< draft-ietf-precis-saslprepbis-04.txt		draft-ietf-precis-saslprepbis-05.txt >
	PRECIS P. Saint-Andre		PRECIS P. Saint-Andre
	Internet-Draft Cisco Systems, Inc.		Internet-Draft Cisco Systems, Inc.
	Obsoletes: 4013 (if approved) A. Melnikov		Obsoletes: 4013 (if approved) A. Melnikov
	Intended status: Standards Track Isode Ltd		Intended status: Standards Track Isode Ltd
	Expires: February 5, 2014 August 4, 2013		Expires: April 21, 2014 October 18, 2013
	Preparation and Comparison of Internationalized Strings Representing		Preparation and Comparison of Internationalized Strings Representing
	Usernames and Passwords		Usernames and Passwords
	draft-ietf-precis-saslprepbis-04		draft-ietf-precis-saslprepbis-05
	Abstract		Abstract
	This document describes how to handle Unicode strings representing		This document describes methods for handling Unicode strings
	usernames and passwords. This profile is intended to be used by		representing usernames and passwords. This document obsoletes RFC
	protocols that exchange or otherwise make use of usernames and		4013.
	passwords. This document obsoletes RFC 4013.
	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
	working documents as Internet-Drafts. The list of current Internet-		working documents as Internet-Drafts. The list of current Internet-
	Drafts is at http://datatracker.ietf.org/drafts/current/.		Drafts is at http://datatracker.ietf.org/drafts/current/.
	Internet-Drafts are draft documents valid for a maximum of six months		Internet-Drafts are draft documents valid for a maximum of six months
	and may be updated, replaced, or obsoleted by other documents at any		and may be updated, replaced, or obsoleted by other documents at any
	time. It is inappropriate to use Internet-Drafts as reference		time. It is inappropriate to use Internet-Drafts as reference
	material or to cite them other than as "work in progress."		material or to cite them other than as "work in progress."
	This Internet-Draft will expire on February 5, 2014.		This Internet-Draft will expire on April 21, 2014.
	Copyright Notice		Copyright Notice
	Copyright (c) 2013 IETF Trust and the persons identified as the		Copyright (c) 2013 IETF Trust and the persons identified as the
	document authors. All rights reserved.		document authors. All rights reserved.
	This document is subject to BCP 78 and the IETF Trust's Legal		This document is subject to BCP 78 and the IETF Trust's Legal
	Provisions Relating to IETF Documents		Provisions Relating to IETF Documents
	(http://trustee.ietf.org/license-info) in effect on the date of		(http://trustee.ietf.org/license-info) in effect on the date of
	publication of this document. Please review these documents		publication of this document. Please review these documents
	skipping to change at page 2, line 14 ¶		skipping to change at page 2, line 13 ¶
	described in the Simplified BSD License.		described in the Simplified BSD License.
	Table of Contents		Table of Contents
	1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3		1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
	2. What the Username and Password Profiles Provide . . . . . . . 3		2. What the Username and Password Profiles Provide . . . . . . . 3
	3. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4		3. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4
	4. Usernames . . . . . . . . . . . . . . . . . . . . . . . . . . 4		4. Usernames . . . . . . . . . . . . . . . . . . . . . . . . . . 4
	4.1. Definition . . . . . . . . . . . . . . . . . . . . . . . . 4		4.1. Definition . . . . . . . . . . . . . . . . . . . . . . . . 4
	4.2. Preparation . . . . . . . . . . . . . . . . . . . . . . . 5		4.2. Preparation . . . . . . . . . . . . . . . . . . . . . . . 5
	5. Passwords . . . . . . . . . . . . . . . . . . . . . . . . . . 6		4.2.1. Case Mapping . . . . . . . . . . . . . . . . . . . . . 6
			5. Passwords . . . . . . . . . . . . . . . . . . . . . . . . . . 7
	5.1. Definition . . . . . . . . . . . . . . . . . . . . . . . . 7		5.1. Definition . . . . . . . . . . . . . . . . . . . . . . . . 7
	5.2. Preparation . . . . . . . . . . . . . . . . . . . . . . . 7		5.2. Preparation . . . . . . . . . . . . . . . . . . . . . . . 7
	6. Migration . . . . . . . . . . . . . . . . . . . . . . . . . . 8		6. Migration . . . . . . . . . . . . . . . . . . . . . . . . . . 8
	6.1. Usernames . . . . . . . . . . . . . . . . . . . . . . . . 8		6.1. Usernames . . . . . . . . . . . . . . . . . . . . . . . . 8
	6.2. Passwords . . . . . . . . . . . . . . . . . . . . . . . . 9		6.2. Passwords . . . . . . . . . . . . . . . . . . . . . . . . 9
	7. Security Considerations . . . . . . . . . . . . . . . . . . . 10		7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10
	7.1. Password/Passphrase Strength . . . . . . . . . . . . . . . 10		7.1. UsernameIdentifierClass . . . . . . . . . . . . . . . . . 10
	7.2. Identifier Comparison . . . . . . . . . . . . . . . . . . 10		7.2. PasswordFreeformClass . . . . . . . . . . . . . . . . . . 11
