draft-ietf-precis-framework-01.txt   draft-ietf-precis-framework-02.txt 
Network Working Group M. Blanchet Network Working Group P. Saint-Andre
Internet-Draft Viagenie Internet-Draft Cisco Systems, Inc.
Obsoletes: 3454 (if approved) P. Saint-Andre Obsoletes: 3454 (if approved) M. Blanchet
Intended status: Standards Track Cisco Intended status: Standards Track Viagenie
Expires: May 2, 2012 October 30, 2011 Expires: September 13, 2012 March 12, 2012
PRECIS Framework: Handling Internationalized Strings in Protocols PRECIS Framework: Handling Internationalized Strings in Protocols
draft-ietf-precis-framework-01 draft-ietf-precis-framework-02
Abstract Abstract
Application protocols that make use of Unicode code points in Application protocols using Unicode code points in protocol strings
protocol strings need to prepare such strings in order to perform need to prepare such strings in order to perform comparison
comparison operations (e.g., for purposes of authentication or operations (e.g., for purposes of authentication or authorization).
authorization). In general, this problem has been labeled the This document defines a framework enabling application protocols to
"preparation and comparison of internationalized strings" or use various classes of strings in a way that depends on the
"PRECIS". This document defines a framework that enables application properties of Unicode code points. A specification using this
protocols to prepare various classes of strings in a way that depends framework can either directly use the base string classes or can
on the properties of Unicode code points. Because this framework subclass the base string classes as needed. This framework uses an
does not depend on large tables of Unicode code points as in approach similar to the revised internationalized domain names in
stringprep (RFC 3454), it is more agile with regard to changes in the applications (IDNA) technology (RFC 5890, RFC 5891, RFC 5892, RFC
underlying Unicode database and thus provides improved flexibility to 5893, RFC 5894) and thus adheres to the high-level design goals
application protocols. A specification that uses this framework described in RFC 4690, albeit for application technologies other than
either can directly use the base string classes defined in this the Domain Name System (DNS). This document obsoletes the previous
document or can subclass the base string classes as needed. This framework, named Stringprep, as defined in RFC 3454.
framework uses an approach similar to that of the revised
internationalized domain names in applications (IDNA) technology (RFC
5890, RFC 5891, RFC 5892, RFC 5893, RFC 5894) and thus adheres to the
high-level design goals described in RFC 4690, albeit for application
technologies other than the Domain Name System (DNS). This document
obsoletes RFC 3454.
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 May 2, 2012.
This Internet-Draft will expire on September 13, 2012.
Copyright Notice Copyright Notice
Copyright (c) 2011 IETF Trust and the persons identified as the Copyright (c) 2012 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
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described in the Simplified BSD License. described in the Simplified BSD License.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 5 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 6 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 5
3. String Classes . . . . . . . . . . . . . . . . . . . . . . . . 6 3. String Classes . . . . . . . . . . . . . . . . . . . . . . . . 5
3.1. NameClass . . . . . . . . . . . . . . . . . . . . . . . . 7 3.1. NameClass . . . . . . . . . . . . . . . . . . . . . . . . 6
3.1.1. Valid . . . . . . . . . . . . . . . . . . . . . . . . 7 3.1.1. Valid . . . . . . . . . . . . . . . . . . . . . . . . 6
3.1.2. Disallowed . . . . . . . . . . . . . . . . . . . . . . 8 3.1.2. Disallowed . . . . . . . . . . . . . . . . . . . . . . 7
3.1.3. Unassigned . . . . . . . . . . . . . . . . . . . . . . 8 3.1.3. Unassigned . . . . . . . . . . . . . . . . . . . . . . 7
3.1.4. Directionality . . . . . . . . . . . . . . . . . . . . 8 3.1.4. Directionality . . . . . . . . . . . . . . . . . . . . 7
3.1.5. Case Mapping . . . . . . . . . . . . . . . . . . . . . 8 3.1.5. Case Mapping . . . . . . . . . . . . . . . . . . . . . 7
3.1.6. Normalization . . . . . . . . . . . . . . . . . . . . 8 3.1.6. Normalization . . . . . . . . . . . . . . . . . . . . 7
3.2. FreeClass . . . . . . . . . . . . . . . . . . . . . . . . 8 3.2. FreeClass . . . . . . . . . . . . . . . . . . . . . . . . 8
3.2.1. Valid . . . . . . . . . . . . . . . . . . . . . . . . 9 3.2.1. Valid . . . . . . . . . . . . . . . . . . . . . . . . 8
3.2.2. Disallowed . . . . . . . . . . . . . . . . . . . . . . 9 3.2.2. Disallowed . . . . . . . . . . . . . . . . . . . . . . 8
3.2.3. Unassigned . . . . . . . . . . . . . . . . . . . . . . 9 3.2.3. Unassigned . . . . . . . . . . . . . . . . . . . . . . 8
3.2.4. Directionality . . . . . . . . . . . . . . . . . . . . 9 3.2.4. Directionality . . . . . . . . . . . . . . . . . . . . 8
3.2.5. Case Mapping . . . . . . . . . . . . . . . . . . . . . 9 3.2.5. Case Mapping . . . . . . . . . . . . . . . . . . . . . 9
3.2.6. Normalization . . . . . . . . . . . . . . . . . . . . 10 3.2.6. Normalization . . . . . . . . . . . . . . . . . . . . 9
4. Use of PRECIS String Classes . . . . . . . . . . . . . . . . . 10 4. Use of PRECIS String Classes . . . . . . . . . . . . . . . . . 9
4.1. Principles . . . . . . . . . . . . . . . . . . . . . . . . 10 4.1. Principles . . . . . . . . . . . . . . . . . . . . . . . . 9
4.2. Subclassing . . . . . . . . . . . . . . . . . . . . . . . 10 4.2. Subclassing . . . . . . . . . . . . . . . . . . . . . . . 10
4.3. Registration . . . . . . . . . . . . . . . . . . . . . . . 10 4.3. Registration . . . . . . . . . . . . . . . . . . . . . . . 10
5. Code Point Properties . . . . . . . . . . . . . . . . . . . . 11 5. Code Point Properties . . . . . . . . . . . . . . . . . . . . 10
6. Category Definitions Used to Calculate Derived Property 6. Category Definitions Used to Calculate Derived Property
Value . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Value . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
6.1. LetterDigits (A) . . . . . . . . . . . . . . . . . . . . . 13 6.1. LetterDigits (A) . . . . . . . . . . . . . . . . . . . . . 13
6.2. Unstable (B) . . . . . . . . . . . . . . . . . . . . . . . 13 6.2. Unstable (B) . . . . . . . . . . . . . . . . . . . . . . . 13
6.3. IgnorableProperties (C) . . . . . . . . . . . . . . . . . 14 6.3. IgnorableProperties (C) . . . . . . . . . . . . . . . . . 13
6.4. IgnorableBlocks (D) . . . . . . . . . . . . . . . . . . . 14 6.4. IgnorableBlocks (D) . . . . . . . . . . . . . . . . . . . 13
6.5. LDH (E) . . . . . . . . . . . . . . . . . . . . . . . . . 14 6.5. LDH (E) . . . . . . . . . . . . . . . . . . . . . . . . . 13
6.6. Exceptions (F) . . . . . . . . . . . . . . . . . . . . . . 14 6.6. Exceptions (F) . . . . . . . . . . . . . . . . . . . . . . 13
6.7. BackwardCompatible (G) . . . . . . . . . . . . . . . . . . 15 6.7. BackwardCompatible (G) . . . . . . . . . . . . . . . . . . 15
6.8. JoinControl (H) . . . . . . . . . . . . . . . . . . . . . 16 6.8. JoinControl (H) . . . . . . . . . . . . . . . . . . . . . 15
6.9. OldHangulJamo (I) . . . . . . . . . . . . . . . . . . . . 16 6.9. OldHangulJamo (I) . . . . . . . . . . . . . . . . . . . . 16
6.10. Unassigned (J) . . . . . . . . . . . . . . . . . . . . . . 16 6.10. Unassigned (J) . . . . . . . . . . . . . . . . . . . . . . 16
6.11. ASCII7 (K) . . . . . . . . . . . . . . . . . . . . . . . . 17 6.11. ASCII7 (K) . . . . . . . . . . . . . . . . . . . . . . . . 16
6.12. Controls (L) . . . . . . . . . . . . . . . . . . . . . . . 17 6.12. Controls (L) . . . . . . . . . . . . . . . . . . . . . . . 16
6.13. PrecisIgnorableProperties (M) . . . . . . . . . . . . . . 17 6.13. PrecisIgnorableProperties (M) . . . . . . . . . . . . . . 17
6.14. Spaces (N) . . . . . . . . . . . . . . . . . . . . . . . . 17 6.14. Spaces (N) . . . . . . . . . . . . . . . . . . . . . . . . 17
6.15. Symbols (O) . . . . . . . . . . . . . . . . . . . . . . . 17 6.15. Symbols (O) . . . . . . . . . . . . . . . . . . . . . . . 17
6.16. Punctuation (P) . . . . . . . . . . . . . . . . . . . . . 18 6.16. Punctuation (P) . . . . . . . . . . . . . . . . . . . . . 17
