All of /usr/bin/*sum utilities produce very similar output
consisting of a long number of hex-digits, so that later one can't
instantly understand what type of hash it is.
It was acceptable in the old md5sum-only days, but now it causes
much confusion. For example, see RedHat bug #515715.
Of course, one can count the number of digits, but a) that's
weird; b) different algorythms can use equal hash length.
The problem would be eliminated if *sum utils could prefix hashes
with "type-tag", similarly to what is done in /etc/shadow. For example,
"sha1:..." or "sha1/...".
(And that is THE RIGHT THING -- data of unknown type is bad, so http
introduced "Content-type:" header, PGP includes "Hash:" prefix, etc. With
current diversity of hash types, that becomes the barest necessity for
*sum utils too...)
(Of curse, for compatibility reasons, that have to be switched on
explicitly -- e.g., with "-l" (Label). And besides adding such tags, *sum
have to understand such prefixes, but that's trivial.)
_________________________________________
Dmitry Yu. Bolkhovityanov
The Budker Institute of Nuclear Physics
Novosibirsk, Russia