	7.3. Reuse of PRECIS . . . . . . . . . . . . . . . . . . . . . 10		8. Security Considerations . . . . . . . . . . . . . . . . . . . 11
	7.4. Reuse of Unicode . . . . . . . . . . . . . . . . . . . . . 11		8.1. Password/Passphrase Strength . . . . . . . . . . . . . . . 11
	8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 11		8.2. Identifier Comparison . . . . . . . . . . . . . . . . . . 11
	8.1. Use of IdentifierClass . . . . . . . . . . . . . . . . . . 11		8.3. Reuse of PRECIS . . . . . . . . . . . . . . . . . . . . . 12
	8.2. Use of FreeformClass . . . . . . . . . . . . . . . . . . . 11		8.4. Reuse of Unicode . . . . . . . . . . . . . . . . . . . . . 12
	9. References . . . . . . . . . . . . . . . . . . . . . . . . . . 12		9. References . . . . . . . . . . . . . . . . . . . . . . . . . . 12
	9.1. Normative References . . . . . . . . . . . . . . . . . . . 12		9.1. Normative References . . . . . . . . . . . . . . . . . . . 12
	9.2. Informative References . . . . . . . . . . . . . . . . . . 12		9.2. Informative References . . . . . . . . . . . . . . . . . . 12
	Appendix A. Differences from RFC 4013 . . . . . . . . . . . . . . 13		Appendix A. Differences from RFC 4013 . . . . . . . . . . . . . . 14
	Appendix B. Acknowledgements . . . . . . . . . . . . . . . . . . 14		Appendix B. Acknowledgements . . . . . . . . . . . . . . . . . . 14
	Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 14		Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 15
	1. Introduction		1. Introduction
	Usernames and passwords are widely used for authentication and		Usernames and passwords are widely used for authentication and
	authorization on the Internet, either directly when provided in		authorization on the Internet, either directly when provided in
	plaintext (as in the SASL PLAIN mechanism [RFC4616] or the HTTP Basic		plaintext (as in the SASL PLAIN mechanism [RFC4616] or the HTTP Basic
	scheme [RFC2617]) or indirectly when provided as the input to a		scheme [RFC2617]) or indirectly when provided as the input to a
	cryptographic algorithm such as a hash function (as in the SASL SCRAM		cryptographic algorithm such as a hash function (as in the SASL SCRAM
	mechanism [RFC5802] or the HTTP Digest scheme [RFC2617]). To		mechanism [RFC5802] or the HTTP Digest scheme [RFC2617]). To
	increase the likelihood that the input and comparison of usernames		increase the likelihood that the input and comparison of usernames
	and passwords will work in ways that make sense for typical users		and passwords will work in ways that make sense for typical users
	throughout the world, this document defines rules for preparing and		throughout the world, this document defines rules for preparing and
	comparing internationalized strings that represent usernames and		comparing internationalized strings that represent usernames and
	passwords.		passwords.
	The methods specified in this document define a PRECIS profile as		The methods specified in this document define two PRECIS profiles as
	explained in the PRECIS framework specification		explained in the PRECIS framework specification
	[I-D.ietf-precis-framework]. This document assumes that all strings		[I-D.ietf-precis-framework]. This document assumes that all strings
	are comprised of characters from the Unicode character set [UNICODE],		are comprised of characters from the Unicode character set [UNICODE],
	with special attention to characters outside the ASCII range [RFC20].		with special attention to characters outside the ASCII range [RFC20].
	The methods defined here might be applicable wherever usernames or		The methods defined here might be applicable wherever usernames or
	passwords are used. However, the methods are not intended for use in		passwords are used. However, the methods are not intended for use in
	preparing strings that are not usernames (e.g., email addresses and		preparing strings that are not usernames (e.g., email addresses and
	LDAP distinguished names), nor in cases where identifiers or secrets		LDAP distinguished names), nor in cases where identifiers or secrets
	are not strings (e.g., keys and certificates) or require specialized		are not strings (e.g., keys and certificates) or require specialized
	handling.		handling.
	skipping to change at page 5, line 41 ¶		skipping to change at page 5, line 41 ¶
	All code points and blocks not explicitly allowed in the PRECIS		All code points and blocks not explicitly allowed in the PRECIS
	IdentifierClass are disallowed; this includes private use characters,		IdentifierClass are disallowed; this includes private use characters,
	surrogate code points, and the other code points and blocks that were		surrogate code points, and the other code points and blocks that were
	defined as "Prohibited Output" in [RFC4013]. In addition, common		defined as "Prohibited Output" in [RFC4013]. In addition, common
	constructions such as "user@example.com" are allowed as usernames		constructions such as "user@example.com" are allowed as usernames
	under this specification, as they were under [RFC4013].		under this specification, as they were under [RFC4013].
