[python] Crypto

下午試了一下Crypto的東西，來寫一下筆記

參考1


From Crypto.Cipher import DES
shared_key = '12345678'    # 這個一定要是8的倍數
obj = DES.new(shared_key, MODE_ECB)
plain_text = 'hello, welcome to the world'   # plain_text 應為8的倍數

#encrypt
padding = '$'
extra = len(plain_text) % 8
if extra:
   plain_text += padding * (8-extra)
ciph_text = obj.encrypt(plain_text)

#decript
origin_text = obj.decrypt(ciph_text)
print origin_text.strip('$')


註1：可以在sharedkey上動手腳，改為 binary string
註2：strip() 是去掉所有的 padding, 所以先確保該padding不在plain_text中

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