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Please use uppercase 'NOT' together with RFC 2119 keywords (if that is what you mean). Found 'MUST not' in this paragraph: 5. The CURRENT CA will generate new certificates for all existing subordinate CA and EE certificates, and publish those products in the same repository publication point and with the same repository publication point name as the previous OLD subordinate CA and EE certificates. The keys in these reissued certificates MUST not change. -- The document seems to lack a disclaimer for pre-RFC5378 work, but may have content which was first submitted before 10 November 2008. If you have contacted all the original authors and they are all willing to grant the BCP78 rights to the IETF Trust, then this is fine, and you can ignore this comment. If not, you may need to add the pre-RFC5378 disclaimer. (See the Legal Provisions document at https://trustee.ietf.org/license-info for more information.) -- The document date (October 26, 2008) is 5660 days in the past. 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Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 SIDR G. Huston 3 Internet-Draft G. Michaelson 4 Intended status: Standards Track R. Loomans 5 Expires: April 29, 2009 APNIC 6 October 26, 2008 8 A Profile for X.509 PKIX Resource Certificates 9 draft-ietf-sidr-res-certs-14 11 Status of this Memo 13 By submitting this Internet-Draft, each author represents that any 14 applicable patent or other IPR claims of which he or she is aware 15 have been or will be disclosed, and any of which he or she becomes 16 aware will be disclosed, in accordance with Section 6 of BCP 79. 18 Internet-Drafts are working documents of the Internet Engineering 19 Task Force (IETF), its areas, and its working groups. Note that 20 other groups may also distribute working documents as Internet- 21 Drafts. 23 Internet-Drafts are draft documents valid for a maximum of six months 24 and may be updated, replaced, or obsoleted by other documents at any 25 time. It is inappropriate to use Internet-Drafts as reference 26 material or to cite them other than as "work in progress." 28 The list of current Internet-Drafts can be accessed at 29 http://www.ietf.org/ietf/1id-abstracts.txt. 31 The list of Internet-Draft Shadow Directories can be accessed at 32 http://www.ietf.org/shadow.html. 34 This Internet-Draft will expire on April 29, 2009. 36 Abstract 38 This document defines a standard profile for X.509 certificates for 39 the purposes of supporting validation of assertions of "right-of-use" 40 of an Internet Number Resource (IP Addresses and Autonomous System 41 Numbers). This profile is used to convey the issuer's authorization 42 of the subject to be regarded as the current holder of a "right-of- 43 use" of the IP addresses and AS numbers that are described in the 44 issued certificate. 46 Table of Contents 48 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4 49 1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 5 50 2. Describing Resources in Certificates . . . . . . . . . . . . . 5 51 3. Resource Certificate Fields . . . . . . . . . . . . . . . . . 6 52 3.1. Version . . . . . . . . . . . . . . . . . . . . . . . . . 6 53 3.2. Serial number . . . . . . . . . . . . . . . . . . . . . . 6 54 3.3. Signature Algorithm . . . . . . . . . . . . . . . . . . . 7 55 3.4. Issuer . . . . . . . . . . . . . . . . . . . . . . . . . . 7 56 3.5. Subject . . . . . . . . . . . . . . . . . . . . . . . . . 7 57 3.6. Valid From . . . . . . . . . . . . . . . . . . . . . . . . 7 58 3.7. Valid To . . . . . . . . . . . . . . . . . . . . . . . . . 8 59 3.8. Subject Public Key Info . . . . . . . . . . . . . . . . . 8 60 3.9. Resource Certificate Version 3 Extension Fields . . . . . 8 61 3.9.1. Basic Constraints . . . . . . . . . . . . . . . . . . 9 62 3.9.2. Subject Key Identifier . . . . . . . . . . . . . . . . 9 63 3.9.3. Authority Key Identifier . . . . . . . . . . . . . . . 9 64 3.9.4. Key Usage . . . . . . . . . . . . . . . . . . . . . . 10 65 3.9.5. CRL Distribution Points . . . . . . . . . . . . . . . 10 66 3.9.6. Authority Information Access . . . . . . . . . . . . . 11 67 3.9.7. Subject Information Access . . . . . . . . . . . . . . 11 68 3.9.8. Certificate Policies . . . . . . . . . . . . . . . . . 13 69 3.9.9. IP Resources . . . . . . . . . . . . . . . . . . . . . 13 70 3.9.10. AS Resources . . . . . . . . . . . . . . . . . . . . . 13 71 4. Resource Certificate Revocation List Profile . . . . . . . . . 14 72 4.1. Version . . . . . . . . . . . . . . . . . . . . . . . . . 14 73 4.2. Issuer Name . . . . . . . . . . . . . . . . . . . . . . . 14 74 4.3. This Update . . . . . . . . . . . . . . . . . . . . . . . 14 75 4.4. Next Update . . . . . . . . . . . . . . . . . . . . . . . 14 76 4.5. Signature . . . . . . . . . . . . . . . . . . . . . . . . 15 77 4.6. Revoked Certificate List . . . . . . . . . . . . . . . . . 15 78 4.6.1. Serial Number . . . . . . . . . . . . . . . . . . . . 15 79 4.6.2. Revocation Date . . . . . . . . . . . . . . . . . . . 15 80 4.7. CRL Extensions . . . . . . . . . . . . . . . . . . . . . . 15 81 4.7.1. Authority Key Identifier . . . . . . . . . . . . . . . 15 82 4.7.2. CRL Number . . . . . . . . . . . . . . . . . . . . . . 16 83 5. Resource Certificate Request Profile . . . . . . . . . . . . . 16 84 5.1. PCKS#10 Profile . . . . . . . . . . . . . . . . . . . . . 16 85 5.1.1. PKCS#10 Resource Certificate Request Template 86 Fields . . . . . . . . . . . . . . . . . . . . . . . . 16 87 5.2. CRMF Profile . . . . . . . . . . . . . . . . . . . . . . . 17 88 5.2.1. CRMF Resource Certificate Request Template Fields . . 18 89 5.2.2. Resource Certificate Request Control Fields . . . . . 19 90 5.3. Certificate Extension Attributes in Certificate 91 Requests . . . . . . . . . . . . . . . . . . . . . . . . . 19 92 6. Resource Certificate Validation . . . . . . . . . . . . . . . 21 93 6.1. Resource Extension Validation . . . . . . . . . . . . . . 22 94 6.2. Resource Certification Path Validation . . . . . . . . . . 23 95 6.3. Trust Anchors for Resource Certificates . . . . . . . . . 24 96 6.3.1. Distribution Format of Default Trust Anchor 97 Material . . . . . . . . . . . . . . . . . . . . . . . 25 98 7. Design Notes . . . . . . . . . . . . . . . . . . . . . . . . . 28 99 8. Security Considerations . . . . . . . . . . . . . . . . . . . 31 100 9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 31 101 10. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 31 102 11. References . . . . . . . . . . . . . . . . . . . . . . . . . . 32 103 11.1. Normative References . . . . . . . . . . . . . . . . . . . 32 104 11.2. Informative References . . . . . . . . . . . . . . . . . . 32 105 Appendix A. Example Resource Certificate . . . . . . . . . . . . 33 106 Appendix B. Example Certificate Revocation List . . . . . . . . . 35 107 Appendix C. Cryptographic Message Syntax Profile for RPKI 108 Trust Anchor Material . . . . . . . . . . . . . . . . 37 109 C.1. Signed-Data ContentType . . . . . . . . . . . . . . . . . 37 110 C.1.1. encapContentInfo . . . . . . . . . . . . . . . . . . . 38 111 C.1.2. signerInfos . . . . . . . . . . . . . . . . . . . . . 39 112 C.2. RTA Validation . . . . . . . . . . . . . . . . . . . . . . 41 113 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 42 114 Intellectual Property and Copyright Statements . . . . . . . . . . 44 116 1. Introduction 118 This document defines a standard profile for X.509 certificates 119 [X.509] for use in the context of certification of IP Addresses and 120 AS Numbers. Such certificates are termed here "Resource 121 Certificates." Resource Certificates are X.509 certificates that 122 conform to the PKIX profile [RFC5280], and also conform to the 123 constraints specified in this profile. Resource Certificates attest 124 that the issuer has granted the subject a "right-of-use" for a listed 125 set of IP addresses and Autonomous System numbers. 127 A Resource Certificate describes an action by a certificate issuer 128 that binds a list of IP Address blocks and AS Numbers to the subject 129 of the issued certificate. The binding is identified by the 130 association of the subject's private key with the subject's public 131 key contained in the Resource Certificate, as signed by the private 132 key of the certificate's issuer. 134 In the context of the public Internet, and the use of public number 135 resources within this context, it is intended that Resource 136 Certificates are used in a manner that is explicitly aligned to the 137 public number resource distribution function. Specifically, when a 138 number resource is allocated or assigned by a number registry to an 139 entity, this allocation is described by an associated Resource 140 Certificate. This certificate is issued by the number registry, and 141 the subject public key that is certified by the issuer corresponds to 142 the public part of a key pair for which the private key is associated 143 with the entity who is the recipient of the number assignment or 144 allocation. A critical extension to the certificate enumerates the 145 IP Resources that were allocated or assigned by the issuer to the 146 entity. In the context of the public number distribution function, 147 this corresponds to a hierarchical PKI structure, where Resource 148 Certificates are issued in only one 'direction' and there is a unique 149 path of certificates from a certification authority operating at the 150 apex of a resource distribution hierarchy to a valid certificate. 152 Validation of a Resource Certificate in such a hierarchical PKI can 153 be undertaken by establishing a valid issuer-subject certificate 154 chain from a certificate issued by a trust anchor certification 155 authority to the certificate [RFC4158], with the additional 156 constraint of ensuring that each subject's listed resources are fully 157 encompassed by those of the issuer at each step in the issuer-subject 158 certificate chain. Validation therefore logically corresponds to 159 validation of an associated set of assignment or allocation actions 160 of IP number resources. 162 While this profile describes the structure of a default Trust Anchor 163 for this PKI, Relying Parties (RPs) in this PKI are free to select 164 the trust anchors upon which they rely, and thus the PKI as viewed by 165 RPs need not match the public resource allocation hierarchy as 166 described here. 168 Resource Certificates may be used in the context of the operation of 169 secure inter-domain routing protocols to convey a right-of-use of an 170 IP number resource that is being passed within the routing protocol, 171 allowing relying parties to verify legitimacy and correctness of 172 routing information. Related use contexts include validation of 173 Internet Routing Registry objects, validation of routing requests, 174 and detection of potential unauthorized use of IP addresses. 