--- 1/draft-ietf-netconf-server-model-06.txt 2015-07-06 08:15:11.662003523 -0700 +++ 2/draft-ietf-netconf-server-model-07.txt 2015-07-06 08:15:11.842007872 -0700 @@ -1,61 +1,56 @@ NETCONF Working Group K. Watsen Internet-Draft Juniper Networks Intended status: Standards Track J. Schoenwaelder -Expires: August 6, 2015 Jacobs University Bremen - February 2, 2015 +Expires: January 7, 2016 Jacobs University Bremen + July 6, 2015 NETCONF Server and RESTCONF Server Configuration Models - draft-ietf-netconf-server-model-06 + draft-ietf-netconf-server-model-07 Abstract This draft defines a NETCONF server configuration data model and a RESTCONF server configuration data model. These data models enable configuration of the NETCONF and RESTCONF services themselves, including which transports are supported, what ports the servers - listens on, whether call-home is supported, and associated - parameters. + listen on, call-home parameters, client authentication, and other + related configuration parameters. Editorial Note (To be removed by RFC Editor) 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. Please note that no other RFC Editor instructions are specified anywhere else 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: - o draft-ietf-netconf-rfc5539bis - o draft-ietf-netconf-restconf o draft-ietf-netconf-call-home Artwork in this document contains shorthand references to drafts in progress. Please apply the following replacements: o "VVVV" --> the assigned RFC value for this draft - o "WWWW" --> the assigned RFC value for draft-ietf-netconf- - rfc5539bis - o "XXXX" --> the assigned RFC value for draft-ietf-netconf-restconf + o "YYYY" --> the assigned RFC value for draft-ietf-netconf-call-home o "ZZZZ" --> the assigned RFC value for draft-thomson-httpbis-cant - Artwork in this document contains placeholder values for ports pending IANA assignment from "draft-ietf-netconf-call-home". Please apply the following replacements: o "7777" --> the assigned port value for "netconf-ch-ssh" o "8888" --> the assigned port value for "netconf-ch-tls" o "9999" --> the assigned port value for "restconf-ch-tls" @@ -55,21 +50,21 @@ o "7777" --> the assigned port value for "netconf-ch-ssh" o "8888" --> the assigned port value for "netconf-ch-tls" o "9999" --> the assigned port value for "restconf-ch-tls" Artwork in this document contains placeholder values for the date of publication of this draft. Please apply the following replacement: - o "2015-02-02" --> the publication date of this draft + o "2015-07-06" --> the publication date of this draft The following two Appendix sections are to be removed prior to publication: o Appendix B. Change Log o Appendix C. Open Issues Status of This Memo @@ -79,104 +74,117 @@ Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at http://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." - This Internet-Draft will expire on August 6, 2015. + This Internet-Draft will expire on January 7, 2016. Copyright Notice Copyright (c) 2015 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 . . . . . . . . . . . . . . . . . . . . . . . . 4 1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 4 - 1.2. Tree Diagrams . . . . . . . . . . . . . . . . . . . . . . 4 + 1.2. Tree Diagrams . . . . . . . . . . . . . . . . . . . . . . 5 2. Objectives . . . . . . . . . . . . . . . . . . . . . . . . . 5 2.1. Support all NETCONF and RESTCONF transports . . . . . . . 5 2.2. Enable each transport to select which keys to use . . . . 5 2.3. Support authenticating NETCONF/RESTCONF clients - certificates . . . . . . . . . . . . . . . . . . . . . . 5 + certificates . . . . . . . . . . . . . . . . . . . . . . 6 2.4. Support mapping authenticated NETCONF/RESTCONF client certificates to usernames . . . . . . . . . . . . . . . . 6 - 2.5. Support both Listening for connections and Call Home . . 6 + 2.5. Support both listening for connections and call home . . 6 2.6. For Call Home connections . . . . . . . . . . . . . . . . 6 - 2.6.1. Support more than one northbound application . . . . 6 - 2.6.2. Support applications having more than one server . . 6 - 2.6.3. Support a reconnection strategy . . . . . . . . . . . 6 + 2.6.1. Support more than one NETCONF/RESTCONF client . . . . 6 + 2.6.2. Support NETCONF/RESTCONF clients having more than one + endpoint . . . . . . . . . . . . . . . . . . . . . . 6 + 2.6.3. Support a reconnection strategy . . . . . . . . . . . 7 2.6.4. Support both persistent and periodic connections . . 7 2.6.5. Reconnection strategy for periodic connections . . . 7 2.6.6. Keep-alives for persistent connections . . . . . . . 7 - 2.6.7. Customizations for periodic connections . . . . . . . 7 - 3. The NETCONF Server Configuration Model . . . . . . . . . . . 8 - 3.1. Overview . . . . . . . . . . . . . . . . . . . . . . . . 8 - 3.1.1. The "session-options" subtree . . . . . . . . . . . . 8 - 3.1.2. The "listen" subtree . . . . . . . . . . . . . . . . 8 - 3.1.3. The "call-home" subtree . . . . . . . . . . . . . . . 9 - 3.1.4. The "ssh" subtree . . . . . . . . . . . . . . . . . . 11 - 3.1.5. The "tls" subtree . . . . . . . . . . . . . . . . . . 11 - 3.2. YANG Module . . . . . . . . . . . . . . . . . . . . . . . 12 - 4. The RESTCONF Server Configuration Model . . . . . . . . . . . 25 - 4.1. Overview . . . . . . . . . . . . . . . . . . . . . . . . 25 - 4.1.1. The "listen" subtree . . . . . . . . . . . . . . . . 25 - 4.1.2. The "call-home" subtree . . . . . . . . . . . . . . . 26 - 4.1.3. The "client-cert-auth" subtree . . . . . . . . . . . 28 - 4.2. YANG Module . . . . . . . . . . . . . . . . . . . . . . . 28 - 5. Implementation strategy for keep-alives . . . . . . . . . . . 39 - 5.1. Keep-alives for SSH . . . . . . . . . . . . . . . . . . . 39 - 5.2. Keep-alives for TLS . . . . . . . . . . . . . . . . . . . 40 - - 6. Security Considerations . . . . . . . . . . . . . . . . . . . 40 - 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 41 - 8. Other Considerations . . . . . . . . . . . . . . . . . . . . 41 - 9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 42 - 10. References . . . . . . . . . . . . . . . . . . . . . . . . . 42 - 10.1. Normative References . . . . . . . . . . . . . . . . . . 42 - 10.2. Informative References . . . . . . . . . . . . . . . . . 43 - Appendix A. Examples . . . . . . . . . . . . . . . . . . . . . . 44 - A.1. NETCONF Configuration using SSH Transport . . . . . . . . 44 - A.2. NETCONF Configuration using TLS Transport . . . . . . . . 45 - A.3. RESTCONF Configuration using TLS Transport . . . . . . . 47 - Appendix B. Change Log . . . . . . . . . . . . . . . . . . . . . 47 - B.1. 00 to 01 . . . . . . . . . . . . . . . . . . . . . . . . 47 - B.2. 01 to 02 . . . . . . . . . . . . . . . . . . . . . . . . 48 - B.3. 02 to 03 . . . . . . . . . . . . . . . . . . . . . . . . 48 - B.4. 03 to 04 . . . . . . . . . . . . . . . . . . . . . . . . 48 - B.5. 04 to 05 . . . . . . . . . . . . . . . . . . . . . . . . 48 - B.6. 05 to 06 . . . . . . . . . . . . . . . . . . . . . . . . 49 - Appendix C. Open Issues . . . . . . . . . . . . . . . . . . . . 49 + 2.6.7. Customizations for periodic connections . . . . . . . 8 + 3. The NETCONF Server Model . . . . . . . . . . . . . . . . . . 8 + 3.1. Tree Diagram . . . . . . . . . . . . . . . . . . . . . . 8 + 3.2. Example Usage . . . . . . . . . . . . . . . . . . . . . . 9 + 3.2.1. Configuring SSH Transport . . . . . . . . . . . . . . 10 + 3.2.2. Configuring TLS Transport . . . . . . . . . . . . . . 11 + 3.3. YANG Model . . . . . . . . . . . . . . . . . . . . . . . 13 + 4. The RESTCONF Server Model . . . . . . . . . . . . . . . . . . 26 + 4.1. Tree Diagram . . . . . . . . . . . . . . . . . . . . . . 26 + 4.2. Example Usage . . . . . . . . . . . . . . . . . . . . . . 27 + 4.2.1. Configuring TLS Transport . . . . . . . . . . . . . . 27 + 4.3. YANG Model . . . . . . . . . . . . . . . . . . . . . . . 28 + 5. Security Considerations . . . . . . . . . . . . . . . . . . . 37 + 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 38 + 7. Other Considerations . . . . . . . . . . . . . . . . . . . . 39 + 8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 39 + 9. References . . . . . . . . . . . . . . . . . . . . . . . . . 39 + 9.1. Normative References . . . . . . . . . . . . . . . . . . 39 + 9.2. Informative References . . . . . . . . . . . . . . . . . 40 + Appendix A. Alternative solution addressing Issue #49 . . . . . 41 + A.1. The Keychain Model . . . . . . . . . . . . . . . . . . . 41 + A.1.1. Tree Diagram . . . . . . . . . . . . . . . . . . . . 41 + A.1.2. Example Usage . . . . . . . . . . . . . . . . . . . . 42 + A.1.3. YANG Model . . . . . . . . . . . . . . . . . . . . . 45 + A.2. The SSH Server Model . . . . . . . . . . . . . . . . . . 52 + A.2.1. Tree Diagram . . . . . . . . . . . . . . . . . . . . 52 + A.2.2. Example Usage . . . . . . . . . . . . . . . . . . . . 53 + A.2.3. YANG Model . . . . . . . . . . . . . . . . . . . . . 53 + A.3. The TLS Server Model . . . . . . . . . . . . . . . . . . 56 + A.3.1. Tree Diagram . . . . . . . . . . . . . . . . . . . . 56 + A.3.2. Example Usage . . . . . . . . . . . . . . . . . . . . 57 + A.3.3. YANG Model . . . . . . . . . . . . . . . . . . . . . 57 + A.4. The NETCONF Server Model . . . . . . . . . . . . . . . . 60 + A.4.1. Tree Diagram . . . . . . . . . . . . . . . . . . . . 60 + A.4.2. Example Usage . . . . . . . . . . . . . . . . . . . . 62 + A.4.3. YANG Model . . . . . . . . . . . . . . . . . . . . . 64 + A.5. The RESTCONF Server Model . . . . . . . . . . . . . . . . 75 + A.5.1. Tree Diagram . . . . . . . . . . . . . . . . . . . . 75 + A.5.2. Example Usage . . . . . . . . . . . . . . . . . . . . 76 + A.5.3. YANG Model . . . . . . . . . . . . . . . . . . . . . 76 + Appendix B. Change Log . . . . . . . . . . . . . . . . . . . . . 84 + B.1. 00 to 01 . . . . . . . . . . . . . . . . . . . . . . . . 84 + B.2. 01 to 02 . . . . . . . . . . . . . . . . . . . . . . . . 84 + B.3. 02 to 03 . . . . . . . . . . . . . . . . . . . . . . . . 84 + B.4. 03 to 04 . . . . . . . . . . . . . . . . . . . . . . . . 84 + B.5. 04 to 05 . . . . . . . . . . . . . . . . . . . . . . . . 85 + B.6. 05 to 06 . . . . . . . . . . . . . . . . . . . . . . . . 85 + B.7. 06 to 07 . . . . . . . . . . . . . . . . . . . . . . . . 86 + Appendix C. Open Issues . . . . . . . . . . . . . . . . . . . . 87 1. Introduction This draft defines a NETCONF [RFC6241] server configuration data model and a RESTCONF [draft-ietf-netconf-restconf] server configuration data model. These data models enable configuration of the NETCONF and RESTCONF services themselves, including which - transports are supported, what ports the servers listens on, whether - call-home is supported, and associated parameters. + transports are supported, what ports the servers listen on, call-home + parameters, client authentication, and other related configuration + 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 the data models is used in @@ -203,23 +211,22 @@ 2. Objectives The primary purpose of the YANG modules defined herein is to enable the configuration of the NETCONF and RESTCONF services on a network element. This scope includes the following objectives: 2.1. Support all NETCONF and RESTCONF transports The YANG module should support all current NETCONF and RESTCONF transports, namely NETCONF over SSH [RFC6242], NETCONF over TLS - [draft-ietf-netconf-rfc5539bis], and RESTCONF over TLS - [draft-ietf-netconf-restconf], and to be extensible to support future - transports as necessary. + [RFC7589], and RESTCONF over TLS [draft-ietf-netconf-restconf], and + to be extensible to support future transports as necessary. Because 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. Enable each transport to select which keys to use 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 @@ -232,296 +239,387 @@ When a certificate is used to authenticate a NETCONF or RESTCONF 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. 2.4. Support mapping authenticated NETCONF/RESTCONF client certificates to usernames - When a client certifcate is used for TLS transport-level - authentication, the NETCONF/RESTCONF server must be able to derive a - username from the authenticated certifcate. Thus the modules defined - herein should enable this mapping to be configured. + When a client certificate is used for TLS client authentication, the + NETCONF/RESTCONF server must be able to derive a username from the + authenticated certificate. Thus the modules defined herein should + enable this mapping to be configured. -2.5. Support both Listening for connections and Call Home +2.5. Support both listening for connections and call home The NETCONF and RESTCONF 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 ([draft-ietf-netconf-call-home]), enabling the server to initiate the connection to the client, for both the NETCONF and RESTCONF protocols. 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. 2.6. For Call Home connections The following objectives only pertain to call home connections. -2.6.1. Support more than one northbound application +2.6.1. Support more than one NETCONF/RESTCONF client - 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 - to more than one application. + A NETCONF/RESTCONF server may be managed by more than one NETCONF/ + RESTCONF 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. -2.6.2. Support applications having more than one server +2.6.2. Support NETCONF/RESTCONF clients having more than one endpoint - 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 the application's - servers. + An NETCONF/RESTCONF client managing a NETCONF/RESTCONF 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. 