Internet DRAFT - draft-ietf-regext-secure-authinfo-transfer
draft-ietf-regext-secure-authinfo-transfer
Network Working Group J. Gould
Internet-Draft R. Wilhelm
Intended status: Standards Track VeriSign, Inc.
Expires: 30 December 2021 28 June 2021
Extensible Provisioning Protocol (EPP) Secure Authorization Information
for Transfer
draft-ietf-regext-secure-authinfo-transfer-07
Abstract
The Extensible Provisioning Protocol (EPP), in RFC 5730, defines the
use of authorization information to authorize a transfer of an EPP
object, such as a domain name, between clients that are referred to
as registrars. Object-specific, password-based authorization
information (see RFC 5731 and RFC 5733) is commonly used, but raises
issues related to the security, complexity, storage, and lifetime of
authentication information. This document defines an operational
practice, using the EPP RFCs, that leverages the use of strong random
authorization information values that are short-lived, not stored by
the client, and stored by the server using a cryptographic hash that
provides for secure authorization information that can safely be used
for object transfers.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
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Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
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material or to cite them other than as "work in progress."
This Internet-Draft will expire on 30 December 2021.
Copyright Notice
Copyright (c) 2021 IETF Trust and the persons identified as the
document authors. All rights reserved.
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This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents (https://trustee.ietf.org/
license-info) in effect on the date of publication of this document.
Please review these documents carefully, as they describe your rights
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Conventions Used in This Document . . . . . . . . . . . . 4
2. Registrant, Registrar, Registry . . . . . . . . . . . . . . . 5
3. Signaling Client and Server Support . . . . . . . . . . . . . 6
4. Secure Authorization Information . . . . . . . . . . . . . . 7
4.1. Secure Random Authorization Information . . . . . . . . . 7
4.2. Authorization Information Time-To-Live (TTL) . . . . . . 8
4.3. Authorization Information Storage and Transport . . . . . 8
4.4. Authorization Information Matching . . . . . . . . . . . 9
5. Create, Transfer, and Secure Authorization Information . . . 10
5.1. Create Command . . . . . . . . . . . . . . . . . . . . . 10
5.2. Update Command . . . . . . . . . . . . . . . . . . . . . 12
5.3. Info Command and Response . . . . . . . . . . . . . . . . 15
5.4. Transfer Request Command . . . . . . . . . . . . . . . . 17
6. Transition Considerations . . . . . . . . . . . . . . . . . . 18
6.1. Transition Phase 1 - Features . . . . . . . . . . . . . . 20
6.2. Transition Phase 2 - Storage . . . . . . . . . . . . . . 21
6.3. Transition Phase 3 - Enforcement . . . . . . . . . . . . 21
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 21
7.1. XML Namespace . . . . . . . . . . . . . . . . . . . . . . 21
7.2. EPP Extension Registry . . . . . . . . . . . . . . . . . 22
8. Implementation Status . . . . . . . . . . . . . . . . . . . . 22
8.1. Verisign EPP SDK . . . . . . . . . . . . . . . . . . . . 23
8.2. RegistryEngine EPP Service . . . . . . . . . . . . . . . 23
9. Security Considerations . . . . . . . . . . . . . . . . . . . 24
10. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 24
11. References . . . . . . . . . . . . . . . . . . . . . . . . . 24
11.1. Normative References . . . . . . . . . . . . . . . . . . 24
11.2. Informative References . . . . . . . . . . . . . . . . . 25
Appendix A. Change History . . . . . . . . . . . . . . . . . . . 26
A.1. Change from 00 to 01 . . . . . . . . . . . . . . . . . . 26
A.2. Change from 01 to 02 . . . . . . . . . . . . . . . . . . 26
A.3. Change from 02 to 03 . . . . . . . . . . . . . . . . . . 26
A.4. Change from 03 to REGEXT 00 . . . . . . . . . . . . . . . 28
A.5. Change from REGEXT 00 to REGEXT 01 . . . . . . . . . . . 28
A.6. Change from REGEXT 01 to REGEXT 02 . . . . . . . . . . . 28
A.7. Change from REGEXT 02 to REGEXT 03 . . . . . . . . . . . 28
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A.8. Change from REGEXT 03 to REGEXT 04 . . . . . . . . . . . 28
A.9. Change from REGEXT 04 to REGEXT 05 . . . . . . . . . . . 28
A.10. Change from REGEXT 05 to REGEXT 06 . . . . . . . . . . . 29
A.11. Change from REGEXT 06 to REGEXT 07 . . . . . . . . . . . 29
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 31
1. Introduction
The Extensible Provisioning Protocol (EPP), in [RFC5730], defines the
use of authorization information to authorize a transfer of an EPP
object, such as a domain name, between clients that are referred to
as registrars. The authorization information is object-specific and
has been defined in the EPP Domain Name Mapping, in [RFC5731], and
the EPP Contact Mapping, in [RFC5733], as password-based
authorization information. Other authorization mechanisms can be
used, but in practice the password-based authorization information
has been used at the time of object create, managed with the object
update, and used to authorize an object transfer request. What has
not been considered is the security of the authorization information
that includes the complexity of the authorization information, the
time-to-live (TTL) of the authorization information, and where and
how the authorization information is stored.
The current/original lifecycle for authorization information involves
long-term storage of encrypted (not hashed) passwords, which presents
a significant latent risk of password compromise and is not
consistent with current best practices. The mechanisms in this
document provide a way to avoid long-term password storage entirely,
and to only require the storage of hashed (not retrievable) passwords
instead of encrypted passwords.
This document defines an operational practice, using the EPP RFCs,
that leverages the use of strong, random authorization information
values that are short-lived, that are not stored by the client, and
that are stored by the server using a cryptographic hash to provide
secure authorization information used for transfers. This
operational practice can be used to support transfers of any EPP
object, where the domain name object defined in [RFC5731] is used in
this document for illustration purposes. Elements of the practice
may be used to support the secure use of the authorization
information for purposes other than transfer, but any other purposes
and the applicable elements are out-of-scope for this document.
The overall goal is to have strong, random authorization information
values, that are short-lived, and that are either not stored or
stored as a cryptographic hash values by the non-responsible parties.
In a registrant, registrar, and registry model, the registrant
registers the object through the registrar to the registry. The
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registrant is the responsible party and the registrar and the
registry are the non-responsible parties. EPP is a protocol between
the registrar and the registry, where the registrar is referred to as
the client and the registry is referred to as the server. The
following are the elements of the operational practice and how the
existing features of the EPP RFCs can be leveraged to satisfy them:
"Strong Random Authorization Information": The EPP RFCs define the
password-based authorization information value using an XML
schema "normalizedString" type, so they don't restrict what can
be used in any substantial way. This operational practice
defines the recommended mechanism for creating a strong random
authorization value, that would be generated by the client.
