NETCONF Working Group K. Watsen Internet-Draft Juniper Networks Intended status: Standards Track July 8, 2016 Expires: January 9, 2017 TLS Client and Server Models draft-ietf-netconf-tls-client-server-00 Abstract This document defines two YANG modules, one defines groupings for a generic TLS client and the other defines groupings for a generic TLS server. It is intended that these groupings will be used by applications using the TLS protocol. 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. No other RFC Editor instructions are specified elsewhere in this document. This document contains references to other drafts in progress, both in the Normative References section, as well as in body text throughout. Please update the following references to reflect their final RFC assignments: o draft-ietf-netconf-system-keychain Artwork in this document contains shorthand references to drafts in progress. Please apply the following replacements: o "XXXX" --> the assigned RFC value for this draft o "YYYY" --> the assigned RFC value for draft-ietf-netconf-system- keychain Artwork in this document contains placeholder values for the date of publication of this draft. Please apply the following replacement: o "2016-07-08" --> the publication date of this draft The following two Appendix sections are to be removed prior to publication: o Appendix A. Change Log Watsen Expires January 9, 2017 [Page 1] Internet-Draft TLS Client and Server Models July 2016 o Appendix B. Open Issues Status of This Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at http://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." This Internet-Draft will expire on January 9, 2017. Copyright Notice Copyright (c) 2016 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 . . . . . . . . . . . . . . . . . . . . . . . . 3 1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3 1.2. Tree Diagrams . . . . . . . . . . . . . . . . . . . . . . 3 2. The TLS Client Model . . . . . . . . . . . . . . . . . . . . 4 2.1. Tree Diagram . . . . . . . . . . . . . . . . . . . . . . 4 2.2. Example Usage . . . . . . . . . . . . . . . . . . . . . . 5 2.3. YANG Model . . . . . . . . . . . . . . . . . . . . . . . 5 3. The TLS Server Model . . . . . . . . . . . . . . . . . . . . 7 3.1. Tree Diagram . . . . . . . . . . . . . . . . . . . . . . 7 3.2. Example Usage . . . . . . . . . . . . . . . . . . . . . . 8 3.3. YANG Model . . . . . . . . . . . . . . . . . . . . . . . 9 4. Security Considerations . . . . . . . . . . . . . . . . . . . 12 Watsen Expires January 9, 2017 [Page 2] Internet-Draft TLS Client and Server Models July 2016 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12 5.1. The IETF XML Registry . . . . . . . . . . . . . . . . . . 12 5.2. The YANG Module Names Registry . . . . . . . . . . . . . 13 6. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 13 7. References . . . . . . . . . . . . . . . . . . . . . . . . . 13 7.1. Normative References . . . . . . . . . . . . . . . . . . 13 7.2. Informative References . . . . . . . . . . . . . . . . . 14 Appendix A. Change Log . . . . . . . . . . . . . . . . . . . . . 15 A.1. server-model-09 to 00 . . . . . . . . . . . . . . . . . . 15 Appendix B. Open Issues . . . . . . . . . . . . . . . . . . . . 15 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 15 1. Introduction This document defines two YANG [RFC6020] modules, one defines groupings for a generic TLS client and the other defines groupings for a generic TLS server (TLS is defined in [RFC5246]). It is intended that these groupings will be used by applications using the TLS protocol. For instance, these groupings could be used to help define the data model for an HTTPS [RFC2818] server or a NETCONF over TLS [RFC7589] based server. The two YANG modules in this document each define two groupings. One grouping defines everything other than what's needed for the TCP [RFC793] protocol layer. The other grouping uses the first grouping while adding TCP layer specifics (e.g., addresses to connect to, ports to listen on, etc.). This separation is done in order to enable applications the opportunity to define their own strategy for how the underlying TCP connection is established. For instance, applications supporting NETCONF Call Home [draft-ietf-netconf-call-home] could use the first grouping for the TLS parts it provides, while adding data nodes for the reversed TCP layer. 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 this document. The meaning of the symbols in these diagrams is as follows: o Brackets "[" and "]" enclose list keys. Watsen Expires January 9, 2017 [Page 3] Internet-Draft TLS Client and Server Models July 2016 o Braces "{" and "}" enclose feature names, and indicate that the named feature must be present for the subtree to be present. o Abbreviations before data node names: "rw" means configuration (read-write) and "ro" state data (read-only). o Symbols after data node names: "?" means an optional node, "!" means a presence container, and "*" denotes a list and leaf-list. o Parentheses enclose choice and case nodes, and case nodes are also marked with a colon (":"). o Ellipsis ("...") stands for contents of subtrees that are not shown. 