2.6.3. Support aReconnection Strategyreconnection strategy . . . . . . . . . . .4 2.4.4.5 2.6.4. Support bothPersistentpersistent andPeriodic Connectionsperiodic connections . .4 2.4.5.5 2.6.5. ReconnectionStrategystrategy forPeriodic Connectionsperiodic connections . . . 52.4.6. Keep-Alives2.6.6. Keep-alives forPersistent Connectionspersistent connections . . . . . . . 52.4.7.2.6.7. Customizations forPeriodic Connectionsperiodic connections . . . . . . .56 3. Data Model . . . . . . . . . . . . . . . . . . . . . . . . . 6 3.1. Overview . . . . . . . . . . . . . . . . . . . . . . . . 63.2. YANG Module3.1.1. The "session-options" subtree . . . . . . . . . . . . 6 3.1.2. The "listen" subtree . . . . . . . . . . .8 4. Keep-Alives for SSH and TLS. . . . . 6 3.1.3. The "call-home" subtree . . . . . . . . . . . .21 4.1. SSH. . . 7 3.1.4. The "ssh" subtree . . . . . . . . . . . . . . . . . . 9 3.1.5. The "tls" subtree . . . . . . . . . . .21 4.2. TLS. . . . . . . 9 3.2. YANG Module . . . . . . . . . . . . . . . . . . . . . . . 10 4. Implementation strategy for keep-alives . . . . . . . . . . . 24 4.1. Keep-alives for SSH . . . . . . . . . . . . . . . . . . . 24 4.2. Keep-alives for TLS . . . . . . . . . . . . . . . . . . .2225 5. Security Considerations . . . . . . . . . . . . . . . . . . .2225 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . .2326 7. Other Considerations . . . . . . . . . . . . . . . . . . . .2326 8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . .2326 9. References . . . . . . . . . . . . . . . . . . . . . . . . .2427 9.1. Normative References . . . . . . . . . . . . . . . . . .2427 9.2. Informative References . . . . . . . . . . . . . . . . .2528 Appendix A. Examples . . . . . . . . . . . . . . . . . . . . . .2629 A.1. SSH Transport Configuration + State . . . . . . . . . . .. . . . 2629 A.2. TLS Transport Configuration + State . . . . . . . . . . .. . . . 2631 Appendix B. Change Log . . . . . . . . . . . . . . . . . . . . .2732 B.1. 00 to 01 . . . . . . . . . . . . . . . . . . . . . . . .2833 B.2. 01 to 02 . . . . . . . . . . . . . . . . . . . . . . . .2833 B.3. 02 to 03 . . . . . . . . . . . . . . . . . . . . . . . .2833 B.4. 03 to 04 . . . . . . . . . . . . . . . . . . . . . . . . 33 Appendix C. Open Issues . . . . . . . . . . . . . . . . . . . .2834 1. Introduction This draft defines a NETCONF [RFC6241] server configuration data model. This data model enables configuration of the NETCONF service itself, including which transports are supported, what portsdoesthe serverlistenlistens on, whether call-home is supported, and associated parameters. 1.1. Terminology The keywords "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in RFC 2119 [RFC2119]. 1.2. Tree Diagrams A simplified graphical representation of data models is used in this document. The meaning of the symbols in these diagrams is as follows: o Brackets "[" and "]" enclose list keys. o Abbreviations before data node names: "rw" means configuration (read-write) and "ro" state data (read-only). o Symbols after data node names: "?" means an optional node, "!" means a presence container, and "*" denotes a list and leaf-list. o Parentheses enclose choice and case nodes, and case nodes are also marked with a colon (":"). 2. Objectives The primary purpose of the YANG module defined herein is to enable the configuration of the NETCONF server service on the device. This scope includes the following objectives: 2.1. Support all NETCONFTransportstransports The YANG module should support all current NETCONF transports, namely NETCONF over SSH [RFC6242] and NETCONF over TLS [rfc5539bis], and be extensible to support future transports as necessary.SinceBecause implementations may not support all transports, the module should use YANG "feature" statements so that implementations can accurately advertise which transports are supported. 2.2.Align Transport-Specific Configurations WhileEnable each transportis unique in its protocol andto select which keys to use Systems may havesome distinct configurations,a multiplicity of host-keys or server-certificates from which subsets are configured for specific uses. For instance, a system 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. 2.3. Support authenticating client-certificates When certificates are used to authenticate NETCONF clients, thereremainsis asignificant overlap between them. Thusneed to configure theYANG module should use "grouping" statements so thatsystem to know how to authenticate thecommon aspects cancertificates. The system should be able to do this either by using path-validation to a configuredsimilarly. 2.3.trust anchor or by matching the client-certificate to one previously configured. 2.4. Support mapping authenticated client-certificates to usernames Some transports (e.g., TLS) need additional support to map authenticated transport-level sessions to a NETCONF username. The NETCONF server model defined herein should define an ability for this mapping to be configured." 2.5. Support both Listening forConnectionsconnections and Call Home NETCONF has always supported the server opening a port to listen for client connections. More recently the NETCONF working group defined support for call-home ([draft-ietf-netconf-call-home]). The module should configure both listening for connections and call-home.SinceBecause implementations may not support both listening for connections and call home, YANG "feature" statements should be used so that implementation can accurately advertise the connection types it supports.2.4.2.6. For Call HomeConnectionsconnections The following objectives only pertain to call home connections.2.4.1.2.6.1. SupportMoremore thanOne Applicationone application A device may be managed by more than one northbound application. For instance, a deployment may have one application for provisioning and another for fault monitoring. Therefore, when it is desired for a device to initiate call home connections, it should be able to do so for more than one application.2.4.2.2.6.2. SupportApplications Having Moreapplications having more thanOne Serverone server An application managing a device may implement a high-availability strategy employing a multiplicity of active and/or passive servers. Therefore, when it is desired for a device to initiate call home connections, it should be able to connect to any of theapplicationsapplication's servers.2.4.3.2.6.3. Support aReconnection Strategyreconnection strategy