'''
Created _disibledevent=>
@author: shanks
'''
def rc4(data, key):
'''
data: data that to be encrypted or decrypted.
key: key to encrypt or decrypt.
'''
#some parameters check here ...
#if the data is a string, convert to hex format.
if(type(data) is type("string")):
tmpData=data
data=[]
for tmp in tmpData:
data.append(ord(tmp))
#if the key is a string, convert to hex format.
if(type(key) is type("string")):
tmpKey=key
key=[]
for tmp in tmpKey:
key.append(ord(tmp))
#the Key-Scheduling Algorithm
x = 0
box= list(range(256))
for i in range(256):
x = (x + box[i] + key[i % len(key)]) % 256
box[i], box[x] = box[x], box[i]
#the Pseudo-Random Generation Algorithm
x = 0
y = 0
out = []
for c in data:
x = (x + 1) % 256
y = (y + box[x]) % 256
box[x], box[y] = box[y], box[x]
out.append(c ^ box[(box[x] + box[y]) % 256])
result=""
printable=True
for tmp in out:
if(tmp<;0x21 or tmp>0x7e):
# there is non-printable character
printable=False
break
result += chr(tmp)
if(printable==False):
result=""
#convert to hex string
for tmp in out:
result += "{0:02X}".format(tmp)
return result
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