2.6.3. Support a reconnection 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. + Assuming a NETCONF/RESTCONF client has more than one endpoint, then + it becomes necessary to configure how a NETCONF/RESTCONF server + should reconnect to the client should it lose its connection to one + the client's endpoints. For instance, the NETCONF/RESTCONF server + may start with first endpoint defined in a user-ordered list of + endpoints or with thei last endpoints it was connected to. 2.6.4. Support both persistent and periodic 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 prefer periodic interactions in - order to minimize resource requirements. Therefore, when it is - necessary for devices to initiate connections, the type of connection - desired should be configurable. + NETCONF/RESTCONF clients may vary greatly on how frequently they need + to interact with a NETCONF/RESTCONF 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. 2.6.5. Reconnection strategy for periodic 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. 2.6.6. Keep-alives for persistent connections 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 - application requirements, and therefore keep-alive settings should be - configurable on a per-application basis. + NETCONF/RESTCONF client requirements, and therefore keep-alive + settings should be configurable on a per-client basis. 2.6.7. Customizations for periodic 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. The NETCONF Server Configuration Model + If a periodic connection is desired, it is necessary for the NETCONF/ + RESTCONF server to know how often it should connect. This frequency + determines the maximum amount of time a NETCONF/RESTCONF 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). -3.1. Overview +3. The NETCONF Server Model -3.1.1. The "session-options" subtree +3.1. Tree Diagram module: ietf-netconf-server +--rw netconf-server +--rw session-options - +--rw hello-timeout? uint32 - +--rw idle-timeout? uint32 - - The above subtree illustrates how the ietf-netconf-server YANG module - enables configuration of NETCONF session options, independent of any - transport or connection strategy. Please see the YANG module - (Section 3.2) for a complete description of these configuration - knobs. - -3.1.2. The "listen" subtree - module: ietf-netconf-server - +--rw netconf-server - +--rw listen {listen}? - +--rw max-sessions? uint16 - +--rw endpoint* [name] - +--rw name string - +--rw (transport) - | +--:(ssh) {ssh}? + | +--rw hello-timeout? uint16 + +--rw listen {(ssh-listen or tls-listen)}? + | +--rw max-sessions? uint16 + | +--rw idle-timeout? uint16 + | +--rw endpoint* [name] + | +--rw name string + | +--rw (transport) + | +--:(ssh) {ssh-listen}? | | +--rw ssh | | +--rw address? inet:ip-address | | +--rw port? inet:port-number | | +--rw host-keys | | +--rw host-key* string - | +--:(tls) {tls}? + | +--:(tls) {tls-listen}? | +--rw tls | +--rw address? inet:ip-address | +--rw port? inet:port-number | +--rw certificates | +--rw certificate* string - +--rw keep-alives - +--rw interval-secs? uint8 - +--rw count-max? uint8 - - The above subtree illustrates how the ietf-netconf-server YANG module - enables configuration for listening for remote connections, as - described in [RFC6242]. 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 list of listening endpoints, each configured with a - user-specified name (the key field), the transport to use (i.e. SSH, - TLS), and the IP address and port to listen on. The port field is - optional, defaulting to the transport-specific port when not - configured. Please see the YANG module (Section 3.2) for a complete - description of these configuration knobs. - -3.1.3. The "call-home" subtree - module: ietf-netconf-server - +--rw netconf-server - +--rw call-home {call-home}? - +--rw application* [name] - +--rw name string - +--rw (transport) - | +--:(ssh) {ssh}? - | | +--rw ssh + +--rw call-home {(ssh-call-home or tls-call-home)}? + | +--rw netconf-client* [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 + | | | +--rw host-keys + | | | +--rw host-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 host-keys - | | +--rw host-key* string - | +--:(tls) {tls}? - | +--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 - - The above subtree illustrates how the ietf-netconf-server YANG module - enables configuration for call home, as described in - [draft-ietf-netconf-call-home]. Feature statements are used to limit - 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 to connect to. Each - application is configured with a user-specified name (the key field), - the transport to be 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. Please see - the YANG module (Section 3.2) for a complete description of these - configuration knobs. - -3.1.4. The "ssh" subtree - - module: ietf-netconf-server - +--rw netconf-server - +--rw ssh {ssh}? - +--rw x509 {ssh-x509-certs}? - +--rw trusted-ca-certs - | +--rw trusted-ca-cert* binary - +--rw trusted-client-certs - +--rw trusted-client-cert* binary - - The above subtree illustrates how the ietf-netconf-server YANG module - enables some SSH configuration independent of if the NETCONF server - is listening or calling home. Specifically, when RFC 6187 is - supported, this data model provides an ability to configure how - client-certificates are authenticated. Please see the YANG module - (Section 3.2) for a complete description of these configuration - knobs. - -3.1.5. The "tls" subtree - - module: ietf-netconf-server - +--rw netconf-server - +--rw tls {tls}? + | | +--rw certificates + | | +--rw certificate* string + | +--rw connection-type + | | +--rw (connection-type)? + | | +--:(persistent-connection) + | | | +--rw persistent! + | | | +--rw idle-timeout? uint32 + | | | +--rw keep-alives + | | | +--rw max-wait? uint16 + | | | +--rw max-attempts? uint8 + | | +--:(periodic-connection) + | | +--rw periodic! + | | +--rw idle-timeout? uint16 + | | +--rw reconnect_timeout? uint16 + | +--rw reconnect-strategy + | +--rw start-with? enumeration + | +--rw max-attempts? uint8 + +--rw ssh {(ssh-listen or ssh-call-home)}? + | +--rw x509 {ssh-x509-certs}? + | +--rw trusted-ca-certs + | | +--rw trusted-ca-cert* binary + | +--rw trusted-client-certs + | +--rw trusted-client-cert* binary + +--rw tls {(tls-listen or tls-call-home)}? +--rw client-auth +--rw trusted-ca-certs | +--rw trusted-ca-cert* binary +--rw trusted-client-certs | +--rw trusted-client-cert* binary +--rw cert-maps +--rw cert-to-name* [id] +--rw id uint32 +--rw fingerprint x509c2n:tls-fingerprint +--rw map-type identityref +--rw name string - The above subtree illustrates how the ietf-netconf-server YANG module - enables TLS configuration independent of if the NETCONF server is - listening or calling home. Specifically, this data-model provides 1) - an ability to configure how client-certificates are authenticated and - 2) how authenticated client-certificates are mapped to NETCONF user - names. Please see the YANG module (Section 3.2) for a complete - description of these configuration knobs. +3.2. Example Usage +3.2.1. Configuring SSH Transport -3.2. YANG Module + The following example illustrates the response from a NETCONF + server that only supports SSH, both listening for incoming + connections as well as calling home to a single NETCONF/RESTCONF + client having two endpoints. + + + + + netconf/ssh + +
11.22.33.44
+ + my-rsa-key + my-dss-key + + + + + + + config-mgr + + + + east-data-center +
11.22.33.44
+ + + west-data-center +
55.66.77.88
+ + + + my-call-home-x509-key + + + + + + + + + QW4gRWFzdGVyIGVnZywgZm9yIHRob3NlIHdobyBtaWdodCBsb29rICA6KQo= + + + + + SSBhbSB0aGUgZWdnIG1hbiwgdGhleSBhcmUgdGhlIGVnZyBtZW4uCg== + + + SSBhbSB0aGUgd2FscnVzLCBnb28gZ29vIGcnam9vYi4K + + + + + + +3.2.2. Configuring TLS Transport + + The following example illustrates the response from a NETCONF + server that only supports TLS, both listening for incoming + connections as well as calling home to a single NETCONF/RESTCONF + client having two endpoints. Please note also the configurations for + authenticating client certificates and mappings authenticated + certificates to NETCONF user names. + + + + + netconf/tls + +
11.22.33.44
+ + fw1.east.example.com + + + + + + + config-mgr + + + + east-data-center +
22.33.44.55
+ + + west-data-center +
33.44.55.66
+ + + + IDevID Certificate + + + + + + + + + WmdsK2gyTTg3QmtGMjhWbW1CdFFVaWc3OEgrRkYyRTFwdSt4ZVRJbVFFM + lLQllsdWpOcjFTMnRLR05EMUc2OVJpK2FWNGw2NTdZNCtadVJMZgpRYjk + zSFNwSDdwVXBCYnA4dmtNanFtZjJma3RqZHBxeFppUUtTbndWZTF2Zwot + NGcEk3UE90cnNFVjRwTUNBd0VBQWFPQ0FSSXdnZ0VPCk1CMEdBMVVkRGd + VEJiZ0JTWEdlbUEKMnhpRHVOTVkvVHFLNWd4cFJBZ1ZOYUU0cERZd05ER + V6QVJCZ05WQkFNVENrTlNUQ0JKYzNOMVpYS0NDUUNVRHBNSll6UG8zREF + NQmdOVkhSTUJBZjhFCkFqQUFNQTRHQTFVZER3RUIvd1FFQXdJSGdEQnBC + Z05WSFI4RVlqQmdNRjZnSXFBZ2hoNW9kSFJ3T2k4dlpYaGgKYlhCc1pTN + WpiMjB2WlhoaGJYQnNaUzVqY215aU9LUTJNRFF4Q3pBSkJnTlZCQVlUQW + QmdOVkJBWVRBbFZUTVJBd0RnWURWUVFLRXdkbAplR0Z0Y0d4bE1RNHdEQ + MkF6a3hqUDlVQWtHR0dvS1U1eUc1SVR0Wm0vK3B0R2FieXVDMjBRd2kvZ + 25PZnpZNEhONApXY0pTaUpZK2xtYWs3RTRORUZXZS9RdGp4NUlXZmdvN2 + RJSUJQFRStS0Cg== + + + + + QmdOVkJBWVRBbFZUTVJBd0RnWURWUVFLRXdkbAplR0Z0Y0d4bE1RNHdEQ + MkF6a3hqUDlVQWtHR0dvS1U1eUc1SVR0Wm0vK3B0R2FieXVDMjBRd2kvZ + 25PZnpZNEhONApXY0pTaUpZK2xtYWs3RTRORUZXZS9RdGp4NUlXZmdvN2 + RV0JCU2t2MXI2SFNHeUFUVkpwSmYyOWtXbUU0NEo5akJrQmdOVkhTTUVY + VEJiZ0JTWEdlbUEKMnhpRHVOTVkvVHFLNWd4cFJBZ1ZOYUU0cERZd05ER + UxNQWtHQTFVRUJoTUNWVk14RURBT0JnTlZCQW9UQjJWNApZVzF3YkdVeE + V6QVJCZ05WQkFNVENrTlNUQ0JKYzNOMVpYS0NDUUNVRHBNSll6UG8zREF + NQmdOVkhSTUJBZjhFCkFqQUFNQTRHQTFVZER3RUIvd1FFQXdJSGdEQnBC + Z05WSFI4RVlqQmdNRjZnSXFBZ2hoNW9kSFJ3T2k4dlpYaGgKYlhCc1pTN + WpiMjB2WlhoaGJYQnNaUzVqY215aU9LUTJNRFF4Q3pBSkJnTlZCQVlUQW + xWVE1SQXdEZ1lEVlFRSwpFd2RsZUdGdGNHeGxNUk13RVFZRFZRUURFd3B + EVWt3Z1NYTnpkV1Z5TUEwR0NTcUdTSWIzRFFFQkJRVUFBNEdCCkFFc3BK + WmdsK2gyTTg3QmtGMjhWbW1CdFFVaWc3OEgrRkYyRTFwdSt4ZVRJbVFFM + TQzcjFZSjk0M1FQLzV5eGUKN2QxMkxCV0dxUjUrbEl5N01YL21ka2M4al + zSFNwSDdwVXBCYnA4dmtNanFtZjJma3RqZHBxeFppUUtTbndWZTF2Zwot + LS0tLUVORCBDRVJUSUZJQ0FURS0tLS0tCg== + + + VlEVlFRREV3Vm9ZWEJ3ZVRDQm56QU5CZ2txaGtpRzl3MEJBUUVGQUFPQm + pRQXdnWWtDCmdZRUE1RzRFSWZsS1p2bDlXTW44eUhyM2hObUFRaUhVUzV + rRUpPQy9hSFA3eGJXQW1ra054ZStUa2hrZnBsL3UKbVhsTjhSZUd1ODhG + NGcEk3UE90cnNFVjRwTUNBd0VBQWFPQ0FSSXdnZ0VPCk1CMEdBMVVkRGd + VEJiZ0JTWEdlbUEKMnhpRHVOTVkvVHFLNWd4cFJBZ1ZOYUU0cERZd05ER + V6QVJCZ05WQkFNVENrTlNUQ0JKYzNOMVpYS0NDUUNVRHBNSll6UG8zREF + NQmdOVkhSTUJBZjhFCkFqQUFNQTRHQTFVZER3RUIvd1FFQXdJSGdEQnBC + Z05WSFI4RVlqQmdNRjZnSXFBZ2hoNW9kSFJ3T2k4dlpYaGgKYlhCc1pTN + WpiMjB2WlhoaGJYQnNaUzVqY215aU9LUTJNRFF4Q3pBSkJnTlZCQVlUQW + xWVE1SQXdEZ1lEVlFRSwpFd2RsZUdGdGNHeGxNUk13RVFZRFZRUURFd3B + EVWt3Z1NYTnpkV1Z5TUEwR0NTcUdTSWIzRFFFQkJRVUFBNEdCCkFFc3BK + WmdsK2gyTTg3QmtGMjhWbW1CdFFVaWc3OEgrRkYyRTFwdSt4ZVRJbVFFM + lLQllsdWpOcjFTMnRLR05EMUc2OVJpK2FWNGw2NTdZNCtadVJMZgpRYjk + zSFNwSDdwVXBCYnA4dmtNanFtZjJma3RqZHBxeFppUUtTbndWZTF2Zwot + QWtUOCBDRVUUZJ0RUF== + + + + + 1 + 11:0A:05:11:00 + x509c2n:san-any + + + 2 + B3:4F:A1:8C:54 + x509c2n:specified + scooby-doo + + + + + + +3.3. YANG Model This YANG module imports YANG types from [RFC6991] and [RFC7407]. - file "ietf-netconf-server@2015-02-02.yang" + file "ietf-netconf-server@2015-07-06.yang" module ietf-netconf-server { + yang-version 1.1; namespace "urn:ietf:params:xml:ns:yang:ietf-netconf-server"; prefix "ncserver"; import ietf-netconf-acm { prefix nacm; // RFC 6536 - revision-date 2012-02-22; } import ietf-inet-types { // RFC 6991 prefix inet; - revision-date 2013-07-15; } import ietf-x509-cert-to-name { // RFC 7407 prefix x509c2n; - revision-date 2014-12-10; } organization "IETF NETCONF (Network Configuration) Working Group"; contact "WG Web: WG List: WG Chair: Mehmet Ersue @@ -543,57 +641,63 @@ 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 VVVV; see the RFC itself for full legal notices."; - revision "2015-02-02" { + revision "2015-07-06" { description "Initial version"; reference - "RFC VVVV: NETCONF Server and RESTCONF Server Configuration Models"; + "RFC VVVV: NETCONF Server and RESTCONF Server Configuration + Models"; } - // Features - feature ssh { + feature ssh-listen { description - "The ssh feature indicates that the server supports the - SSH transport protocol."; + "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 { + feature ssh-call-home { description - "The tls feature indicates that the server supports the - TLS transport protocol."; + "The ssh-call-home feature indicates that the NETCONF + server supports initiating a NETCONF over SSH call + home connection to NETCONF clients."; reference - "RFC 5539: NETCONF over Transport Layer Security (TLS)"; + "RFC YYYY: NETCONF Call Home and RESTCONF Call Home"; } - feature listen { + feature tls-listen { description - "The listen feature indicates that the server supports - opening a port to listen for incoming client connections."; + "The tls-listen feature indicates that the NETCONF server + supports opening a port to accept NETCONF over TLS + client connections."; reference - "RFC 6242: Using the NETCONF Protocol over Secure Shell (SSH) - RFC 5539: NETCONF over Transport Layer Security (TLS)"; + "RFC 5539: Using the NETCONF Protocol over Transport + Layer Security (TLS) with Mutual X.509 + Authentication"; } - feature call-home { + + feature tls-call-home { description - "The call-home feature indicates that the server supports - connecting to the client"; + "The tls-call-home feature indicates that the NETCONF + server supports initiating a NETCONF over TLS call + home connection to NETCONF clients."; reference "RFC YYYY: NETCONF Call Home and RESTCONF Call Home"; } feature ssh-x509-certs { description "The ssh-x509-certs feature indicates that the NETCONF server supports RFC 6187"; reference "RFC 6187: X.509v3 Certificates for Secure Shell Authentication"; @@ -591,386 +695,369 @@ "RFC YYYY: NETCONF Call Home and RESTCONF Call Home"; } feature ssh-x509-certs { description "The ssh-x509-certs feature indicates that the NETCONF server supports RFC 6187"; reference "RFC 6187: X.509v3 Certificates for Secure Shell Authentication"; } - // top-level container (groupings below) container netconf-server { description "Top-level container for NETCONF server configuration."; - uses session-options-container; - uses listen-container; - uses call-home-container; - uses ssh-container; - uses tls-container; - - } - - grouping session-options-container { - description - "This grouping is used only to help improve readability - of the YANG module."; - container session-options { + container session-options { // SHOULD WE REMOVE THIS ALTOGETHER? 