利用cryptography库使用AES加密算法对数据进行加密和解密的具体程序300行长代码

在Python中，我们可以使用`cryptography`库来实现AES（Advanced Encryption Standard）加密和解密。下面是一个示例程序，展示如何创建一个简单的AES加密器和解密器：

from cryptography.hazmat.primitives.ciphers import Cipher, algorithms, modes
from cryptography.hazmat.primitives.kdf.pbkdf2 import PBKDF2HMAC
from cryptography.hazmat.backends import default_backend
import base64

# 导入密码和盐
password = b'secret_password'
salt = b'salt_example'

# 使用PBKDF2HMAC生成key和iv（初始化向量）
kdf = PBKDF2HMAC(
    algorithm=algorithms.AES(),
    length=32,
    salt=salt,
    iterations=100000,
    backend=default_backend()
)
key = kdf.derive(password)

# 加密函数
def encrypt(data):
    cipher = Cipher(algorithms.AES(key), modes.CBC(key[:16]), backend=default_backend())
    encryptor = cipher.encryptor()
    iv = key[16:]
    ciphertext = encryptor.update(data) + encryptor.finalize()
    return base64.b64encode(iv + ciphertext).decode('utf-8')

# 解密函数
def decrypt(encrypted_data):
    encrypted_data = base64.b64decode(encrypted_data)
    iv = encrypted_data[:16]
    ciphertext = encrypted_data[16:]
    cipher = Cipher(algorithms.AES(key), modes.CBC(iv), backend=default_backend())
    decryptor = cipher.decryptor()
    decrypted_data = decryptor.update(ciphertext) + decryptor.finalize()
    return decrypted_data

# 示例：加密字符串
plaintext = 'This is a secret message'
encrypted_text = encrypt(plaintext.encode('utf-8'))
print(f"Encrypted data: {encrypted_text}")

# 示例：解密字符串
decrypted_text = decrypt(encrypted_text)
print(f"Decrypted data: {decrypted_text.decode('utf-8')}")