This document is obsolete. Please
refer to RFC 7564.
Network Working Group P. Hoffman Request for Comments: 3454 IMC & VPNC Category: Standards Track M. Blanchet Viagenie December 2002
Preparation of Internationalized Strings ("stringprep")
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 (2002). All Rights Reserved.
Abstract
This document describes a framework for preparing Unicode text strings in order to increase the likelihood that string input and string comparison work in ways that make sense for typical users throughout the world. The stringprep protocol is useful for protocol identifier values, company and personal names, internationalized domain names, and other text strings.
This document does not specify how protocols should prepare text strings. Protocols must create profiles of stringprep in order to fully specify the processing options.
Table of Contents
1. Introduction....................................................3 1.1 Terminology..................................................4 1.2 Using stringprep in protocols................................4 2. Preparation Overview............................................6 3. Mapping.........................................................7 3.1 Commonly mapped to nothing...................................7 3.2 Case folding.................................................8 4. Normalization...................................................9 5. Prohibited Output..............................................10 5.1 Space characters............................................11 5.2 Control characters..........................................11 5.3 Private use.................................................12
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5.4 Non-character code points...................................12 5.5 Surrogate codes.............................................13 5.6 Inappropriate for plain text................................13 5.7 Inappropriate for canonical representation..................13 5.8 Change display properties or deprecated.....................13 5.9 Tagging characters..........................................14 6. Bidirectional Characters.......................................14 7. Unassigned Code Points in Stringprep Profiles..................15 7.1 Categories of code points...................................16 7.2 Reasons for difference between stored strings and queries...17 7.3 Versions of applications and stored strings.................18 8. References.....................................................19 8.1 Normative references........................................19 8.2 Informative references......................................19 9. Security Considerations........................................19 9.1 Stringprep-specific security considerations.................19 9.2 Generic Unicode security considerations.....................20 10. IANA Considerations...........................................21 11. Acknowledgements..............................................22 A. Unicode repertoires............................................23 A.1 Unassigned code points in Unicode 3.2.......................23 B. Mapping Tables.................................................31 B.1 Commonly mapped to nothing..................................31 B.2 Mapping for case-folding used with NFKC.....................32 B.3 Mapping for case-folding used with no normalization.........61 C. Prohibition tables.............................................78 C.1 Space characters............................................78 C.1.1 ASCII space characters..................................78 C.1.2 Non-ASCII space characters..............................79 C.2 Control characters..........................................79 C.2.1 ASCII control characters................................79 C.2.2 Non-ASCII control characters............................79 C.3 Private use.................................................80 C.4 Non-character code points...................................80 C.5 Surrogate codes.............................................80 C.6 Inappropriate for plain text................................80 C.7 Inappropriate for canonical representation..................81 C.8 Change display properties or are deprecated.................81 C.9 Tagging characters..........................................81 D. Bidirectional tables...........................................81 D.1 Characters with bidirectional property "R" or "AL"..........81 D.2 Characters with bidirectional property "L"..................82 Authors' Addresses................................................90 Full Copyright Statement..........................................91
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Application programs can display text in many different ways. Similarly, a user can enter text into an application program in a myriad of fashions. Internationalized text (that is, text that is not restricted to the narrow set of US-ASCII characters) has many input and display behaviors that make it difficult to compare text in a consistent fashion.
This document specifies a framework of processing rules for Unicode text. Other protocols can create profiles of these rules; these profiles will allow users to enter internationalized text strings in applications and have the highest chance of getting the content of the strings correct. In this case, "correct" means that if two different people enter what they think is the same string into two different input mechanisms, the strings should match on a character- by-character basis.
This framework does not describe how data is transcoded from other character sets into Unicode. In systems that uses non-Unicode character sets, the transcoding algorithm is a critical part of enabling secure and "correct" operation of internationalized text strings.
In addition to helping string matching, profiles of stringprep can also exclude characters that should not normally appear in text that is used in the protocol. The profile can prevent such characters by changing the characters to be excluded to other characters, by removing those characters, or by causing an error if the characters would appear in the output. For example, because the backspace character can cause unpredictable display results, a profile can specify that a string containing a backspace character would cause an error.
A profile of stringprep converts a single string of input characters to a string of output characters, or returns an error if the output string would contain a prohibited character. Stringprep profiles cannot both emit a string and return an error.
Stringprep profiles cannot account for all of the variations that might occur or that a user might expect. In particular, a profile will not be able to account for choice of spellings in all languages for all scripts because the number of alternative spellings of words and phrases is immense. Users would probably expect all spelling equivalents to be made equivalent, or none of them to be. Examples of spelling equivalents include "theater" vs. "theatre", and "hemoglobin" vs. "h<U+00E6>moglobin" in American vs. British English. Other examples are simplified Chinese spellings of names (for
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example,"<U+7EDF><U+4E00><U+7801>") vs. the equivalent traditional Chinese spelling (for example, "<U+7D71><U+4E00><U+78BC>"). Language-specific equivalences such as "Aepfel" vs. "<U+00C4>pfel", which are sometimes considered equivalent in German, may not be considered equivalent in other languages.
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in BCP 14, RFC 2119 [RFC2119].
Note: A glossary of terms used in Unicode and ISO/IEC 10646 can be found in [Glossary]. Information on the 10646/Unicode character encoding model can be found in [CharModel].
Character names in this document use the notation for code points and names from the Unicode Standard [Unicode3.2] and ISO/IEC 10646 [ISO10646]. For example, the letter "a" may be represented as either "U+0061" or "LATIN SMALL LETTER A". In the lists of mappings and the prohibited characters, the "U+" is left off to make the lists easier to read. The comments for character ranges are shown in square brackets (such as "[CONTROL CHARACTERS]") and do not come from the standards.
The stringprep protocol does not stand on its own; it has to be used by other protocols at precisely-defined places in those other protocols. For example, a protocol that has strings that come from the entire ISO/IEC 10646 [ISO10646] character repertoire might specify that only strings that have been processed with a particular profile of stringprep are legal. Another example would be a protocol that does string comparison as a step in the protocol; that protocol might specify that such comparison is done only after processing the strings with a specific profile of stringprep.
When two protocols that use different profiles of stringprep interoperate, there may be conflict about what characters are and are not allowed in the final string. Thus, protocol developers should strongly consider re-using existing profiles of stringprep.
When developers wish to allow users as wide of a range of characters as possible in input text strings, they should, where possible, cause stringprep to convert characters from the input string to a canonical form instead of prohibiting them.
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Although it would be easy to use the stringprep process to "correct" perceived mis-features or bugs in the current character standards, stringprep profiles SHOULD NOT do so.
A profile of stringprep can create tables different from those in the appendixes of this document, but it will be an exception when they do. The intention of stringprep is to define the tables and have the profiles of stringprep select among those defined tables.
A profile of stringprep MUST include all of the following:
- The intended applicability of the profile
- The character repertoire that is the input and output to stringprep (which is Unicode 3.2 for this version of stringprep)
- The mapping tables from this document used (as described in section 3)
- Any additional mapping tables specific to the profile
- The Unicode normalization used, if any (as described in section 4)
- The tables from this document of characters that are prohibited as output (as described in section 5)
- The bidirectional string testing used, if any (as described in section 6)
- Any additional characters that are prohibited as output specific to the profile
Each profile MUST state the character repertoire on which the profile will operate. Appendix A lists the Unicode repertoires that can be selected. No repertoire is ever complete, and it is expected that characters will be added to the Unicode repertoire for the foreseeable future. Section 7 of this document describes how to handle characters that are assigned in later versions of the Unicode repertories. Subsections of appendix A also list unassigned code points for each repertoire.
This document is for Unicode version 3.2, and should not be considered to automatically apply to later Unicode versions. The IETF, through an explicit standards action, may update this document as appropriate to handle later Unicode versions.
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This document lists the unassigned code points in the range 0 to 10FFFF for Unicode 3.2 in appendix A. The list in appendix AMUST be used by implementations of this specification. If there are any discrepancies between the list in appendix A and the Unicode 3.2 specification, the list in appendix A always takes precedence.
Each profile of stringprep MUST be registered with IANA. The registration procedure is described in the IANA Considerations appendix; basically, the IESG must review each profile of stringprep. Protocol developers are strongly encouraged to look through the IANA profile registry when creating new profiles for stringprep, and to re-use logic from earlier profiles where possible in new profiles. In some cases, an existing profile can be reused by a different protocol.
1) Map -- For each character in the input, check if it has a mapping and, if so, replace it with its mapping. This is described in section 3.
2) Normalize -- Possibly normalize the result of step 1 using Unicode normalization. This is described in section 4.
3) Prohibit -- Check for any characters that are not allowed in the output. If any are found, return an error. This is described in section 5.
4) Check bidi -- Possibly check for right-to-left characters, and if any are found, make sure that the whole string satisfies the requirements for bidirectional strings. If the string does not satisfy the requirements for bidirectional strings, return an error. This is described in section 6.
The above steps MUST be performed in the order given to comply with this specification.
The mappings described in section 3, and the optional Unicode normalization described in section 4, can be one-to-none, one-to-one, one-to-many, many-to-one, or many-to-many. That is, some characters might be eliminated or replaced by more than one character, and the output of this step might be shorter or longer than the input. Because of this, the system using stringprep MUST be prepared to receive a longer or shorter string than the one input in the stringprep algorithm.
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Each character in the input stream MUST be checked against a mapping table. The mapping table SHOULD come from this document, although the mapping table MAY be added to or altered by the profile. The mapping tables are subsections of appendix B.
The lists in appendix BMUST be used by implementations of this specification. If there are any discrepancies between the lists in appendix B and subsections below, the lists in appendix B always takes precedence.
For any individual character, the mapping table MAY specify that a character be mapped to nothing, or mapped to one other character, or mapped to a string of other characters.
Mapped characters are not re-scanned during the mapping step. That is, if character A at position X is mapped to character B, character B which is now at position X is not checked against the mapping table.
The following characters are simply deleted from the input (that is, they are mapped to nothing) because their presence or absence in protocol identifiers should not make two strings different. They are listed in Table B.1.
Some characters are only useful in line-based text, and are otherwise invisible and ignored.
00AD; SOFT HYPHEN 1806; MONGOLIAN TODO SOFT HYPHEN 200B; ZERO WIDTH SPACE 2060; WORD JOINER FEFF; ZERO WIDTH NO-BREAK SPACE
Some characters affect glyph choice and glyph placement, but do not bear semantics.
034F; COMBINING GRAPHEME JOINER 180B; MONGOLIAN FREE VARIATION SELECTOR ONE 180C; MONGOLIAN FREE VARIATION SELECTOR TWO 180D; MONGOLIAN FREE VARIATION SELECTOR THREE 200C; ZERO WIDTH NON-JOINER 200D; ZERO WIDTH JOINER FE00; VARIATION SELECTOR-1 FE01; VARIATION SELECTOR-2
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If a profile is going to map characters for case-insensitive comparison, that profile SHOULD map using either appendix B.2 or appendix B.3. appendix B.2 is for profiles that also use Unicode normalization form KC, while appendix B.3 is for profiles that do not use Unicode normalization. These tables map from uppercase to lowercase characters. Note that this could have been "change all lowercase characters into uppercase characters". However, the upper-to-lower folding was chosen because there is a tradition of using lowercase in current Internet applications and protocols.
