idnits 2.17.1 draft-spaghetti-sidrops-rpki-manifest-validation-00.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 : ---------------------------------------------------------------------------- -- The abstract seems to indicate that this document updates RFC6486, but the header doesn't have an 'Updates:' line to match this. Miscellaneous warnings: ---------------------------------------------------------------------------- == The copyright year in the IETF Trust and authors Copyright Line does not match the current year -- The document date (May 3, 2020) is 1453 days in the past. Is this intentional? Checking references for intended status: Informational ---------------------------------------------------------------------------- ** Obsolete normative reference: RFC 6486 (Obsoleted by RFC 9286) Summary: 1 error (**), 0 flaws (~~), 1 warning (==), 2 comments (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Network Working Group J. Snijders 3 Internet-Draft NTT 4 Intended status: Informational May 3, 2020 5 Expires: November 4, 2020 7 A Default Validation Policy for the use of RPKI Manifests in the global 8 Internet Routing System. 9 draft-spaghetti-sidrops-rpki-manifest-validation-00 11 Abstract 13 Manifests are a critical cornerstone to the global Resource Public 14 Key Infrastructure (RPKI). 16 RFC 6486 describes a validation decision tree which introduced the 17 notion of 'local policy', creating space for ambiguity. This 18 ambiguity has led to various RPKI implementations producing different 19 output when presented with the same input, but also leads to severe 20 operational security implications. 22 This document updates RFC 6486 and introduces the notion of a default 23 policy for Manifest validation to encourage harmony between 24 implementations. 26 Requirements Language 28 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 29 "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and 30 "OPTIONAL" in this document are to be interpreted as described in BCP 31 14 [RFC2119] [RFC8174] when, and only when, they appear in all 32 capitals, as shown here. 34 Status of This Memo 36 This Internet-Draft is submitted in full conformance with the 37 provisions of BCP 78 and BCP 79. 39 Internet-Drafts are working documents of the Internet Engineering 40 Task Force (IETF). Note that other groups may also distribute 41 working documents as Internet-Drafts. The list of current Internet- 42 Drafts is at https://datatracker.ietf.org/drafts/current/. 44 Internet-Drafts are draft documents valid for a maximum of six months 45 and may be updated, replaced, or obsoleted by other documents at any 46 time. It is inappropriate to use Internet-Drafts as reference 47 material or to cite them other than as "work in progress." 48 This Internet-Draft will expire on November 4, 2020. 50 Copyright Notice 52 Copyright (c) 2020 IETF Trust and the persons identified as the 53 document authors. All rights reserved. 55 This document is subject to BCP 78 and the IETF Trust's Legal 56 Provisions Relating to IETF Documents 57 (https://trustee.ietf.org/license-info) in effect on the date of 58 publication of this document. Please review these documents 59 carefully, as they describe your rights and restrictions with respect 60 to this document. Code Components extracted from this document must 61 include Simplified BSD License text as described in Section 4.e of 62 the Trust Legal Provisions and are provided without warranty as 63 described in the Simplified BSD License. 65 Table of Contents 67 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 68 2. Suggested Reading . . . . . . . . . . . . . . . . . . . . . . 3 69 3. The Problem . . . . . . . . . . . . . . . . . . . . . . . . . 3 70 4. Update to RFC 6486 . . . . . . . . . . . . . . . . . . . . . 3 71 4.1. Tests for Determining Manifest State . . . . . . . . . . 4 72 5. What to do when the CA's Publication Point is Distrusted . . 5 73 6. TODO . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 74 7. Security Considerations . . . . . . . . . . . . . . . . . . . 5 75 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 5 76 9. References . . . . . . . . . . . . . . . . . . . . . . . . . 5 77 9.1. Normative References . . . . . . . . . . . . . . . . . . 5 78 9.2. Informative References . . . . . . . . . . . . . . . . . 6 79 Appendix A. Acknowledgements . . . . . . . . . . . . . . . . . . 