aes加密/解密代码

AES (Advanced Encryption Standard) 是一种常用的对称加密算法，它的全称是高级加密标准，常用于数据的安全传输。在Python中，我们可以使用`cryptography`库来实现AES加密和解密。下面是一个简单的示例：

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

def encrypt_AES(text, key, iv):
    backend = default_backend()
    cipher = Cipher(algorithms.AES(key), modes.CBC(iv), backend=backend)
    encryptor = cipher.encryptor()
    ciphertext = encryptor.update(text.encode('utf-8')) + encryptor.finalize()
    return ciphertext, iv

def decrypt_AES(ciphertext, key, iv):
    backend = default_backend()
    cipher = Cipher(algorithms.AES(key), modes.CBC(iv), backend=backend)
    decryptor = cipher.decryptor()
    decrypted_text = decryptor.update(ciphertext) + decryptor.finalize()
    return decrypted_text.decode('utf-8')

# 使用示例
key = b'sixteen_byte_key'  # 需要16字节长度的秘钥
iv = os.urandom(16)        # 需要16字节的初始化向量
plaintext = "Hello, AES!"
ciphertext, iv_used = encrypt_AES(plaintext, key, iv)
decrypted_text = decrypt_AES(ciphertext, key, iv_used)

print(f"Original Text: {plaintext}")
print(f"Ciphertext: {ciphertext.hex()}")
print(f"Decrypted Text: {decrypted_text}\n")