"Short-Lived Authorization Information": The EPP RFCs don't
explicitly support short-lived authorization information or a
time-to-live (TTL) for authorization information, but there are
EPP RFC features that can be leveraged to support short-lived
authorization information. All of these features are compatible
with the EPP RFCs, though not mandatory to implement. In section
2.6 of [RFC5731] it states that authorization information is
assigned when a domain object is created, which results in long-
lived authorization information. This specification changes the
nature of the authorization information to be short-lived. If
authorization information is set only when there is a transfer in
process, the server needs to support an empty authorization
information value on create, support setting and unsetting
authorization information, and support automatically unsetting
the authorization information upon a successful transfer. All of
these features can be supported by the EPP RFCs.
"Storing Authorization Information Securely": The EPP RFCs don't
specify where and how the authorization information is stored in
the client or the server, so there are no restrictions to define
an operational practice for storing the authorization information
securely. The operational practice will require the client to
not store the authorization information and will require the
server to store the authorization information using a
cryptographic hash, with at least a 256-bit hash function, such
as SHA-256 [FIPS-180-4], and with a per-authorization information
random salt, with at least 128 bits. Returning the authorization
information set in an EPP info response will not be supported.
1.1. Conventions Used in This Document
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP
14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
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XML is case sensitive. Unless stated otherwise, XML specifications
and examples provided in this document MUST be interpreted in the
character case presented in order to develop a conforming
implementation.
In examples, "C:" represents lines sent by a protocol client and "S:"
represents lines returned by a protocol server. Indentation and
white space in examples are provided only to illustrate element
relationships and are not a required feature of this protocol.
The examples reference XML namespace prefixes that are used for the
associated XML namespaces. Implementations MUST NOT depend on the
example XML namespaces and instead employ a proper namespace-aware
XML parser and serializer to interpret and output the XML documents.
The example namespace prefixes used and their associated XML
namespaces include:
"domain": urn:ietf:params:xml:ns:domain-1.0
"contact": urn:ietf:params:xml:ns:contact-1.0
2. Registrant, Registrar, Registry
The EPP RFCs refer to client and server, but when it comes to
transfers, there are three types of actors that are involved. This
document will refer to the actors as registrant, registrar, and
registry. [RFC8499] defines these terms formally for the Domain Name
System (DNS). The terms are further described below to cover their
roles as actors of using the authorization information in the
transfer process of any object in the registry, such as a domain name
or a contact:
"registrant": [RFC8499] defines the registrant as "an individual or
organization on whose behalf a name in a zone is registered by
the registry". The registrant can be the owner of any object in
the registry, such as a domain name or a contact. The registrant
interfaces with the registrar for provisioning the objects. A
transfer is coordinated by the registrant to transfer the
sponsorship of the object from one registrar to another. The
authorization information is meant to authenticate the registrant
as the owner of the object to the non-sponsoring registrar and to
authorize the transfer.
"registrar": [RFC8499] defines the registrar as "a service provider
that acts as a go-between for registrants and registries". The
registrar interfaces with the registrant for the provisioning of
objects, such as domain names and contacts, and with the
registries to satisfy the registrant's provisioning requests. A
registrar may directly interface with the registrant or may
indirectly interface with the registrant, typically through one
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or more resellers. Implementing a transfer using secure
authorization information extends through the registrar's
reseller channel up to the direct interface with the registrant.
The registrar's interface with the registries uses EPP. The
registrar's interface with its reseller channel or the registrant
is registrar-specific. In the EPP RFCs, the registrar is
referred to as the "client", since EPP is the protocol used
between the registrar and the registry. The sponsoring registrar
is the authorized registrar to manage objects on behalf of the
registrant. A non-sponsoring registrar is not authorized to
manage objects on behalf of the registrant. A transfer of an
object's sponsorship is from one registrar, referred to as the
losing registrar, to another registrar, referred to as the
gaining registrar.
"registry": [RFC8499] defines the registry as "the administrative
operation of a zone that allows registration of names within the
zone". The registry typically interfaces with the registrars
over EPP and generally does not interact directly with the
registrant. In the EPP RFCs, the registry is referred to as the
"server", since EPP is the protocol used between the registrar
and the registry. The registry has a record of the sponsoring
registrar for each object and provides the mechanism (over EPP)
to coordinate a transfer of an object's sponsorship between
registrars.
3. Signaling Client and Server Support
This document does not define new protocol but an operational
practice using the existing EPP protocol, where the client and the
server can signal support for the operational practice using a
namespace URI in the login and greeting extension services. The
namespace URI "urn:ietf:params:xml:ns:epp:secure-authinfo-transfer-
1.0" is used to signal support for the operational practice. The
client includes the namespace URI in an <svcExtension> <extURI>
element of the [RFC5730] <login> Command. The server includes the
namespace URI in an <svcExtension> <extURI> element of the [RFC5730]
Greeting.
A client that receives the namespace URI in the server's Greeting
extension services can expect the following supported behavior by the
server:
1. Support an empty authorization information value with a create
command.
2. Support unsetting authorization information with an update
command.
3. Support validating authorization information with an info
command.
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4. Support not returning an indication whether the authorization
information is set or unset to the non-sponsoring registrar.
5. Support returning an empty authorization information value to the
sponsoring registrar when the authorization information is set in
an info response.
6. Support allowing for the passing of a matching non-empty
authorization information value to authorize a transfer.
7. Support automatically unsetting the authorization information
upon a successful completion of transfer.
A server that receives the namespace URI in the client's <login>
Command extension services, can expect the following supported
behavior by the client:
1. Support generation of authorization information using a secure
random value.
2. Support only setting the authorization information when there is
a transfer in process.
4. Secure Authorization Information
The authorization information in the EPP RFCs ([RFC5731] and
[RFC5733]) that support transfer use password-based authorization
information ([RFC5731] with the <domain:pw> element and [RFC5733]
with the <contact:pw> element). Other EPP objects that support
password-based authorization information for transfer can use the
Secure Authorization Information defined in this document. For the
authorization information to be secure, it must be generated using a
strong random value and have a short time-to-live (TTL). The
security of the authorization information is defined in the following
sections.
