draft-ietf-regext-rdap-reverse-search-10.txt   draft-ietf-regext-rdap-reverse-search-11.txt 
Registration Protocols Extensions M. Loffredo Registration Protocols Extensions M. Loffredo
Internet-Draft M. Martinelli Internet-Draft M. Martinelli
Intended status: Standards Track IIT-CNR/Registro.it Intended status: Standards Track IIT-CNR/Registro.it
Expires: 10 October 2022 8 April 2022 Expires: 3 November 2022 2 May 2022
Registration Data Access Protocol (RDAP) Reverse search capabilities Registration Data Access Protocol (RDAP) Reverse search capabilities
draft-ietf-regext-rdap-reverse-search-10 draft-ietf-regext-rdap-reverse-search-11
Abstract Abstract
The Registration Data Access Protocol (RDAP) does not include query The Registration Data Access Protocol (RDAP) does not include query
capabilities to find the list of domains related to a set of entities capabilities for finding the list of domains related to a set of
matching a given search pattern. In the RDAP context, an entity can entities matching a given search pattern. In the RDAP context, an
be associated with any defined object class. Moreover, other entity can be associated with any defined object class. Moreover,
relationships between object classes exist and might be used for other relationships between object classes exist and might be used
providing a reverse search capability. Therefore, a reverse search for providing a reverse search capability. Therefore, a reverse
can be applied to other use cases than the classic domain-entity search can be applied to other use cases than the classic domain-
scenario. This document describes RDAP query extensions that allow entity scenario. This document describes an RDAP extension that
servers to provide a reverse search feature based on the relationship allow servers to provide a reverse search feature based on the
defined in RDAP between an object class for search and any related relationship defined in RDAP between an object class for search and
object class. The reverse search based on the domain-entity any related object class. The reverse search based on the domain-
relationship is treated as a particular case but with a special focus entity relationship is treated as a particular case.
on its privacy implications.
Status of This Memo Status of This Memo
This Internet-Draft is submitted in full conformance with the This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79. provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute Task Force (IETF). Note that other groups may also distribute
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This Internet-Draft will expire on 10 October 2022. This Internet-Draft will expire on 3 November 2022.
Copyright Notice Copyright Notice
Copyright (c) 2022 IETF Trust and the persons identified as the Copyright (c) 2022 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
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Please review these documents carefully, as they describe your rights Please review these documents carefully, as they describe your rights
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Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Conventions Used in This Document . . . . . . . . . . . . 4 1.1. Conventions Used in This Document . . . . . . . . . . . . 4
2. RDAP Path Segment Specification . . . . . . . . . . . . . . . 4 2. RDAP Path Segment Specification . . . . . . . . . . . . . . . 4
2.1. Reverse Searches Based on Entity Details . . . . . . . . 4 3. RDAP Response Specification . . . . . . . . . . . . . . . . . 5
3. RDAP Conformance . . . . . . . . . . . . . . . . . . . . . . 6 4. Reverse Searches Based on Entity Details . . . . . . . . . . 5
4. Implementation Considerations . . . . . . . . . . . . . . . . 6 5. RDAP Conformance . . . . . . . . . . . . . . . . . . . . . . 6
5. Implementation Status . . . . . . . . . . . . . . . . . . . . 6 6. Implementation Considerations . . . . . . . . . . . . . . . . 6
5.1. IIT-CNR/Registro.it RDAP Server . . . . . . . . . . . . . 7 7. Implementation Status . . . . . . . . . . . . . . . . . . . . 7
5.2. IIT-CNR/Registro.it RDAP Client . . . . . . . . . . . . . 7 7.1. IIT-CNR/Registro.it RDAP Server . . . . . . . . . . . . . 7
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7 7.2. IIT-CNR/Registro.it RDAP Client . . . . . . . . . . . . . 7
7. Privacy Considerations . . . . . . . . . . . . . . . . . . . 8 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 8
8. Security Considerations . . . . . . . . . . . . . . . . . . . 8 9. Privacy Considerations . . . . . . . . . . . . . . . . . . . 8
9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 8 10. Security Considerations . . . . . . . . . . . . . . . . . . . 9
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 9 11. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 9
10.1. Normative References . . . . . . . . . . . . . . . . . . 9 12. References . . . . . . . . . . . . . . . . . . . . . . . . . 9
10.2. Informative References . . . . . . . . . . . . . . . . . 10 12.1. Normative References . . . . . . . . . . . . . . . . . . 9
12.2. Informative References . . . . . . . . . . . . . . . . . 10
Appendix A. Paradigms to Enforce Access Control on Reverse Search Appendix A. Paradigms to Enforce Access Control on Reverse Search
in RDAP . . . . . . . . . . . . . . . . . . . . . . . . . 11 in RDAP . . . . . . . . . . . . . . . . . . . . . . . . . 11
Appendix B. Change Log . . . . . . . . . . . . . . . . . . . . . 12 Appendix B. Change Log . . . . . . . . . . . . . . . . . . . . . 12
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 12 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 13
1. Introduction 1. Introduction
Reverse Whois is a service provided by many web applications that Reverse Whois is a service provided by many web applications that
allow users to find domain names owned by an individual or a company allows users to find domain names owned by an individual or a company
starting from the owner's details, such as name and email. Even if starting from the owner's details, such as name and email. Even if
it has been considered useful for some legal purposes (e.g. it has been considered useful for some legal purposes (e.g.