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 may be supported by the server."; - } - leaf idle-timeout { - type uint32 { - range "0 | 10 .. 360000"; - } + type uint16; units "seconds"; - default '3600'; + default 600; description - "Specifies the number of seconds that a NETCONF 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. If this parameter is 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. - - This mechanism is independent of keep-alives, as it regards - activity occurring at the NETCONF protocol layer, whereas - the keep-alive mechanism regards transport-level activity."; - } + "Specifies the maximum number of seconds that a SSH/TLS + connection may wait for a hello message to be received. + A connection will be dropped if no hello message is + received before this number of seconds elapses. If set + to zero, then the server will wait forever for a hello + message."; } } - grouping listen-container { - description - "This grouping is used only to help improve readability - of the YANG module."; container listen { description "Configures listen behavior"; - if-feature listen; + if-feature "(ssh-listen or tls-listen)"; leaf max-sessions { - type uint16 { - range "0 .. 1024"; - } - default '0'; + type uint16; + 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."; } + 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; description "List of endpoints to listen for NETCONF connections on."; leaf name { type string; description "An arbitrary name for the NETCONF listen endpoint."; } choice transport { mandatory true; description - "Selects between SSH and TLS transports."; + "Selects between available transports."; case ssh { - if-feature ssh; + if-feature ssh-listen; container ssh { description "SSH-specific listening configuration for inbound connections."; uses address-and-port-grouping { refine port { default 830; } } - uses host-keys-container; + uses host-keys-grouping; } } case tls { - if-feature tls; + if-feature tls-listen; container tls { description "TLS-specific listening configuration for inbound connections."; uses address-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 + uses certificates-grouping; } } } } } - grouping call-home-container { - description - "This grouping is used only to help improve readability - of the YANG module."; container call-home { - if-feature call-home; + if-feature "(ssh-call-home or tls-call-home)"; description "Configures call-home behavior"; - list application { + + list netconf-client { key name; description "List of NETCONF clients the NETCONF server is to initiate call-home connections to."; leaf name { type string; description "An arbitrary name for the remote NETCONF client."; } choice transport { mandatory true; description "Selects between available transports."; case ssh { - if-feature ssh; + if-feature ssh-call-home; container ssh { description "Specifies SSH-specific call-home transport configuration."; uses endpoints-container { refine endpoints/endpoint/port { default 7777; } } - uses host-keys-container; + uses host-keys-grouping; } } case tls { - if-feature tls; + if-feature tls-call-home; container tls { description "Specifies TLS-specific call-home transport configuration."; uses endpoints-container { refine endpoints/endpoint/port { default 8888; } } - uses certificates-container; + uses certificates-grouping; } } } container connection-type { description "Indicates the kind of connection to use."; choice connection-type { - default persistent-connection; description - "Selects between persistent and periodic connections."; + "Selects between available connection types."; case persistent-connection { container persistent { + presence true; 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."; - uses keep-alives-container { - refine keep-alives/interval-secs { - default 15; // 15 seconds for call-home sessions + leaf idle-timeout { + type uint32; + units "seconds"; + default 86400; // one day; + description + "Specifies the maximum number of seconds that a + 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."; + } + container keep-alives { + description + "Configures the keep-alive policy, to proactively + test the aliveness of the SSH/TLS client. An + unresponsive SSH/TLS client will be dropped after + approximately (max-attempts * max-wait) seconds."; + reference + "RFC YYYY: NETCONF Call Home and RESTCONF Call Home, + Section 3.1, item S6"; + leaf max-wait { + type uint16 { + range "1..max"; + } + units seconds; + default 30; + description + "Sets the amount of time in seconds after which + if no data has been received from the SSH/TLS + client, a SSH/TLS-level message will be sent + to test the aliveness of the SSH/TLS client."; + } + leaf max-attempts { + type uint8; + default 3; + description + "Sets the number of sequential keep-alive messages + that can fail to obtain a response from the SSH/TLS + client before assuming the SSH/TLS client is no + longer alive."; } } } } case periodic-connection { container periodic { + presence true; description - "Periodically connect to NETCONF client, using the - reconnection strategy, so the NETCONF client can - deliver pending messages to the NETCONF server. - - For messages the NETCONF server wants to send to - to the NETCONF client, the NETCONF server should - proactively connect to the NETCONF client, if - not already, to send the messages immediately."; - leaf timeout-mins { - type uint8; - units minutes; - default 5; + "Periodically connect to the NETCONF client, so that + the NETCONF client may deliver messages pending for + the NETCONF server. The NETCONF client is expected + to close the connection when it is ready to release + it, thus starting the NETCONF server's timer until + next connection."; + leaf idle-timeout { + type uint16; + units "seconds"; + default 300; // five minutes description - "The maximum amount of unconnected time the NETCONF - server will wait until establishing a connection to - the NETCONF client again. The NETCONF server MAY - establish a connection before this time if it has - data it needs to send to the NETCONF client. Note: - this value differs from the reconnection strategy's - interval-secs value."; + "Specifies the maximum number of seconds that a + 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."; } - leaf linger-secs { - type uint8; - units seconds; - default 30; + leaf reconnect_timeout { + type uint16 { + range "1..max"; + } + units minutes; + default 60; description - "The amount of time the NETCONF server should wait - after last receiving data from or sending data to - the NETCONF client's endpoint before closing its - connection to it. This is an optimization to - prevent unnecessary connections."; + "The maximum amount of unconnected time the NETCONF + server will wait before establishing a connection + to the NETCONF client. The NETCONF server may + initiate a connection before this time if desired + (e.g., to deliver a notification)."; + } } } } } container reconnect-strategy { description "The reconnection strategy guides how a NETCONF server reconnects to an NETCONF client, after losing a connection to it, even if due to a reboot. The NETCONF server starts with the specified endpoint and 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)."; + 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. NETCONF servers - SHOULD support this flag across reboots."; + 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."; } - } 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. If no previous connection has - ever been established, last-connected defaults to - the first endpoint listed."; + to the NETCONF client."; } - 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 max-attempts { + type uint8 { + range "1..max"; } - leaf count-max { - type uint8; 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)."; } } } - } + } - grouping ssh-container { - description - "This grouping is used only to help improve readability - of the YANG module."; container ssh { description "Configures SSH properties not specific to the listen or call-home use-cases"; - if-feature ssh; + if-feature "(ssh-listen or ssh-call-home)"; container x509 { if-feature ssh-x509-certs; uses trusted-certs-grouping; } } - } - grouping tls-container { - description - "This grouping is used only to help improve readability - of the YANG module."; + container tls { description "Configures TLS properties for authenticating clients."; - if-feature tls; + if-feature "(tls-listen or tls-call-home)"; container client-auth { description "Container for TLS client authentication configuration."; uses trusted-certs-grouping; container cert-maps { 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."; + reference + "RFC WWWW: NETCONF over TLS, Section 7"; } } } } grouping trusted-certs-grouping { description "This grouping is used by both the ssh and tls containers."; 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. 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."; + certificates."; + reference + "RFC WWWW: NETCONF over TLS, Sections 5 and 7. + RFC 4253: The Secure Shell (SSH) Transport Layer Protocol, + Section 8, #3. + RFC 6187: X.509v3 Certificates for Secure Shell + Authentication."; leaf-list trusted-ca-cert { type binary; - ordered-by system; nacm:default-deny-write; 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"; } } 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 @@ -967,40 +1054,39 @@ reference "RFC 5246: The Transport Layer Security (TLS) Protocol Version 1.2"; } } 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."; + match to a configured trusted client certificate."; leaf-list trusted-client-cert { type binary; - ordered-by system; nacm:default-deny-write; 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 host-keys-container { + grouping host-keys-grouping { description "This grouping is used by both the listen and call-home containers"; container host-keys { description "Parent container for the list of host-keys."; leaf-list host-key { type string; min-elements 1; ordered-by user; @@ -1013,21 +1099,21 @@ on the system. How valid values are discovered is outside the scope of this module, but they are envisioned to be the keys for a list of host-keys provided by another YANG module"; reference "RFC 4253: The SSH Transport Layer Protocol, Section 7"; } } } - grouping certificates-container { + grouping certificates-grouping { description "This grouping is used by both the listen and call-home containers"; container certificates { description "Parent container for the list of certificates."; leaf-list certificate { type string; min-elements 1; description @@ -1039,34 +1125,38 @@ to be the keys for a list of certificates provided by another YANG module"; reference "RFC 5246: The TLS Protocol, Section 7.4.2"; } } } grouping address-and-port-grouping { description - "This grouping is usd by both the ssh and tls containers + "This grouping is used by both the ssh and tls containers for listen configuration."; leaf address { type inet:ip-address; description - "The IP address of the interface to listen on."; + "The IP address of the interface to listen on. The NETCONF + server will listen on all interfaces if no value is + specified."; } leaf port { type inet:port-number; description "The local port number on this interface the NETCONF server - listens on."; + listens on. The NETCONF server will use the IANA-assigned + well-known port if no value is specified."; } } + grouping endpoints-container { description "This grouping is used by both the ssh and tls containers for call-home configurations."; container endpoints { description "Container for the list of endpoints."; list endpoint { key name; min-elements 1; @@ -1070,210 +1160,167 @@ list endpoint { key name; min-elements 1; ordered-by user; description "User-ordered list of endpoints for this NETCONF client. Defining more than one enables high-availability."; leaf name { type string; description - "An arbitrary name for the endpoint to connect to."; + "An arbitrary name for this endpoint."; } leaf address { type inet:host; mandatory true; description - "The hostname or IP address or hostname of the endpoint. - If a hostname is provided and DNS resolves to more than - one IP address, the NETCONF server SHOULD try all of - the ones it can based on how its networking stack is - configured (e.g. v4, v6, dual-stack)."; + "The IP address or hostname of the endpoint. If a + hostname is configured and the DNS resolution results + in more than one IP address, the NETCONF server + will process the IP addresses as if they had been + explicitly configured in place of the hostname."; } leaf port { type inet:port-number; description "The IP port for this endpoint. The NETCONF server will - use the IANA-assigned well-known port if not specified."; + use the IANA-assigned well-known port if no value is + specified."; } } } } - grouping keep-alives-container { - description - "This grouping is use by both listen and call-home configurations."; - container keep-alives { - description - "Configures the keep-alive policy, to proactively test the - aliveness of the NETCONF client."; - reference - "RFC VVVV: NETCONF Server and RESTCONF Server Configuration - Models, Section 4"; - leaf interval-secs { - type uint8; - units seconds; - description - "Sets a timeout interval in seconds after which if no data - has been received from the NETCONF 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."; - } - 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 NETCONF client before - assuming the NETCONF client is no longer alive. If this - threshold is reached, the transport-level connection will - be disconnected, which will trigger the reconnection - strategy). The interval timer is reset after each - transmission, thus an unresponsive NETCONF client will - be dropped after approximately (count-max * interval-secs) - seconds."; - } - } - } } -4. The RESTCONF Server Configuration Model +4. The RESTCONF Server Model -4.1. Overview +4.1. Tree Diagram -4.1.1. The "listen" subtree module: ietf-restconf-server +--rw restconf-server - +--rw listen {listen}? - +--rw max-sessions? uint16 - +--rw endpoint* [name] - +--rw name string - +--rw (transport) + +--rw listen {tls-listen}? + | +--rw max-sessions? uint16 + | +--rw endpoint* [name] + | +--rw name string + | +--rw (transport) | +--:(tls) | +--rw tls | +--rw address? inet:ip-address | +--rw port? inet:port-number | +--rw certificates | +--rw certificate* string - +--rw keep-alives - +--rw interval-secs? uint8 - +--rw count-max? uint8 - - The above subtree illustrates how the ietf-restconf-server YANG - module enables configuration for listening for remote connections, as - described in [draft-ietf-netconf-restconf]. 