GNU Libidn 0.5.0 alpha released (fwd)

From: Frederick Noronha (FN) (fred_at_bytesforall.org)
Date: 06/27/04

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    Date: Sun, 27 Jun 2004 05:53:19 CST
    
    

    ---------- Forwarded message ----------

    Hello. This release add some code to detect the "problem sequences"
    discussed in UTC's public review issue #29. To perhaps explain this
    in less obfuscated terms, here follow some paragraphs from the manual:

          A deficiency in the specification of Unicode Normalization Forms
       has been found. The consequence is that some strings can be
       normalized into different strings by different implementations. In
       other words, two different implementations may return different
       output for the same input (because the interpretation of the
       specification is ambiguous). Further, an implementation invoked
       again on the one of the output strings may return a different
       string (because one of the interpretation of the ambiguous
       specification make normalization non-idempotent). Fortunately,
       only a select few character sequence exhibit this problem, and none
       of them are expected to occur in natural languages (due to
       different linguistic uses of the involved characters).

          A full discussion of the problem may be found at
       `http://www.unicode.org/review/pr-29.html'.

          The PR29 functions below allow you to detect the problem
       sequence. So when would you want to use these functions? For most
       applications, such as those using Nameprep for IDN, this is likely
       only to be an interoperability problem. Thus, you may not want to
       care about it, as the character sequences will rarely occur
       naturally. However, if you are using a profile, such as SASLPrep,
       to process authentication tokens; authorization tokens; or
       passwords, there is a real danger that attackers may try to use the
       peculiarities in these strings to attack parts of your system. As
       only a small number of strings, and no naturally occurring strings,
       exhibit this problem, the conservative approach of rejecting the
       strings is recommended. If this approach is not used, you should
       instead verify that all parts of your system, that process the
       tokens and passwords, use a NFKC implementation that produce the
       same output for the same input.

    Regards,
    Simon

    GNU Libidn is an implementation of the Stringprep, Punycode and IDNA
    specifications defined by the IETF Internationalized Domain Names
    (IDN) working group, used for internationalized domain names. The
    library contains a generic Stringprep implementation that does Unicode
    3.2 NFKC normalization, mapping and prohibitation of characters, and
    bidirectional character handling. Profiles for Nameprep, iSCSI, SASL
    and XMPP are included. Punycode and ASCII Compatible Encoding (ACE)
    via IDNA are supported. A mechanism to define Top-Level Domain (TLD)
    specific validation tables, and to compare strings against those
    tables, is included. Default tables for some TLDs are also included.

    Here are the compressed sources:
      ftp://alpha.gnu.org/gnu/libidn/libidn-0.5.0.tar.gz (1.8MB)
      http://josefsson.org/libidn/releases/libidn-0.5.0.tar.gz (1.8MB)

    Here are GPG detached signatures:
      ftp://alpha.gnu.org/gnu/libidn/libidn-0.5.0.tar.gz.sig
      http://josefsson.org/libidn/releases/libidn-0.5.0.tar.gz.sig

    Here are the build reports for various platforms:
      http://josefsson.org/autobuild/libidn.html

    Here are the MD5 and SHA1 signatures:

    d13633479facc9163eb16db6f9662a3b libidn-0.5.0.tar.gz
    ec010fed2ae4843e5651239f15fddbba libidn-0.5.0.tar.gz.sig
    6a4189656fbbc8efb65d5454e8e1ba7005ef639f libidn-0.5.0.tar.gz
    9fb995669d2c1cc8996beaaccf911193fb5545fe libidn-0.5.0.tar.gz.sig

    Noteworthy changes since version 0.4.9 (the last version announced here):

    * Version 0.5.0 (unreleased)

    ** Functions to detect "normalization problem sequences" as per PR-29 added.
    See the new chapter "PR29 Functions" in the manual
    (doc/libidn.{ps,pdf,html}) for more information and the background
    story. An external link that discuss the problem is
    <http://www.unicode.org/review/pr-29.html>.

    ** More translations.
    Added Esperanto (by Edmund GRIMLEY EVANS).

    ** API and ABI is backwards compatible with the previous version.
    pr29.h: ADD. Prototypes for PR29 types and functions.
    pr29_4, pr29_4z, pr29_8z: ADD. New API entry points for PR29 functions.
    Pr29_rc: ADD. New error code enum type for PR29 functions.

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    Relevant Pages

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