PCE working group D. Lopez Internet-Draft Telefonica I+D Intended status: Standards Track Q. Wu Expires: September 29, 2017 D. Dhody Z. Wang Huawei D. King Old Dog Consulting March 28, 2017 IGP extension for PCEP security capability support in the PCE discovery draft-wu-pce-discovery-pceps-support-07 Abstract When a Path Computation Element (PCE) is a Label Switching Router (LSR) participating in the Interior Gateway Protocol (IGP), or even a server participating in IGP, its presence and path computation capabilities can be advertised using IGP flooding. The IGP extensions for PCE discovery (RFC 5088 and RFC 5089) define a method to advertise path computation capabilities using IGP flooding for OSPF and IS-IS respectively. However these specifications lack a method to advertise PCEP security (e.g., Transport Layer Security(TLS),TCP Authentication Option (TCP-AO)) support capability. This document proposes new capability flag bits for PCE-CAP-FLAGS sub- TLV that can be announced as attribute in the IGP advertisement to distribute PCEP security support information. 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 September 29, 2017 Lopez, et al. Expires September 29, 2017 [Page 1] Internet-Draft IGP discovery for PCEP Security March 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 . . . . . . . . . . . . . . . . . . . . . . . . 2 2. Conventions used in this document . . . . . . . . . . . . . . 3 3. IGP extension for PCEP security capability support . . . . . 3 3.1. Use of PCEP security capability support for PCE discovery 4 4. Backward Compatibility Consideration . . . . . . . . . . . . 4 5. Management Considerations . . . . . . . . . . . . . . . . . . 4 6. Security Considerations . . . . . . . . . . . . . . . . . . . 4 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 4 8. References . . . . . . . . . . . . . . . . . . . . . . . . . 5 8.1. Normative References . . . . . . . . . . . . . . . . . . 5 8.2. Informative References . . . . . . . . . . . . . . . . . 5 Appendix A. Appendix A: No MD5 Capability Support . . . . . . . 5 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 6 1. Introduction As described in [RFC5440], PCEP communication privacy is one importance issue, as an attacker that intercepts a Path Computation Element (PCE) message could obtain sensitive information related to computed paths and resources. Among the possible solutions mentioned in these documents, Transport Layer Security (TLS) [RFC5246] provides support for peer authentication, and message encryption and integrity while TCP Authentication Option (TCP-AO) offer significantly improved security for applications using TCP. In order for a Path Computation Client(PCC) to begin a connection with a PCE server using TLS or TCP- AO, PCC SHOULD know whether PCE server supports TLS or TCP-AO as a secure transport. Lopez, et al. Expires February 12, 2017 [Page 2] Internet-Draft IGP discovery for PCEP Security August 2016 [RFC5088] and [RFC5089] define a method to advertise path computation capabilities using IGP flooding for OSPF and IS-IS respectively. However [RFC5088] and [RFC5089] lacks a method to advertise PCEP security (e.g., TLS) support capability. This document proposes new capability flag bits for PCE-CAP-FLAGS sub- TLV that can be announced as attributes in the IGP advertisement (defined in [RFC5088] and [RFC5089]) to distribute PCEP security support information. 2. Conventions used in this document The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in RFC2119 [RFC2119]. 3. IGP extension for PCEP security capability support The PCE-CAP-FLAGS sub-TLV is defined in section 4.5 of [RFC5088] and [RFC5089] as an optional sub-TLV used to advertise PCE capabilities. In this section, we extend the PCE-CAP-FLAGS sub-TLV to include the capability and indications that are described for PCEP security (e.g., TLS) support in the current document. In the PCE-CAP-FLAGS sub-TLV defined in [RFC5088] and [RFC5089], nine capability flags defined in [RFC5088] (as per [RFC4657]) and two capability flags defined [RFC5557], [RFC6006] are included and follows the following format: o TYPE: 5 o LENGTH: Multiple of 4 o VALUE: This contains an array of units of 32 bit flags with the most significant bit as 0. Each bit represents one PCE capability. and the processing rule of these flag bits are defined in [RFC5088] and [RFC5089]. In this document, we