	4.2. Preparation		4.2. Preparation
	A username MUST NOT be zero bytes in length. This rule is to be		Each userpart of a username MUST conform to the
	enforced after any normalization and mapping of code points.		"UsernameIdentifierClass" profile of the PRECIS IdentifierClass,
			which is defined as follows:
	Each userpart of a username MUST conform to the definition of the
	PRECIS IdentifierClass provided in [I-D.ietf-precis-framework], where
	the width mapping, additional mapping, case mapping, normalization,
	and directionality rules are as follows.
	1. Fullwidth and halfwidth characters MUST be mapped to their		1. The base string class is the "IdentifierClass" specified in
			[I-D.ietf-precis-framework].
			2. Fullwidth and halfwidth characters MUST be mapped to their
	decomposition equivalents.		decomposition equivalents.
			3. So-called additional mappings MAY be applied, such as those
	2. So-called additional mappings MAY be applied, such as those
	defined in [I-D.ietf-precis-mappings].		defined in [I-D.ietf-precis-mappings].
	3. Uppercase and titlecase characters SHOULD be mapped to their
	lowercase equivalents (not doing so can lead to false positives		4. Uppercase and titlecase characters might be mapped to their
	during authentication and authorization, as described in		lowercase equivalents (see Section 4.2.1 below).
	[RFC6943]).		5. Unicode Normalization Form C (NFC) MUST be applied to all
	4. Unicode Normalization Form C (NFC) MUST be applied to all
	characters.		characters.
	With regard to directionality, the "Bidi Rule" provided in [RFC5893]		With regard to directionality, the "Bidi Rule" provided in [RFC5893]
	applies.		applies.
	SASL mechanisms that directly re-use this profile MUST specify		A username MUST NOT be zero bytes in length. This rule is to be
	whether and when case mapping is to be applied to authentication		enforced after any normalization and mapping of code points.
	identifiers. SASL mechanisms SHOULD delay any case mapping to the
	last possible moment, such as when doing a lookup by username,
	username comparisons, or generating a cryptographic salt from a
	username. In keeping with RFC4422, SASL mechanisms are not to apply
	this or any other profile to authorization identifiers.
	Application protocols that use SASL (such as IMAP [RFC4616] and XMPP
	[RFC6120]) and that directly re-use this profile MUST specify whether
	case mapping is to be applied to authorization identifiers. Such
	"SASL application protocols" SHOULD delay any case mapping of
	authorization identifiers to the last possible moment, which happens
	to necessarily be on the server side. In keeping with RFC4422, SASL
	application protocols are not to apply this or any other profile to
	authentication identifiers.
	Application protoocls that do not use SASL (such as HTTP
	authentication with the Basic and Digest schemes [RFC2617]) MUST
	specify whether and when case mapping is to be applied to
	authentication identifiers and authorization identifiers. Such
	application protocols SHOULD delay any case mapping to the last
	possible moment, such as when doing a lookup by username, username
	comparisons, or generating a cryptographic salt from a username.
	In protocols that provide usernames as input to a cryptographic		In protocols that provide usernames as input to a cryptographic
	algorithm such as a hash function, the client will need to perform		algorithm such as a hash function, the client will need to perform
	proper preparation of the username before applying the algorithm,		proper preparation of the username before applying the algorithm.
	since the username is not available to the server in plaintext form.
			4.2.1. Case Mapping
			Case mapping is a matter for the application protocol, protocol
			implementation, or end deployment. In general, this document
			suggests that it is preferable to perform case mapping, since not
			doing so can lead to false positives during authentication and
			authorization (as described in [RFC6943]) and can result in confusion
			among end users given the prevalence of case mapping in many existing
			protocols and applications. However, there can be good reasons to
			not perform case mapping, such as backward compatibility with
			deployed infrastructure.