If a profile creates its own mapping tables for case folding, they SHOULD be based on [UTR21], and SHOULD map from uppercase characters to lowercase. The "CaseFolding.txt" file from the Unicode database SHOULD be used to prepare the mapping table. The profile SHOULD do full case mapping (that is, using statuses C, F, and I).
If the profile is using Unicode normalization form KC (as described in section 4 of this document), it is important to note that there are some characters that do not have mappings in [UTR21] but still need processing. These characters include a few Greek characters and many symbols that contain Latin characters. The list of characters to add to the mapping table can determined by the following algorithm:
b = NormalizeWithKC(Fold(a)); c = NormalizeWithKC(Fold(b)); if c is not the same as b, add a mapping for "a to c".
Because NormalizeWithKC(Fold(c)) always equals c, the table is stable from that point on.
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Appendix B.3 is derived from the CaseFolding-3.txt file associated with Unicode 3.2; appendix B.2 is based on appendix B.3 with the additional characters added from the algorithm above.
Authors of profiles of this document need to consider the effects of changing the mapping of any currently-assigned character when updating their profiles. Adding a new mapping for a currently- assigned character, or changing an existing mapping, could cause a variance between the behavior of systems that have been updated and systems that have not been updated.
The output of the mapping step is optionally normalized using one of the Unicode normalization forms, as described in [UAX15]. A profile can specify one of two options for Unicode normalization:
- no normalization
- Unicode normalization with form KC
A profile MAY choose to do no normalization. However, such a profile can easily yield results that will be surprising to typical users, depending on the input mechanism they use. For example, some input mechanisms enter compatibility characters that look exactly like the underlying characters, but have different code points. Another example of where Unicode normalization helps create predictable results is with characters that have multiple combining diacritics: normalization orders those diacritics in a predictable fashion.
On the other hand, Unicode normalization requires fairly large tables and somewhat complicated character reordering logic. The size and complexity should not be considered daunting except in the most restricted of environments, and needs to be weighed against the problems of user surprise from comparing unnormalized strings. Note that the tables used for normalization are not given in this document, but instead must be derived from the Unicode database, as described in [UAX15].
There is a third form of normalization, Unicode normalization with form C. If a profile is going to use a Unicode normalization, it MUST use Unicode normalization form KC. Form KC maps many "compatibility characters" to their equivalents. Some user interface systems make it possible to enter compatibility characters instead of the base equivalents. Thus, using form KC instead of form C will cause more strings that users would expect to match to actually match.
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A profile that specifies Unicode normalization MUST use the normalization in [UAX15] that is associated with the version of the Unicode character set specified for the profile.
The composition process described in [UAX15] requires a fixed composition version of Unicode to ensure that strings normalized under one version of Unicode remain normalized under all future versions of Unicode.
The IETF is relying on Unicode not to change the normalization of currently-assigned characters in future versions of normalization. If a future version of the normalization tables changes the normalized value of an existing character, authors of profiles of this document have to look at the changes very carefully before they update their normalization tables. Such a change could cause a variance between the behavior of systems that have been updated and systems that have not been updated.
Before the text can be emitted, it MUST be checked for prohibited code points. There are a variety of prohibited code points, as described in this section. A profile of this document MAY use all or some of the tables in appendix C.
The stringprep process never emits both an error and a string. If an error is detected during the checking for prohibited code points, only an error is returned.
Note that the subsections below describe how the tables in appendix C were formed. They are here for people who want to understand more, but they should be ignored by implementors. Implementations that use tables MUST map based on the tables themselves, not based on the descriptions in this section of how the tables were created.
The lists in appendix CMUST be used by implementations of this specification. If there are any discrepancies between the lists in appendix C and subsections below, the lists in appendix C always take precedence.
Some code points listed in one section may also appear in other sections.
It is important to note that a profile of this document MAY prohibit additional characters.
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Each subsection of this section has a matching subsection in appendix C. For example, the characters listed in section 5.1 are listed in appendix C.1.
Space characters can make accurate visual transcription of strings nearly impossible and could lead to user entry errors in many ways. Note that the list below is split into two tables in appendix C: Table C.1.1 contains the ASCII code points, while Table C.1.2 contains the non-ASCII code points. Most profiles of this document that want to prohibit space characters will want to include both tables.
0020; SPACE 00A0; NO-BREAK SPACE 1680; OGHAM SPACE MARK 2000; EN QUAD 2001; EM QUAD 2002; EN SPACE 2003; EM SPACE 2004; THREE-PER-EM SPACE 2005; FOUR-PER-EM SPACE 2006; SIX-PER-EM SPACE 2007; FIGURE SPACE 2008; PUNCTUATION SPACE 2009; THIN SPACE 200A; HAIR SPACE 200B; ZERO WIDTH SPACE 202F; NARROW NO-BREAK SPACE 205F; MEDIUM MATHEMATICAL SPACE 3000; IDEOGRAPHIC SPACE
Control characters (or characters with control function) cannot be seen and can cause unpredictable results when displayed. Note that the list below is split into two tables in appendix C: Table C.2.1 contains the ASCII code points, while Table C.2.2 contains the non- ASCII code points. Most profiles of this document that want to prohibit control characters will want to include both tables.
0000-001F; [CONTROL CHARACTERS] 007F; DELETE 0080-009F; [CONTROL CHARACTERS] 06DD; ARABIC END OF AYAH 070F; SYRIAC ABBREVIATION MARK 180E; MONGOLIAN VOWEL SEPARATOR
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200C; ZERO WIDTH NON-JOINER 200D; ZERO WIDTH JOINER 2028; LINE SEPARATOR 2029; PARAGRAPH SEPARATOR 2060; WORD JOINER 2061; FUNCTION APPLICATION 2062; INVISIBLE TIMES 2063; INVISIBLE SEPARATOR 206A-206F; [CONTROL CHARACTERS] FEFF; ZERO WIDTH NO-BREAK SPACE FFF9-FFFC; [CONTROL CHARACTERS] 1D173-1D17A; [MUSICAL CONTROL CHARACTERS]
Non-character code points are code points that have been allocated in ISO/IEC 10646 but are not characters. Because they are already assigned, they are guaranteed not to later change into characters.
The following code points are permanently reserved for use as surrogate code values in the UTF-16 encoding, will never be assigned to characters in the Unicode repertoire, and are therefore prohibited:
Although the replacement character (U+FFFD) might be used when a string is displayed, it doesn't make sense for it to be part of the string itself. It is often displayed by renderers to indicate "there would be some character here, but it cannot be rendered". For example, on a computer with no Asian fonts, a string with three ideographs might be rendered with three replacement characters.
The ideographic description characters allow different sequences of characters to be rendered the same way, which makes them inappropriate for strings that have to have a single canonical representation.
Most characters are displayed from left to right, but some are displayed from right to left. This feature of Unicode is called "bidirectional text", or "bidi" for short. The Unicode standard has an extensive discussion of how to reorder glyphs for display when dealing with bidirectional text such as Arabic or Hebrew. See [UAX9] for more information. In particular, all Unicode text is stored in logical order.
A profile MAY choose to ignore bidirectional text. However, ignoring bidirectional text can cause display ambiguities. For example, it is quite easy to create two different strings with the same characters (but in different order) that are correctly displayed identically. Therefore, in order to avoid most problems with ambiguous bidirectional text display, profile creators should strongly consider including the bidirectional character handling described in this section in their profile.
The stringprep process never emits both an error and a string. If an error is detected during the checking of bidirectional strings, only an error is returned.
[Unicode3.2] defines several bidirectional categories; each character has one bidirectional category assigned to it. For the purposes of the requirements below, an "RandALCat character" is a character that has Unicode bidirectional categories "R" or "AL"; an "LCat character" is a character that has Unicode bidirectional category "L". Note
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that there are many characters which fall in neither of the above definitions; Latin digits (<U+0030> through <U+0039>) are examples of this because they have bidirectional category "EN".
In any profile that specifies bidirectional character handling, all three of the following requirements MUST be met:
1) The characters in section 5.8MUST be prohibited.
2) If a string contains any RandALCat character, the string MUST NOT contain any LCat character.
3) If a string contains any RandALCat character, a RandALCat character MUST be the first character of the string, and a RandALCat character MUST be the last character of the string.
Note that requirement 3 prohibits strings such as <U+0627><U+0031> ("aleph 1") but allows strings such as <U+0627><U+0031><U+0628> ("aleph 1 beh"). [UAX9] goes into great detail about the display order of strings that contain particular categories of characters in particular sequences.
Table D.1 lists the characters that belong to Unicode bidirectional categories "R" and "AL". Table D.2 lists all the characters that belong to Unicode bidirectonal category "L". These tables are derived from [Unicode3.2].
This section describes two different types of strings in typical protocols where internationalized strings are used: "stored strings" and "queries". Of course, different Internet protocols use strings very differently, so these terms cannot be used exactly in every protocol that needs to use stringprep. In general, "stored strings" are strings that are used in protocol identifiers and named entities, such as names in digital certificates and DNS domain name parts. "Queries" are strings that are used to match against strings that are stored identifiers, such as user-entered names for digital certificate authorities and DNS lookups.
All code points not assigned in the character repertoire named in a stringprep profile are called "unassigned code points". Stored strings using the profile MUST NOT contain any unassigned code points. Queries for matching strings MAY contain unassigned code points. Note that this is the only part of this document where the requirements for queries differs from the requirements for stored strings.
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Using two different policies for where unassigned code points can appear removes the need for versioning in protocols that use stringprep profiles. This is very useful since it makes the overall processing simpler and does not impose a "protocol" to handle versioning. It is expected that the ISO/IEC 10646 and Unicode repertoires will be updated fairly frequently; at the time that this document is being written, it has happened approximately once a year. Each time a new version of a repertoire appears, a new version of a profile MAY be created. Some end users will want to use the new code points as soon as they are defined.
The list of unassigned code points MUST be given in a profile, and that list MUST be used by implementations of the profile.
The goal of the requirements in this section is to prevent comparisons between two strings that were both permitted to contain unassigned code points. When two strings X and Y are compared and string Y was prepared in a way that permits unassigned code points, a negative result to the comparison is not definitive; it's possible that the strings don't match even though they would match if a more recent version of the profile were used for Y. However, if both X and Y were prepared in a way that permits unassigned code points, something worse can happen: even a positive result for the comparison is not definitive. It is possible that the strings do match even though they would not match if a more recent version of the profile were used (one that prohibits a code point appearing in both X and Y).
Due to the way that versioning is handled in this section, stored strings that are embedded in structures that cannot be changed (such as the signed parts of digital certificates) MUST NOT contain any unassigned code points.
