idnits 2.17.1 draft-ietf-weirds-rdap-query-15.txt: Checking boilerplate required by RFC 5378 and the IETF Trust (see https://trustee.ietf.org/license-info): ---------------------------------------------------------------------------- No issues found here. Checking nits according to https://www.ietf.org/id-info/1id-guidelines.txt: ---------------------------------------------------------------------------- No issues found here. Checking nits according to https://www.ietf.org/id-info/checklist : ---------------------------------------------------------------------------- No issues found here. Miscellaneous warnings: ---------------------------------------------------------------------------- == The copyright year in the IETF Trust and authors Copyright Line does not match the current year -- The document date (October 7, 2014) is 3487 days in the past. Is this intentional? 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'I-D.ietf-weirds-using-http' ** Downref: Normative reference to an Unknown state RFC: RFC 952 ** Downref: Normative reference to an Informational RFC: RFC 1166 ** Obsolete normative reference: RFC 7230 (Obsoleted by RFC 9110, RFC 9112) ** Obsolete normative reference: RFC 7231 (Obsoleted by RFC 9110) -- Possible downref: Non-RFC (?) normative reference: ref. 'Unicode-UAX15' -- Obsolete informational reference (is this intentional?): RFC 1594 (Obsoleted by RFC 2664) -- Obsolete informational reference (is this intentional?): RFC 7159 (Obsoleted by RFC 8259) Summary: 4 errors (**), 0 flaws (~~), 6 warnings (==), 6 comments (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Network Working Group A. Newton 3 Internet-Draft ARIN 4 Intended status: Standards Track S. Hollenbeck 5 Expires: April 10, 2015 Verisign Labs 6 October 7, 2014 8 Registration Data Access Protocol Query Format 9 draft-ietf-weirds-rdap-query-15 11 Abstract 13 This document describes uniform patterns to construct HTTP URLs that 14 may be used to retrieve registration information from registries 15 (including both Regional Internet Registries (RIRs) and Domain Name 16 Registries (DNRs)) using "RESTful" web access patterns. These 17 uniform patterns define the query syntax for the Registration Data 18 Access Protocol (RDAP). 20 Status of This Memo 22 This Internet-Draft is submitted in full conformance with the 23 provisions of BCP 78 and BCP 79. 25 Internet-Drafts are working documents of the Internet Engineering 26 Task Force (IETF). Note that other groups may also distribute 27 working documents as Internet-Drafts. The list of current Internet- 28 Drafts is at http://datatracker.ietf.org/drafts/current/. 30 Internet-Drafts are draft documents valid for a maximum of six months 31 and may be updated, replaced, or obsoleted by other documents at any 32 time. It is inappropriate to use Internet-Drafts as reference 33 material or to cite them other than as "work in progress." 35 This Internet-Draft will expire on April 10, 2015. 37 Copyright Notice 39 Copyright (c) 2014 IETF Trust and the persons identified as the 40 document authors. All rights reserved. 42 This document is subject to BCP 78 and the IETF Trust's Legal 43 Provisions Relating to IETF Documents 44 (http://trustee.ietf.org/license-info) in effect on the date of 45 publication of this document. Please review these documents 46 carefully, as they describe your rights and restrictions with respect 47 to this document. Code Components extracted from this document must 48 include Simplified BSD License text as described in Section 4.e of 49 the Trust Legal Provisions and are provided without warranty as 50 described in the Simplified BSD License. 52 Table of Contents 54 1. Conventions Used in This Document . . . . . . . . . . . . . . 2 55 1.1. Acronyms and Abbreviations . . . . . . . . . . . . . . . 2 56 2. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 57 3. Path Segment Specification . . . . . . . . . . . . . . . . . 4 58 3.1. Lookup Path Segment Specification . . . . . . . . . . . . 5 59 3.1.1. IP Network Path Segment Specification . . . . . . . . 5 60 3.1.2. Autonomous System Path Segment Specification . . . . 6 61 3.1.3. Domain Path Segment Specification . . . . . . . . . . 6 62 3.1.4. Name Server Path Segment Specification . . . . . . . 7 63 3.1.5. Entity Path Segment Specification . . . . . . . . . . 8 64 3.1.6. Help Path Segment Specification . . . . . . . . . . . 8 65 3.2. Search Path Segment Specification . . . . . . . . . . . . 9 66 3.2.1. Domain Search . . . . . . . . . . . . . . . . . . . . 9 67 3.2.2. Name Server Search . . . . . . . . . . . . . . . . . 10 68 3.2.3. Entity Search . . . . . . . . . . . . . . . . . . . . 11 69 4. Query Processing . . . . . . . . . . . . . . . . . . . . . . 12 70 4.1. Partial String Searching . . . . . . . . . . . . . . . . 12 71 4.2. Associated Records . . . . . . . . . . . . . . . . . . . 13 72 5. Extensibility . . . . . . . . . . . . . . . . . . . . . . . . 13 73 6. Internationalization Considerations . . . . . . . . . . . . . 13 74 6.1. Character Encoding Considerations . . . . . . . . . . . . 14 75 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 15 76 8. Security Considerations . . . . . . . . . . . . . . . . . . . 