define two new capability flag bits that indicate TCP Authentication Option (TCP-AO) support, PCEP over TLS support respectively as follows: Bit Capability Description xx TCP AO Support xx PCEP over TLS support Lopez, et al. Expires September 29, 2017 [Page 3] Internet-Draft IGP discovery for PCEP Security March 2017 3.1. Use of PCEP security capability support for PCE discovery TCP-AO, PCEP over TLS support flag bits are advertised using IGP flooding. o PCE supports TCP-AO: IGP advertisement SHOULD include TCP-AO support flag bit. o PCE supports TLS: IGP advertisement SHOULD include PCEP over TLS support flag bit. If PCE supports multiple security mechanisms, it SHOULD include all corresponding flag bits in IGP advertisement. If the client is looking for connecting with PCE server with TCP-AO support, the client MUST check if TCP-AO support flag bit in the PCE- CAP-FLAGS sub-TLV is set. If not, the client SHOULD NOT consider this PCE. If the client is looking for connecting with PCE server using TLS, the client MUST check if PCEP over TLS support flag bit in the PCE-CAP-FLAGS sub-TLV is set. If not, the client SHOULD NOT consider this PCE. 4. Backward Compatibility Consideration An LSR that does not support the new IGP PCE capability bits specified in this document silently ignores those bits. IGP extensions defined in this document do not introduce any new interoperability issues. 5. Management Considerations A configuration option may be provided for advertising and withdrawing PCE security capability via IGP. 6. Security Considerations This document raises no new security issues beyond those described in [RFC5088] and [RFC5089]. 7. IANA Considerations IANA is requested to allocate a new bit in "PCE Security Capability Flags" registry for PCEP Security support capability. Bit Meaning Reference xx TCP-AO Support [This.I.D] xx PCEP over TLS support [This.I.D] Lopez, et al. Expires September 29, 2017 [Page 4] Internet-Draft IGP discovery for PCEP Security March 2017 8. References 8.1. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", March 1997. [RFC5088] Le Roux, JL., "OSPF Protocol Extensions for Path Computation Element (PCE) Discovery", RFC 5088, January 2008. [RFC5089] Le Roux, JL., "IS-IS Protocol Extensions for Path Computation Element (PCE) Discovery", RFC 5089, January 2008. 8.2. Informative References [RFC4657] Ash, J. and J. Le Roux, "Path Computation Element (PCE) Communication Protocol Generic Requirements", RFC 4657, September 2006. [RFC5246] Dierks, T., "The Transport Layer Security (TLS) Protocol Version 1.2", RFC 5246, August 2008. [RFC5440] Le Roux, JL., "Path Computation Element (PCE) Communication Protocol (PCEP)", RFC 5440, March 2009. [RFC5557] Lee, Y., Le Roux, JL., King, D., and E. Oki, "Path Computation Element Communication Protocol (PCEP) Requirements and Protocol Extensions in Support of Global Concurrent Optimization", RFC 5557, July 2009. [RFC6006] Zhao, Q., King, D., Verhaeghe, F., Takeda, T., Ali, Z., and J. Meuric, "Extensions to the Path Computation Element Communication Protocol (PCEP) for Point-to-Multipoint Traffic Engineering Label Switched Paths", RFC 6006, September 2010. Appendix A. Appendix A: No MD5 Capability Support To be compliant with Section 10.2 of RFC5440, this document doesn't consider to add capability for TCP-MD5. Therefore by default, PCEP Speaker in communication supports capability for TCP-MD5 (See section 10.2, [RFC5440] ). A method to advertise TCP-MD5 Capability support using IGP flooding is not required. If the client is looking for connecting with PCE server with other Security capability support (e.g., TLS support) than TCP-MD5, the client MUST check if flag bit Lopez, et al. Expires September 29, 2017 [Page 5] Internet-Draft IGP discovery for PCEP Security March 2017 in the PCE- CAP-FLAGS sub-TLV for specific capability is set (See section 3.1). Authors' Addresses Diego R. Lopez Telefonica I+D Spain Email: diego.r.lopez@telefonica.com Qin Wu Huawei Technologies 12 Mozhou East Road, Jiangning District Nanjing, Jiangsu 210012 China Email: bill.wu@huawei.com Dhruv Dhody Huawei Technologies Divyashree Techno Park, Whitefield Bangalore, Karnataka 560037 India Email: dhruv.ietf@gmail.com Michael Wang Huawei 12 Mozhou East Road, Jiangning District Nanjing, Jiangsu 210012 China Email: wangzitao@huawei.com Daniel King Old Dog Consulting UK Email: daniel@olddog.co.uk