uncovering trademark infringements, detecting cybercrimes), its uncovering trademark infringements, detecting cybercrimes), its
availability as a standardized Whois capability has been objected to availability as a standardized Whois capability has been objected to
for two main reasons, which now don't seem to conflict with an RDAP for two main reasons, which now don't seem to conflict with an RDAP
implementation. implementation.
The first objection has been caused by the potential risks of privacy The first objection concerns the potential risks of privacy
violation. However, TLDs community is considering a new generation violation. However, the domain name community is considering a new
of Registration Directory Services [ICANN-RDS1] [ICANN-RDS2] generation of Registration Directory Services [ICANN-RDS1]
[ICANN-RA], which provide access to sensitive data under some [ICANN-RDS2] [ICANN-RA], which provide access to sensitive data under
permissible purposes and according to adequate policies to enforce some permissible purposes and in accordance with appropriate policies
the requestor accreditation, authentication, authorization, and terms for requestor accreditation, authentication and authorization.
and conditions of data use. It is well known that such security RDAP's reliance on HTTP means that it can make use of common HTTP-
policies are not implemented in Whois [RFC3912], while they are in based approaches to authentication and authorization, making it more
RDAP [RFC7481]. Therefore, RDAP permits a reverse search useful than Whois [RFC3912] in the context of such directory
implementation complying with privacy protection principles. services. Since RDAP consequently permits a reverse search
implementation complying with privacy protection principles, this
objection is not well-founded.
The other objection to the implementation of a reverse search The other objection to the implementation of a reverse search
capability has been connected with its impact on server processing. capability has been connected with its impact on server processing.
Since RDAP supports search queries, the impact of both standard and However, the core RDAP specifications already define search queries,
reverse searches is equivalent and can be mitigated by servers with similar processing requirements, so the distinction on which
adopting ad hoc strategies. Furthermore, the reverse search is this objection is based is not clear.
almost always performed by specifying an entity role (e.g.
registrant, technical contact) and this can contribute to restricting
the result set.
Reverse searches, such as finding the list of domain names associated Reverse searches, such as finding the list of domain names associated
with contacts or nameservers may be useful to registrars as well. with contacts or nameservers, may be useful to registrars as well.
Usually, registries adopt out-of-band solutions to provide results to Usually, registries adopt out-of-band solutions to provide results to
registrars asking for reverse searches on their domains. Possible registrars asking for reverse searches on their domains. Possible
reasons for such requests are: reasons for such requests are:
* the loss of synchronization between the registrar database and the * the loss of synchronization between the registrar database and the
registry database; registry database;
* the need for such data to perform massive EPP [RFC5730] updates * the need for such data to perform bulk EPP [RFC5730] updates (e.g.
(e.g. changing the contacts of a set of domains, etc.). changing the contacts of a set of domains, etc.).
Currently, RDAP does not provide any means for a client to search for Currently, RDAP does not provide any means for a client to search for
the collection of domains associated with an entity [RFC9082]. A the collection of domains associated with an entity [RFC9082]. A
query (lookup or search) on domains can return the array of entities query (lookup or search) on domains can return the array of entities
related to a domain with different roles (registrant, registrar, related to a domain with different roles (registrant, registrar,
administrative, technical, reseller, etc.), but the reverse operation administrative, technical, reseller, etc.), but the reverse operation
is not allowed. Only reverse searches to find the collection of is not allowed. Only reverse searches to find the collection of
domains related to a nameserver (ldhName or ip) can be requested. domains related to a nameserver (ldhName or ip) can be requested.
Since an entity can be in relationship with any RDAP object Since an entity can be in relationship with any RDAP object
[RFC9083], the availability of a reverse search as largely intended [RFC9083], the availability of a reverse search as largely intended
can be common to all the object classes allowed for search. Through can be common to all the object classes allowed for search. Through
a further step of generalization, the meaning of reverse search in a further step of generalization, the meaning of reverse search in
the RDAP context can be extended to include any query for retrieving the RDAP context can be extended to include any query for retrieving
all the objects in relationship with another matching a given search all the objects in relationship with another matching a given search
pattern. pattern.
The protocol described in this specification aims to extend the RDAP The protocol described in this specification aims to extend the RDAP
query capabilities to enable the reverse search based on the query capabilities to enable reverse search based on the
relationships defined in RDAP between an object class for search and relationships defined in RDAP between an object class for search and
any related object class. The reverse search based on the domain- a related object class. The reverse search based on the domain-
entity relationship is treated as a particular case of such a generic entity relationship is treated as a particular case of such a generic
query model but with a special focus on its privacy implications. query model.