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 list of listening endpoints, each - configured with a user-specified name (the key field), the transport - to use (i.e. TLS), and the IP address and port to listen on. The - port field is optional, defaulting to the transport-specific port - when not configured. Please see the YANG module (Section 4.2) for a - complete description of these configuration knobs. - -4.1.2. The "call-home" subtree - module: ietf-restconf-server - +--rw restconf-server - +--rw call-home {call-home}? - +--rw application* [name] - +--rw name string - +--rw (transport) - | +--:(tls) {tls}? - | +--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 - - The above subtree illustrates how the ietf-restconf-server YANG - module enables configuration for call home, as described in - [draft-ietf-netconf-call-home]. Feature statements are used to limit - 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 to connect to. Each - application is configured with a user-specified name (the key field), - the transport to be used (i.e. 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. Please see - the YANG module (Section 4.2) for a complete description of these - configuration knobs. - -4.1.3. The "client-cert-auth" subtree - - module: ietf-restconf-server - +--rw restconf-server + +--rw call-home {tls-call-home}? + | +--rw restconf-client* [name] + | +--rw name string + | +--rw (transport) + | | +--:(tls) + | | +--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 max-wait? uint16 + | | | +--rw max-attempts? uint8 + | | +--:(periodic-connection) + | | +--rw periodic! + | | +--rw reconnect-timeout? uint16 + | +--rw reconnect-strategy + | +--rw start-with? enumeration + | +--rw max-attempts? uint8 +--rw client-cert-auth {client-cert-auth}? +--rw trusted-ca-certs | +--rw trusted-ca-cert* binary +--rw trusted-client-certs | +--rw trusted-client-cert* binary +--rw cert-maps +--rw cert-to-name* [id] +--rw id uint32 +--rw fingerprint x509c2n:tls-fingerprint +--rw map-type identityref +--rw name string - The above subtree illustrates how the ietf-restconf-server YANG - module enables configuration of client-certificate authentication. - Specifically, this data-model provides 1) an ability to configure how - client-certificates are authenticated and 2) how authenticated - client-certificates are mapped to RESTCONF user names. Please see - the YANG module (Section 4.2) for a complete description of these - configuration knobs. +4.2. Example Usage -4.2. YANG Module +4.2.1. Configuring TLS Transport + + The following example illustrates the response from a RESTCONF + server that only supports TLS, both listening for incoming + connections as well as calling home to a single RESTCONF client + having two endpoints. + + + + + primary-restconf-endpoint + +
11.22.33.44
+ + fw1.east.example.com + + + + + + + config-mgr + + + + east-data-center +
11.22.33.44
+ + + west-data-center +
55.66.77.88
+ + + + fw1.east.example.com + + + + + + +4.3. YANG Model This YANG module imports YANG types from [RFC6991] and [RFC7407]. - file "ietf-restconf-server@2015-02-02.yang" + file "ietf-restconf-server@2015-07-06.yang" module ietf-restconf-server { + yang-version 1.1; namespace "urn:ietf:params:xml:ns:yang:ietf-restconf-server"; prefix "rcserver"; import ietf-netconf-acm { prefix nacm; // RFC 6536 - revision-date 2012-02-22; } import ietf-inet-types { // RFC 6991 prefix inet; - revision-date 2013-07-15; } import ietf-x509-cert-to-name { // RFC 7407 prefix x509c2n; - revision-date 2014-12-10; } + organization "IETF NETCONF (Network Configuration) Working Group"; contact "WG Web: WG List: WG Chair: Mehmet Ersue @@ -1293,89 +1340,72 @@ 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 VVVV; see the RFC itself for full legal notices."; - revision "2015-02-02" { + revision "2015-07-06" { description "Initial version"; reference - "RFC VVVV: NETCONF Server and RESTCONF Server Configuration Models"; + "RFC VVVV: NETCONF Server and RESTCONF Server Configuration + Models"; } // Features - feature tls { - description - "The tls feature indicates that the server supports RESTCONF - over the TLS transport protocol."; - - reference - "RFC XXXX: RESTCONF Protocol"; - } - - feature listen { + feature tls-listen { description - "The listen feature indicates that the server supports - opening a port to listen for incoming client connections."; + "The listen feature indicates that the RESTCONF server + supports opening a port to listen for incoming RESTCONF + client connections."; reference "RFC XXXX: RESTCONF Protocol"; } - feature call-home { + feature tls-call-home { description - "The call-home feature indicates that the server supports - connecting to the client."; + "The call-home feature indicates that the RESTCONF server + supports initiating connections to RESTCONF clients."; reference "RFC YYYY: NETCONF Call Home and RESTCONF Call Home"; } feature client-cert-auth { description - "The client-cert-auth feature indicatres that the server - supports the ClientCertificate authentication scheme."; + "The client-cert-auth feature indicates that the RESTCONF + server supports the ClientCertificate authentication scheme."; reference "RFC ZZZZ: Client Authentication over New TLS Connection"; } // top-level container (groupings below) container restconf-server { description "Top-level container for RESTCONF server configuration."; - uses listen-container; - uses call-home-container; - uses client-cert-auth-container; - } - - grouping listen-container { - description - "This grouping is used only to help improve readability - of the YANG module."; container listen { description "Configures listen behavior"; - if-feature listen; + if-feature tls-listen; leaf max-sessions { - type uint16 { - range "0 .. 1024"; - } - default '0'; + type uint16; + default 0; // should this be 'max'? 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 RESTCONF connections on."; leaf name { type string; description "An arbitrary name for the RESTCONF listen endpoint."; } @@ -1381,137 +1411,181 @@ } choice transport { mandatory true; description "Selects between available transports."; case tls { container tls { description "TLS-specific listening configuration for inbound connections."; - uses address-and-port-grouping { - refine port { - default 443; - } - } - uses certificates-container; - } + leaf address { + type inet:ip-address; + description + "The IP address of the interface to listen on. The + RESTCONF server will listen on all interfaces if + no value is specified."; } + leaf port { + type inet:port-number; + default 443; + description + "The port number the RESTCONF server will listen on."; } - uses keep-alives-container { - refine keep-alives/interval-secs { - default 0; // disabled by default for listen connections + uses certificates-grouping; } } } } } - grouping call-home-container { - description - "This grouping is used only to help improve readability - of the YANG module."; container call-home { - if-feature call-home; + if-feature tls-call-home; description "Configures call-home behavior"; - list application { + list restconf-client { key name; description - "List of RESTCONF clients the RESTCONF server is to initiate - call-home connections to."; + "List of RESTCONF clients the RESTCONF server is to + initiate call-home connections to."; + leaf name { type string; description "An arbitrary name for the remote RESTCONF client."; } choice transport { mandatory true; description - "Selects between TLS and any future transports augmented in."; + "Selects between TLS and any transports augmented in."; case tls { - if-feature tls; container tls { description "Specifies TLS-specific call-home transport configuration."; - uses endpoints-container { - refine endpoints/endpoint/port { + 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 RESTCONF + client. More than one enables high-availability."; + leaf name { + type string; + description + "An arbitrary name for this endpoint."; + } + leaf address { + type inet:host; + mandatory true; + description + "The IP address or hostname of the endpoint. If + a hostname is configured and the DNS resolution + results in more than one IP address, the RESTCONF + server will process the IP addresses as if they + had been explicitly configured in place of the + hostname."; + } + leaf port { + type inet:port-number; default 9999; + description + "The IP port for this endpoint. The RESTCONF + server will use the IANA-assigned well-known + port if no value is specified."; } + } - uses certificates-container; + } + uses certificates-grouping; } } } container connection-type { description "Indicates the RESTCONF client's preference for how the RESTCONF server's connection is maintained."; choice connection-type { - default persistent-connection; description - "Selects between persistent and periodic connections."; + "Selects between available connection types."; case persistent-connection { container persistent { + presence true; description "Maintain a persistent connection to the RESTCONF client. If the connection goes down, immediately start trying to reconnect to it, using the reconnection strategy. This connection type minimizes any RESTCONF client to RESTCONF server data-transfer delay, albeit at the expense of holding resources longer."; - uses keep-alives-container { - refine keep-alives/interval-secs { - default 15; // 15 seconds for call-home sessions + + container keep-alives { + description + "Configures the keep-alive policy, to proactively + test the aliveness of the TLS client. An + unresponsive TLS client will be dropped after + approximately (max-attempts * max-wait) seconds."; + reference + "RFC YYYY: NETCONF Call Home and RESTCONF Call Home, + Section 3.1, item S6"; + leaf max-wait { + type uint16 { + range "1..max"; + } + units seconds; + default 30; + description + "Sets the amount of time in seconds after which + if no data has been received from the TLS + client, a TLS-level message will be sent to + test the aliveness of the TLS client."; + } + leaf max-attempts { + type uint8; + default 3; + description + "Sets the number of sequential keep-alive messages + that can fail to obtain a response from the TLS + client before assuming the TLS client is no + longer alive."; } } } } case periodic-connection { container periodic { + presence true; description - "Periodically connect to RESTCONF client, using the - reconnection strategy, so the RESTCONF client can - deliver pending messages to the RESTCONF server. - - For messages the RESTCONF server wants to send to - to the RESTCONF client, the RESTCONF server should - proactively connect to the RESTCONF client, if - not already, to send the messages immediately."; - leaf timeout-mins { - type uint8; + "Periodically connect to the RESTCONF client, so that + the RESTCONF client may deliver messages pending for + the RESTCONF server. The RESTCONF client is expected + to close the connection when it is ready to release + it, thus starting the RESTCONF server's timer until + next connection."; + leaf reconnect-timeout { + type uint16 { + range "1..max"; + } units minutes; - default 5; + default 60; description "The maximum amount of unconnected time the RESTCONF - server will wait until establishing a connection to - the RESTCONF client again. The RESTCONF server MAY - establish a connection before this time if it has - data it needs to send to the RESTCONF 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 RESTCONF server should wait - after last receiving data from or sending data to - the RESTCONF client's endpoint before closing its - connection to it. This is an optimization to - prevent unnecessary connections."; + server will wait before re-establishing a connection + to the RESTCONF client. The RESTCONF server may + initiate a connection before this time if desired + (e.g., to deliver a notification)."; } - } } } } container reconnect-strategy { description "The reconnection strategy guides how a RESTCONF server reconnects to an RESTCONF client, after losing a connection to it, even if due to a reboot. The RESTCONF server starts with the specified endpoint and tries to connect to it @@ -1508,136 +1582,117 @@ } } } } container reconnect-strategy { description "The reconnection strategy guides how a RESTCONF server reconnects to an RESTCONF client, after losing a connection to it, even if due to a reboot. The RESTCONF server starts with the specified endpoint and 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)."; + 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. RESTCONF servers - SHOULD support this flag across reboots."; + the endpoint last connected to. If no previous + connection has ever been established, then the + first endpoint configured is used. RESTCONF + servers SHOULD be able to remember the last + endpoint connected to across reboots."; } } default first-listed; description "Specifies which of the RESTCONF client's endpoints the RESTCONF server should start with when trying to connect - to the RESTCONF client. If no previous connection has - ever been established, last-connected defaults to - the first endpoint listed."; + to the RESTCONF client."; } - 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 max-attempts { + type uint8 { + range "1..max"; } - leaf count-max { - type uint8; default 3; description "Specifies the number times the RESTCONF server tries to connect to a specific endpoint before moving on to the next endpoint in the list (round robin)."; } } } } - } - grouping client-cert-auth-container { - description - "This grouping is used only to help improve readability - of the YANG module."; container client-cert-auth { if-feature client-cert-auth; description "Container for TLS client certificate 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. 