Assuming an application has more than one server, then it becomes necessary to configure how a device should reconnect to the application should it lose its connection to the application's servers. Of primary interest is if the device should start with first server defined in a user-ordered list of servers or with the last server it was connected to. Secondary settings might specify the frequency of attempts and number of attempts per server. Therefore, a reconnection strategy should be configurable.2.4.4.2.6.4. Support bothPersistentpersistent andPeriodic Connectionsperiodic connections Applications may vary greatly on how frequently they need to interact with a device, how responsive interactions with devices need to be, and how many simultaneous connections they can support. Some applications may need a persistent connection to devices to optimize real-time interactions, while others are satisfied with periodic interactions and reduced resources required. Therefore, when it is necessary for devices to initiate connections, the type of connection desired should be configured.2.4.5.2.6.5. ReconnectionStrategystrategy forPeriodic Connectionsperiodic connections 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.2.4.6. Keep-Alives2.6.6. Keep-alives forPersistent Connectionspersistent connections If a persistent connection is desired, it is the responsibility of the connection-initiator to actively test thealiveness"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 byapplicationsapplication requirements, and therefore keep-alive settings should be configurable on a per-application basis.2.4.7.2.6.7. Customizations forPeriodic Connectionsperiodic connections If a periodic connection is desired, it is necessary for the device to know how often it should connect. This delay essentially determines how long the application might have to wait to send data to the device. This setting does not constrain how often the device must wait to send data to the application, as the device should immediately connect to the application whenever it has data to send to it. A common communication pattern is that one data transmission is many times closely followed by another. For instance, if the device needs to send a notification message, there's a high probability that it will send another shortly thereafter. Likewise, the application may have a sequence of pending messages to send. Thus, it should be possible for a device to hold a connection open until some amount of time of no data being transmitted as transpired. 3. Data Model 3.1. Overview 3.1.1. Thefollowing"session-options" subtree module: ietf-netconf-server +--rw netconf-server +--rw session-options +--rw hello-timeout? uint32 +--rw idle-timeout? uint32 The above subtree illustrates how this YANG module enables configurationfor listening for remote connections, as described in [RFC6242] and [rfc5539bis]. Feature statements are used to limit both if listening is supported at all as well as for which transports. If listening for connections is supported, then the model enables configuring a listoflistening endpoints, each configured with a user-specified name (the key field), theNETCONF session options, independent of any transportto use (i.e. SSH, TLS), andor connection strategy. Please see theIP address and port to listen on.YANG module (Section 3.2) for a complete description of these configuration knobs. 3.1.2. Theport field is optional, defaulting to the transport-specific port when not configured."listen" subtree module: ietf-netconf-server +--rw netconf-server +--rwlisten*listen {"(ssh-listen or tls-listen)"}? // YANG 1.1 syntax +--rw max-sessions? uint16 +--rw endpoint* [name] +--rw name string +--rw (transport) | +--:(ssh) {ssh-listen}? | | +--rw ssh | | +--rwaddress inet:hostaddress? inet:ip-address | | +--rw port? inet:port-number | | +--rw host-keys | | +--rw host-key* string | +--:(tls) {tls-listen}? | +--rw tls | +--rwaddress inet:hostaddress? inet:ip-address | +--rw port? inet:port-number | +--rw certificates | +--rw certificate* string +--rw keep-alives +--rw interval-secs? uint8 +--rw count-max? uint8 Thefollowingabove subtree illustrates how this YANG module enables configuration forcall home,listening for remote connections, as described in[draft-ietf-netconf-call-home].[RFC6242] and [rfc5539bis]. Feature statements are used to limit both ifcall-homelistening is supported at all as well as for whichtransports, if it is.transports. Ifcall-homelistening for connections is supported, then the modelsupportsenables configuring a list ofapplications to connect to. Each application islistening endpoints, each configured with a user-specified name (the key field), the transport tobe useduse (i.e. SSH, TLS), anda list of remote endpoints, each having a name, an IP address, and an optional port. Additionally, the configuration for each remote application indicatestheconnection-type (persistent vs. periodic)IP address andassociated parameters, as well as the reconnection strategyport touse.listen on. The port field is optional, defaulting to the transport-specific port when not configured. 3.1.3. The "call-home" subtree module: ietf-netconf-server +--rw netconf-server +--rwcall-home*call-home {"(ssh-call-home or tls-call-home)"}? // YANG 1.1 syntax +--rw application* [name] +--rw name string +--rw (transport) | +--:(ssh) {ssh-call-home}? | | +--rw ssh | | +--rw endpoints | | | +--rw endpoint* [name] | | | +--rw name string | | | +--rw address inet:host | | | +--rw port? inet:port-number | | +--rwhost-key* [name]host-keys | | +--rwnamehost-key* string | +--:(tls) {tls-call-home}? | +--rw tls | +--rw endpoints | | +--rw endpoint* [name] | | +--rw name string | | +--rw address inet:host | | +--rw port? inet:port-number | +--rw certificates | +--rw certificate* string +--rw connection-type | +--rw (connection-type)? | +--:(persistent-connection) | | +--rw persistent | | +--rw keep-alives | | +--rw interval-secs? uint8 | | +--rw count-max? uint8 | +--:(periodic-connection) | +--rw periodic | +--rw timeout-mins? uint8 | +--rw linger-secs? uint8 +--rw reconnect-strategy +--rw start-with? enumeration +--rw interval-secs? uint8 +--rw count-max? uint8 Thefollowingabove subtree illustrates how this YANG module enablesauthentication of TLS client certificates and mapping TLS clients to NETCONF user names. More specifically, the "trusted-ca-certs" and "trusted-client-certs" containersconfiguration for call