mirror of
https://github.com/apprenticeharper/DeDRM_tools
synced 2024-11-18 21:25:39 +00:00
20bc936e99
The first unified calibre plugin
31 lines
853 B
Python
31 lines
853 B
Python
#!/usr/bin/env python
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# vim:ts=4:sw=4:softtabstop=4:smarttab:expandtab
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def load_pycrypto():
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try :
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from Crypto.Cipher import DES as _DES
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except:
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return None
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class DES(object):
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def __init__(self, key):
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if len(key) != 8 :
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raise Error('DES improper key used')
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self.key = key
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self._des = _DES.new(key,_DES.MODE_ECB)
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def desdecrypt(self, data):
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return self._des.decrypt(data)
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def decrypt(self, data):
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if not data:
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return ''
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i = 0
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result = []
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while i < len(data):
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block = data[i:i+8]
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processed_block = self.desdecrypt(block)
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result.append(processed_block)
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i += 8
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return ''.join(result)
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return DES
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