			In particular:
			o SASL mechanisms that directly re-use this profile MUST specify
			whether and when case mapping is to be applied to authentication
			identifiers. SASL mechanisms SHOULD delay any case mapping to the
			last possible moment, such as when doing a lookup by username,
			username comparisons, or generating a cryptographic salt from a
			username (if the last possible moment happens on the server, then
			decisions about case mapping can be a matter of deployment
			policy). In keeping with RFC4422, SASL mechanisms are not to
			apply this or any other profile to authorization identifiers.
			o Application protocols that use SASL (such as IMAP [RFC3501] and
			XMPP [RFC6120]) and that directly re-use this profile MUST specify
			whether case mapping is to be applied to authorization
			identifiers. Such "SASL application protocols" SHOULD delay any
			case mapping of authorization identifiers to the last possible
			moment, which happens to necessarily be on the server side (this
			enables decisions about case mapping to be a matter of deployment
			policy). In keeping with RFC4422, SASL application protocols are
			not to apply this or any other profile to authentication
			identifiers.
			o Application protocols that do not use SASL (such as HTTP
			authentication with the Basic and Digest schemes [RFC2617]) MUST
			specify whether and when case mapping is to be applied to
			authentication identifiers and authorization identifiers. Such
			"non-SASL application protocols" SHOULD delay any case mapping to
			the last possible moment, such as when doing a lookup by username,
			username comparisons, or generating a cryptographic salt from a
			username (if the last possible moment happens on the server, then
			decisions about case mapping can be a matter of deployment
			policy).
			If the specification for a SASL mechanism, SASL application protocol,
			or non-SASL application protocol specifies the handling of case
			mapping for strings that conform to the UsernameIdentifierClass, it
			MUST clearly describe whether case mapping is required, recommended,
			or optional at the level of the protocol itself, implementations
			thereof, or service deployments.
	5. Passwords		5. Passwords
	5.1. Definition		5.1. Definition
	This document specifies that a password is a string of Unicode code		This document specifies that a password is a string of Unicode code
	points [UNICODE], encoded using UTF-8 [RFC3629], and conformant to		points [UNICODE], encoded using UTF-8 [RFC3629], and conformant to
	the PRECIS FreeformClass.		the PRECIS FreeformClass.
	The syntax for a password is defined as follows using the Augmented		The syntax for a password is defined as follows using the Augmented
	Backus-Naur Form (ABNF) [RFC5234].		Backus-Naur Form (ABNF) [RFC5234].
	password = 1*(freepoint)		password = 1*(freepoint)
	skipping to change at page 7, line 27 ¶		skipping to change at page 7, line 48 ¶
	; the PRECIS "FreeformClass"		; the PRECIS "FreeformClass"
	;		;
	All code points and blocks not explicitly allowed in the PRECIS		All code points and blocks not explicitly allowed in the PRECIS
	FreeformClass are disallowed; this includes private use characters,		FreeformClass are disallowed; this includes private use characters,
	surrogate code points, and the other code points and blocks defined		surrogate code points, and the other code points and blocks defined
	as "Prohibited Output" in Section 2.3 of RFC 4013.		as "Prohibited Output" in Section 2.3 of RFC 4013.
	5.2. Preparation		5.2. Preparation
	A password MUST NOT be zero bytes in length. This rule is to be		A password MUST conform to the "PasswordFreeformClass" profile of the
	enforced after any normalization and mapping of code points.		PRECIS FreeformClass, which is defined as follows:
	A password MUST conform to the definition of the PRECIS FreeformClass
	provided in [I-D.ietf-precis-framework], where the width mapping,
	additional mapping, case mapping, normalization, and directionality
	rules are as described below.
	1. Fullwidth and halfwidth characters MUST NOT be mapped to their		1. The base string class is the "FreeformClass" specified in
			[I-D.ietf-precis-framework].
			2. Fullwidth and halfwidth characters MUST NOT be mapped to their
	decomposition equivalents.		decomposition equivalents.
	2. Any instances of non-ASCII space MUST be mapped to ASCII space		3. Any instances of non-ASCII space MUST be mapped to ASCII space
	(U+0020).		(U+0020).
	3. So-called additional mappings MAY be applied, such as those		4. So-called additional mappings MAY be applied, such as those
	defined in [I-D.ietf-precis-mappings].		defined in [I-D.ietf-precis-mappings].
	4. Uppercase and titlecase characters MUST NOT be mapped to their		5. Uppercase and titlecase characters MUST NOT be mapped to their
	lowercase equivalents.		lowercase equivalents.
	5. Unicode Normalization Form C (NFC) MUST be applied to all		6. Unicode Normalization Form C (NFC) MUST be applied to all
	characters.		characters.
