#NIST #FF1 #FPE Just a test with format-preserving encryption. Used here, a 256bit key and a 64bit nonce.

$ echo "a little test ..." | xxd -p
61206c6974746c652074657374202e2e2e0a

$ echo "a little test ..." | xxd -p | ff1 -k key2 -t tweak
c79a73f13bde057d1d6d9ca82ec030bc4533