176 This profile defines those fields that are used in a Resource 177 Certificate that MUST be present for the certificate to be valid. 178 Relying Parties SHOULD check that a Resource Certificate conforms to 179 this profile as a requisite for validation of a Resource Certificate. 181 1.1. Terminology 183 It is assumed that the reader is familiar with the terms and concepts 184 described in "Internet X.509 Public Key Infrastructure Certificate 185 and Certificate Revocation List (CRL) Profile" [RFC5280], "X.509 186 Extensions for IP Addresses and AS Identifiers" [RFC3779], "Internet 187 Protocol" [RFC0791], "Internet Protocol Version 6 (IPv6) Addressing 188 Architecture" [RFC4291], "Internet Registry IP Allocation Guidelines" 189 [RFC2050], and related regional Internet registry address management 190 policy documents. 192 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 193 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 194 document are to be interpreted as described in RFC 2119. 196 2. Describing Resources in Certificates 198 The framework for describing an association between the subject of a 199 certificate and the resources currently under the subject's control 200 is described in [RFC3779]. 202 There are three aspects of this resource extension that are noted in 203 this profile: 205 1. RFC 3779 notes that a resource extension SHOULD be a CRITICAL 206 extension to the X.509 Certificate. This Resource Certificate 207 profile further specifies that the use of this certificate 208 extension MUST be used in all Resource Certificates and MUST 209 be marked as CRITICAL. 211 2. RFC 3779 defines a sorted canonical form of describing a 212 resource set, with maximal spanning ranges and maximal 213 spanning prefix masks as appropriate. All valid certificates 214 in this profile MUST use this sorted canonical form of 215 resource description in the resource extension field. 217 3. A test of the resource extension in the context of certificate 218 validity includes the condition that the resources described 219 in the immediate parent CA certificate in the PKI (the 220 certificate where this certificate's issuer is the subject) 221 has a resource set (called here the "issuer's resource set") 222 that MUST encompass the resource set of the issued 223 certificate. In this context "encompass" allows for the 224 issuer's resource set to be the same as, or a strict superset 225 of, any subject's resource set. 227 Certificate validation entails the construction of a sequence of 228 valid certificates in an issuer-subject chain (where the subject 229 field of one certificate appears as the issuer in the next 230 certificate in the sequence) from a trust anchor to the certificate 231 being validated. Moreover, the resource extensions in this 232 certificate sequence from the first CA under the trust anchor to the 233 certificate being validated form a sequence of encompassing 234 relationships in terms of the resources described in the resource 235 extension. 237 3. Resource Certificate Fields 239 A Resource Certificate is a valid X.509 v3 public key certificate, 240 consistent with the PKIX profile [RFC5280], containing the fields 241 listed in this section. Unless specifically noted as being OPTIONAL, 242 all the fields listed here MUST be present, and any other field MUST 243 NOT appear in a conforming Resource Certificate. Where a field value 244 is specified here this value MUST be used in conforming Resource 245 Certificates. 247 3.1. Version 249 Resource Certificates are X.509 Version 3 certificates. This field 250 MUST be present, and the Version MUST be 3 (i.e. the value of this 251 field is 2). 253 3.2. Serial number 255 The serial number value is a positive integer that is unique per 256 Issuer. 258 3.3. Signature Algorithm 260 This field describes the algorithm used to compute the signature on 261 this certificate. This profile specifies a default of SHA-256 with 262 RSA (sha256WithRSAEncryption), and allows for the use of SHA-384 or 263 SHA-512. Accordingly, the value for this field MUST be one of the 264 OID values { pkcs-1 11 }, { pkcs-1 12 } or { pkcs-1 13 } [RFC4055]. 266 3.4. Issuer 268 This field identifies the entity that has signed and issued the 269 certificate. The value of this field is a valid X.501 name. 270 Conventions are imposed on Issuer names used in resource 271 certificates, as described in [ID.sidr-arch]. 273 If the certificate is a subordinate certificate issued by virtue of 274 the "cA" bit set in the immediate superior certificate, then the 275 issuer name MUST correspond to the subject name as contained in the 276 immediate superior certificate. 278 3.5. Subject 280 This field identifies the entity to whom the resource has been 281 allocated / assigned. The value of this field is a valid X.501 name. 282 As noted above, conventions are imposed on Subject names used in 283 resource certificates, as described in [ID.sidr-arch]. 285 In this profile the subject name is determined by the issuer, and 286 each distinct subordinate CA and EE certified by the issuer MUST be 287 identified using a subject name that is unique per issuer. 289 In this context "distinct" is defined as an entity and a given public 290 key. An issuer SHOULD use a different subject name if the subject 291 entity or the subject entity's key pair has changed. 293 3.6. Valid From 295 The starting time at which point the certificate is valid. In this 296 profile the "Valid From" time SHOULD be no earlier than the time of 297 certificate generation. As per Section 4.1.2.5 of [RFC5280], 298 Certification Authorities (CAs) conforming to this profile MUST 299 always encode the certificate's "Valid From" date through the year 300 2049 as UTCTime, and dates in 2050 or later MUST be encoded as 301 GeneralizedTime. These two time formats are defined in [RFC5280]. 303 In this profile, it is valid for a certificate to have a value for 304 this field that pre-dates the same field value in any superior 305 certificate. Relying Parties should not attempt to infer from this 306 time information a certificate was valid at a time in the past, or 307 will be valid at a time in the future, as the validity of a 308 certificate refers to validity at the current time. 310 3.7. Valid To 312 The Valid To time is the date and time at which point in time the 313 certificate's validity ends. It represents the anticipated lifetime 314 of the resource allocation / assignment arrangement between the 315 issuer and the subject. As per Section 4.1.2.5 of [RFC5280], CAs 316 conforming to this profile MUST always encode the certificate's 317 "Valid To" date through the year 2049 as UTCTime, and dates in 2050 318 or later MUST be encoded as GeneralizedTime. These two time formats 319 are defined in [RFC5280]. 321 As noted above, it is valid for a certificate to have a value for 322 this field that post-dates the same field value in any superior 323 certificate. The same caveats apply to Relying Party's assumptions 324 relating to the certificate's validity at any time other than the 325 current time, 327 While a CA is typically advised against issuing a certificate with a 328 validity interval that exceeds the validity interval of the CA's 329 certificate that will be used to validate the issued certificate, in 330 the context of this profile, it is anticipated that a CA may have 331 valid grounds to issue a certificate with a validity interval that 332 exceeds the validity interval of its certificate. 334 3.8. Subject Public Key Info 336 This field specifies the subject's public key and the algorithm with 337 which the key is used. The public key algorithm MUST be RSA, and, 338 accordingly, the OID for the public key algorithm is 339 1.2.840.113549.1.1.1. The key size MUST be a minimum size of 2048 340 bits. 342 It is noted that larger key sizes are computationally expensive for 343 both the CA and relying parties, indicating that care should be taken 344 when deciding to use larger than the minimum key size noted above. 346 3.9. Resource Certificate Version 3 Extension Fields 348 As noted in Section 4.2 of [RFC5280], each extension in a certificate 349 is designated as either critical or non-critical. A certificate- 350 using system MUST reject the certificate if it encounters a critical 351 extension it does not recognize; however, a non-critical extension 352 MAY be ignored if it is not recognized [RFC5280]. 354 The following X.509 V3 extensions MUST be present in a conforming 355 Resource Certificate, except where explicitly noted otherwise. 357 3.9.1. Basic Constraints 359 The basic constraints extension identifies whether the subject of the 360 certificate is a CA and the maximum depth of valid certification 361 paths that include this certificate. 363 The issuer determines whether the "cA" boolean is set. If this bit 364 is set, then it indicates that the subject is allowed to issue 365 resources certificates within this overall framework (i.e. the 366 subject is a CA). 368 The Path Length Constraint is not specified in this profile and MUST 369 NOT be present. 371 The Basic Constraints extension field is a critical extension in the 372 Resource Certificate profile, and MUST be present when the subject is 373 a CA, and MUST NOT be present otherwise. 375 3.9.2. Subject Key Identifier 377 The subject key identifier extension provides a means of identifying 378 certificates that contain a particular public key. To facilitate 379 certification path construction, this extension MUST appear in all 380 Resource Certificates. This extension is non-critical. 382 The value of the subject key identifier MUST be the value placed in 383 the key identifier field of the Authority Key Identifier extension of 384 all certificates issued by this subject. 386 The Key Identifier used here is the 160-bit SHA-1 hash of the value 387 of the DER-encoded ASN.1 bit string of the subject public key, as 388 described in Section 4.2.1.2 of [RFC5280]. 390 3.9.3. Authority Key Identifier 392 The authority key identifier extension provides a means of 393 identifying certificates that are signed by the issuer's private key, 394 by providing a hash value of the issuer's public key. To facilitate 395 path construction, this extension MUST appear in all Resource 396 Certificates. The keyIdentifier MUST be present in all Resource 397 Certificates, with the exception of a CA who issues a "self-signed" 398 certificate. The authorityCertIssuer and authorityCertSerialNumber 399 fields MUST NOT be present. This extension is non-critical. 401 The Key Identifier used here is the 160-bit SHA-1 hash of the value 402 of the DER-encoded ASN.1 bit string of the issuer's public key, as 403 described in Section 4.2.1.1 of [RFC5280]. 