7 80 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 7 82 1. Introduction 84 Manifests [RFC8416] are a critical cornerstone to the global Resource 85 Public Key Infrastructure RPKI [RFC6480]. 87 RFC 6486 describes a validation decision tree which introduced the 88 notion of 'local policy', creating space for ambiguity. This 89 ambiguity has led to various RPKI implementations producing different 90 output when presented with the same input, but also operational 91 security implications. 93 This document updates RFC 6486 and introduces the notion of a global 94 policy for Manifest validation to encourage harmony between 95 implementations. 97 2. Suggested Reading 99 It is assumed that the reader understands BGP, [RFC4271], the RPKI 100 [RFC6480], Route Origin Authorizations (ROAs) [RFC6482], RPKI-based 101 Prefix Validation, [RFC6811], and Origin Validation Clarifications 102 [RFC8481]. 104 3. The Problem 106 It seems there is a mental trap in the RPKI system: contrary to 107 intuition, implementers should focus on validation policies which 108 minimize the number of Validated ROA Payloads (VRPs) at a RPKI cache. 109 If RPKI cache implementers mistreat untrusted network data and 110 'salvage whatever is possible', a number of critical issues are 111 introduced which compromise our ability to deploy RPKI ROV 112 incrementally. Only a single path through the RFC 6486 decision tree 113 is suitable for use in the global Internet system, as such that path 114 is the Default Policy. 116 If a dangerous condition is detected, not only MUST the manifest at 117 the publication point be distrusted, but all VRPs encompassed by the 118 IPAddrBlocks for which authority was delegated towards the 119 Certificate Authority (CA) at the distrusted pulication point be 120 removed from the RP's output. If the result is no VRPs at all (for 121 example because the RPKI subsystem is detected to be compromised at 122 the root), that is a preferred state for the Internet routing system. 123 The alternative is that a compromised RPKI system will permanently 124 disrupt the global Internet routing system. 126 4. Update to RFC 6486 128 This section replaces section 6 of [RFC6486] in its entirety. 130 The goal of an Relying Party (RP) is to determine which signed 131 objects to use for validating assertions about INRs and their use 132 (e.g., which VRPs to use in the construction of route filters). The 133 global Internet routing system is expected to benefit from uniform 134 application of a similar validation policy, as such in the following 135 sections we describe a sequence of tests that the RP MUST perform to 136 determine the manifest state of the given publication point according 137 to the default policy. We then discuss the risks associated with 138 using signed objects in the publication point, given the manifest 139 state; we also provide suitable warning text that SHOULD be placed in 140 a user-accessible log file. Note that if a certificate is deemed 141 unfit for use due to default policy, then any signed object that is 142 validated using this certificate also SHOULD be deemed unfit for use 143 (regardless of the status of the manifest at its own publication 144 point). 146 4.1. Tests for Determining Manifest State 148 For a given publication point, the RP MUST perform the following 149 tests to determine the manifest state of the publication point: 151 1. For each CA using this publication point, select the CA's current 152 manifest (the "current" manifest is the manifest issued by this 153 CA having the highest manifestNumber among all valid manifests, 154 and where manifest validity is defined in Section 4.4 [RFC6486]. 155 If the publication point does not contain a valid manifest, see 156 Section 5. Lacking a valid manifest, the following tests cannot 157 be performed. 159 2. To verify completeness, an RP MUST check that every file at each 160 publication point appears in one and only one current manifest, 161 and that every file listed in a current manifest is published at 162 the same publication point as the manifest. 164 3. If files exist at the publication point that do not appear on any 165 manifest, those can be ignored. 167 4. If files are listed in a manifest that do not appear at the 168 publication point, see Section 5. 