home, as described in [draft-ietf-netconf-call-home]. Feature statements are used toauthenticate TLS client certificates, while "cert-maps" and "psk-maps" are usedlimit both if call-home is supported at all as well as for which transports, if it is. If call-home is supported, then the model supports configuring a list of applications tomap TLS clientsconnect to. Each application is configured with a user-specified name (the key field), the transport toNETCONF user names. module: ietf-netconf-server +--rwbe used (i.e. SSH, TLS), and a list of remote endpoints, each having a name, an IP address, and an optional port. Additionally, the configuration for each remote application indicates the connection-type (persistent vs. periodic) and associated parameters, as well as the reconnection strategy to use. 3.1.4. The "ssh" subtree module: ietf-netconf-server +--rw netconf-server +--rw ssh +--ro host-keys +--ro host-key* [name] +--ro name string +--ro format-identifier string +--ro data binary +--ro fingerprint string The above subtree illustrates how this YANG module provides SSH state independent of if the NETCONF server if listening or calling home. This data-model provides a read-only listing of currently configured TLC certificates. 3.1.5. The "tls" subtree module: ietf-netconf-server +--rw netconf-server +--rwtls-client-authtls +--ro certificates | +--ro certificate* [name] | +--ro name string | +--ro data binary +--rw client-auth +--rw trusted-ca-certs | +--rw trusted-ca-cert* binary +--rw trusted-client-certs | +--rw trusted-client-cert* binary +--rw cert-maps{tls-map-certificates}? |+--rw cert-to-name* [id]|+--rw id uint32|+--rw fingerprint x509c2n:tls-fingerprint|+--rw map-type identityref|+--rw name string+--rw psk-maps {tls-map-pre-shared-keys}? +--rw psk-map* [psk-identity] +--rw psk-identity string +--rw user-name nacm:user-name-type +--rw not-valid-before? yang:date-and-time +--rw not-valid-after? yang:date-and-time +--rw key yang:hex-stringThe above subtree illustrates how this YANG module provides TLS state and enables TLS configuration independent of if the NETCONF server if listening or calling home. This data-model provides 1) a read-only listing of currently configured TLC certificates and 2) an ability to configure how client-certificates are authenicated and how authenticated client-certificates are mapped to NETCONF user names. 3.2. YANG Module This YANG module imports YANG types from [RFC6991],[RFC6536],and [draft-ietf-netmod-snmp-cfg]. RFC Ed.: update the date below with the date of RFC publication and remove this note. <CODE BEGINS> file"ietf-netconf-server@YYYY-MM-DD.yang""ietf-netconf-server@2014-10-26.yang" module ietf-netconf-server { namespace "urn:ietf:params:xml:ns:yang:ietf-netconf-server"; prefix "ncserver"; import ietf-inet-types { prefix inet; // RFC 6991 } importietf-yang-types { prefix yang; // RFC 6991 } import ietf-netconf-acm { prefix nacm; // RFC 6536 } importietf-x509-cert-to-name { prefix x509c2n; // draft-ietf-netmod-snmp-cfg } organization "IETF NETCONF (Network Configuration) Working Group"; contact "WG Web: <http://tools.ietf.org/wg/netconf/> WG List: <mailto:netconf@ietf.org> WG Chair: Mehmet Ersue <mailto:mehmet.ersue@nsn.com> WG Chair: Bert Wijnen <mailto:bertietf@bwijnen.net> Editor: Kent Watsen <mailto:kwatsen@juniper.net>"; description "This module contains a collection of YANG definitions for configuring NETCONF servers. Copyright (c) 2014 IETF Trust and the persons identified as authors of the code. All rights reserved. Redistribution and use in source and binary forms, with or without modification, is permitted pursuant to, and subject to the license terms contained in, the Simplified BSD License set forth in Section 4.c of the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info). This version of this YANG module is part of RFC XXXX; see the RFC itself for full legal notices."; // RFC Ed.: replace XXXX with actual RFC number and // remove this note // RFC Ed.: please update the date to the date of publication revision"YYYY-MM-DD""2014-10-26" { // YYYY-MM-DD description "Initial version"; reference "RFC XXXX: NETCONF Server Configuration Model"; } // Features feature ssh-listen { description "The ssh-listen feature indicates that the NETCONF server can open a port to listen for incoming client connections."; } feature ssh-call-home { description "The ssh-call-home feature indicates that the NETCONF server can connect to a client."; reference "RFC XXXX: Reverse Secure Shell (Reverse SSH)"; } feature tls-listen { description "The tls-listen feature indicates that the NETCONF server can open a port to listen for incoming client connections."; } feature tls-call-home { description "The tls-call-home feature indicates that the NETCONF server can connect to a client."; }feature tls-map-certificates { description "The tls-map-certificates feature indicates that the NETCONF server implements mapping X.509 certificates to NETCONF usernames."; } feature tls-map-pre-shared-keys { description "The tls-map-pre-shared-keys feature indicates that the NETCONF server implements mapping TLS pre-shared keys to NETCONF usernames."; }//Module'stop-level container (groupings below) container netconf-server { description "Top-level container for NETCONF server configuration.";list listen { key name; description "List of endpoints to listen for connections on."; //if-feature "(ssh-listen or tls-listen)"; uses listen-config; } list call-home { key name; description "List of applications to call-home to."; //if-feature "(ssh-call-home or tls-call-home)";usescall-home-config; } container tls-client-auth { //if-feature "(tls-listen or tls-call-home)"; description "Container for TLS client authentication configuration.";session-options-container; usestrusted-ca-certs-grouping;listen-container; usestrusted-client-certs-grouping;call-home-container; usescert-maps-grouping;ssh-container; usespsk-maps-grouping;tls-container; }} // Groupingsgroupinglisten-configsession-options-container { description"Grouping""; container session-options { description "NETCONF session options, independent of transport or connection strategy."; leaf hello-timeout { type uint32 { range "0 | 10 .. 3600"; } units "seconds"; default '600'; description "Specifies the number of seconds that a session may exist before the hello PDU is received. A session will be dropped if no hello PDU is received before this number of seconds elapses. If this parameter is set to zero, then the server will wait forever for a hello message, and not drop any sessions stuck in 'hello-wait' state. Setting this parameter to zero may permit denial of service attacks, since only a limited number of concurrent sessions are supported by the server."; } leaf idle-timeout { type uint32 { range "0 | 10 .. 360000"; } units "seconds"; default '3600'; description "Specifies the number of seconds that a session may remain idle without issuing any RPC requests. A session will be dropped if it is idle for an interval longer than this number of seconds. Sessions that have a notification subscription active are never dropped. If this parameter is set to zero, then the server will never drop a session because it is idle."; } } } grouping listen-container { description ""; container listenconfiguration.";{ description "Configures listen behavior"; //if-feature "(ssh-listen or tls-listen)"; leaf max-sessions { type uint16 { range "0 .. 1024"; } default '0'; description "Specifies the maximum number of concurrent sessions that can be active at one time. The value 0 indicates that no artificial session limit should be used."; } list endpoint { key name; description "List of endpoints to listen for connections on."; leaf name { type string; description "An arbitrary name for the listen endpoint."; } choice transport { mandatory true; description "Selects between SSH and TLS transports."; case ssh { if-feature ssh-listen; container ssh { description "SSH-specific listening configuration for inbound connections."; useslisten-per-transport-configaddress-and-port-grouping { refine port { default 830; } } uses host-keys-container; } } case tls { if-feature tls-listen; container tls { description "TLS-specific listening configuration for inbound connections."; useslisten-per-transport-configaddress-and-port-grouping { refine port { default 6513; } } uses certificates-container; } } } uses keep-alives-container { refine keep-alives/interval-secs { default 0; // disabled by default for listen connections } } } } } groupinglisten-per-transport-configcall-home-container { description"Provides the configuration of the NETCONF server to open one""; container call-home { //if-feature "(ssh-call-home ormore ports to listen for incoming client connections."; leaf addresstls-call-home)"; description "Configures call-home behavior"; list application {type inet:host; mandatory true;key name; description"The local IP address/name"List ofthe interfaceapplications tolisten on."; }call-home to."; leafportname { typeinet:port-number; description "The local port number on this interface the NETCONF server listens on."; } } grouping call-home-config { description "Grouping for call-home configuration."; leaf name { type string;string; description "An arbitrary name for the remote application."; }uses call-home-transport-config; uses call-home-connection-type-config; uses call-home-reconnection-strategy-config; } grouping call-home-transport-config { description "Grouping for call-home specific transport selection.";choice transport { mandatory true; description "Selects between SSH and TLS transports."; case ssh { if-feature ssh-call-home; container ssh { description "Specifies SSH-specific call-home transport configuration."; usescall-home-per-transport-configendpoints-container { refine endpoints/endpoint/port { default9999;8888; // pending IANA assignment } }list host-key { key name; min-elements 1; ordered-by user; description "User-ordered list of host-keys the SSH server should advertise."; leaf name { type string; mandatory true; description "The name of a host key the device should advertise during the SSH key exchange."; } }uses host-keys-container; } } case tls { if-feature tls-call-home; container tls { description "Specifies TLS-specific call-home transport configuration."; usescall-home-per-transport-configendpoints-container { refine endpoints/endpoint/port { default 9999; // pending IANA assignment } } uses certificates-container; } } }} grouping call-home-per-transport-config { description "Grouping for transport-specific configuration for call-home connections."; container endpoints { description "Container for the list of endpoints."; list endpoint { key name; min-elements 1; ordered-by user; description "User-ordered list of endpoints for this application. Defining more than one enables high-availability."; leaf name { type string; description "An arbitrary name for the endpoint to connect to."; } leaf address { type inet:host; mandatory true; description "The hostname or IP address of the endpoint. If a hostname is provided and DNS resolves to more than one IP address, the device SHOULD try all of the ones it can based on how its networking stack is configured (e.g. v4, v6, dual-stack)."; } leaf port { type inet:port-number; description "The IP port for this endpoint. The device will use the IANA-assigned well-known port if not specified."; } } } } grouping call-home-connection-type-config { description "Grouping to define connection-type for call-home based connections.";container connection-type { description "Indicates thenetwork manager'sNETCONF client's preference for how the device's connection is maintained."; choice connection-type { default persistent-connection; description "Selects between persistent and periodic connections."; case persistent-connection { container persistent { description "Maintain a persistent connection to thenetwork manager.NETCONF client. If the connection goes down, immediately start trying to reconnect to it, using the reconnection strategy. This connection type minimizes anymanager-to-deviceNETCONF client to NETCONF server data-transfer delay, albeit at the expense of holding resources longer.";container keep-alivesuses keep-alives-container {description "Configures keep-alive policy, to proactively detect when a persistent connection to an endpoint has dropped."; leaf interval-secsrefine keep-alives/interval-secs {type uint8; units seconds;default 15;description "Sets a timeout interval in// 15 secondsafter which if no data has been received from the manager's endpoint, a message will be sent to request a response from the endpoint. A value of '0' indicates that no keep-alive messages should be sent."; } leaf count-max { type uint8; default 3; description "Sets the number of keep-alive messages that may be sent without receiving any data from the manager's endpoint before assuming the endpoint is no longer alive. If this