405 3.9.4. Key Usage 407 This describes the purpose of the certificate. This is a critical 408 extension, and it MUST be present. 410 In certificates issued to Certification Authorities only the 411 keyCertSign and CRLSign bits are set to TRUE and these MUST be the 412 only bits set to TRUE. 414 In end-entity certificates the digitalSignature bit MUST be set to 415 TRUE and MUST be the only bit set to TRUE. 417 3.9.5. CRL Distribution Points 419 This field (CRLDP) identifies the location(s) of the CRL(s) 420 associated with certificates issued by this Issuer. This profile 421 uses the URI form of object identification. The preferred URI access 422 mechanism is a single RSYNC URI ("rsync://") [rsync] that references 423 a single inclusive CRL for each issuer. 425 In this profile the certificate issuer is also the CRL issuer, 426 implying at the CRLIssuer field MUST be omitted, and the 427 distributionPoint field MUST be present. The Reasons field MUST be 428 omitted. 430 The distributionPoint MUST contain general names, and MUST NOT 431 contain a nameRelativeToCRLIssuer. The type of the general name MUST 432 be of type URI. 434 In this profile, the scope of the CRL is specified to be all 435 certificates issued by this CA issuer. 437 The sequence of distributionPoint values MUST contain only a single 438 DistributionPointName set. The DistributionPointName set MAY contain 439 more than one URI value. An RSYNC URI MUST be present in the 440 DistributionPointName set, and reference the most recent instance of 441 this issuer's certificate revocation list. Other access form URIs 442 MAY be used in addition to the RSYNC URI. 444 This extension MUST be present and it is non-critical. There is one 445 exception, namely where a CA distributes its public key in the form 446 of a "self-signed" certificate, the CRLDP MUST be omitted. 448 3.9.6. Authority Information Access 450 This extension (AIA) identifies the point of publication of the 451 certificate that is issued by the issuer's immediate superior CA, 452 where this certificate's issuer is the subject. In this profile a 453 single reference object to publication location of the immediate 454 superior certificate MUST be used, except in the case where a CA 455 distributes its public key in the form of a "self-signed" 456 certificate, in which case the AIA field SHOULD be omitted. 458 This profile uses a URI form of object identification. The preferred 459 URI access mechanisms is "rsync", and an RSYNC URI MUST be specified 460 with an accessMethod value of id-ad-caIssuers. The URI MUST 461 reference the point of publication of the certificate where this 462 issuer is the subject (the issuer's immediate superior certificate). 463 Other access method URIs referencing the same object MAY also be 464 included in the value sequence of this extension. 466 When an Issuer re-issues a CA certificate, the subordinate 467 certificates need to reference this new certificate via the AIA 468 field. In order to avoid the situation where a certificate re- 469 issuance necessarily implies a requirement to re-issue all 470 subordinate certificates, CA Certificate issuers SHOULD use a 471 persistent URL name scheme for issued certificates. This implies 472 that re-issued certificates overwrite previously issued certificates 473 to the same subject in the publication repository, and use the same 474 publication name as previously issued certificates. In this way 475 subordinate certificates can maintain a constant AIA field value and 476 need not be re-issued due solely to a re-issue of the superior 477 certificate. The issuers' policy with respect to the persistence of 478 name objects of issued certificates MUST be specified in the Issuer's 479 Certification Practice Statement. 481 This extension is non-critical. 483 3.9.7. Subject Information Access 485 This extension (SIA) identifies the location of information and 486 services relating to the subject of the certificate in which the SIA 487 extension appears. Where the Subject is a CA in this profile, this 488 information and service collection will include all current valid 489 certificates that have been issued by this subject that are signed 490 with the subject's corresponding private key. 492 This profile uses a URI form of location identification. The 493 preferred URI access mechanism is "rsync", and an RSYNC URI MUST be 494 specified, with an access method value of id-ad-caRepository when the 495 subject of the certificate is a CA. The RSYNC URI MUST reference an 496 object collection rather than an individual object and MUST use a 497 trailing '/' in the URI. 499 Other access method URIs that reference the same location MAY also be 500 included in the value sequence of this extension. The ordering of 501 URIs in this sequence reflect the subject's relative preferences for 502 access methods, with the first method in the sequence being the most 503 preferred. 505 This extension MUST be present when the subject is a CA, and is non- 506 critical. 508 For End Entity (EE) certificates, where the subject is not a CA, this 509 extension MAY be present, and is non-critical. If present, it either 510 references the location where objects signed by the private key 511 associated with the EE certificate can be accessed, or, in the case 512 of single-use EE certificates it references the location of the 513 single object that has been signed by the corresponding private key. 515 When the subject is an End Entity, and it publishes objects signed 516 with the matching private key in a repository, the directory where 517 these signed objects is published is referenced the id-ad- 518 signedObjectRepository OID. 520 id-ad OBJECT IDENTIFIER ::= { id-pkix 48 } 522 id-ad-signedObjectRepository OBJECT IDENTIFIER ::= { id-ad 9 } 524 When the subject is an End Entity, and it publishes a single object 525 signed with the matching private key, the location where this signed 526 object is published is referenced the id-ad-signedObject OID. 528 id-ad-signedObject OBJECT IDENTIFIER ::= { id-ad 11 } 530 This profile requires the use of repository publication manifests 531 [ID.sidr-manifests] to list all signed objects that are deposited in 532 the repository publication point associated with a CA or an EE. The 533 publication point of the manifest for a CA or EE is placed in the SIA 534 extension of the CA or EE certificate. This profile uses a URI form 535 of manifest identification for the accessLocation. The preferred URI 536 access mechanisms is "rsync", and an RSYNC URI MUST be specified. 537 Other accessDescription fields may exist with this id-ad-Manifest 538 accessMethod, where the accessLocation value indicates alternate URI 539 access mechanisms for the same manifest object. 541 id-ad-rpkiManifest OBJECT IDENTIFIER ::= { id-ad 10 } 543 CA certificates MUST include in the SIA an accessMethod OID of id-ad- 544 rpkiManifest, where the associated accessLocation refers to the 545 subject's published manifest object as an object URL. 547 When an EE certificate is intended for use in verifying multiple 548 objects, EE certificate MUST include in the SIA an access method OID 549 of id-ad-rpkiManifest, where the associated access location refers to 550 the publication point of the objects that are verified using this EE 551 certificate. 553 When an EE certificate is used to verify a single published object, 554 the EE certificate MUST include in the SIA an access method OID of 555 id-ad-signedObject, where the associated access location refers to 556 the publication point of the single object that is verified using 557 this EE certificate. In this case, the SIA MUST NOT include the 558 access method OID of id-ad-rpkiManifest. 560 3.9.8. Certificate Policies 562 This extension MUST reference the Resource Certificate Policy, using 563 the OID Policy Identifier value of "1.3.6.1.5.5.7.14.2". This field 564 MUST be present and MUST contain only this value for Resource 565 Certificates. 567 No PolicyQualifiers are defined for use with this policy and thus 568 none must be included in this extension. 570 This extension MUST be present and it is critical. 572 3.9.9. IP Resources 574 This extension contains the list of IP address resources as per 575 [RFC3779]. The value may specify the "inherit" element for a 576 particular AFI value. In the context of resource certificates 577 describing public number resources for use in the public Internet, 578 the SAFI value MUST NOT be used. All Resource Certificates MUST 579 include an IP Resources extension, an AS Resources extension, or both 580 extensions. 582 This extension, if present, MUST be marked critical. 584 3.9.10. AS Resources 586 This extension contains the list of AS number resources as per 587 [RFC3779], or may specify the "inherit" element. RDI values are NOT 588 supported in this profile and MUST NOT be used. All Resource 589 Certificates MUST include an IP Resources extension, an AS Resources 590 extension, or both extensions. 592 This extension, if present, MUST be marked critical. 594 4. Resource Certificate Revocation List Profile 596 Each CA MUST issue a version 2 Certificate Revocation List (CRL), 597 consistent with [RFC5280]. The CRL issuer is the CA, and no indirect 598 CRLs are supported in this profile. 600 An entry MUST NOT be removed from the CRL until it appears on one 601 regularly scheduled CRL issued beyond the revoked certificate's 602 validity period, as required in [RFC5280]. 604 This profile does not allow issuance of Delta CRLs. 606 The scope of the CRL MUST be "all certificates issued by this CA". 607 The contents of the CRL are a list of all non-expired certificates 608 that have been revoked by the CA. 610 No CRL fields other than those listed here are permitted in CRLs 611 issued under this profile. Unless otherwise indicated, these fields 612 MUST be present in the CRL. Where two or more CRLs issued by a 613 single CA with the same scope, the CRL with the highest value of the 614 "CRL Number" field supersedes all other CRLs issued by this CA. 616 4.1. Version 618 Resource Certificate Revocation Lists are Version 2 certificates (the 619 integer value of this field is 1). 621 4.2. Issuer Name 623 The value of this field is the X.501 name of the issuing CA who is 624 also the signer of the CRL, and is identical to the Issuer name in 625 the Resource Certificates that are issued by this issuer. 627 4.3. This Update 629 This field contains the date and time that this CRL was issued. The 630 value of this field MUST be encoded as UTCTime for dates through the 631 year 2049, and MUST be encoded as GeneralizedTime for dates in the 632 year 2050 or later. 634 4.4. Next Update 636 This is the date and time by which the next CRL SHOULD be issued. 