15 77 9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 15 78 10. References . . . . . . . . . . . . . . . . . . . . . . . . . 16 79 10.1. Normative References . . . . . . . . . . . . . . . . . . 16 80 10.2. Informative References . . . . . . . . . . . . . . . . . 17 81 Appendix A. Change Log . . . . . . . . . . . . . . . . . . . . . 18 82 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 19 84 1. Conventions Used in This Document 86 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 87 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 88 document are to be interpreted as described in RFC 2119 [RFC2119]. 90 1.1. Acronyms and Abbreviations 92 IDN: Internationalized Domain Name 93 IDNA: Internationalized Domain Names in Applications 94 DNR: Domain Name Registry 95 NFC: Unicode Normalization Form C 96 NFKC: Unicode Normalization Form KC 97 RDAP: Registration Data Access Protocol 98 REST: Representational State Transfer State Transfer. The term 99 was first described in a doctoral dissertation [REST]. 100 RESTful: An adjective that describes a service using HTTP and the 101 principles of REST. 102 RIR: Regional Internet Registry 104 2. Introduction 106 This document describes a specification for querying registration 107 data using a RESTful web service and uniform query patterns. The 108 service is implemented using the Hypertext Transfer Protocol (HTTP) 109 [RFC7230] and the conventions described in 110 [I-D.ietf-weirds-using-http]. These uniform patterns define the 111 query syntax for the Registration Data Access Protocol (RDAP). 113 The protocol described in this specification is intended to address 114 deficiencies with the WHOIS protocol [RFC3912] that have been 115 identified over time, including: 117 o Lack of standardized command structures, 118 o lack of standardized output and error structures, 119 o lack of support for internationalization and localization, and 120 o lack of support for user identification, authentication, and 121 access control. 123 The patterns described in this document purposefully do not encompass 124 all of the methods employed in the WHOIS and other RESTful web 125 services of all of the RIRs and DNRs. The intent of the patterns 126 described here are to enable queries of: 128 o networks by IP address, 129 o autonomous system numbers by number, 130 o reverse DNS meta-data by domain, 131 o name servers by name, 132 o registrars by name, and 133 o entities (such as contacts) by identifier. 135 Server implementations are free to support only a subset of these 136 features depending on local requirements. If a server receives a 137 query that it cannot process because it is not implemented it SHOULD 138 return an HTTP 501 [RFC7231] error. It is also envisioned that each 139 registry will continue to maintain WHOIS and/or other RESTful web 140 services specific to their needs and those of their constituencies, 141 and the information retrieved through the patterns described here may 142 reference such services. 144 Likewise, future IETF standards may add additional patterns for 145 additional query types. A simple pattern namespacing scheme is 146 described in Section 5 to accommodate custom extensions that will not 147 interfere with the patterns defined in this document or patterns 148 defined in future IETF standards. 150 WHOIS services, in general, are read-only services. Therefore URL 151 [RFC3986] patterns specified in this document are only applicable to 152 the HTTP [RFC7231] GET and HEAD methods. 154 This document does not describe the results or entities returned from 155 issuing the described URLs with an HTTP GET. The specification of 156 these entities is described in [I-D.ietf-weirds-json-response]. 158 Additionally, resource management, provisioning and update functions 159 are out of scope for this document. Registries have various and 160 divergent methods covering these functions, and it is unlikely a 161 uniform approach for these functions will ever be possible. 163 HTTP contains mechanisms for servers to authenticate clients and for 164 clients to authenticate servers (from which authorization schemes may 165 be built) so such mechanisms are not described in this document. 166 Policy, provisioning, and processing of authentication and 167 authorization are out-of-scope for this document as deployments will 168 have to make choices based on local criteria. Supported 169 authentication mechanisms are described in 170 [I-D.ietf-weirds-rdap-sec]. 172 3. Path Segment Specification 174 The base URLs used to construct RDAP queries are maintained in an 175 IANA registry described in [I-D.ietf-weirds-bootstrap]. Queries are 176 formed by retrieving the appropriate base URL from the registry and 177 appending a path segment specified in either Section 3.1 or 178 Section 3.2. Generally, a registry or other service provider will 179 provide a base URL that identifies the protocol, host and port, and 180 this will be used as a base URL that the complete URL is resolved 181 against, as per Section 5 of RFC 3986 [RFC3986]. For example, if the 182 base URL is "http://example.com/rdap/", all RDAP query URLs will 183 begin with "http://example.com/rdap/". 