threshold is reached, the transport-level connection will be disconnected (thus triggering the reconnection strategy). The interval timer is reset after each transmission, thus an unresponsive endpoint will be disconnected after about count-max * interval-secs seconds.";for call-home sessions } } } } case periodic-connection { container periodic { description "Periodically connect tonetwork manager,NETCONF client, using the reconnection strategy, soitthe NETCONF client canflush anydeliver pendingdata it may be holding. This connection type minimizes resources held open, albeit atmessages to theexpense of longer manager-to-device data-transfer delay. Note that for device-to-manager data,NETCONF server. For messages thedataNETCONF server wants to send to to the NETCONF client, the NETCONF server shouldbe sent immediately, connectingproactively connect tonetwork manager firstthe NETCONF client, if notalready.";already, to send the messages immediately."; leaf timeout-mins { type uint8; units minutes; default 5; description "The maximum amount of unconnected time the device will wait until establishing a connection to thenetwork managerNETCONF client again. The device MAY establish a connection before this time if it has data it needs to send to thenetwork manager.NETCONF client. Note: this value differs from the reconnection strategy's interval-secs value."; } leaf linger-secs { type uint8; units seconds; default 30; description "The amount of time the device should wait after last receiving data from or sending data to thenetwork manager'sNETCONF client's endpoint before closing its connection to it. This is an optimization to prevent unnecessary connections."; } } } } }} grouping call-home-reconnection-strategy-config { description "Grouping for reconnection strategy.";container reconnect-strategy { description "The reconnection strategy guides how a device reconnects to an application, after losing a connection to it, even if due to a reboot. The device starts with the specified endpoint, tries to connect to it count-max times, waiting interval-secs between each connection attempt, 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 connectedto.";to. NETCONF servers SHOULD support this flag across reboots."; } } default first-listed; description "Specifies which of the application's endpoints the device should start with when trying to connect to the application. If no previous connection has ever been established, last-connected defaults to the first endpoint listed."; } leaf interval-secs { type uint8; units seconds; default 5; description "Specifies the time delay between connection attempts to the same endpoint. Note: this value differs from the periodic-connection's timeout-mins value."; } leaf count-max { type uint8; default 3; description "Specifies the number times the device tries to connect to a specific endpoint before moving on to the next endpoint in the list (round robin)."; } } } } } groupingtrusted-ca-certs-groupingssh-container { description"Grouping for trusted-ca-certs container.";""; containertrusted-ca-certsssh { description"A list of Certificate Authority (CA) certificates that a NETCONF server can use"Configures SSH properties not specific toauthenticate a NETCONF client's certificate. A client's certificate is authenticated if its Issuer matches one oftheconfigured trusted CA certificates."; leaf-list trusted-ca-certlisten or call-home use-cases"; //if-feature "(ssh-listen or ssh-call-home)"; container host-keys {type binary; ordered-by system;config false; description "Parent container for a list of host keys"; list host-key { key name; description "A read-only list of host-keys supported by server"; leaf name { type string; description "Common name for the host-key"; } leaf format-identifier { type string; mandatory true; description "ssh-dss, ssh-rsa, x509v3-rsa2048-sha256, etc."; reference "RFC 4253: SSH Transport Layer Protocol, section 6.6 RFC 6187: X.509v3 Certificates for SSH, section 3"; } leaf data { type binary; mandatory true; description "Key-specific binary encoding."; reference "RFC 4253: SSH Transport Layer Protocol, section 6.6"; } leaf fingerprint { type string; mandatory true; description "c1:b1:30:29:d7:b8:de:6c:97:77:10:d7:46:41:63:87"; reference "RFC 4716: The Secure Shell (SSH) Public Key File Format, section 4"; } } } } } grouping tls-container { description ""; container tls { description "Configures TLS properties not specific to the listen or call-home use-cases"; //if-feature "(tls-listen or tls-call-home)"; container certificates { config false; description "Parent container for a list of certificates"; list certificate { key name; description "A list of certificates"; leaf name { type string; description "the certificate's common name"; } leaf data { type binary; mandatory true; description "The binary certificate structure, as specified by RFC 5246, Section 7.4.2, i.e.,: opaque ASN.1Cert<1..2^24-1>;"; } } } container client-auth { description "Container for TLS client authentication configuration."; container trusted-ca-certs { description "A list of Certificate Authority (CA) certificates that a NETCONF server can use to authenticate NETCONF client certificates. A client's certificate is authenticated if there is a chain of trust to a configured trusted CA certificate. Note, in the TLS protocol, the client certificate MAY be accompanied with additional certificates forming a chain of trust. The client's certificate is authenticated if there is path-validation from any of the certificates it presents to a configured trust anchor."; leaf-list trusted-ca-cert { type binary; ordered-by system; description "The binary certificate structure as specified by RFC 5246, Section 7.4.6, i.e.,: opaque ASN.1Cert<1..2^24>; "; reference "RFC 5246: The Transport Layer Security (TLS) Protocol Version 1.2"; } }} grouping trusted-client-certs-grouping { description "Grouping for trusted-client-certs container.";container trusted-client-certs { description "A list of client certificates that a NETCONF server can use to authenticate a NETCONF client's certificate. A client's certificate is authenticated if it is an exact match to a configured trusted client certificates."; leaf-list trusted-client-cert { type binary; ordered-by system; description "The binary certificate structure, as specified by RFC 5246, Section 7.4.6, i.e.,: opaque ASN.1Cert<1..2^24>; "; reference "RFC 5246: The Transport Layer Security (TLS) Protocol Version 1.2"; } }} // Objects for deriving NETCONF usernames from X.509 // certificates. grouping cert-maps-grouping { description "Grouping for cert-maps container.";container cert-maps {if-feature tls-map-certificates;uses x509c2n:cert-to-name; description "The cert-maps container is used by a 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."; } }// Objects for deriving NETCONF usernames from TLS // pre-shared keys.