The extension is implemented by adding new path segments (i.e. search
paths) and using a RESTful web service [REST]. The service is
implemented using the Hypertext Transfer Protocol (HTTP) [RFC7230]
and the conventions described in [RFC7480].
1.1. Conventions Used in This Document 1.1. Conventions Used in This Document
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP "OPTIONAL" in this document are to be interpreted as described in BCP
14 [RFC2119] [RFC8174] when, and only when, they appear in all 14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here. capitals, as shown here.
2. RDAP Path Segment Specification 2. RDAP Path Segment Specification
The new search paths are OPTIONAL extensions of those defined in A generic reverse search path is described by the syntax:
[RFC9082]. A generic reverse search path is described by the syntax:
{searchable-resource-type}/reverse/{related-resource-type}?<search- {searchable-resource-type}/reverse_search_0/{related-resource-
condition> type}?<search-condition>
The path segments are defined as in the following: The path segments are defined as in the following:
* searchable-resource-type: it MUST be one of resource types for * searchable-resource-type: it MUST be one of the resource types for
search defined in Section 3.2 of [RFC9082], i.e. "domains", search defined in Section 3.2 of [RFC9082] (i.e. "domains",
"nameservers" and "entities"; "nameservers" and "entities") or a resource type extension;
* related-resource-type: it MUST be one of the resource types for * related-resource-type: it MUST be one of the resource types for
lookup defined in Section 3.1 of [RFC9082], i.e. "domain", lookup defined in Section 3.1 of [RFC9082] (i.e. "domain",
"nameserver", "entity", "ip" and "autnum"; "nameserver", "entity", "ip" and "autnum") or a resource type
extension;
* search-condition: a sequence of "property=search pattern" * search-condition: a sequence of "property=search pattern"
predicates separated by the ampersand character ('&', US-ASCII predicates separated by the ampersand character ('&', US-ASCII
value 0x0026). Each "property" represents a JSON object property value 0x0026). Each "property" represents a JSON object property
of the RDAP object class corresponding to "related-resource-type". of the RDAP object class corresponding to "related-resource-type".
All the predicates are joined by the AND logical operator. Based Objects are only included in the search results if they satisfy
on their policy, servers MAY restrict the usage of predicates to all included predicates. This includes predicates that are for
make a valid search condition. the same property: it is necessary in such a case for the related
object to match against each of those predicates. Based on their
policy, servers MAY restrict the usage of predicates to make a
valid search condition, by returning a 400 (Bad Request) response
when a problematic request is received.
While related-resource-type is defined as having one of a number of
different values, the only searches defined in this document are for
a related-resource-type of "entity". Searches for the other resource
types specified in [RFC9082] and resource type extensions may be
defined by future documents.
Partial string matching in search patterns is allowed as defined in Partial string matching in search patterns is allowed as defined in
section 4.1 of [RFC9082]. section 4.1 of [RFC9082].
2.1. Reverse Searches Based on Entity Details 3. RDAP Response Specification
Reverse search responses use the formats defined in section 8 of
[RFC9083], which correspond to the searchable resource types defined
in Section 2.
4. Reverse Searches Based on Entity Details
Since in RDAP, an entity can be associated with any other object Since in RDAP, an entity can be associated with any other object
class, the most common kind of reverse searches are based on the class, the most common kind of reverse search is one based on an
entity details. Such reverse searches arise from the above query entity's details. Such reverse searches arise from the query model
model by setting the related resource type to "entity". by setting the related resource type to "entity".
By selecting a specific searchable resource type, the resulting By selecting a specific searchable resource type, the resulting
reverse search aims at retrieving all the objects (e.g. all the reverse search aims at retrieving all the objects (e.g. all the
domains) that are related to any entity object matching the search domains) that are related to any entity object matching the search
condition. conditions.
This section defines the following reverse search properties to be This section defines the following reverse search properties servers
used regardless of the searchable resource type being selected: SHOULD support regardless of the searchable resource type being
selected:
Reverse search property: role Reverse search property: role
RDAP property: $..entities[*].roles RDAP property: $..entities[*].roles
Reference: Section 10.2.4 of [RFC9083] Reference: Section 10.2.4 of [RFC9083]
Reverse search property: handle Reverse search property: handle
RDAP property: $..entities[*].handle RDAP property: $..entities[*].handle
Reference: Section 5.1 of [RFC9083] Reference: Section 5.1 of [RFC9083]
Reverse search property: fn Reverse search property: fn
Using jCard:
RDAP property: $..entities[*].vcardArray[1][?(@[0]=='fn')][3] RDAP property: $..entities[*].vcardArray[1][?(@[0]=='fn')][3]
Reference: Section 6.2.1 of [RFC6350] Reference: Section 6.2.1 of [RFC6350]
Using JSContact:
RDAP property: $..entities[*].jscard.fullName
Reference: Section 2.2.2 of [I-D.ietf-calext-jscontact]
Reverse search property: email Reverse search property: email
Using jCard:
RDAP property: $..entities[*].vcardArray[1][?(@[0]=='email')][3] RDAP property: $..entities[*].vcardArray[1][?(@[0]=='email')][3]
Reference: Section 6.4.2 of [RFC6350] Reference: Section 6.4.2 of [RFC6350]
Using JSContact:
RDAP property: $..entities[*].jscard.emails.[*].email
Reference: Section 2.3.1 of [I-D.ietf-calext-jscontact]
Regarding the above definitions, it must be noted that: The mapping between the reverse search property and the corresponding
RDAP response property is done through the use of a JSONPath
expression [I-D.ietf-jsonpath-base].