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."; + a RESTCONF server can use to authenticate RESTCONF client + certificates."; + reference + "RFC XXXX: RESTCONF Protocol, Sections 2.3 and 2.5."; leaf-list trusted-ca-cert { type binary; - ordered-by system; nacm:default-deny-write; 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"; } } container trusted-client-certs { description - "A list of client certificates that a NETCONF server can - use to authenticate a NETCONF client's certificate. A + "A list of client certificates that a RESTCONF server can + use to authenticate a RESTCONF client's certificate. A client's certificate is authenticated if it is an exact - match to a configured trusted client certificates."; + match to a configured trusted client certificate."; leaf-list trusted-client-cert { type binary; - ordered-by system; nacm:default-deny-write; description - "The binary certificate structure, as - specified by RFC 5246, Section 7.4.6, i.e.,: - - opaque ASN.1Cert<1..2^24>; - + "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"; } } container cert-maps { 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 + "The cert-maps container is used by a RESTCONF server to + map the RESTCONF client's presented X.509 certificate to a + RESTCONF username. If no matching and valid cert-to-name + list entry can be found, then the RESTCONF server MUST + close the connection, and MUST NOT accept RESTCONF messages over it."; + reference + "RFC XXXX: RESTCONF Protocol, Section 2.5"; } } } - grouping certificates-container { + grouping certificates-grouping { description "This grouping is used by both the listen and call-home containers"; container certificates { description "Parent container for the list of certificates."; leaf-list certificate { type string; min-elements 1; description @@ -1647,172 +1702,25 @@ configured on the system. How valid values are discovered is outside the scope of this module, but they are envisioned to be the keys for a list of certificates provided by another YANG module"; reference "RFC 5246: The TLS Protocol, Section 7.4.2"; } } } - grouping address-and-port-grouping { - description - "This grouping is usd by both the ssh and tls containers - for listen configuration."; - 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 RESTCONF server - listens on."; - } - } - - grouping endpoints-container { - description - "This grouping is used by both the ssh and tls containers - for call-home configurations."; - 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 RESTCONF client. - 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 a hostname is provided and DNS resolves to more than - one IP address, the RESTCONF server 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 RESTCONF server will - use the IANA-assigned well-known port if not specified."; - } - } - } - } - - grouping keep-alives-container { - description - "This grouping is use by both listen and call-home configurations."; - container keep-alives { - description - "Configures the keep-alive policy, to proactively test the - aliveness of the RESTCONF client."; - reference - "RFC VVVV: NETCONF Server and RESTCONF Server Configuration - Models, Section 4"; - leaf interval-secs { - type uint8; - units seconds; - description - "Sets a timeout interval in seconds after which if no data - has been received from the RESTCONF client, a message will - be sent to request a response from the RESTCONF client. 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 RESTCONF client before - assuming the RESTCONF client is no longer alive. If this - threshold is reached, the transport-level connection will - be disconnected, which will trigger the reconnection - strategy). The interval timer is reset after each - transmission, thus an unresponsive RESTCONF client will - be dropped after approximately (count-max * interval-secs) - seconds."; - } - } - } } -5. Implementation strategy for keep-alives - - One of the objectives listed above, Keep-alives for persistent - connections Section 2.6.6, indicates a need for a "keep-alive" - mechanism. This section specifies how the keep-alive mechanism is to - be implemented for both the SSH and TLS transports. - - Both SSH and TLS have the ability to support keep-alives securely. - Using the strategies listed below, the keep-alive messages are sent - inside the encrypted tunnel and thus immune to attack. - -5.1. Keep-alives for SSH - - The SSH keep-alive solution that is expected to be used is 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 be used, implementations are free to - pick values of their choosing. - -5.2. 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 TLS - connections, devices SHOULD advertise "peer_allowed_to_send", as per - [RFC6520]. This advertisement is not a "MUST" in order to - grandfather existing NETCONF/RESTCONF over TLS implementations. For - NETCONF Call Home or RESTCONF Call Home, the network management - system MUST advertise "peer_allowed_to_send" per [RFC6520]. This is - a "MUST" so as to ensure devices can depend on it always being there - for call home connections, which is when keep-alives are needed the - most. - -6. 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]. +5. Security Considerations There are a number of data nodes defined in the "ietf-netconf-server" YANG module which are readable 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 their sensitivity/ vulnerability. netconf-server/tls/client-auth/trusted-ca-certs: @@ -1836,21 +1744,21 @@ certificates. Write access to this node is protected using an nacm:default-deny-write statement. restconf-server/tls/client-auth/trusted-client-certs: o This container contains certificates that a RESTCONF server is to trust directly when authenticating X.509-based client certificates. Write access to this node is protected using an nacm:default-deny-write statement. -7. IANA Considerations +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-restconf-server @@ -1864,285 +1772,2124 @@ name: ietf-netconf-server namespace: urn:ietf:params:xml:ns:yang:ietf-netconf-server prefix: ncserver reference: RFC VVVV name: ietf-restconf-server namespace: urn:ietf:params:xml:ns:yang:ietf-restconf-server prefix: rcserver reference: RFC VVVV -8. Other Considerations +7. Other Considerations The YANG modules define herein do not themselves support virtual routing and forwarding (VRF). It is expected that external modules will augment in VRF designations when needed. -9. Acknowledgements +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, Mehmet Ersue, David Lamparter, Alan Luchuk, Ladislav Lhotka, Radek Krejci, Tom Petch, Phil Shafer, and Bert Wijnen. 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. -10. References +9. References -10.1. Normative 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. [RFC6187] Igoe, K. and D. Stebila, "X.509v3 Certificates for Secure Shell Authentication", RFC 6187, March 2011. [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. [RFC7407] Bjorklund, M. and J. Schoenwaelder, "A YANG Data Model for SNMP Configuration", RFC 7407, 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, June 2015. + [draft-ietf-netconf-call-home] Watsen, K., "NETCONF Call Home and RESTCONF Call Home", draft-ieft-netconf-call-home-02 (work in progress), 2014. [draft-ietf-netconf-restconf] Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF Protocol", draft-ieft-netconf-restconf-04 (work in progress), 2014. - [draft-ietf-netconf-rfc5539bis] - Badra, M., Luchuk, A., and J. Schoenwaelder, "Using the - NETCONF Protocol over Transport Layer Security (TLS)", - draft-ietf-netconf-rfc5539bis-06 (work in progress), 2014. - -10.2. Informative References +9.2. Informative References [RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688, January 2004. -Appendix A. Examples +Appendix A. Alternative solution addressing Issue #49 -A.1. NETCONF Configuration using SSH Transport + Option #4 for Issue #49 proposed to define configuration for a + keychain and on-going discussion proposed to create reusable + groupings for SSH/TLS servers (referencing keys and certificates held + in the keychain) that the NETCONF/RESTCONF servers would uses. This + relationship is illustrated by the diagram below. - The following example illustrates the 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. + +-------------+ + |ietf-keychain| + +-------------+ + ^ ^ + | | + | | + +------------+ +------------+ + | | + +---------------+ +------------------+ + |ietf-ssh-server| | ietf-tls-server | + +---------------+ +------------------+ + ^ ^ ^ + | | | + | | | + | +--------------------+ | + | | | + +-------------------+ +--------------------+ + |ietf-netconf-server| |ietf-restconf-server| + +-------------------+ +--------------------+ + + The following sections each of the five YANG modules above. + +A.1. The Keychain Model + +A.1.1. Tree Diagram +module: ietf-keychain + +--rw keychain + +--rw private-keys + | +--rw private-key* [name] + | +--rw name string + | +--ro algorithm? enumeration + | +--ro key-length? uint32 + | +--ro public-key? string + | +--rw certificates + | +--rw certificate* [name] + | +--rw name string + | +--rw chain? binary + +--rw trusted-certificates* [name] + +--rw name string + +--rw trusted-certificate* [name] + +--rw name string + +--rw certificate? binary +rpcs: + +---x generate-certificate-signing-request + | +---w input + | | +---w private-key? -> /keychain/private-keys/private-key/name + | | +---w subject binary + | | +---w attributes? binary + | +--ro output + | +--ro certificate-signing-request binary + +---x generate-private-key + +---w input + +---w name string + +---w algorithm enumeration + +---w key-length uint32 + +A.1.2. Example Usage + + + + + + + TPM key + rsa + 2048 + + cztvaWRoc2RmZ2tqaHNkZmdramRzZnZzZGtmam5idnNvO2RmanZvO3NkZ + mJpdmhzZGZpbHVidjtvc2lkZmhidml1bHNkYmZ2aXNiZGZpYmhzZG87Zm + JvO3NkZ25iO29pLmR6Zgo= + + + + IDevID Certificate + + LS0tLS1CRUdJTiBDRVJUSUZJQ0FURS0tLS0tCk1JSUNrekNDQWZ5Z + 0F3SUJBZ0lKQUpRT2t3bGpNK2pjTUEwR0NTcUdTSWIzRFFFQkJRVU + FNRFF4Q3pBSkJnTlYKQkFZVEFsVlRNUkF3RGdZRFZRUUtFd2RsZUd + GdGNHeGxNUk13RVFZRFZRUURFd3BEVWt3Z1NYTnpkV1Z5TUI0WApE + diR1V4RXpBUkJnTlZCQU1UQ2tOU1RDQkpjM04xWlhJd2daOHdEUVl + KS29aSWh2Y04KQVFFQkJRQURnWTBBTUlHSkFvR0JBTXVvZmFPNEV3 + El1QWMrQ1RsTkNmc0d6cEw1Um5ydXZsOFRIcUJTdGZQY3N0Zk1KT1 + FaNzlnNlNWVldsMldzaHE1bUViCkJNNitGNzdjbTAvU25FcFE0TnV + bXBDT2YKQWdNQkFBR2pnYXd3Z2Frd0hRWURWUjBPQkJZRUZKY1o2W + URiR0lPNDB4ajlPb3JtREdsRUNCVTFNR1FHQTFVZApJd1JkTUZ1QU + ZKY1o2WURiR0lPNDB4ajlPb3JtREdsRUNCVTFvVGlrTmpBME1Rc3d + mMKTUE0R0ExVWREd0VCL3dRRUF3SUNCREFTQmdOVkhSTUJBZjhFQ0 + RBR0FRSC9BZ0VBTUEwR0NTcUdTSWIzRFFFQgpCUVVBQTRHQkFMMmx + rWmFGNWcyaGR6MVNhZnZPbnBneHA4eG00SHRhbStadHpLazFlS3Bx + TXp4YXJCbFpDSHlLCklVbC9GVzRtV1RQS1VDeEtFTE40NEY2Zmk2d + c4d0tSSElkYW1WL0pGTmlQS0VXSTF4K1I1aDZmazcrQzQ1QXg1RWV + SWHgzZjdVM2xZTgotLS0tLUVORCBDRVJUSUZJQ0FURS0tLS0tCg== + + + + + + + + + Trusted certificates for netconf/restconf client + + George Jetson + + QmdOVkJBWVRBbFZUTVJBd0RnWURWUVFLRXdkbAplR0Z0Y0d4bE1RNHdEQ + MkF6a3hqUDlVQWtHR0dvS1U1eUc1SVR0Wm0vK3B0R2FieXVDMjBRd2kvZ + 25PZnpZNEhONApXY0pTaUpZK2xtYWs3RTRORUZXZS9RdGp4NUlXZmdvN2 + RV0JCU2t2MXI2SFNHeUFUVkpwSmYyOWtXbUU0NEo5akJrQmdOVkhTTUVY + VEJiZ0JTWEdlbUEKMnhpRHVOTVkvVHFLNWd4cFJBZ1ZOYUU0cERZd05ER + UxNQWtHQTFVRUJoTUNWVk14RURBT0JnTlZCQW9UQjJWNApZVzF3YkdVeE + V6QVJCZ05WQkFNVENrTlNUQ0JKYzNOMVpYS0NDUUNVRHBNSll6UG8zREF + NQmdOVkhSTUJBZjhFCkFqQUFNQTRHQTFVZER3RUIvd1FFQXdJSGdEQnBC + Z05WSFI4RVlqQmdNRjZnSXFBZ2hoNW9kSFJ3T2k4dlpYaGgKYlhCc1pTN + WpiMjB2WlhoaGJYQnNaUzVqY215aU9LUTJNRFF4Q3pBSkJnTlZCQVlUQW + xWVE1SQXdEZ1lEVlFRSwpFd2RsZUdGdGNHeGxNUk13RVFZRFZRUURFd3B + EVWt3Z1NYTnpkV1Z5TUEwR0NTcUdTSWIzRFFFQkJRVUFBNEdCCkFFc3BK + WmdsK2gyTTg3QmtGMjhWbW1CdFFVaWc3OEgrRkYyRTFwdSt4ZVRJbVFFM + TQzcjFZSjk0M1FQLzV5eGUKN2QxMkxCV0dxUjUrbEl5N01YL21ka2M4al + zSFNwSDdwVXBCYnA4dmtNanFtZjJma3RqZHBxeFppUUtTbndWZTF2Zwot + LS0tLUVORCBDRVJUSUZJQ0FURS0tLS0tCg== + + + + + Fred Flinstone + + VlEVlFRREV3Vm9ZWEJ3ZVRDQm56QU5CZ2txaGtpRzl3MEJBUUVGQUFPQm + pRQXdnWWtDCmdZRUE1RzRFSWZsS1p2bDlXTW44eUhyM2hObUFRaUhVUzV + rRUpPQy9hSFA3eGJXQW1ra054ZStUa2hrZnBsL3UKbVhsTjhSZUd1ODhG + NGcEk3UE90cnNFVjRwTUNBd0VBQWFPQ0FSSXdnZ0VPCk1CMEdBMVVkRGd + VEJiZ0JTWEdlbUEKMnhpRHVOTVkvVHFLNWd4cFJBZ1ZOYUU0cERZd05ER + V6QVJCZ05WQkFNVENrTlNUQ0JKYzNOMVpYS0NDUUNVRHBNSll6UG8zREF + NQmdOVkhSTUJBZjhFCkFqQUFNQTRHQTFVZER3RUIvd1FFQXdJSGdEQnBC + Z05WSFI4RVlqQmdNRjZnSXFBZ2hoNW9kSFJ3T2k4dlpYaGgKYlhCc1pTN + WpiMjB2WlhoaGJYQnNaUzVqY215aU9LUTJNRFF4Q3pBSkJnTlZCQVlUQW + xWVE1SQXdEZ1lEVlFRSwpFd2RsZUdGdGNHeGxNUk13RVFZRFZRUURFd3B + EVWt3Z1NYTnpkV1Z5TUEwR0NTcUdTSWIzRFFFQkJRVUFBNEdCCkFFc3BK + WmdsK2gyTTg3QmtGMjhWbW1CdFFVaWc3OEgrRkYyRTFwdSt4ZVRJbVFFM + lLQllsdWpOcjFTMnRLR05EMUc2OVJpK2FWNGw2NTdZNCtadVJMZgpRYjk + zSFNwSDdwVXBCYnA4dmtNanFtZjJma3RqZHBxeFppUUtTbndWZTF2Zwot + QWtUOCBDRVUUZJ0RUF== + + + + + + + Trust anchors for netconf/restconf clients + + Example.com + + WmdsK2gyTTg3QmtGMjhWbW1CdFFVaWc3OEgrRkYyRTFwdSt4ZVRJbVFFM + lLQllsdWpOcjFTMnRLR05EMUc2OVJpK2FWNGw2NTdZNCtadVJMZgpRYjk + zSFNwSDdwVXBCYnA4dmtNanFtZjJma3RqZHBxeFppUUtTbndWZTF2Zwot + NGcEk3UE90cnNFVjRwTUNBd0VBQWFPQ0FSSXdnZ0VPCk1CMEdBMVVkRGd + VEJiZ0JTWEdlbUEKMnhpRHVOTVkvVHFLNWd4cFJBZ1ZOYUU0cERZd05ER + V6QVJCZ05WQkFNVENrTlNUQ0JKYzNOMVpYS0NDUUNVRHBNSll6UG8zREF + NQmdOVkhSTUJBZjhFCkFqQUFNQTRHQTFVZER3RUIvd1FFQXdJSGdEQnBC + Z05WSFI4RVlqQmdNRjZnSXFBZ2hoNW9kSFJ3T2k4dlpYaGgKYlhCc1pTN + WpiMjB2WlhoaGJYQnNaUzVqY215aU9LUTJNRFF4Q3pBSkJnTlZCQVlUQW + QmdOVkJBWVRBbFZUTVJBd0RnWURWUVFLRXdkbAplR0Z0Y0d4bE1RNHdEQ + MkF6a3hqUDlVQWtHR0dvS1U1eUc1SVR0Wm0vK3B0R2FieXVDMjBRd2kvZ + 25PZnpZNEhONApXY0pTaUpZK2xtYWs3RTRORUZXZS9RdGp4NUlXZmdvN2 + RJSUJQFRStS0Cg== + + + + + + + Trust anchors for random HTTPS servers + + Example.com + + NGcEk3UE90cnNFVjRwTUNBd0VBQWFPQ0FSSXdnZ0VPCk1CMEdBMVVkRGd + VEJiZ0JTWEdlbUEKMnhpRHVOTVkvVHFLNWd4cFJBZ1ZOYUU0cERZd05ER + V6QVJCZ05WQkFNVENrTlNUQ0JKYzNOMVpYS0NDUUNVRHBNSll6UG8zREF + Z05WSFI4RVlqQmdNRjZnSXFBZ2hoNW9kSFJ3T2k4dlpYaGgKYlhCc1pTN + QmdOVkJBWVRBbFZUTVJBd0RnWURWUVFLRXdkbAplR0Z0Y0d4bE1RNHdEQ + MkF6a3hqUDlVQWtHR0dvS1U1eUc1SVR0Wm0vK3B0R2FieXVDMjBRd2kvZ + NQmdOVkhSTUJBZjhFCkFqQUFNQTRHQTFVZER3RUIvd1FFQXdJSGdEQnBC + WmdsK2gyTTg3QmtGMjhWbW1CdFFVaWc3OEgrRkYyRTFwdSt4ZVRJbVFFM + lLQllsdWpOcjFTMnRLR05EMUc2OVJpK2FWNGw2NTdZNCtadVJMZgpRYjk + zSFNwSDdwVXBCYnA4dmtNanFtZjJma3RqZHBxeFppUUtTbndWZTF2Zwot + 25PZnpZNEhONApXY0pTaUpZK2xtYWs3RTRORUZXZS9RdGp4NUlXZmdvN2 + WpiMjB2WlhoaGJYQnNaUzVqY215aU9L= + + + + + + +A.1.3. YANG Model + + file "ietf-keychain@2015-07-06.yang" + + module ietf-keychain { + yang-version 1.1; + + namespace "urn:ietf:params:xml:ns:yang:ietf-keychain"; + prefix "kc"; + + organization + "IETF NETCONF (Network Configuration) Working Group"; + + contact + "WG Web: + WG List: + + WG Chair: Mehmet Ersue + + + WG Chair: Mahesh Jethanandani + + + Editor: Kent Watsen + "; + + description + "This module defines a keychain to centralize management of + security credentials. + + 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 VVVV; see + the RFC itself for full legal notices."; + + revision "2015-07-06" { + description + "Initial version"; + reference + "RFC VVVV: NETCONF Server and RESTCONF Server Configuration + Models"; + } + + container keychain { + description + "A list of private-keys and their associated certificates, as + well as lists of trusted certificates for client certificate + authentication. RPCs are provided to generate a new private + key and to generate a certificate signing requests."; + + container private-keys { + description + "A list of private key maintained by the keychain."; + list private-key { + key name; + description + "A private key."; + leaf name { + type string; + description + "An arbitrary name for the private key."; + } + leaf algorithm { + type enumeration { + enum rsa { description "TBD"; } + enum dsa { description "TBD"; } + enum secp192r1 { description "TBD"; } + enum sect163k1 { description "TBD"; } + enum sect163r2 { description "TBD"; } + enum secp224r1 { description "TBD"; } + enum sect233k1 { description "TBD"; } + enum sect233r1 { description "TBD"; } + enum secp256r1 { description "TBD"; } + enum sect283k1 { description "TBD"; } + enum sect283r1 { description "TBD"; } + enum secp384r1 { description "TBD"; } + enum sect409k1 { description "TBD"; } + enum sect409r1 { description "TBD"; } + enum secp521r1 { description "TBD"; } + enum sect571k1 { description "TBD"; } + enum sect571r1 { description "TBD"; } + } + config false; + description + "The algorithm used by the private key."; + } + leaf key-length { + type uint32; + config false; + description + "The key-length used by the private key."; + } + leaf public-key { + type string; + config false; + description + "The public-key matching the private key."; + } + container certificates { + list certificate { + key name; + description + "A certificate for this public key."; + leaf name { + type string; + description + "An arbitrary name for the certificate."; + } + leaf chain { + type binary; + description + "The certificate itself, as well as an ordered + sequence of intermediate certificates leading + to a trust anchor, as specified by RFC 5246, + Section 7.4.2."; + reference + "RFC 5246: The Transport Layer Security (TLS) + Protocol Version 1.2"; + } + } + description + "A list of certificates for this public key."; + } + action generate-certificate-signing-request { + description + "Generates a certificate signing request structure for + the associated private key using the passed subject + and attribute values."; + input { + leaf subject { + type binary; + mandatory true; + description + "The 'subject' field in the CertificationRequestInfo + defined in RFC 2986, Section 4.1."; + reference + "RFC 2986: PKCS #10: Certification Request Syntax + Specification Version 1.7"; + } + leaf attributes { + type binary; + description + "The 'attributes' field in the CertificationRequestInfo + defined in RFC 2986, Section 4.1."; + reference + "RFC 2986: PKCS #10: Certification Request Syntax + Specification Version 1.7"; + } + } + output { + leaf certificate-signing-request { + type binary; + mandatory true; + description + "The CertificationRequestInfo structure as specified + by RFC 2986, Section 4.1."; + reference + "RFC 2986: PKCS #10: Certification Request Syntax + Specification Version 1.7"; + } + } + } + + } + action generate-private-key { + description + "Generates a private key using the specified algorithm and + key length."; + input { + leaf name { + type string; + mandatory true; + description + "The name this private-key should have when listed in + /keychain/private-keys/private-key. As such, the + passed value must not match any existing 'name' value."; + } + leaf algorithm { + type enumeration { + enum rsa { description "TBD"; } + enum dsa { description "TBD"; } + enum secp192r1 { description "TBD"; } + enum sect163k1 { description "TBD"; } + enum sect163r2 { description "TBD"; } + enum secp224r1 { description "TBD"; } + enum sect233k1 { description "TBD"; } + enum sect233r1 { description "TBD"; } + enum secp256r1 { description "TBD"; } + enum sect283k1 { description "TBD"; } + enum sect283r1 { description "TBD"; } + enum secp384r1 { description "TBD"; } + enum sect409k1 { description "TBD"; } + enum sect409r1 { description "TBD"; } + enum secp521r1 { description "TBD"; } + enum sect571k1 { description "TBD"; } + enum sect571r1 { description "TBD"; } + } + mandatory true; + description + "The algorithm to be used."; + } + leaf key-length { + type uint32; + mandatory true; + description + "The key length to be used."; + } + } + } + } + list trusted-certificates { + key name; + description + "A list of lists of trusted certificates."; + leaf name { + type string; + description + "An arbitrary name for this list of trusted certificates."; + } + list trusted-certificate { + key name; + description + "A list of trusted certificates for a specific use."; + leaf name { + type string; + description + "An arbitrary name for this trusted certificate."; + } + leaf certificate { + type binary; + 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"; + } + } + } + } + + rpc generate-certificate-signing-request { + description + "Generates a certificate signing request structure for + the specified private key using the passed subject + and attribute values."; + input { + leaf private-key { + type leafref { + path "/keychain/private-keys/private-key/name"; + } + description + "The private key to generate the certificate signing + request for."; + } + leaf subject { + type binary; + mandatory true; + description + "The 'subject' field in the CertificationRequestInfo + defined in RFC 2986, Section 4.1."; + reference + "RFC 2986: PKCS #10: Certification Request Syntax + Specification Version 1.7"; + } + leaf attributes { + type binary; + description + "The 'attributes' field in the CertificationRequestInfo + defined in RFC 2986, Section 4.1."; + reference + "RFC 2986: PKCS #10: Certification Request Syntax + Specification Version 1.7"; + } + } + output { + leaf certificate-signing-request { + type binary; + mandatory true; + description + "The CertificationRequestInfo structure as specified + by RFC 2986, Section 4.1."; + reference + "RFC 2986: PKCS #10: Certification Request Syntax + Specification Version 1.7"; + } + } + } + + rpc generate-private-key { + description + "Generates a private key using the specified algorithm and + key length."; + input { + leaf name { + type string; + mandatory true; + description + "The name this private-key should have when listed in + /keychain/private-keys/private-key. As such, the + passed value must not match any existing 'name' value."; + } + leaf algorithm { + type enumeration { + enum rsa { description "TBD"; } + enum dsa { description "TBD"; } + enum secp192r1 { description "TBD"; } + enum sect163k1 { description "TBD"; } + enum sect163r2 { description "TBD"; } + enum secp224r1 { description "TBD"; } + enum sect233k1 { description "TBD"; } + enum sect233r1 { description "TBD"; } + enum secp256r1 { description "TBD"; } + enum sect283k1 { description "TBD"; } + enum sect283r1 { description "TBD"; } + enum secp384r1 { description "TBD"; } + enum sect409k1 { description "TBD"; } + enum sect409r1 { description "TBD"; } + enum secp521r1 { description "TBD"; } + enum sect571k1 { description "TBD"; } + enum sect571r1 { description "TBD"; } + } + mandatory true; + description + "The algorithm to be used."; + } + leaf key-length { + type uint32; + mandatory true; + description + "The key length to be used."; + } + } + } + } + + + +A.2. The SSH Server Model + +A.2.1. Tree Diagram + + The following tree diagram is faked, as a module having only a + grouping in it has no tree diagram. However, for illustrative + purposes, a container has been added as nothing more than a "uses" + statement of the grouping. + +module: ietf-ssh-server + +--rw fake-ssh-server + +--rw host-keys + | +--rw host-key* [name] + | +--rw name string + | +--rw (type)? + | +--:(public-key) + | | +--rw public-key? -> /kc:keychain/private-keys/private-key/name + | +--:(certificate) + | +--rw certificate? -> /kc:keychain/private-keys/private-key/certificates/certificate/name {ssh-x509-certs}? + +--rw client-cert-auth {ssh-x509-certs}? + +--rw trusted-ca-certs? -> /kc:keychain/trusted-certificates/name + +--rw trusted-client-certs? -> /kc:keychain/trusted-certificates/name + +A.2.2. Example Usage + + + + + IDevID + + IDevID Certificate + + + + + + + Trusted certificates for netconf/restconf clients + + + Trust anchors for netconf/restconf clients + + + + +A.2.3. YANG Model + + file "ietf-ssh-server@2015-07-06.yang" + +module ietf-ssh-server { + yang-version 1.1; + + namespace "urn:ietf:params:xml:ns:yang:ietf-ssh-server"; + prefix "ts"; + import ietf-keychain { + prefix kc; // RFC VVVV + } + + organization + "IETF NETCONF (Network Configuration) Working Group"; + + contact + "WG Web: + WG List: + + WG Chair: Mehmet Ersue + + + WG Chair: Mahesh Jethanandani + + + Editor: Kent Watsen + "; + + description + "This module defines a reusable grouping for a SSH server that + can be used as a basis for specific SSH server instances. + + 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 VVVV; see + the RFC itself for full legal notices."; + + revision "2015-07-06" { + description + "Initial version"; + reference + "RFC VVVV: NETCONF Server and RESTCONF Server Configuration + Models"; + } + + // features + feature ssh-x509-certs { + description + "The ssh-x509-certs feature indicates that the NETCONF server + supports RFC 6187"; + reference + "RFC 6187: X.509v3 Certificates for Secure Shell Authentication"; + } + + // grouping + grouping ssh-server-grouping { + description + "A reusable grouping for a SSH server that can be used as a + basis for specific SSH server instances."; + + container host-keys { + description + "The list of host-keys the SSH server will present when + establishing a SSH connection."; + list host-key { + key name; + min-elements 1; + ordered-by user; + description + "An ordered list of hostkeys the SSH server advertises + when sending its ??? message."; + reference + "RFC ????: ..."; + leaf name { + type string; + mandatory true; + description + "An arbitrary name for this host-key"; + } + choice type { + leaf public-key { + type leafref { + path "/kc:keychain/kc:private-keys/kc:private-key/kc:name"; + } + description + "The name of a private-key in the keychain."; + } + leaf certificate { + if-feature ssh-x509-certs; + type leafref { + path "/kc:keychain/kc:private-keys/kc:private-key/kc:certificates/kc:certificate/kc:name"; + } + description + "The name of a certificate in the keychain."; + } + + } + } + } + + container client-cert-auth { + if-feature ssh-x509-certs; + description + "A reference to a list of trusted certificate authority (CA) + certificates and a reference to a list of trusted client + certificates."; + leaf trusted-ca-certs { + type leafref { + path "/kc:keychain/kc:trusted-certificates/kc:name"; + } + description + "A reference to a list of certificate authority (CA) + certificates used by the SSH server to authenticate + SSH client certificates."; + } + + leaf trusted-client-certs { + type leafref { + path "/kc:keychain/kc:trusted-certificates/kc:name"; + } + description + "A reference to a list of client certificates used by + the SSH server to authenticate SSH client certificates. + A clients certificate is authenticated if it is an + exact match to a configured trusted client certificate."; + } + } + } +} + + + +A.3. The TLS Server Model + +A.3.1. Tree Diagram + + The following tree diagram is faked, as a module having only a + grouping in it has no tree diagram. However, for illustrative + purposes, a container has been added as nothing more than a "uses" + statement of the grouping. + +module: ietf-tls-server + +--rw fake-tls-server + +--rw certificates + | +--rw certificate* [name] + | +--rw name -> /kc:keychain/private-keys/private-key/certificates/certificate/name + +--rw client-auth + +--rw trusted-ca-certs? -> /kc:keychain/trusted-certificates/name + +--rw trusted-client-certs? -> /kc:keychain/trusted-certificates/name + +A.3.2. Example Usage + + + + + IDevID Certificate + + + + + Trusted certificates for netconf/restconf clients + + + Trust anchors for netconf/restconf clients + + + + +A.3.3. YANG Model + + file "ietf-tls-server@2015-07-06.yang" + +module ietf-tls-server { + yang-version 1.1; + + namespace "urn:ietf:params:xml:ns:yang:ietf-tls-server"; + prefix "ts"; + + import ietf-keychain { + prefix kc; // RFC VVVV + } + + organization + "IETF NETCONF (Network Configuration) Working Group"; + + contact + "WG Web: + WG List: + + WG Chair: Mehmet Ersue + + + WG Chair: Mahesh Jethanandani + + + Editor: Kent Watsen + "; + + description + "This module defines a reusable grouping for a TLS server that + can be used as a basis for specific TLS server instances. + + 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 VVVV; see + the RFC itself for full legal notices."; + + revision "2015-07-06" { + description + "Initial version"; + reference + "RFC VVVV: NETCONF Server and RESTCONF Server Configuration + Models"; + } + + grouping tls-server-grouping { + description + "A reusable grouping for a TLS server that can be used as a + basis for specific TLS server instances."; + + container certificates { + description + "The list of certificates the TLS server will present when + establishing a TLS connection."; + list certificate { + key name; + min-elements 1; + description + "An unordered list of certificates the TLS server can pick + from when sending its Server Certificate message."; + reference + "RFC 5246: The TLS Protocol, Section 7.4.2"; + leaf name { + type leafref { + path "/kc:keychain/kc:private-keys/kc:private-key/kc:certificates/kc:certificate/kc:name"; + } + description + "The name of the certificate in the keychain."; + } + } + } + + container client-auth { + description + "A reference to a list of trusted certificate authority (CA) + certificates and a reference to a list of trusted client + certificates."; + leaf trusted-ca-certs { + type leafref { + path "/kc:keychain/kc:trusted-certificates/kc:name"; + } + description + "A reference to a list of certificate authority (CA) + certificates used by the TLS server to authenticate + TLS client certificates."; + } + + leaf trusted-client-certs { + type leafref { + path "/kc:keychain/kc:trusted-certificates/kc:name"; + } + description + "A reference to a list of client certificates used by + the TLS server to authenticate TLS client certificates. + A clients certificate is authenticated if it is an + exact match to a configured trusted client certificate."; + } + } + } +} + + +A.4. The NETCONF Server Model + +A.4.1. Tree Diagram + +module: ietf-netconf-server-new + +--rw netconf-server + +--rw session-options + | +--rw hello-timeout? uint16 + +--rw listen {(ssh-listen or tls-listen)}? + | +--rw max-sessions? uint16 + | +--rw idle-timeout? uint16 + | +--rw endpoint* [name] + | +--rw name string + | +--rw (transport) + | +--:(ssh) {ssh-listen}? + | | +--rw ssh + | | +--rw address? inet:ip-address + | | +--rw port? inet:port-number + | | +--rw host-keys + | | | +--rw host-key* [name] + | | | +--rw name string + | | | +--rw (type)? + | | | +--:(public-key) + | | | | +--rw public-key? -> /kc:keychain/private-keys/private-key/name + | | | +--:(certificate) + | | | +--rw certificate? -> /kc:keychain/private-keys/private-key/certificates/certificate/name {ssh-x509-certs}? + | | +--rw client-cert-auth {ssh-x509-certs}? + | | +--rw trusted-ca-certs? -> /kc:keychain/trusted-certificates/name + | | +--rw trusted-client-certs? -> /kc:keychain/trusted-certificates/name + | +--:(tls) {tls-listen}? + | +--rw tls + | +--rw address? inet:ip-address + | +--rw port? inet:port-number + | +--rw certificates + | | +--rw certificate* [name] + | | +--rw name -> /kc:keychain/private-keys/private-key/certificates/certificate/name + | +--rw client-auth + | +--rw trusted-ca-certs? -> /kc:keychain/trusted-certificates/name + | +--rw trusted-client-certs? -> /kc:keychain/trusted-certificates/name + | +--rw cert-maps + | +--rw cert-to-name* [id] + | +--rw id uint32 + | +--rw fingerprint x509c2n:tls-fingerprint + | +--rw map-type identityref + | +--rw name string + +--rw call-home {(ssh-call-home or tls-call-home)}? + +--rw netconf-client* [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 + | | +--rw host-keys + | | | +--rw host-key* [name] + | | | +--rw name string + | | | +--rw (type)? + | | | +--:(public-key) + | | | | +--rw public-key? -> /kc:keychain/private-keys/private-key/name + | | | +--:(certificate) + | | | +--rw certificate? -> /kc:keychain/private-keys/private-key/certificates/certificate/name {ssh-x509-certs}? + | | +--rw client-cert-auth {ssh-x509-certs}? + | | +--rw trusted-ca-certs? -> /kc:keychain/trusted-certificates/name + | | +--rw trusted-client-certs? -> /kc:keychain/trusted-certificates/name + | +--:(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* [name] + | | +--rw name -> /kc:keychain/private-keys/private-key/certificates/certificate/name + | +--rw client-auth + | +--rw trusted-ca-certs? -> /kc:keychain/trusted-certificates/name + | +--rw trusted-client-certs? -> /kc:keychain/trusted-certificates/name + | +--rw cert-maps + | +--rw cert-to-name* [id] + | +--rw id uint32 + | +--rw fingerprint x509c2n:tls-fingerprint + | +--rw map-type identityref + | +--rw name string + +--rw connection-type + | +--rw (connection-type)? + | +--:(persistent-connection) + | | +--rw persistent! + | | +--rw idle-timeout? uint32 + | | +--rw keep-alives + | | +--rw max-wait? uint16 + | | +--rw max-attempts? uint8 + | +--:(periodic-connection) + | +--rw periodic! + | +--rw idle-timeout? uint16 + | +--rw reconnect_timeout? uint16 + +--rw reconnect-strategy + +--rw start-with? enumeration + +--rw max-attempts? uint8 + +A.4.2. Example Usage + + Configuring an SSH Server - - 600 - 3600 - - foo bar + netconf/ssh
11.22.33.44
- my-rsa-key - my-dss-key + + my-rsa-key + + + TPM key + + + + Trusted netconf/restconf client certificates + + + Trust anchors for netconf/restconf clients + + - + config-mgr east-data-center
11.22.33.44
 west-data-center
55.66.77.88
 - my-call-home-x509-key + + TPM key + - - - - - + - - QW4gRWFzdGVyIGVnZywgZm9yIHRob3NlIHdobyBtaWdodCBsb29rICA6KQo= - + Trusted netconf/restconf client certificates - - SSBhbSB0aGUgZWdnIG1hbiwgdGhleSBhcmUgdGhlIGVnZyBtZW4uCg== - - - SSBhbSB0aGUgd2FscnVzLCBnb28gZ29vIGcnam9vYi4K - + Trust anchors for netconf/restconf clients - + + + -A.2. NETCONF Configuration using TLS Transport - - The following example illustrates the 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. + Configuring a TLS Server - - - 600 - 3600 - + - primary-netconf-endpoint - -
11.22.33.44
- - fw1.east.example.com - - - - - - - config-mgr + netconf/tls - - - east-data-center
11.22.33.44
- - - west-data-center -
55.66.77.88
- - - fw1.east.example.com + IDevID Certificate - - - - - - QW4gRWFzdGVyIGVnZywgZm9yIHRob3NlIHdobyBtaWdodCBsb29rICA6KQo= - + Trusted netconf/restconf client certificates - - SSBhbSB0aGUgZWdnIG1hbiwgdGhleSBhcmUgdGhlIGVnZyBtZW4uCg== - - - SSBhbSB0aGUgd2FscnVzLCBnb28gZ29vIGcnam9vYi4K - + Trust anchors for netconf/restconf clients 1 11:0A:05:11:00 x509c2n:san-any 2 - 11:0A:05:11:00 + B3:4F:A1:8C:54 x509c2n:specified - Joe Cool + scooby-doo - -A.3. RESTCONF Configuration using TLS Transport - - The following example illustrates the response from a RESTCONF - server that only supports TLS, both listening for incoming - connections as well as calling home to a single application having - two endpoints. - - - - - primary-restconf-endpoint - -
11.22.33.44
- - fw1.east.example.com - - - + config-mgr east-data-center -
11.22.33.44
+
22.33.44.55
 west-data-center -
55.66.77.88
+
33.44.55.66
 - fw1.east.example.com + IDevID Certificate - + - + + +A.4.3. YANG Model + + This YANG module imports YANG types from [RFC6991] and [RFC7407]. + + file "ietf-netconf-server-new@2015-07-06.yang" + +module ietf-netconf-server-new { + yang-version 1.1; + + namespace "urn:ietf:params:xml:ns:yang:ietf-netconf-server-new"; + prefix "ncserver"; + + import ietf-inet-types { // RFC 6991 + prefix inet; + } + import ietf-x509-cert-to-name { // RFC 7407 + prefix x509c2n; + } + import ietf-ssh-server { // RFC VVVV + prefix ss; + } + import ietf-tls-server { // RFC VVVV + prefix ts; + } + + organization + "IETF NETCONF (Network Configuration) Working Group"; + + contact + "WG Web: + WG List: + + WG Chair: Mehmet Ersue + + + WG Chair: Mahesh Jethanandani + + + Editor: Kent Watsen + "; + + 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 VVVV; see + the RFC itself for full legal notices."; + + revision "2015-07-06" { + description + "Initial version"; + + reference + "RFC VVVV: NETCONF Server and RESTCONF Server Configuration + Models"; + } + + // Features + + 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 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 YYYY: NETCONF Call Home and RESTCONF Call Home"; + } + + 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 5539: Using the NETCONF Protocol over Transport + Layer Security (TLS) with Mutual X.509 + Authentication"; + } + + 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 YYYY: NETCONF Call Home and RESTCONF Call Home"; + } + + feature ssh-x509-certs { + description + "The ssh-x509-certs feature indicates that the NETCONF server + supports RFC 6187"; + reference + "RFC 6187: X.509v3 Certificates for Secure Shell Authentication"; + } + + // top-level container (groupings below) + container netconf-server { + description + "Top-level container for NETCONF server configuration."; + + container session-options { // SHOULD WE REMOVE THIS ALTOGETHER? + description + "NETCONF session options, independent of transport + or connection strategy."; + leaf hello-timeout { + type uint16; + units "seconds"; + default 600; + description + "Specifies the maximum number of seconds that a SSH/TLS + connection may wait for a hello message to be received. + A connection will be dropped if no hello message is + received before this number of seconds elapses. If set + to zero, then the server will wait forever for a hello + message."; + } + } + + container listen { + description + "Configures listen behavior"; + if-feature "(ssh-listen or tls-listen)"; + leaf max-sessions { + type uint16; + 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."; + } + 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; + description + "List of endpoints to listen for NETCONF connections on."; + 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 address-and-port-grouping { + refine port { + default 830; + } + } + uses ss:ssh-server-grouping; + } + } + case tls { + if-feature tls-listen; + container tls { + description + "TLS-specific listening configuration for inbound + connections."; + uses address-and-port-grouping { + refine port { + default 6513; + } + } + uses tls-server-grouping; + } + } + } + + } + } + + container call-home { + if-feature "(ssh-call-home or tls-call-home)"; + description + "Configures call-home behavior"; + list netconf-client { + key name; + description + "List of NETCONF clients the NETCONF server is to initiate + call-home connections to."; + leaf name { + type string; + description + "An arbitrary name for the remote NETCONF client."; + } + 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 endpoints-container { + refine endpoints/endpoint/port { + default 7777; + } + } + uses ss:ssh-server-grouping; + } + } + case tls { + if-feature tls-call-home; + container tls { + description + "Specifies TLS-specific call-home transport + configuration."; + uses endpoints-container { + refine endpoints/endpoint/port { + default 8888; + } + } + uses tls-server-grouping; + } + + } + } + container connection-type { + description + "Indicates the kind of connection to use."; + choice connection-type { + description + "Selects between available connection types."; + case persistent-connection { + container persistent { + presence true; + 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."; + leaf idle-timeout { + type uint32; + units "seconds"; + default 86400; // one day; + description + "Specifies the maximum number of seconds that a + 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."; + } + container keep-alives { + description + "Configures the keep-alive policy, to proactively + test the aliveness of the SSH/TLS client. An + unresponsive SSH/TLS client will be dropped after + approximately (max-attempts * max-wait) seconds."; + reference + "RFC YYYY: NETCONF Call Home and RESTCONF Call Home, + Section 3.1, item S6"; + leaf max-wait { + type uint16 { + range "1..max"; + } + units seconds; + default 30; + description + "Sets the amount of time in seconds after which + if no data has been received from the SSH/TLS + client, a SSH/TLS-level message will be sent + to test the aliveness of the SSH/TLS client."; + } + leaf max-attempts { + type uint8; + default 3; + description + "Sets the number of sequential keep-alive messages + that can fail to obtain a response from the SSH/TLS + client before assuming the SSH/TLS client is no + longer alive."; + } + } + } + } + case periodic-connection { + container periodic { + presence true; + description + "Periodically connect to the NETCONF client, so that + the NETCONF client may deliver messages pending for + the NETCONF server. The NETCONF client is expected + to close the connection when it is ready to release + it, thus starting the NETCONF server's timer until + next connection."; + leaf idle-timeout { + type uint16; + units "seconds"; + default 300; // five minutes + description + "Specifies the maximum number of seconds that a + 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."; + } + leaf reconnect_timeout { + type uint16 { + range "1..max"; + } + units minutes; + default 60; + description + "The maximum amount of unconnected time the NETCONF + server will wait before re-establishing a connection + to the NETCONF client. The NETCONF server may + initiate a connection before this