185 The bootstrap registry does not contain information for query objects 186 that are not part of a global namespace, including entities and help. 187 A base URL for an associated object is required to construct a 188 complete query. 190 For entities, a base URL is retrieved for the service (domain, 191 address, etc.) associated with a given entity. The query URL is 192 constructed by concatenating the base URL to the entity path segment 193 specified in either Section 3.1.5 or Section 3.2.3. 195 For help, a base URL is retrieved for any service (domain, address, 196 etc.) for which additional information is required. The query URL is 197 constructed by concatenating the base URL to the help path segment 198 specified in either Section 3.1.6. 200 3.1. Lookup Path Segment Specification 202 The resource type path segments for exact match lookup are: 204 o 'ip': Used to identify IP networks and associated data referenced 205 using either an IPv4 or IPv6 address. 206 o 'autnum': Used to identify autonomous system registrations and 207 associated data referenced using an AS Plain autonomous system 208 number. 209 o 'domain': Used to identify reverse DNS (RIR) or domain name (DNR) 210 information and associated data referenced using a fully-qualified 211 domain name. 212 o 'nameserver': Used to identify a name server information query 213 using a host name. 214 o 'entity': Used to identify an entity information query using a 215 string identifier. 217 3.1.1. IP Network Path Segment Specification 219 Syntax: ip/ or ip// 221 Queries for information about IP networks are of the form /ip/XXX/... 222 or /ip/XXX/YY/... where the path segment following 'ip' is either an 223 IPv4 dotted-decimal or IPv6 [RFC5952] address (i.e. XXX) or an IPv4 224 or IPv6 CIDR [RFC4632] notation address block (i.e. XXX/YY). 225 Semantically, the simpler form using the address can be thought of as 226 a CIDR block with a bitmask length of 32 for IPv4 and a bitmask 227 length of 128 for IPv6. A given specific address or CIDR may fall 228 within multiple IP networks in a hierarchy of networks, therefore 229 this query targets the "most-specific" or smallest IP network which 230 completely encompasses it in a hierarchy of IP networks. 232 The IPv4 and IPv6 address formats supported in this query are 233 described in section 3.2.2 of [RFC3986], as IPv4address and 234 IPv6address ABNF definitions. Any valid IPv6 text address format 235 [RFC4291] can be used, compressed or not compressed. The restricted 236 rules to write a text representation of an IPv6 address [RFC5952] are 237 not mandatory. However, the zone id [RFC4007] is not appropriate in 238 this context and therefore prohibited. 240 For example, the following URL would be used to find information for 241 the most specific network containing 192.0.2.0: 243 http://example.com/rdap/ip/192.0.2.0 245 The following URL would be used to find information for the most 246 specific network containing 192.0.2.0/24: 248 http://example.com/rdap/ip/192.0.2.0/24 250 The following URL would be used to find information for the most 251 specific network containing 2001:db8::0: 253 http://example.com/rdap/ip/2001:db8::0 255 3.1.2. Autonomous System Path Segment Specification 257 Syntax: autnum/ 259 Queries for information regarding autonomous system number 260 registrations are of the form /autnum/XXX/... where XXX is an AS 261 Plain autonomous system number [RFC5396]. In some registries, 262 registration of autonomous system numbers is done on an individual 263 number basis, while other registries may register blocks of 264 autonomous system numbers. The semantics of this query are such that 265 if a number falls within a range of registered blocks, the target of 266 the query is the block registration, and that individual number 267 registrations are considered a block of numbers with a size of 1. 269 For example, the following URL would be used to find information 270 describing autonomous system number 12 (a number within a range of 271 registered blocks): 273 http://example.com/rdap/autnum/12 275 The following URL would be used to find information describing 4-byte 276 autonomous system number 65538: 278 http://example.com/rdap/autnum/65538 280 3.1.3. Domain Path Segment Specification 282 Syntax: domain/ 284 Queries for domain information are of the form /domain/XXXX/..., 285 where XXXX is a fully-qualified (relative to the root) domain name 286 [RFC1594] in either the in-addr.arpa or ip6.arpa zones (for RIRs) or 287 a fully-qualified domain name in a zone administered by the server 288 operator (for DNRs). Internationalized domain names represented in 289 either A-label or U-label format [RFC5890] are also valid domain 290 names. See Section 6.1 for information on character encoding for the 291 U-label format. 293 IDNs SHOULD NOT be represented as a mixture of A-labels and U-labels; 294 that is, all internationalized labels in an IDN SHOULD be either 295 A-labels or U-labels. It is possible for an RDAP client to assemble 296 a query string from multiple independent data sources. Such a client 297 might not be able to perform conversions between A-labels and 298 U-labels. An RDAP server that receives a query string with a mixture 299 of A-labels and U-labels MAY convert all the U-labels to A-labels, 300 perform IDNA processing, and proceed with exact-match lookup. In 301 such cases, the response to be returned to the query source may not 302 match the input from the query source. Alternatively, the server MAY 303 refuse to process the query. 