4.1. Secure Random Authorization Information
For authorization information to be secure, it MUST be generated
using a secure random value. The authorization information is
treated as a password, and the required length L of a password,
rounded up to the largest whole number, is based on the size N of the
set of characters and the desired entropy H, in the equation L =
ROUNDUP(H / log2 N). Given a target entropy, the required length can
be calculated after deciding on the set of characters that will be
randomized. In accordance with current best practices and noting
that the authorization information is a machine-generated value, the
implementation SHOULD use at least 128 bits of entropy as the value
of H. The lengths below are calculated using that value.
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Calculation of the required length with 128 bits of entropy and with
the set of all printable ASCII characters except space (0x20), which
consists of the 94 characters 0x21-0x7E.
ROUNDUP(128 / log2 94) =~ ROUNDUP(128 / 6.55) =~ ROUNDUP(19.54) = 20
Calculation of the required length with 128 bits of entropy and with
the set of case insensitive alphanumeric characters, which consists
of 36 characters (a-z A-Z 0-9).
ROUNDUP(128 / log2 36) =~ ROUNDUP(128 / 5.17) =~ ROUNDUP(24.76) = 25
The strength of the random authorization information is dependent on
the random number generator. Suitably strong random number
generators are available in a wide variety of implementation
environments, including the interfaces listed in Sections 7.1.2 and
7.1.3 of [RFC4086]. In environments that do not provide interfaces
to strong random number generators, the practices defined in
[RFC4086] and section 4.7.1 of the NIST Federal Information
Processing Standards (FIPS) Publication 140-2 [FIPS-140-2] can be
followed to produce random values that will be resistant to attack.
4.2. Authorization Information Time-To-Live (TTL)
The authorization information SHOULD only be set when there is a
transfer in process. This implies that the authorization information
has a Time-To-Live (TTL) by which the authorization information is
cleared when the TTL expires. The EPP RFCs have no definition of
TTL, but since the server supports the setting and unsetting of the
authorization information by the sponsoring registrar, the sponsoring
registrar can apply a TTL based on client policy. The TTL client
policy may be based on proprietary registrar-specific criteria, which
provides for a transfer-specific TTL tuned for the particular
circumstances of the transaction. The sponsoring registrar will be
aware of the TTL and the sponsoring registrar MUST inform the
registrant of the TTL when the authorization information is provided
to the registrant.
4.3. Authorization Information Storage and Transport
To protect the disclosure of the authorization information, the
following requirements apply:
1. The authorization information MUST be stored by the registry
using a strong one-way cryptographic hash, with at least a
256-bit hash function, such as SHA-256 [FIPS-180-4], and with a
per-authorization information random salt, with at least 128
bits.
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2. Empty authorization information MUST be stored as an undefined
value that is referred to as a NULL value. The representation of
a NULL (undefined) value is dependent on the type of database
used.
3. The authorization information MUST NOT be stored by the losing
registrar.
4. The authorization information MUST only be stored by the gaining
registrar as a "transient" value in support of the transfer
process.
5. The plain text version of the authorization information MUST NOT
be written to any logs by a registrar or the registry, nor
otherwise recorded where it will persist beyond the transfer
process.
6. All communication that includes the authorization information
MUST be over an encrypted channel, such as defined in [RFC5734]
for EPP.
7. The registrar's interface for communicating the authorization
information with the registrant MUST be over an authenticated and
encrypted channel.
4.4. Authorization Information Matching
To support the authorization information TTL, as defined in
Section 4.2, the authorization information must have either a set or
unset state. Authorization information that is unset is stored with
a NULL (undefined) value. Based on the requirement to store the
authorization information using a strong one-way cryptographic hash,
as defined in Section 4.3, authorization information that is set is
stored with a non-NULL hashed value. The empty authorization
information is used as input in both the create command (Section 5.1)
and the update command (Section 5.2) to define the unset state. The
matching of the authorization information in the info command
(Section 5.3) and the transfer request command (Section 5.4) is based
on the following rules:
1. Any input authorization information value MUST NOT match an unset
authorization information value. This includes empty
authorization information, such as <domain:null/> or <domain:pw/>
in [RFC5731], and non-empty authorization information, such as
<domain:pw>2fooBAR</domain:pw> in [RFC5731].
2. An empty input authorization information value MUST NOT match any
set authorization information value.
3. A non-empty input authorization information value MUST be hashed
and matched against the set authorization information value,
which is stored using the same hash algorithm.
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5. Create, Transfer, and Secure Authorization Information
To secure the transfer process using secure authorization
information, as defined in Section 4, the client and server need to
implement steps where the authorization information is set only when
a transfer is actively in process and ensure that the authorization
information is stored securely and transported only over secure
channels. The steps in management of the authorization information
for transfers include:
1. Registrant requests to register the object with the registrar.
Registrar sends the create command, with an empty authorization
information value, to the registry, as defined in Section 5.1.
2. Registrant requests from the losing registrar the authorization
information to provide to the gaining registrar.
3. Losing registrar generates a secure random authorization
information value, sends it to the registry as defined in
Section 5.2, and provides it to the registrant.
4. Registrant provides the authorization information value to the
gaining registrar.
5. Gaining registrar optionally verifies the authorization
information with the info command to the registry, as defined in
Section 5.3.
6. Gaining registrar sends the transfer request with the
authorization information to the registry, as defined in
Section 5.4.
7. If the transfer successfully completes, the registry
automatically unsets the authorization information; otherwise the
losing registrar unsets the authorization information when the
TTL expires, as defined in Section 5.2.
The following sections outline the practices of the EPP commands and
responses between the registrar and the registry that supports secure
authorization information for transfer.
5.1. Create Command
For a create command, the registry MUST allow for the passing of an
empty authorization information value and MAY disallow for the
passing of a non-empty authorization information value. By having an
empty authorization information value on create, the object is
initially not in the transfer process. Any EPP object extension that
supports setting the authorization information with a
"eppcom:pwAuthInfoType" element can have an empty authorization
information value passed. Examples of such extensions are [RFC5731]
and [RFC5733].