637 The value of this field MUST be encoded as UTCTime for dates through 638 the year 2049, and MUST be encoded as GeneralizedTime for dates in 639 the year 2050 or later. 641 4.5. Signature 643 This field contains the algorithm used to sign this CRL. This 644 profile specifies a default of SHA-256 with RSA 645 (sha256WithRSAEncryption), and allows for the use of SHA-384 or SHA- 646 512. 648 It is noted that larger key sizes are computationally expensive for 649 both the CRL Issuer and relying parties, indicating that care should 650 be taken when deciding to use larger than the default key size. 652 4.6. Revoked Certificate List 654 When there are no revoked certificates, then the revoked certificate 655 list MUST be absent. 657 For each revoked resource certificate only the following fields MUST 658 be present. No CRL entry extensions are supported in this profile, 659 and CRL entry extensions MUST NOT be present in a CRL. 661 4.6.1. Serial Number 663 The serial number of the revoked certificate. 665 4.6.2. Revocation Date 667 The time the certificate was revoked. This time MUST NOT be a future 668 date (i.e., a date later than ThisUpdate). The value of this field 669 MUST be encoded as UTCTime for dates through the year 2049, and MUST 670 be encoded as GeneralizedTime for dates in the year 2050 or later. 672 4.7. CRL Extensions 674 The X.509 v2 CRL format allows extensions to be placed in a CRL. The 675 following extensions are supported in this profile, and MUST be 676 present in a CRL. 678 4.7.1. Authority Key Identifier 680 The authority key identifier extension provides a means of 681 identifying the public key corresponding to the private key used to 682 sign a CRL. Conforming CRL issuers MUST use the key identifier 683 method. The syntax for this CRL extension is defined in section 684 4.2.1.1 of [RFC5280]. 686 This extension is non-critical. 688 4.7.2. CRL Number 690 The CRL Number extension conveys a monotonically increasing sequence 691 number of positive integers for a given CA and scope. This extension 692 allows users to easily determine when a particular CRL supersedes 693 another CRL. The highest CRL Number value supersedes all other CRLs 694 issued by the CA with the same scope. 696 This extension is non-critical. 698 5. Resource Certificate Request Profile 700 A resource certificate request MAY use either of PKCS#10 or 701 Certificate Request Message Format (CRMF). A CA Issuer MUST support 702 PKCS#10 and a CA Issuer may, with mutual consent of the subject, 703 support CRMF. 705 5.1. PCKS#10 Profile 707 This profile refines the specification in [RFC2986], as it relates to 708 Resource Certificates. A Certificate Request Message object, 709 formatted according to PKCS#10, is passed to a CA as the initial step 710 in issuing a certificate. 712 This request may be conveyed to the CA via a Registration Authority 713 (RA), acting under the direction of a Subject. 715 With the exception of the public key related fields, the CA is 716 permitted to alter any requested field when issuing a corresponding 717 certificate. 719 5.1.1. PKCS#10 Resource Certificate Request Template Fields 721 This profile applies the following additional constraints to fields 722 that may appear in a CertificationRequestInfo: 724 Version 725 This field is mandatory and MUST have the value 0. 727 Subject 728 This field is optional. If present, the value of this field 729 SHOULD be empty, in which case the issuer MUST generate a 730 subject name that is unique in the context of certificates 731 issued by this issuer. If the value of this field is non- 732 empty, then the CA MAY consider the value of this field as the 733 subject's suggested subject name, but the CA is NOT bound to 734 honor this suggestion, as the subject name MUST be unique per 735 subordinate CA and EE in certificates issued by this issuer. 737 SubjectPublicKeyInfo 738 This field specifies the subject's public key and the algorithm 739 with which the key is used. The public key algorithm MUST be 740 RSA, and the OID for the algorithm is 1.2.840.113549.1.1.1. 741 This field also includes a bit-string representation of the 742 entity's public key. For the RSA public-key algorithm the bit 743 string contains the DER encoding of a value of PKCS #1 type 744 RSAPublicKey. 746 Attributes 747 [RFC2986] defines the attributes field as key-value pairs where 748 the key is an OID and the value's structure depends on the key. 750 The only attribute used in this profile is the ExtensionRequest 751 attribute as defined in [RFC2985]. This attribute contains 752 X509v3 Certificate Extensions. The profile for extensions in 753 certificate requests is specified in Section 5.3. 755 This profile applies the following additional constraints to fields 756 that MAY appear in a CertificationRequest Object: 758 signatureAlgorithm 759 This profile specifies a default of SHA-256 with RSA 760 (sha256WithRSAEncryption), and allows for the use of SHA-384 or 761 SHA-512. Accordingly, the value for this field MUST be one of 762 the OID values { pkcs-1 11 }, { pkcs-1 12 } or { pkcs-1 13 } 763 [RFC4055]. 765 It is noted that larger key sizes are computationally expensive 766 for both the CA and relying parties, indicating that care 767 should be taken when deciding to use larger than the default 768 key size. 770 5.2. CRMF Profile 772 This profile refines the Certificate Request Message Format (CRMF) 773 specification in [RFC4211], as it relates to Resource Certificates. 774 A Certificate Request Message object, formatted according to the 775 CRMF, is passed to a CA as the initial step in issuing a certificate. 777 This request MAY be conveyed to the CA via a Registration Authority 778 (RA), acting under the direction of a subject. 780 With the exception of the public key related fields, the CA is 781 permitted to alter any requested field when issuing a corresponding 782 certificate. 784 5.2.1. CRMF Resource Certificate Request Template Fields 786 This profile applies the following additional constraints to fields 787 that may appear in a Certificate Request Template: 789 Version 790 This field MAY be absent, or MAY specify the request of a 791 Version 3 Certificate. It SHOULD be omitted. 793 SerialNumber 794 As per [RFC4211], this field is assigned by the CA and MUST be 795 omitted in this profile. 797 SigningAlgorithm 798 As per [RFC4211], this field is assigned by the CA and MUST be 799 omitted in this profile. 801 Issuer 802 This field is assigned by the CA and MUST be omitted in this 803 profile. 805 Validity 806 This field MAY be omitted. If omitted, the CA will issue a 807 Certificate with Validity dates as determined by the CA. If 808 specified, then the CA MAY override the requested values with 809 dates as determined by the CA. 811 Subject 812 This field is optional. If present, the value of this field 813 SHOULD be empty, in which case the issuer MUST generate a 814 subject name that is unique in the context of certificates 815 issued by this issuer. If the value of this field is non- 816 empty, then the CA MAY consider the value of this field as the 817 subject's suggested subject name, but the CA is NOT bound to 818 honor this suggestion, as the subject name MUST be unique per 819 issuer in certificates issued by this issuer. 821 PublicKey 822 This field MUST be present. 824 extensions 825 This attribute contains X509v3 Certificate Extensions. The 826 profile for extensions in certificate requests is specified in 827 Section 5.3. 829 5.2.2. Resource Certificate Request Control Fields 831 The following control fields are supported in this profile: 833 Authenticator Control 834 It is noted that the intended model of authentication of the 835 subject is a long term one, and the advice as offered in 836 [RFC4211] is that the Authenticator Control field be used. 838 5.3. Certificate Extension Attributes in Certificate Requests 840 The following extensions MAY appear in a PKCS#10 or CRMF Certificate 841 Request. Any other extensions MUST NOT appear in a Certificate 842 Request. This profile places the following additional constraints on 843 these extensions.: 845 BasicConstraints 846 If this is omitted then the CA will issue an end entity 847 certificate with the BasicConstraints extension not present in 848 the issued certificate. 850 The Path Length Constraint is not supported in this Resource 851 Certificate Profile, and this field MUST be omitted in this 852 profile. 854 The CA MAY honor the SubjectType CA bit set to on. If this bit 855 is set, then it indicates that the Subject is allowed to issue 856 resource certificates within this overall framework. 858 The CA MUST honor the SubjectType CA bit set to off (End Entity 859 certificate request), in which case the corresponding end 860 entity certificate will not contain a BasicConstraints 861 extension. 863 SubjectKeyIdentifier 864 This field is assigned by the CA and MUST be omitted in this 865 profile. 867 AuthorityKeyIdentifier 868 This field is assigned by the CA and MUST be omitted in this 869 profile. 871 KeyUsage 872 The CA MAY honor KeyUsage extensions of keyCertSign and cRLSign 873 if present, as long as this is consistent with the 874 BasicConstraints SubjectType sub field, when specified. 876 SubjectInformationAccess 877 This field MUST be present when the subject is a CA, and the 878 field value SHOULD be honored by the CA. If the CA is not able 879 to honor the requested field value, then the CA MUST reject the 880 Certificate Request. 882 This field (SIA) identifies the location of information and 883 services relating to the subject of the certificate in which 884 the SIA extension appears. 886 Where the subject is a CA in this profile, this information and 887 service collection will include all current valid certificates 888 that have been issued by this subject that are signed with the 889 subject's corresponding private key. 891 This profile uses a URI form of location identification. An 892 RSYNC URI MUST be specified, with an access method value of id- 893 ad-caRepository when the subject of the certificate is a CA. 894 The RSYNC URI MUST reference an object collection rather than 895 an individual object and MUST use a trailing '/' in the URI. 896 Other access method URIs that reference the same location MAY 897 also be included in the value sequence of this extension. The 898 ordering of URIs in this sequence reflect the subject's 899 relative preferences for access methods, with the first method 900 in the sequence being the most preferred by the Subject. 