Network Working Group H. Wang Internet-Draft Huawei Intended status: Standards Track A. Wang Expires: May 7, 2020 China Telecom S. Zhuang Huawei November 04, 2019 Destination-IP-Origin-AS Filter for BGP Flow Specification draft-wang-idr-flowspec-dip-origin-as-filter-01 Abstract This document specifies a new BGP-FS component type to support AS- level filtering. The match field is the origin AS number of the destination IP address that is encoded in the Flowspec NLRI. Requirements Language 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]. 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 https://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 May 7, 2020. Copyright Notice Copyright (c) 2019 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents Wang, et al. Expires May 7, 2020 [Page 1] Internet-Draft Destination-IP-Origin-AS Filter November 2019 (https://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 2. Definitions and Acronyms . . . . . . . . . . . . . . . . . . 2 3. The Flow Specification Encoding for Destination-IP-Origin-AS Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 4. Use Case . . . . . . . . . . . . . . . . . . . . . . . . . . 4 5. Security Considerations . . . . . . . . . . . . . . . . . . . 5 6. IANA . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 7. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 6 8. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 6 9. References . . . . . . . . . . . . . . . . . . . . . . . . . 6 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 6 1. Introduction BGP Flow Specification (BGP-FS) [RFC5575] defines a new BGP NLRI to distribute traffic flow specification rules via BGP ([RFC4271]). BGP-FS policies have a match condition that may be n-tuple match in a policy, and an action that modifies the packet and forwards/drops the packet. Via BGP, new filter rules can be sent to all BGP peers simultaneously without changing router configuration, and the BGP peer can install these routes in the forwarding table. BGP-FS defines Network Layer Reachability Information (NLRI) format used to distribute traffic flow specification rules. NLRI (AFI=1, SAFI=133) is for IPv4 unicast filtering. NLRI (AFI=1, SAFI=134) is for BGP/ MPLS VPN filtering.[I-D.ietf-idr-flowspec-l2vpn][I-D.ietf-idr- flowspec-l2vpn] extends the flow-spec rules for layer 2 Ethernet packets. This document specifies a new BGP-FS component type to support AS- level filtering. The match field is the origin AS number of the destination IP address that is encoded in the Flowspec NLRI. 2. Definitions and Acronyms o FS: Flow Specification o Destination-IP-Origin-AS: The origin AS number of the destination IP address Wang, et al. Expires May 7, 2020 [Page 2] Internet-Draft Destination-IP-Origin-AS Filter November 2019 3. The Flow Specification Encoding for Destination-IP-Origin-AS Filter This document proposes a new flow specification rule that is encoded in the NLRI. The following new component type is defined. o Destination-IP-Origin-AS Type TBD1 - Destination-IP-Origin-AS Encoding: Contains a set of {operator, value} pairs that are used to match the Destination-IP-Origin-AS (i.e. the origin AS number of the destination IP address). The operator byte is encoded as: 0 1 2 3 4 5 6 7 +---+---+---+---+---+---+---+---+ | e | a | len | 0 |lt |gt |eq | +---+---+---+---+---+---+---+---+ Where: e - end-of-list bit. Set in the last {op, value} pair in the list. a - AND bit. If unset, the previous term is logically ORed with the current one. If set, the operation is a logical AND. It MUST be unset in the Destination-IP-Origin-AS filter. lt - less than comparison between data and value. gt - greater than comparison between data and value. eq - equality between data and value. The bits lt, gt, and eq can be combined to produce match the Destination-IP-Origin-AS filter or a range of Destination-IP-Origin- AS filter(e.g. less than AS1 and greater than AS2). The value field is encoded as: 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +---------------------------------------------------------------+ ~ Destination-IP-Origin-AS (4 octets) ~ +---------------------------------------------------------------+ Wang, et al. Expires May 7, 2020 [Page 3] Internet-Draft Destination-IP-Origin-AS