time if desired + (e.g., to deliver a notification)."; + } + } + } + } + } + container reconnect-strategy { + description + "The reconnection strategy guides how a NETCONF server + reconnects to an NETCONF client, after losing a connection + to it, 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."; + } + } + 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)."; + } + } + } + } + } + + grouping tls-server-grouping { + description + "An augmentation of tls-server-grouping, as defined in the + ietf-tls-server module, to add in cert-maps."; + uses ts:tls-server-grouping { + augment "client-auth" { + container cert-maps { + 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."; + reference + "RFC WWWW: NETCONF over TLS, Section 7"; + } + } + } + } + + grouping address-and-port-grouping { + description + "This grouping is used by both the ssh and tls containers + for listen configuration."; + leaf address { + type inet:ip-address; + description + "The IP address of the interface to listen on. The NETCONF + server will listen on all interfaces if no value is + specified."; + } + leaf port { + type inet:port-number; + description + "The local port number on this interface the NETCONF server + listens on. The NETCONF server will use the IANA-assigned + well-known port if no value is specified."; + } + } + + grouping endpoints-container { + description + "This grouping is used by both the ssh and tls containers + for call-home configurations."; + 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 NETCONF client. + Defining more than one enables high-availability."; + leaf name { + type string; + description + "An arbitrary name for this endpoint."; + } + leaf address { + type inet:host; + mandatory true; + description + "The IP address or hostname of the endpoint. If a + hostname is configured and the DNS resolution results + in more than one IP address, the NETCONF server + will process the IP addresses as if they had been + explicitly configured in place of the hostname."; + } + leaf port { + type inet:port-number; + description + "The IP port for this endpoint. The NETCONF server will + use the IANA-assigned well-known port if no value is + specified."; + } + } + } + } + +} + + +A.5. The RESTCONF Server Model + +A.5.1. Tree Diagram + +module: ietf-restconf-server-new + +--rw restconf-server + +--rw listen {tls-listen}? + | +--rw max-sessions? uint16 + | +--rw endpoint* [name] + | +--rw name string + | +--rw (transport) + | +--:(tls) + | +--rw tls + | +--rw address? inet:ip-address + | +--rw port? inet:port-number + | +--rw certificates + | | +--rw certificate* [name] + | | +--rw name -> /kc:keychain/private-keys/private-key/certificates/certificate/name + | +--rw client-auth + | +--rw trusted-ca-certs? -> /kc:keychain/trusted-certificates/name + | +--rw trusted-client-certs? -> /kc:keychain/trusted-certificates/name + | +--rw cert-maps + | +--rw cert-to-name* [id] + | +--rw id uint32 + | +--rw fingerprint x509c2n:tls-fingerprint + | +--rw map-type identityref + | +--rw name string + +--rw call-home {tls-call-home}? + +--rw restconf-client* [name] + +--rw name string + +--rw (transport) + | +--:(tls) + | +--rw tls + | +--rw endpoints + | | +--rw endpoint* [name] + | | +--rw name string + | | +--rw address inet:host + | | +--rw port? inet:port-number + | +--rw certificates + | | +--rw certificate* [name] + | | +--rw name -> /kc:keychain/private-keys/private-key/certificates/certificate/name + | +--rw client-auth + | +--rw trusted-ca-certs? -> /kc:keychain/trusted-certificates/name + | +--rw trusted-client-certs? -> /kc:keychain/trusted-certificates/name + | +--rw cert-maps + | +--rw cert-to-name* [id] + | +--rw id uint32 + | +--rw fingerprint x509c2n:tls-fingerprint + | +--rw map-type identityref + | +--rw name string + +--rw connection-type + | +--rw (connection-type)? + | +--:(persistent-connection) + | | +--rw persistent! + | | +--rw keep-alives + | | +--rw max-wait? uint16 + | | +--rw max-attempts? uint8 + | +--:(periodic-connection) + | +--rw periodic! + | +--rw reconnect-timeout? uint16 + +--rw reconnect-strategy + +--rw start-with? enumeration + +--rw max-attempts? uint8 + +A.5.2. Example Usage + + TBD + +A.5.3. YANG Model + + This YANG module imports YANG types from [RFC6991] and [RFC7407]. + + file "ietf-restconf-server-new@2015-07-06.yang" + +module ietf-restconf-server-new { + yang-version 1.1; + + namespace "urn:ietf:params:xml:ns:yang:ietf-restconf-server-new"; + prefix "rcserver"; + + import ietf-netconf-acm { + prefix nacm; // RFC 6536 + } + import ietf-inet-types { // RFC 6991 + prefix inet; + } + import ietf-x509-cert-to-name { // RFC 7407 + prefix x509c2n; + } + import ietf-tls-server { // RFC VVVV + prefix ts; + } + organization + "IETF NETCONF (Network Configuration) Working Group"; + + contact + "WG Web: + WG List: + + WG Chair: Mehmet Ersue + + + WG Chair: Mahesh Jethanandani + + + Editor: Kent Watsen + "; + + description + "This module contains a collection of YANG definitions for + configuring RESTCONF 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 VVVV; see + the RFC itself for full legal notices."; + + revision "2015-07-06" { + description + "Initial version"; + reference + "RFC VVVV: NETCONF Server and RESTCONF Server Configuration + Models"; + } + + // Features + + feature tls-listen { + description + "The listen feature indicates that the RESTCONF server + supports opening a port to listen for incoming RESTCONF + client connections."; + reference + "RFC XXXX: RESTCONF Protocol"; + } + + feature tls-call-home { + description + "The call-home feature indicates that the RESTCONF server + supports initiating connections to RESTCONF clients."; + reference + "RFC YYYY: NETCONF Call Home and RESTCONF Call Home"; + } + + feature client-cert-auth { + description + "The client-cert-auth feature indicates that the RESTCONF + server supports the ClientCertificate authentication scheme."; + reference + "RFC ZZZZ: Client Authentication over New TLS Connection"; + } + + // top-level container (groupings below) + container restconf-server { + description + "Top-level container for RESTCONF server configuration."; + + container listen { + description + "Configures listen behavior"; + if-feature tls-listen; + leaf max-sessions { + type uint16; + default 0; // should this be 'max'? + 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 RESTCONF connections on."; + leaf name { + type string; + description + "An arbitrary name for the RESTCONF listen endpoint."; + + } + choice transport { + mandatory true; + description + "Selects between available transports."; + case tls { + container tls { + description + "TLS-specific listening configuration for inbound + connections."; + leaf address { + type inet:ip-address; + description + "The IP address of the interface to listen on. The + RESTCONF server will listen on all interfaces if + no value is specified."; + } + leaf port { + type inet:port-number; + default 443; + description + "The port number the RESTCONF server will listen on."; + } + uses tls-server-grouping; + } + } + } + } + } + + container call-home { + if-feature tls-call-home; + description + "Configures call-home behavior"; + list restconf-client { + key name; + description + "List of RESTCONF clients the RESTCONF server is to + initiate call-home connections to."; + leaf name { + type string; + description + "An arbitrary name for the remote RESTCONF client."; + } + choice transport { + mandatory true; + description + "Selects between TLS and any transports augmented in."; + + case tls { + container tls { + description + "Specifies TLS-specific call-home transport + configuration."; + 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 RESTCONF + client. More than one enables high-availability."; + leaf name { + type string; + description + "An arbitrary name for this endpoint."; + } + leaf address { + type inet:host; + mandatory true; + description + "The IP address or hostname of the endpoint. If + a hostname is configured and the DNS resolution + results in more than one IP address, the RESTCONF + server will process the IP addresses as if they + had been explicitly configured in place of the + hostname."; + } + leaf port { + type inet:port-number; + default 9999; + description + "The IP port for this endpoint. The RESTCONF + server will use the IANA-assigned well-known + port if no value is specified."; + } + } + } + uses tls-server-grouping; + } + } + } + container connection-type { + description + "Indicates the RESTCONF client's preference for how the + RESTCONF server's connection is maintained."; + choice connection-type { + description + "Selects between available connection types."; + case persistent-connection { + container persistent { + presence true; + description + "Maintain a persistent connection to the RESTCONF + client. If the connection goes down, immediately + start trying to reconnect to it, using the + reconnection strategy. + + This connection type minimizes any RESTCONF client + to RESTCONF server data-transfer delay, albeit at + the expense of holding resources longer."; + + container keep-alives { + description + "Configures the keep-alive policy, to proactively + test the aliveness of the TLS client. An + unresponsive TLS client will be dropped after + approximately (max-attempts * max-wait) seconds."; + reference + "RFC YYYY: NETCONF Call Home and RESTCONF Call Home, + Section 3.1, item S6"; + leaf max-wait { + type uint16 { + range "1..max"; + } + units seconds; + default 30; + description + "Sets the amount of time in seconds after which + if no data has been received from the TLS + client, a TLS-level message will be sent to + test the aliveness of the TLS client."; + } + leaf max-attempts { + type uint8; + default 3; + description + "Sets the number of sequential keep-alive messages + that can fail to obtain a response from the TLS + client before assuming the TLS client is no + longer alive."; + } + } + + } + } + case periodic-connection { + container periodic { + presence true; + description + "Periodically connect to the RESTCONF client, so that + the RESTCONF client may deliver messages pending for + the RESTCONF server. The RESTCONF client is expected + to close the connection when it is ready to release + it, thus starting the RESTCONF server's timer until + next connection."; + leaf reconnect-timeout { + type uint16 { + range "1..max"; + } + units minutes; + default 60; + description + "The maximum amount of unconnected time the RESTCONF + server will wait before re-establishing a connection + to the RESTCONF client. The RESTCONF server may + initiate a connection before this time if desired + (e.g., to deliver a notification)."; + } + } + } + } + } + container reconnect-strategy { + description + "The reconnection strategy guides how a RESTCONF server + reconnects to an RESTCONF client, after losing a connection + to it, even if due to a reboot. The RESTCONF 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. RESTCONF + servers SHOULD be able to remember the last + endpoint connected to across reboots."; + } + } + default first-listed; + description + "Specifies which of the RESTCONF client's endpoints the + RESTCONF server should start with when trying to connect + to the RESTCONF client."; + } + leaf max-attempts { + type uint8 { + range "1..max"; + } + default 3; + description + "Specifies the number times the RESTCONF server tries to + connect to a specific endpoint before moving on to the + next endpoint in the list (round robin)."; + } + } + } + } + } + + grouping tls-server-grouping { + description + "An augmentation of tls-server-grouping, as defined in the + ietf-tls-server module, to add in cert-maps."; + uses ts:tls-server-grouping { + augment "client-auth" { + container cert-maps { + 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."; + reference + "RFC WWWW: NETCONF over TLS, Section 7"; + } + } + } + } + +} + + 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 @@ -2212,20 +3958,69 @@ o Updated draft-ietf-netmod-snmp-cfg reference to RFC 7407 (issue #28). o Added description statements for groupings (issue #29). o Added description for braces to tree diagram section (issue #30). o Renamed feature from "rfc6187" to "ssh-x509-certs" (issue #31). +B.7. 06 to 07 + + o Replaced "application" with "NETCONF/RESTCONF client" (issue #32). + + o Reverted back to YANG 1.1 if-feature statements (issue #34). + + o Removed import by revisions (issue #36). + + o Removed groupings only used once (issue #37). + + o Removed upper-bound on hello-timeout, idle-timeout, and max- + sessions (issue #38). + + o Clarified that when no listen address is configured, the NETCONF/ + RESTCONF server will listen on all addresses (issue #41). + + o Update keep-alive reference to new section in Call Home draft + (issue #42). + + o Modified connection-type/persistent/keep-alives/interval-secs + default value, removed the connection-type/periodic/linger-secs + node, and also removed the reconnect-strategy/interval-secs node + (issue #43). + + o Clarified how last-connected reconnection type should work across + reboots (issue #44). + + o Clarified how DNS-expanded hostnames should be processed (issue + #45). + + o Removed text on how to implement keep-alives (now in the call-home + draft) and removed the keep-alive configuration for listen + connections (issue #46). + + o Clarified text for .../periodic-connection/timeout-mins (issue + #47). + + o Fixed description on the "trusted-ca-certs" leaf-list (issue #48). + + o Added optional keychain-based solution in appendix A (issue #49). + + o Fixed description text for the interval-secs leaf (issue #50). + + o moved idle-time into the listen, persistent, and periodic subtrees + (issue #51). + + o put presence statements on containers where it makes sense (issue + #53). + Appendix C. Open Issues Please see: https://github.com/netconf-wg/server-model/issues. Authors' Addresses Kent Watsen Juniper Networks EMail: kwatsen@juniper.net