305 The server MAY perform the match using either the A-label or U-label 306 form. Using one consistent form for matching every label is likely 307 to be more reliable. 309 The following URL would be used to find information describing the 310 zone serving the network 192.0.2/24: 312 http://example.com/rdap/domain/2.0.192.in-addr.arpa 314 The following URL would be used to find information describing the 315 zone serving the network 2001:db8:1::/48: 317 http://example.com/rdap/domain/1.0.0.0.8.b.d.0.1.0.0.2.ip6.arpa 319 The following URL would be used to find information for the 320 blah.example.com domain name: 322 http://example.com/rdap/domain/blah.example.com 324 The following URL would be used to find information for the 325 xn--fo-5ja.example IDN: 327 http://example.com/rdap/domain/xn--fo-5ja.example 329 3.1.4. Name Server Path Segment Specification 331 Syntax: nameserver/ 333 The parameter represents a fully qualified name as 334 specified in RFC 952 [RFC0952] and RFC 1123 [RFC1123]. 335 Internationalized names represented in either A-label or U-label 336 format [RFC5890] are also valid name server names. IDN processing 337 for name server names uses the domain name processing instructions 338 specified in Section 3.1.3. See Section 6.1 for information on 339 character encoding for the U-label format. 341 The following URL would be used to find information for the 342 ns1.example.com name server: 344 http://example.com/rdap/nameserver/ns1.example.com 346 The following URL would be used to find information for the 347 ns1.xn--fo-5ja.example name server: 349 http://example.com/rdap/nameserver/ns1.xn--fo-5ja.example 351 3.1.5. Entity Path Segment Specification 353 Syntax: entity/ 355 The parameter represents an entity (such as a contact, 356 registrant, or registrar) identifier whose syntax is specific to the 357 registration provider. For example, for some DNRs contact 358 identifiers are specified in RFC 5730 [RFC5730] and RFC 5733 359 [RFC5733]. 361 The following URL would be used to find information for the entity 362 associated with handle XXXX: 364 http://example.com/rdap/entity/XXXX 366 3.1.6. Help Path Segment Specification 368 Syntax: help 370 The help path segment can be used to request helpful information 371 (command syntax, terms of service, privacy policy, rate limiting 372 policy, supported authentication methods, supported extensions, 373 technical support contact, etc.) from an RDAP server. The response 374 to "help" should provide basic information that a client needs to 375 successfully use the service. The following URL would be used to 376 return "help" information: 378 http://example.com/rdap/help 380 3.2. Search Path Segment Specification 382 A simple search to determine if an object exists (or not) without 383 returning RDAP-encoded results can be performed using the HTTP HEAD 384 method as described in Section 4.1 of [I-D.ietf-weirds-using-http]. 386 The resource type path segments for search are: 388 o 'domains': Used to identify a domain name information search using 389 a pattern to match a fully-qualified domain name. 390 o 'nameservers': Used to identify a name server information search 391 using a pattern to match a host name. 392 o 'entities': Used to identify an entity information search using a 393 pattern to match a string identifier. 395 RDAP search path segments are formed using a concatenation of the 396 plural form of the object being searched for and an HTTP query 397 string. The HTTP query string is formed using a concatenation of the 398 question mark character ('?', ASCII value 0x003F), the JSON object 399 value associated with the object being searched for, the equal sign 400 character ('=', ASCII value 0x003D), and the search pattern. Search 401 pattern query processing is described more fully in Section 4. For 402 the domain and entity objects described in this document the plural 403 object forms are "domains" and "entities". 405 Detailed results can be retrieved using the HTTP GET method and the 406 path segments specified here. 408 3.2.1. Domain Search 410 Syntax: domains?name= 412 Syntax: domains?nsLdhName= 414 Syntax: domains?nsIp= 416 Searches for domain information by name are specified using this 417 form: 419 /domains?name=XXXX 421 XXXX is a search pattern representing a domain name in "letters, 422 digits, hyphen" format [RFC5890] in a zone administered by the server 423 operator of a DNR. The following URL would be used to find DNR 424 information for domain names matching the "example*.com" pattern: 426 http://example.com/rdap/domains?name=example*.com 427 Internationalized Domain Names (IDNs) in U-label format [RFC5890] can 428 also be used as search patterns (see Section 4). Searches for these 429 names are of the form /domains?name=XXXX, where XXXX is a search 430 pattern representing a domain name in U-label format [RFC5890]. See 431 Section 6.1 for information on character encoding for the U-label 432 format. 