* the mapping between the reverse search property and the The presence of a predicate on the reverse search property "role"
corresponding RDAP response property is done through the use of a means that the RDAP response property "roles" must contain at least
JSONPath expression [I-D.ietf-jsonpath-base]; the specified role.
* the presence of a predicate on the reverse search property "role"
means that the RDAP response property "roles" must contain at
least the specified role;
* the last two properties are related to jCard elements [RFC7095]
but, being jCard the JSON format for vCard, the corresponding
reference is to the vCard specification [RFC6350]. Such
properties are also shown according to the JSContact format
[I-D.ietf-calext-jscontact] to address the case when it is used
instead of jCard as described in [I-D.ietf-regext-rdap-jscontact].
Servers MAY implement other properties than those defined in this The last two properties are related to jCard elements [RFC7095], but
section. the field references are to vCard [RFC6350], since jCard is the JSON
format for vCard.
Examples of reverse search paths based on the domain-entity Examples of reverse search paths based on the domain-entity
relationship are presented below: relationship are presented in Figure 1.
/domains/reverse/entity?handle=CID-40*&role=technical /domains/reverse_search_0/entity?handle=CID-40*&role=technical
/domains/reverse/entity?fn=Bobby*&role=registrant /domains/reverse_search_0/entity?fn=Bobby*&role=registrant
/domains/reverse/entity?handle=RegistrarX&role=registrar /domains/reverse_search_0/entity?handle=RegistrarX&role=registrar
Figure 1 Figure 1
3. RDAP Conformance Documents that deprecate or restructure RDAP responses such that one
or more of the properties listed above becomes invalid MUST either
note that the relevant reverse search is no longer available (in the
case of deprecation) or describe how to continue supporting the
relevant search by way of some new RDAP property (in the case of
restructuring).
A server that includes additional fields in its objects in accordance
with the extensibility provisions of section 6 of [RFC7480] MAY
support the use of those fields in search conditions, in the same way
as for the search conditions defined in this section. Support for
such fields in the reverse search context MUST be documented in the
extension specification.
5. RDAP Conformance
Servers complying with this specification MUST include the value Servers complying with this specification MUST include the value
"reverse_search_0" in the rdapConformance property of the help "reverse_search_0" in the rdapConformance property of the help
response [RFC9083]. The information needed to register this value in response [RFC9083]. The information needed to register this value in
the "RDAP Extensions" registry is described in Section 6. the "RDAP Extensions" registry is described in Section 8.
4. Implementation Considerations 6. Implementation Considerations
The implementation of the proposed extension is technically feasible.
To limit the impact of processing the search predicates, servers are To limit the impact of processing the search predicates, servers are
RECOMMENDED to mandate the use of at least one property among those RECOMMENDED to make use of indexes and similar functionality in their
mapped to indexed fields of the registry database. Other properties, underlying data store. In addition, risks with respect to
such as "role", MAY be allowed to further restrict the set of performance degradation or result set generation can be mitigated by
possible results. In addition, the risks to degrade the performance adopting practices used for standard searches, e.g. restricting the
or to generate huge result sets can be mitigated by adopting the same search functionality, limiting the rate of search requests according
policies valid for handling searches (e.g. restricting the search to the user's authorization, truncating and paging the results, and
functionality, limiting the rate of search requests according to the returning partial responses.
user profile, truncating and paging the results, returning partial
responses).
5. Implementation Status 7. Implementation Status
NOTE: Please remove this section and the reference to RFC 7942 prior NOTE: Please remove this section and the reference to RFC 7942 prior
to publication as an RFC. to publication as an RFC.
This section records the status of known implementations of the This section records the status of known implementations of the
protocol defined by this specification at the time of posting of this protocol defined by this specification at the time of posting of this
Internet-Draft, and is based on a proposal described in [RFC7942]. Internet-Draft, and is based on a proposal described in [RFC7942].
The description of implementations in this section is intended to The description of implementations in this section is intended to
assist the IETF in its decision processes in progressing drafts to assist the IETF in its decision processes in progressing drafts to
RFCs. Please note that the listing of any individual implementation RFCs. Please note that the listing of any individual implementation
skipping to change at page 7, line 16 skipping to change at page 7, line 30
features. Readers are advised to note that other implementations may features. Readers are advised to note that other implementations may
exist. exist.
