draft-ietf-lamps-eai-addresses-13.txt		draft-ietf-lamps-eai-addresses-14.txt
	LAMPS A. Melnikov, Ed.		LAMPS A. Melnikov, Ed.
	Internet-Draft Isode Ltd		Internet-Draft Isode Ltd
	Intended status: Standards Track W. Chuang, Ed.		Intended status: Standards Track W. Chuang, Ed.
	Expires: March 3, 2018 Google, Inc.		Expires: March 7, 2018 Google, Inc.
	August 30, 2017		September 3, 2017
	Internationalized Email Addresses in X.509 certificates		Internationalized Email Addresses in X.509 certificates
	draft-ietf-lamps-eai-addresses-13		draft-ietf-lamps-eai-addresses-14
	Abstract		Abstract
	This document defines a new name form for inclusion in the otherName		This document defines a new name form for inclusion in the otherName
	field of an X.509 Subject Alternative Name and Issuer Alternative		field of an X.509 Subject Alternative Name and Issuer Alternative
	Name extension that allows a certificate subject to be associated		Name extension that allows a certificate subject to be associated
	with an Internationalized Email Address.		with an Internationalized Email Address.
	Status of This Memo		Status of This Memo
	skipping to change at page 1, line 34 ¶		skipping to change at page 1, line 34 ¶
	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 March 3, 2018.		This Internet-Draft will expire on March 7, 2018.
	Copyright Notice		Copyright Notice
	Copyright (c) 2017 IETF Trust and the persons identified as the		Copyright (c) 2017 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 20 ¶		skipping to change at page 2, line 20 ¶
	4. IDNA2008 . . . . . . . . . . . . . . . . . . . . . . . . . . 4		4. IDNA2008 . . . . . . . . . . . . . . . . . . . . . . . . . . 4
	5. Matching of Internationalized Email Addresses in X.509		5. Matching of Internationalized Email Addresses in X.509
	certificates . . . . . . . . . . . . . . . . . . . . . . . . 4		certificates . . . . . . . . . . . . . . . . . . . . . . . . 4
	6. Name constraints in path validation . . . . . . . . . . . . . 5		6. Name constraints in path validation . . . . . . . . . . . . . 5
	7. Security Considerations . . . . . . . . . . . . . . . . . . . 7		7. Security Considerations . . . . . . . . . . . . . . . . . . . 7
	8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7		8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7
	9. References . . . . . . . . . . . . . . . . . . . . . . . . . 8		9. References . . . . . . . . . . . . . . . . . . . . . . . . . 8
	9.1. Normative References . . . . . . . . . . . . . . . . . . 8		9.1. Normative References . . . . . . . . . . . . . . . . . . 8
	9.2. Informative References . . . . . . . . . . . . . . . . . 9		9.2. Informative References . . . . . . . . . . . . . . . . . 9
	Appendix A. ASN.1 Module . . . . . . . . . . . . . . . . . . . . 9		Appendix A. ASN.1 Module . . . . . . . . . . . . . . . . . . . . 9
	Appendix B. Example of SmtpUTF8Name . . . . . . . . . . . . . . 10		Appendix B. Example of SmtpUTF8Mailbox . . . . . . . . . . . . . 10
	Appendix C. Acknowledgements . . . . . . . . . . . . . . . . . . 11		Appendix C. Acknowledgements . . . . . . . . . . . . . . . . . . 11
	Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 11		Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 11
	1. Introduction		1. Introduction
	[RFC5280] defines the rfc822Name subjectAltName name type for		[RFC5280] defines the rfc822Name subjectAltName name type for
	representing [RFC5321] email addresses. The syntax of rfc822Name is		representing [RFC5321] email addresses. The syntax of rfc822Name is
	restricted to a subset of US-ASCII characters and thus can't be used		restricted to a subset of US-ASCII characters and thus can't be used
	to represent Internationalized Email addresses [RFC6531]. This		to represent Internationalized Email addresses [RFC6531]. This
	document defines a new otherName variant to represent		document defines a new otherName variant to represent
	skipping to change at page 2, line 48 ¶		skipping to change at page 2, line 48 ¶
	"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this		"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
	document are to be interpreted as described in [RFC2119].		document are to be interpreted as described in [RFC2119].