2. The TLS Client Model EDITOR NOTE: Please ignore this section, it is incomplete. The TLS client model presented in this section contains two YANG groupings, one for a client that initiates the underlying TCP connection and another for a client that has had the TCP connection opened for it already (e.g., call home). Both of these groupings reference data nodes defined by the System Keychain model [draft-ietf-netconf-system-keychain]. For instance, a reference to the keychain model is made to indicate which trusted CA certificate a client should use to authenticate the server's certificate. 2.1. Tree Diagram The following tree diagram presents the data model for the two groupings defined in the ietf-tls-client module. module: ietf-tls-client groupings: initiating-tls-client-grouping +---- some-TBD-tcp-client-stuff? string +---- some-TBD-tls-client-stuff? string non-initiating-tls-client-grouping +---- some-TBD-tls-client-stuff? string Watsen Expires January 9, 2017 [Page 4] Internet-Draft TLS Client and Server Models July 2016 2.2. Example Usage This section shows how it would appear if the initiating-tls-client- grouping were populated with some data. This example is consistent with the examples presented in Section 2.2 of [draft-ietf-netconf-system-keychain]. FIXME 2.3. YANG Model This YANG module has a normative references to [RFC6991] and [draft-ietf-netconf-system-keychain]. file "ietf-tls-client@2016-07-08.yang" // Editor's Note: // This module is incomplete at this time. Below is // just a skeleton so there's something in the draft. // Please ignore this module for now! module ietf-tls-client { yang-version 1.1; namespace "urn:ietf:params:xml:ns:yang:ietf-tls-client"; prefix "tlsc"; /* import ietf-inet-types { prefix inet; reference "RFC 6991: Common YANG Data Types"; } import ietf-system-keychain { prefix kc; reference "RFC YYYY: System Keychain Model"; } */ organization "IETF NETCONF (Network Configuration) Working Group"; contact "WG Web: WG List: WG Chair: Mehmet Ersue Watsen Expires January 9, 2017 [Page 5] Internet-Draft TLS Client and Server Models July 2016 WG Chair: Mahesh Jethanandani Editor: Kent Watsen "; description "This module defines a reusable grouping for a TLS client that can be used as a basis for specific TLS client 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 XXXX; see the RFC itself for full legal notices."; revision "2016-07-08" { description "Initial version"; reference "RFC XXXX: TLS Client and Server Models"; } grouping initiating-tls-client-grouping { description "A reusable grouping for a TLS client that initiates the underlying TCP transport connection."; leaf some-TBD-tcp-client-stuff { type string; description ""; } uses non-initiating-tls-client-grouping; } grouping non-initiating-tls-client-grouping { description "A reusable grouping for a TLS client that does not initiate the underlying TCP transport connection."; Watsen Expires January 9, 2017 [Page 6] Internet-Draft TLS Client and Server Models July 2016 leaf some-TBD-tls-client-stuff { type string; description ""; } } } 3. The TLS Server Model The TLS server model presented in this section contains two YANG groupings, one for a server that opens a socket to accept TCP connections and another for a server that has had the TCP connection opened for it already (e.g., inetd). Both of these groupings reference data nodes defined by the System Keychain model [draft-ietf-netconf-system-keychain]. For instance, a reference to the keychain model is made to indicate the certificate a server should present. 3.1. Tree Diagram The following tree diagram presents the data model for the two groupings defined in the ietf-tls-server module. Watsen Expires January 9, 2017 [Page 7] Internet-Draft TLS Client and Server Models July 2016 module: ietf-tls-server groupings: listening-tls-server-grouping +---- address? inet:ip-address +---- port? inet:port-number +---- certificates | +---- certificate* [name] | +---- name? -> /kc:keychain/private-keys/private-key/certi ficate-chains/certificate-chain/name +---- client-auth +---- trusted-ca-certs? -> /kc:keychain/trusted-certifica tes/name +---- trusted-client-certs? -> /kc:keychain/trusted-certifica tes/name non-listening-tls-server-grouping +---- certificates | +---- certificate* [name] | +---- name? -> /kc:keychain/private-keys/private-key/certi ficate-chains/certificate-chain/name +---- client-auth +---- trusted-ca-certs? -> /kc:keychain/trusted-certifica tes/name +---- trusted-client-certs? -> /kc:keychain/trusted-certifica tes/name 3.2. Example Usage This section shows how it would appear if the listening-tls-server- grouping were populated with some data. This example is consistent with the examples presented in Section 2.2 of [draft-ietf-netconf-system-keychain]. Watsen Expires January 9, 2017 [Page 8] Internet-Draft TLS Client and Server Models July 2016 6513 ex-key-sect571r1-cert deployment-specific-ca-certs explicitly-trusted-client-certs 3.3. YANG Model This YANG module has a