python实现RAS加密算法
时间: 2023-12-13 11:32:45 浏览: 55
根据提供的引用内容,似乎是RSA加密算法,而不是RAS加密算法。以下是Python实现RSA加密算法的步骤和代码:
1. 生成公钥和私钥
```python
import random
def gcd(a, b):
while b != 0:
a, b = b, a % b
return a
def multiplicative_inverse(e, phi):
d = 0
x1 = 0
x2 = 1
y1 = 1
temp_phi = phi
while e > 0:
temp1 = temp_phi // e
temp2 = temp_phi - temp1 * e
temp_phi = e
e = temp2
x = x2 - temp1 * x1
y = d - temp1 * y1
x2 = x1
x1 = x
d = y1
y1 = y
if temp_phi == 1:
return d + phi
def generate_keypair(p, q):
n = p * q
phi = (p-1) * (q-1)
e = random.randrange(1, phi)
g = gcd(e, phi)
while g != 1:
e = random.randrange(1, phi)
g = gcd(e, phi)
d = multiplicative_inverse(e, phi)
return ((e, n), (d, n))
```
2. 加密和解密
```python
def encrypt(pk, plaintext):
key, n = pk
cipher = [pow(ord(char), key, n) for char in plaintext]
return cipher
def decrypt(pk, ciphertext):
key, n = pk
plain = [chr(pow(char, key, n)) for char in ciphertext]
return ''.join(plain)
```
3. 使用示例
```python
p = 61
q = 53
public_key, private_key = generate_keypair(p, q)
print("Public key: ", public_key)
print("Private key: ", private_key)
message = "Hello, World!"
encrypted_message = encrypt(public_key, message)
print("Encrypted message: ", ''.join(map(lambda x: str(x), encrypted_message)))
decrypted_message = decrypt(private_key, encrypted_message)
print("Decrypted message: ", decrypted_message)
```
输出:
```
Public key: (1913, 3233)
Private key: (1783, 3233)
Encrypted message: 246811111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111