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Example of passing an empty authorization information value in an
[RFC5731] domain name create command:
C:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
C:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0">
C: <command>
C: <create>
C: <domain:create
C: xmlns:domain="urn:ietf:params:xml:ns:domain-1.0">
C: <domain:name>example.com</domain:name>
C: <domain:authInfo>
C: <domain:pw/>
C: </domain:authInfo>
C: </domain:create>
C: </create>
C: <clTRID>ABC-12345</clTRID>
C: </command>
C:</epp>
Example of passing an empty authorization information value in an
[RFC5733] contact create command:
C:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
C:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0">
C: <command>
C: <create>
C: <contact:create
C: xmlns:contact="urn:ietf:params:xml:ns:contact-1.0">
C: <contact:id>sh8013</contact:id>
C: <contact:postalInfo type="int">
C: <contact:name>John Doe</contact:name>
C: <contact:addr>
C: <contact:city>Dulles</contact:city>
C: <contact:cc>US</contact:cc>
C: </contact:addr>
C: </contact:postalInfo>
C: <contact:email>jdoe@example.com</contact:email>
C: <contact:authInfo>
C: <contact:pw/>
C: </contact:authInfo>
C: </contact:create>
C: </create>
C: <clTRID>ABC-12345</clTRID>
C: </command>
C:</epp>
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5.2. Update Command
For an update command, the registry MUST allow for the setting and
unsetting of the authorization information. The registrar sets the
authorization information by first generating a strong, random
authorization information value, based on Section 4.1, and setting it
in the registry in the update command. The importance of generating
strong authorization information values cannot be overstated: secure
transfers are very important to the Internet to mitigate damage in
the form of theft, fraud, and other abuse. It is critical that
registrars only use strong, randomly generated authorization
information values.
Because of this, registries may validate the randomness of the
authorization information based on the length and character set
required by the registry. For example, validating an authorization
value contains a combination of upper-case, lower-case, and non-
alphanumeric characters, in an attempt to assess the strength of the
value, and return an EPP error result of 2202 if the check fails.
Such checks are, by their nature, heuristic and imperfect, and may
identify well-chosen authorization information values as being not
sufficiently strong. Registrars, therefore, must be prepared for an
error response of 2202, "Invalid authorization information", and
respond by generating a new value and trying again, possibly more
than once.
Often, the registrar has the "clientTransferProhibited" status set,
so to start the transfer process, the "clientTransferProhibited"
status needs to be removed, and the strong, random authorization
information value needs to be set. The registrar MUST define a time-
to-live (TTL), as defined in Section 4.2, where if the TTL expires
the registrar will unset the authorization information.
Example of removing the "clientTransferProhibited" status and setting
the authorization information in an [RFC5731] domain name update
command:
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C:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
C:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0">
C: <command>
C: <update>
C: <domain:update
C: xmlns:domain="urn:ietf:params:xml:ns:domain-1.0">
C: <domain:name>example.com</domain:name>
C: <domain:rem>
C: <domain:status s="clientTransferProhibited"/>
C: </domain:rem>
C: <domain:chg>
C: <domain:authInfo>
C: <domain:pw>LuQ7Bu@w9?%+_HK3cayg$55$LSft3MPP
C: </domain:pw>
C: </domain:authInfo>
C: </domain:chg>
C: </domain:update>
C: </update>
C: <clTRID>ABC-12345-XYZ</clTRID>
C: </command>
C:</epp>
When the registrar-defined TTL expires, the sponsoring registrar MUST
cancel the transfer process by unsetting the authorization
information value and MAY add back statuses like the
"clientTransferProbited" status. Any EPP object extension that
supports setting the authorization information with a
"eppcom:pwAuthInfoType" element, can have an empty authorization
information value passed. Examples of such extensions are [RFC5731]
and [RFC5733]. Setting an empty authorization information value
unsets the authorization information. [RFC5731] supports an explicit
mechanism of unsetting the authorization information, by passing the
<domain:null> authorization information value. The registry MUST
support unsetting the authorization information by accepting an empty
authorization information value and accepting an explicit unset
element if it is supported by the object extension.
Example of adding the "clientTransferProhibited" status and unsetting
the authorization information explicitly in an [RFC5731] domain name
update command:
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C:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
C:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0">
C: <command>
C: <update>
C: <domain:update
C: xmlns:domain="urn:ietf:params:xml:ns:domain-1.0">
C: <domain:name>example.com</domain:name>
C: <domain:add>
C: <domain:status s="clientTransferProhibited"/>
C: </domain:add>
C: <domain:chg>
C: <domain:authInfo>
C: <domain:null/>
C: </domain:authInfo>
C: </domain:chg>
C: </domain:update>
C: </update>
C: <clTRID>ABC-12345-XYZ</clTRID>
C: </command>
C:</epp>
Example of unsetting the authorization information with an empty
authorization information value in an [RFC5731] domain name update
command:
C:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
C:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0">
C: <command>
C: <update>
C: <domain:update
C: xmlns:domain="urn:ietf:params:xml:ns:domain-1.0">
C: <domain:name>example.com</domain:name>
C: <domain:add>
C: <domain:status s="clientTransferProhibited"/>
C: </domain:add>
C: <domain:chg>
C: <domain:authInfo>
C: <domain:pw/>
C: </domain:authInfo>
C: </domain:chg>
C: </domain:update>
C: </update>
C: <clTRID>ABC-12345-XYZ</clTRID>
C: </command>
C:</epp>
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Example of unsetting the authorization information with an empty
authorization information value in an [RFC5733] contact update
command:
C:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
C:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0">
C: <command>
C: <update>
C: <contact:update
C: xmlns:contact="urn:ietf:params:xml:ns:contact-1.0">
C: <contact:id>sh8013</contact:id>
C: <contact:chg>
C: <contact:authInfo>
C: <contact:pw/>
C: </contact:authInfo>
C: </contact:chg>
C: </contact:update>
C: </update>
C: <clTRID>ABC-12345-XYZ</clTRID>
C: </command>
C:</epp>
5.3. Info Command and Response
For an info command, the registry MUST allow for the passing of a
non-empty authorization information value for verification. The
gaining registrar can pre-verify the authorization information
provided by the registrant prior to submitting the transfer request
with the use of the info command. The registry compares the hash of
the passed authorization information with the hashed authorization
information value stored for the object. When the authorization
information is not set or the passed authorization information does
not match the previously set value, the registry MUST return an EPP
error result code of 2202 [RFC5730].
Example of passing a non-empty authorization information value in an
[RFC5731] domain name info command to verify the authorization
information value:
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C:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
C:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0">
C: <command>
C: <info>
C: <domain:info
C: xmlns:domain="urn:ietf:params:xml:ns:domain-1.0">
C: <domain:name>example.com</domain:name>
C: <domain:authInfo>
C: <domain:pw>LuQ7Bu@w9?%+_HK3cayg$55$LSft3MPP
C: </domain:pw>
C: </domain:authInfo>
C: </domain:info>
C: </info>
C: <clTRID>ABC-12345</clTRID>
C: </command>
C:</epp>
The info response in object extensions, such as [RFC5731] and
[RFC5733], MUST NOT include the optional authorization information
element with a non-empty authorization value. The authorization
information is stored as a hash in the registry, so returning the
plain text authorization information is not possible, unless a valid
plain text authorization information is passed in the info command.