434 Searches for domain information by name server name are specified 435 using this form: 437 /domains?nsLdhName=YYYY 439 YYYY is a search pattern representing a host name in "letters, 440 digits, hyphen" format [RFC5890] in a zone administered by the server 441 operator of a DNR. The following URL would be used to search for 442 domains delegated to name servers matching the "ns1.example*.com" 443 pattern: 445 http://example.com/rdap/domains?nsLdhName=ns1.example*.com 447 Searches for domain information by name server IP address are 448 specified using this form: 450 /domains?nsIp=ZZZZ 452 ZZZZ is a search pattern representing an IPv4 [RFC1166] or IPv6 453 [RFC5952] address. The following URL would be used to search for 454 domains that have been delegated to name servers that resolve to the 455 "192.0.2.0" address: 457 http://example.com/rdap/domains?nsIp=192.0.2.0 459 3.2.2. Name Server Search 461 Syntax: nameservers?name= 463 Syntax: nameservers?ip= 465 Searches for name server information by name server name are 466 specified using this form: 468 /nameservers?name=XXXX 470 XXXX is a search pattern representing a host name in "letters, 471 digits, hyphen" format [RFC5890] in a zone administered by the server 472 operator of a DNR. The following URL would be used to find DNR 473 information for name server names matching the "ns1.example*.com" 474 pattern: 476 http://example.com/rdap/nameservers?name=ns1.example*.com 478 Internationalized name server names in U-label format [RFC5890] can 479 also be used as search patterns (see Section 4). Searches for these 480 names are of the form /nameservers?name=XXXX, where XXXX is a search 481 pattern representing a name server name in U-label format [RFC5890]. 482 See Section 6.1 for information on character encoding for the U-label 483 format. 485 Searches for name server information by name server IP address are 486 specified using this form: 488 /nameservers?ip=YYYY 490 YYYY is a search pattern representing an IPv4 [RFC1166] or IPv6 491 [RFC5952] address. The following URL would be used to search for 492 name server names that resolve to the "192.0.2.0" address: 494 http://example.com/rdap/nameservers?ip=192.0.2.0 496 3.2.3. Entity Search 498 Syntax: entities?fn= 500 Syntax: entities?handle= 502 Searches for entity information by name are specified using this 503 form: 505 /entities?fn=XXXX 507 where XXXX is a search pattern representing an entity name as 508 specified in Section 6.1 of [I-D.ietf-weirds-json-response]. The 509 following URL would be used to find information for entity names 510 matching the "Bobby Joe*" pattern. 512 http://example.com/rdap/entities?fn=Bobby%20Joe* 514 Searches for entity information by handle are specified using this 515 form: 517 /entities?handle=XXXX 519 where XXXX is a search pattern representing an entity handle as 520 specified in Section 6.1 of [I-D.ietf-weirds-json-response]. The 521 following URL would be used to find information for entity names 522 matching the "CID-40*" pattern. 524 http://example.com/rdap/entities?handle=CID-40* 526 URLs MUST be properly encoded according to the rules of [RFC3986]. 527 In the example above, "Bobby Joe*" is encoded to "Bobby%20Joe*". 529 4. Query Processing 531 Servers indicate the success or failure of query processing by 532 returning an appropriate HTTP response code to the client. Response 533 codes not specifically identified in this document are described in 534 [I-D.ietf-weirds-using-http]. 536 4.1. Partial String Searching 538 Partial string searching uses the asterisk ('*', ASCII value 0x002A) 539 character to match zero or more trailing characters. A character 540 string representing multiple domain name labels MAY be concatenated 541 to the end of the search pattern to limit the scope of the search. 542 For example, the search pattern "exam*" will match "example.com" and 543 "example.net". The search pattern "exam*.com" will match 544 "example.com". Note that these search patterns include implied 545 beginning and end of string regular expression markers, and the 546 "example*.com" search would be translated into a POSIX regular 547 expression as "^example.*\.com$". Additional pattern matching 548 processing is beyond the scope of this specification. 550 If a server receives a search request but cannot process the request 551 because it does not support a particular style of partial match 552 searching, it SHOULD return an HTTP 422 [RFC4918] error. When 553 returning a 422 error, the server MAY also return an error response 554 body as specified in Section 7 of [I-D.ietf-weirds-json-response] if 555 the requested media type is one that is specified in 556 [I-D.ietf-weirds-using-http]. 558 Partial matching is not feasible across combinations of Unicode 559 characters because Unicode characters can be combined with another 560 Unicode character or characters. Servers SHOULD NOT partially match 561 combinations of Unicode characters where a Unicode character may be 562 legally combined with another Unicode character or characters. It 563 should be noted, though, that it may not always be possible to detect 564 possible cases where a character could have been combined with 565 another character, but was not, because of the way combining 566 characters can be combined with many other characters. 