	The formal syntax uses the Augmented Backus-Naur Form (ABNF)		The formal syntax uses the Augmented Backus-Naur Form (ABNF)
	[RFC5234] notation.		[RFC5234] notation.
	3. Name Definitions		3. Name Definitions
	The GeneralName structure is defined in [RFC5280], and supports many		The GeneralName structure is defined in [RFC5280], and supports many
	different name forms including otherName for extensibility. This		different name forms including otherName for extensibility. This
	section specifies the SmtpUTF8Name name form of otherName, so that		section specifies the SmtpUTF8Mailbox name form of otherName, so that
	Internationalized Email addresses can appear in the subjectAltName of		Internationalized Email addresses can appear in the subjectAltName of
	a certificate, the issuerAltName of a certificate, or anywhere else		a certificate, the issuerAltName of a certificate, or anywhere else
	that GeneralName is used.		that GeneralName is used.
	id-on-SmtpUTF8Name OBJECT IDENTIFIER ::= { id-on 9 }		id-on-SmtpUTF8Mailbox OBJECT IDENTIFIER ::= { id-on 9 }
	SmtpUTF8Name ::= UTF8String (SIZE (1..MAX))		SmtpUTF8Mailbox ::= UTF8String (SIZE (1..MAX))
	-- SmtpUTF8Name conforms to Mailbox as specified		-- SmtpUTF8Mailbox conforms to Mailbox as specified
	-- in Section 3.3 of RFC 6531.		-- in Section 3.3 of RFC 6531.
	When the subjectAltName (or issuerAltName) extension contains an		When the subjectAltName (or issuerAltName) extension contains an
	Internationalized Email address with a non-ASCII local-part, the		Internationalized Email address with a non-ASCII local-part, the
	address MUST be stored in the SmtpUTF8Name name form of otherName.		address MUST be stored in the SmtpUTF8Mailbox name form of otherName.
	The format of SmtpUTF8Name is defined as the ABNF rule		The format of SmtpUTF8Mailbox is defined as the ABNF rule
	SmtpUTF8Mailbox. SmtpUTF8Mailbox is a modified version of the		SmtpUTF8Mailbox. SmtpUTF8Mailbox is a modified version of the
	Internationalized Mailbox which was defined in Section 3.3 of		Internationalized Mailbox which was defined in Section 3.3 of
	[RFC6531] which was itself derived from SMTP Mailbox from		[RFC6531] which was itself derived from SMTP Mailbox from
	Section 4.1.2 of [RFC5321]. [RFC6531] defines the following ABNF		Section 4.1.2 of [RFC5321]. [RFC6531] defines the following ABNF
	rules for Mailbox whose parts are modified for internationalization:		rules for Mailbox whose parts are modified for internationalization:
	<Local-part>, <Dot-string>, <Quoted-string>, <QcontentSMTP>,		<Local-part>, <Dot-string>, <Quoted-string>, <QcontentSMTP>,
	<Domain>, and <Atom>. In particular, <Local-part> was updated to		<Domain>, and <Atom>. In particular, <Local-part> was updated to
	also support UTF8-non-ascii. UTF8-non-ascii was described by		also support UTF8-non-ascii. UTF8-non-ascii was described by
	Section 3.1 of [RFC6532]. Also, domain was extended to support		Section 3.1 of [RFC6532]. Also, domain was extended to support
	U-labels, as defined in [RFC5890].		U-labels, as defined in [RFC5890].
