实现rc4库
非常简洁，看代码吧
代码语言：javascript复制import base64
import hashlib
import os
from io import BytesIO
class RC4(object):
def __init__(self, key=None):
self.key = hashlib.md5(key.encode("utf-8")).hexdigest()
def encode(self, in_stream, out_stream):
sbox = self.sbox()
while 1:
chunk = in_stream.read(8)
if not chunk:
break
out_chuck = bytearray()
for bt in chunk:
out_chuck.append(bt ^ next(sbox))
out_stream.write(bytes(out_chuck))
def sbox(self):
keylength = len(self.key)
s = list(range(256)) # init S box
j = 0
for i in range(255):
j = (j s[i] ord(self.key[i % keylength])) % 256
s[i], s[j] = s[j], s[i]
i = 0
j = 0
while 1:
i = (i 1) % 256
j = (j s[i]) % 256
s[i], s[j] = s[j], s[i]
yield s[(s[i] s[j]) % 256]
def encrypt(in_stream: BytesIO, out_stream: BytesIO, pwd: str):
rc4_cryptor = RC4(pwd)
rc4_cryptor.encode(in_stream, out_stream)
def encrypt_str(data: str, pwd: str):
in_stream = BytesIO()
out_stream = BytesIO()
data_bytes = data.encode("utf-8")
# 引入随机IV打乱原文
iv = os.urandom(1)[0]
tp_v = iv
data_xor_iv = bytearray()
for bt in data_bytes:
data_xor_iv.append(bt ^ tp_v)
tp_v = bt ^ tp_v
in_stream.write(data_xor_iv)
in_stream.seek(0)
encrypt(in_stream, out_stream, pwd)
enc_bytes = bytes([iv]) out_stream.getvalue()
b64_str = base64.urlsafe_b64encode(enc_bytes)
return b64_str.decode("utf-8")
def decrypt_str(data: str, pwd: str):
data_bytes = base64.urlsafe_b64decode(data)
in_stream = BytesIO()
out_stream = BytesIO()
iv = data_bytes[:1][0]
in_stream.write(data_bytes[1:])
in_stream.seek(0)
encrypt(in_stream, out_stream, pwd)
dec_bytes = out_stream.getvalue()
data_xor_iv = bytearray()
for bt in dec_bytes:
data_xor_iv.append(bt ^ iv)
iv = bt
return data_xor_iv.decode('utf-8')
if __name__ == "__main__":
test_byte_data = "hello world 世界你好"
ret = encrypt_str(test_byte_data, 'yzh')
print(ret)
ret = decrypt_str(ret, 'yzh')
print(ret)
assert test_byte_data == ret
ret = encrypt_str("1#1500000000", 'yzh')
print(ret, len(ret))
ret = encrypt_str("111111#1500000000", 'yzh')
print(ret, len(ret))
ret = encrypt_str("99999999#1500000000", 'yzh')
print(ret, len(ret))