Each code point in a repertoire named by a profile of stringprep can be categorized by how it acts in the process described in earlier sections of this document:
AO Code points that can be in the output
MN Code points that cannot be in the output because they never appear as output from mapping or normalization
D Code points that cannot be in the output because they are disallowed in the prohibition step
U Unassigned code points
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A subsequent version of a profile that references a newer version of a repertoire with new code points will inherently have some code points move from category U to either D, MN, or AO. For backwards compatibility, a subsequent version of a profile MUST NOT move code points from any other category. That is, current AO, MN, or D code points MUST NOT ever change to a different category.
Stored strings MUST NOT contain any code points outside of AO for the latest version of a profile. That is, they are forbidden to contain code points from the MN, D, or U categories.
Applications creating queries MUST treat U code points as if they were AO when preparing the query to be entered in the process described by a profile of stringprep. Those applications MAY optionally have a preprocessor that provide stricter checks: treating unassigned code points in the input as errors, or warning the user about the fact that the code point is unassigned in the version of a profile that the software is based on; such a choice is a local matter for the software.
7.2 Reasons for the difference between stored strings and queries
Different software using different versions of a stringprep profile need to interoperate with maximal compatibility. The scheme described in this section (stored strings MUST NOT contain unassigned code points, queries MAY include unassigned code points) allows that compatibility without introducing any known security or interoperability issues.
The list below shows what happens if a query contains a code point from category U that is allowed in a newer version of a profile. The query either matches the string that was intended, or matches no string at all. In this list, the query comes from an application using version "oldVersion" of a profile, the stored string was created using version "newVersion" of the same profile, and the code point X was in category U in oldVersion, and has changed category to AO, MN, or D. There are 3 possible scenarios:
1. X is assigned to AO -- In newVersion, X is in category AO. Because the application passed X through, it gets back a positive match with the stored string. There is one exceptional case, where X is a combining mark.
The order of combining marks is normalized, so if another combining mark Y has a lower combining class than X then XY will be put in the canonical order YX. (Unassigned code points are never reordered, so this doesn't happen in oldVersion). If the query contains YX, the query will get positive match with the
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stored string. However, no string can be stored with XY, so a query with XY will get a negative answer to the test for matching.
2. X is assigned to MN -- In newVersion, X is normalized to code point "nX" and therefore X is now put in category MN. This cannot exist in any stored string, so any query containing X will get a negative answer to the test for matching. Note, however, if the query had contained the letter nX, it would have positively matched.
3. X is assigned to D -- In newVersion, X is in category D. This cannot exist in any stored string, so any query containing X will get a negative answer to the test for matching.
In none of the cases does the query get data for a stored string other than the one it actually tried to match against.
Profiles are stable between versions in the following sense: If a string S has been prepared using newVersion, then it will not change if it is subsequently prepared using oldVersion.
Another way to see that this versioning system works is to compare what happens when an application uses a newer or older version of a profile.
Newer query application -- Suppose that a querying application is using version newVersion and the stored string was created using version oldVersion. This case is simple: there will be no characters in the stored string that cannot be queried by the application because the new profile uses a superset of the code points used for making the stored string.
Newer stored string -- Suppose that a querying application is using oldVersion and the stored string was created using a profile that uses newVersion. Because the querying application let unassigned code points pass through, the user can query on stored strings that use code points in newVersion. No stored strings can have code points that are unassigned in newVersion, since that is illegal. In order to get a match, the querying application has to enter the unassigned code points in the proper order, and has to use unassigned code points that would make it through both the mapping and the normalization steps.
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[Unicode3.2] The Unicode Consortium. The Unicode Standard, Version 3.2.0 is defined by The Unicode Standard, Version 3.0 (Reading, MA, Addison-Wesley, 2000. ISBN 0-201-61633-5), as amended by the Unicode Standard Annex #27: Unicode 3.1 (http://www.unicode.org/reports/tr27/) and by the Unicode Standard Annex #28: Unicode 3.2 (http://www.unicode.org/reports/tr28/).
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997.
[ISO10646] ISO/IEC, "Information Technology - Universal Multiple- Octet Coded Character Set (UCS) - Part 1: Architecture and Basic Multilingual Plane", ISO/IEC 10646-1:2000, October 2000.
[RFC2434] Narten, T. and H. Alvestrand, "Guidelines for IANA Considerations", BCP 26, RFC 2434, October 1998.
Stringprep is used with Unicode characters. There are security considerations that are specific to stringprep, and others that are generic to using Unicode.
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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. User applications can help disambiguate some similar-looking characters by showing the user when a string changes between scripts.
Most profiles of stringprep can cause changes in strings that are input to stringprep. Because of this, protocols that have sets of non-allowed characters or sequences MUST check for the non-allowed characters or sequences after the stringprep processing.
This document does not mandate the checking of bidirectional characters in section 6. If the requirements in section 6 are not used in a profile of stringprep, it is easy to create many strings whose characters are in different order but are displayed identically. This can cause security-related user confusion similar to look-alike characters, as described above.
Stringprep does not do anything to assure that any algorithms translating characters from non-Unicode into Unicode produce the same output in all implementations.
Some Unicode codepoints are invisible. Protocols that allow these characters (that is, do not map them out or prohibit them in stringprep) can cause users confusion when two identical-looking strings do not match.
Using Unicode characters explicitly forces applications to use multi-octet characters. Converting an application from one that uses single-octet characters to one that uses multi-octet characters must be done very carefully, particularly in an application that checks for values of characters or sorts characters.
Protocols that use stringprep usually also use encodings of Unicode, such as UTF-8 or UTF-16. Some applications using those encodings have been known to not check for illegal or ill-formed sequences in the encodings, and thereby have not detected sequences of octets that would have been detected if they used just ASCII. For example, in
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RFC 3454 Preparation of Internationalized Strings December 2002
UTF-8 the octet sequence "0xC0 0xAB" is an illegal formation of U+002B (plus sign). All programs should reject any string that is an illegal or ill-formed octet sequence for the encoding being used.
Both Unicode normalization and conversion between Unicode encodings can cause strings to grow or shrink. Programs that used fixed-size buffers, or that make assumptions that buffers will always be greater than or less than particular sizes, are likely to fail in insecure fashions when using Unicode normalization or encoding conversions.
Covering an extensive list of security threats and considerations on the use of current and future versions of Unicode is outside of the scope of this document.
Stringprep profiles MUST have IETF consensus as described in [RFC2434]. Each profile MUST be reviewed by the IESG before it is registered. The IESG MAY change a profile before registration.
IANA has set up a registry of stringprep profiles. This registry is a single text file that lists the known profiles. Each entry in the registry has three fields:
- Profile name
- RFC in which the profile is defined
- Indicator whether or not this is the newest version of the profile
Each version of a profile will remain listed in the registry forever. That is, if a new version of a profile supersedes an earlier version, both versions will continue to be listed in the registry, but the current version indicator will be turned off for the earlier version and turned on for the newer version.
It is probably harmful if a large number of profiles of stringprep proliferate. Therefore, the IESG may reject proposals for new profiles and instead suggest that protocols reuse existing profiles.
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RFC 3454 Preparation of Internationalized Strings December 2002
Many people from the IETF IDN Working Group and the Unicode Technical Committee contributed ideas that went into the first document of this document. Mark Davis and Patrik Faltstrom were particularly helpful in some of the ideas, such as the versioning description.
The IDN nameprep design team made many useful changes to the first 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
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RFC 3454 Preparation of Internationalized Strings December 2002
The following is the mapping table from section 3. The table has three columns:
- the code point that is mapped from - the zero or more code points that it is mapped to - the reason for the mapping
The columns are separated by semicolons. Note that the second column may be empty, or it may have one code point, or it may have more than one code point, with each code point separated by a space.