	With regard to directionality, the "Bidi Rule" (defined in [RFC5893])		With regard to directionality, the "Bidi Rule" (defined in [RFC5893])
	and similar rules are unnecessary and inapplicable to passwords,		and similar rules are unnecessary and inapplicable to passwords,
	since they can reduce the range of characters that are allowed in a		since they can reduce the range of characters that are allowed in a
	string and therefore reduce the amount of entropy that is possible in		string and therefore reduce the amount of entropy that is possible in
	a password. Furthermore, such rules are intended to minimize the		a password. Furthermore, such rules are intended to minimize the
	possibility that the same string will be displayed differently on a		possibility that the same string will be displayed differently on a
	system set for right-to-left display and a system set for left-to-		system set for right-to-left display and a system set for left-to-
	right display; however, passwords are typically not displayed at all		right display; however, passwords are typically not displayed at all
	and are rarely meant to be interoperable across different systems in		and are rarely meant to be interoperable across different systems in
	the way that non-secret strings like domain names and usernames are.		the way that non-secret strings like domain names and usernames are.
			A password MUST NOT be zero bytes in length. This rule is to be
			enforced after any normalization and mapping of code points.
	In protocols that provide passwords as input to a cryptographic		In protocols that provide passwords as input to a cryptographic
	algorithm such as a hash function, the client will need to perform		algorithm such as a hash function, the client will need to perform
	proper preparation of the password before applying the algorithm,		proper preparation of the password before applying the algorithm,
	since the password is not available to the server in plaintext form.		since the password is not available to the server in plaintext form.
	6. Migration		6. Migration
	The rules defined in this specification differ slightly from those		The rules defined in this specification differ slightly from those
	defined by the SASLprep specification [RFC4013]. The following		defined by the SASLprep specification [RFC4013]. The following
	sections describe these differences, along with their implications		sections describe these differences, along with their implications
	skipping to change at page 9, line 5 ¶		skipping to change at page 9, line 29 ¶
	is compatibility equivalent to U+0066 LATIN SMALL LETTER F and		is compatibility equivalent to U+0066 LATIN SMALL LETTER F and
	U+0069 LATIN SMALL LETTER I. Under SASLprep, the use of NFKC also		U+0069 LATIN SMALL LETTER I. Under SASLprep, the use of NFKC also
	handled the mapping of fullwidth and halfwidth code points to		handled the mapping of fullwidth and halfwidth code points to
	their decomposition equivalents (see [I-D.ietf-precis-mappings]).		their decomposition equivalents (see [I-D.ietf-precis-mappings]).
	Although it is expected that code points with compatibility		Although it is expected that code points with compatibility
	equivalents are rare in existing usernames, for migration purposes		equivalents are rare in existing usernames, for migration purposes
	deployments might want to search their database of usernames for		deployments might want to search their database of usernames for
	Unicode code points with compatibility equivalents and map those		Unicode code points with compatibility equivalents and map those
	code points to their compatibility equivalents.		code points to their compatibility equivalents.
	o SASLprep mapped non-ASCII spaces to ASCII space (U+0020), whereas
	the PRECIS IdentifierClass entirely disallows non-ASCII spaces.
	The non-ASCII space characters are U+00A0 NO-BREAK SPACE, U+1680
	OGHAM SPACE MARK, U+180E MONGOLIAN VOWEL SEPARATOR, U+2000 EN QUAD
	through U+200A HAIR SPACE, U+202F NARROW NO-BREAK SPACE, U+205F
	MEDIUM MATHEMATICAL SPACE, and U+3000 IDEOGRAPHIC SPACE. For
	migration purposes, deployments might want to convert non-ASCII
	space characters to ASCII space in usernames.
	o SASLprep mapped the "characters commonly mapped to nothing" from		o SASLprep mapped the "characters commonly mapped to nothing" from
	Appendix B.1 of [RFC3454]) to nothing, whereas the PRECIS		Appendix B.1 of [RFC3454]) to nothing, whereas the PRECIS
	IdentifierClass entirely disallows most of these characters, which		IdentifierClass entirely disallows most of these characters, which
	correspond to the code points from the "M" category defined under		correspond to the code points from the "M" category defined under
	Section 6.13 of [I-D.ietf-precis-framework] (with the exception of		Section 6.13 of [I-D.ietf-precis-framework] (with the exception of
	U+1806 MONGOLIAN TODO SOFT HYPHEN, which was "commonly mapped to		U+1806 MONGOLIAN TODO SOFT HYPHEN, which was "commonly mapped to
	nothing" in Unicode 3.2 but at the time of this writing does not		nothing" in Unicode 3.2 but at the time of this writing does not
	have a derived property of Default_Ignorable_Code_Point in Unicode		have a derived property of Default_Ignorable_Code_Point in Unicode
	6.2). For migration purposes, deployments might want to remove		6.2). For migration purposes, deployments might want to remove
	code points contained in the PRECIS "M" category from usernames.		code points contained in the PRECIS "M" category from usernames.