Filter November 2019 4. Use Case In AS64597's R1, if the ISP AS64597 wants to redirect all packets from IP Prefix 61 to AS64598, first goto to R3, then forward to AS64598", the ISP can use the traditional method or the method defining in this draft. +---------+ | BGP FS | | Server | +----|----+ | | / / ************/************ IP Prefix 81 * / * IP Prefix 82 IP Prefix 61 * / AS64597 * IP Prefix 83 * / * IP Prefix 84 +-------+ * +---+/ +---+ * +-------+ +AS64596+-------+ R1+---------+ R2|------+AS64598+ +-------+ * +-+-+\ +---+ */ +-------+ * \ |\ / * \ | \ /* IP Prefix 91 * \ | /\* IP Prefix 92 * \ | / \ IP Prefix 93 * \ |/ *\ IP Prefix 94 * \ +-+-+ * \ +-------+ * \-+ R3+------+AS64599+ * +---+ * +-------+ * * ************************* Figure 1: Steering the Traffic Using Flowspec Using the traditional method, the ISP AS64597 needs to setup multiple "Destination Prefix + Source Prefix" rules in Router R1 as following: Wang, et al. Expires May 7, 2020 [Page 4] Internet-Draft Destination-IP-Origin-AS Filter November 2019 +--------------+--------------+-------------------------+ | Destination | Source Prefix| Redirect to IP Nexthop | | Prefix | | | +--------------+--------------+-------------------------+ | IP Prefix 81 | IP Prefix 61 | R3 | +--------------+--------------+-------------------------+ | IP Prefix 82 | IP Prefix 61 | R3 | +--------------+--------------+-------------------------+ | IP Prefix 83 | IP Prefix 61 | R3 | +--------------+--------------+-------------------------+ | IP Prefix 84 | IP Prefix 61 | R3 | +--------------+--------------+-------------------------+ | More... | +--------------+--------------+-------------------------+ Figure 2: Steering the Traffic Using Destination Prefix and Source Prefix Using the method defining in this draft, the ISP AS64597 needs to setup only one "Destination Origin AS + Source Prefix" rule in Router R1 as following: +--------------+--------------+-------------------------+ | Destination | Source Prefix| Redirect to IP Nexthop | | IP Origin AS | | | +--------------+--------------+-------------------------+ | 64598 | IP Prefix 61 | R3 | +--------------+--------------+-------------------------+ Figure 3: Steering the Traffic Using Origin AS and Source Prefix 5. Security Considerations No new security issues are introduced to the BGP protocol by this specification. 6. IANA IANA is requested to a new entry in "Flow Spec component types registry" with the following values: +----------------------------------------------------------+ | Type | RFC or Draft | Description | +----------------------------------------------------------+ | TBD1 | This Draft | Destination-IP-Origin-AS | +----------------------------------------------------------+ Wang, et al. Expires May 7, 2020 [Page 5] Internet-Draft Destination-IP-Origin-AS Filter November 2019 7. Contributors TBD 8. Acknowledgments The authors would like to acknowledge the review and inputs from Gang Yan, Zhenbin Li, Rainbow Wu and Ziqing Cao. 9. References [I-D.ietf-idr-flowspec-l2vpn] Weiguo, H., Eastlake, D., Uttaro, J., Litkowski, S., and S. Zhuang, "BGP Dissemination of L2VPN Flow Specification Rules", draft-ietf-idr-flowspec-l2vpn-11 (work in progress), July 2019. [I-D.ietf-idr-rfc5575bis] Loibl, C., Hares, S., Raszuk, R., McPherson, D., and M. Bacher, "Dissemination of Flow Specification Rules", draft-ietf-idr-rfc5575bis-17 (work in progress), June 2019. [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, . [RFC4271] Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A Border Gateway Protocol 4 (BGP-4)", RFC 4271, DOI 10.17487/RFC4271, January 2006, . [RFC5575] Marques, P., Sheth, N., Raszuk, R., Greene, B., Mauch, J., and D. McPherson, "Dissemination of Flow Specification Rules", RFC 5575, DOI 10.17487/RFC5575, August 2009, . Authors' Addresses Haibo Wang Huawei 156 Beiqing Road Beijing 100095 P.R. China Email: rainsword.wang@huawei.com Wang, et al. Expires May 7, 2020 [Page 6] Internet-Draft Destination-IP-Origin-AS Filter November 2019 Aijun China Telecom Beiqijia Town, Changping District Beijing 102209 P.R. China Email: wangaj3@chinatelecom.cn Shunwan Zhuang Huawei 156 Beiqing Road Beijing 100095 P.R. China Email: zhuangshunwan@huawei.com Wang, et al. Expires May 7, 2020 [Page 7]