----- Start Table B.1 ----- 00AD; ; Map to nothing 034F; ; Map to nothing 1806; ; Map to nothing 180B; ; Map to nothing 180C; ; Map to nothing 180D; ; Map to nothing 200B; ; Map to nothing 200C; ; Map to nothing 200D; ; Map to nothing
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RFC 3454 Preparation of Internationalized Strings December 2002
2060; ; Map to nothing FE00; ; Map to nothing FE01; ; Map to nothing FE02; ; Map to nothing FE03; ; Map to nothing FE04; ; Map to nothing FE05; ; Map to nothing FE06; ; Map to nothing FE07; ; Map to nothing FE08; ; Map to nothing FE09; ; Map to nothing FE0A; ; Map to nothing FE0B; ; Map to nothing FE0C; ; Map to nothing FE0D; ; Map to nothing FE0E; ; Map to nothing FE0F; ; Map to nothing FEFF; ; Map to nothing ----- End Table B.1 -----
----- Start Table B.2 ----- 0041; 0061; Case map 0042; 0062; Case map 0043; 0063; Case map 0044; 0064; Case map 0045; 0065; Case map 0046; 0066; Case map 0047; 0067; Case map 0048; 0068; Case map 0049; 0069; Case map 004A; 006A; Case map 004B; 006B; Case map 004C; 006C; Case map 004D; 006D; Case map 004E; 006E; Case map 004F; 006F; Case map 0050; 0070; Case map 0051; 0071; Case map 0052; 0072; Case map 0053; 0073; Case map 0054; 0074; Case map 0055; 0075; Case map 0056; 0076; Case map 0057; 0077; Case map 0058; 0078; Case map 0059; 0079; Case map
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RFC 3454 Preparation of Internationalized Strings December 2002
005A; 007A; Case map 00B5; 03BC; Case map 00C0; 00E0; Case map 00C1; 00E1; Case map 00C2; 00E2; Case map 00C3; 00E3; Case map 00C4; 00E4; Case map 00C5; 00E5; Case map 00C6; 00E6; Case map 00C7; 00E7; Case map 00C8; 00E8; Case map 00C9; 00E9; Case map 00CA; 00EA; Case map 00CB; 00EB; Case map 00CC; 00EC; Case map 00CD; 00ED; Case map 00CE; 00EE; Case map 00CF; 00EF; Case map 00D0; 00F0; Case map 00D1; 00F1; Case map 00D2; 00F2; Case map 00D3; 00F3; Case map 00D4; 00F4; Case map 00D5; 00F5; Case map 00D6; 00F6; Case map 00D8; 00F8; Case map 00D9; 00F9; Case map 00DA; 00FA; Case map 00DB; 00FB; Case map 00DC; 00FC; Case map 00DD; 00FD; Case map 00DE; 00FE; Case map 00DF; 0073 0073; Case map 0100; 0101; Case map 0102; 0103; Case map 0104; 0105; Case map 0106; 0107; Case map 0108; 0109; Case map 010A; 010B; Case map 010C; 010D; Case map 010E; 010F; Case map 0110; 0111; Case map 0112; 0113; Case map 0114; 0115; Case map 0116; 0117; Case map 0118; 0119; Case map 011A; 011B; Case map 011C; 011D; Case map
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RFC 3454 Preparation of Internationalized Strings December 2002
011E; 011F; Case map 0120; 0121; Case map 0122; 0123; Case map 0124; 0125; Case map 0126; 0127; Case map 0128; 0129; Case map 012A; 012B; Case map 012C; 012D; Case map 012E; 012F; Case map 0130; 0069 0307; Case map 0132; 0133; Case map 0134; 0135; Case map 0136; 0137; Case map 0139; 013A; Case map 013B; 013C; Case map 013D; 013E; Case map 013F; 0140; Case map 0141; 0142; Case map 0143; 0144; Case map 0145; 0146; Case map 0147; 0148; Case map 0149; 02BC 006E; Case map 014A; 014B; Case map 014C; 014D; Case map 014E; 014F; Case map 0150; 0151; Case map 0152; 0153; Case map 0154; 0155; Case map 0156; 0157; Case map 0158; 0159; Case map 015A; 015B; Case map 015C; 015D; Case map 015E; 015F; Case map 0160; 0161; Case map 0162; 0163; Case map 0164; 0165; Case map 0166; 0167; Case map 0168; 0169; Case map 016A; 016B; Case map 016C; 016D; Case map 016E; 016F; Case map 0170; 0171; Case map 0172; 0173; Case map 0174; 0175; Case map 0176; 0177; Case map 0178; 00FF; Case map 0179; 017A; Case map 017B; 017C; Case map
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RFC 3454 Preparation of Internationalized Strings December 2002
017D; 017E; Case map 017F; 0073; Case map 0181; 0253; Case map 0182; 0183; Case map 0184; 0185; Case map 0186; 0254; Case map 0187; 0188; Case map 0189; 0256; Case map 018A; 0257; Case map 018B; 018C; Case map 018E; 01DD; Case map 018F; 0259; Case map 0190; 025B; Case map 0191; 0192; Case map 0193; 0260; Case map 0194; 0263; Case map 0196; 0269; Case map 0197; 0268; Case map 0198; 0199; Case map 019C; 026F; Case map 019D; 0272; Case map 019F; 0275; Case map 01A0; 01A1; Case map 01A2; 01A3; Case map 01A4; 01A5; Case map 01A6; 0280; Case map 01A7; 01A8; Case map 01A9; 0283; Case map 01AC; 01AD; Case map 01AE; 0288; Case map 01AF; 01B0; Case map 01B1; 028A; Case map 01B2; 028B; Case map 01B3; 01B4; Case map 01B5; 01B6; Case map 01B7; 0292; Case map 01B8; 01B9; Case map 01BC; 01BD; Case map 01C4; 01C6; Case map 01C5; 01C6; Case map 01C7; 01C9; Case map 01C8; 01C9; Case map 01CA; 01CC; Case map 01CB; 01CC; Case map 01CD; 01CE; Case map 01CF; 01D0; Case map 01D1; 01D2; Case map 01D3; 01D4; Case map
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RFC 3454 Preparation of Internationalized Strings December 2002
01D5; 01D6; Case map 01D7; 01D8; Case map 01D9; 01DA; Case map 01DB; 01DC; Case map 01DE; 01DF; Case map 01E0; 01E1; Case map 01E2; 01E3; Case map 01E4; 01E5; Case map 01E6; 01E7; Case map 01E8; 01E9; Case map 01EA; 01EB; Case map 01EC; 01ED; Case map 01EE; 01EF; Case map 01F0; 006A 030C; Case map 01F1; 01F3; Case map 01F2; 01F3; Case map 01F4; 01F5; Case map 01F6; 0195; Case map 01F7; 01BF; Case map 01F8; 01F9; Case map 01FA; 01FB; Case map 01FC; 01FD; Case map 01FE; 01FF; Case map 0200; 0201; Case map 0202; 0203; Case map 0204; 0205; Case map 0206; 0207; Case map 0208; 0209; Case map 020A; 020B; Case map 020C; 020D; Case map 020E; 020F; Case map 0210; 0211; Case map 0212; 0213; Case map 0214; 0215; Case map 0216; 0217; Case map 0218; 0219; Case map 021A; 021B; Case map 021C; 021D; Case map 021E; 021F; Case map 0220; 019E; Case map 0222; 0223; Case map 0224; 0225; Case map 0226; 0227; Case map 0228; 0229; Case map 022A; 022B; Case map 022C; 022D; Case map 022E; 022F; Case map 0230; 0231; Case map
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RFC 3454 Preparation of Internationalized Strings December 2002
0232; 0233; Case map 0345; 03B9; Case map 037A; 0020 03B9; Additional folding 0386; 03AC; Case map 0388; 03AD; Case map 0389; 03AE; Case map 038A; 03AF; Case map 038C; 03CC; Case map 038E; 03CD; Case map 038F; 03CE; Case map 0390; 03B9 0308 0301; Case map 0391; 03B1; Case map 0392; 03B2; Case map 0393; 03B3; Case map 0394; 03B4; Case map 0395; 03B5; Case map 0396; 03B6; Case map 0397; 03B7; Case map 0398; 03B8; Case map 0399; 03B9; Case map 039A; 03BA; Case map 039B; 03BB; Case map 039C; 03BC; Case map 039D; 03BD; Case map 039E; 03BE; Case map 039F; 03BF; Case map 03A0; 03C0; Case map 03A1; 03C1; Case map 03A3; 03C3; Case map 03A4; 03C4; Case map 03A5; 03C5; Case map 03A6; 03C6; Case map 03A7; 03C7; Case map 03A8; 03C8; Case map 03A9; 03C9; Case map 03AA; 03CA; Case map 03AB; 03CB; Case map 03B0; 03C5 0308 0301; Case map 03C2; 03C3; Case map 03D0; 03B2; Case map 03D1; 03B8; Case map 03D2; 03C5; Additional folding 03D3; 03CD; Additional folding 03D4; 03CB; Additional folding 03D5; 03C6; Case map 03D6; 03C0; Case map 03D8; 03D9; Case map 03DA; 03DB; Case map
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RFC 3454 Preparation of Internationalized Strings December 2002
03DC; 03DD; Case map 03DE; 03DF; Case map 03E0; 03E1; Case map 03E2; 03E3; Case map 03E4; 03E5; Case map 03E6; 03E7; Case map 03E8; 03E9; Case map 03EA; 03EB; Case map 03EC; 03ED; Case map 03EE; 03EF; Case map 03F0; 03BA; Case map 03F1; 03C1; Case map 03F2; 03C3; Case map 03F4; 03B8; Case map 03F5; 03B5; Case map 0400; 0450; Case map 0401; 0451; Case map 0402; 0452; Case map 0403; 0453; Case map 0404; 0454; Case map 0405; 0455; Case map 0406; 0456; Case map 0407; 0457; Case map 0408; 0458; Case map 0409; 0459; Case map 040A; 045A; Case map 040B; 045B; Case map 040C; 045C; Case map 040D; 045D; Case map 040E; 045E; Case map 040F; 045F; Case map 0410; 0430; Case map 0411; 0431; Case map 0412; 0432; Case map 0413; 0433; Case map 0414; 0434; Case map 0415; 0435; Case map 0416; 0436; Case map 0417; 0437; Case map 0418; 0438; Case map 0419; 0439; Case map 041A; 043A; Case map 041B; 043B; Case map 041C; 043C; Case map 041D; 043D; Case map 041E; 043E; Case map 041F; 043F; Case map 0420; 0440; Case map
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RFC 3454 Preparation of Internationalized Strings December 2002
