> I repeat.  This statement is BS.  A shadow password file contains a
> PLAIN TEXT PASSWORD that you can compare against.

No it doesn't and it never has.  A UNIX shadow password file contains
either an encrypted version of a know string using the password as the
encryption key, or a MD5 (or similar) hash of the original password.
Both methods fudge things a bit so there is more that one string/hash
for any given password.  The orignal password is never stored and both
methods are one way, you can't recreate the password from the string
or hash.

When a user tries to login the plain text password they supply is used
to encrypt the known string or generate a MD5 hash.  The string/hash
is then compared against the stored version and if it matches the
password was good.

Shadow password files exist to protect the strings/hashes.  In the
good old days they were stored the password file.  But as computers
got faster it became possible brute force crack passwords.  Basically
you generate all the possible strings/hashes for, say, "sex" and
search for them in the password file.  So the shadow password file was
created to limit access to the strings/hashes.

Bottom line: UNIX never stores the plain text password.

->Spike

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