	skipping to change at page 10, line 25 ¶		skipping to change at page 10, line 40 ¶
	Appendix B.1 of [RFC3454]) to nothing, whereas the PRECIS		Appendix B.1 of [RFC3454]) to nothing, whereas the PRECIS
	FreeformClass entirely disallows such characters, which correspond		FreeformClass entirely disallows such characters, which correspond
	to the code points from the "M" category defined under Section		to the code points from the "M" category defined under Section
	6.13 of [I-D.ietf-precis-framework] (with the exception of U+1806		6.13 of [I-D.ietf-precis-framework] (with the exception of U+1806
	MONGOLIAN TODO SOFT HYPHEN, which was commonly mapped to nothing		MONGOLIAN TODO SOFT HYPHEN, which was commonly mapped to nothing
	in Unicode 3.2 but at the time of this writing is allowed by		in Unicode 3.2 but at the time of this writing is allowed by
	Unicode 6.2). In practice, this change will probably have no		Unicode 6.2). In practice, this change will probably have no
	effect on comparison, but user-oriented software might reject such		effect on comparison, but user-oriented software might reject such
	code points instead of ignoring them during password preparation.		code points instead of ignoring them during password preparation.
	7. Security Considerations		7. IANA Considerations
	7.1. Password/Passphrase Strength		The IANA shall add the following entries to the PRECIS Profiles
			Registry.
			7.1. UsernameIdentifierClass
			Name: UsernameIdentifierClass.
			Applicability: Usernames in security and application protocols.
			Base Class: IdentifierClass.
			Replaces: The SASLprep profile of Stringprep.
			Width Mapping: Map fullwidth and halfwidth characters to their
			decomposition equivalents.
			Additional Mappings: None required or recommended.
			Case Mapping: To be defined by security or application protocols
			that use this profile.
			Normalization: NFC.
			Directionality: The "Bidi Rule" defined in RFC 5893 applies.
			Exclusions: None.
			Enforcement: To be defined by security or application protocols that
			use this profile.
			Specification: RFC XXXX. [Note to RFC Editor: please change XXXX to
			the number issued for this specification.]
			7.2. PasswordFreeformClass
			Name: PasswordFreeformClass.
			Applicability: Passwords in security and application protocols.
			Base Class: FreeformClass
			Replaces: The SASLprep profile of Stringprep.
			Width Mapping: None.
			Additional Mappings: Map non-ASCII space characters to ASCII space.
			Case Mapping: None.
			Normalization: NFC.
			Directionality: None.
			Exclusions: None.
			Enforcement: To be defined by security or application protocols that
			use this profile.
			Specification: RFC XXXX.
			8. Security Considerations
			8.1. Password/Passphrase Strength
	The ability to include a wide range of characters in passwords and		The ability to include a wide range of characters in passwords and
	passphrases can increase the potential for creating a strong password		passphrases can increase the potential for creating a strong password
	with high entropy. However, in practice, the ability to include such		with high entropy. However, in practice, the ability to include such
	characters ought to be weighed against the possible need to reproduce		characters ought to be weighed against the possible need to reproduce
	them on various devices using various input methods.		them on various devices using various input methods.
	7.2. Identifier Comparison		8.2. Identifier Comparison
	The process of comparing identifiers (such as SASL simple user names,		The process of comparing identifiers (such as SASL simple user names,
	authentication identifiers, and authorization identifiers) can lead		authentication identifiers, and authorization identifiers) can lead
	to either false negatives or false positives, both of which have		to either false negatives or false positives, both of which have
	security implications. A more detailed discussion can be found in		security implications. A more detailed discussion can be found in
	[RFC6943].		[RFC6943].
	7.3. Reuse of PRECIS		8.3. Reuse of PRECIS
	The security considerations described in [I-D.ietf-precis-framework]		The security considerations described in [I-D.ietf-precis-framework]
	apply to the "IdentifierClass" and "FreeformClass" base string		apply to the "IdentifierClass" and "FreeformClass" base string
	classes used in this document for usernames and passwords,		classes used in this document for usernames and passwords,
	respectively.		respectively.
	7.4. Reuse of Unicode		8.4. Reuse of Unicode
	The security considerations described in [UTR39] apply to the use of		The security considerations described in [UTS39] apply to the use of
	Unicode characters in usernames and passwords.		Unicode characters in usernames and passwords.
	8. IANA Considerations
	[Note to RFC Editor: please change XXXX to the number issued for this
	specification.]