0421; 0441; Case map 0422; 0442; Case map 0423; 0443; Case map 0424; 0444; Case map 0425; 0445; Case map 0426; 0446; Case map 0427; 0447; Case map 0428; 0448; Case map 0429; 0449; Case map 042A; 044A; Case map 042B; 044B; Case map 042C; 044C; Case map 042D; 044D; Case map 042E; 044E; Case map 042F; 044F; Case map 0460; 0461; Case map 0462; 0463; Case map 0464; 0465; Case map 0466; 0467; Case map 0468; 0469; Case map 046A; 046B; Case map 046C; 046D; Case map 046E; 046F; Case map 0470; 0471; Case map 0472; 0473; Case map 0474; 0475; Case map 0476; 0477; Case map 0478; 0479; Case map 047A; 047B; Case map 047C; 047D; Case map 047E; 047F; Case map 0480; 0481; Case map 048A; 048B; Case map 048C; 048D; Case map 048E; 048F; Case map 0490; 0491; Case map 0492; 0493; Case map 0494; 0495; Case map 0496; 0497; Case map 0498; 0499; Case map 049A; 049B; Case map 049C; 049D; Case map 049E; 049F; Case map 04A0; 04A1; Case map 04A2; 04A3; Case map 04A4; 04A5; Case map 04A6; 04A7; Case map 04A8; 04A9; Case map
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RFC 3454 Preparation of Internationalized Strings December 2002
04AA; 04AB; Case map 04AC; 04AD; Case map 04AE; 04AF; Case map 04B0; 04B1; Case map 04B2; 04B3; Case map 04B4; 04B5; Case map 04B6; 04B7; Case map 04B8; 04B9; Case map 04BA; 04BB; Case map 04BC; 04BD; Case map 04BE; 04BF; Case map 04C1; 04C2; Case map 04C3; 04C4; Case map 04C5; 04C6; Case map 04C7; 04C8; Case map 04C9; 04CA; Case map 04CB; 04CC; Case map 04CD; 04CE; Case map 04D0; 04D1; Case map 04D2; 04D3; Case map 04D4; 04D5; Case map 04D6; 04D7; Case map 04D8; 04D9; Case map 04DA; 04DB; Case map 04DC; 04DD; Case map 04DE; 04DF; Case map 04E0; 04E1; Case map 04E2; 04E3; Case map 04E4; 04E5; Case map 04E6; 04E7; Case map 04E8; 04E9; Case map 04EA; 04EB; Case map 04EC; 04ED; Case map 04EE; 04EF; Case map 04F0; 04F1; Case map 04F2; 04F3; Case map 04F4; 04F5; Case map 04F8; 04F9; Case map 0500; 0501; Case map 0502; 0503; Case map 0504; 0505; Case map 0506; 0507; Case map 0508; 0509; Case map 050A; 050B; Case map 050C; 050D; Case map 050E; 050F; Case map 0531; 0561; Case map 0532; 0562; Case map
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RFC 3454 Preparation of Internationalized Strings December 2002
0533; 0563; Case map 0534; 0564; Case map 0535; 0565; Case map 0536; 0566; Case map 0537; 0567; Case map 0538; 0568; Case map 0539; 0569; Case map 053A; 056A; Case map 053B; 056B; Case map 053C; 056C; Case map 053D; 056D; Case map 053E; 056E; Case map 053F; 056F; Case map 0540; 0570; Case map 0541; 0571; Case map 0542; 0572; Case map 0543; 0573; Case map 0544; 0574; Case map 0545; 0575; Case map 0546; 0576; Case map 0547; 0577; Case map 0548; 0578; Case map 0549; 0579; Case map 054A; 057A; Case map 054B; 057B; Case map 054C; 057C; Case map 054D; 057D; Case map 054E; 057E; Case map 054F; 057F; Case map 0550; 0580; Case map 0551; 0581; Case map 0552; 0582; Case map 0553; 0583; Case map 0554; 0584; Case map 0555; 0585; Case map 0556; 0586; Case map 0587; 0565 0582; Case map 1E00; 1E01; Case map 1E02; 1E03; Case map 1E04; 1E05; Case map 1E06; 1E07; Case map 1E08; 1E09; Case map 1E0A; 1E0B; Case map 1E0C; 1E0D; Case map 1E0E; 1E0F; Case map 1E10; 1E11; Case map 1E12; 1E13; Case map 1E14; 1E15; Case map
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RFC 3454 Preparation of Internationalized Strings December 2002
1E16; 1E17; Case map 1E18; 1E19; Case map 1E1A; 1E1B; Case map 1E1C; 1E1D; Case map 1E1E; 1E1F; Case map 1E20; 1E21; Case map 1E22; 1E23; Case map 1E24; 1E25; Case map 1E26; 1E27; Case map 1E28; 1E29; Case map 1E2A; 1E2B; Case map 1E2C; 1E2D; Case map 1E2E; 1E2F; Case map 1E30; 1E31; Case map 1E32; 1E33; Case map 1E34; 1E35; Case map 1E36; 1E37; Case map 1E38; 1E39; Case map 1E3A; 1E3B; Case map 1E3C; 1E3D; Case map 1E3E; 1E3F; Case map 1E40; 1E41; Case map 1E42; 1E43; Case map 1E44; 1E45; Case map 1E46; 1E47; Case map 1E48; 1E49; Case map 1E4A; 1E4B; Case map 1E4C; 1E4D; Case map 1E4E; 1E4F; Case map 1E50; 1E51; Case map 1E52; 1E53; Case map 1E54; 1E55; Case map 1E56; 1E57; Case map 1E58; 1E59; Case map 1E5A; 1E5B; Case map 1E5C; 1E5D; Case map 1E5E; 1E5F; Case map 1E60; 1E61; Case map 1E62; 1E63; Case map 1E64; 1E65; Case map 1E66; 1E67; Case map 1E68; 1E69; Case map 1E6A; 1E6B; Case map 1E6C; 1E6D; Case map 1E6E; 1E6F; Case map 1E70; 1E71; Case map 1E72; 1E73; Case map 1E74; 1E75; Case map
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RFC 3454 Preparation of Internationalized Strings December 2002
1E76; 1E77; Case map 1E78; 1E79; Case map 1E7A; 1E7B; Case map 1E7C; 1E7D; Case map 1E7E; 1E7F; Case map 1E80; 1E81; Case map 1E82; 1E83; Case map 1E84; 1E85; Case map 1E86; 1E87; Case map 1E88; 1E89; Case map 1E8A; 1E8B; Case map 1E8C; 1E8D; Case map 1E8E; 1E8F; Case map 1E90; 1E91; Case map 1E92; 1E93; Case map 1E94; 1E95; Case map 1E96; 0068 0331; Case map 1E97; 0074 0308; Case map 1E98; 0077 030A; Case map 1E99; 0079 030A; Case map 1E9A; 0061 02BE; Case map 1E9B; 1E61; Case map 1EA0; 1EA1; Case map 1EA2; 1EA3; Case map 1EA4; 1EA5; Case map 1EA6; 1EA7; Case map 1EA8; 1EA9; Case map 1EAA; 1EAB; Case map 1EAC; 1EAD; Case map 1EAE; 1EAF; Case map 1EB0; 1EB1; Case map 1EB2; 1EB3; Case map 1EB4; 1EB5; Case map 1EB6; 1EB7; Case map 1EB8; 1EB9; Case map 1EBA; 1EBB; Case map 1EBC; 1EBD; Case map 1EBE; 1EBF; Case map 1EC0; 1EC1; Case map 1EC2; 1EC3; Case map 1EC4; 1EC5; Case map 1EC6; 1EC7; Case map 1EC8; 1EC9; Case map 1ECA; 1ECB; Case map 1ECC; 1ECD; Case map 1ECE; 1ECF; Case map 1ED0; 1ED1; Case map 1ED2; 1ED3; Case map
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RFC 3454 Preparation of Internationalized Strings December 2002
1ED4; 1ED5; Case map 1ED6; 1ED7; Case map 1ED8; 1ED9; Case map 1EDA; 1EDB; Case map 1EDC; 1EDD; Case map 1EDE; 1EDF; Case map 1EE0; 1EE1; Case map 1EE2; 1EE3; Case map 1EE4; 1EE5; Case map 1EE6; 1EE7; Case map 1EE8; 1EE9; Case map 1EEA; 1EEB; Case map 1EEC; 1EED; Case map 1EEE; 1EEF; Case map 1EF0; 1EF1; Case map 1EF2; 1EF3; Case map 1EF4; 1EF5; Case map 1EF6; 1EF7; Case map 1EF8; 1EF9; Case map 1F08; 1F00; Case map 1F09; 1F01; Case map 1F0A; 1F02; Case map 1F0B; 1F03; Case map 1F0C; 1F04; Case map 1F0D; 1F05; Case map 1F0E; 1F06; Case map 1F0F; 1F07; Case map 1F18; 1F10; Case map 1F19; 1F11; Case map 1F1A; 1F12; Case map 1F1B; 1F13; Case map 1F1C; 1F14; Case map 1F1D; 1F15; Case map 1F28; 1F20; Case map 1F29; 1F21; Case map 1F2A; 1F22; Case map 1F2B; 1F23; Case map 1F2C; 1F24; Case map 1F2D; 1F25; Case map 1F2E; 1F26; Case map 1F2F; 1F27; Case map 1F38; 1F30; Case map 1F39; 1F31; Case map 1F3A; 1F32; Case map 1F3B; 1F33; Case map 1F3C; 1F34; Case map 1F3D; 1F35; Case map 1F3E; 1F36; Case map
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RFC 3454 Preparation of Internationalized Strings December 2002
1F3F; 1F37; Case map 1F48; 1F40; Case map 1F49; 1F41; Case map 1F4A; 1F42; Case map 1F4B; 1F43; Case map 1F4C; 1F44; Case map 1F4D; 1F45; Case map 1F50; 03C5 0313; Case map 1F52; 03C5 0313 0300; Case map 1F54; 03C5 0313 0301; Case map 1F56; 03C5 0313 0342; Case map 1F59; 1F51; Case map 1F5B; 1F53; Case map 1F5D; 1F55; Case map 1F5F; 1F57; Case map 1F68; 1F60; Case map 1F69; 1F61; Case map 1F6A; 1F62; Case map 1F6B; 1F63; Case map 1F6C; 1F64; Case map 1F6D; 1F65; Case map 1F6E; 1F66; Case map 1F6F; 1F67; Case map 1F80; 1F00 03B9; Case map 1F81; 1F01 03B9; Case map 1F82; 1F02 03B9; Case map 1F83; 1F03 03B9; Case map 1F84; 1F04 03B9; Case map 1F85; 1F05 03B9; Case map 1F86; 1F06 03B9; Case map 1F87; 1F07 03B9; Case map 1F88; 1F00 03B9; Case map 1F89; 1F01 03B9; Case map 1F8A; 1F02 03B9; Case map 1F8B; 1F03 03B9; Case map 1F8C; 1F04 03B9; Case map 1F8D; 1F05 03B9; Case map 1F8E; 1F06 03B9; Case map 1F8F; 1F07 03B9; Case map 1F90; 1F20 03B9; Case map 1F91; 1F21 03B9; Case map 1F92; 1F22 03B9; Case map 1F93; 1F23 03B9; Case map 1F94; 1F24 03B9; Case map 1F95; 1F25 03B9; Case map 1F96; 1F26 03B9; Case map 1F97; 1F27 03B9; Case map 1F98; 1F20 03B9; Case map
Hoffman & Blanchet Standards Track [Page 45]
RFC 3454 Preparation of Internationalized Strings December 2002