568 Clients should avoid submitting a partial match search of Unicode 569 characters where a Unicode character may be legally combined with 570 another Unicode character or characters. Partial match searches with 571 incomplete combinations of characters where a character must be 572 combined with another character or characters are invalid. Partial 573 match searches with characters that may be combined with another 574 character or characters are to be considered non-combined characters 575 (that is, if character x may be combined with character y but 576 character y is not submitted in the search string then character x is 577 a complete character and no combinations of character x are to be 578 searched). 580 4.2. Associated Records 582 Conceptually, a name-record in a database may include a link to an 583 associated name-record, which may include a link to another such 584 record, and so on. If an implementation is to return more than one 585 name-record in response to a query, information from the records 586 thereby identified is returned. 588 Note that this model includes arrangements for associated names, 589 including those that are linked by policy mechanisms and names bound 590 together for some other purposes. Note also that returning 591 information that was not explicitly selected by an exact-match 592 lookup, including additional names that match a relatively fuzzy 593 search as well as lists of names that are linked together, may cause 594 privacy issues. 596 5. Extensibility 598 This document describes path segment specifications for a limited 599 number of objects commonly registered in both RIRs and DNRs. It does 600 not attempt to describe path segments for all of the objects 601 registered in all registries. Custom path segments can be created 602 for objects not specified here using the process described in 603 Section 6 of "HTTP usage in the Registration Data Access Protocol 604 (RDAP)" [I-D.ietf-weirds-using-http]. 606 Custom path segments can be created by prefixing the segment with a 607 unique identifier followed by an underscore character (0x5F). For 608 example, a custom entity path segment could be created by prefixing 609 "entity" with "custom_", producing "custom_entity". Servers MUST 610 return an appropriate failure status code for a request with an 611 unrecognized path segment. 613 6. Internationalization Considerations 615 There is value in supporting the ability to submit either a U-label 616 (Unicode form of an IDN label) or an A-label (ASCII form of an IDN 617 label) as a query argument to an RDAP service. Clients capable of 618 processing non-ASCII characters may prefer a U-label since this is 619 more visually recognizable and familiar than A-label strings, but 620 clients using programmatic interfaces might find it easier to submit 621 and display A-labels if they are unable to input U-labels with their 622 keyboard configuration. Both query forms are acceptable. 624 Internationalized domain and name server names can contain character 625 variants and variant labels as described in RFC 4290 [RFC4290]. 626 Clients that support queries for internationalized domain and name 627 server names MUST accept service provider responses that describe 628 variants as specified in "JSON Responses for the Registration Data 629 Access Protocol" [I-D.ietf-weirds-json-response]. 631 6.1. Character Encoding Considerations 633 Servers can expect to receive search patterns from clients that 634 contain character strings encoded in different forms supported by 635 HTTP. It is entirely possible to apply filters and normalization 636 rules to search patterns prior to making character comparisons, but 637 this type of processing is more typically needed to determine the 638 validity of registered strings than to match patterns. 640 An RDAP client submitting a query string containing non-US-ASCII 641 characters converts such strings into Unicode in UTF-8 encoding. It 642 then performs any local case mapping deemed necessary. Strings are 643 normalized using Normalization Form C (NFC, [Unicode-UAX15]); note 644 that clients might not be able to do this reliably. UTF-8 encoded 645 strings are then appropriately percent-encoded [RFC3986] in the query 646 URL. 648 After parsing any percent-encoding, an RDAP server treats each query 649 string as Unicode in UTF-8 encoding. If a string is not valid UTF-8, 650 the server can immediately stop processing the query and return an 651 HTTP 400 error response code. 653 When processing queries, there is a difference in handling DNS names, 654 including those including putative U-labels, and everything else. 655 DNS names are treated according to the DNS matching rules as 656 described in Section 3.1 of RFC 1035 [RFC1035] for NR-LDH labels and 657 the matching rules described in Section 5.4 of RFC 5891 [RFC5891] for 658 U-labels. Matching of DNS names proceeds one label at a time, 659 because it is possible for a combination of U-labels and NR-LDH 660 labels to be found in a single domain or host name. The 661 determination of whether a label is a U-label or an NR-LDH label is 662 based on whether the label contains any characters outside of the US- 663 ASCII letters, digits, or hyphen (the so-called LDH rule). 