normative references to [RFC6991], and [draft-ietf-netconf-system-keychain]. file "ietf-tls-server@2016-07-08.yang" module ietf-tls-server { yang-version 1.1; namespace "urn:ietf:params:xml:ns:yang:ietf-tls-server"; prefix "tlss"; import ietf-inet-types { prefix inet; reference "RFC 6991: Common YANG Data Types"; } import ietf-system-keychain { prefix kc; reference "RFC YYYY: System Keychain Model"; } organization "IETF NETCONF (Network Configuration) Working Group"; contact Watsen Expires January 9, 2017 [Page 9] Internet-Draft TLS Client and Server Models July 2016 "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 XXXX; see the RFC itself for full legal notices."; revision "2016-07-08" { description "Initial version"; reference "RFC XXXX: TLS Client and Server Models"; } // grouping grouping non-listening-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 in its Certificate message, as defined in Section 7.4.2 in RRC 5246."; Watsen Expires January 9, 2017 [Page 10] Internet-Draft TLS Client and Server Models July 2016 reference "RFC 5246: The Transport Layer Security (TLS) Protocol Version 1.2"; 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:certificate-chains/kc:certificate-chain/" + "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."; } Watsen Expires January 9, 2017 [Page 11] Internet-Draft TLS Client and Server Models July 2016 } } grouping listening-tls-server-grouping { description "A reusable grouping for a TLS server that can be used as a basis for specific TLS server instances."; leaf address { type inet:ip-address; description "The IP address of the interface to listen on. The TLS server will listen on all interfaces if no value is specified. Please note that some addresses have special meanings (e.g., '0.0.0.0' and '::')."; } leaf port { type inet:port-number; description "The local port number on this interface the TLS server listens on. When this grouping is used, it is RECOMMENDED that refine statement is used to either set a default port value or to set mandatory true."; } uses non-listening-tls-server-grouping; } } 4. Security Considerations 5. IANA Considerations 5.1. The IETF XML Registry This document registers two URIs in the IETF XML registry [RFC2119]. Following the format in [RFC3688], the following registrations are requested: Watsen Expires January 9, 2017 [Page 12] Internet-Draft TLS Client and Server Models July 2016 URI: urn:ietf:params:xml:ns:yang:ietf-tls-client Registrant Contact: The NETCONF WG of the IETF. XML: N/A, the requested URI is an XML namespace. URI: urn:ietf:params:xml:ns:yang:ietf-tls-server Registrant Contact: The NETCONF WG of the IETF. XML: N/A, the requested URI is an XML namespace. 5.2. The YANG Module Names Registry This document registers two YANG modules in the YANG Module Names registry [RFC6020]. Following the format in [RFC6020], the the following registrations are requested: name: ietf-tls-client namespace: urn:ietf:params:xml:ns:yang:ietf-tls-client prefix: tlsc reference: RFC XXXX name: ietf-tls-server namespace: urn:ietf:params:xml:ns:yang:ietf-tls-server prefix: tlss reference: RFC XXXX 6. 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, Juergen Schoenwaelder, Phil Shafer, Sean Turner, and Bert Wijnen. 7. References 7.1. Normative References [draft-ietf-netconf-system-keychain] Watsen, K., "System Keychain Model", draft-ieft-netconf- system-keychain-00 (work in progress), 2016, . [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, . Watsen Expires January 9, 2017 [Page 13] Internet-Draft TLS Client and Server Models July 2016 [RFC6020] Bjorklund, M., Ed., "YANG - A Data Modeling Language for the Network Configuration Protocol (NETCONF)", RFC 6020, DOI 10.17487/RFC6020, October 2010, . [RFC6991] Schoenwaelder, J., Ed., "Common YANG Data Types", RFC 6991, DOI 10.17487/RFC6991, July 2013, . [RFC7589] Badra, M., Luchuk, A., and J. Schoenwaelder, "Using the NETCONF Protocol over Transport Layer Security (TLS) with Mutual X.509 Authentication", RFC 7589, DOI 10.17487/RFC7589, June 2015, . 7.2. Informative References [draft-ietf-netconf-call-home] Watsen, K., "NETCONF Call Home and RESTCONF Call Home", draft-ieft-netconf-call-home-17 (work in progress), 2015, . [RFC2818] Rescorla, E., "HTTP Over TLS", RFC 2818, DOI 10.17487/RFC2818, May 2000, . [RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688, DOI 10.17487/RFC3688, January 2004, . [RFC5246] Dierks, T. and E. Rescorla, "The Transport Layer Security (TLS) Protocol Version 1.2", RFC 5246, DOI 10.17487/RFC5246, August 2008, . [RFC793] Postel, J., "TRANSMISSION CONTROL PROTOCOL", STD 7, September 1981, . Watsen Expires January 9, 2017 [Page 14] Internet-Draft TLS Client and Server Models July 2016 Appendix A. Change Log A.1. server-model-09 to 00 o This draft was split out from draft-ietf-netconf-server-model-09. o Noted that '0.0.0.0' and '::' might have special meanings. Appendix B. Open Issues Please see: https://github.com/netconf-wg/tls-client-server/issues. Author's Address Kent Watsen Juniper Networks EMail: kwatsen@juniper.net Watsen Expires January 9, 2017 [Page 15]