	skipping to change at page 3, line 40 ¶		skipping to change at page 3, line 40 ¶
	need to determine which label encoding A- or U-label is present in		need to determine which label encoding A- or U-label is present in
	the Domain. As per Section 2.3.2.1 of [RFC5890], U-label are encoded		the Domain. As per Section 2.3.2.1 of [RFC5890], U-label are encoded
	as UTF-8 [RFC3629] in Normalization Form C and other properties		as UTF-8 [RFC3629] in Normalization Form C and other properties
	specified there. In SmtpUTF8Mailbox, domain labels that solely use		specified there. In SmtpUTF8Mailbox, domain labels that solely use
	ASCII characters (meaning not A- nor U-labels) SHALL use NR-LDH		ASCII characters (meaning not A- nor U-labels) SHALL use NR-LDH
	restrictions as specified by Section 2.3.1 of [RFC5890] and SHALL be		restrictions as specified by Section 2.3.1 of [RFC5890] and SHALL be
	restricted to lower case letters. NR-LDH stands for "Non-Reserved		restricted to lower case letters. NR-LDH stands for "Non-Reserved
	Letters Digits Hyphen" and is the set of LDH labels that do not have		Letters Digits Hyphen" and is the set of LDH labels that do not have
	"--" characters in the third and forth character position, which		"--" characters in the third and forth character position, which
	excludes "tagged domain names" such as A-labels. Consistent with the		excludes "tagged domain names" such as A-labels. Consistent with the
	treatment of rfc822Name in [RFC5280], SmtpUTF8Name is an envelope		treatment of rfc822Name in [RFC5280], SmtpUTF8Mailbox is an envelope
	<Mailbox> and has no phrase (such as a common name) before it, has no		<Mailbox> and has no phrase (such as a common name) before it, has no
	comment (text surrounded in parentheses) after it, and is not		comment (text surrounded in parentheses) after it, and is not
	surrounded by "<" and ">".		surrounded by "<" and ">".
	Due to operational reasons to be described shortly and name		Due to operational reasons to be described shortly and name
	constraint compatibility reasons described in Section 6, SmtpUTF8Name		constraint compatibility reasons described in Section 6,
	subjectAltName MUST only be used when the local part of the email		SmtpUTF8Mailbox subjectAltName MUST only be used when the local part
	address contains contains non-ASCII characters. When the local-part		of the email address contains contains non-ASCII characters. When
	is ASCII, rfc822Name subjectAltName MUST be used instead of		the local-part is ASCII, rfc822Name subjectAltName MUST be used
	SmtpUTF8Name. This is compatible with legacy software that supports		instead of SmtpUTF8Mailbox. This is compatible with legacy software
	only rfc822Name (and not SmtpUTF8Name).		that supports only rfc822Name (and not SmtpUTF8Mailbox).
	SmtpUTF8Name is encoded as UTF8String. The UTF8String encoding MUST		SmtpUTF8Mailbox is encoded as UTF8String. The UTF8String encoding
	NOT contain a Byte-Order- Mark (BOM) [RFC3629] to aid consistency		MUST NOT contain a Byte-Order- Mark (BOM) [RFC3629] to aid
	across implementations particularly for comparison.		consistency across implementations particularly for comparison.
	4. IDNA2008		4. IDNA2008
	To facilitate comparison between email addresses, all email address		To facilitate comparison between email addresses, all email address
	domains in X.509 certificates MUST conform to IDNA2008 [RFC5890] (and		domains in X.509 certificates MUST conform to IDNA2008 [RFC5890] (and
	avoids any "mappings" mentioned in that document). Use of non-		avoids any "mappings" mentioned in that document). Use of non-
	conforming email address domains introduces the possibility of		conforming email address domains introduces the possibility of
	conversion errors between alternate forms. This applies to		conversion errors between alternate forms. This applies to
	SmtpUTF8Name and rfc822Name in subjectAltName, issuerAltName and		SmtpUTF8Mailbox and rfc822Name in subjectAltName, issuerAltName and
	anywhere else that these are used.		anywhere else that these are used.
