Crypt::xDBM_File encrypts/decrypts the data in a gdbm, ndbm, sdbm (and
maybe even berkeleyDB, but I didn't test that) file. It gets tied to a
hash and you just access the hash like normal. The crypt function can
be any of the CPAN modules that use encrypt, decrypt, keysize, blocksize
(so Crypt::IDEA, Crypt::DES, Crypt::Blowfish, ... should all work)

***IMPORTANT*** Encryption keys (the key you pass in on the tie line)
will be padded or truncated to fit the keysize(). Data (the key/values of
the hash) is padded to fill complete blocks of blocksize().

The padding is stripped before being returned to the user so you shouldn't
need to worry about it (except truncated keys). Read the doc that comes
with crypt function to get an idea of what these sizes are. If keysize
or blocksize returns a zero the default is set to 8 bytes (64 bits).

WWW: http://search.cpan.org/dist/Crypt-xDBM_File/