Each line of the ascii plaintext has been encrypted by xoring with the same randomly generated key pad, then encoded in hex. Your task is to decrypt as much of it as possible. You should at least be able to get the entire last line.
Please submit your code and writeup to Gradescope before class on October 10. Your code should be named hw1-sol.py, and your writeup should be named hw1-solutions.pdf. You may discuss this assignment in small groups with classmates, but please code and write up your solutions yourself. Please credit any collaborators you discussed with and any references you used.
Start early! This assignment will take longer than you think.
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import os
MSGS = open("hw1-message.txt").readlines()
def bytexor(a, b): # xor two byte arrays (trims the longer input)
return bytes([x ^ y for (x,y) in zip (a,b)])
def random(size=16):
return os.urandom(size)
def encrypt(key, msg):
c = bytexor(key, msg)
print(c.hex())
return c
def main():
key = random(1024)
ciphertexts = [encrypt(key, msg.encode('utf-8')) for msg in MSGS]
return ciphertexts
if __name__=='__main__':
main()