902 A request for a CA certificate MUST include in the SIA of the 903 request the id-ad-caRepository access method, and also MUST 904 include in the SIA of the request the accessMethod OID of id- 905 ad-rpkiManifest, where the associated accessLocation refers to 906 the subject's published manifest object as an object URL. 908 This field MAY be present when the subject is a EE. If it is 909 present the field value SHOULD be honored by the CA. If the CA 910 is not able to honor the requested field value, then the CA 911 MUST reject the Certificate Request. If it is not present the 912 CA SHOULD honor this request and omit the SIA from the issued 913 certificate. If the CA is not able to honor the request to 914 omit the SIA, then the CA MUST reject the Certificate Request. 916 When an EE certificate is intended for use in verifying 917 multiple objects, the certificate request for the EE 918 certificate MUST include in the SIA of the request an access 919 method OID of id-ad-signedObjectRepository, and also MUST 920 include in the SIA of the request an access method OID of id- 921 ad-rpkiManifest, where the associated access location refers to 922 the publication point of the objects that are verified using 923 this EE certificate. 925 When an EE certificate is used to sign a single published 926 object, the certificate request for the EE certificate MUST 927 include in the SIA of the request an access method OID of id- 928 ad-signedObject, where the associated access location refers to 929 the publication point of the single object that is verified 930 using this EE certificate, and MUST NOT include an id-ad- 931 rpkiManifest access method OID in the SIA of the request. 933 In the case when the EE certificate is to be used exclusively 934 to sign one or more unpublished objects, such that the all 935 signed objects will not be published in any RPKI repository, 936 then the SIA SHOULD be omitted from the request. 938 CRLDistributionPoints 939 This field is assigned by the CA and MUST be omitted in this 940 profile. 942 AuthorityInformationAccess 943 This field is assigned by the CA and MUST be omitted in this 944 profile. 946 CertificatePolicies 947 This field is assigned by the CA and MUST be omitted in this 948 profile. 950 With the exceptions of the publicKey field and the 951 SubjectInformationAccess field, the CA is permitted to alter any 952 requested field. 954 6. Resource Certificate Validation 956 This section describes the Resource Certificate validation procedure. 957 This refines the generic procedure described in section 6 of 958 [RFC5280]. 960 To meet this goal, the path validation process verifies, among other 961 things, that a prospective certification path (a sequence of n 962 certificates) satisfies the following conditions: 964 1. for all x in {1, ..., n-1}, the subject of certificate x is 965 the issuer of certificate x+1; 967 2. certificate 1 is issued by a trust anchor (Note that a trust 968 anchor is NOT a resource certificate in this context and thus 969 does not contain RFC 3779 extensions.); 971 3. certificate n is the certificate to be validated; and 973 4. for all x in {1, ..., n}, the certificate is valid. 975 6.1. Resource Extension Validation 977 The IP resource extension definition [RFC3779] defines a critical 978 extensions for Internet number resources. These are ASN.1 encoded 979 representations of the IPv4 and IPv6 address range (either as a 980 prefix/length, or start-end pair) and the AS number set. 982 Valid Resource Certificates MUST have a valid IP address and/or AS 983 number resource extension. In order to validate a Resource 984 Certificate the resource extension MUST also be validated. This 985 validation process relies on definitions of comparison of resource 986 sets: 988 more specific 989 Given two IP address or AS number contiguous ranges, A and B, A 990 is "more specific" than B if range B includes all IP addresses 991 or AS numbers described by range A, and if range B is larger 992 than range A. 994 equal 995 Given two IP address or AS number contiguous ranges, A and B, A 996 is "equal" to B if range A describes precisely the same 997 collection of IP addresses or AS numbers as described by range 998 B. The definition of "inheritance" in [RFC3779] is equivalent 999 to this "equality" comparison. 1001 encompass 1002 Given two IP address and AS number sets X and Y, X 1003 "encompasses" Y if, for every contiguous range of IP addresses 1004 or AS numbers elements in set Y, the range element is either 1005 more specific than or equal to a contiguous range element 1006 within the set X. 1008 Validation of a certificate's resource extension in the context of an 1009 ordered certificate sequence of {1,2, ... , n} where '1' is issued by 1010 a trust anchor and 'n' is the target certificate, and where the 1011 subject of certificate 'x' is the issuer of certificate 'x' + 1, 1012 implies that the resources described in certificate 'x' "encompass" 1013 the resources described in certificate 'x' + 1, and the resources 1014 described in the trust anchor information "encompass" the resources 1015 described in certificate 1. 1017 6.2. Resource Certification Path Validation 1019 Validation of signed resource data using a target resource 1020 certificate consists of assembling an ordered sequence (or 1021 'Certification Path') of certificates ({1,2,...n} where '1' is a 1022 certificate that has been issued by a trust anchor, and 'n' is the 1023 target certificate) verifying that all of the following conditions 1024 hold: 1026 1. The certificate can be verified using the Issuer's public key 1027 and the signature algorithm 1029 2. The current time lies within the certificate's Validity From 1030 and To values. 1032 3. The certificate contains all fields that MUST be present and 1033 contains field values as specified in this profile for all 1034 field values that MUST be present. 1036 4. No field value that MUST NOT be present in this profile is 1037 present in the certificate. 1039 5. The Issuer has not revoked the certificate by placing the 1040 certificate's serial number on the Issuer's current 1041 Certificate Revocation List, and the Certificate Revocation 1042 List is itself valid. 1044 6. That the resource extension data is "encompassed" by the 1045 resource extension data contained in a valid certificate where 1046 this Issuer is the Subject (the previous certificate in the 1047 ordered sequence) 1049 7. The Certification Path originates with a certificate issued by 1050 a trust anchor, and there exists a signing chain across the 1051 Certification Path where the Subject of Certificate x in the 1052 Certification Path matches the Issuer in Certificate x+1 in 1053 the Certification Path. 1055 A certificate validation algorithm may perform these tests in any 1056 chosen order. 1058 Certificates and CRLs used in this process may be found in a locally 1059 maintained cache, maintained by a regular synchronization across the 1060 distributed publication repository structure. 1062 There exists the possibility of encountering certificate paths that 1063 are arbitrarily long, or attempting to generate paths with loops as 1064 means of creating a potential DOS attack on a relying party. Some 1065 further heuristics may be required to halt the certification path 1066 validation process in order to avoid some of the issues associated 1067 with attempts to validate such structures. It is suggested that 1068 implementations of Resource Certificate validation MAY halt with a 1069 validation failure if the certification path length exceeds a pre- 1070 determined configuration parameter. 1072 6.3. Trust Anchors for Resource Certificates 1074 The default trust model for the resource certificate PKI maps to the 1075 extant public resource allocation system, comprised of IANA, RIRs, 1076 NIRs (in some regions) and LIRs. This is a strict hierarchy, in that 1077 any number resource and a corresponding recipient entity has only one 1078 'parent' issuing registry for that resource. Moreover, the issuing 1079 registry is not a direct or indirect subordinate recipient entity of 1080 the recipient entity in question (i.e., there are no loops in the 1081 model). 1083 Nonetheless, as in any PKI, selection of one or more entities as 1084 trust anchor is a task undertaken by each relying party. The 1085 structure of the resource certificate profile admits the same variety 1086 of trust models as PKIX (and X.509) standards. There is only one 1087 additional caveat on the general applicability of trust models, 1088 namely that in forming a validation path to a CA immediately below a 1089 trust anchor, the sequence of certificates MUST preserve the resource 1090 extension validation property, as described in Section 6.1. 1091 Section 6.1. 1093 The trust anchor information, describing a CA that serves as a trust 1094 anchor, includes the following: 1096 1. the trust anchor name, 1098 2. the public key algorithm, 1099 3. the trust anchor's public key, and 1101 4. optionally, parameters associated with the public key. 1103 The trust anchor information may be provided to the path processing 1104 procedure in the form of a self-signed certificate. 1106 6.3.1. Distribution Format of Default Trust Anchor Material 1108 In the RPKI, the certificate framework corresponds to the hierarchies 1109 of the resource distribution function. In consideration of this, it 1110 is reasonable to nominate to relying parties a default set of trust 1111 anchors for the RPKI that correspond to the entities who operate at 1112 the upper levels of the associated resource allocation hierarchy. 1113 The corresponding nominated trust anchor CA(s) should therefore map, 1114 in some fashion, to apex point(s) of the hierarchical resource 1115 distribution structure. 1117 The characteristics of a trust anchor framework for the RPKI includes 1118 the following considerations: 1120 * The entity or entities that issue proposed trust anchor 1121 material for the RPKI should be as close as possible to the 1122 apex of the associated resource distribution hierarchy. 1124 * Such trust anchor material SHOULD be long-lived. As it can be 1125 reasonably anticipated that default trust anchor material would 1126 be distributed with relying party validation software, the 1127 implication is that the distributed default trust anchor 1128 material SHOULD remain constant for extended time intervals. 1130 * It is a poor trust model when any entity that issues putative 1131 trust anchor material claims to be authoritative for 1132 information or actions of which the entity has no direct 1133 knowledge, nor is in possession of a current definitive record 1134 of such actions. Entities who propose themselves in a role of 1135 a trust anchor issuer SHOULD be able to point to corroborative 1136 material supporting the assertion that they are legitimate 1137 authorities for the information for which they are representing 1138 themselves as a trust anchor for relying parties. 