idnits 2.17.1 draft-ietf-idr-as0-03.txt: Checking boilerplate required by RFC 5378 and the IETF Trust (see https://trustee.ietf.org/license-info): ---------------------------------------------------------------------------- No issues found here. Checking nits according to https://www.ietf.org/id-info/1id-guidelines.txt: ---------------------------------------------------------------------------- No issues found here. Checking nits according to https://www.ietf.org/id-info/checklist : ---------------------------------------------------------------------------- No issues found here. Miscellaneous warnings: ---------------------------------------------------------------------------- == The copyright year in the IETF Trust and authors Copyright Line does not match the current year -- The document date (January 16, 2012) is 4478 days in the past. Is this intentional? Checking references for intended status: Proposed Standard ---------------------------------------------------------------------------- (See RFCs 3967 and 4897 for information about using normative references to lower-maturity documents in RFCs) == Missing Reference: 'RFC5668' is mentioned on line 212, but not defined == Outdated reference: A later version (-19) exists of draft-ietf-idr-error-handling-00 == Outdated reference: A later version (-07) exists of draft-ietf-idr-rfc4893bis-04 Summary: 0 errors (**), 0 flaws (~~), 4 warnings (==), 1 comment (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 idr W. Kumari 3 Internet-Draft Google 4 Intended status: Standards Track R. Bush 5 Expires: July 19, 2012 Internet Initiative Japan 6 H. Schiller 7 Verizon 8 K. Patel 9 Cisco Systems 10 January 16, 2012 12 Codification of AS 0 processing. 13 draft-ietf-idr-as0-03 15 Abstract 17 This document proscribes the use of AS 0 in BGP OPEN and AS_PATH / 18 AS4_PATH BGP attribute. 20 Status of this Memo 22 This Internet-Draft is submitted in full conformance with the 23 provisions of BCP 78 and BCP 79. 25 Internet-Drafts are working documents of the Internet Engineering 26 Task Force (IETF). Note that other groups may also distribute 27 working documents as Internet-Drafts. The list of current Internet- 28 Drafts is at http://datatracker.ietf.org/drafts/current/. 30 Internet-Drafts are draft documents valid for a maximum of six months 31 and may be updated, replaced, or obsoleted by other documents at any 32 time. It is inappropriate to use Internet-Drafts as reference 33 material or to cite them other than as "work in progress." 35 This Internet-Draft will expire on July 19, 2012. 37 Copyright Notice 39 Copyright (c) 2012 IETF Trust and the persons identified as the 40 document authors. All rights reserved. 42 This document is subject to BCP 78 and the IETF Trust's Legal 43 Provisions Relating to IETF Documents 44 (http://trustee.ietf.org/license-info) in effect on the date of 45 publication of this document. Please review these documents 46 carefully, as they describe your rights and restrictions with respect 47 to this document. Code Components extracted from this document must 48 include Simplified BSD License text as described in Section 4.e of 49 the Trust Legal Provisions and are provided without warranty as 50 described in the Simplified BSD License. 52 Table of Contents 54 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 55 1.1. Requirements notation . . . . . . . . . . . . . . . . . . . 3 56 2. Behavior . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 57 3. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 4 58 4. Security Considerations . . . . . . . . . . . . . . . . . . . . 4 59 5. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 4 60 6. References . . . . . . . . . . . . . . . . . . . . . . . . . . 4 61 6.1. Normative References . . . . . . . . . . . . . . . . . . . 4 62 6.2. Informative References . . . . . . . . . . . . . . . . . . 5 63 Appendix A. Changes / Author Notes. . . . . . . . . . . . . . . . 5 64 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 6 66 1. Introduction 68 Autonomous System 0 is listed in the IANA Autonomous System Number 69 Registry as "Reserved - May be use to identify non-routed networks" 70 ([IANA.AS_Numbers]). 72 [I-D.ietf-sidr-iana-objects] specifies that AS number zero in a ROA 73 is used to mark an NLRI which is to be marked as Invalid. 75 No clear statement that AS 0 was proscribed could be found in any BGP 76 specification. 78 As at least two implementations discard routes containing AS 0 (and 79 to allow approaches such as the above) this document codifies this 80 behavior. 82 1.1. Requirements notation 84 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 85 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 86 document are to be interpreted as described in [RFC2119]. 88 2. Behavior 90 A BGP speaker MUST NOT originate or propagate a route with an AS 91 number of zero in the AS_PATH, AS4_PATH, AGGREGATOR or AS4_AGGREGATOR 92 attributes. 94 An UPDATE message that contains the AS number of zero in the AS_PATH 95 or AS4_PATH attribute MUST be considered as malformed, and be handled 96 by the procedures specified in [I-D.ietf-idr-error-handling]. 