18 lines
421 B
Python
18 lines
421 B
Python
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class PKCS7:
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BLOCKSIZE = 16
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@staticmethod
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def pad(data, bs=BLOCKSIZE):
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l = len(data)
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n = bs-l%bs
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v = bytes([n])
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return data+v*n
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@staticmethod
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def unpad(data, bs=BLOCKSIZE):
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l = len(data)
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n = data[-1]
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if n > bs:
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raise ValueError("Cannot unpad, invalid padding length of "+str(n)+" bytes")
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else:
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return data[:l-n]
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