According to RFC 7942, "this will allow reviewers and working groups According to RFC 7942, "this will allow reviewers and working groups
to assign due consideration to documents that have the benefit of to assign due consideration to documents that have the benefit of
running code, which may serve as evidence of valuable experimentation running code, which may serve as evidence of valuable experimentation
and feedback that have made the implemented protocols more mature. and feedback that have made the implemented protocols more mature.
It is up to the individual working groups to use this information as It is up to the individual working groups to use this information as
they see fit". they see fit".
5.1. IIT-CNR/Registro.it RDAP Server 7.1. IIT-CNR/Registro.it RDAP Server
* Responsible Organization: Institute of Informatics and Telematics * Responsible Organization: Institute of Informatics and Telematics
of National Research Council (IIT-CNR)/Registro.it of National Research Council (IIT-CNR)/Registro.it
* Location: https://rdap.pubtest.nic.it/ * Location: https://rdap.pubtest.nic.it/
* Description: This implementation includes support for RDAP queries * Description: This implementation includes support for RDAP queries
using data from the public test environment of .it ccTLD. Reverse using data from the public test environment of .it ccTLD. Reverse
search is allowed to authenticated users. Registrar users are search is allowed to authenticated users. Registrar users are
allowed to perform reverse searches on their own domains and allowed to perform reverse searches on their own domains and
contacts. This is achieved by adding an implicit condition to the contacts. This is achieved by adding an implicit predicate to the
search pattern. search condition.
* Level of Maturity: This is an "alpha" test implementation. * Level of Maturity: This is an "alpha" test implementation.
* Coverage: This implementation includes all of the features * Coverage: This implementation includes all of the features
described in this specification. described in this specification.
* Contact Information: Mario Loffredo, mario.loffredo@iit.cnr.it * Contact Information: Mario Loffredo, mario.loffredo@iit.cnr.it
5.2. IIT-CNR/Registro.it RDAP Client 7.2. IIT-CNR/Registro.it RDAP Client
* Responsible Organization: Institute of Informatics and Telematics * Responsible Organization: Institute of Informatics and Telematics
of National Research Council (IIT-CNR)/Registro.it of National Research Council (IIT-CNR)/Registro.it
* Location: https://web-rdap.pubtest.nic.it/ * Location: https://web-rdap.pubtest.nic.it/
* Description: This is a Javascript web-based RDAP client. RDAP * Description: This is a Javascript web-based RDAP client. RDAP
responses are retrieved from RDAP servers by the browser, parsed responses are retrieved from RDAP servers by the browser, parsed
into an HTML representation, and displayed in a format improving into an HTML representation, and displayed in a format improving
the user experience. Reverse search is allowed to authenticated the user experience. Reverse search is allowed to authenticated
users. users.
* Level of Maturity: This is an "alpha" test implementation. * Level of Maturity: This is an "alpha" test implementation.
* Coverage: This implementation includes all of the features * Coverage: This implementation includes all of the features
described in this specification. described in this specification.
* Contact Information: Francesco Donini, francesco.donini@iit.cnr.it * Contact Information: Francesco Donini, francesco.donini@iit.cnr.it
6. IANA Considerations 8. IANA Considerations
IANA is requested to register the following value in the RDAP IANA is requested to register the following value in the RDAP
Extensions Registry: Extensions Registry:
* Extension identifier: reverse_search_0 * Extension identifier: reverse_search_0
* Registry operator: Any * Registry operator: Any
* Published specification: This document. * Published specification: This document.
* Contact: IETF <iesg@ietf.org> * Contact: IETF <iesg@ietf.org>
* Intended usage: This extension describes reverse search query * Intended usage: This extension describes reverse search query
patterns for RDAP. patterns for RDAP.
7. Privacy Considerations 9. Privacy Considerations
The use of the capability described in this document whenever a The search functionality defined in this document may affect the
contact detail is taken MUST be compliant with the rules about privacy of entities in the registry (and elsewhere) in various ways:
privacy protection each RDAP provider is subject to. Sensitive see [RFC6973] for a general treatment of privacy in protocol
registration data MUST be protected and accessible for permissible specifications. Registry operators should be aware of the tradeoffs
purposes only. This feature SHOULD be only accessible to authorized that result from implementation of this functionality.
users and only for a specified use case.
Since the request for this feature could contain Personal Many jurisdictions have laws or regulations that restrict the use of
Identifiable Information, it SHOULD only be accessible to authorized "Personal Data", per the definition in [RFC6973]. Given that,
users and available over HTTPS. registry operators should ascertain whether the regulatory
environment in which they operate permits implementation of the
functionality defined in this document.
In general, given the sensitivity of this functionality,it SHOULD be
accessible to authorized users only, and for specific use cases only.
Since reverse search requests and responses could contain Personally
Identifiable Information (PII), reverse search functionality SHOULD
be available over HTTPS only.
