# 密钥编排函数
def KSA(key):
    S = []        # 状态数组
    T = []        # 临时数组
    #初始化S和T
    for i in range(256):
        S.append(i)
        T.append(key[i % len(key)])
    # print(S,T)

    #用T产生S的初始置换
    j = 0
    for i in range(256):
        j = (j + S[i] + ord(T[i])) % 256
        S[i],S[j] = S[j],S[i]   #交换S[i] 和 S[j]
    # print(S,T)
    return S

#密钥流生成函数
def generateKey(S,M):
    Ks = []
    i = j = 0
    for _ in range(len(M)):
        i = (i + 1) % 26
        j = (j + S[i]) % 256
        S[i],S[j] = S[j],S[i]
        t = (S[i] + S[j]) % 256
        Ks.append(t)
    return Ks

# 加密函数
def Rc4_encode(M,key):
    C = ""
    S = KSA(key)    # 密钥编排
    Ks = generateKey(S,M)
    for i in range(len(M)):
        C += chr(ord(M[i]) ^ S[Ks[i]])
    return C
    
# 解密函数
def Rc4_decode(C,key):
    M = ""
    S = KSA(key)    # 密钥编排
    Ks = generateKey(S,C)
    for i in range(len(C)):
        M += chr(ord(C[i]) ^ S[Ks[i]])
    return M

key = 'no-so-random-key'
m = 'Good you are corrent'

C = Rc4_encode(m,key)
print("加密后密文：" , C)

M = Rc4_decode(C,key)
print("解密后明文：",M)

• 1
• 2
• 3
• 4
• 5
• 6
• 7
• 8
• 9
• 10
• 11
• 12
• 13
• 14
• 15
• 16
• 17
• 18
• 19
• 20
• 21
• 22
• 23
• 24
• 25
• 26
• 27
• 28
• 29
• 30
• 31
• 32
• 33
• 34
• 35
• 36
• 37
• 38
• 39
• 40
• 41
• 42
• 43
• 44
• 45
• 46
• 47
• 48
• 49
• 50
• 51
• 52
• 53
• 54
• 55
• 56
• 57