1140 An entity offering itself as a putative trust anchor for a part of 1141 the RPKI is required to regularly publish an RPKI CA certificate at a 1142 stable URL, and to publish this URL as distributed trust anchor 1143 material, as follows: 1145 * The entity issues an RPKI self-signed "root" CA certificate 1146 that is used as the apex of an RPKI certificate validation 1147 tree. This certificate MUST meet all of the criteria 1148 established in Section 3 of this document for a self-signed 1149 RPKI certificate. This certificate MUST be reissued 1150 periodically, prior to its expiration, and MUST be reissued 1151 upon any change in the resource set that has been allocated to 1152 the entity operating this CA. The validity interval of this 1153 certificate SHOULD reflect the anticipated period of changes to 1154 the entity's resource set . 1156 * The entity maintains a trust anchor key pair that is distinct 1157 from the key pair represented in the self-signed RPKI CA noted 1158 above. 1160 * The entity issues a self-signed CA certificate [RFC5280] (that 1161 contains no RFC 3779 extension) where the subject public key in 1162 the certificate is the public key of the trust anchor and the 1163 certificate is signed using the corresponding private key of 1164 trust anchor key pair. This is called the TA CA certificate. 1165 This certificate MUST have the keyCertSign sign bit set in the 1166 key usage extension, and the CA flag set in the basic 1167 constraints extension, no AIA value and no CRLDP value. The 1168 validity period of this certificate should be very long, as is 1169 the norm for trust anchor material. The SIA of this 1170 certificate references a publication point where the CRL and 1171 the CMS structure defined below are published. 1173 * The trust anchor (TA) issues an EE certificate (a TA EE 1174 certificate) with a validity period identical to the validity 1175 period of its RPKI self-signed "root" CA certificate. This EE 1176 certificate MUST have the digitalSignature bit set, and this 1177 MUST be the only bit set to TRUE. There is no BasicConstraints 1178 extension in this certificate. The validity period of this TA 1179 EE certificate SHOULD be aligned to the validity period of the 1180 RPKI self-signed "root" CA certificate. 1182 * The TA CA regularly issues a CRL. The CRL issuance cycle 1183 SHOULD be shorter than the validity period for the RPKI self- 1184 signed "root" certificate. 1186 * Each time the RPKI self-signed "root" certificate is re-issued, 1187 or prior to the expiration of the TA EE certificate, the TA 1188 generates a Cryptographic Message Syntax (CMS) [RFC3852] 1189 signed-data object, the payload of which is an RPKI self-signed 1190 "root" certificate. The object is CMS-signed with the private 1191 key of the TA EE certificate. The TA EE certificate is 1192 included as a CMS signed attribute in the CMS object. The TA 1193 CA certificate and the associated CRL are not to be included in 1194 the CMS object. The format of the CMS object is specified in 1195 Appendix C. The CMS object is published at the location 1196 referenced in the SIA of the TA CA certificate. 1198 * The entity publicly distributes the TA CA certificate as its 1199 trust anchor material, in an out-of-band fashion, e.g., as part 1200 of widely distributed relying party software. 1202 Relying Parties can assemble the default trust anchor collection by 1203 using the TA CA certificate for each nominated trust anchor: 1205 * The TA CA's CRL and CMS objects can be retrieved from the 1206 publication point referenced by the SIA in the TA CA 1207 certificate. 1209 * The CRL can be verified against the TA CA certificate. 1211 * The CMS signature can be verified using the included TA EE 1212 certificate together with the retrieved CRL and the self-signed 1213 TA CA certificate. 1215 * The relying party can then load the enclosed RPKI self-signed 1216 CA certificate as a trust anchor for RPKI validation for those 1217 resources described in the IP Resource extensions [RFC3779] of 1218 this RPKI certificate. 1220 Relying Parties SHOULD perform this retrieval and validation 1221 operation at intervals no less frequent than the nextUpdate time of 1222 the published TA CA CRL, and SHOULD perform the retrieval operation 1223 prior to the expiration of the TA EE certificate, or upon revocation 1224 of the TA EE certificate that is used to verify the CMS object that 1225 holds the trust anchor's current RPKI self-signed CA certificate. 1227 If a trust anchor chooses to reissue its RPKI self- signed CA 1228 certificate before the expiration of that certificate, it MUST 1229 perform the follow actions: revise the nextUpdate time of the TA CA's 1230 CRL to reflect the issue date for the new TA EE certificate, issue a 1231 new TA EE certificate and a new CMS object with the new RPKI self- 1232 signed CA certificate, and revoke the old TA EE certificate at the 1233 nextUpdate time in the next issued CRL. This revocation will provide 1234 an indication to relying parties to perform the retrieval operation 1235 of the RPKI self-signed CA certificate at a time earlier than the 1236 normal update cycle time. . 1238 7. Design Notes 1240 The following notes provide some additional commentary on the 1241 considerations that lie behind some of the design choices that were 1242 made in the design of this certificate profile. These notes do not 1243 constitute a formal part of the profile specification, and the 1244 interpretation of key words as defined in RFC2119 are not applicable 1245 in this section of the document. 1247 Certificate Extensions: 1248 This profile does not permit the use of any other critical or 1249 non-critical extensions. The rationale for this restriction is 1250 that the resource certificate profile is intended for a 1251 specific use, and in this context it is not seen as being 1252 appropriate to be in the position of having certificates with 1253 additional non-critical extensions that relying parties may see 1254 as valid certificates without understanding the extensions, but 1255 were the relying party in a position to understand the 1256 extensions, would contradict or qualify in some way this 1257 original judgment of validity. This profile takes the position 1258 of minimalism over extensibility. The specific goal for the 1259 associated Resource Public Key Infrastructure to precisely 1260 match the IP number resource allocation structure through an 1261 aligned certificate structure that describes the allocation and 1262 its context within the number resource distribution hierarchy. 1263 The profile defines a resource certificate that is structured 1264 to meet these requirements. 1266 Certification Authorities and Key Values: 1267 This profile uses a definition of an instance of a CA as a 1268 combination of a named entity and a key pair. Within this 1269 definition a CA instance cannot rollover a key pair. However, 1270 the entity can generate a new instance of a CA with a new key 1271 pair and roll over all the signed subordinate products to the 1272 new CA. 1274 This has a number of implications in terms of subject name 1275 management, CRL Scope and repository publication point 1276 management. 1278 Subject Name: 1279 For Subject Names the issuer should ensure that when an 1280 entity requests a certificate with a new key pair, the CA 1281 issues a certificate with a new subject name. One way to 1282 achieve this is for the issuer to use a mapping of the 1283 hash of the subject public key value into a character 1284 string for a CommonName that becomes the CA Subject Name. 1286 CRL Scope: 1287 For CRL Scope this profile specifies that a CA issues a 1288 single CRL sequence, and the scope of the CRL is all 1289 certificates issued by this CA. Because the CA instance 1290 is bound to a single key pair this implies that the CA's 1291 public key, the key used to validate the CA's CRL, and 1292 the key used to validate the certificates revoked by that 1293 CRL are all the same. 1295 Repository Publication Point: 1296 The definition of a CA affects the design of the 1297 repository publication system. In order to minimize the 1298 amount of forced re-certification on key rollover events, 1299 a repository publication regime that uses the same 1300 repository publication point for all CA instances that 1301 refers to the same entity, but with different key values 1302 will minimize the extent of re-generation of certificates 1303 to only immediate subordinate certificates. 1305 In order for two or more CA instances to share a single 1306 repository publication point there needs to be a regime 1307 of key management into OLD, CURRENT and FUTURE keys and a 1308 similar regime of OLD, CURRENT and FUTURE CAs. An OLD CA 1309 should regularly publish its CRL for as long as the OLD 1310 CA instance is still valid, and issue EE certificates as 1311 necessary to maintain a current manifest of all OLD CA 1312 published products, but it should not sign any other 1313 products. The CURRENT CA should publish its CRL, and 1314 should publish all subordinate products, as well as 1315 issuing EE certificates as necessary to maintain a 1316 current manifest of all CURRENT CA published products. 1317 FUTURE CAs should publish no products at all in the 1318 repository publication point. It would be consistent 1319 with this repository object name framework for the CRL 1320 and manifest to be published using object names derived 1321 from the hash of the public key value of the CA instance. 1323 Key Rollover: 1324 As a CA instance is associated with a single key pair, there 1325 are some considerations regarding the procedure that should be 1326 followed by an entity performing a key rollover function. The 1327 entity will need to create a new CA instance and then use this 1328 new CA instance to re-issue all subordinate products with the 1329 new CA instance. 1331 To perform a key rollover operation the entity will need to: 1333 1. Generate a NEW key pair. 1335 2. Generate a certificate request with the NEW key 1336 pair and pass the request to the entity's issuer. 1338 3. Request the entity's issuer to generate and publish 1339 a NEW CA certificate, with an issuer-selected 1340 subject name that is distinct from the subject name 1341 used in conjunction with the previous subject name 1342 value for this entity. 1344 4. Mark the CURRENT CA as OLD and the NEW CA as 1345 CURRENT. 1347 5. The CURRENT CA will generate new certificates for 1348 all existing subordinate CA and EE certificates, 1349 and publish those products in the same repository 1350 publication point and with the same repository 1351 publication point name as the previous OLD 1352 subordinate CA and EE certificates. The keys in 1353 these reissued certificates MUST not change. 