The RC4 algorithm implemented in Python _python

In my spare time, I implemented the RC4 algorithm with Python.

Coding UTF-8

Class method

#/usr/bin/python #coding =utf-8 Import sys,os,hashlib,time,base64 class Rc4:def __init__ (Self,public_key = None,ckey_ Lenth =: Self.ckey_lenth = ckey_lenth Self.public_key = Public_key or ' none_public_key ' key = HASHLIB.MD5 ( Self.public_key). Hexdigest () Self.keya = Hashlib.md5 (key[0:16)). Hexdigest () Self.keyb = HASHLIB.MD5 (key[16:32]). He Xdigest () Self.keyc = ' def encode (self,string): SELF.KEYC = Hashlib.md5 (str (time.time ()). Hexdigest () [32-se  LF.CKEY_LENTH:32] string = ' 0000000000 ' + hashlib.md5 (string + self.keyb). Hexdigest () [0:16] + string self.result = ' Self.docrypt (String) return SELF.KEYC + Base64.b64encode (self.result) def decode (self,string): Self.key c = string[0:self.ckey_lenth] string = Base64.b64decode (string[self.ckey_lenth:]) Self.result = ' Self.docryp T (string) result = Self.result if (result[0:10] = = ' 0000000000 ' or int (result[0:10])-Int (Time.time ()) > 0) D result[10:26] = = HASHLIB.MD5 (result[26:] + self.keyb). Hexdigest () [0:16]: return result[26:] Else:return None def docrypt (sel f,string): String_lenth = Len (string) result = ' box = List (range (256)) Randkey = [] Cryptkey = self . Keya + hashlib.md5 (Self.keya + self.keyc). Hexdigest () Key_lenth = Len (cryptkey) for I in Xrange (255): Rand
      Key.append (Ord (cryptkey[i% key_lenth]) for I in Xrange (255): j = 0 J = (j + box[i] + randkey[i])% 256 TMP = Box[i] box[i] = box[j] box[j] = tmp for i in Xrange (string_lenth): a = j = 0 A = (A + 1)% 256 J = (j + box[a])% 256 TMP = Box[a] box[a] = box[j] box[j] = tmp Self.result +

 = Chr (ord (String[i]) ^ (box[(Box[a] + box[j))% 256])

Test:

rc = RC4 (' Nishidahuaidan ')
string = ' I'm here, where are you? '
print (string)
str = Rc.encode (string)
print (str)
str = rc.decode (str)
print (str)

function mode

#/usr/bin/python #coding =utf-8 Import sys,os,hashlib,time,base64 def RC4 (string, op = ' encode ', Public_key = ' ddd ', exp
  Irytime = 0): Ckey_lenth = 4 Public_key = Public_key and Public_key or ' key = Hashlib.md5 (Public_key). Hexdigest () Keya = HASHLIB.MD5 (Key[0:16]). Hexdigest () keyb = HASHLIB.MD5 (key[16:32]). Hexdigest () KEYC = Ckey_lenth and (op = d Ecode ' and String[0:ckey_lenth] or hashlib.md5 (str (time.time ()). Hexdigest () [32-ckey_lenth:32]) or ' Cryptkey = Keya + HASHLIB.MD5 (Keya + keyc). Hexdigest () Key_lenth = Len (cryptkey) string = Op = = ' decode ' and Base64.b64decode (string[4
  :] or ' 0000000000 ' + hashlib.md5 (string + keyb). Hexdigest () [0:16] + string string_lenth = Len (string) result = ' box = List (range (256)) Randkey = [] for i-xrange (255): Randkey.append (Ord (cryptkey[i% key_lenth])) for I I

  n xrange (255): j = 0 J = (j + box[i] + randkey[i])% 256 TMP = Box[i] box[i] = box[j] box[j] = tmp For I in Xrange (string_lEnth): a = j = 0 A = (A + 1)% 256 J = (j + box[a])% 256 TMP = Box[a] box[a] = box[j] box[j] = TM P Result + = Chr (ord (String[i]) ^ (box[(Box[a] + box[j])% 256]) if op = = ' decode ': if (result[0:10) = = ' 000000 0000 ' or int (result[0:10])-Int (Time.time ()) > 0) and result[10:26] = = HASHLIB.MD5 (result[26:] + keyb). Hexdigest () [0:1

 6]: Return result[26:] Else:return None else:return KEYC + base64.b64encode (Result)

Test:

String = ' I'm here, where are you? '
print (string)
str = RC4 (string, ' encode ')
print (str)
rc = RC4 (str, ' decode ')
Print (RC)