libwind from Assar. stringprep library supporting nameprep, saslprep and ldapprep
git-svn-id: svn://svn.h5l.se/heimdal/trunk/heimdal@22551 ec53bebd-3082-4978-b11e-865c3cabbd6b
This commit is contained in:
Love Hörnquist Åstrand
395
lib/wind/rfc3491.txt
Normal file
395
lib/wind/rfc3491.txt
Normal file
@@ -0,0 +1,395 @@
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
Network Working Group P. Hoffman
|
||||
Request for Comments: 3491 IMC & VPNC
|
||||
Category: Standards Track M. Blanchet
|
||||
Viagenie
|
||||
March 2003
|
||||
|
||||
|
||||
Nameprep: A Stringprep Profile for
|
||||
Internationalized Domain Names (IDN)
|
||||
|
||||
Status of this Memo
|
||||
|
||||
This document specifies an Internet standards track protocol for the
|
||||
Internet community, and requests discussion and suggestions for
|
||||
improvements. Please refer to the current edition of the "Internet
|
||||
Official Protocol Standards" (STD 1) for the standardization state
|
||||
and status of this protocol. Distribution of this memo is unlimited.
|
||||
|
||||
Copyright Notice
|
||||
|
||||
Copyright (C) The Internet Society (2003). All Rights Reserved.
|
||||
|
||||
Abstract
|
||||
|
||||
This document describes how to prepare internationalized domain name
|
||||
(IDN) labels in order to increase the likelihood that name input and
|
||||
name comparison work in ways that make sense for typical users
|
||||
throughout the world. This profile of the stringprep protocol is
|
||||
used as part of a suite of on-the-wire protocols for
|
||||
internationalizing the Domain Name System (DNS).
|
||||
|
||||
1. Introduction
|
||||
|
||||
This document specifies processing rules that will allow users to
|
||||
enter internationalized domain names (IDNs) into applications and
|
||||
have the highest chance of getting the content of the strings
|
||||
correct. It is a profile of stringprep [STRINGPREP]. These
|
||||
processing rules are only intended for internationalized domain
|
||||
names, not for arbitrary text.
|
||||
|
||||
This profile defines the following, as required by [STRINGPREP].
|
||||
|
||||
- The intended applicability of the profile: internationalized
|
||||
domain names processed by IDNA.
|
||||
|
||||
- The character repertoire that is the input and output to
|
||||
stringprep: Unicode 3.2, specified in section 2.
|
||||
|
||||
|
||||
|
||||
|
||||
Hoffman & Blanchet Standards Track [Page 1]
|
||||
|
||||
RFC 3491 IDN Nameprep March 2003
|
||||
|
||||
|
||||
- The mappings used: specified in section 3.
|
||||
|
||||
- The Unicode normalization used: specified in section 4.
|
||||
|
||||
- The characters that are prohibited as output: specified in section
|
||||
5.
|
||||
|
||||
- Bidirectional character handling: specified in section 6.
|
||||
|
||||
1.1 Interaction of protocol parts
|
||||
|
||||
Nameprep is used by the IDNA [IDNA] protocol for preparing domain
|
||||
names; it is not designed for any other purpose. It is explicitly
|
||||
not designed for processing arbitrary free text and SHOULD NOT be
|
||||
used for that purpose. Nameprep is a profile of Stringprep
|
||||
[STRINGPREP]. Implementations of Nameprep MUST fully implement
|
||||
Stringprep.
|
||||
|
||||
Nameprep is used to process domain name labels, not domain names.
|
||||
IDNA calls nameprep for each label in a domain name, not for the
|
||||
whole domain name.
|
||||
|
||||
1.2 Terminology
|
||||
|
||||
The key words "MUST", "MUST NOT", "SHOULD", "SHOULD NOT", and "MAY"
|
||||
in this document are to be interpreted as described in BCP 14, RFC
|
||||
2119 [RFC2119].
|
||||
|
||||
2. Character Repertoire
|
||||
|
||||
This profile uses Unicode 3.2, as defined in [STRINGPREP] Appendix A.
|
||||
|
||||
3. Mapping
|
||||
|
||||
This profile specifies mapping using the following tables from
|
||||
[STRINGPREP]:
|
||||
|
||||
Table B.1
|
||||
Table B.2
|
||||
|
||||
4. Normalization
|
||||
|
||||
This profile specifies using Unicode normalization form KC, as
|
||||
described in [STRINGPREP].