	5. Matching of Internationalized Email Addresses in X.509 certificates		5. Matching of Internationalized Email Addresses in X.509 certificates
	In equivalence comparison with SmtpUTF8Name, there may be some setup		In equivalence comparison with SmtpUTF8Mailbox, there may be some
	work on one or both inputs depending of whether the input is already		setup work on one or both inputs depending of whether the input is
	in comparison form. Comparing SmtpUTF8Names consists of a domain		already in comparison form. Comparing SmtpUTF8Mailboxs consists of a
	part step and a local-part step. The comparison form for local-parts		domain part step and a local-part step. The comparison form for
	is always UTF-8. The comparison form for domain parts depends on		local-parts is always UTF-8. The comparison form for domain parts
	context. While some contexts such as certificate path validation in		depends on context. While some contexts such as certificate path
	[RFC5280] specify transforming domain to A-label (Section 7.5 and 7.2		validation in [RFC5280] specify transforming domain to A-label
	in [RFC5280] as updated by [ID-lamps-rfc5280-i18n-update]), this		(Section 7.5 and 7.2 in [RFC5280] as updated by
	document RECOMMENDS transforming to UTF-8 U-label instead. This		[ID-lamps-rfc5280-i18n-update]), this document recommends
	reduces the likelihood of errors by reducing conversions as more		transforming to UTF-8 U-label instead. This reduces the likelihood
	implementations natively support U-label domains.		of errors by reducing conversions as more implementations natively
			support U-label domains.
	Comparison of two SmtpUTF8Name is straightforward with no setup work		Comparison of two SmtpUTF8Mailbox is straightforward with no setup
	needed. They are considered equivalent if there is an exact octet-		work needed. They are considered equivalent if there is an exact
	for-octet match. Comparison with email addresses such as		octet-for-octet match. Comparison with email addresses such as
	Internationalized email address or rfc822Name requires additional		Internationalized email address or rfc822Name requires additional
	setup steps for domain part and local-part. The initial preparation		setup steps for domain part and local-part. The initial preparation
	for the email addresses is to remove any phrases or comments, as well		for the email addresses is to remove any phrases or comments, as well
	as "<" and ">" present. This document calls for comparison of domain		as "<" and ">" present. This document calls for comparison of domain
	labels that include non-ASCII characters be transformed to U-label if		labels that include non-ASCII characters be transformed to U-label if
	not already in that form. The first step is to detect use of the		not already in that form. The first step is to detect use of the
	A-label by using Section 5.1 of [RFC5891]. Next if necessary,		A-label by using Section 5.1 of [RFC5891]. Next if necessary,
	transform any A-labels to U-labels Unicode as specified in		transform any A-labels to U-labels Unicode as specified in
	Section 5.2 of [RFC5891]. Finally if necessary convert the Unicode		Section 5.2 of [RFC5891]. Finally if necessary convert the Unicode
	to UTF-8 as specified in Section 3 of [RFC3629]. For ASCII NR-LDH		to UTF-8 as specified in Section 3 of [RFC3629]. For ASCII NR-LDH
	skipping to change at page 5, line 18 ¶		skipping to change at page 5, line 19 ¶
	To summarize non-normatively, the comparison steps including setup		To summarize non-normatively, the comparison steps including setup
	are:		are:
	1. If the domain contains A-labels, transform them to U-labels.		1. If the domain contains A-labels, transform them to U-labels.
	2. If the domain contains ASCII NR-LDH labels, lowercase them.		2. If the domain contains ASCII NR-LDH labels, lowercase them.
	3. Compare strings octet-for-octet for equivalence.		3. Compare strings octet-for-octet for equivalence.
	This specification expressly does not define any wildcard characters		This specification expressly does not define any wildcard characters
	and SmtpUTF8Name comparison implementations MUST NOT interpret any		and SmtpUTF8Mailbox comparison implementations MUST NOT interpret any
	character as wildcards. Instead, to specify multiple email addresses		character as wildcards. Instead, to specify multiple email addresses
	through SmtpUTF8Name, the certificate MUST use multiple		through SmtpUTF8Mailbox, the certificate MUST use multiple
	subjectAltNames or issuerAltNames to explicitly carry any additional		subjectAltNames or issuerAltNames to explicitly carry any additional
	email addresses.		email addresses.