1355 6. Where the signing structure uses a packaging format 1356 that includes the EE certificate within the signed 1357 data, signed objects that included OLD EE 1358 certificates in their signed data will need to be 1359 re-signed using an EE certificate issued by the 1360 CURRENT CA. In the case where the OLD EE 1361 certificate is a "single use" EE certificate and 1362 the associate private key has been destroyed this 1363 will entail the generate of a new key pair, the 1364 issuing of an EE certificate by the CURRENT CA. In 1365 the case of a "multi-use" EE certificate, the EE 1366 certificate should issued using the CURRENT CA. 1367 The object, together with the issued EE 1368 certificate, should be signed with the associated 1369 private key, and published in the same repository 1370 publication point, using the same repository 1371 publication point name, as the previously signed 1372 object that it replaces (i.e. overwrite the old 1373 signed object). 1375 7. Generate a certificate revocation request for the 1376 OLD CA certificate and pass it to the entity's 1377 issuer. 1379 8. Remove all published OLD CA products and destroy 1380 the OLD private key. 1382 Name Uniqueness: 1383 This profile specifies that subject names must be unique per 1384 issuer, and does not specify that subject names must be 1385 globally unique. 1387 Given that the Resource Certificate PKI is a distributed PKI, 1388 there is no inherent ability for Certification authorities to 1389 coordinate PKI-wide unique subject names. IANA and the RIRs 1390 SHOULD use multi-attribute, structured Subject names in their 1391 RPKI certificates. All other entities (NIRs, LIRs, etc.) MUST 1392 be issued certificates in which the Subject name contains a 1393 single relative distinguished name, consisting of a CommonName 1394 attribute. This restriction is motivated by the need to change 1395 the names of these CAs when key rollover occurs, and to 1396 minimize liability for issuers in the RPKI. Also, as the 1397 publication repository is distributed, and distinct entities 1398 use distinct repository publication points any potential 1399 ambiguity is resolved by the distinct publication point. 1401 8. Security Considerations 1403 The Security Considerations of [RFC5280] and [RFC3779]apply to 1404 Resource Certificates as defined by this profile, and their use. 1406 A Resource Certificate PKI cannot in and of itself resolve any forms 1407 of ambiguity relating to uniqueness of assertions of rights of use in 1408 the event that two or more valid certificates encompass the same 1409 resource. If the issuance of resource certificates is aligned to the 1410 status of resource allocations and assignments then the information 1411 conveyed in a certificate is no better than the information in the 1412 allocation and assignment databases. 1414 9. IANA Considerations 1416 [Note to IANA, to be removed prior to publication: there are no IANA 1417 considerations stated in this document.] 1419 10. Acknowledgements 1421 The authors would like to acknowledge the valued contributions from 1422 Stephen Kent, Robert Kisteleki, Randy Bush, Russ Housley, Ricardo 1423 Patara and Rob Austein in the preparation and subsequent review of 1424 this document. The document also reflects review comments received 1425 from Sean Turner and David Cooper. 1427 11. References 1429 11.1. Normative References 1431 [RFC0791] Postel, J., "Internet Protocol", STD 5, RFC 791, 1432 September 1981. 1434 [RFC2050] Hubbard, K., Kosters, M., Conrad, D., Karrenberg, D., and 1435 J. Postel, "INTERNET REGISTRY IP ALLOCATION GUIDELINES", 1436 BCP 12, RFC 2050, November 1996. 1438 [RFC3779] Lynn, C., Kent, S., and K. Seo, "X.509 Extensions for IP 1439 Addresses and AS Identifiers", RFC 3779, June 2004. 1441 [RFC3852] Housley, R., "Cryptographic Message Syntax (CMS)", 1442 RFC 3852, July 2004. 1444 [RFC4055] Schaad, J., Kaliski, B., and R. Housley, "Additional 1445 Algorithms and Identifiers for RSA Cryptography for use in 1446 the Internet X.509 Public Key Infrastructure Certificate 1447 and Certificate Revocation List (CRL) Profile", RFC 4055, 1448 June 2005. 1450 [RFC4211] Schaad, J., "Internet X.509 Public Key Infrastructure 1451 Certificate Request Message Format (CRMF)", RFC 4211, 1452 September 2005. 1454 [RFC4291] Hinden, R. and S. Deering, "IP Version 6 Addressing 1455 Architecture", RFC 4291, February 2006. 1457 [RFC5280] Cooper, D., Santesson, S., Farrell, S., Boeyen, S., 1458 Housley, R., and W. Polk, "Internet X.509 Public Key 1459 Infrastructure Certificate and Certificate Revocation List 1460 (CRL) Profile", RFC 5280, May 2008. 1462 [X.509] ITU-T, "Recommendation X.509: The Directory - 1463 Authentication Framework", 2000. 1465 11.2. Informative References 1467 [ID.sidr-arch] 1468 Lepinski, M. and S. Kent, "An Infrastructure to Support 1469 Secure Internet Routing", Work in progress: Internet 1470 Drafts draft-ietf-sidr-arch-03.txt, February 2008. 1472 [ID.sidr-manifests] 1473 Austein, R., Huston, G., Kent, S., and M. Lepinski, 1474 "Manifests for the Resource Public Key Infrastructure", 1475 Work in progress: Internet 1476 Drafts draft-ietf-sidr-rpki-manifests-00.txt, 1477 January 2008. 1479 [RFC2985] Nystrom, M. and B. Kaliski, "PKCS #9: Selected Object 1480 Classes and Attribute Types Version 2.0", RFC 2985, 1481 November 2000. 1483 [RFC2986] Nystrom, M. and B. Kaliski, "PKCS #10: Certification 1484 Request Syntax Specification Version 1.7", RFC 2986, 1485 November 2000. 1487 [RFC4158] Cooper, M., Dzambasow, Y., Hesse, P., Joseph, S., and R. 1488 Nicholas, "Internet X.509 Public Key Infrastructure: 1489 Certification Path Building", RFC 4158, September 2005. 1491 [rsync] Tridgell, A., "rsync", April 2006, 1492 . 1494 Appendix A. Example Resource Certificate 1496 The following is an example Resource Certificate. 1498 Certificate Name: hu9fdDBq60mrk7cPRuX2DYuXSRQ-3.cer 1500 Data: 1501 Version: 3 1502 Serial: 3 1503 Signature Algorithm: Hash: SHA256, Encryption: RSA 1504 Issuer: CN=Demo Production APNIC CA - Not for real use, 1505 E=ca@apnic.net 1506 Validity: 1507 Not Before: Thu Jul 27 06:34:04 2006 GMT 1508 Not After: Fri Jul 27 06:34:04 2007 GMT 1509 Subject: CN=APNIC own-use network resources 1510 Subject Key Identifier: 1511 86:ef:5f:74:30:6a:eb:49:ab:93:b7:0f:46:e5:f6:0d: 1512 8b:97:49:14 1513 Subject Key Identifier g(SKI): 1514 hu9fdDBq60mrk7cPRuX2DYuXSRQ 1515 Subject Public Key Info: 1516 Public Key Algorithm: rsaEncryption 1517 RSA Public Key: Modulus: 1518 c1:25:a1:b0:db:89:83:a0:fc:f1:c0:e4:7b:93:76:c1: 1519 59:b7:0d:ac:25:25:ed:88:ce:00:03:ea:99:1a:9a:2a: 1520 0e:10:2e:5f:c0:45:87:47:81:7b:1d:4d:44:aa:65:a3: 1521 f8:07:84:32:ea:04:70:27:05:2b:79:26:e6:e6:3a:cb: 1522 b2:9a:65:6c:c1:4e:d7:35:fb:f6:41:1e:8b:1c:b8:e4: 1523 5a:3a:d6:d0:7b:82:9a:23:03:f8:05:4c:68:42:67:fe: 1524 e7:45:d9:2c:a6:d1:b3:da:cf:ad:77:c5:80:d2:e3:1e: 1525 4d:e8:bf:a2:f2:44:10:b2:2f:61:bc:f4:89:31:54:7c: 1526 56:47:d5:b1:c3:48:26:95:93:c9:6f:70:14:4d:ac:a5: 1527 c2:8e:3d:1f:6d:f8:d4:93:9d:14:c7:15:c7:34:8e:ba: 1528 dd:70:b3:c2:2b:08:78:59:97:dd:e4:34:c7:d8:de:5c: 1529 f7:94:6f:95:59:ba:29:65:f5:98:15:8f:8e:57:59:5d: 1530 92:1f:64:2f:b5:3d:69:2e:69:83:c2:10:c6:aa:8e:03: 1531 d5:69:11:bd:0d:b5:d8:27:6c:74:2f:60:47:dd:2e:87: 1532 24:c2:36:68:2b:3c:fd:bd:22:57:a9:4d:e8:86:3c:27: 1533 03:ce:f0:03:2e:59:ce:05:a7:41:3f:2f:64:50:dd:e7 1534 RSA Public Key: Exponent: 65537 1535 Basic Constraints: CA: TRUE 1536 Subject Info Access: 1537 caRepository - rsync://repository.apnic.net/APNIC/ 1538 pvpjvwUeQix2e54X8fGbhmdYMo0/ 1539 q66IrWSGuBE7jqx8PAUHAlHCqRw/ 1540 hu9fdDBq60mrk7cPRuX2DYuXSRQ/ 1541 Key Usage: keyCertSign, cRLSign 1542 CRL Distribution Points: 1543 rsync://repository.apnic.net/APNIC/ 1544 pvpjvwUeQix2e54X8fGbhmdYMo0/ 1545 q66IrWSGuBE7jqx8PAUHAlHCqRw/ 1546 q66IrWSGuBE7jqx8PAUHAlHCqRw.crl 1547 Authority Info Access: caIssuers - 1548 rsync://repository.apnic.net/APNIC/ 1549 pvpjvwUeQix2e54X8fGbhmdYMo0/ 1550 q66IrWSGuBE7jqx8PAUHAlHCqRw.cer 1551 Authority Key Identifier: Key Identifier: 1552 ab:ae:88:ad:64:86:b8:11:3b:8e:ac:7c:3c:05:07:02: 1553 51:c2:a9:1c 1554 Authority Key Identifier: Key Identifier g(AKI): 1555 q66IrWSGuBE7jqx8PAUHAlHCqRw 1556 Certificate Policies: 1.3.6.1.5.5.7.14.2 1557 IPv4: 192.0.2.0/24, 1558 IPv6: 2001:DB8::/32 1559 ASNum: 4608, 4777, 9545, 18366-18370 1560 Signature: 1561 c5:e7:b2:f3:62:cb:e3:bc:50:1e:6b:90:13:19:f4:5b: 1562 4a:1c:1c:ab:b5:de:b1:a4:22:e0:28:f5:3b:d0:8c:59: 1563 0f:85:f2:06:a6:ae:22:e6:d0:99:fe:cb:eb:1d:6a:e2: 1564 a3:f1:a2:25:95:ec:a7:7d:96:35:dc:16:a7:2f:f5:b7: 1566 11:ba:97:05:57:5f:5d:07:5a:c8:19:c8:27:d3:f7:a3: 1567 92:66:cb:98:2d:e1:7f:a8:25:96:ab:af:ed:87:02:28: 1568 f5:ae:b6:e3:0c:f7:18:82:70:82:f4:76:54:06:b9:9f: 1569 e1:a5:f7:ae:72:dd:ee:f0:d4:d2:78:bb:61:73:cf:51: 1570 26:9f:ea:e8:20:49:06:ba:0c:ac:1d:f6:07:b8:63:a0: 1571 4d:3d:8e:12:84:3a:d0:ec:94:7e:02:db:d4:85:cf:12: 1572 5c:7b:12:1a:52:ab:3c:ba:00:f2:71:e7:f0:fd:b3:f4: 1573 81:e8:a7:cb:07:ca:3a:a4:24:fe:dc:bb:51:16:6a:28: 1574 33:40:a4:64:60:75:0e:c8:06:c8:5f:e5:98:be:16:a3: 1575 bc:19:e7:b3:4f:00:0a:8e:81:33:dd:4c:a0:fb:f5:1c: 1576 1f:1d:3f:b5:90:8b:ec:98:67:76:95:56:8a:94:45:54: 1577 52:3d:1c:69:4c:6f:8a:9f:09:ec:ef:b0:a9:bc:cf:9d 1579 Appendix B. Example Certificate Revocation List 1581 The following is an example Certificate Revocation List. 1583 CRL Name: q66IrWSGuBE7jqx8PAUHAlHCqRw.crl 1585 Data: 1586 Version: 2 1587 Signature Algorithm: 1588 Hash: SHA256, Encryption: RSA 1589 Issuer: CN=Demo Production APNIC CA - Not for real use, 1590 E=ca@apnic.net 1591 This Update: Thu Jul 27 06:30:34 2006 GMT 1592 Next Update: Fri Jul 28 06:30:34 2006 GMT 1593 Authority Key Identifier: Key Identifier: 1594 ab:ae:88:ad:64:86:b8:11:3b:8e:ac:7c:3c:05: 1595 07:02:51:c2:a9:1c 1596 Authority Key Identifier: Key Identifier g(AKI): 1597 q66IrWSGuBE7jqx8PAUHAlHCqRw 1598 CRLNumber: 4 1599 Revoked Certificates: 1 1600 Serial Number: 1 1601 Revocation Date: Mon Jul 17 05:10:19 2006 GMT 1602 Serial Number: 2 1603 Revocation Date: Mon Jul 17 05:12:25 2006 GMT 1604 Serial Number: 4 1605 Revocation Date: Mon Jul 17 05:40:39 2006 GMT 1606 Signature: 1607 b2:5a:e8:7c:bd:a8:00:0f:03:1a:17:fd:40:2c:46: 1608 0e:d5:64:87:e7:e7:bc:10:7d:b6:3e:39:21:a9:12: 1609 f4:5a:d8:b8:d4:bd:57:1a:7d:2f:7c:0d:c6:4f:27: 1610 17:c8:0e:ae:8c:89:ff:00:f7:81:97:c3:a1:6a:0a: 1611 f7:d2:46:06:9a:d1:d5:4d:78:e1:b7:b0:58:4d:09: 1612 d6:7c:1e:a0:40:af:86:5d:8c:c9:48:f6:e6:20:2e: 1613 b9:b6:81:03:0b:51:ac:23:db:9f:c1:8e:d6:94:54: 1614 66:a5:68:52:ee:dd:0f:10:5d:21:b8:b8:19:ff:29: 1615 6f:51:2e:c8:74:5c:2a:d2:c5:fa:99:eb:c5:c2:a2: 1616 d0:96:fc:54:b3:ba:80:4b:92:7f:85:54:76:c9:12: 1617 cb:32:ea:1d:12:7b:f8:f9:a2:5c:a1:b1:06:8e:d8: 1618 c5:42:61:00:8c:f6:33:11:29:df:6e:b2:cc:c3:7c: 1619 d3:f3:0c:8d:5c:49:a5:fb:49:fd:e7:c4:73:68:0a: 1620 09:0e:6d:68:a9:06:52:3a:36:4f:19:47:83:59:da: 1621 02:5b:2a:d0:8a:7a:33:0a:d5:ce:be:b5:a2:7d:8d: 1622 59:a1:9d:ee:60:ce:77:3d:e1:86:9a:84:93:90:9f: 1623 34:a7:02:40:59:3a:a5:d1:18:fb:6f:fc:af:d4:02: 1624 d9 1626 Appendix C. Cryptographic Message Syntax Profile for RPKI Trust Anchor 1627 Material 1629 Using the Cryptographic Message Syntax (CMS) [RFC3852], a RPKI Trust 1630 Anchor Object (RTA) is a type of signed-data object. The general 1631 format of a CMS object is: 1633 ContentInfo ::= SEQUENCE { 1634 contentType ContentType, 1635 content [0] EXPLICIT ANY DEFINED BY contentType } 1637 ContentType ::= OBJECT IDENTIFIER 1639 As a RTA is a signed-data object, it uses the corresponding OID, 1640 1.2.840.113549.1.7.2. [RFC3852]. 