} } groupingpsk-maps-groupinghost-keys-container { description"Grouping for psk-maps container.";""; containerpsk-mapshost-keys {if-feature tls-map-pre-shared-keys;description"During the TLS Handshake,"Parent container for theclient indicates which key to use by including a PSK identity inlist of host-keys."; leaf-list host-key { type string; min-elements 1; ordered-by user; description "User-ordered list of host-keys theTLS ClientKeyExchange message. OnSSH server considers when composing theNETCONFlist of serverside, this PSK identity is usedhost key algorithms it will send tolook up an entry in the psk-map list. If such an entry is found, and the pre-shared keys match, thentheclient is authenticated.client. TheNETCONF server uses thevaluefromof theuser-name leaf instring is thepsk-map listname of a host-key configured on the system, as returned by /netconf-server/ssh/host-keys/host-key/name."; reference "RFC 4253: The SSH Transport Layer Protocol, Section 7"; } } } grouping certificates-container { description ""; container certificates { description "Parent container for theNETCONF username. Iflist of certificates."; leaf-list certificate { type string; min-elements 1; description "Unordered list of certificates theNETCONFTLS servercannot find an entry in the psk-map list, or ifcan pick from when sending its Server Certificate message. The value of thepre-shared keys do not match, thenstring is theNETCONF server terminatesname of a certificate configured on theconnection.";system, as returned by /netconf-server/tls/certificates/certificate/name"; reference "RFC4279: Pre-Shared Key Ciphersuites5246: The TLS Protocol, Section 7.4.2"; } } } grouping address-and-port-grouping { description "a common grouping"; leaf address { type inet:ip-address; description "The IP address of the interface to listen on."; } leaf port { type inet:port-number; description "The local port number on this interface the NETCONF server listens on."; } } grouping endpoints-container { description "Grouping forTransport Layer Security (TLS)";transport-specific configuration for call-home connections."; container endpoints { description "Container for the list of endpoints."; listpsk-mapendpoint { keypsk-identity;name; min-elements 1; ordered-by user; description"List"User-ordered list of endpoints for this application. Defining more than one enables high-availability."; leaf name { type string; description "An arbitrary name for the endpoint to connect to."; } leaf address { type inet:host; mandatory true; description "The hostname or IP address or hostname of the endpoint. If apre-shared key mappings.";hostname is provided and DNS resolves to more than one IP address, the device SHOULD try all of the ones it can based on how its networking stack is configured (e.g. v4, v6, dual-stack)."; } leafpsk-identityport { typestring;inet:port-number; description "ThePSK identity encoded asIP port for this endpoint. The device will use the IANA-assigned well-known port if not specified."; } } } } grouping keep-alives-container { description ""; container keep-alives { description "Configures the keep-alive policy, to proactively test the aliveness of the NETCONF client, in order to know when aUTF-8 string. For details how certain common PSK identity formats cannew call home connection should beencodedestablished. Keepalive implementation is described inUTF-8, see section 5.1. ofRFC4279.";XXXX, section 4."; reference "RFC4279: Pre-Shared Key Ciphersuites for Transport Layer Security (TLS)"; }XXXX: NETCONF Server Configuration Model Section 4"; leafuser-nameinterval-secs { typenacm:user-name-type; mandatory true;uint8; units seconds; description"The"Sets a timeout interval in seconds after which if no data has been received from the NETCONFusername associated with this PSK identity.";client, a message will be sent to request a response from the NETCONF client. A value of '0' indicates that no keep-alive messages should be sent."; } leafnot-valid-beforecount-max { typeyang:date-and-time;uint8; default 3; description"This PSK identity is not valid"Sets the number of keep-alive messages that may be sent without receiving any data from the NETCONF client before assuming thegiven date and time."; } leaf not-valid-after { type yang:date-and-time; description "This PSK identityNETCONF client isnot valid afterno longer alive. If this threshold is reached, thegiven date and time."; } leaf key { type yang:hex-string; mandatory true; nacm:default-deny-all; description "The key associated withtransport-level connection will be disconnected, which will trigger thePSK identity"; reference "RFC 4279: Pre-Shared Key Ciphersuites for Transport Layer Security (TLS)"; }reconnection strategy). The interval timer is reset after each transmission, thus an unresponsive NETCONF client will be dropped after ~count-max * interval-secs seconds."; } } } } <CODE ENDS> 4.Keep-AlivesImplementation strategy forSSH and TLSkeep-alives One of the objectives listed above,Keep-AlivesKeep-alives forPersistent Connectionspersistent connections (Section2.4.6)2.6.6), indicates a need for a "keep-alive" mechanism. This section specifies how the NETCONF keep-alive mechanism is to beimplemented.implemented for both the SSH and TLS transports. Both SSH and TLS have the ability to supportkeep-alives.keep-alives securely. Usingthese mechanisms,the strategies listed below, the keep-alive messages are sent inside the encryptedtunnel, thus thwarting spoof attacks.transport sessions. 