[openssl-users] Case-sensitive cipher names are a bad idea

Steven J. Hathaway shathawa at e-z.net
Sun Jan 18 05:19:00 UTC 2015

On 8/15/2014 10:10 PM, Jeffrey Walton wrote:
> On Sat, Aug 16, 2014 at 12:08 AM,<shathawa at e-z.net>  wrote:
>>> ...
>> Even today with Unicode character set families, the ability to provide
>> a global case-independent mapping becomes a massive problem. There are
>> a variety of latin-like alphabets and greek alphabets, and even
>> IBM EBCDIC encodings that are much unlike the US-ASCII character set.
>> Even more problematic are the cyrillic, hebrew, aramaic, asian, and
>> african alphabets.  Do we need to accept transliteration to these
>> various alphabetic schems?
>> Traditionally, case-independence has been the conversion of US-ASCII
>> and IBM EBCDIC encodings for named strings.  In documentation languages,
>> the use of various Unicode tablular character sets are used.
>> How much of this above work needs to be accomplished so that
>> name case-independent and character code table independence needs
>> to be accomplished.  Or should we just define a character encoding
>> standard for the naming conventions and stick to the definitions?
> I believe they are discussing strings like used in cipher suites (for
> example, "RC4-MD5"). They are 8-bit clean.
> For the upcoming hostname matching gear, IDNs must be A-label form
> from RFC 6125, section 6.4.2.
> Jeff
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The general practice is to use 7-bit US_ASCII encoding or a transcoding 
into one of
the transparent EBCDIC encoding for some mainframes based on IBM technology.

Case independence is easy if you restrict yourself to the above code tables.
Once you move to UTF-8 which may require an "8-bit clean" transmission,
the multi-byte content maps to a set of unicode characters in the range of
0x0001 - 0x10FFFF.  There are a wide number of

The older SIXBIT character system may still be in use on some systems, 
but is
mostly obsolete.

Steven J. Hathaway

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