170 5. Check that the current time (translated to UTC) is between 171 thisUpdate and nextUpdate. If the current time does not lie 172 within this interval, then see Section 5, but still continue with 173 the following tests. 175 6. Verify that the listed hash value of every file listed in each 176 manifest matches the value obtained by hashing the file at the 177 publication point. If the computed hash value of a file listed 178 on the manifest does not match the hash value contained in the 179 manifest, then see Section 5. 181 7. An RP MUST check that the contents of each current manifest 182 conforms to the manifest's scope constraints, as specified in 183 Section 2. 185 8. If a current manifest contains entries for objects that are not 186 within the scope of the manifest, then the out-of-scope entries 187 SHOULD be disregarded in the context of this manifest. If there 188 is no other current manifest that describes these objects within 189 that other manifest's scope, then see Section 5. 191 For each signed object, if all of the following conditions hold: 193 the manifest for its publication and the associated publication 194 point pass all of the above checks; 196 the signed object is valid; and 198 the manifests for every certificate on the certification path used 199 to validate the signed object and the associated publication 200 points pass all of the above checks; 202 then the RP can conclude that no attack against the repository system 203 has compromised the given signed object, and the signed object MUST 204 be treated as valid (relative to manifest checking). 206 5. What to do when the CA's Publication Point is Distrusted 208 Once the RP has concluded the data at the publication point is 209 distrusted, the RP MUST remove all VRPs encompassed by the 210 IPAddrBlocks for which "right-of-use" authority was delegated to the 211 CA at the distrusted publication from its output, regardless of the 212 Trust Anchors. 214 6. TODO 216 o Mention RIR transfer cases 218 o The case for a most conservative approach: a 'fail-closed' policy 219 on the RPKI plane results in an collective ability to deploy ROV 220 on the shared EBGP plane: as the default remains 'fail open' (aka 221 'pre RPKI world'), operators in turn can deploy 'invalid == 222 reject' policies on their EBGP sessions incrementally. A 223 brilliant strategy, however it strongly depends erring to the side 224 of caution (distrust?) in the validation process. 226 7. Security Considerations 228 ... where to start 230 8. IANA Considerations 232 None 234 9. References 236 9.1. Normative References 238 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 239 Requirement Levels", BCP 14, RFC 2119, 240 DOI 10.17487/RFC2119, March 1997, 241 . 243 [RFC4271] Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A 244 Border Gateway Protocol 4 (BGP-4)", RFC 4271, 245 DOI 10.17487/RFC4271, January 2006, 246 . 248 [RFC6482] Lepinski, M., Kent, S., and D. Kong, "A Profile for Route 249 Origin Authorizations (ROAs)", RFC 6482, 250 DOI 10.17487/RFC6482, February 2012, 251 . 253 [RFC6486] Austein, R., Huston, G., Kent, S., and M. Lepinski, 254 "Manifests for the Resource Public Key Infrastructure 255 (RPKI)", RFC 6486, DOI 10.17487/RFC6486, February 2012, 256 . 258 [RFC6811] Mohapatra, P., Scudder, J., Ward, D., Bush, R., and R. 259 Austein, "BGP Prefix Origin Validation", RFC 6811, 260 DOI 10.17487/RFC6811, January 2013, 261 . 263 [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 264 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, 265 May 2017, . 267 [RFC8416] Ma, D., Mandelberg, D., and T. Bruijnzeels, "Simplified 268 Local Internet Number Resource Management with the RPKI 269 (SLURM)", RFC 8416, DOI 10.17487/RFC8416, August 2018, 270 . 272 [RFC8481] Bush, R., "Clarifications to BGP Origin Validation Based 273 on Resource Public Key Infrastructure (RPKI)", RFC 8481, 274 DOI 10.17487/RFC8481, September 2018, 275 . 277 9.2. Informative References 279 [RFC6480] Lepinski, M. and S. Kent, "An Infrastructure to Support 280 Secure Internet Routing", RFC 6480, DOI 10.17487/RFC6480, 281 February 2012, . 283 Appendix A. Acknowledgements 285 The authors wish to thank Rob Austein, Geoff Huston, Stephen Kent, 286 Matt Lepinski, Martin Hoffman, Randy Bush, and Theo de Raadt for 287 their insights and contributions which helped create this document. 289 Author's Address 291 Job Snijders 292 NTT Ltd. 293 Theodorus Majofskistraat 100 294 Amsterdam 1065 SZ 295 The Netherlands 297 Email: job@ntt.net