4.1. Keep-alives for SSH The SSH keep-alive solution that is expected to be usedwhen configured using the data model defined in this documentis ubiquitous in practice, though never being explicitly defined in an RFC. The strategy used is to purposely send a malformed request message with a flag set to ensure a response. More specifically, per section 4 of [RFC4253], either SSH peer can send a SSH_MSG_GLOBAL_REQUEST message with "want reply" set to '1' and that, if there is an error, will get back a SSH_MSG_REQUEST_FAILURE response. Similarly, section 5 of [RFC4253] says that either SSH peer can send a SSH_MSG_CHANNEL_REQUEST message with "want reply" set to '1' and that, if there is an error, will get back a SSH_MSG_CHANNEL_FAILURE response. To ensure that the request will fail, current implementations of this keep-alive strategy (e.g. OpenSSH's `sshd` server) send an invalid "request name" or "request type", respectively. Abiding to the extensibility guidelines specified in Section 6 of [RFC4251], these implementations use the "name@domain". For instance, when configured to send keep-alives, OpenSSH sends the string "keepalive@openssh.com". In order to remain compatible with existing implementations, this draft does not require a specific "request name" or "request type" string beused.used, implementations are free to pick values of their choosing. 4.2. Keep-alives for TLS The TLS keep-alive solution that is expected to be used is defined in [RFC6520]. This solution allows both peers to advertise if they can receive heartbeat request messages from its peer. For standard NETCONF over TLS connections, devices SHOULD advertise "peer_allowed_to_send", as per [RFC6520]. This advertisement is not a "MUST" in order to grandfather existing NETCONF over TLS implementations. For NETCONFover TLSCall Home, the network management system MUST advertise "peer_allowed_to_send" per [RFC6520]. This is a "MUST" so as to ensure devices can depend in it always being there for call home connections, which isconvenientlywhen keep-alives are needed the most. 5. Security Considerations The YANG modules defined in this memo are designed to be accessed via the NETCONF protocol [RFC6241]. Authorization for access to specific portions of conceptual data and operations within this module is provided by the NETCONF access control model (NACM) [RFC6536]. There are a number of data nodes defined in the "ietf-netconf-server"and "ietf-system-tls-auth"YANGmodulesmodule which arewritable/creatable/ deletable (i.e., config true, which is the default). These data nodesreadable and/or writable that may be considered sensitive or vulnerable in some network environments. Write and read operations to these data nodes can have a negative effect on network operations. It is thus important to control write and read access to these data nodes. Below are the data nodes and theirsensitivity/vulnerability. ietf-netconf-server:sensitivity/ vulnerability. netconf-server/tls/client-auth/trusted-ca-certs: oNone. ietf-system-tls-auth:This container contains certificates that the system is to use as trust anchors for authenticating TLS-specific client certificates. Write access to this node should be protected. netconf-server/tls/client-auth/trusted-client-certs: o/system/authentication/tls/psk-maps/psk-map/user-name:Thisleafcontainer contains certificates that the system is to trust directly when authenticating TLS-specific client certificates. Write access to this node should be protected. netconf-server/tls/client-auth/cert-map: o This container contains a user name that some deployments may consider sensitive information.o /system/authentication/tls/psk-maps/psk-map/key: This leaf node contains a shared key that remote clients useRead access toauthenticate themselvesthis node may need tothe system. This value should notbereadable or writable by anyone by default.guarded. 6. IANA Considerations This document registers two URIs in the IETF XML registry [RFC2119]. Following the format in [RFC3688], the following registrations are requested: 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. URI: urn:ietf:params:xml:ns:yang:ietf-system-tle-auth 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]. name: ietf-netconf-server namespace: urn:ietf:params:xml:ns:yang:ietf-netconf-server prefix: ncserver reference: RFC XXXX name: ietf-system-tls-auth namespace: urn:ietf:params:xml:ns:yang:ietf-system-tls-auth prefix: sys-tls-auth reference: RFC XXXX 7. Other Considerations The YANG module define herein does not itself support virtual routing and forwarding (VRF). It is expected that external modules will augment in VRF designations when needed. 8. Acknowledgements 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, David Lamparter, Alan Luchuk, Ladislav Lhotka, Radek Krejci, Tom Petch, and Phil Shafer. Juergen Schoenwaelder and was partly funded by Flamingo, a Network of Excellence project (ICT-318488) supported by the European Commission under its Seventh Framework Programme. 9. References 9.1. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC4251] Ylonen, T. and C. Lonvick, "The Secure Shell (SSH) Protocol Architecture", RFC 4251, January 2006. [RFC4253] Ylonen, T. and C. Lonvick, "The Secure Shell (SSH) Transport Layer Protocol", RFC 4253, January 2006. [RFC6020] Bjorklund, M., "YANG - A Data Modeling Language for the Network Configuration Protocol (NETCONF)", RFC 6020, October 2010. [RFC6241] Enns, R., Bjorklund, M., Schoenwaelder, J., and A. Bierman, "Network Configuration Protocol (NETCONF)", RFC 6241, June 2011. [RFC6242] Wasserman, M., "Using the NETCONF Protocol over Secure Shell (SSH)", RFC 6242, June 2011. [RFC6520] Seggelmann, R., Tuexen, M., and M. Williams, "Transport Layer Security (TLS) and Datagram Transport Layer Security (DTLS) Heartbeat Extension", RFC 6520, February 2012. [RFC6536] Bierman, A. and M. Bjorklund, "Network Configuration Protocol (NETCONF) Access Control Model", RFC 6536, March 2012. [RFC6991] Schoenwaelder, J., "Common YANG Data Types", RFC 6991, July 2013. [draft-ietf-netconf-call-home] Watsen, K., "NETCONF Call Home", draft-ieft-netconf-call- home-00 (work in progress), 2014. [draft-ietf-netmod-snmp-cfg] Bjorklund, M. and J. Schoenwaelder, "A YANG Data Model for SNMP Configuration",draft-ietf-netmod-snmp-cfg-03draft-ietf-netmod-snmp-cfg-08 (work in progress),November 2013.September 2014. [rfc5539bis] Badra, M., Luchuk, A., and J. Schoenwaelder, "Using the NETCONF Protocol over Transport Layer Security (TLS)", draft-ietf-netconf-rfc5539bis-04 (work in progress), October 2013. 