The cypher works by finding the Exclusive OR of each character with a key string. Here it is in Python.
# Vernam cypher demo
# T Street 2015-10-16
def makeVernamCypher( text, key ):
""" Returns the Vernam Cypher for given string and key """
answer = "" # the Cypher text
p = 0 # pointer for the key
for char in text:
answer += chr(ord(char) ^ ord(key[p]))
p += 1
if p==len(key):
p = 0
return answer
MY_KEY = "cvwopslweinedvq9fnasdlkfn2"
while True:
print("\n\n---Vernam Cypher---")
PlainText = input("Enter text to encrypt: ")
# Encrypt
Cypher = makeVernamCypher(PlainText, MY_KEY)
print("Cypher text: "+Cypher)
# Decrypt
decrypt = makeVernamCypher(Cypher, MY_KEY)
print("Decrypt: "+decrypt)
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| Demo shows the text has been encrypted and then decrypted again. |
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#Cyper #Vernam #Encryption