6.17. HasCompat (Q) . . . . . . . . . . . . . . . . . . . . . . 18 6.17. HasCompat (Q) . . . . . . . . . . . . . . . . . . . . . . 17
7. Calculation of the Derived Property . . . . . . . . . . . . . 18 7. Calculation of the Derived Property . . . . . . . . . . . . . 18
8. Code Points . . . . . . . . . . . . . . . . . . . . . . . . . 19 8. Code Points . . . . . . . . . . . . . . . . . . . . . . . . . 19
9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 19 9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 19
9.1. PRECIS Derived Property Value Registry . . . . . . . . . . 19 9.1. PRECIS Derived Property Value Registry . . . . . . . . . . 19
9.2. PRECIS Usage Registry . . . . . . . . . . . . . . . . . . 20 9.2. PRECIS Usage Registry . . . . . . . . . . . . . . . . . . 19
10. Security Considerations . . . . . . . . . . . . . . . . . . . 20 10. Security Considerations . . . . . . . . . . . . . . . . . . . 20
10.1. General Issues . . . . . . . . . . . . . . . . . . . . . . 20 10.1. General Issues . . . . . . . . . . . . . . . . . . . . . . 20
10.2. Local Character Set Issues . . . . . . . . . . . . . . . . 21 10.2. Local Character Set Issues . . . . . . . . . . . . . . . . 20
10.3. Visually Similar Characters . . . . . . . . . . . . . . . 21 10.3. Visually Similar Characters . . . . . . . . . . . . . . . 20
10.4. Security of Passwords and Passphrases . . . . . . . . . . 23 10.4. Security of Passwords and Passphrases . . . . . . . . . . 22
11. Interoperability Considerations . . . . . . . . . . . . . . . 23 11. Interoperability Considerations . . . . . . . . . . . . . . . 23
12. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 24 12. References . . . . . . . . . . . . . . . . . . . . . . . . . . 23
13. Codepoints 0x0000 - 0x10FFFF . . . . . . . . . . . . . . . . . 24 12.1. Normative References . . . . . . . . . . . . . . . . . . . 23
13.1. Codepoints in Unicode Character Database (UCD) format . . 24 12.2. Informative References . . . . . . . . . . . . . . . . . . 24
14. References . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Appendix A. Codepoints 0x0000 - 0x10FFFF . . . . . . . . . . . . 26
14.1. Normative References . . . . . . . . . . . . . . . . . . . 24 A.1. Codepoints in Unicode Character Database (UCD) format . . 26
14.2. Informative References . . . . . . . . . . . . . . . . . . 24 Appendix B. Acknowledgements . . . . . . . . . . . . . . . . . . 30
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 26 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 30
1. Introduction 1. Introduction
A number of IETF application technologies use stringprep [RFC3454] as As described in [I-D.ietf-precis-problem-statement], many IETF
the basis for comparing protocol strings that contain Unicode protocols use the Stringprep [RFC3454] framework as the basis for
characters or "code points" [UNICODE]. Since the publication of preparing and comparing protocol strings that contain Unicode code
[RFC3454] in 2002, the Internet community has gained much more points [UNICODE]. The Stringprep framework was defined during work
experience with internationalization, some of it reflected in on the original technology for internationalized domain names (IDNs),
[RFC4690]. In particular, the IETF's technology for IDNA2003 [RFC3490], as a way to enable other protocols to use the
internationalized domain names (IDNs) has changed significantly: same or similar method by defining a Stringprep profile to prepare
IDNA2003 [RFC3490], which was based on stringprep, has been and compare strings and identifiers in these protocols. Nameprep
superseded by IDNA2008 ([RFC5890], [RFC5891], [RFC5892], [RFC5893], [RFC3491] was such a profile for the IDN case. Since then, issues
[RFC5894]), which does not use stringprep. This migration away from were documented [RFC4690] related to the IDN and Nameprep cases. The
stringprep for internationalized domain names has prompted other new IDN specifications, named IDNA2008 ([RFC5890], [RFC5891],
"customers" of stringprep to consider new approaches to the [RFC5892], [RFC5893], [RFC5894]), do not use Stringprep and Nameprep
preparation and comparison of internationalized strings ("PRECIS"), anymore. This migration away from Stringprep for internationalized
as described in [PROBLEM]. domain names has prompted other "customers" of Stringprep to consider
new approaches to the preparation and comparison of internationalized
strings ("PRECIS"), as described in
[I-D.ietf-precis-problem-statement].
This document proposes a technical framework for a post-stringprep This document defines a technical framework for a post-stringprep
approach to the preparation and comparison of internationalized approach to the preparation and comparison of internationalized
strings in application protocols. The framework is based on several strings in application protocols. The framework is based on several
principles: principles:
1. Define a small set of base string classes appropriate for common 1. Define a small set of base string classes appropriate for common
application protocol constructs such as usernames and free-form application protocol constructs such as usernames and free-form
strings. strings.
2. Define each base string class in terms of Unicode code points and 2. Define each base string class in terms of Unicode code points and
their properties, specifying whether each code point or character their properties, specifying whether each code point or character
skipping to change at page 6, line 18 skipping to change at page 5, line 23
copy/paste operations between software implementing different copy/paste operations between software implementing different
application protocols will be more predictable and coherent. application protocols will be more predictable and coherent.
Although this framework is similar to IDNA2008 and borrows some of Although this framework is similar to IDNA2008 and borrows some of
the character categories defined in [RFC5892], it defines additional the character categories defined in [RFC5892], it defines additional
string classes and character categories to meet the needs of common string classes and character categories to meet the needs of common
application protocols. application protocols.
2. Terminology 2. Terminology
Many important terms used in this document are defined in [PROBLEM], Many important terms used in this document are defined in
[RFC6365], [RFC5890], and [UNICODE]. [I-D.ietf-precis-problem-statement], [RFC6365], [RFC5890], and
[UNICODE].
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in "OPTIONAL" in this document are to be interpreted as described in
[RFC2119]. [RFC2119].
3. String Classes 3. String Classes
IDNA2008 essentially defines a base string class of internationalized IDNA2008 essentially defines a base string class of internationalized
domain name, although it does not use the term "string class". (This domain name, although it does not use the term "string class". (This
document does not define a string class for domain names, and document does not define a string class for domain names, and
application protocols are strongly encouraged to use IDNA2008 as the application protocols are strongly encouraged to use IDNA2008 as the
appropriate method to prepare domain names and hostnames.) appropriate method to prepare domain names and hostnames.)
We propose the following additional base string classes for use in We propose the following additional base string classes for use in
application protocols: application protocols:
NameClass: a sequence of letters, numbers, and symbols that is used NameClass: a sequence of letters, numbers, and symbols that is used
to identify or address a network entity such as a user, an to identify or address a network entity such as a user account, a
account, a venue (e.g., a chatroom), an information source (e.g., venue (e.g., a chatroom), an information source (e.g., a data
a data feed), or a collection of data (e.g., a file). feed), or a collection of data (e.g., a file).
FreeClass: a sequence of letters, numbers, symbols, spaces, and FreeClass: a sequence of letters, numbers, symbols, spaces, and
other code points that is used for free-form strings, including other code points that is used for free-form strings, including
passwords and passphrases as well as display elements such as a passwords and passphrases as well as display elements such as a
human-friendly nickname in a chatroom. human-friendly nickname in a chatroom.