	6. Name constraints in path validation		6. Name constraints in path validation
	This section updates Section 4.2.1.10 of [RFC5280] to extend		This section updates Section 4.2.1.10 of [RFC5280] to extend
	rfc822Name name constraints to SmtpUTF8Name subjectAltNames. A		rfc822Name name constraints to SmtpUTF8Mailbox subjectAltNames. A
	SmtpUTF8Name aware path validators will apply name constraint		SmtpUTF8Mailbox aware path validators will apply name constraint
	comparison to the subject distinguished name and both forms of		comparison to the subject distinguished name and both forms of
	subject alternative name rfc822Name and SmtpUTF8Name.		subject alternative name rfc822Name and SmtpUTF8Mailbox.
	Both rfc822Name and SmtpUTF8Name subject alternative names represent		Both rfc822Name and SmtpUTF8Mailbox subject alternative names
	the same underlying email address namespace. Since legacy CAs		represent the same underlying email address namespace. Since legacy
	constrained to issue certificates for a specific set of domains would		CAs constrained to issue certificates for a specific set of domains
	lack corresponding UTF-8 constraints, [ID-lamps-rfc5280-i18n-update]		would lack corresponding UTF-8 constraints,
	updates modifies and extends rfc822Name name constraints defined in		[ID-lamps-rfc5280-i18n-update] updates modifies and extends
	[RFC5280] to cover SmtpUTF8Name subject alternative names. This		rfc822Name name constraints defined in [RFC5280] to cover
	ensures that the introduction of SmtpUTF8Name does not violate		SmtpUTF8Mailbox subject alternative names. This ensures that the
	existing name constraints. Since it is not valid to include non-		introduction of SmtpUTF8Mailbox does not violate existing name
	ASCII UTF-8 characters in the local-part of rfc822Name name		constraints. Since it is not valid to include non-ASCII UTF-8
	constraints, and since name constraints that include a local-part are		characters in the local-part of rfc822Name name constraints, and
	rarely, if at all, used in practice, name constraints updated in		since name constraints that include a local-part are rarely, if at
			all, used in practice, name constraints updated in
	[ID-lamps-rfc5280-i18n-update] admit the forms that represent all		[ID-lamps-rfc5280-i18n-update] admit the forms that represent all
	addresses at a host or all mailboxes in a domain, and deprecates		addresses at a host or all mailboxes in a domain, and deprecates
	rfc822Name name constraints that represent a particular mailbox.		rfc822Name name constraints that represent a particular mailbox.
	That is, rfc822Name constraints with a local-part SHOULD NOT be used.		That is, rfc822Name constraints with a local-part SHOULD NOT be used.
	Constraint comparison with SmtpUTF8Name subjectAltName starts with		Constraint comparison with SmtpUTF8Mailbox subjectAltName starts with
	the setup steps defined by Section 5. Setup converts the inputs of		the setup steps defined by Section 5. Setup converts the inputs of
	the comparison which is one of a subject distinguished name or a		the comparison which is one of a subject distinguished name or a
	rfc822Name or SmtpUTF8Name subjectAltName, and one of a rfc822Name		rfc822Name or SmtpUTF8Mailbox subjectAltName, and one of a rfc822Name
	name constraint, to constraint comparison form. For rfc822Name name		name constraint, to constraint comparison form. For rfc822Name name
	constraint, this will convert any domain A-labels to U-labels. For		constraint, this will convert any domain A-labels to U-labels. For
	both the name constraint and the subject, this will lower case any		both the name constraint and the subject, this will lower case any
	domain NR-LDH labels. Strip the local-part and "@" separator from		domain NR-LDH labels. Strip the local-part and "@" separator from
	each rfc822Name and SmtpUTF8Name, leaving just the domain-part.		each rfc822Name and SmtpUTF8Mailbox, leaving just the domain-part.