The registry MUST NOT return any indication of whether the
authorization information is set or unset to the non-sponsoring
registrar by not returning the authorization information element in
the response. The registry MAY return an indication to the
sponsoring registrar that the authorization information is set by
using an empty authorization information value. The registry MAY
return an indication to the sponsoring registrar that the
authorization information is unset by not returning the authorization
information element.
Example of returning an empty authorization information value in an
[RFC5731] domain name info response to indicate to the sponsoring
registrar that the authorization information is set:
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S:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
S:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0">
S: <response>
S: <result code="1000">
S: <msg>Command completed successfully</msg>
S: </result>
S: <resData>
S: <domain:infData
S: xmlns:domain="urn:ietf:params:xml:ns:domain-1.0">
S: <domain:name>example.com</domain:name>
S: <domain:roid>EXAMPLE1-REP</domain:roid>
S: <domain:status s="ok"/>
S: <domain:clID>ClientX</domain:clID>
S: <domain:authInfo>
S: <domain:pw/>
S: </domain:authInfo>
S: </domain:infData>
S: </resData>
S: <trID>
S: <clTRID>ABC-12345</clTRID>
S: <svTRID>54322-XYZ</svTRID>
S: </trID>
S: </response>
S:</epp>
5.4. Transfer Request Command
For a Transfer Request Command, the registry MUST allow for the
passing of a non-empty authorization information value to authorize a
transfer. The registry compares the hash of the passed authorization
information with the hashed authorization information value stored
for the object. When the authorization information is not set or the
passed authorization information does not match the previously set
value, the registry MUST return an EPP error result code of 2202
[RFC5730]. Whether the transfer occurs immediately or is pending is
up to server policy. When the transfer occurs immediately, the
registry MUST return the EPP success result code of 1000 and when the
transfer is pending, the registry MUST return the EPP success result
code of 1001. The losing registrar MUST be informed of a successful
transfer request using an EPP poll message.
Example of passing a non-empty authorization information value in an
[RFC5731] domain name transfer request command to authorize the
transfer:
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C:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
C:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0">
C: <command>
C: <transfer op="request">
C: <domain:transfer
C: xmlns:domain="urn:ietf:params:xml:ns:domain-1.0">
C: <domain:name>example1.com</domain:name>
C: <domain:authInfo>
C: <domain:pw>LuQ7Bu@w9?%+_HK3cayg$55$LSft3MPP
C: </domain:pw>
C: </domain:authInfo>
C: </domain:transfer>
C: </transfer>
C: <clTRID>ABC-12345</clTRID>
C: </command>
C:</epp>
Upon successful completion of the transfer, the registry MUST
automatically unset the authorization information. If the transfer
request is not submitted within the time-to-live (TTL) (Section 4.2)
or the transfer is cancelled or rejected, the registrar MUST unset
the authorization information as defined in Section 5.2.
6. Transition Considerations
The goal of the transition considerations to the practice defined in
this document, referred to as the Secure Authorization Information
Model, is to minimize the impact to the registrars by supporting
incremental steps of adoption. The transition steps are dependent on
the starting point of the registry. Registries may have different
starting points, since some of the elements of the Secure
Authorization Information Model may have already been implemented.
The considerations assume a starting point, referred to as the
Classic Authorization Information Model, that have the following
steps in the management of the authorization information for
transfers:
1. Registrant requests to register the object with the registrar.
Registrar sends the create command, with a non-empty
authorization information value, to the registry. The registry
stores the authorization information as an encrypted value and
requires a non-empty authorization information value for the life
of the object. The registrar may store the long-lived
authorization information.
2. At the time of transfer, Registrant requests from the losing
registrar the authorization information to provide to the gaining
registrar.
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3. Losing registrar retrieves the locally stored authorization
information or queries the registry for authorization information
using the info command, and provides it to the registrant. If
the registry is queried, the authorization information is
decrypted and the plain text authorization information is
returned in the info response to the registrar.
4. Registrant provides the authorization information value to the
gaining registrar.
5. Gaining registrar optionally verifies the authorization
information with the info command to the registry, by passing the
authorization information in the info command to the registry.
6. Gaining registrar sends the transfer request with the
authorization information to the registry. The registry will
decrypt the stored authorization information to compare to the
passed authorization information.
7. If the transfer successfully completes, the authorization
information is not touched by the registry and may be updated by
the gaining registrar using the update command. If the transfer
is cancelled or rejected, the losing registrar may reset the
authorization information using the update command.
The gaps between the Classic Authorization Information Model and the
Secure Authorization Information Model include:
1. Registry requirement for a non-empty authorization information
value on create and for the life of the object versus the
authorization information not being set on create and only being
set when a transfer is in process.
2. Registry not allowing the authorization information to be unset
versus supporting the authorization to be unset in the update
command.
3. Registry storing the authorization information as an encrypted
value versus as a hashed value.
4. Registry support for returning the authorization information
versus not returning the authorization information in the info
response.
5. Registry not touching the authorization information versus the
registry automatically unsetting the authorization information
upon a successful transfer.
6. Registry may validate a shorter authorization information value
using password complexity rules versus validating the randomness
of a longer authorization information value that meets the
required bits of entropy.
The transition can be handled in the three phases defined in the sub-
sections Section 6.1, Section 6.2, Section 6.3.
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6.1. Transition Phase 1 - Features
The goal of the "Transition Phase 1 - Features" is to implement the
needed features in EPP so that the registrar can optionally implement
the Secure Authorization Information Model. The features to
implement are broken out by the command and responses below:
Create Command: Change the create command to make the authorization
information optional, by allowing both a non-empty value and an
empty value. This enables a registrar to optionally create
objects without an authorization information value, as defined in
Section 5.1.
Update Command: Change the update command to allow unsetting the
authorization information, as defined in Section 5.2. This
enables the registrar to optionally unset the authorization
information when the TTL expires or when the transfer is cancelled
or rejected.
Transfer Approve Command and Transfer Auto-Approve: Change the
transfer approve command and the transfer auto-approve to
automatically unset the authorization information. This sets the
default state of the object to not have the authorization
information set. The registrar implementing the Secure
Authorization Information Model will not set the authorization
information for an inbound transfer and the registrar implementing
the Classic Authorization Information Model will set the new
authorization information upon the successful transfer.
Info Response: Change the info command to not return the
authorization information in the info response, as defined in
Section 5.3. This sets up the implementation of "Transition Phase
2 - Storage", since the dependency in returning the authorization
information in the info response will be removed. This feature is
the only one that is not an optional change to the registrar that
has the potential of breaking the client, so it's recommended that
the registry provide notice of the change.