Providing reverse search in RDAP carries the following threats as Providing reverse search in RDAP carries the following threats as
described in [RFC6973]: described in [RFC6973]:
* Correlation * Correlation
* Disclosure * Disclosure
* Misuse of information * Misuse of information
Therefore, RDAP providers are REQUIRED to mitigate the risk of those Therefore, RDAP providers are REQUIRED to mitigate the risk of those
threats by implementing appropriate measures supported by security threats by implementing appropriate measures supported by security
services (see Section 8). services (see Section 10).
8. Security Considerations 10. Security Considerations
Security services required to provide controlled access to the Security services required to provide controlled access to the
operations specified in this document are described in [RFC7481]. A operations specified in this document are described in [RFC7481]. A
non-exhaustive list of access control paradigms an RDAP provider can non-exhaustive list of access control paradigms an RDAP provider can
implement is presented in Appendix A. implement is presented in Appendix A.
The specification of the relationship within the reverse search path The specification of the relationship within the reverse search path
allows the RDAP servers to implement different authorization policies allows the RDAP servers to implement different authorization policies
on a per-relationship basis. on a per-relationship basis.
9. Acknowledgements 11. Acknowledgements
The authors would like to acknowledge the following individuals for The authors would like to acknowledge the following individuals for
their contributions to this document: Francesco Donini, Scott their contributions to this document: Francesco Donini, Scott
Hollenbeck, Francisco Arias, Gustavo Lozano, Eduardo Alvarez and Hollenbeck, Francisco Arias, Gustavo Lozano, Eduardo Alvarez, Ulrich
Ulrich Wisser. Wisser and James Gould.
Tom Harrison and Jasdip Singh provided relevant feedback and constant Tom Harrison and Jasdip Singh provided relevant feedback and constant
support to the implementation of this proposal. Their contributions support to the implementation of this proposal. Their contributions
are greatly appreciated. have been greatly appreciated.
10. References 12. References
10.1. Normative References 12.1. Normative References
[OIDCC] OpenID Foundation, "OpenID Connect Core incorporating [OIDCC] OpenID Foundation, "OpenID Connect Core incorporating
errata set 1", November 2014, errata set 1", November 2014,
<http://openid.net/specs/openid-connect-core-1_0.html>. <http://openid.net/specs/openid-connect-core-1_0.html>.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997, DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>. <https://www.rfc-editor.org/info/rfc2119>.
skipping to change at page 9, line 44 skipping to change at page 10, line 19
[RFC6973] Cooper, A., Tschofenig, H., Aboba, B., Peterson, J., [RFC6973] Cooper, A., Tschofenig, H., Aboba, B., Peterson, J.,
Morris, J., Hansen, M., and R. Smith, "Privacy Morris, J., Hansen, M., and R. Smith, "Privacy
Considerations for Internet Protocols", RFC 6973, Considerations for Internet Protocols", RFC 6973,
DOI 10.17487/RFC6973, July 2013, DOI 10.17487/RFC6973, July 2013,
<https://www.rfc-editor.org/info/rfc6973>. <https://www.rfc-editor.org/info/rfc6973>.
[RFC7095] Kewisch, P., "jCard: The JSON Format for vCard", RFC 7095, [RFC7095] Kewisch, P., "jCard: The JSON Format for vCard", RFC 7095,
DOI 10.17487/RFC7095, January 2014, DOI 10.17487/RFC7095, January 2014,
<https://www.rfc-editor.org/info/rfc7095>. <https://www.rfc-editor.org/info/rfc7095>.
[RFC7230] Fielding, R., Ed. and J. Reschke, Ed., "Hypertext Transfer
Protocol (HTTP/1.1): Message Syntax and Routing",
RFC 7230, DOI 10.17487/RFC7230, June 2014,
<https://www.rfc-editor.org/info/rfc7230>.
[RFC7480] Newton, A., Ellacott, B., and N. Kong, "HTTP Usage in the [RFC7480] Newton, A., Ellacott, B., and N. Kong, "HTTP Usage in the
Registration Data Access Protocol (RDAP)", STD 95, Registration Data Access Protocol (RDAP)", STD 95,
RFC 7480, DOI 10.17487/RFC7480, March 2015, RFC 7480, DOI 10.17487/RFC7480, March 2015,
<https://www.rfc-editor.org/info/rfc7480>. <https://www.rfc-editor.org/info/rfc7480>.
[RFC7481] Hollenbeck, S. and N. Kong, "Security Services for the [RFC7481] Hollenbeck, S. and N. Kong, "Security Services for the
Registration Data Access Protocol (RDAP)", STD 95, Registration Data Access Protocol (RDAP)", STD 95,
RFC 7481, DOI 10.17487/RFC7481, March 2015, RFC 7481, DOI 10.17487/RFC7481, March 2015,
<https://www.rfc-editor.org/info/rfc7481>. <https://www.rfc-editor.org/info/rfc7481>.
skipping to change at page 10, line 29 skipping to change at page 10, line 48
[RFC9082] Hollenbeck, S. and A. Newton, "Registration Data Access [RFC9082] Hollenbeck, S. and A. Newton, "Registration Data Access
Protocol (RDAP) Query Format", STD 95, RFC 9082, Protocol (RDAP) Query Format", STD 95, RFC 9082,
DOI 10.17487/RFC9082, June 2021, DOI 10.17487/RFC9082, June 2021,
<https://www.rfc-editor.org/info/rfc9082>. <https://www.rfc-editor.org/info/rfc9082>.