1F99; 1F21 03B9; Case map 1F9A; 1F22 03B9; Case map 1F9B; 1F23 03B9; Case map 1F9C; 1F24 03B9; Case map 1F9D; 1F25 03B9; Case map 1F9E; 1F26 03B9; Case map 1F9F; 1F27 03B9; Case map 1FA0; 1F60 03B9; Case map 1FA1; 1F61 03B9; Case map 1FA2; 1F62 03B9; Case map 1FA3; 1F63 03B9; Case map 1FA4; 1F64 03B9; Case map 1FA5; 1F65 03B9; Case map 1FA6; 1F66 03B9; Case map 1FA7; 1F67 03B9; Case map 1FA8; 1F60 03B9; Case map 1FA9; 1F61 03B9; Case map 1FAA; 1F62 03B9; Case map 1FAB; 1F63 03B9; Case map 1FAC; 1F64 03B9; Case map 1FAD; 1F65 03B9; Case map 1FAE; 1F66 03B9; Case map 1FAF; 1F67 03B9; Case map 1FB2; 1F70 03B9; Case map 1FB3; 03B1 03B9; Case map 1FB4; 03AC 03B9; Case map 1FB6; 03B1 0342; Case map 1FB7; 03B1 0342 03B9; Case map 1FB8; 1FB0; Case map 1FB9; 1FB1; Case map 1FBA; 1F70; Case map 1FBB; 1F71; Case map 1FBC; 03B1 03B9; Case map 1FBE; 03B9; Case map 1FC2; 1F74 03B9; Case map 1FC3; 03B7 03B9; Case map 1FC4; 03AE 03B9; Case map 1FC6; 03B7 0342; Case map 1FC7; 03B7 0342 03B9; Case map 1FC8; 1F72; Case map 1FC9; 1F73; Case map 1FCA; 1F74; Case map 1FCB; 1F75; Case map 1FCC; 03B7 03B9; Case map 1FD2; 03B9 0308 0300; Case map 1FD3; 03B9 0308 0301; Case map 1FD6; 03B9 0342; Case map 1FD7; 03B9 0308 0342; Case map
Hoffman & Blanchet Standards Track [Page 46]
RFC 3454 Preparation of Internationalized Strings December 2002
1FD8; 1FD0; Case map 1FD9; 1FD1; Case map 1FDA; 1F76; Case map 1FDB; 1F77; Case map 1FE2; 03C5 0308 0300; Case map 1FE3; 03C5 0308 0301; Case map 1FE4; 03C1 0313; Case map 1FE6; 03C5 0342; Case map 1FE7; 03C5 0308 0342; Case map 1FE8; 1FE0; Case map 1FE9; 1FE1; Case map 1FEA; 1F7A; Case map 1FEB; 1F7B; Case map 1FEC; 1FE5; Case map 1FF2; 1F7C 03B9; Case map 1FF3; 03C9 03B9; Case map 1FF4; 03CE 03B9; Case map 1FF6; 03C9 0342; Case map 1FF7; 03C9 0342 03B9; Case map 1FF8; 1F78; Case map 1FF9; 1F79; Case map 1FFA; 1F7C; Case map 1FFB; 1F7D; Case map 1FFC; 03C9 03B9; Case map 20A8; 0072 0073; Additional folding 2102; 0063; Additional folding 2103; 00B0 0063; Additional folding 2107; 025B; Additional folding 2109; 00B0 0066; Additional folding 210B; 0068; Additional folding 210C; 0068; Additional folding 210D; 0068; Additional folding 2110; 0069; Additional folding 2111; 0069; Additional folding 2112; 006C; Additional folding 2115; 006E; Additional folding 2116; 006E 006F; Additional folding 2119; 0070; Additional folding 211A; 0071; Additional folding 211B; 0072; Additional folding 211C; 0072; Additional folding 211D; 0072; Additional folding 2120; 0073 006D; Additional folding 2121; 0074 0065 006C; Additional folding 2122; 0074 006D; Additional folding 2124; 007A; Additional folding 2126; 03C9; Case map 2128; 007A; Additional folding
Hoffman & Blanchet Standards Track [Page 47]
RFC 3454 Preparation of Internationalized Strings December 2002
212A; 006B; Case map 212B; 00E5; Case map 212C; 0062; Additional folding 212D; 0063; Additional folding 2130; 0065; Additional folding 2131; 0066; Additional folding 2133; 006D; Additional folding 213E; 03B3; Additional folding 213F; 03C0; Additional folding 2145; 0064; Additional folding 2160; 2170; Case map 2161; 2171; Case map 2162; 2172; Case map 2163; 2173; Case map 2164; 2174; Case map 2165; 2175; Case map 2166; 2176; Case map 2167; 2177; Case map 2168; 2178; Case map 2169; 2179; Case map 216A; 217A; Case map 216B; 217B; Case map 216C; 217C; Case map 216D; 217D; Case map 216E; 217E; Case map 216F; 217F; Case map 24B6; 24D0; Case map 24B7; 24D1; Case map 24B8; 24D2; Case map 24B9; 24D3; Case map 24BA; 24D4; Case map 24BB; 24D5; Case map 24BC; 24D6; Case map 24BD; 24D7; Case map 24BE; 24D8; Case map 24BF; 24D9; Case map 24C0; 24DA; Case map 24C1; 24DB; Case map 24C2; 24DC; Case map 24C3; 24DD; Case map 24C4; 24DE; Case map 24C5; 24DF; Case map 24C6; 24E0; Case map 24C7; 24E1; Case map 24C8; 24E2; Case map 24C9; 24E3; Case map 24CA; 24E4; Case map 24CB; 24E5; Case map
Hoffman & Blanchet Standards Track [Page 48]
RFC 3454 Preparation of Internationalized Strings December 2002
B.3 Mapping for case-folding used with no normalization
----- Start Table B.3 ----- 0041; 0061; Case map 0042; 0062; Case map 0043; 0063; Case map 0044; 0064; Case map 0045; 0065; Case map 0046; 0066; Case map 0047; 0067; Case map 0048; 0068; Case map 0049; 0069; Case map 004A; 006A; Case map 004B; 006B; Case map 004C; 006C; Case map 004D; 006D; Case map 004E; 006E; Case map 004F; 006F; Case map 0050; 0070; Case map 0051; 0071; Case map 0052; 0072; Case map 0053; 0073; Case map 0054; 0074; Case map 0055; 0075; Case map 0056; 0076; Case map 0057; 0077; Case map 0058; 0078; Case map 0059; 0079; Case map 005A; 007A; Case map 00B5; 03BC; Case map 00C0; 00E0; Case map 00C1; 00E1; Case map 00C2; 00E2; Case map 00C3; 00E3; Case map 00C4; 00E4; Case map 00C5; 00E5; Case map 00C6; 00E6; Case map 00C7; 00E7; Case map 00C8; 00E8; Case map 00C9; 00E9; Case map 00CA; 00EA; Case map 00CB; 00EB; Case map 00CC; 00EC; Case map 00CD; 00ED; Case map
Hoffman & Blanchet Standards Track [Page 61]
RFC 3454 Preparation of Internationalized Strings December 2002
00CE; 00EE; Case map 00CF; 00EF; Case map 00D0; 00F0; Case map 00D1; 00F1; Case map 00D2; 00F2; Case map 00D3; 00F3; Case map 00D4; 00F4; Case map 00D5; 00F5; Case map 00D6; 00F6; Case map 00D8; 00F8; Case map 00D9; 00F9; Case map 00DA; 00FA; Case map 00DB; 00FB; Case map 00DC; 00FC; Case map 00DD; 00FD; Case map 00DE; 00FE; Case map 00DF; 0073 0073; Case map 0100; 0101; Case map 0102; 0103; Case map 0104; 0105; Case map 0106; 0107; Case map 0108; 0109; Case map 010A; 010B; Case map 010C; 010D; Case map 010E; 010F; Case map 0110; 0111; Case map 0112; 0113; Case map 0114; 0115; Case map 0116; 0117; Case map 0118; 0119; Case map 011A; 011B; Case map 011C; 011D; Case map 011E; 011F; Case map 0120; 0121; Case map 0122; 0123; Case map 0124; 0125; Case map 0126; 0127; Case map 0128; 0129; Case map 012A; 012B; Case map 012C; 012D; Case map 012E; 012F; Case map 0130; 0069 0307; Case map 0132; 0133; Case map 0134; 0135; Case map 0136; 0137; Case map 0139; 013A; Case map 013B; 013C; Case map 013D; 013E; Case map
Hoffman & Blanchet Standards Track [Page 62]
RFC 3454 Preparation of Internationalized Strings December 2002
013F; 0140; Case map 0141; 0142; Case map 0143; 0144; Case map 0145; 0146; Case map 0147; 0148; Case map 0149; 02BC 006E; Case map 014A; 014B; Case map 014C; 014D; Case map 014E; 014F; Case map 0150; 0151; Case map 0152; 0153; Case map 0154; 0155; Case map 0156; 0157; Case map 0158; 0159; Case map 015A; 015B; Case map 015C; 015D; Case map 015E; 015F; Case map 0160; 0161; Case map 0162; 0163; Case map 0164; 0165; Case map 0166; 0167; Case map 0168; 0169; Case map 016A; 016B; Case map 016C; 016D; Case map 016E; 016F; Case map 0170; 0171; Case map 0172; 0173; Case map 0174; 0175; Case map 0176; 0177; Case map 0178; 00FF; Case map 0179; 017A; Case map 017B; 017C; Case map 017D; 017E; Case map 017F; 0073; Case map 0181; 0253; Case map 0182; 0183; Case map 0184; 0185; Case map 0186; 0254; Case map 0187; 0188; Case map 0189; 0256; Case map 018A; 0257; Case map 018B; 018C; Case map 018E; 01DD; Case map 018F; 0259; Case map 0190; 025B; Case map 0191; 0192; Case map 0193; 0260; Case map 0194; 0263; Case map
Hoffman & Blanchet Standards Track [Page 63]
RFC 3454 Preparation of Internationalized Strings December 2002
0196; 0269; Case map 0197; 0268; Case map 0198; 0199; Case map 019C; 026F; Case map 019D; 0272; Case map 019F; 0275; Case map 01A0; 01A1; Case map 01A2; 01A3; Case map 01A4; 01A5; Case map 01A6; 0280; Case map 01A7; 01A8; Case map 01A9; 0283; Case map 01AC; 01AD; Case map 01AE; 0288; Case map 01AF; 01B0; Case map 01B1; 028A; Case map 01B2; 028B; Case map 01B3; 01B4; Case map 01B5; 01B6; Case map 01B7; 0292; Case map 01B8; 01B9; Case map 01BC; 01BD; Case map 01C4; 01C6; Case map 01C5; 01C6; Case map 01C7; 01C9; Case map 01C8; 01C9; Case map 01CA; 01CC; Case map 01CB; 01CC; Case map 01CD; 01CE; Case map 01CF; 01D0; Case map 01D1; 01D2; Case map 01D3; 01D4; Case map 01D5; 01D6; Case map 01D7; 01D8; Case map 01D9; 01DA; Case map 01DB; 01DC; Case map 01DE; 01DF; Case map 01E0; 01E1; Case map 01E2; 01E3; Case map 01E4; 01E5; Case map 01E6; 01E7; Case map 01E8; 01E9; Case map 01EA; 01EB; Case map 01EC; 01ED; Case map 01EE; 01EF; Case map 01F0; 006A 030C; Case map 01F1; 01F3; Case map 01F2; 01F3; Case map
Hoffman & Blanchet Standards Track [Page 64]
RFC 3454 Preparation of Internationalized Strings December 2002