665 For everything else, servers map fullwidth and halfwidth characters 666 to their decomposition equivalents. Servers convert strings to the 667 same coded character set of the target data that is to be looked up 668 or searched and each string is normalized using the same 669 normalization that was used on the target data. In general, storage 670 of strings as Unicode is RECOMMENDED. For the purposes of 671 comparison, Normalization Form KC (NFKC, [Unicode-UAX15]) with case 672 folding is used to maximize predictability and the number of matches. 673 Note the use of case-folded NFKC as opposed to NFC in this case. 675 7. IANA Considerations 677 This document does not specify any IANA actions. 679 8. Security Considerations 681 Security services for the operations specified in this document are 682 described in "Security Services for the Registration Data Access 683 Protocol" [I-D.ietf-weirds-rdap-sec]. 685 Search functionality typically requires more server resources (such 686 as memory, CPU cycles, and network bandwidth) when compared to basic 687 lookup functionality. This increases the risk of server resource 688 exhaustion and subsequent denial of service due to abuse. This risk 689 can be mitigated by developing and implementing controls to restrict 690 search functionality to identified and authorized clients. If those 691 clients behave badly, their search privileges can be suspended or 692 revoked. Rate limiting as described in Section 5.5 of "HTTP usage in 693 the Registration Data Access Protocol (RDAP)" 694 [I-D.ietf-weirds-using-http] can also be used to control the rate of 695 received search requests. Server operators can also reduce their 696 risk by restricting the amount of information returned in response to 697 a search request. 699 Search functionality also increases the privacy risk of disclosing 700 object relationships that might not otherwise be obvious. For 701 example, a search that returns IDN variants [RFC6927] that do not 702 explicitly match a client-provided search pattern can disclose 703 information about registered domain names that might not be otherwise 704 available. Implementers need to consider the policy and privacy 705 implications of returning information that was not explicitly 706 requested. 708 9. Acknowledgements 710 This document is derived from original work on RIR query formats 711 developed by Byron J. Ellacott of APNIC, Arturo L. Servin of 712 LACNIC, Kaveh Ranjbar of the RIPE NCC, and Andrew L. Newton of ARIN. 713 Additionally, this document incorporates DNR query formats originally 714 described by Francisco Arias and Steve Sheng of ICANN and Scott 715 Hollenbeck of Verisign Labs. 717 The authors would like to acknowledge the following individuals for 718 their contributions to this document: Francisco Arias, Marc Blanchet, 719 Ernie Dainow, Jean-Philippe Dionne, Behnam Esfahbod, John Klensin, 720 Edward Lewis, John Levine, Mark Nottingham, and Andrew Sullivan. 722 10. References 724 10.1. Normative References 726 [I-D.ietf-weirds-bootstrap] 727 Blanchet, M. and G. Leclanche, "Finding the Authoritative 728 Registration Data (RDAP) Service", draft-ietf-weirds- 729 bootstrap-07 (work in progress), September 2014. 731 [I-D.ietf-weirds-json-response] 732 Newton, A. and S. Hollenbeck, "JSON Responses for the 733 Registration Data Access Protocol (RDAP)", draft-ietf- 734 weirds-json-response-09 (work in progress), September 735 2014. 737 [I-D.ietf-weirds-rdap-sec] 738 Hollenbeck, S. and N. Kong, "Security Services for the 739 Registration Data Access Protocol", draft-ietf-weirds- 740 rdap-sec-09 (work in progress), September 2014. 742 [I-D.ietf-weirds-using-http] 743 Newton, A., Ellacott, B., and N. Kong, "HTTP usage in the 744 Registration Data Access Protocol (RDAP)", draft-ietf- 745 weirds-using-http-12 (work in progress), September 2014. 747 [RFC0952] Harrenstien, K., Stahl, M., and E. Feinler, "DoD Internet 748 host table specification", RFC 952, October 1985. 750 [RFC1035] Mockapetris, P., "Domain names - implementation and 751 specification", STD 13, RFC 1035, November 1987. 753 [RFC1123] Braden, R., "Requirements for Internet Hosts - Application 754 and Support", STD 3, RFC 1123, October 1989. 756 [RFC1166] Kirkpatrick, S., Stahl, M., and M. Recker, "Internet 757 numbers", RFC 1166, July 1990. 759 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 760 Requirement Levels", BCP 14, RFC 2119, March 1997. 762 [RFC3986] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform 763 Resource Identifier (URI): Generic Syntax", STD 66, RFC 764 3986, January 2005. 766 [RFC4291] Hinden, R. and S. Deering, "IP Version 6 Addressing 767 Architecture", RFC 4291, February 2006. 769 [RFC4632] Fuller, V. and T. Li, "Classless Inter-domain Routing 770 (CIDR): The Internet Address Assignment and Aggregation 771 Plan", BCP 122, RFC 4632, August 2006. 773 [RFC4918] Dusseault, L., "HTTP Extensions for Web Distributed 774 Authoring and Versioning (WebDAV)", RFC 4918, June 2007. 776 [RFC5396] Huston, G. and G. Michaelson, "Textual Representation of 777 Autonomous System (AS) Numbers", RFC 5396, December 2008. 779 [RFC5730] Hollenbeck, S., "Extensible Provisioning Protocol (EPP)", 780 STD 69, RFC 5730, August 2009. 