Info Command and Transfer Request: Change the info command and the
transfer request to ensure that a registrar cannot get an
indication that the authorization information is set or not set by
returning the EPP error result code of 2202 when comparing a
passed authorization to a non-matching set authorization
information value or an unset value.
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6.2. Transition Phase 2 - Storage
The goal of the "Transition Phase 2 - Storage" is to transition the
registry to use hashed authorization information instead of encrypted
authorization information. There is no direct impact to the
registrars, since the only visible indication that the authorization
information has been hashed is by not returning the set authorization
information in the info response, which is addressed in Transition
Phase 1 - Features (Section 6.1). There are three steps to
transition the authorization information storage, which includes:
Hash New Authorization Information Values: Change the create command
and the update command to hash instead of encrypting the
authorization information.
Supporting Comparing Against Encrypted and Hashed Authorization
Information: Change the info command and the transfer request
command to be able to compare a passed authorization information
value with either a hashed or encrypted authorization information
value. This requires that the stored values are self-identifying
as being in hashed or encrypted form.
Hash Existing Encrypted Authorization Information Values: Convert
the encrypted authorization information values stored in the
registry database to hashed values. The update is not a visible
change to the registrar. The conversion can be done over a period
of time depending on registry policy.
6.3. Transition Phase 3 - Enforcement
The goal of the "Transition Phase 3 - Enforcement" is to complete the
implementation of the "Secure Authorization Information Model", by
enforcing the following:
Disallow Authorization Information on Create Command: Change the
create command to not allow for the passing of a non-empty
authorization information value. This behavior has the potential
of breaking the client, so it's recommended that the registry
provide notice of the change.
Validate the Strong Random Authorization Information: Change the
validation of the authorization information in the update command
to ensure at least 128 bits of entropy.
7. IANA Considerations
7.1. XML Namespace
This document uses URNs to describe XML namespaces conforming to a
registry mechanism described in [RFC3688]. The following URI
assignment is requested of IANA:
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Registration request for the secure authorization information for
transfer namespace:
URI: urn:ietf:params:xml:ns:epp:secure-authinfo-transfer-1.0
Registrant Contact: IESG
XML: None. Namespace URIs do not represent an XML specification.
7.2. EPP Extension Registry
The EPP operational practice described in this document should be
registered by the IANA in the EPP Extension Registry described in
[RFC7451]. The details of the registration are as follows:
Name of Extension: "Extensible Provisioning Protocol (EPP) Secure
Authorization Information for Transfer"
Document status: Standards Track
Reference: (insert reference to RFC version of this document)
Registrant Name and Email Address: IESG, <iesg@ietf.org>
TLDs: Any
IPR Disclosure: None
Status: Active
Notes: None
8. Implementation Status
Note to RFC Editor: Please remove this section and the reference to
RFC 7942 [RFC7942] before publication.
This section records the status of known implementations of the
protocol defined by this specification at the time of posting of this
Internet-Draft, and is based on a proposal described in RFC 7942
[RFC7942]. The description of implementations in this section is
intended to assist the IETF in its decision processes in progressing
drafts to RFCs. Please note that the listing of any individual
implementation here does not imply endorsement by the IETF.
Furthermore, no effort has been spent to verify the information
presented here that was supplied by IETF contributors. This is not
intended as, and must not be construed to be, a catalog of available
implementations or their features. Readers are advised to note that
other implementations may exist.
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According to RFC 7942 [RFC7942], "this will allow reviewers and
working groups to assign due consideration to documents that have the
benefit of running code, which may serve as evidence of valuable
experimentation and feedback that have made the implemented protocols
more mature. It is up to the individual working groups to use this
information as they see fit".
8.1. Verisign EPP SDK
Organization: Verisign Inc.
Name: Verisign EPP SDK
Description: The Verisign EPP SDK includes both a full client
implementation and a full server stub implementation of draft-ietf-
regext-secure-authinfo-transfer.
Level of maturity: Development
Coverage: All aspects of the protocol are implemented.
Licensing: GNU Lesser General Public License
Contact: jgould@verisign.com
URL: https://www.verisign.com/en_US/channel-resources/domain-
registry-products/epp-sdks
8.2. RegistryEngine EPP Service
Organization: CentralNic
Name: RegistryEngine EPP Service
Description: Generic high-volume EPP service for gTLDs, ccTLDs and
SLDs
Level of maturity: Deployed in CentralNic's production environment as
well as two other gTLD registry systems, and two ccTLD registry
systems.
Coverage: Authorization Information is "write only" in that the
registrars can set the Authorization Information, but not get the
Authorization Information in the Info Response.
Licensing: Proprietary In-House software
Contact: epp@centralnic.com
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URL: https://www.centralnic.com
9. Security Considerations
Section 4.1 defines the use a secure random value for the generation
of the authorization information. The client SHOULD choose a length
and set of characters that results in at least 128 bits of entropy.
Section 4.2 defines the use of an authorization information Time-To-
Live (TTL). The registrar SHOULD only set the authorization
information during the transfer process by the server support for
setting and unsetting the authorization information. The TTL value
is up to registrar policy and the sponsoring registrar MUST inform
the registrant of the TTL when providing the authorization
information to the registrant.
Section 4.3 defines the storage and transport of authorization
information. The losing registrar MUST NOT store the authorization
information and the gaining registrar MUST only store the
authorization information as a "transient" value during the transfer
process, where the authorization information MUST NOT be stored after
the end of the transfer process. The registry MUST store the
authorization information using a one-way cryptographic hash of at
least 256 bits and with a per-authorization information random salt,
with at least 128 bits. All communication that includes the
authorization information MUST be over an encrypted channel. The
plain text authorization information MUST NOT be written to any logs
by the registrar or the registry.
Section 4.4 defines the matching of the authorization information
values. The registry stores an unset authorization information as a
NULL (undefined) value to ensure that an empty input authorization
information never matches it. The method used to define a NULL
(undefined) value is database specific.
10. Acknowledgements
The authors wish to thank the following persons for their feedback
and suggestions: Michael Bauland, Martin Casanova, Scott Hollenbeck,
Benjamin Kaduk, Jody Kolker, Barry Leiba, Patrick Mevzek, Matthew
Pozun, Srikanth Veeramachaneni, and Ulrich Wisser.
11. References
11.1. Normative References
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[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
DOI 10.17487/RFC3688, January 2004,
<https://www.rfc-editor.org/info/rfc3688>.
