Subject: Re: [Fwd: Re: Kerberos Revisions and UTF8]

From: Jeffrey Altman <[email-masked]>
Date: Wed, 8 Aug 2001 10:48:32 EDT

Nico:

Its not a question of UTF-8 co-existing with ASCII.  Yes, 7-bit UTF-8
is ASCII.

The problem is that GeneralString means ISO-2022 encoded strings.
ASCII is an ISO-2022 encoded string.  UTF-8 is not UNLESS it is
prefixed by the ISO-2022 escape to UTF-8 sequence.  Therefore, in
order for UTF-8 strings to be placed in a GeneralString the contents
of GeneralString MUST be 

  <ESC>%G[UTF-8 String]

ISO-2022 is used to allow a series of octets to represent characters
from multiple 8-bit character sets.  The sequence starts off as ASCII
and then can be switched into other ISO standard and non-ISO standard
characters with different escape sequences.  ISO 2022 is most commonly
known for its use in DEC VT and other ANSI X3.64-1979/ISO 1649/ECMA 48
based terminals.  However, it is a general mechanism for handling the
issues associated with the need to represent a larger number of
characters than can be fit within a single octet.

- Jeff

> Can't UTF-8 and ASCII co-exist?
> 
> I.e., if a string contains only ASCII characters then it should be
> interpreted as being ASCII, whereas if a string contains any octets
> with the high bit set then it should be interpreted as being UTF-8.
> 
> Isn't a UTF-8 string containing no octects with the high bit set the
> same as an ASCII string consisting of the same octects?
> 
> Pardon my ignorance of UTF-8...
> 
> Nico
> --

 Jeffrey Altman * Sr.Software Designer      C-Kermit 8.0 Beta available
 The Kermit Project @ Columbia University   includes Secure Telnet and FTP
 http://www.kermit-project.org/             using Kerberos, SRP, and 
 [email-masked]          OpenSSL.  SSH soon to follow.

---

From: Nicolas Williams <[email-masked]>
Date: Wed, 8 Aug 2001 11:04:29 -0400

Ah.

Then:

    . Stick with GeneralString but break the rules for its use and
      require unescaped UTF8

sounds like the way to go...

Nico

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