	After setup, this follows the comparison steps defined in 4.2.1.10 of		After setup, this follows the comparison steps defined in 4.2.1.10 of
	[RFC5280] as follows. If the resulting name constraint domain starts		[RFC5280] as follows. If the resulting name constraint domain starts
	with a "." character, then for the name constraint to match, a suffix		with a "." character, then for the name constraint to match, a suffix
	of the resulting subject alternative name domain MUST match the name		of the resulting subject alternative name domain MUST match the name
	constraint (including the leading ".") octet for octet. If the		constraint (including the leading ".") octet for octet. If the
	resulting name constraint domain does not start with a "." character,		resulting name constraint domain does not start with a "." character,
	then for the name constraint to match, the entire resulting subject		then for the name constraint to match, the entire resulting subject
	alternative name domain MUST match the name constraint octet for		alternative name domain MUST match the name constraint octet for
	octet.		octet.
	Certificate Authorities that wish to issue CA certificates with email		Certificate Authorities that wish to issue CA certificates with email
	address name constraint MUST use rfc822Name subject alternative names		address name constraint MUST use rfc822Name subject alternative names
	only. These MUST be IDNA2008 conformant names with no mappings, and		only. These MUST be IDNA2008 conformant names with no mappings, and
	with non-ASCII domains encoded in A-labels only.		with non-ASCII domains encoded in A-labels only.
	The name constraint requirement with SmtpUTF8Name subject alternative		The name constraint requirement with SmtpUTF8Mailbox subject
	name is illustrated in the non-normative diagram Figure 1. The first		alternative name is illustrated in the non-normative diagram
	example (1) illustrates a permitted rfc822Name ASCII only hostname		Figure 1. The first example (1) illustrates a permitted rfc822Name
	name constraint, and the corresponding valid rfc822Name		ASCII only hostname name constraint, and the corresponding valid
	subjectAltName and SmtpUTF8Name subjectAltName email addresses. The		rfc822Name subjectAltName and SmtpUTF8Mailbox subjectAltName email
	second example (2) illustrates a permitted rfc822Name hostname name		addresses. The second example (2) illustrates a permitted rfc822Name
	constraint with A-label, and the corresponding valid rfc822Name		hostname name constraint with A-label, and the corresponding valid
	subjectAltName and SmtpUTF8Name subjectAltName email addresses. Note		rfc822Name subjectAltName and SmtpUTF8Mailbox subjectAltName email
	that an email address with ASCII only local-part is encoded as		addresses. Note that an email address with ASCII only local-part is
	rfc822Name despite also having unicode present in the domain.		encoded as rfc822Name despite also having unicode present in the
			domain.
	+-------------------------------------------------------------------+		+-------------------------------------------------------------------+
	| Root CA Cert |		| Root CA Cert |
	+-------------------------------------------------------------------+		+-------------------------------------------------------------------+
	|		|
	v		v
	+-------------------------------------------------------------------+		+-------------------------------------------------------------------+
	| Intermediate CA Cert |		| Intermediate CA Cert |
	| Permitted |		| Permitted |
	| rfc822Name: elementary.school.example.com (1) |		| rfc822Name: elementary.school.example.com (1) |
	| |		| |
	| rfc822Name: xn--pss25c.example.com (2) |		| rfc822Name: xn--pss25c.example.com (2) |
	| |		| |
	+-------------------------------------------------------------------+		+-------------------------------------------------------------------+
	|		|
	v		v
	+-------------------------------------------------------------------+		+-------------------------------------------------------------------+
	| Entity Cert (w/explicitly permitted subjects) |		| Entity Cert (w/explicitly permitted subjects) |