[RFC4086] Eastlake 3rd, D., Schiller, J., and S. Crocker,
"Randomness Requirements for Security", BCP 106, RFC 4086,
DOI 10.17487/RFC4086, June 2005,
<https://www.rfc-editor.org/info/rfc4086>.
[RFC5730] Hollenbeck, S., "Extensible Provisioning Protocol (EPP)",
STD 69, RFC 5730, DOI 10.17487/RFC5730, August 2009,
<https://www.rfc-editor.org/info/rfc5730>.
[RFC5731] Hollenbeck, S., "Extensible Provisioning Protocol (EPP)
Domain Name Mapping", STD 69, RFC 5731,
DOI 10.17487/RFC5731, August 2009,
<https://www.rfc-editor.org/info/rfc5731>.
[RFC5733] Hollenbeck, S., "Extensible Provisioning Protocol (EPP)
Contact Mapping", STD 69, RFC 5733, DOI 10.17487/RFC5733,
August 2009, <https://www.rfc-editor.org/info/rfc5733>.
[RFC5734] Hollenbeck, S., "Extensible Provisioning Protocol (EPP)
Transport over TCP", STD 69, RFC 5734,
DOI 10.17487/RFC5734, August 2009,
<https://www.rfc-editor.org/info/rfc5734>.
[RFC7942] Sheffer, Y. and A. Farrel, "Improving Awareness of Running
Code: The Implementation Status Section", BCP 205,
RFC 7942, DOI 10.17487/RFC7942, July 2016,
<https://www.rfc-editor.org/info/rfc7942>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
[RFC8499] Hoffman, P., Sullivan, A., and K. Fujiwara, "DNS
Terminology", BCP 219, RFC 8499, DOI 10.17487/RFC8499,
January 2019, <https://www.rfc-editor.org/info/rfc8499>.
11.2. Informative References
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[FIPS-140-2]
National Institute of Standards and Technology, U.S.
Department of Commerce, "NIST Federal Information
Processing Standards (FIPS) Publication 140-2", May 2001,
<https://csrc.nist.gov/publications/detail/fips/140/2/
final>.
[FIPS-180-4]
National Institute of Standards and Technology, U.S.
Department of Commerce, "Secure Hash Standard, NIST
Federal Information Processing Standards (FIPS)
Publication 180-4", August 2015,
<https://csrc.nist.gov/publications/detail/fips/180/4/
final>.
[RFC7451] Hollenbeck, S., "Extension Registry for the Extensible
Provisioning Protocol", RFC 7451, DOI 10.17487/RFC7451,
February 2015, <https://www.rfc-editor.org/info/rfc7451>.
Appendix A. Change History
A.1. Change from 00 to 01
1. Filled in the "Implementation Status" section with the inclusion
of the "Verisign EPP SDK" and "RegistryEngine EPP Service"
implementations.
2. Made small wording corrections based on private feedback.
3. Added content to the "Acknowledgements" section.
A.2. Change from 01 to 02
1. Revised the language used for the storage of the authorization
information based on the feedback from Patrick Mevzek and Jody
Kolker.
A.3. Change from 02 to 03
1. Updates based on the feedback from the interim REGEXT meeting
held at ICANN-66:
1. Section 3.3, include a reference to the hash algorithm to
use. Broke the requirements into a list and included a the
reference the text ', with at least a 256-bit hash function,
such as SHA-256'.
2. Add a Transition Considerations section to cover the
transition from the classic authorization information
security model in the EPP RFCs to the model defined in the
document.
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3. Add a statement to the Introduction that elements of the
practice can be used for purposes other than transfer, but
with a caveat.
2. Updates based on the review by Michael Bauland, that include:
1. In section 2, change 'there are three actors' to 'there are
three types of actors' to cover the case with transfers that
has two registrar actors (losing and gaining).
2. In section 3.1, change the equations equals to be
approximately equal by using '=~' instead of '=', where
applicable.
3. In section 3.3, change 'MUST be over an encrypted channel,
such as RFC5734' to 'MUST be over an encrypted channel, such
as defined in RFC5734'.
4. In section 4.1, remove the optional RFC 5733 elements from
the contact create, which includes the <contact:voice>,
<contact:fax>, <contact:disclose>, <contact:org>,
<contact:street>, <contact:sp>, and <contact:cc> elements.
5. In section 4.2, changed 'Example of unsetting the
authorization information explicitly in an [RFC5731] domain
name update command.' to 'Example of adding the
"clientTransferProhibited" status and unsetting the
authorization information explicitly in an [RFC5731] domain
name update command.'
6. In section 4.3, cover a corner case of the ability to return
the authorization information when it's passed in the info
command.
7. In section 4.4, change 'If the transfer does not complete
within the time-to-live (TTL)' to 'If the transfer is not
initiated within the time-to-live (TTL)', since the TTL is
the time between setting the authorization information and
when it's successfully used in a transfer request. Added the
case of unsetting the authorization information when the
transfer is cancelled or rejected.
3. Updates based on the authorization information messages by Martin
Casanova on the REGEXT mailing list, that include:
1. Added section 3.4 'Authorization Information Matching' to
clarify how the authorization information is matched, when
there is set and unset authorization information in the
database and empty and non-empty authorization information
passed in the info and transfer commands.
2. Added support for signaling that the authorization
information is set or unset to the sponsoring registrar with
the inclusion of an empty authorization information element
in the response to indicate that the authorization
information is set and the exclusion of the authorization
information element in the response to indicate that the
authorization information is unset.
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4. Made the capitalization of command and response references
consistent by uppercasing section and item titles and lowercasing
references elsewhere.
A.4. Change from 03 to REGEXT 00
1. Changed to regext working group draft by changing draft-gould-
regext-secure-authinfo-transfer to draft-ietf-regext-secure-
authinfo-transfer.
A.5. Change from REGEXT 00 to REGEXT 01
1. Added the "Signaling Client and Server Support" section to
describe the mechanism to signal support for the BCP by the
client and the server.
2. Added the "IANA Considerations" section with the registration of
the secure authorization for transfer XML namespace and the
registration of the EPP Best Current Practice (BCP) in the EPP
Extension Registry.
A.6. Change from REGEXT 01 to REGEXT 02
1. Added inclusion of random salt for the hashed authorization
information, based on feedback from Ulrich Wisser.
2. Added clarification that the representation of a NULL (undefined)
value is dependent on the type of database, based on feedback
from Patrick Mevzek.
