Name: Anonymous 2009-04-29 18:35
Can someone explain to me how i would go about doing this?
Let the user enter and encryption key consisting of multiple characters. Use this key to encrypt and decrypt the plain-text by XORing each character of the key against a correponding byte in the message. Repeat the key as many times a necessary untill all plain-text bytes are translated.
Hopefully I didn't fail to bad at life...
Let the user enter and encryption key consisting of multiple characters. Use this key to encrypt and decrypt the plain-text by XORing each character of the key against a correponding byte in the message. Repeat the key as many times a necessary untill all plain-text bytes are translated.
KEY = 239
BUFMAX = 128
.data
sPrompt BYTE "Enter the plain text: ",0
sEncrypt BYTE "Cipher text: ",0
sDecrypt BYTE "Decrypted: ",0
buffer BYTE BUFMAX+1 DUP(0)
bufSize DWORD ?
.code
main PROC
call InputTheString
call TranslateBuffer
mov edx,OFFSET sEncrypt
call DisplayMessage
call TranslateBuffer
mov edx,OFFSET sDecrypt
call DisplayMessage
exit
main ENDP
pushad
mov edx,OFFSET sPrompt
call WriteString
mov ecx,BUFMAX
mov edx,OFFSET buffer
call ReadString
mov bufSize,eax
call Crlf
popad
ret
InputTheString ENDP
pushad
call WriteString
mov edx, OFFSET buffer
call WriteString
call Crlf
call Crlf
popad
ret
DisplayMessage ENDP
pushad
mov ecx,bufSize
mov esi,0
L1:
xor buffer[esi],Key
inc esi
loop L1
popad
ret
TranslateBuffer ENDP
END mainHopefully I didn't fail to bad at life...