01F4; 01F5; Case map 01F6; 0195; Case map 01F7; 01BF; Case map 01F8; 01F9; Case map 01FA; 01FB; Case map 01FC; 01FD; Case map 01FE; 01FF; Case map 0200; 0201; Case map 0202; 0203; Case map 0204; 0205; Case map 0206; 0207; Case map 0208; 0209; Case map 020A; 020B; Case map 020C; 020D; Case map 020E; 020F; Case map 0210; 0211; Case map 0212; 0213; Case map 0214; 0215; Case map 0216; 0217; Case map 0218; 0219; Case map 021A; 021B; Case map 021C; 021D; Case map 021E; 021F; Case map 0220; 019E; Case map 0222; 0223; Case map 0224; 0225; Case map 0226; 0227; Case map 0228; 0229; Case map 022A; 022B; Case map 022C; 022D; Case map 022E; 022F; Case map 0230; 0231; Case map 0232; 0233; Case map 0345; 03B9; Case map 0386; 03AC; Case map 0388; 03AD; Case map 0389; 03AE; Case map 038A; 03AF; Case map 038C; 03CC; Case map 038E; 03CD; Case map 038F; 03CE; Case map 0390; 03B9 0308 0301; Case map 0391; 03B1; Case map 0392; 03B2; Case map 0393; 03B3; Case map 0394; 03B4; Case map 0395; 03B5; Case map 0396; 03B6; Case map
Hoffman & Blanchet Standards Track [Page 65]
RFC 3454 Preparation of Internationalized Strings December 2002
0397; 03B7; Case map 0398; 03B8; Case map 0399; 03B9; Case map 039A; 03BA; Case map 039B; 03BB; Case map 039C; 03BC; Case map 039D; 03BD; Case map 039E; 03BE; Case map 039F; 03BF; Case map 03A0; 03C0; Case map 03A1; 03C1; Case map 03A3; 03C3; Case map 03A4; 03C4; Case map 03A5; 03C5; Case map 03A6; 03C6; Case map 03A7; 03C7; Case map 03A8; 03C8; Case map 03A9; 03C9; Case map 03AA; 03CA; Case map 03AB; 03CB; Case map 03B0; 03C5 0308 0301; Case map 03C2; 03C3; Case map 03D0; 03B2; Case map 03D1; 03B8; Case map 03D5; 03C6; Case map 03D6; 03C0; Case map 03D8; 03D9; Case map 03DA; 03DB; Case map 03DC; 03DD; Case map 03DE; 03DF; Case map 03E0; 03E1; Case map 03E2; 03E3; Case map 03E4; 03E5; Case map 03E6; 03E7; Case map 03E8; 03E9; Case map 03EA; 03EB; Case map 03EC; 03ED; Case map 03EE; 03EF; Case map 03F0; 03BA; Case map 03F1; 03C1; Case map 03F2; 03C3; Case map 03F4; 03B8; Case map 03F5; 03B5; Case map 0400; 0450; Case map 0401; 0451; Case map 0402; 0452; Case map 0403; 0453; Case map 0404; 0454; Case map
Hoffman & Blanchet Standards Track [Page 66]
RFC 3454 Preparation of Internationalized Strings December 2002
0405; 0455; Case map 0406; 0456; Case map 0407; 0457; Case map 0408; 0458; Case map 0409; 0459; Case map 040A; 045A; Case map 040B; 045B; Case map 040C; 045C; Case map 040D; 045D; Case map 040E; 045E; Case map 040F; 045F; Case map 0410; 0430; Case map 0411; 0431; Case map 0412; 0432; Case map 0413; 0433; Case map 0414; 0434; Case map 0415; 0435; Case map 0416; 0436; Case map 0417; 0437; Case map 0418; 0438; Case map 0419; 0439; Case map 041A; 043A; Case map 041B; 043B; Case map 041C; 043C; Case map 041D; 043D; Case map 041E; 043E; Case map 041F; 043F; Case map 0420; 0440; Case map 0421; 0441; Case map 0422; 0442; Case map 0423; 0443; Case map 0424; 0444; Case map 0425; 0445; Case map 0426; 0446; Case map 0427; 0447; Case map 0428; 0448; Case map 0429; 0449; Case map 042A; 044A; Case map 042B; 044B; Case map 042C; 044C; Case map 042D; 044D; Case map 042E; 044E; Case map 042F; 044F; Case map 0460; 0461; Case map 0462; 0463; Case map 0464; 0465; Case map 0466; 0467; Case map 0468; 0469; Case map
Hoffman & Blanchet Standards Track [Page 67]
RFC 3454 Preparation of Internationalized Strings December 2002
046A; 046B; Case map 046C; 046D; Case map 046E; 046F; Case map 0470; 0471; Case map 0472; 0473; Case map 0474; 0475; Case map 0476; 0477; Case map 0478; 0479; Case map 047A; 047B; Case map 047C; 047D; Case map 047E; 047F; Case map 0480; 0481; Case map 048A; 048B; Case map 048C; 048D; Case map 048E; 048F; Case map 0490; 0491; Case map 0492; 0493; Case map 0494; 0495; Case map 0496; 0497; Case map 0498; 0499; Case map 049A; 049B; Case map 049C; 049D; Case map 049E; 049F; Case map 04A0; 04A1; Case map 04A2; 04A3; Case map 04A4; 04A5; Case map 04A6; 04A7; Case map 04A8; 04A9; Case map 04AA; 04AB; Case map 04AC; 04AD; Case map 04AE; 04AF; Case map 04B0; 04B1; Case map 04B2; 04B3; Case map 04B4; 04B5; Case map 04B6; 04B7; Case map 04B8; 04B9; Case map 04BA; 04BB; Case map 04BC; 04BD; Case map 04BE; 04BF; Case map 04C1; 04C2; Case map 04C3; 04C4; Case map 04C5; 04C6; Case map 04C7; 04C8; Case map 04C9; 04CA; Case map 04CB; 04CC; Case map 04CD; 04CE; Case map 04D0; 04D1; Case map 04D2; 04D3; Case map
Hoffman & Blanchet Standards Track [Page 68]
RFC 3454 Preparation of Internationalized Strings December 2002
04D4; 04D5; Case map 04D6; 04D7; Case map 04D8; 04D9; Case map 04DA; 04DB; Case map 04DC; 04DD; Case map 04DE; 04DF; Case map 04E0; 04E1; Case map 04E2; 04E3; Case map 04E4; 04E5; Case map 04E6; 04E7; Case map 04E8; 04E9; Case map 04EA; 04EB; Case map 04EC; 04ED; Case map 04EE; 04EF; Case map 04F0; 04F1; Case map 04F2; 04F3; Case map 04F4; 04F5; Case map 04F8; 04F9; Case map 0500; 0501; Case map 0502; 0503; Case map 0504; 0505; Case map 0506; 0507; Case map 0508; 0509; Case map 050A; 050B; Case map 050C; 050D; Case map 050E; 050F; Case map 0531; 0561; Case map 0532; 0562; Case map 0533; 0563; Case map 0534; 0564; Case map 0535; 0565; Case map 0536; 0566; Case map 0537; 0567; Case map 0538; 0568; Case map 0539; 0569; Case map 053A; 056A; Case map 053B; 056B; Case map 053C; 056C; Case map 053D; 056D; Case map 053E; 056E; Case map 053F; 056F; Case map 0540; 0570; Case map 0541; 0571; Case map 0542; 0572; Case map 0543; 0573; Case map 0544; 0574; Case map 0545; 0575; Case map 0546; 0576; Case map
Hoffman & Blanchet Standards Track [Page 69]
RFC 3454 Preparation of Internationalized Strings December 2002
0547; 0577; Case map 0548; 0578; Case map 0549; 0579; Case map 054A; 057A; Case map 054B; 057B; Case map 054C; 057C; Case map 054D; 057D; Case map 054E; 057E; Case map 054F; 057F; Case map 0550; 0580; Case map 0551; 0581; Case map 0552; 0582; Case map 0553; 0583; Case map 0554; 0584; Case map 0555; 0585; Case map 0556; 0586; Case map 0587; 0565 0582; Case map 1E00; 1E01; Case map 1E02; 1E03; Case map 1E04; 1E05; Case map 1E06; 1E07; Case map 1E08; 1E09; Case map 1E0A; 1E0B; Case map 1E0C; 1E0D; Case map 1E0E; 1E0F; Case map 1E10; 1E11; Case map 1E12; 1E13; Case map 1E14; 1E15; Case map 1E16; 1E17; Case map 1E18; 1E19; Case map 1E1A; 1E1B; Case map 1E1C; 1E1D; Case map 1E1E; 1E1F; Case map 1E20; 1E21; Case map 1E22; 1E23; Case map 1E24; 1E25; Case map 1E26; 1E27; Case map 1E28; 1E29; Case map 1E2A; 1E2B; Case map 1E2C; 1E2D; Case map 1E2E; 1E2F; Case map 1E30; 1E31; Case map 1E32; 1E33; Case map 1E34; 1E35; Case map 1E36; 1E37; Case map 1E38; 1E39; Case map 1E3A; 1E3B; Case map 1E3C; 1E3D; Case map
Hoffman & Blanchet Standards Track [Page 70]
RFC 3454 Preparation of Internationalized Strings December 2002
1E3E; 1E3F; Case map 1E40; 1E41; Case map 1E42; 1E43; Case map 1E44; 1E45; Case map 1E46; 1E47; Case map 1E48; 1E49; Case map 1E4A; 1E4B; Case map 1E4C; 1E4D; Case map 1E4E; 1E4F; Case map 1E50; 1E51; Case map 1E52; 1E53; Case map 1E54; 1E55; Case map 1E56; 1E57; Case map 1E58; 1E59; Case map 1E5A; 1E5B; Case map 1E5C; 1E5D; Case map 1E5E; 1E5F; Case map 1E60; 1E61; Case map 1E62; 1E63; Case map 1E64; 1E65; Case map 1E66; 1E67; Case map 1E68; 1E69; Case map 1E6A; 1E6B; Case map 1E6C; 1E6D; Case map 1E6E; 1E6F; Case map 1E70; 1E71; Case map 1E72; 1E73; Case map 1E74; 1E75; Case map 1E76; 1E77; Case map 1E78; 1E79; Case map 1E7A; 1E7B; Case map 1E7C; 1E7D; Case map 1E7E; 1E7F; Case map 1E80; 1E81; Case map 1E82; 1E83; Case map 1E84; 1E85; Case map 1E86; 1E87; Case map 1E88; 1E89; Case map 1E8A; 1E8B; Case map 1E8C; 1E8D; Case map 1E8E; 1E8F; Case map 1E90; 1E91; Case map 1E92; 1E93; Case map 1E94; 1E95; Case map 1E96; 0068 0331; Case map 1E97; 0074 0308; Case map 1E98; 0077 030A; Case map 1E99; 0079 030A; Case map
Hoffman & Blanchet Standards Track [Page 71]
RFC 3454 Preparation of Internationalized Strings December 2002
1E9A; 0061 02BE; Case map 1E9B; 1E61; Case map 1EA0; 1EA1; Case map 1EA2; 1EA3; Case map 1EA4; 1EA5; Case map 1EA6; 1EA7; Case map 1EA8; 1EA9; Case map 1EAA; 1EAB; Case map 1EAC; 1EAD; Case map 1EAE; 1EAF; Case map 1EB0; 1EB1; Case map 1EB2; 1EB3; Case map 1EB4; 1EB5; Case map 1EB6; 1EB7; Case map 1EB8; 1EB9; Case map 1EBA; 1EBB; Case map 1EBC; 1EBD; Case map 1EBE; 1EBF; Case map 1EC0; 1EC1; Case map 1EC2; 1EC3; Case map 1EC4; 1EC5; Case map 1EC6; 1EC7; Case map 1EC8; 1EC9; Case map 1ECA; 1ECB; Case map 1ECC; 1ECD; Case map 1ECE; 1ECF; Case map 1ED0; 1ED1; Case map 1ED2; 1ED3; Case map 1ED4; 1ED5; Case map 1ED6; 1ED7; Case map 1ED8; 1ED9; Case map 1EDA; 1EDB; Case map 1EDC; 1EDD; Case map 1EDE; 1EDF; Case map 1EE0; 1EE1; Case map 1EE2; 1EE3; Case map 1EE4; 1EE5; Case map 1EE6; 1EE7; Case map 1EE8; 1EE9; Case map 1EEA; 1EEB; Case map 1EEC; 1EED; Case map 1EEE; 1EEF; Case map 1EF0; 1EF1; Case map 1EF2; 1EF3; Case map 1EF4; 1EF5; Case map 1EF6; 1EF7; Case map 1EF8; 1EF9; Case map 1F08; 1F00; Case map