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
Hoffman & Blanchet Standards Track [Page 2]
|
||||
|
||||
RFC 3491 IDN Nameprep March 2003
|
||||
|
||||
|
||||
5. Prohibited Output
|
||||
|
||||
This profile specifies prohibiting using the following tables from
|
||||
[STRINGPREP]:
|
||||
|
||||
Table C.1.2
|
||||
Table C.2.2
|
||||
Table C.3
|
||||
Table C.4
|
||||
Table C.5
|
||||
Table C.6
|
||||
Table C.7
|
||||
Table C.8
|
||||
Table C.9
|
||||
|
||||
IMPORTANT NOTE: This profile MUST be used with the IDNA protocol.
|
||||
The IDNA protocol has additional prohibitions that are checked
|
||||
outside of this profile.
|
||||
|
||||
6. Bidirectional characters
|
||||
|
||||
This profile specifies checking bidirectional strings as described in
|
||||
[STRINGPREP] section 6.
|
||||
|
||||
7. Unassigned Code Points in Internationalized Domain Names
|
||||
|
||||
If the processing in [IDNA] specifies that a list of unassigned code
|
||||
points be used, the system uses table A.1 from [STRINGPREP] as its
|
||||
list of unassigned code points.
|
||||
|
||||
8. References
|
||||
|
||||
8.1 Normative References
|
||||
|
||||
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
|
||||
Requirement Levels", BCP 14, RFC 2119, March 1997.
|
||||
|
||||
[STRINGPREP] Hoffman, P. and M. Blanchet, "Preparation of
|
||||
Internationalized Strings ("stringprep")", RFC 3454,
|
||||
December 2002.
|
||||
|
||||
[IDNA] Faltstrom, P., Hoffman, P. and A. Costello,
|
||||
"Internationalizing Domain Names in Applications
|
||||
(IDNA)", RFC 3490, March 2003.
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
Hoffman & Blanchet Standards Track [Page 3]
|
||||
|
||||
RFC 3491 IDN Nameprep March 2003
|
||||
|
||||
|
||||
8.2 Informative references
|
||||
|
||||
[STD13] Mockapetris, P., "Domain names - concepts and
|
||||
facilities", STD 13, RFC 1034, and "Domain names -
|
||||
implementation and specification", STD 13, RFC 1035,
|
||||
November 1987.
|
||||
|
||||
9. Security Considerations
|
||||
|
||||
The Unicode and ISO/IEC 10646 repertoires have many characters that
|
||||
look similar. In many cases, users of security protocols might do
|
||||
visual matching, such as when comparing the names of trusted third
|
||||
parties. Because it is impossible to map similar-looking characters
|
||||
without a great deal of context such as knowing the fonts used,
|
||||
stringprep does nothing to map similar-looking characters together
|
||||
nor to prohibit some characters because they look like others.
|
||||
|
||||
Security on the Internet partly relies on the DNS. Thus, any change
|
||||
to the characteristics of the DNS can change the security of much of
|
||||
the Internet.
|
||||
|
||||
Domain names are used by users to connect to Internet servers. The
|
||||
security of the Internet would be compromised if a user entering a
|
||||
single internationalized name could be connected to different servers
|
||||
based on different interpretations of the internationalized domain
|
||||
name.
|
||||
|
||||
Current applications might assume that the characters allowed in
|
||||
domain names will always be the same as they are in [STD13]. This
|
||||
document vastly increases the number of characters available in
|
||||
domain names. Every program that uses "special" characters in
|
||||
conjunction with domain names may be vulnerable to attack based on
|
||||
the new characters allowed by this specification.