Note: [PROBLEM] mentions a class of "string blobs" containing
"elements of the protocol that look like strings to users, but that
are passed around in the protocol unchanged and that cannot be used
for comparison or other purposes." It is an open question whether
application protocols need to apply preparation and comparison rules
to such strings.
The following subsections discuss these string classes in more The following subsections discuss these string classes in more
detail, with reference to the dimensions described in Section 3 of detail, with reference to the dimensions described in Section 3 of
[PROBLEM]. [I-D.ietf-precis-problem-statement].
Each string class is defined by the following behavioral rules: Each string class is defined by the following behavioral rules:
Valid: defines which code points and character categories are Valid: defines which code points and character categories are
treated as valid input to preparation of the string. treated as valid input to preparation of the string.
Disallowed: defines which code points and character categories are Disallowed: defines which code points and character categories are
treated as disallowed during preparation of the string. treated as disallowed during preparation of the string.
Unassigned: defines application behavior in the presence of code Unassigned: defines application behavior in the presence of code
points that are unassigned, i.e. unknown for the version of points that are unassigned, i.e. unknown for the version of
Unicode the application is built upon. Unicode the application is built upon.
Directionality: defines application behavior in the presence of code Directionality: defines application behavior in the presence of code
points that have directionality, in particular right-to-left code points that have directionality, in particular right-to-left code
points as defined in the Unicode database (see [UAX9]). points as defined in the Unicode database (see [UAX9]).
Casemapping: defines if case mapping is used for this class, and how Casemapping: defines if case mapping is used for this class (instead
the mapping is done. of case preservation), and how the mapping is done.
Normalization: defines which Unicode normalization form (D, KD, C, Normalization: defines which Unicode normalization form (D, KD, C,
or KC) is to be applied (see [UAX15]). or KC) is to be applied (see [UAX15]).
This document defines the valid, disallowed, and unassigned rules. This document defines the valid, disallowed, and unassigned rules.
Application protocols that use the PRECIS string classes MUST define Application protocols that use the PRECIS string classes MUST define
the directionality, casemapping, and normalization rules, as further the directionality, casemapping, and normalization rules, as further
described under Section 9.2. described under Section 9.2.
3.1. NameClass 3.1. NameClass
skipping to change at page 7, line 47 skipping to change at page 7, line 4
3.1. NameClass 3.1. NameClass
Most application technologies need a special class of strings that Most application technologies need a special class of strings that
can be used to refer to, include, or communicate things like can be used to refer to, include, or communicate things like
usernames, file names, data feed names, and chatroom names. We group usernames, file names, data feed names, and chatroom names. We group
such things into a bucket called "NameClass" having the following such things into a bucket called "NameClass" having the following
features. features.
3.1.1. Valid 3.1.1. Valid
o Letters and numbers, i.e., the LetterDigits ("A") category first o Letters and numbers, i.e., the LetterDigits ("A") category first
defined in [RFC5892] and listed here under Section 6.1. defined in [RFC5892] and listed here under Section 6.1.
o Code points in the range U+0021 through U+007E, i.e., the ASCII7 o Code points in the range U+0021 through U+007E, i.e., the ASCII7
("K") rule defined under Section 6.11. These code points are ("K") rule defined under Section 6.11. These code points are
valid even if they would otherwise be disallowed according to the valid even if they would otherwise be disallowed according to the
property-based rules specified in the next section. property-based rules specified in the next section.
3.1.2. Disallowed 3.1.2. Disallowed
o Control characters, i.e., the Controls ("L") category defined o Control characters, i.e., the Controls ("L") category defined
under Section 6.12. under Section 6.12.
o Ignorable characters, i.e., the PrecisIgnorableProperties ("M")
category defined under Section 6.13.
o Space characters, i.e., the Spaces ("N") category defined under o Space characters, i.e., the Spaces ("N") category defined under
Section 6.14. Section 6.14.
o Symbol characters, i.e., the Symbols ("O") category defined under o Symbol characters, i.e., the Symbols ("O") category defined under
Section 6.15. Section 6.15.
o Punctuation characters, i.e., the Punctuation ("P") category o Punctuation characters, i.e., the Punctuation ("P") category
defined under Section 6.16. defined under Section 6.16.
o Any character that has a compatibility equivalent, i.e., the o Any character that has a compatibility equivalent, i.e., the
HasCompat ("Q") category defined under Section 6.17. These code HasCompat ("Q") category defined under Section 6.17. These code
points are disallowed even if they would otherwise be valid points are disallowed even if they would otherwise be valid
according to the property-based rules specified in the previous according to the property-based rules specified in the previous
skipping to change at page 8, line 52 skipping to change at page 8, line 8
The normalization form MUST be specified by each application protocol The normalization form MUST be specified by each application protocol
that uses or subclasses the NameClass. that uses or subclasses the NameClass.
However, in accordance with [RFC5198], normalization form C (NFC) is However, in accordance with [RFC5198], normalization form C (NFC) is
RECOMMENDED. RECOMMENDED.
3.2. FreeClass 3.2. FreeClass
Some application technologies need a special class of strings that Some application technologies need a special class of strings that
can be used in a free-form way (e.g., as a passphrase or a nickname can be used in a free-form way, e.g., as a passphrase in an
in a chatroom). We group such things into a bucket called authentication exchange (see [I-D.melnikov-precis-saslprepbis] or a
"FreeClass" having the following features. nickname in a chatroom (see [I-D.saintandre-precis-nickname]). We
group such things into a bucket called "FreeClass" having the
following features.
NOTE: Consult Section 10.4 for relevant security considerations when NOTE: Consult Section 10.4 for relevant security considerations when
strings conforming to the FreeClass, or a subclass thereof, are used strings conforming to the FreeClass, or a subclass thereof, are used
as passwords or passphrases. as passwords or passphrases.
3.2.1. Valid 3.2.1. Valid
o Letters and numbers, i.e., the LetterDigits ("A") category first o Letters and numbers, i.e., the LetterDigits ("A") category first
defined in [RFC5892] and listed here under Section 6.1. defined in [RFC5892] and listed here under Section 6.1.
o Code points in the range U+0021 through U+007E, i.e., the ASCII7 o Code points in the range U+0021 through U+007E, i.e., the ASCII7
skipping to change at page 9, line 30 skipping to change at page 8, line 37
Section 6.14. Section 6.14.
o Symbol characters, i.e., the Symbols ("O") category defined under o Symbol characters, i.e., the Symbols ("O") category defined under
Section 6.15. Section 6.15.
o Punctuation characters, i.e., the Punctuation ("P") category o Punctuation characters, i.e., the Punctuation ("P") category
defined under Section 6.16. defined under Section 6.16.
3.2.2. Disallowed 3.2.2. Disallowed
o Control characters, i.e., the Controls ("L") category defined o Control characters, i.e., the Controls ("L") category defined
under Section 6.12. under Section 6.12.
o Ignorable characters, i.e., the PrecisIgnorableProperties ("M")
category defined under Section 6.13.
3.2.3. Unassigned 3.2.3. Unassigned
Any code points that are not yet assigned in the Unicode character Any code points that are not yet assigned in the Unicode character
set SHALL be considered Unassigned for purposes of the FreeClass. set SHALL be considered Unassigned for purposes of the FreeClass.
3.2.4. Directionality 3.2.4. Directionality
The directionality rule MUST be specified by each application The directionality rule MUST be specified by each application
protocol that uses or subclasses the FreeClass. protocol that uses or subclasses the FreeClass.
3.2.5. Case Mapping 3.2.5. Case Mapping
The casemapping rule MUST be specified by each application protocol The casemapping rule MUST be specified by each application protocol
that uses or subclasses the FreeClass. that uses or subclasses the FreeClass.
In general, case preservation is NOT RECOMMENDED for application
protocols that perform case-insensitive comparison of
internationalized strings; instead, application protocols SHOULD
either (a) not preserve case but perform case-insensitive matching or
(b) preserve case but perform case-sensitive comparison.