	| SubjectAltName Extension |		| SubjectAltName Extension |
	| rfc822Name: student@elemenary.school.example.com (1) |		| rfc822Name: student@elemenary.school.example.com (1) |
	| SmtpUTF8Name: u+5B66u+751F@elementary.school.example.com (1) |		| SmtpUTF8Mailbox: u+5B66u+751F@elementary.school.example.com |
			| (1) |
	| |		| |
	| rfc822Name: student@xn--pss25c.example.com (2) |		| rfc822Name: student@xn--pss25c.example.com (2) |
	| SmtpUTF8Name: u+533Bu+751F@u+5927u+5B66.example.com (2) |		| SmtpUTF8Mailbox: u+533Bu+751F@u+5927u+5B66.example.com (2) |
	| |		| |
	+-------------------------------------------------------------------+		+-------------------------------------------------------------------+
	Name constraints with SmtpUTF8Name and rfc822Name		Name constraints with SmtpUTF8Name and rfc822Name
	Figure 1		Figure 1
	7. Security Considerations		7. Security Considerations
	Use of SmtpUTF8Name for certificate subjectAltName (and		Use of SmtpUTF8Mailbox for certificate subjectAltName (and
	issuerAltName) will incur many of the same security considerations as		issuerAltName) will incur many of the same security considerations as
	in Section 8 in [RFC5280], but introduces a new issue by permitting		in Section 8 in [RFC5280], but introduces a new issue by permitting
	non-ASCII characters in the email address local-part. This issue, as		non-ASCII characters in the email address local-part. This issue, as
	mentioned in Section 4.4 of [RFC5890] and in Section 4 of [RFC6532],		mentioned in Section 4.4 of [RFC5890] and in Section 4 of [RFC6532],
	is that use of Unicode introduces the risk of visually similar and		is that use of Unicode introduces the risk of visually similar and
	identical characters which can be exploited to deceive the recipient.		identical characters which can be exploited to deceive the recipient.
	The former document references some means to mitigate against these		The former document references some means to mitigate against these
	attacks.		attacks.
	8. IANA Considerations		8. IANA Considerations
	In Section 3 and the ASN.1 module identifier defined in Appendix A.		In Section 3 and the ASN.1 module identifier defined in Appendix A.
	IANA is kindly requested to make the following assignments for:		IANA is kindly requested to make the following assignments for:
	The LAMPS-EaiAddresses-2016 ASN.1 module in the "SMI Security for		The LAMPS-EaiAddresses-2016 ASN.1 module in the "SMI Security for
	PKIX Module Identifier" registry (1.3.6.1.5.5.7.0).		PKIX Module Identifier" registry (1.3.6.1.5.5.7.0).
	The SmtpUTF8Name otherName in the "PKIX Other Name Forms" registry		The SmtpUTF8Mailbox otherName in the "PKIX Other Name Forms"
	(1.3.6.1.5.5.7.8).		registry (1.3.6.1.5.5.7.8).
	9. References		9. References
	9.1. Normative References		9.1. Normative References
	[ID-lamps-rfc5280-i18n-update]		[ID-lamps-rfc5280-i18n-update]
	Housley, R., "Internationalization Updates to RFC 5280",		Housley, R., "Internationalization Updates to RFC 5280",
	June 2017, <https://datatracker.ietf.org/doc/draft-		June 2017, <https://datatracker.ietf.org/doc/draft-
	housley-rfc5280-i18n-update/>.		housley-rfc5280-i18n-update/>.
	skipping to change at page 9, line 26 ¶		skipping to change at page 9, line 26 ¶
	9.2. Informative References		9.2. Informative References
	[RFC5912] Hoffman, P. and J. Schaad, "New ASN.1 Modules for the		[RFC5912] Hoffman, P. and J. Schaad, "New ASN.1 Modules for the
	Public Key Infrastructure Using X.509 (PKIX)", RFC 5912,		Public Key Infrastructure Using X.509 (PKIX)", RFC 5912,
	DOI 10.17487/RFC5912, June 2010, <https://www.rfc-		DOI 10.17487/RFC5912, June 2010, <https://www.rfc-
	editor.org/info/rfc5912>.		editor.org/info/rfc5912>.
	Appendix A. ASN.1 Module		Appendix A. ASN.1 Module
	The following ASN.1 module normatively specifies the SmtpUTF8Name		The following ASN.1 module normatively specifies the SmtpUTF8Mailbox
	structure. This specification uses the ASN.1 definitions from		structure. This specification uses the ASN.1 definitions from
	[RFC5912] with the 2002 ASN.1 notation used in that document.		[RFC5912] with the 2002 ASN.1 notation used in that document.