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
Hoffman & Blanchet Standards Track [Page 4]
|
||||
|
||||
RFC 3491 IDN Nameprep March 2003
|
||||
|
||||
|
||||
10. IANA Considerations
|
||||
|
||||
This is a profile of stringprep. It has been registered by the IANA
|
||||
in the stringprep profile registry
|
||||
(www.iana.org/assignments/stringprep-profiles).
|
||||
|
||||
Name of this profile:
|
||||
Nameprep
|
||||
|
||||
RFC in which the profile is defined:
|
||||
This document.
|
||||
|
||||
Indicator whether or not this is the newest version of the
|
||||
profile:
|
||||
This is the first version of Nameprep.
|
||||
|
||||
11. Acknowledgements
|
||||
|
||||
Many people from the IETF IDN Working Group and the Unicode Technical
|
||||
Committee contributed ideas that went into this document.
|
||||
|
||||
The IDN Nameprep design team made many useful changes to the
|
||||
document. That team and its advisors include:
|
||||
|
||||
Asmus Freytag
|
||||
Cathy Wissink
|
||||
Francois Yergeau
|
||||
James Seng
|
||||
Marc Blanchet
|
||||
Mark Davis
|
||||
Martin Duerst
|
||||
Patrik Faltstrom
|
||||
Paul Hoffman
|
||||
|
||||
Additional significant improvements were proposed by:
|
||||
|
||||
Jonathan Rosenne
|
||||
Kent Karlsson
|
||||
Scott Hollenbeck
|
||||
Dave Crocker
|
||||
Erik Nordmark
|
||||
Matitiahu Allouche
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
Hoffman & Blanchet Standards Track [Page 5]
|
||||
|
||||
RFC 3491 IDN Nameprep March 2003
|
||||
|
||||
|
||||
12. Authors' Addresses
|
||||
|
||||
Paul Hoffman
|
||||
Internet Mail Consortium and VPN Consortium
|
||||
127 Segre Place
|
||||
Santa Cruz, CA 95060 USA
|
||||
|
||||
EMail: paul.hoffman@imc.org and paul.hoffman@vpnc.org
|
||||
|
||||
|
||||
Marc Blanchet
|
||||
Viagenie inc.
|
||||
2875 boul. Laurier, bur. 300
|
||||
Ste-Foy, Quebec, Canada, G1V 2M2
|
||||
|
||||
EMail: Marc.Blanchet@viagenie.qc.ca
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
Hoffman & Blanchet Standards Track [Page 6]
|
||||
|
||||
RFC 3491 IDN Nameprep March 2003
|
||||
|
||||
|
||||
13. Full Copyright Statement
|
||||
|
||||
Copyright (C) The Internet Society (2003). All Rights Reserved.
|
||||
|
||||
This document and translations of it may be copied and furnished to
|
||||
others, and derivative works that comment on or otherwise explain it
|
||||
or assist in its implementation may be prepared, copied, published
|
||||
and distributed, in whole or in part, without restriction of any
|
||||
kind, provided that the above copyright notice and this paragraph are
|
||||
included on all such copies and derivative works. However, this
|
||||
document itself may not be modified in any way, such as by removing
|
||||
the copyright notice or references to the Internet Society or other
|
||||
Internet organizations, except as needed for the purpose of
|
||||
developing Internet standards in which case the procedures for
|
||||
copyrights defined in the Internet Standards process must be
|
||||
followed, or as required to translate it into languages other than
|
||||
English.
|
||||
|
||||
The limited permissions granted above are perpetual and will not be
|
||||
revoked by the Internet Society or its successors or assigns.
|
||||
|
||||
This document and the information contained herein is provided on an
|
||||
"AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
|
||||
TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
|
||||
BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
|
||||
HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
|
||||
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
|
||||
|
||||
Acknowledgement
|
||||
|
||||
Funding for the RFC Editor function is currently provided by the
|
||||
Internet Society.
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
Hoffman & Blanchet Standards Track [Page 7]
|
||||
|
||||
Reference in New Issue
Block a user