[RFC9083] Hollenbeck, S. and A. Newton, "JSON Responses for the [RFC9083] Hollenbeck, S. and A. Newton, "JSON Responses for the
Registration Data Access Protocol (RDAP)", STD 95, Registration Data Access Protocol (RDAP)", STD 95,
RFC 9083, DOI 10.17487/RFC9083, June 2021, RFC 9083, DOI 10.17487/RFC9083, June 2021,
<https://www.rfc-editor.org/info/rfc9083>. <https://www.rfc-editor.org/info/rfc9083>.
10.2. Informative References 12.2. Informative References
[I-D.ietf-calext-jscontact]
Stepanek, R. and M. Loffredo, "JSContact: A JSON
representation of contact data", Work in Progress,
Internet-Draft, draft-ietf-calext-jscontact-00, 17 January
2020, <https://www.ietf.org/archive/id/draft-ietf-calext-
jscontact-00.txt>.
[I-D.ietf-jsonpath-base] [I-D.ietf-jsonpath-base]
Gössner, S., Normington, G., and C. Bormann, "JSONPath: Gössner, S., Normington, G., and C. Bormann, "JSONPath:
Query expressions for JSON", Work in Progress, Internet- Query expressions for JSON", Work in Progress, Internet-
Draft, draft-ietf-jsonpath-base-03, 16 January 2022, Draft, draft-ietf-jsonpath-base-03, 16 January 2022,
<https://www.ietf.org/archive/id/draft-ietf-jsonpath-base- <https://www.ietf.org/archive/id/draft-ietf-jsonpath-base-
03.txt>. 03.txt>.
[I-D.ietf-regext-rdap-jscontact]
Loffredo, M. and G. Brown, "Using JSContact in
Registration Data Access Protocol (RDAP) JSON Responses",
Work in Progress, Internet-Draft, draft-ietf-regext-rdap-
jscontact-09, 7 March 2022,
<https://www.ietf.org/archive/id/draft-ietf-regext-rdap-
jscontact-09.txt>.
[I-D.ietf-regext-rdap-openid] [I-D.ietf-regext-rdap-openid]
Hollenbeck, S., "Federated Authentication for the Hollenbeck, S., "Federated Authentication for the
Registration Data Access Protocol (RDAP) using OpenID Registration Data Access Protocol (RDAP) using OpenID
Connect", Work in Progress, Internet-Draft, draft-ietf- Connect", Work in Progress, Internet-Draft, draft-ietf-
regext-rdap-openid-08, 8 November 2021, regext-rdap-openid-08, 8 November 2021,
<https://www.ietf.org/archive/id/draft-ietf-regext-rdap- <https://www.ietf.org/archive/id/draft-ietf-regext-rdap-
openid-08.txt>. openid-08.txt>.
[ICANN-RA] Internet Corporation For Assigned Names and Numbers, [ICANN-RA] Internet Corporation For Assigned Names and Numbers,
"Registry Agreement", July 2017, "Registry Agreement", July 2017,
skipping to change at page 11, line 33 skipping to change at page 11, line 36
<https://www.icann.org/en/system/files/files/final-report- <https://www.icann.org/en/system/files/files/final-report-
06jun14-en.pdf>. 06jun14-en.pdf>.
[ICANN-RDS2] [ICANN-RDS2]
Internet Corporation For Assigned Names and Numbers, Internet Corporation For Assigned Names and Numbers,
"Final Issue Report on a Next-Generation gTLD RDS to "Final Issue Report on a Next-Generation gTLD RDS to
Replace WHOIS", October 2015, Replace WHOIS", October 2015,
<http://whois.icann.org/sites/default/files/files/final- <http://whois.icann.org/sites/default/files/files/final-
issue-report-next-generation-rds-07oct15-en.pdf>. issue-report-next-generation-rds-07oct15-en.pdf>.
[REST] Fielding, R., "Architectural Styles and the Design of
Network-based Software Architectures", 2000,
<http://www.ics.uci.edu/~fielding/pubs/dissertation/
fielding_dissertation.pdf>.