In order to maximize entropy, it is NOT RECOMMENDED for application In order to maximize entropy, it is NOT RECOMMENDED for application
protocols to map uppercase and titlecase code points to their protocols to map uppercase and titlecase code points to their
lowercase equivalents when strings conforming to the FreeClass, or a lowercase equivalents when strings conforming to the FreeClass, or a
subclass thereof, are used in passwords or passphrases; instead, it subclass thereof, are used in passwords or passphrases; instead, it
is RECOMMENDED to preserve the case of all code points contained in is RECOMMENDED to preserve the case of all code points contained in
such strings. such strings.
3.2.6. Normalization 3.2.6. Normalization
The normalization form MUST be specified by each application protocol The normalization form MUST be specified by each application protocol
skipping to change at page 11, line 34 skipping to change at page 11, line 14
PROTOCOL VALID Those code points that are allowed to be used in any PROTOCOL VALID Those code points that are allowed to be used in any
PRECIS string class (NameClass and FreeClass). Code points with PRECIS string class (NameClass and FreeClass). Code points with
this property value are permitted for general use in any string this property value are permitted for general use in any string
class. The abbreviated term PVALID is used to refer to this value class. The abbreviated term PVALID is used to refer to this value
in the remainder of this document. in the remainder of this document.
SPECIFIC CLASS PROTOCOL VALID Those code points that are allowed to SPECIFIC CLASS PROTOCOL VALID Those code points that are allowed to
be used in specific string classes. Code points with this be used in specific string classes. Code points with this
property value are permitted for use in specific string classes. property value are permitted for use in specific string classes.
In the remainder of this document, the abbreviated term *_PVALID In the remainder of this document, the abbreviated term *_PVAL is
is used, where * = (NAMECLASS | SECRETCLASS | FREECLASS). used, where * = (NAME | FREE), i.e., either FREE_PVAL or
NAME_PVAL.
CONTEXTUAL RULE REQUIRED Some characteristics of the character, such CONTEXTUAL RULE REQUIRED Some characteristics of the character, such
as its being invisible in certain contexts or problematic in as its being invisible in certain contexts or problematic in
others, require that it not be used in labels unless specific others, require that it not be used in labels unless specific
other characters or properties are present. The abbreviated term other characters or properties are present. The abbreviated term
CONTEXT is used to refer to this value in the remainder of this CONTEXT is used to refer to this value in the remainder of this
document. There are two subdivisions of CONTEXTUAL RULE REQUIRED, document. There are two subdivisions of CONTEXTUAL RULE REQUIRED,
the first for Join_controls (called CONTEXTJ) and the second for the first for Join_controls (called CONTEXTJ) and the second for
other characters (called CONTEXTO). other characters (called CONTEXTO).
DISALLOWED Those code points that must not be included in any string DISALLOWED Those code points that must not be included in any string
class. Code points with this property value are not permitted in class. Code points with this property value are not permitted in
any string class. any string class.
SPECIFIC CLASS DISALLOWED Those code points that are not to be SPECIFIC CLASS DISALLOWED Those code points that are not to be
included in a specific string class. Code points with this included in a specific string class. Code points with this
property value are not permitted in one of the string classes but property value are not permitted in one of the string classes but
might be permitted in others. In the remainder of this document, might be permitted in others. In the remainder of this document,
the abbreviated term *_DISALLOWED is used, where * = (NAMECLASS | the abbreviated term *_DIS is used, where * = (NAME | FREE), i.e.,
SECRETCLASS | FREECLASS). either FREE_DIS or NAME_DIS.
UNASSIGNED Those code points that are not designated (i.e. are UNASSIGNED Those code points that are not designated (i.e. are
unassigned) in the Unicode Standard. unassigned) in the Unicode Standard.
The mechanisms described here allow determination of the value of the The mechanisms described here allow determination of the value of the
property for future versions of Unicode (including characters added property for future versions of Unicode (including characters added
after Unicode 5.2 or 6.0 depending on the category, since some after Unicode 5.2 or 6.1 depending on the category, since some
categories in this document are reused from IDNA2008). Changes in categories in this document are reused from IDNA2008 and therefore
Unicode properties that do not affect the outcome of this process do were defined at the time of Unicode 5.2). Changes in Unicode
not affect this framework. For example, a character can have its properties that do not affect the outcome of this process do not
Unicode General_Category value [UNICODE] change from So to Sm, or affect this framework. For example, a character can have its Unicode
from Lo to Ll, without affecting the algorithm results. Moreover, General_Category value [UNICODE] change from So to Sm, or from Lo to
even if such changes were to result, the BackwardCompatible list Ll, without affecting the algorithm results. Moreover, even if such
(Section 6.7) can be adjusted to ensure the stability of the results. changes were to result, the BackwardCompatible list (Section 6.7) can
be adjusted to ensure the stability of the results.
Some code points need to be allowed in exceptional circumstances, but Some code points need to be allowed in exceptional circumstances, but
should be excluded in all other cases; these rules are also described should be excluded in all other cases; these rules are also described
in other documents. The most notable of these are the Join Control in other documents. The most notable of these are the Join Control
characters, U+200D ZERO WIDTH JOINER and U+200C ZERO WIDTH NON- characters, U+200D ZERO WIDTH JOINER and U+200C ZERO WIDTH NON-
JOINER. Both of them have the derived property value CONTEXTJ. A JOINER. Both of them have the derived property value CONTEXTJ. A
character with the derived property value CONTEXTJ or CONTEXTO character with the derived property value CONTEXTJ or CONTEXTO
(CONTEXTUAL RULE REQUIRED) is not to be used unless an appropriate (CONTEXTUAL RULE REQUIRED) is not to be used unless an appropriate
rule has been established and the context of the character is rule has been established and the context of the character is
consistent with that rule. It is invalid to generate a string consistent with that rule. It is invalid to generate a string
skipping to change at page 17, line 28 skipping to change at page 17, line 14
6.13. PrecisIgnorableProperties (M) 6.13. PrecisIgnorableProperties (M)
This PRECIS-specific category is used to group code points that are This PRECIS-specific category is used to group code points that are
not recommended for use in PRECIS string classes. not recommended for use in PRECIS string classes.
M: Default_Ignorable_Code_Point(cp) = True or M: Default_Ignorable_Code_Point(cp) = True or
Noncharacter_Code_Point(cp) = True Noncharacter_Code_Point(cp) = True
The definition for Default_Ignorable_Code_Point can be found in the The definition for Default_Ignorable_Code_Point can be found in the
DerivedCoreProperties.txt [2] file, and at the time of Unicode 6.0 is DerivedCoreProperties.txt [2] file, and at the time of Unicode 6.1 is
as follows: as follows:
Other_Default_Ignorable_Code_Point Other_Default_Ignorable_Code_Point
+ Cf (Format characters) + Cf (Format characters)
+ Variation_Selector + Variation_Selector
- White_Space - White_Space
- FFF9..FFFB (Annotation Characters) - FFF9..FFFB (Annotation Characters)
- 0600..0603, 06DD, 070F (exceptional Cf characters - 0600..0604, 06DD, 070F, 110BD (exceptional Cf characters
that should be visible) that should be visible)
6.14. Spaces (N) 6.14. Spaces (N)
This PRECIS-specific category is used to group code points that are This PRECIS-specific category is used to group code points that are
space characters. space characters.
N: General_Category(cp) is in {Zs} N: General_Category(cp) is in {Zs}
6.15. Symbols (O) 6.15. Symbols (O)
This PRECIS-specific category is used to group code points that are This PRECIS-specific category is used to group code points that are
symbols. symbols.
O: General_Category(cp) is in {Sc} O: General_Category(cp) is in {Sm, Sc, Sk, So}
6.16. Punctuation (P) 6.16. Punctuation (P)
This PRECIS-specific category is used to group code points that are This PRECIS-specific category is used to group code points that are
punctuation marks. punctuation characters.
P: General_Category(cp) is in {Pi} P: General_Category(cp) is in {Pc, Pd, Ps, Pe, Pi, Pf, Po}
6.17. HasCompat (Q) 6.17. HasCompat (Q)
This PRECIS-specific category is used to group code points that have This PRECIS-specific category is used to group code points that have
compatibility equivalents as explained in Chapter 2 and Chapter 3 of compatibility equivalents as explained in Chapter 2 and Chapter 3 of
[UNICODE]. [UNICODE].