1642 C.1. Signed-Data ContentType 1644 According to the CMS specification, the signed-data content type 1645 shall have ASN.1 type SignedData: 1647 SignedData ::= SEQUENCE { 1648 version CMSVersion, 1649 digestAlgorithms DigestAlgorithmIdentifiers, 1650 encapContentInfo EncapsulatedContentInfo, 1651 certificates [0] IMPLICIT CertificateSet OPTIONAL, 1652 crls [1] IMPLICIT RevocationInfoChoices OPTIONAL, 1653 signerInfos SignerInfos } 1655 DigestAlgorithmIdentifiers ::= SET OF DigestAlgorithmIdentifier 1657 SignerInfos ::= SET OF SignerInfo 1659 The elements of the signed-data content type are as follows: 1661 version 1662 The version is the syntax version number. It MUST be 3, 1663 corresponding to the signerInfo structure having version 1664 number 3. 1666 digestAlgorithms 1667 The digestAlgorithms set MUST include only SHA-256, the OID 1668 for which is 2.16.840.1.101.3.4.2.1. [RFC4055]. It MUST 1669 NOT contain any other algorithms. 1671 encapContentInfo 1672 This element is defined in Appendix C.1.1. 1674 certificates 1675 The certificates element MUST be included and MUST contain 1676 only the single PKI EE certificate needed to validate this 1677 CMS Object. The CertificateSet type is defined in section 1678 10 of [RFC3852] 1680 crls 1681 The crls element MUST be omitted. 1683 signerInfos 1684 This element is defined in Appendix C.1.2. 1686 C.1.1. encapContentInfo 1688 encapContentInfo is the signed content, consisting of a content type 1689 identifier and the content itself. 1691 EncapsulatedContentInfo ::= SEQUENCE { 1692 eContentType ContentType, 1693 eContent [0] EXPLICIT OCTET STRING OPTIONAL } 1695 ContentType ::= OBJECT IDENTIFIER 1697 The elements of this signed content type are as follows: 1699 eContentType 1700 The ContentType for an RTA is defined as id-ct- 1701 RPKITrustAnchor and has the numerical value of 1702 1.2.840.113549.1.9.16.1.33. 1704 id-smime OBJECT IDENTIFIER ::= { iso(1) member-body(2) 1705 us(840) rsadsi(113549) pkcs(1) pkcs9(9) 16 } 1707 id-ct OBJECT IDENTIFIER ::= { id-smime 1 } 1709 id-ct-RPKITrustAnchor OBJECT IDENTIFIER ::= { id-ct 33 } 1711 eContent 1712 The content of an RTA is an RPKI self-signed CA certificate. 1713 It is formally defined as: 1715 id-ct-RPKITrustAnchor ::= Certificate 1717 The definition of Certificate is taken from [X.509]. 1719 C.1.2. signerInfos 1721 SignerInfo is defined under CMS as: 1723 SignerInfo ::= SEQUENCE { 1724 version CMSVersion, 1725 sid SignerIdentifier, 1726 digestAlgorithm DigestAlgorithmIdentifier, 1727 signedAttrs [0] IMPLICIT SignedAttributes OPTIONAL, 1728 signatureAlgorithm SignatureAlgorithmIdentifier, 1729 signature SignatureValue, 1730 unsignedAttrs [1] IMPLICIT UnsignedAttributes OPTIONAL } 1732 The content of the SignerInfo element are as follows: 1734 version 1735 The version number MUST be 3, corresponding with the choice 1736 of SubjectKeyIdentifier for the sid. 1738 sid 1739 The sid is defined as: 1741 SignerIdentifier ::= CHOICE { 1742 issuerAndSerialNumber IssuerAndSerialNumber, 1743 subjectKeyIdentifier [0] SubjectKeyIdentifier } 1745 For a RTA, the sid MUST be a SubjectKeyIdentifier. 1747 digestAlgorithm 1748 The digestAlgorithm MUST be SHA-256, the OID for which is 1749 2.16.840.1.101.3.4.2.1. [RFC4055] 1751 signedAttrs 1752 The signedAttrs element is defined as: 1754 SignedAttributes ::= SET SIZE (1..MAX) OF Attribute 1756 Attribute ::= SEQUENCE { 1757 attrType OBJECT IDENTIFIER, 1758 attrValues SET OF AttributeValue } 1760 AttributeValue ::= ANY 1762 The signedAttr element MUST be present and MUST include the 1763 content-type and message-digest attributes. The signer MAY 1764 also include the signing-time signed attribute, the binary- 1765 signing-time signed attribute, or both signed attributes. 1766 Other signed attributes that are deemed appropriate MAY also 1767 be included. The intent is to allow additional signed 1768 attributes to be included if a future need is identified. 1769 This does not cause an interoperability concern because 1770 unrecognized signed attributes are ignored by the relying 1771 party. 1773 The signedAttr MUST include only a single instance of any 1774 particular attribute. Additionally, even though the syntax 1775 allows for a SET OF AttributeValue, in a RTA the attrValues 1776 must consist of only a single AttributeValue. 1778 ContentType Attribute 1779 The ContentType attribute MUST be present. The 1780 attrType OID for the ContentType attribute is 1781 1.2.840.113549.1.9.3. 1783 The attrValues for the ContentType attribute in 1784 a RTA MUST be 1.2.840.113549.1.9.16.1.24 1785 (matching the eContentType in the 1786 EncapsulatedContentInfo). 1788 MessageDigest Attribute 1789 The MessageDigest attribute MUST be present. 1790 The attrType OID for the MessageDigest Attribute 1791 is 1.2.840.113549.1.9.4. 1793 The attrValues for the MessageDigest attribute 1794 contains the output of the digest algorithm 1795 applied to the content being signed, as 1796 specified in Section 11.1 of [RFC3852]. 1798 SigningTime Attribute 1799 The SigningTime attribute MAY be present. If it 1800 is present it MUST be ignored by the relying 1801 party. The presence of absence of the 1802 SigningTime attribute in no way affects the 1803 validation of the RTA. The attrType OID for the 1804 SigningTime attribute is 1.2.840.113549.1.9.5. 1806 The attrValues for the SigningTime attribute is 1807 defined as: 1809 SigningTime ::= Time 1811 Time ::= CHOICE { 1812 utcTime UTCTime, 1813 generalizedTime GeneralizedTime } 1815 The Time element specifies the time, based on 1816 the local system clock, at which the digital 1817 signature was applied to the content. 1819 BinarySigningTime Attribute 1820 The BinarySigningTime attribute MAY be present. 1821 If it is present it MUST be ignored by the 1822 relying party. The presence of absence of the 1823 BinarySigningTime attribute in no way affects 1824 the validation of the RTA. The attrType OID for 1825 the SigningTime attribute is 1826 1.2.840.113549.1.9.16.2.46. 1828 The attrValues for the SigningTime attribute is 1829 defined as: 1831 BinarySigningTime ::= BinaryTime 1833 BinaryTime ::= INTEGER (0..MAX) 1835 The BinaryTime element specifies the time, based 1836 on the local system clock, at which the digital 1837 signature was applied to the content. 1839 signatureAlgorithm 1840 The signatureAlgorithm MUST be RSA (rsaEncryption), the OID 1841 for which is 1.2.840.113549.1.1.1.q 1843 signature 1844 The signature value is defined as: 1846 SignatureValue ::= OCTET STRING 1848 The signature characteristics are defined by the digest and 1849 signature algorithms. 1851 unsignedAttrs 1852 unsignedAttrs MUST be omitted. 1854 C.2. RTA Validation 1856 Before a relying party can use an RTA, the relying party must first 1857 validate the RTA by performing the following steps. 1859 1. Verify that the RTA syntax complies with this specification. 1860 In particular, verify the following: 1862 a. The contentType of the CMS object is SignedData (OID 1863 1.2.840.113549.1.7.2). 1865 b. The version of the SignedData object is 3. 1867 c. The digestAlgorithm in the SignedData object is SHA-256 1868 (OID 2.16.840.1.101.3.4.2.1). 1870 d. The certificates field in the SignedData object is present 1871 and contains a single EE certificate whose Subject Key 1872 Identifier (SKI) matches the sid field of the SignerInfo 1873 object. 1875 e. The crls field in the SignedData object is omitted. 1877 f. The eContentType in the EncapsulatedContentInfo is id-ct- 1878 RPKITrustAnchor (OID 1.2.840.113549.1.9.16.1.[TBD]) 1880 g. The version of the SignerInfo is 3. 1882 h. The digestAlgorithm in the SignerInfo object is SHA-256 1883 (OID 2.16.840.1.101.3.4.2.1). 1885 i. The signatureAlgorithm in the SignerInfo object is RSA 1886 (OID 1.2.840.113549.1.1.1). 1888 j. The signedAttrs field in the SignerInfo object is present 1889 and contains both the ContentType attribute (OID 1890 1.2.840.113549.1.9.3) and the MessageDigest attribute (OID 1891 1.2.840.113549.1.9.4). 1893 k. The unsignedAttrs field in the SignerInfo object is 1894 omitted. 1896 2. Use the public key in the EE certificate to verify the 1897 signature on the RTA. 1899 3. Verify that the EE certificate is a valid end-entity 1900 certificate in the Trust Anchor PKI by validating that the PKI 1901 CA certificate issued this EE certificate, and the PKI CA's 1902 CRL has not revoked the EE certificate, and that the PKI CA's 1903 CRL is valid. 1905 Authors' Addresses 1907 Geoff Huston 1908 Asia Pacific Network Information Centre 1910 Email: gih@apnic.net 1911 URI: http://www.apnic.net 1913 George Michaelson 1914 Asia Pacific Network Information Centre 1916 Email: ggm@apnic.net 1917 URI: http://www.apnic.net 1919 Robert Loomans 1920 Asia Pacific Network Information Centre 1922 Email: robertl@apnic.net 1923 URI: http://www.apnic.net 1925 Full Copyright Statement 1927 Copyright (C) The IETF Trust (2008). 1929 This document is subject to the rights, licenses and restrictions 1930 contained in BCP 78, and except as set forth therein, the authors 1931 retain all their rights. 1933 This document and the information contained herein are provided on an 1934 "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS 1935 OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY, THE IETF TRUST AND 1936 THE INTERNET ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS 1937 OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF 1938 THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED 1939 WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. 1941 Intellectual Property 1943 The IETF takes no position regarding the validity or scope of any 1944 Intellectual Property Rights or other rights that might be claimed to 1945 pertain to the implementation or use of the technology described in 1946 this document or the extent to which any license under such rights 1947 might or might not be available; nor does it represent that it has 1948 made any independent effort to identify any such rights. 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