aes加密算法Python实现

AES（Advanced Encryption Standard）是一种对称密钥加密算法，它被广泛应用于数据保护领域。在Python中，我们可以使用`cryptography`库来实现AES加密。以下是一个简单的例子，展示了如何创建一个AES加密器和解密器：

from cryptography.hazmat.primitives.ciphers import Cipher, algorithms, modes
from cryptography.hazmat.backends import default_backend

def generate_key(key_size=16):
    return bytes.fromhex('0123456789abcdef'[i*2:i*2+2] for i in range(key_size // 2))

def pad_data(data, block_size=16):
    padding = block_size - len(data) % block_size
    return data + bytes([padding]) * padding

def encrypt(plaintext, key):
    backend = default_backend()
    cipher = Cipher(algorithms.AES(key), modes.ECB(), backend)
    encryptor = cipher.encryptor()
    padded_plaintext = pad_data(plaintext)
    ciphertext = encryptor.update(padded_plaintext) + encryptor.finalize()
    return ciphertext

def decrypt(ciphertext, key):
    backend = default_backend()
    cipher = Cipher(algorithms.AES(key), modes.ECB(), backend)
    decryptor = cipher.decryptor()
    padded_ciphertext = decryptor.update(ciphertext) + decryptor.finalize()
    unpadded_plaintext = padded_ciphertext[:len(padded_ciphertext) - padded_ciphertext[-1]]
    return unpadded_plaintext.decode()

# 使用示例
key = generate_key()
plaintext = "This is a secret message"
ciphertext = encrypt(plaintext.encode(), key)
print(f"Ciphertext: {ciphertext.hex()}")
decrypted_text = decrypt(ciphertext, key)
print(f"Decrypted Text: {decrypted_text}")