Q: toNFKC(cp) != cp Q: toNFKC(cp) != cp
The toNFKC() operation returns the code point in normalization form The toNFKC() operation returns the code point in normalization form
KC. For more information, see Section 5 of [UAX15]. KC. For more information, see Section 5 of [UAX15].
7. Calculation of the Derived Property 7. Calculation of the Derived Property
Possible values of the derived property are: Possible values of the derived property are:
o PVALID o PVALID
o NAMECLASS_VALID o NAME_PVAL
o SECRETCLASS_VALID o FREE_PVAL
o FREECLASS_VALID
o CONTEXTJ o CONTEXTJ
o CONTEXTO o CONTEXTO
o DISALLOWED o DISALLOWED
o NAMECLASS_DISALLOWED o NAME_DIS
o SECRETCLASS_DISALLOWED o FREE_DIS
o FREECLASS_DISALLOWED
o UNASSIGNED o UNASSIGNED
NOTE: In some instances, the value of the derived property calculated NOTE: In some instances, the value of the derived property calculated
depends on the string class (e.g., if an identifier used in an depends on the string class (e.g., if an identifier used in an
application protocol is defined as using or subclassing the PRECIS application protocol is defined as using or subclassing the PRECIS
NameClass, then a space character would be assigned to NameClass, then a space character would be assigned to NAME_DIS).
NAMECLASS_DISALLOWED).
The algorithm to calculate the value of the derived property is as The algorithm to calculate the value of the derived property is as
follows. (NOTE: Use of the name of a rule (such as "Exception") follows. (NOTE: Use of the name of a rule (such as "Exception")
implies the set of code points that the rule defines, whereas the implies the set of code points that the rule defines, whereas the
same name as a function call (such as "Exception(cp)") implies the same name as a function call (such as "Exception(cp)") implies the
value that the code point has in the Exceptions table.) value that the code point has in the Exceptions table.)
If .cp. .in. Exceptions Then Exceptions(cp); If .cp. .in. Exceptions Then Exceptions(cp);
Else If .cp. .in. BackwardCompatible Then BackwardCompatible(cp); Else If .cp. .in. BackwardCompatible Then BackwardCompatible(cp);
Else If .cp. .in. Unassigned Then UNASSIGNED; Else If .cp. .in. Unassigned Then UNASSIGNED;
Else If .cp. .in. ASCII7 Then PVALID; Else If .cp. .in. ASCII7 Then PVALID;
Else If .cp. .in. JoinControl Then CONTEXTJ; Else If .cp. .in. JoinControl Then CONTEXTJ;
Else If .cp. .in. PrecisIgnorableProperties Then DISALLOWED; Else If .cp. .in. PrecisIgnorableProperties Then DISALLOWED;
Else If .cp. .in. Controls Then DISALLOWED; Else If .cp. .in. Controls Then DISALLOWED;
Else If .cp. .in. OldHangulJamo Then DISALLOWED; Else If .cp. .in. OldHangulJamo Then DISALLOWED;
Else If .cp. .in. LetterDigits Then PVALID; Else If .cp. .in. LetterDigits Then PVALID;
Else If .cp. .in. Spaces Then NAMECLASS_DISALLOWED Else If .cp. .in. Spaces Then NAME_DIS
or SECRETCLASS_DISALLOWED or FREE_PVAL;
or FREECLASS_VALID; Else If .cp. .in. Symbols Then NAME_DIS
Else If .cp. .in. Symbols Then NAMECLASS_DISALLOWED or FREE_PVAL;
or SECRETCLASS_DISALLOWED Else If .cp. .in. Punctuation Then NAME_DIS
or FREECLASS_VALID; or FREE_PVAL;
Else If .cp. .in. Punctuation Then NAMECLASS_DISALLOWED Else If .cp. .in. HasCompat Then NAME_DIS
or SECRETCLASS_DISALLOWED or FREE_PVAL;
or FREECLASS_VALID;
Else If .cp. .in. HasCompat Then NAMECLASS_DISALLOWED
or SECRETCLASS_VALID
or FREECLASS_VALID;
Else DISALLOWED; Else DISALLOWED;
8. Code Points 8. Code Points
The Categories and Rules defined in Section 6 and Section 7 apply to The Categories and Rules defined in Section 6 and Section 7 apply to
all Unicode code points. The table in Section 13 shows, for all Unicode code points. The table in Appendix A shows, for
illustrative purposes, the consequences of the categories and illustrative purposes, the consequences of the categories and
classification rules, and the resulting property values. classification rules, and the resulting property values.
The list of code points that can be found in Section 13 is non- The list of code points that can be found in Appendix A is non-
normative. Instead, the rules defined by Section 6 and Section 7 are normative. Instead, the rules defined by Section 6 and Section 7 are
normative, and any tables are derived from the rules. normative, and any tables are derived from the rules.
9. IANA Considerations 9. IANA Considerations
9.1. PRECIS Derived Property Value Registry 9.1. PRECIS Derived Property Value Registry
IANA is requested to create a PRECIS-specific registry with the IANA is requested to create a PRECIS-specific registry with the
Derived Properties for the versions of Unicode that are released Derived Properties for the versions of Unicode that are released
after (and including) version 6.0. The derived property value is to after (and including) version 6.1. The derived property value is to
be calculated in cooperation with a designated expert [RFC5226] be calculated in cooperation with a designated expert [RFC5226]
according to the specifications in Section 6 and Section 7, and not according to the specifications in Section 6 and Section 7, and not
by copying the non-normative table found in Section 13. by copying the non-normative table found in Appendix A.
If during this process (creation of the table of derived property If during this process (creation of the table of derived property
values) followed by a designated expert review, either backward- values) followed by a designated expert review, either backward-
incompatible changes to the table of derived properties are incompatible changes to the table of derived properties are
discovered, or otherwise problems during the creation of the table discovered, or otherwise problems arise during the creation of the
arises, that is to be flagged to the IESG. Changes to the rules (as table, that is to be flagged to the IESG. Changes to the rules (as
specified in Section 6 and Section 7) require IETF Review, as specified in Section 6 and Section 7) require IETF Review, as
described in [RFC5226]. described in [RFC5226].
9.2. PRECIS Usage Registry 9.2. PRECIS Usage Registry
IANA is requested to create a registry of application protocols that IANA is requested to create a registry of application protocols that
use the base string classes. The registry will include one entry for use the base string classes. The registry will include one entry for
each use (e.g., if a protocol uses both the NameClass and the each use (e.g., if a protocol uses both the NameClass and the
FreeClass then the specification for that protocol would submit two FreeClass then the specification for that protocol would submit two
registrations). In accordance with [RFC5226], the registration registrations). In accordance with [RFC5226], the registration
skipping to change at page 20, line 50 skipping to change at page 20, line 31
strings. For example, such strings can be used to make strings. For example, such strings can be used to make
authentication and authorization decisions, and the security of an authentication and authorization decisions, and the security of an
application could be compromised if an entity providing a given application could be compromised if an entity providing a given
string is connected to the wrong account or online resource based on string is connected to the wrong account or online resource based on
different interpretations of the string. different interpretations of the string.
Specifications of application protocols that use this framework are Specifications of application protocols that use this framework are
encouraged to describe how internationalized strings are used in the encouraged to describe how internationalized strings are used in the
protocol, including the security implications of any false positives protocol, including the security implications of any false positives
and false negatives that might result from various comparison and false negatives that might result from various comparison
operations. For some helpful guidelines, refer to [IDENTIFIER], operations. For some helpful guidelines, refer to
[I-D.iab-identifier-comparison], [RFC5890], [UTR36], and [UTR39].
[RFC5890], [UTR36], and [UTR39].
10.2. Local Character Set Issues 10.2. Local Character Set Issues
When systems use local character sets other than ASCII and Unicode, When systems use local character sets other than ASCII and Unicode,
these specifications leave the problem of converting between the these specifications leave the problem of converting between the
local character set and Unicode up to the application or local local character set and Unicode up to the application or local
system. If different applications (or different versions of one system. If different applications (or different versions of one
application) implement different rules for conversions among coded application) implement different rules for conversions among coded
character sets, they could interpret the same name differently and character sets, they could interpret the same name differently and
contact different application servers or other network entities. contact different application servers or other network entities.
skipping to change at page 24, line 7 skipping to change at page 23, line 34
It is known that some existing systems are unable to support the full It is known that some existing systems are unable to support the full
Unicode character set, or even any characters outside the US-ASCII Unicode character set, or even any characters outside the US-ASCII
range. If two (or more) applications need to interoperate when range. If two (or more) applications need to interoperate when
exchanging data (e.g., for the purpose of authenticating a username exchanging data (e.g., for the purpose of authenticating a username
or password), they will naturally need have in common at least one or password), they will naturally need have in common at least one
coded character set (as defined by [RFC6365]). Establishing such a coded character set (as defined by [RFC6365]). Establishing such a
baseline is a matter for the using protocol, not the PRECIS baseline is a matter for the using protocol, not the PRECIS
framework. framework.
12. Acknowledgements 12. References
The authors would like to acknowledge the comments and contributions
of the following individuals: David Black, Mark Davis, Alan DeKok,
Martin Duerst, Patrik Faltstrom, Ted Hardie, Joe Hildebrand, Paul
Hoffman, Jeffrey Hutzelman, Simon Josefsson, John Klensin, Alexey
Melnikov, Yoav Nir, Mike Parker, Pete Resnick, Andrew Sullivan, Dave
Thaler, and Yoshiro Yoneya.
Some algorithms and textual descriptions have been borrowed from
[RFC5892]. Some text regarding security has been borrowed from
[RFC5890] and [XMPP-ADDR].
13. Codepoints 0x0000 - 0x10FFFF
To follow.
13.1. Codepoints in Unicode Character Database (UCD) format
To follow.
14. References
14.1. Normative References 12.1. Normative References
[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.
[RFC5198] Klensin, J. and M. Padlipsky, "Unicode Format for Network [RFC5198] Klensin, J. and M. Padlipsky, "Unicode Format for Network
Interchange", RFC 5198, March 2008. Interchange", RFC 5198, March 2008.
[UNICODE] The Unicode Consortium, "The Unicode Standard, Version [UNICODE] The Unicode Consortium, "The Unicode Standard, Version
6.0", 2010, 6.0", 2010,
<http://www.unicode.org/versions/Unicode6.0.0/>. <http://www.unicode.org/versions/Unicode6.0.0/>.
14.2. Informative References 12.2. Informative References
[IDENTIFIER] [I-D.iab-identifier-comparison]
Thaler, D., "Issues in Identifier Comparison for Security Thaler, D., "Issues in Identifier Comparison for Security
Purposes", draft-iab-identifier-comparison-00 (work in Purposes", draft-iab-identifier-comparison-00 (work in
progress), July 2011. progress), July 2011.
[PROBLEM] Blanchet, M. and A. Sullivan, "Stringprep Revision Problem [I-D.ietf-precis-problem-statement]
Statement", draft-ietf-precis-problem-statement-03 (work Sullivan, A. and M. Blanchet, "Stringprep Revision Problem
in progress), July 2011. Statement", draft-ietf-precis-problem-statement-04 (work
in progress), January 2012.
[I-D.ietf-xmpp-6122bis]
Saint-Andre, P., "Extensible Messaging and Presence
Protocol (XMPP): Address Format",
draft-ietf-xmpp-6122bis-00 (work in progress),
November 2011.
[I-D.melnikov-precis-saslprepbis]
Melnikov, A. and P. Saint-Andre, "Username and Password
Preparation Algorithms",
draft-melnikov-precis-saslprepbis-00 (work in progress),
March 2012.
[I-D.saintandre-precis-nickname]
Saint-Andre, P., "Preparation and Comparison of
Nicknames", draft-saintandre-precis-nickname-00 (work in
progress), March 2012.
[RFC2865] Rigney, C., Willens, S., Rubens, A., and W. Simpson, [RFC2865] Rigney, C., Willens, S., Rubens, A., and W. Simpson,
"Remote Authentication Dial In User Service (RADIUS)", "Remote Authentication Dial In User Service (RADIUS)",
RFC 2865, June 2000. RFC 2865, June 2000.
[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.
[RFC3490] Faltstrom, P., Hoffman, P., and A. Costello, [RFC3490] Faltstrom, P., Hoffman, P., and A. Costello,
"Internationalizing Domain Names in Applications (IDNA)", "Internationalizing Domain Names in Applications (IDNA)",
RFC 3490, March 2003. RFC 3490, March 2003.
[RFC3491] Hoffman, P. and M. Blanchet, "Nameprep: A Stringprep
Profile for Internationalized Domain Names (IDN)",
RFC 3491, March 2003.
[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.
[RFC4422] Melnikov, A. and K. Zeilenga, "Simple Authentication and [RFC4422] Melnikov, A. and K. Zeilenga, "Simple Authentication and
Security Layer (SASL)", RFC 4422, June 2006. Security Layer (SASL)", RFC 4422, June 2006.
[RFC4510] Zeilenga, K., "Lightweight Directory Access Protocol [RFC4510] Zeilenga, K., "Lightweight Directory Access Protocol
(LDAP): Technical Specification Road Map", RFC 4510, (LDAP): Technical Specification Road Map", RFC 4510,
June 2006. June 2006.
skipping to change at page 26, line 37 skipping to change at page 26, line 17
<http://unicode.org/reports/tr9/>. <http://unicode.org/reports/tr9/>.
[UTR36] The Unicode Consortium, "Unicode Technical Report #36: [UTR36] The Unicode Consortium, "Unicode Technical Report #36:
Unicode Security Considerations", August 2010, Unicode Security Considerations", August 2010,
<http://unicode.org/reports/tr36/>. <http://unicode.org/reports/tr36/>.
[UTR39] The Unicode Consortium, "Unicode Technical Report #39: [UTR39] The Unicode Consortium, "Unicode Technical Report #39:
Unicode Security Mechanisms", August 2010, Unicode Security Mechanisms", August 2010,
<http://unicode.org/reports/tr39/>. <http://unicode.org/reports/tr39/>.
[XMPP-ADDR]
Saint-Andre, P., "Extensible Messaging and Presence
Protocol (XMPP): Address Format",
draft-saintandre-xmpp-6122bis-02 (work in progress),
August 2011.
URIs URIs
[1] <http://unicode.org/Public/UNIDATA/PropertyAliases.txt> [1] <http://unicode.org/Public/UNIDATA/PropertyAliases.txt>
[2] <http://unicode.org/Public/UNIDATA/DerivedCoreProperties.txt> [2] <http://unicode.org/Public/UNIDATA/DerivedCoreProperties.txt>
Authors' Addresses Appendix A. Codepoints 0x0000 - 0x10FFFF
Marc Blanchet To follow.
Viagenie
2600 boul. Laurier, suite 625
Quebec, QC G1V 4W1
Canada
Email: Marc.Blanchet@viagenie.ca If one applies the rules (Section 7) to the code points 0x0000 to
URI: http://www.viagenie.ca/ 0x10FFFF to Unicode 6.1, the result is as follows.
NOTE: This list is non-normative, and only included for illustrative
purposes. Specifically, what is displayed in the third column is not
necessarily the formal name of the code point (as defined in
[UNICODE]). There are differences, for example with regard to the
code points that have the code point value as part of the name
(example: CJK UNIFIED IDEOGRAPH-4E00) and the naming of Hangul
syllables. However, for many code points, what you see is the
official name.
A.1. Codepoints in Unicode Character Database (UCD) format
In progress...
0000..001F ; DISALLOWED # <control>
0020 ; FREE_PVAL, NAME_DIS # SPACE
0021..007E ; PVALID # EXCLAMATION MARK .. TILDE
007F..009F ; DISALLOWED # <control>
00A0..00A9 ; FREE_PVAL, NAME_DIS # NO-BREAK SPACE .. COPYRIGHT SIGN
00AA ; PVALID # FEMININE ORDINAL INDICATOR
00AB..00AC ; FREE_PVAL, NAME_DIS # NO-BREAK SPACE .. NOT SIGN
00AD ; DISALLOWED # SOFT HYPHEN
00AE..00B6 ; FREE_PVAL, NAME_DIS # REGISTERED SIGN .. PILCROW SIGN
00B7 ; CONTEXTO # MIDDLE DOT
00B8..00BF ; FREE_PVAL, NAME_DIS # CEDILLA..INVERTED QUESTION IND
00C0..00D6 ; PVALID # LAT CAP LET A W GRAV..LAT CAP O
00D7 ; FREE_PVAL, NAME_DIS # MULTIPLICATION SIGN
00D8..00F6 ; PVALID # LAT CAP LET O W STROKE..LAT SM
00F7 ; FREE_PVAL, NAME_DIS # DIVISION SIGN
00F8..0131 ; PVALID # LAT SM LET O W STROKE..LAT SM LET
0132..0133 ; FREE_PVAL, NAME_DIS # LAT CAP LIG IJ..LAT SM LIB IJ
0134..013E ; PVALID # LAT CAP LET J W CIRCUM..LAT SM LET
013F..0140 ; FREE_PVAL, NAME_DIS # LAT CAP LET L W MID DOT..LAT SM LET
0141..0148 ; PVALID # LAT CAP LET L W STROKE..LAT SM LET
0149 ; FREE_PVAL, NAME_DIS # LAT SM LET N PRECEDED BY APOSTROPHE
014A..017E ; PVALID # LAT CAP LET ENG..LAT SM LET Z W CA
017F ; FREE_PVAL, NAME_DIS # LATIN SMALL LETTER LONG S
0180..01C3 ; PVALID # LAT SM LET B W STROKE..LAT LET RETR
01C4..01CC ; FREE_PVAL, NAME_DIS # LAT CAP LET DZ W CARON..LATIN SM
01CD..01F0 ; PVALID # LAT CAP LET A W CARON..LAT SM LET J
01F1..01F3 ; FREE_PVAL, NAME_DIS # LAT CAP LET DZ..LAT SM LET DZ
01F4..02AF ; PVALID # LAT CAP LET G WITH ACUTE..LAT SM
02B0..02B8 ; FREE_PVAL, NAME_DIS # MOD LET SM H..MOD LET SM Y
02B9..02C1 ; PVALID # MOD LET PRIME..MOD LET REV GLOT ST
02C2..02C5 ; FREE_PVAL, NAME_DIS # MOD LET L ARROW..MOD LET D ARROW
02C6..02D1 ; PVALID # MOD LET CIRCUM ACC..MOD LET HALF TR
02D2..02EB ; FREE_PVAL, NAME_DIS # MOD LET CENT R HALF RING..MOD LET Y
02EC ; PVALID # MODIFIER LETTER VOICING
02ED ; FREE_PVAL, NAME_DIS # MODIFIER LETTER UNASPIRATED
02EE ; PVALID # MODIFIER LETTER DOUBLE APOSTROPHE
02EF..02FF ; FREE_PVAL, NAME_DIS # MOD LET LOW D ARR..MOD LET LOW L AR
0300..0374 ; PVALID # COMB GRAVE ACCENT..GREEK NUM SIGN
0375 ; CONTEXTO # GREEK LOWER NUMERAL SIGN
0376..0377 ; PVALID # GR CAP LET PAMPHYLIAN DIGAMMA..GR S
0378..0379 ; UNASSIGNED # <reserved>..<reserved>
037A..037D ; PVALID # GR YPOGEGRAMMENI..GR SM REV DOT LUN
037E ; FREE_PVAL, NAME_DIS # GREEK QUESTION MARK
037F..0383 ; UNASSIGNED # <reserved>..<reserved>
0384..0385 ; FREE_PVAL, NAME_DIS # GREEK TONOS..GREEK DIALYTIKA TONOS
0386 ; PVALID # GR CAP LET ALPHA WITH TONOS
0387 ; FREE_PVAL, NAME_DIS # GREEK ANO TELEIA
0388..038A ; PVALID # GR CAP LET EPSILON W TONOS..GR CAP
038B ; UNASSIGNED # <reserved>
038C ; PVALID # GR CAP LET OMICRON WITH TONOS
038D ; UNASSIGNED # <reserved>
038E..03A1 ; PVALID # GR CAP LET EPSILON W TONOS..GR CAP
03A2 ; UNASSIGNED # <reserved>
03A3..03CF ; PVALID # GREEK CAPITAL LETTER SIGMA..GR CAP
03D0..03D2 ; FREE_PVAL, NAME_DIS # GR BETA SYMBOL..GR UPSILON W HOOK
03D3..03D4 ; PVALID # GR UPSILON W ACUTE AND HOOK..GR UP
03D5..03D6 ; FREE_PVAL, NAME_DIS # GR PHI SYMBOL..GR PI SYMBOL
03D7..03EF ; PVALID # GR KAI SYMBOL..COPTIC SM LET DEI
03F0..03F2 ; FREE_PVAL, NAME_DIS # GR KAPPA SYMBOL..GR LUNATE SIGMA
03F3 ; PVALID # GREEK LETTER YOT
03F4..03F6 ; FREE_PVAL, NAME_DIS # GR CAP THETA..GR REV LUNATE EPSILON
03F7..03F8 ; PVALID # GR CAP LET SHO..GR SM LET SHO
03F9 ; FREE_PVAL, NAME_DIS # GREEK CAPITAL LUNATE SIGMA SYMBOL
03FA..0481 ; PVALID # GR CAP LET SAN..CYR SML LET KOPPA
0482 ; FREE_PVAL, NAME_DIS # CYRILLIC THOUSANDS SIGN
0483..0487 ; PVALID # COMB CYR TITLO..COMB CYRILLIC POK
0488..048A ; FREE_PVAL, NAME_DIS # COMB CYR HUNDRED THOUSANDS SIGN..C
048B..0527 ; PVALID # CYR SM LET SHORT I WITH TAIL..CYR S
0528..0530 ; UNASSIGNED # <reserved>..<reserved>
0531..0556 ; PVALID # ARM CAP LET AYB..ARM CAP LET FEH
0557..0558 ; UNASSIGNED # <reserved>..<reserved>
0559 ; PVALID # ARM MOD LET LEFT HALF RING
055A..055F ; FREE_PVAL, NAME_DIS # ARM APOS..ARM ABBREV
0560 ; UNASSIGNED # <reserved>
0561..0586 ; PVALID # ARM SM LET AYB..ARMENIAN SMALL LE
0587 ; FREE_PVAL, NAME_DIS # ARM SM LIGATURE ECH YIWN
0588 ; UNASSIGNED # <reserved>
0589..058A ; FREE_PVAL, NAME_DIS # ARMENIAN FULL STOP..ARMENIAN HYPHEN
058B..058E ; UNASSIGNED # <reserved>..<reserved>
058F ; FREE_PVAL, NAME_DIS # ARMENIAN DRAM SIGN
0590 ; UNASSIGNED # <reserved>
0591..05BD ; PVALID # HEBR ACC ETNAHTA..HEBR PNT ME
05BE ; FREE_PVAL, NAME_DIS # HEBR PUNCT MAQAF
05BF ; PVALID # HEBR PNT RAFE
05C0 ; FREE_PVAL, NAME_DIS # HEBR PUNCT PASEQ
05C1..05C2 ; PVALID # HEBR PNT SHIN DOT..HEBR PNT SIN DOT
05C3 ; FREE_PVAL, NAME_DIS # HEBR PUNCT SOF PASUQ
05C4..05C5 ; PVALID # HEBR MARK UP DOT..HEBR MARK LOW DOT
05C6 ; FREE_PVAL, NAME_DIS # HEBR PUNCT NUN HAFUKHA
05C7 ; PVALID # HEBR PNT QAMATS QATAN
05C8..05CF ; UNASSIGNED # <reserved>..<reserved>
05D0..05EA ; PVALID # HEBR LET ALEF..HEBR LET TAV
05EB..05EF ; UNASSIGNED # <reserved>..<reserved>
05F0..05F2 ; PVALID # HEBR LIG YIDDISH DOUBLE VAV..HEBR L
05F3..05F4 ; CONTEXTO # HEBR PUNCT GERESH..HEBR PUNCTUATIO
05F5..05FF ; UNASSIGNED # <reserved>..<reserved>
0600..0604 ; DISALLOWED # ARABIC NUMBER SIGN..ARABIC SIGN SAM
0605 ; UNASSIGNED # <reserved>..<reserved>
0606..060F ; FREE_PVAL, NAME_DIS # AR-IND CUBE ROOT..ARABIC SIGN MISRA
0610..061A ; PVALID # ARABIC SIGN SALLALLAHOU ALAYHE ..AR
061B ; FREE_PVAL, NAME_DIS # ARABIC SEMICOLON
061C..061D ; UNASSIGNED # <reserved>..<reserved>
061E..061F ; FREE_PVAL, NAME_DIS # ARABIC TRIPLE DOT PUNCT MARK..ARABI
0620 ; UNASSIGNED # <reserved>
0621..063F ; PVALID # ARABIC LET HAMZA..ARABIC LET FARSI
0640 ; DISALLOWED # ARABIC TATWEEL
0641..065F ; PVALID # ARABIC LET FEH..ARABIC WAVY HAMZA B
0660..0669 ; CONTEXTO # AR-IND DIG ZERO..AR-IND DIG
066A..066D ; FREE_PVAL, NAME_DIS # ARABIC PCT SIGN..ARABIC FIVE PNTED
066E..0674 ; PVALID # ARABIC LET DOTLESS BEH..ARABIC LET
0675..0678 ; FREE_PVAL, NAME_DIS # ARABIC LET HIGH HAMZA ALEF..ARABIC
0679..06D3 ; PVALID # ARABIC LET TTEH..ARABIC LET YEH BAR
06D4 ; FREE_PVAL, NAME_DIS # ARABIC FULL STOP
06D5..06DC ; PVALID # ARABIC LET AE..ARABIC SM HIGH SEEN
06DD ; DISALLOWED # ARABIC END OF AYAH
06DE ; FREE_PVAL, NAME_DIS # ARABIC START OF RUB EL HIZB
06DF..06E8 ; PVALID # ARABIC SM HIGH ROUNDED ZERO..ARABI
06E9 ; FREE_PVAL, NAME_DIS # ARABIC PLACE OF SAJDAH
06EA..06EF ; PVALID # ARABIC EMPTY CENTRE LOW STOP..ARABI
06F0..06F9 ; CONTEXTO # EXT AR-IND DIG ZERO..EXT A
06FA..06FF ; PVALID # ARABIC LET SHEEN W DOT BEL..ARABIC
0700..070D ; FREE_PVAL, NAME_DIS # SYR END OF PARA..SYR HARKLEAN AST
070E ; UNASSIGNED # <reserved>
070F ; DISALLOWED # SYR ABBR MARK
0710..07B1 ; PVALID # SYR LET ALAPH..THAANA LET N
07B2..07BF ; UNASSIGNED # <reserved>..<reserved>
07C0..07F5 ; PVALID # NKO DIG ZERO..NKO LOW TONE APOS
07F6..07FA ; FREE_PVAL, NAME_DIS # NKO SYMBOL OO DENNEN..NKO LAJANYA
07FB..07FF ; UNASSIGNED # <reserved>..<reserved>
0800..082D ; PVALID # SAMAR LET ALAF..SAMAR MARK NEQUDA
082E..082F ; UNASSIGNED # <reserved>..<reserved>
0830..083E ; FREE_PVAL, NAME_DIS # SAMAR PUNCT NEQUDAA..SAMAR PUN
083F ; UNASSIGNED # <reserved>
0840..085B ; PVALID # MANDAIC LET HALQA..MANDAIC GEM
085C..085D ; UNASSIGNED # <reserved>..<reserved>
085E ; FREE_PVAL, NAME_DIS # MANDAIC PUNCTUATION
08A0..08AC ; PVALID # ARABIC LET BEH W SM V BEL..ARABIC
08AD..08E3 ; UNASSIGNED # <reserved>..<reserved>
08E4..08FE ; PVALID # ARABIC CURLY FATHA..ARABIC DAMMA W
08FF ; UNASSIGNED # <reserved>
0900..0963 ; PVALID # DEVAN SIGN INV CANDRABINDU..DEVAN V
0964..0965 ; FREE_PVAL, NAME_DIS # DEVAN DANDA..DEVAN DOUBLE DANDA
0966..096F ; PVALID # DEVAN DIG ZERO..DEVAN DIG NINE
0970 ; FREE_PVAL, NAME_DIS # DEVAN ABBR SIGN
0971..097F ; PVALID # DEVAN SIGN HIGH SPACING DOT..DEVAN
0980 ; UNASSIGNED # <reserved>
0981..0983 ; PVALID # BENG SIGN CANDRABINDU..BENG SIGN V
0984 ; UNASSIGNED # <reserved>
0985..098C ; PVALID # BENG LET A..BENG LET VOCALIC L
098D..098E ; UNASSIGNED # <reserved>..<reserved>
098F..0990 ; PVALID # BENG LET E..BENG LET AI
0991..0992 ; UNASSIGNED # <reserved>..<reserved>
0993..09A8 ; PVALID # BENG LET O..BENG LET NA
09A9 ; UNASSIGNED # <reserved>
09AA..09B0 ; PVALID # BENG LET PA..BENG LET RA
09B1 ; UNASSIGNED # <reserved>
09B2 ; PVALID # BENG LET LA
09B3..09B5 ; UNASSIGNED # <reserved>..<reserved>
09B6..09B9 ; PVALID # BENG LET SHA..BENG LET HA
09BA..09BB ; UNASSIGNED # <reserved>..<reserved>
09BC..09C4 ; PVALID # BENG SIGN NUKTA..BENG VOWEL SIGN VO
09C5..09C6 ; UNASSIGNED # <reserved>..<reserved>
09C7..09C8 ; PVALID # BENG VOWEL SIGN E..BENG VOWEL SIGN
09C9..09CA ; UNASSIGNED # <reserved>..<reserved>
09CB..09CE ; PVALID # BENG VOWEL SIGN O..BENG LET KHANDA
09CF..09D6 ; UNASSIGNED # <reserved>..<reserved>
09D7 ; PVALID # BENG AU LENGTH MARK
09D8..09DB ; UNASSIGNED # <reserved>..<reserved>
09DC..09DD ; PVALID # BENG LET RRA..BENG LET RHA
09DE ; UNASSIGNED # <reserved>
09DF..09E3 ; PVALID # BENG LET YYA..BENG VOWEL SIG
09E4..09E5 ; UNASSIGNED # <reserved>..<reserved>
09E6..09F1 ; PVALID # BENG DIG ZERO..BENG LET RA W L
09F2..09F3 ; FREE_PVAL, NAME_DIS # BENG RUPEE MARK..BENG RUPEE SIGN
09F4..09FB ; DISALLOWED # BENG CURR NUM ONE..BENG GANDA MARK
09FC..0A00 ; UNASSIGNED # <reserved>..<reserved>
0A01..10FFFF; TBD!
Appendix B. Acknowledgements
The authors would like to acknowledge the comments and contributions
of the following individuals: David Black, Mark Davis, Alan DeKok,
Martin Duerst, Patrik Faltstrom, Ted Hardie, Joe Hildebrand, Paul
Hoffman, Jeffrey Hutzelman, Simon Josefsson, John Klensin, Alexey
Melnikov, Yoav Nir, Mike Parker, Pete Resnick, Andrew Sullivan, Dave
Thaler, and Yoshiro Yoneya.
Some algorithms and textual descriptions have been borrowed from
[RFC5892]. Some text regarding security has been borrowed from
[RFC5890] and [I-D.ietf-xmpp-6122bis].
Authors' Addresses
Peter Saint-Andre Peter Saint-Andre
Cisco Cisco Systems, Inc.
1899 Wyknoop Street, Suite 600 1899 Wynkoop Street, Suite 600
Denver, CO 80202 Denver, CO 80202
USA USA
Phone: +1-303-308-3282 Phone: +1-303-308-3282
Email: psaintan@cisco.com Email: psaintan@cisco.com
Marc Blanchet
Viagenie
246 Aberdeen
Quebec, QC G1R 2E1
Canada
Email: Marc.Blanchet@viagenie.ca
URI: http://www.viagenie.ca/
 End of changes. 61 change blocks. 
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