	8.1. Use of IdentifierClass
	The IANA shall add an entry to the PRECIS Usage Registry for reuse of
	the PRECIS IdentifierClass, as follows:
	Applicability: Usernames in security and application protocols.
	Base Class: IdentifierClass.
	Subclass: No.
	Replaces: The SASLprep profile of Stringprep.
	Width Mapping: Map fullwidth and halfwidth characters to their
	decomposition equivalents.
	Additional Mappings: None.
	Case Mapping: Not recommended, but to be defined by application
	protocols that use this profile.
	Normalization: NFC.
	Directionality: The "Bidi Rule" defined in RFC 5893 applies.
	Specification: RFC XXXX.
	8.2. Use of FreeformClass
	The IANA shall add an entry to the PRECIS Usage Registry for reuse of
	the PRECIS FreeformClass, as follows:
	Applicability: Passwords in security and application protocols.
	Base Class: FreeformClass
	Subclass: No.
	Replaces: The SASLprep profile of Stringprep.
	Width Mapping: None.
	Additional Mappings: Map non-ASCII space characters to ASCII space.
	Case Mapping: None.
	Normalization: NFC.
	Directionality: None.
	Specification: RFC XXXX.
	9. References		9. References
	9.1. Normative References		9.1. Normative References
	[I-D.ietf-precis-framework]		[I-D.ietf-precis-framework]
	Saint-Andre, P. and M. Blanchet, "Precis Framework:		Saint-Andre, P. and M. Blanchet, "Precis Framework:
	Handling Internationalized Strings in Protocols",		Handling Internationalized Strings in Protocols",
	draft-ietf-precis-framework-09 (work in progress),		draft-ietf-precis-framework-10 (work in progress),
	July 2013.		October 2013.
	[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, March 1997.		Requirement Levels", BCP 14, RFC 2119, March 1997.
	[RFC3629] Yergeau, F., "UTF-8, a transformation format of ISO		[RFC3629] Yergeau, F., "UTF-8, a transformation format of ISO
	10646", STD 63, RFC 3629, November 2003.		10646", STD 63, RFC 3629, November 2003.
	[RFC5234] Crocker, D. and P. Overell, "Augmented BNF for Syntax		[RFC5234] Crocker, D. and P. Overell, "Augmented BNF for Syntax
	Specifications: ABNF", STD 68, RFC 5234, January 2008.		Specifications: ABNF", STD 68, RFC 5234, January 2008.
	[UNICODE] The Unicode Consortium, "The Unicode Standard, Version		[UNICODE] The Unicode Consortium, "The Unicode Standard, Version
	6.1", 2012,		6.1", 2012,
	<http://www.unicode.org/versions/Unicode6.1.0/>.		<http://www.unicode.org/versions/Unicode6.1.0/>.
	9.2. Informative References		9.2. Informative References
	[I-D.ietf-precis-mappings]		[I-D.ietf-precis-mappings]
	YONEYA, Y. and T. NEMOTO, "Mapping characters for PRECIS		Yoneya, Y. and T. NEMOTO, "Mapping characters for PRECIS
	classes", draft-ietf-precis-mappings-02 (work in		classes", draft-ietf-precis-mappings-04 (work in
	progress), May 2013.		progress), October 2013.
	[RFC20] Cerf, V., "ASCII format for network interchange", RFC 20,		[RFC20] Cerf, V., "ASCII format for network interchange", RFC 20,
	October 1969.		October 1969.
	[RFC2617] Franks, J., Hallam-Baker, P., Hostetler, J., Lawrence, S.,		[RFC2617] Franks, J., Hallam-Baker, P., Hostetler, J., Lawrence, S.,
	Leach, P., Luotonen, A., and L. Stewart, "HTTP		Leach, P., Luotonen, A., and L. Stewart, "HTTP
	Authentication: Basic and Digest Access Authentication",		Authentication: Basic and Digest Access Authentication",
	RFC 2617, June 1999.		RFC 2617, June 1999.
	[RFC3454] Hoffman, P. and M. Blanchet, "Preparation of		[RFC3454] Hoffman, P. and M. Blanchet, "Preparation of
	Internationalized Strings ("stringprep")", RFC 3454,		Internationalized Strings ("stringprep")", RFC 3454,
	December 2002.		December 2002.
			[RFC3501] Crispin, M., "INTERNET MESSAGE ACCESS PROTOCOL - VERSION
			4rev1", RFC 3501, March 2003.
	[RFC4013] Zeilenga, K., "SASLprep: Stringprep Profile for User Names		[RFC4013] Zeilenga, K., "SASLprep: Stringprep Profile for User Names
	and Passwords", RFC 4013, February 2005.		and Passwords", RFC 4013, February 2005.