98 An UPDATE message that contains the AS number of zero in the 99 AGGREGATOR or AS4_AGGREGATOR attribute MUST be considered as 100 malformed, and be handled by the procedures specified in 101 [I-D.ietf-idr-rfc4893bis]. 103 If a BGP speaker receives zero as the peer AS in an OPEN message, it 104 MUST abort the connection and send a NOTIFICATION with Error Code 105 "OPEN Message Error" and subcode "Bad Peer AS" (see [RFC4271] Section 106 6.2). A router MUST NOT initiate a connection claiming to be AS 107 number zero. 109 Authors of future protocol extensions that carry the Autonomous 110 System number are encouraged keep in mind that AS number zero is 111 reserved and to provide clear direction on how to handle AS number 112 zero. 114 3. IANA Considerations 116 The IANA is requested to update the Reference for number 0 in the 117 "Autonomous System (AS) Numbers" registry to reference this document. 119 4. Security Considerations 121 By allowing resource holders to say that AS 0 is the only valid 122 origin for a route, we allow them to state that a particular address 123 resource is not in use. By ensuring that all implementations that 124 see AS 0 in a route ignore that route, we prevent a malicious party 125 from announcing routes containing AS 0 in an attempt to hijack those 126 resources. 128 In addition, by standardizing the behavior upon reception of an 129 AS_PATH (or AS4_PATH) containing AS 0, this document makes the 130 behavior better defined, and security gotchas often lurk in the 131 undefined spaces. 133 5. Acknowledgements 135 The authors wish to thank Enke Chen, Brian Dickson, Bruno Decraene, 136 Robert Raszuk, Jakob Heitz, Danny McPherson, Chris Morrow, iLya, John 137 Scudder, Jeff Tantsura, Daniel Ginsburg and Susan Hares. Apologies 138 to those we may have missed, it was not intentional. 140 6. References 142 6.1. Normative References 144 [I-D.ietf-idr-error-handling] 145 Scudder, J., Chen, E., Mohapatra, P., and K. Patel, 146 "Revised Error Handling for BGP UPDATE Messages", 147 draft-ietf-idr-error-handling-00 (work in progress), 148 November 2011. 150 [I-D.ietf-idr-rfc4893bis] 151 Vohra, Q. and E. Chen, "BGP Support for Four-octet AS 152 Number Space", draft-ietf-idr-rfc4893bis-04 (work in 153 progress), July 2011. 155 [IANA.AS_Numbers] 156 IANA, "Autonomous System (AS) Numbers", 157 . 159 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 160 Requirement Levels", BCP 14, RFC 2119, March 1997. 162 [RFC4271] Rekhter, Y., Li, T., and S. Hares, "A Border Gateway 163 Protocol 4 (BGP-4)", RFC 4271, January 2006. 165 6.2. Informative References 167 [I-D.ietf-sidr-iana-objects] 168 Manderson, T., Vegoda, L., and S. Kent, "RPKI Objects 169 issued by IANA", draft-ietf-sidr-iana-objects-03 (work in 170 progress), May 2011. 172 Appendix A. Changes / Author Notes. 174 [RFC Editor: Please remove this section before publication ] 176 Draft accepted as IDR Doc, notes reset. Please see notes for 177 draft-wkumari-idr-as0.xml for prior comments. 179 Changes -00. 181 o Added AS4_PATH -- Robert Raszuk. 182 o Change "bgp listener" to "bgp speaker" -- Enke Chen 183 o Consistent use of AS_PATH (v., AS-PATH and AS PATH) -- Danny 184 McPherson 185 o New text for Sec 2 P1 -- Enke / Keyur / Scudder, 186 http://www.ietf.org/mail-archive/web/idr/current/msg05786.html 187 o I made a boo boo -- I had the file open in 2 editors, made changes 188 in one and overwrote them by saving on the other, then checked the 189 broken one into SVN. Apologies to all whose comments I may have 190 missed... 192 Changes -01 194 o The WG thread 195 http://www.ietf.org/mail-archive/web/idr/current/msg05685.html 196 showed a very strong preference for separating the error 197 definition and handling -- the chairs also showed a prefernce to 198 Publish this and point to the error handling that Enke will write. 199 o The originally suggested text ("An UPDATE message that contains 200 the AS number of zero in the AS-PATH attribute MUST be...") only 201 referenced the AS-PATH, readded AS4_PATH, *AGGREGATOR as suggested 202 by Robert Raszak and Danny. 204 Changes -02 205 o Fixed the reference for *AGGREGATOR. This required breaking it 206 out into two sentences / clauses. 207 o Added text on other places where an AS can show up (e.g: "4-Octet 208 AS specific Extended Community" [RFC5668]) -- thanks to Keyur. 210 Changes - 03 211 o Removed text on other places where an AS can show up (e.g: 212 "4-Octet AS specific Extended Community" [RFC5668]). 213 o Added *very* generic "Authors of future protocol extensions..." 214 text 216 Authors' Addresses 218 Warren Kumari 219 Google 220 1600 Amphitheatre Parkway 221 Mountain View, CA 94043 222 US 224 Email: warren@kumari.net 226 Randy Bush 227 Internet Initiative Japan 228 5147 Crystal Springs 229 Bainbridge Island, WA 98110 230 US 232 Email: randy@psg.com 234 Heather Schiller 235 Verizon 236 22001 Loudoun County Parkway 237 Ashburn 20147 238 US 240 Email: heather.schiller@verizon.com 241 Keyur Patel 242 Cisco Systems 243 170 W. Tasman Drive 244 San Jose, CA 95134 245 USA 247 Phone: 248 Fax: 249 Email: keyupate@cisco.com 250 URI: