Last Block Encryption Think This is More Secure

[Adrian Verkuil]

I call this LBCBFBB ,last block cypertext borrow from before block

more secure then adding zero's or other know pad methods.
so why shall we give someone know plaintext to play with?
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last block procedure

LOCAL pad$ , before$
before$=sMessage
GET$ #1, LastBlockSize , sMessage


IF (LEN(sMessage) MOD 16) <> 0 THEN
' is not mod 16 so now we borrow the pad bytes from the previous block of already ENCODED plaintext.

IF EnCode=1 THEN
pad$=RIGHT$(WorkString,16) ' from memory just encoded (so encoded plaintext)

ELSE
pad$=RIGHT$(before$,16) ' from disk not yet decoded (so encoded plaintext)
END IF

FOR i = 1 TO 16 - (LEN(sMessage) MOD 16) ' pad the string to mod 16
sMessage = sMessage + MID$(pad$,i,1)
NEXT
END IF

Ok Guys Shoot At It, Better Methods Welcome