9.2. Informative References [RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688, January 2004. Appendix A. Examples A.1. SSH Transport Configuration + State The following example illustrastes the <get> response from a NETCONF server that only supports SSH, both listening for incoming connections as well as calling home to a single application having two endpoints. Please also note that the list of host-keys at the end is read-only operational state. <netconf-server xmlns="urn:ietf:params:xml:ns:yang:ietf-netconf-server"> <listen> <endpoint> <name>foo bar</name> <ssh><port>831</port><address>11.22.33.44</address> <host-keys> <host-key>my-rsa-key</host-key> <host-key>my-dss-key</host-key> </host-keys> </ssh> </endpoint> </listen> <call-home> <application> <name>config-mgr</name> <ssh> <endpoints> <endpoint> <name>east-data-center</name> <address>11.22.33.44</address> </endpoint> <endpoint> <name>west-data-center</name> <address>55.66.77.88</address> </endpoint> </endpoints> <host-keys> <host-key>my-call-home-x509-key</host-key> </host-keys> </ssh> </application> </call-home> <ssh> <host-keys> <host-key> <name>my-rsa-key</name> <format-identifier>ssh-rsa</format-identifier> <data> <!-- base64 reformated for draft --> AAAAB3NzaC1yc2EAAAABIwAAAQEA7D2lxYg3+WD97RZqZtO8bUU8QpIl6g9 X11kZHZ8NgSIR+x2H1MHCD5sEjmx/B6JIouK5eBvbJE9FFV3phsl62fupN6 Y4EmXosC6iqpuI41dcGA63XCQ1OenWG4ppdq1f8tlecSrmEcLw7MKPzBHK6 rNQTciqMuVuLPOKwBu/54QAiUwvvHKAsk8bkN9YxEJ1NTV1FFQmvMOADVcD 2qqPangETwV5zInW8AEkBbLccM/mmHucGNS81axXR3V9R5KgXF2DyGB47d2 k6iOnGa3LBIOYi/5Q+O8IFUlO+kytfqwuFgUc+Mx7aKReSIAPov3owVjeBL KWsvjD24UO68qtwQ== </data> <fingerprint> c1:b1:30:29:d7:b8:de:6c:97:77:10:d7:46:41:63:87 </fingerprint> </host-key> <host-key> <name>my-dss-key</name> <format-identifier>ssh-dss</format-identifier> <data> <!-- base64 reformated for draft --> AAAAB3NzaC1kc3MAAACBAIq7XfGmZKJgibJEIMzj70YMVfpeewBCj89VrUS gLsJmxP/TrXFuhzW2UIaI8sePMYUXj/Vgp5DUD+eBSBkHMH4ga0U5t/clqn y73x8Vg6LQg9f0OTaUnpRWbWrdac7U5/BRBTtMA3amHZhHrKs7BrCepS/y8 cUbxBCPF3aYMK/5AAAAFQC7wetEbDwghYtz8Z3xIwDdxs6mOwAAAIBursEk jnvs5zzyUH7iNiyBojDoyrsq81jPM6KopkfA5Ypp2KTySPev/mkL0SoVfIb +HttVfQ3Q63+sf1Qyk+gUtniSdN2AqtFQYKxtTcXim4McWk6IixkYFP8kkt 02t9Hsl0eXvltmogrlRsiuJsTAbFS+QTeq4OGTODCT5jjVdQAAAIA2llpZg y5v46lGt4dQhkH8ytyMGyjBRPF6rm51msinX3lMR9xfwTaS7ZYP0b6HJt5M sQI+m7iIYaVFB1oC8niXbkkavLcxhGpNVkwE2INWS4TIBbTQhivuoE+dMYY KauLQxqSUjixJk3LjhCQb </data> <fingerprint> c1:b1:30:29:d7:b8:de:6c:97:77:10:d7:46:41:63:87 </fingerprint> </host-key> <host-key> <name>my-call-home-x509-key</name> <format-identifier>x509v3-rsa2048-sha256</format-identifier> <data> <!-- base64 reformated for draft --> AAAAB3NzaC1yc2EAAAABIwAAAQEAyBLl90dPUGX7Es12q7YKkw6v8WgWop+ B62zhT39C+yvslMIwIqgHYii0h/TGktahKpBwssawfhvAZoMF/nOyO3yDPD pQxNrA76H7owNOjG5206QHDYfVALKPvxgrDy/6BjsR9MayOGkZTSL6GRFSl g7ivT9AIR9E5qXmP+1z+IDufRlpwfaGfpZAxjJLEwzAjFAIwXsXKJ5FH/QP mfC6gxfhqpt9rJCDlgqmzrXi8dXKsFUC3/o1lzezqTXTV1iMETTuCHgWegF 5QcX2baBdFgCnkd1SnftVoBHVnvXA1euRqgiG3fMNK4rct0D99D+GI+kZc+ vQyUdCw3dPlhXPZw== </data> <fingerprint> 97:77:10:29:d7:b8:de:6c:97:77:30:29:d7:41:63:87 </fingerprint> </host-key> </host-keys> </ssh> </netconf-server> A.2. TLS Transport Configuration + State The following example illustrastes the <get> response from a NETCONF server that only supports TLS, both listening for incoming connections as well as calling home to a single application having two endpoints. Please note also the configurations for authenticating client certificates and mappings authenticated certificates to NETCONF user names. <netconf-server xmlns="urn:ietf:params:xml:ns:yang:ietf-netconf-server"> <listen><name>foo bar</name> <ssh> <port>831</port> </ssh><endpoint> <name>primary-netconf-endpoint</name> <tls> <address>11.22.33.44</address> <certificates> <certificate>fw1.east.example.com</certificate> </certificates> </tls> </endpoint> </listen> <call-home> <application> <name>config-mgr</name> <tls> <endpoints> <endpoint> <name>east-data-center</name> <address>11.22.33.44</address> </endpoint> <endpoint> <name>west-data-center</name> <address>55.66.77.88</address> </endpoint> </endpoints> <certificates> <certificate>fw1.east.example.com</certificate> </certificates> </tls> </application> </call-home><tls-client-auth><tls> <certificates> <certificate> <name>fw1.east.example.com</name> <data> <!-- base64 reformated for draft --> AAAAB3NzaC1yc2EAAAABIwAAAQEA7D2lxYg3+WD97RZqZtO8bUU8QpIl6g9 X11kZHZ8NgSIR+x2H1MHCD5sEjmx/B6JIouK5eBvbJE9FFV3phsl62fupN6 Y4EmXosC6iqpuI41dcGA63XCQ1OenWG4ppdq1f8tlecSrmEcLw7MKPzBHK6 rNQTciqMuVuLPOKwBu/54QAiUwvvHKAsk8bkN9YxEJ1NTV1FFQmvMOADVcD 2qqPangETwV5zInW8AEkBbLccM/mmHucGNS81axXR3V9R5KgXF2DyGB47d2 k6iOnGa3LBIOYi/5Q+O8IFUlO+kytfqwuFgUc+Mx7aKReSIAPov3owVjeBL KWsvjD24UO68qtwQ== </data> </certificate> </certificates> <client-auth> <trusted-ca-certs> <trusted-ca-cert> QW4gRWFzdGVyIGVnZywgZm9yIHRob3NlIHdobyBtaWdodCBsb29rICA6KQo= </trusted-ca-cert> </trusted-ca-certs> <trusted-client-certs> <trusted-client-cert> SSBhbSB0aGUgZWdnIG1hbiwgdGhleSBhcmUgdGhlIGVnZyBtZW4uCg== </trusted-client-cert> <trusted-client-cert> SSBhbSB0aGUgd2FscnVzLCBnb28gZ29vIGcnam9vYi4K </trusted-client-cert> </trusted-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>11:0A:05:11:00</fingerprint> <map-type>x509c2n:specified</map-type> <name>Joe Cool</name> </cert-to-name> </cert-maps><psk-maps> <psk-map> <psk-identity>a8gc8]klh59</psk-identity> <user-name>admin</user-name> <not-valid-before>2013-01-01T00:00:00Z</not-valid-before> <not-valid-after>2014-01-01T00:00:00Z</not-valid-after> </psk-map> </psk-maps> </tls-client-auth></client-auth> </tls> </netconf-server> Appendix B. Change Log B.1. 00 to 01 o Restructured document so it flows better o Added trusted-ca-certs and trusted-client-certs objects into the ietf-system-tls-auth module B.2. 01 to 02 o removed the "one-to-many" construct o removed "address" as a key field o removed "network-manager" terminology o moved open issues to github issues o brought TLS client auth back into model B.3. 02 to 03 o fixed tree diagrams and surrounding text B.4. 03 to 04 o reduced the number of grouping statements o removed psk-maps and associated feature statements o added ability for listen/call-home instances to specify which host-keys/certificates (of all listed) to use o clarified that last-connected should span reboots o added missing "objectives" for selecting which keys to use, authenticating client-certificates, and mapping authenticated client-certificates to usernames o clarified indirect client certificate authentication o added keep-alive configuration for listen connections o added global-level NETCONF session parameters Appendix C. Open Issues Please see: https://github.com/netconf-wg/server-model/issues. Authors' Addresses Kent Watsen Juniper Networks EMail: kwatsen@juniper.net Juergen Schoenwaelder Jacobs University Bremen EMail: j.schoenwaelder@jacobs-university.de