Indetectables

Código: Seleccionar todo

 import unicodedata
  
 def ini_caja(clave):
     S = range(256)
     K = range(256)
     j = 0
     for i in range(256):
         if (j==len(clave)):
             j = 0
         K[i] = ord(clave[j])
         j = j+1
    
     j = 0
     for i in range(255):
         j = (j+S[i]+K[i])%256
         aux = S[i]
         S[i] = S[j]
         S[j] = aux
    
     return S
  
  
 def rc4(nomfich, nomdest, clave):
     S = ini_caja(clave)
     dest = open(nomdest, 'w')
     data = open(nomfich, 'r')
     data.seek(0,2)
     tam = data.tell()
     data.seek(0,0)
     i, j = 0, 0
     while(data.tell() < tam):
         i = (i+1)%256
         j = (j+1)%256
         aux = S[i]
         S[i] = S[j]
         S[j] = aux
         t = (S[i] + S[j])%256
         O = S[t]
         b = data.read(1)
         w = O ^ ord(b)
         dest.write(chr(w))