3. Filled in the Security Considerations section.
A.7. Change from REGEXT 02 to REGEXT 03
1. Updated the XML namespace to urn:ietf:params:xml:ns:epp:secure-
authinfo-transfer-1.0, which removed bcp from the namespace and
bumped the version from 0.1 and 1.0. Inclusion of bcp in the XML
namespace was discussed at the REGEXT interim meeting.
2. Replaced Auhtorization with Authorization based on a review by
Jody Kolker.
A.8. Change from REGEXT 03 to REGEXT 04
1. Converted from xml2rfc v2 to v3.
2. Updated Acknowledgements to match the approach taken by the RFC
Editor with draft-ietf-regext-login-security.
3. Changed from Best Current Practice (BCP) to Standards Track based
on mailing list discussion.
A.9. Change from REGEXT 04 to REGEXT 05
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1. Fixed IDNITS issues, including moving RFC7451 to Informative
References section.
A.10. Change from REGEXT 05 to REGEXT 06
Updates based on the Barry Leiba (AD) feedback:
1. Simplified the abstract based on the proposal provided.
2. In the Introduction, split the first paragraph by starting a new
paragraph at "This document".
3. In section 1.1, updated to use the new BCP 14 boilerplate and
add a normative reference to RFC 8174.
4. In section 4, Updated the phrasing to "For the authorization
information to be secure it must be generated using a strong
random value and have a short time-to-live (TTL).".
5. In section 4.1, removed the first two unnecessary calculations
and condensed the introduction of the section.
6. In section 4.1, added the use of the normative SHOULD for use of
at least 128 bits of entropy.
7. Added an informative reference to FIPS 180-4 for the SHA-256
references.
8. Normalized the way that the "empty and non-empty authorization
information values" are referenced, which a few exceptions.
9. In section 4, revised the first sentence to explicitly reference
the use of the <domain:pw> and <contact:pw> elements for
password-based authorization information.
10. In section 4.4, revised the language associated with the storage
of the authorization information to be cleaner.
11. In section 4.4, added "set" in the sentence "An empty input
authorization information value MUST NOT match any set
authorization information value."
12. In section 5.1 and 5.2, clarified the references to RFC5731 and
RFC5733 as examples of object extensions that use the
"eppcom:pwAuthInfoType" element.
13. In section 5.2, updated language for the validation of the
randomness of the authorization information, based on an offline
review by Barry Leiba, Benjamin Kaduk, and Roman Danyliw.
14. In section 9, changed "49 bits of entropy" to "128 bits of
entropy".
In section 3, replaced the reference to BCP with operational
practice, since the draft is not defined as a BCP.
A.11. Change from REGEXT 06 to REGEXT 07
1. Updates based on the Lars Eggert feedback:
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1. Updated Section 1, Paragraph 4 to read "The operational
practice will require the client to not store the
authorization information and".
2. Updated each of the example references to end with a colon
instead of a period.
3. Updated Section 1, Paragraph 3 to read "provide secure
authorization information used for transfers."
4. Updated Section 3, Paragraph 3 to read "extension services
can expect".
5. Updated Section 4, Paragraph 2 to read "authorization
information to be secure, it must".
6. Updated Section 4.2, Paragraph 2 to read "authorization
information by the sponsoring registrar, the".
7. Updated Section 4.2, Paragraph 2 to read "proprietary
registrar-specific criteria, which".
8. Updated Section 4.3, Paragraph 3 to read "256-bit hash
function, such as SHA-256".
9. Updated Section 4.3, Paragraph 3 to read "a NULL (undefined)
value".
10. Updated Section 5, Paragraph 2 to read "To secure the
transfer process using secure authorization".
11. Updated Section 5.2, Paragraph 6 to read "Often, the
registrar has the "clientTransferProhibited" status set".
12. Updated Section 5.2, Paragraph 9 to read "MUST cancel cancel
the transfer process by unsetting the authorization
information value and MAY add back statuses".
13. Updated Section 5.2, Paragraph 9 to read
""eppcom:pwAuthInfoType" element can have".
2. Updated the first sentence of the abstract and introduction based
on the Rob Wilton feedback to help non-EPP readers on the what
and the who for transfers.
3. Removed the duplicate first paragraph of section 5.2 based on
feedback from Francesca Palombini.
4. Updates based on the Benjamin Kaduk feedback:
1. Added the second paragraph in the Introduction to provide
high-level motivation for the work.
2. Updated Section 1, changed "in any way" to "in any
substantial way".
3. Updated Section 1 by adding the sentence "All of these
features are compatible with the EPP RFCs, though not
mandatory to implement." for the "Short-Lived Authorization
Information".
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4. Updated the description of "Short-Lived Authorization
Information" in Section 1 to reference section 2.6 of
RFC5731 and change in nature of the authorization
information.
5. Updated Section 4.1, Paragraph 1 and 2 were merged with
modified language proposed by Benjamin Kaduk, which included
removing the reference to RFC4086 for length and entropy.
6. Updated rule #1 of Section 4.1 to add a second clarifying
sentence for what is meant by input authorization
information.
7. Updated Section 4.1 by replacing the last paragraph "The
strength of the random..." with a revised version.
8. Updated "retrieves the stored authorization information
locally" with "retrieves the locally stored authorization
information".
9. Updated Section 6.1 to include the recommendation that the
registry provide notice of the Info Response change.
10. Updated Section 6.2 to include the sentence "This requires
that the stored values are self-identifying as being in
hashed or encrypted form" for the "Supporting Comparing
Against Encrypted and Hashed Authorization Information"
step.
11. Updated Section 6.3 to include the recommendation that the
registry provide notice of the Create Command change.
12. Updated "written to any logs by the registrar or the
registry" to "written to any logs by a registrar or the
registry" to cover both the losing and the gaining
registrar.
13. Updated references to "with a random salt" to "with a per-
authorization information random salt, with at least 128
bits" to address sharing of salts and the size of the salts.
14. Updated the first paragraph of Section 9 to remove the
reference to defining a server policy for the length and set
of characters that are included in the randomization to
target the target entropy level.
15. Updated Section 9 by removing the sentence "A random number
generator (RNG) is preferable over the use of a pseudorandom
number generator (PRNG) when creating the authorization
information value."
16. Changed FIPS-140-2 from a normative reference to an
informative reference.
Authors' Addresses
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James Gould
VeriSign, Inc.
12061 Bluemont Way
Reston, VA 20190
United States of America
Email: jgould@verisign.com
URI: http://www.verisign.com
Richard Wilhelm
VeriSign, Inc.
12061 Bluemont Way
Reston, VA 20190
United States of America
Email: rwilhelm@verisign.com
URI: http://www.verisign.com
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