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path: root/final/rsa-decrypt.py
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encrypted = [405, 35, 133, 371, 435, 279] # Directly from demo output of encrypted
p = 29
q = 17
n = p*q
tot = (p-1)*(q-1)
e = 3

# Calculate d such that ed == 1 mod tot
d = 1 # Guess
while (e*d % tot != 1):
  d += 1
# Algorithm is currently extremely dumb

def decrypt_block(blk):
  return blk**d % n

decrypted = [decrypt_block(block) for block in encrypted]

messagenum = 0
for blockind in range(len(decrypted)):
  block = decrypted[blockind]
  messagenum += block * n ** blockind

message = ''
while messagenum > 0:
  message = chr(messagenum%128) + message
  messagenum = (messagenum-messagenum%128)//128

print(message)