	[RFC4422] Melnikov, A., Ed. and K. Zeilenga, Ed., "Simple		[RFC4422] Melnikov, A., Ed. and K. Zeilenga, Ed., "Simple
	Authentication and Security Layer (SASL)", RFC 4422,		Authentication and Security Layer (SASL)", RFC 4422,
	June 2006.		June 2006.
	[RFC4616] Zeilenga, K., "The PLAIN Simple Authentication and		[RFC4616] Zeilenga, K., "The PLAIN Simple Authentication and
	Security Layer (SASL) Mechanism", RFC 4616, August 2006.		Security Layer (SASL) Mechanism", RFC 4616, August 2006.
	skipping to change at page 13, line 35 ¶		skipping to change at page 14, line 9 ¶
	[RFC6120] Saint-Andre, P., "Extensible Messaging and Presence		[RFC6120] Saint-Andre, P., "Extensible Messaging and Presence
	Protocol (XMPP): Core", RFC 6120, March 2011.		Protocol (XMPP): Core", RFC 6120, March 2011.
	[RFC6365] Hoffman, P. and J. Klensin, "Terminology Used in		[RFC6365] Hoffman, P. and J. Klensin, "Terminology Used in
	Internationalization in the IETF", BCP 166, RFC 6365,		Internationalization in the IETF", BCP 166, RFC 6365,
	September 2011.		September 2011.
	[RFC6943] Thaler, D., "Issues in Identifier Comparison for Security		[RFC6943] Thaler, D., "Issues in Identifier Comparison for Security
	Purposes", RFC 6943, May 2013.		Purposes", RFC 6943, May 2013.
	[UTR39] The Unicode Consortium, "Unicode Technical Report #39:		[UTS39] The Unicode Consortium, "Unicode Technical Standard #39:
	Unicode Security Mechanisms", August 2010,		Unicode Security Mechanisms", July 2012,
	<http://unicode.org/reports/tr39/>.		<http://unicode.org/reports/tr39/>.
	Appendix A. Differences from RFC 4013		Appendix A. Differences from RFC 4013
	This document builds upon the PRECIS framework defined in		This document builds upon the PRECIS framework defined in
	[I-D.ietf-precis-framework], which differs fundamentally from the		[I-D.ietf-precis-framework], which differs fundamentally from the
	stringprep technology [RFC3454] used in SASLprep [RFC4013]. The		stringprep technology [RFC3454] used in SASLprep [RFC4013]. The
	primary difference is that stringprep profiles allowed all characters		primary difference is that stringprep profiles allowed all characters
	except those which were explicitly disallowed, whereas PRECIS		except those which were explicitly disallowed, whereas PRECIS
	profiles disallow all characters except those which are explicitly		profiles disallow all characters except those which are explicitly
	skipping to change at page 14, line 24 ¶		skipping to change at page 14, line 45 ¶
	normalization form to NFC (from NFKC).		normalization form to NFC (from NFKC).
	o Some Unicode code points that were mapped to nothing in RFC 4013		o Some Unicode code points that were mapped to nothing in RFC 4013
	are simply disallowed by PRECIS.		are simply disallowed by PRECIS.
	Appendix B. Acknowledgements		Appendix B. Acknowledgements
	The following individuals provided helpful feedback on this document:		The following individuals provided helpful feedback on this document:
	Marc Blanchet, Alan DeKok, Joe Hildebrand, Jeffrey Hutzelman, Simon		Marc Blanchet, Alan DeKok, Joe Hildebrand, Jeffrey Hutzelman, Simon
	Josefsson, Jonathan Lennox, Matt Miller, Chris Newman, Yutaka OIWA,		Josefsson, Jonathan Lennox, Matt Miller, Chris Newman, Yutaka OIWA,
	Pete Resnick, Andrew Sullivan, and Nico Williams (Nico in particular		Pete Resnick, Andrew Sullivan, and Nico Williams (Nico in particular
	provided text that was used in Section 2.2). Thanks also to Yoshiro		provided text that was used in Section 4.2.1). Thanks also to
	YONEYA and Takahiro NEMOTO for implementation feedback.		Yoshiro YONEYA and Takahiro NEMOTO for implementation feedback.
	This document borrows some text from [RFC4013] and [RFC6120].		This document borrows some text from [RFC4013] and [RFC6120].
	Authors' Addresses		Authors' Addresses
	Peter Saint-Andre		Peter Saint-Andre
	Cisco Systems, Inc.		Cisco Systems, Inc.
	1899 Wynkoop Street, Suite 600		1899 Wynkoop Street, Suite 600
	Denver, CO 80202		Denver, CO 80202
	USA		USA
End of changes. 37 change blocks.
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