782 [RFC5733] Hollenbeck, S., "Extensible Provisioning Protocol (EPP) 783 Contact Mapping", STD 69, RFC 5733, August 2009. 785 [RFC5890] Klensin, J., "Internationalized Domain Names for 786 Applications (IDNA): Definitions and Document Framework", 787 RFC 5890, August 2010. 789 [RFC5891] Klensin, J., "Internationalized Domain Names in 790 Applications (IDNA): Protocol", RFC 5891, August 2010. 792 [RFC5952] Kawamura, S. and M. Kawashima, "A Recommendation for IPv6 793 Address Text Representation", RFC 5952, August 2010. 795 [RFC7230] Fielding, R. and J. Reschke, "Hypertext Transfer Protocol 796 (HTTP/1.1): Message Syntax and Routing", RFC 7230, June 797 2014. 799 [RFC7231] Fielding, R. and J. Reschke, "Hypertext Transfer Protocol 800 (HTTP/1.1): Semantics and Content", RFC 7231, June 2014. 802 [Unicode-UAX15] 803 The Unicode Consortium, "Unicode Standard Annex #15: 804 Unicode Normalization Forms", September 2013, 805 . 807 10.2. Informative References 809 [REST] Fielding, R. and R. Taylor, "Principled Design of the 810 Modern Web Architecture", ACM Transactions on Internet 811 Technology Vol. 2, No. 2, May 2002. 813 [RFC1594] Marine, A., Reynolds, J., and G. Malkin, "FYI on Questions 814 and Answers - Answers to Commonly asked "New Internet 815 User" Questions", RFC 1594, March 1994. 817 [RFC3912] Daigle, L., "WHOIS Protocol Specification", RFC 3912, 818 September 2004. 820 [RFC4007] Deering, S., Haberman, B., Jinmei, T., Nordmark, E., and 821 B. Zill, "IPv6 Scoped Address Architecture", RFC 4007, 822 March 2005. 824 [RFC4290] Klensin, J., "Suggested Practices for Registration of 825 Internationalized Domain Names (IDN)", RFC 4290, December 826 2005. 828 [RFC6927] Levine, J. and P. Hoffman, "Variants in Second-Level Names 829 Registered in Top-Level Domains", RFC 6927, May 2013. 831 [RFC7159] Bray, T., "The JavaScript Object Notation (JSON) Data 832 Interchange Format", RFC 7159, March 2014. 834 Appendix A. Change Log 836 Initial -00: Adopted as working group document. 837 -01: Added "Conventions Used in This Document" section. Added 838 normative reference to draft-ietf-weirds-rdap-sec and some 839 wrapping text in the Security Considerations section. 840 -02: Removed "unified" from the title. Rewrote the last paragraph 841 of section 2. Edited the first paragraph of section 3 to more 842 clearly note that only one path segment is provided. Added 843 "bitmask" to "length" in section 3.1. Changed "lowest IP network" 844 to "smallest IP network" in section 3.1. Added "asplain" to the 845 description of autonomous system numbers in section 3.2. Minor 846 change from "semantics is" to "semantics are" in section 3.2. 847 Changed the last sentence in section 4 to more clearly specify 848 error response behavior. Added acknowledgements. Added a 849 paragraph in the introduction regarding future IETF standards and 850 extensibility. 851 -03: Changed 'query' to 'lookup' in document title to better 852 describe the 'exact match lookup' purpose of this document. 853 Included a multitude of minor additions and clarifications 854 provided by Marc Blanchet and Jean-Philippe Dionne. Modified the 855 domain and name server sections to include support for IDN 856 U-labels. 857 -04: Updated the domain and name server sections to use .example IDN 858 U-labels. Added text to note that mixed IDN labels SHOULD NOT be 859 used. Fixed broken sentences in Section 6. 860 -05: Added "help" path segment. 862 -06: Added search text and removed or edited old search text. 863 -07: Fixed query parameter typo by replacing "/?" with "?". Changed 864 "asplain" to "AS Plain". Added entity search by handle. 865 Corrected section references. Updated IDN search text. 866 -08: Revised URI formats and added IANA instructions to create a 867 registry entry for the "rdap" well-known prefix. Revised search 868 processing text and added search privacy consideration. 869 Synchronized examples with response draft. 870 -09: More search processing and URI prefix updates. Updated fully- 871 qualified domain name reference. 872 -10: Added name server search by IP address. 873 -11: Replaced reference to RFC 4627 with reference to RFC 7159. 874 Replaced .well-known with bootstrap-defined prefix. Replaced 875 references to RFC 2616 with references to RFC 7231 and draft-ietf- 876 httpbis-http2, adding a note to make it clear that 2616 is an 877 acceptable reference if http2 isn't ready when needed. 878 -12: IDN label processing clarification. Added domain search by 879 name server name and name server IP address. Minor text editing 880 for consistency in the search sections. Replaced reference to 881 draft-ietf-httpbis-http2 with a reference to RFC 7230 and removed 882 reference note. 883 -13: Added HTTP HEAD reference in Section 3.2. 884 -14: Address WG last call comments. 885 -15: Address AD review comments. 887 Authors' Addresses 889 Andrew Lee Newton 890 American Registry for Internet Numbers 891 3635 Concorde Parkway 892 Chantilly, VA 20151 893 US 895 Email: andy@arin.net 896 URI: http://www.arin.net 898 Scott Hollenbeck 899 Verisign Labs 900 12061 Bluemont Way 901 Reston, VA 20190 902 US 904 Email: shollenbeck@verisign.com 905 URI: http://www.verisignlabs.com/