	[RFC5912] updates normative documents using older ASN.1 notation.		[RFC5912] updates normative documents using older ASN.1 notation.
	LAMPS-EaiAddresses-2016		LAMPS-EaiAddresses-2016
	{ iso(1) identified-organization(3) dod(6)		{ iso(1) identified-organization(3) dod(6)
	internet(1) security(5) mechanisms(5) pkix(7) id-mod(0)		internet(1) security(5) mechanisms(5) pkix(7) id-mod(0)
	id-mod-lamps-eai-addresses-2016(TBD) }		id-mod-lamps-eai-addresses-2016(TBD) }
	DEFINITIONS IMPLICIT TAGS ::=		DEFINITIONS IMPLICIT TAGS ::=
	skipping to change at page 10, line 31 ¶		skipping to change at page 10, line 31 ¶
	{ iso(1) identified-organization(3) dod(6) internet(1) security(5)		{ iso(1) identified-organization(3) dod(6) internet(1) security(5)
	mechanisms(5) pkix(7) id-mod(0) id-mod-pkix1-explicit-02(51) } ;		mechanisms(5) pkix(7) id-mod(0) id-mod-pkix1-explicit-02(51) } ;
	--		--
	-- otherName carries additional name types for subjectAltName,		-- otherName carries additional name types for subjectAltName,
	-- issuerAltName, and other uses of GeneralNames.		-- issuerAltName, and other uses of GeneralNames.
	--		--
	id-on OBJECT IDENTIFIER ::= { id-pkix 8 }		id-on OBJECT IDENTIFIER ::= { id-pkix 8 }
	SmtpUtf8OtherNames OTHER-NAME ::= { on-SmtpUTF8Name, ... }		SmtpUtf8OtherNames OTHER-NAME ::= { on-SmtpUTF8Mailbox, ... }
	on-SmtpUTF8Name OTHER-NAME ::= {		on-SmtpUTF8Mailbox OTHER-NAME ::= {
	SmtpUTF8Name IDENTIFIED BY id-on-SmtpUTF8Name		SmtpUTF8Mailbox IDENTIFIED BY id-on-SmtpUTF8Mailbox
	}		}
	id-on-SmtpUTF8Name OBJECT IDENTIFIER ::= { id-on 9 }		id-on-SmtpUTF8Mailbox OBJECT IDENTIFIER ::= { id-on 9 }
	SmtpUTF8Name ::= UTF8String (SIZE (1..MAX))		SmtpUTF8Mailbox ::= UTF8String (SIZE (1..MAX))
			-- SmtpUTF8Mailbox conforms to Mailbox as specified
			-- in Section 3.3 of RFC 6531.
	END		END
	Appendix B. Example of SmtpUTF8Name		Appendix B. Example of SmtpUTF8Mailbox
	This non-normative example demonstrates using SmtpUTF8Name as an		This non-normative example demonstrates using SmtpUTF8Mailbox as an
	otherName in GeneralName to encode the email address		otherName in GeneralName to encode the email address
	"u+8001u+5E2B@example.com".		"u+8001u+5E2B@example.com".
	The hexadecimal DER encoding of the email address is:		The hexadecimal DER encoding of the email address is:
	A022060A 2B060105 05070012 0809A014 0C12E880 81E5B8AB 40657861		A022060A 2B060105 05070012 0809A014 0C12E880 81E5B8AB 40657861
	6D706C65 2E636F6D		6D706C65 2E636F6D
	The text decoding is:		The text decoding is:
	0 34: [0] {		0 34: [0] {
	2 10: OBJECT IDENTIFIER '1 3 6 1 5 5 7 0 18 8 9'		2 10: OBJECT IDENTIFIER '1 3 6 1 5 5 7 0 18 8 9'
End of changes. 34 change blocks.
	78 lines changed or deleted		84 lines changed or added
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