Appendix A. Paradigms to Enforce Access Control on Reverse Search in Appendix A. Paradigms to Enforce Access Control on Reverse Search in
RDAP RDAP
Access control can be implemented according to different paradigms Access control can be implemented according to different paradigms
introducing increasingly stringent rules. The paradigms reported introducing increasingly stringent rules. The paradigms reported
here in the following leverage the capabilities either supported here in the following leverage the capabilities either supported
natively or provided as extensions by the OpenID Connect [OIDCC]: natively or provided as extensions by the OpenID Connect [OIDCC]:
* Role-Based Access Control: access rights are granted depending on * Role-Based Access Control: access rights are granted depending on
roles. Generally, this is done by grouping users into fixed roles. Generally, this is done by grouping users into fixed
categories and assigning each category with static grants. A more categories and assigning static grants to each category. A more
dynamic approach can be implemented by using the OpenID Connect dynamic approach can be implemented by using the OpenID Connect
"scope" claim; "scope" claim;
* Purpose-Based Access Control: access rules are based on the notion * Purpose-Based Access Control: access rules are based on the notion
of purpose which means the intended usage of some data by a user. of purpose, being the intended use of some data by a user. It can
It can be implemented by tagging a request with the usage purpose be implemented by tagging a request with the usage purpose and
and making the RDAP server check the compliance between the given making the RDAP server check the compliance between the given
purpose and the control rules applied to data to be returned. The purpose and the control rules applied to the data to be returned.
purpose can be stated within an out-of-band process by setting the The purpose can be stated within an out-of-band process by setting
OpenID Connect RDAP specific "purpose" claim as defined in the OpenID Connect RDAP-specific "purpose" claim as defined in
[I-D.ietf-regext-rdap-openid]; [I-D.ietf-regext-rdap-openid];
* Attribute-Based Access Control: rules to manage access rights are * Attribute-Based Access Control: rules to manage access rights are
evaluated and applied according to specific attributes describing evaluated and applied according to specific attributes describing
the context within which data are requested. It can be the context within which data are requested. It can be
implemented by setting within an out-of-band process additional implemented by setting within an out-of-band process additional
OpenID Connect claims describing the request context and making OpenID Connect claims describing the request context and making
the RDAP server check the compliance between the given context and the RDAP server check the compliance between the given context and
the control rules applied to data to be returned; the control rules applied to the data to be returned;
* Time-Based Access Control: data access is allowed for a limited * Time-Based Access Control: data access is allowed for a limited
time only. It can be implemented by assigning the users with time only. It can be implemented by assigning the users with
temporary credentials linked to access grants whose scope is temporary credentials linked to access grants whose scope is
limited. limited.
Appendix B. Change Log Appendix B. Change Log
00: Initial working group version ported from draft-loffredo-regext- 00: Initial working group version ported from draft-loffredo-regext-
rdap-reverse-search-04 rdap-reverse-search-04
01: Updated "Privacy Considerations" section. 01: Updated "Privacy Considerations" section.
skipping to change at page 12, line 49 skipping to change at page 12, line 45
references. Added Appendix A. references. Added Appendix A.
07: Updated normative references. 07: Updated normative references.
08: Changed "Implementation Status" section. Updated informative 08: Changed "Implementation Status" section. Updated informative
references. references.
09: Extended the query model to represent a reverse search based on 09: Extended the query model to represent a reverse search based on
any relationship between the RDAP object classes. Changed the any relationship between the RDAP object classes. Changed the
path segment "role" into a query parameter. path segment "role" into a query parameter.
10: Updated "Reverse Searches Based on Entity Details" section to 10: Updated "Reverse Searches Based on Entity Details" section to
consider the use of JSContact format instead of jCard. Added consider the use of JSContact format instead of jCard. Added
references to JSContact documents. references to JSContact documents.
11: Updated the document based on Tom Harrison and James Gould
feedback:
* Updated section "RDAP Path Segment Specification":
- Clarified how servers must evaluate a reverse search
including predicates that are for the same property.
- Specified the error response servers must return when
receiving a wrong reverse search request according to their
policy.
- Clarified that searchs for the related-resource-type values
other than "entity" may be defined in future documents.
* Reviewed text in section "Reverse Searches Based on Entity
Details" about reverse searches based on custom response
extensions.
* Removed references to JSContact documents in section "Reverse
Searches Based on Entity Details". Moved the mapping between
jCard properties used in the RDAP response and JSContact
counterparts to draft-ietf-regext-rdap-jscontact.
* Added section "RDAP Response Specification".
* Changed the text to present reverse search as a single
extension with multiple features.
* Changed the definition of searchable-resource-type and related-
resource-type to consider also the resource type extensions.
* Replaced "reverse" with "reverse_search_0" in the generic
reverse search path. Updated Figure 1 accordingly.
* Removed the phrase "but with a special focus on its privacy
implications" from both the "Abstract" and the "Introduction".
Moved the mapping between jCard properties used in the RDAP
response and JSContact counterparts to draft-ietf-regext-rdap-
jscontact.
* Reviewed the text of "Privacy Considerations" section.
* Text cleaning.
Authors' Addresses Authors' Addresses
Mario Loffredo Mario Loffredo
IIT-CNR/Registro.it IIT-CNR/Registro.it
Via Moruzzi,1 Via Moruzzi,1
56124 Pisa 56124 Pisa
Italy Italy
Email: mario.loffredo@iit.cnr.it Email: mario.loffredo@iit.cnr.it
URI: http://www.iit.cnr.it URI: http://www.iit.cnr.it
Maurizio Martinelli Maurizio Martinelli
IIT-CNR/Registro.it IIT-CNR/Registro.it
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