Hoffman & Blanchet Standards Track [Page 72]
RFC 3454 Preparation of Internationalized Strings December 2002
1F09; 1F01; Case map 1F0A; 1F02; Case map 1F0B; 1F03; Case map 1F0C; 1F04; Case map 1F0D; 1F05; Case map 1F0E; 1F06; Case map 1F0F; 1F07; Case map 1F18; 1F10; Case map 1F19; 1F11; Case map 1F1A; 1F12; Case map 1F1B; 1F13; Case map 1F1C; 1F14; Case map 1F1D; 1F15; Case map 1F28; 1F20; Case map 1F29; 1F21; Case map 1F2A; 1F22; Case map 1F2B; 1F23; Case map 1F2C; 1F24; Case map 1F2D; 1F25; Case map 1F2E; 1F26; Case map 1F2F; 1F27; Case map 1F38; 1F30; Case map 1F39; 1F31; Case map 1F3A; 1F32; Case map 1F3B; 1F33; Case map 1F3C; 1F34; Case map 1F3D; 1F35; Case map 1F3E; 1F36; Case map 1F3F; 1F37; Case map 1F48; 1F40; Case map 1F49; 1F41; Case map 1F4A; 1F42; Case map 1F4B; 1F43; Case map 1F4C; 1F44; Case map 1F4D; 1F45; Case map 1F50; 03C5 0313; Case map 1F52; 03C5 0313 0300; Case map 1F54; 03C5 0313 0301; Case map 1F56; 03C5 0313 0342; Case map 1F59; 1F51; Case map 1F5B; 1F53; Case map 1F5D; 1F55; Case map 1F5F; 1F57; Case map 1F68; 1F60; Case map 1F69; 1F61; Case map 1F6A; 1F62; Case map 1F6B; 1F63; Case map 1F6C; 1F64; Case map
Hoffman & Blanchet Standards Track [Page 73]
RFC 3454 Preparation of Internationalized Strings December 2002
1F6D; 1F65; Case map 1F6E; 1F66; Case map 1F6F; 1F67; Case map 1F80; 1F00 03B9; Case map 1F81; 1F01 03B9; Case map 1F82; 1F02 03B9; Case map 1F83; 1F03 03B9; Case map 1F84; 1F04 03B9; Case map 1F85; 1F05 03B9; Case map 1F86; 1F06 03B9; Case map 1F87; 1F07 03B9; Case map 1F88; 1F00 03B9; Case map 1F89; 1F01 03B9; Case map 1F8A; 1F02 03B9; Case map 1F8B; 1F03 03B9; Case map 1F8C; 1F04 03B9; Case map 1F8D; 1F05 03B9; Case map 1F8E; 1F06 03B9; Case map 1F8F; 1F07 03B9; Case map 1F90; 1F20 03B9; Case map 1F91; 1F21 03B9; Case map 1F92; 1F22 03B9; Case map 1F93; 1F23 03B9; Case map 1F94; 1F24 03B9; Case map 1F95; 1F25 03B9; Case map 1F96; 1F26 03B9; Case map 1F97; 1F27 03B9; Case map 1F98; 1F20 03B9; Case map 1F99; 1F21 03B9; Case map 1F9A; 1F22 03B9; Case map 1F9B; 1F23 03B9; Case map 1F9C; 1F24 03B9; Case map 1F9D; 1F25 03B9; Case map 1F9E; 1F26 03B9; Case map 1F9F; 1F27 03B9; Case map 1FA0; 1F60 03B9; Case map 1FA1; 1F61 03B9; Case map 1FA2; 1F62 03B9; Case map 1FA3; 1F63 03B9; Case map 1FA4; 1F64 03B9; Case map 1FA5; 1F65 03B9; Case map 1FA6; 1F66 03B9; Case map 1FA7; 1F67 03B9; Case map 1FA8; 1F60 03B9; Case map 1FA9; 1F61 03B9; Case map 1FAA; 1F62 03B9; Case map 1FAB; 1F63 03B9; Case map 1FAC; 1F64 03B9; Case map
Hoffman & Blanchet Standards Track [Page 74]
RFC 3454 Preparation of Internationalized Strings December 2002
1FAD; 1F65 03B9; Case map 1FAE; 1F66 03B9; Case map 1FAF; 1F67 03B9; Case map 1FB2; 1F70 03B9; Case map 1FB3; 03B1 03B9; Case map 1FB4; 03AC 03B9; Case map 1FB6; 03B1 0342; Case map 1FB7; 03B1 0342 03B9; Case map 1FB8; 1FB0; Case map 1FB9; 1FB1; Case map 1FBA; 1F70; Case map 1FBB; 1F71; Case map 1FBC; 03B1 03B9; Case map 1FBE; 03B9; Case map 1FC2; 1F74 03B9; Case map 1FC3; 03B7 03B9; Case map 1FC4; 03AE 03B9; Case map 1FC6; 03B7 0342; Case map 1FC7; 03B7 0342 03B9; Case map 1FC8; 1F72; Case map 1FC9; 1F73; Case map 1FCA; 1F74; Case map 1FCB; 1F75; Case map 1FCC; 03B7 03B9; Case map 1FD2; 03B9 0308 0300; Case map 1FD3; 03B9 0308 0301; Case map 1FD6; 03B9 0342; Case map 1FD7; 03B9 0308 0342; Case map 1FD8; 1FD0; Case map 1FD9; 1FD1; Case map 1FDA; 1F76; Case map 1FDB; 1F77; Case map 1FE2; 03C5 0308 0300; Case map 1FE3; 03C5 0308 0301; Case map 1FE4; 03C1 0313; Case map 1FE6; 03C5 0342; Case map 1FE7; 03C5 0308 0342; Case map 1FE8; 1FE0; Case map 1FE9; 1FE1; Case map 1FEA; 1F7A; Case map 1FEB; 1F7B; Case map 1FEC; 1FE5; Case map 1FF2; 1F7C 03B9; Case map 1FF3; 03C9 03B9; Case map 1FF4; 03CE 03B9; Case map 1FF6; 03C9 0342; Case map 1FF7; 03C9 0342 03B9; Case map 1FF8; 1F78; Case map
Hoffman & Blanchet Standards Track [Page 75]
RFC 3454 Preparation of Internationalized Strings December 2002
1FF9; 1F79; Case map 1FFA; 1F7C; Case map 1FFB; 1F7D; Case map 1FFC; 03C9 03B9; Case map 2126; 03C9; Case map 212A; 006B; Case map 212B; 00E5; Case map 2160; 2170; Case map 2161; 2171; Case map 2162; 2172; Case map 2163; 2173; Case map 2164; 2174; Case map 2165; 2175; Case map 2166; 2176; Case map 2167; 2177; Case map 2168; 2178; Case map 2169; 2179; Case map 216A; 217A; Case map 216B; 217B; Case map 216C; 217C; Case map 216D; 217D; Case map 216E; 217E; Case map 216F; 217F; Case map 24B6; 24D0; Case map 24B7; 24D1; Case map 24B8; 24D2; Case map 24B9; 24D3; Case map 24BA; 24D4; Case map 24BB; 24D5; Case map 24BC; 24D6; Case map 24BD; 24D7; Case map 24BE; 24D8; Case map 24BF; 24D9; Case map 24C0; 24DA; Case map 24C1; 24DB; Case map 24C2; 24DC; Case map 24C3; 24DD; Case map 24C4; 24DE; Case map 24C5; 24DF; Case map 24C6; 24E0; Case map 24C7; 24E1; Case map 24C8; 24E2; Case map 24C9; 24E3; Case map 24CA; 24E4; Case map 24CB; 24E5; Case map 24CC; 24E6; Case map 24CD; 24E7; Case map 24CE; 24E8; Case map
Hoffman & Blanchet Standards Track [Page 76]
RFC 3454 Preparation of Internationalized Strings December 2002
24CF; 24E9; Case map FB00; 0066 0066; Case map FB01; 0066 0069; Case map FB02; 0066 006C; Case map FB03; 0066 0066 0069; Case map FB04; 0066 0066 006C; Case map FB05; 0073 0074; Case map FB06; 0073 0074; Case map FB13; 0574 0576; Case map FB14; 0574 0565; Case map FB15; 0574 056B; Case map FB16; 057E 0576; Case map FB17; 0574 056D; Case map FF21; FF41; Case map FF22; FF42; Case map FF23; FF43; Case map FF24; FF44; Case map FF25; FF45; Case map FF26; FF46; Case map FF27; FF47; Case map FF28; FF48; Case map FF29; FF49; Case map FF2A; FF4A; Case map FF2B; FF4B; Case map FF2C; FF4C; Case map FF2D; FF4D; Case map FF2E; FF4E; Case map FF2F; FF4F; Case map FF30; FF50; Case map FF31; FF51; Case map FF32; FF52; Case map FF33; FF53; Case map FF34; FF54; Case map FF35; FF55; Case map FF36; FF56; Case map FF37; FF57; Case map FF38; FF58; Case map FF39; FF59; Case map FF3A; FF5A; Case map 10400; 10428; Case map 10401; 10429; Case map 10402; 1042A; Case map 10403; 1042B; Case map 10404; 1042C; Case map 10405; 1042D; Case map 10406; 1042E; Case map 10407; 1042F; Case map 10408; 10430; Case map
Hoffman & Blanchet Standards Track [Page 77]
RFC 3454 Preparation of Internationalized Strings December 2002
10409; 10431; Case map 1040A; 10432; Case map 1040B; 10433; Case map 1040C; 10434; Case map 1040D; 10435; Case map 1040E; 10436; Case map 1040F; 10437; Case map 10410; 10438; Case map 10411; 10439; Case map 10412; 1043A; Case map 10413; 1043B; Case map 10414; 1043C; Case map 10415; 1043D; Case map 10416; 1043E; Case map 10417; 1043F; Case map 10418; 10440; Case map 10419; 10441; Case map 1041A; 10442; Case map 1041B; 10443; Case map 1041C; 10444; Case map 1041D; 10445; Case map 1041E; 10446; Case map 1041F; 10447; Case map 10420; 10448; Case map 10421; 10449; Case map 10422; 1044A; Case map 10423; 1044B; Case map 10424; 1044C; Case map 10425; 1044D; Case map ----- End Table B.3 -----
The tables in this appendix consist of lines with one prohibited code point per line. The format of the lines are the value of the code point, a semicolon, and a comment which is the name of the code point.
----- Start Table C.1.1 ----- 0020; SPACE ----- End Table C.1.1 -----
Hoffman & Blanchet Standards Track [Page 78]
RFC 3454 Preparation of Internationalized Strings December 2002
C.1.2 Non-ASCII space characters ----- Start Table C.1.2 ----- 00A0; NO-BREAK SPACE 1680; OGHAM SPACE MARK 2000; EN QUAD 2001; EM QUAD 2002; EN SPACE 2003; EM SPACE 2004; THREE-PER-EM SPACE 2005; FOUR-PER-EM SPACE 2006; SIX-PER-EM SPACE 2007; FIGURE SPACE 2008; PUNCTUATION SPACE 2009; THIN SPACE 200A; HAIR SPACE 200B; ZERO WIDTH SPACE 202F; NARROW NO-BREAK SPACE 205F; MEDIUM MATHEMATICAL SPACE 3000; IDEOGRAPHIC SPACE ----- End Table C.1.2 -----
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 90]
RFC 3454 Preparation of Internationalized Strings December 2002
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Acknowledgement
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