AES加密的几种常用方式

pip install pycryptodome

• AES加密(utf-8字节处理)

from Crypto.Cipher import AES
from Crypto.Util.Padding import pad, unpad
import base64

# 明文和密钥都需要转为utf-8字节
key = b'1234567890abcdef'  # 16字节密钥
iv = b'abcdef1234567890'   # 16字节IV
plain_text = '你好，世界！'

# 填充明文到16字节倍数
plain_bytes = pad(plain_text.encode('utf-8'), AES.block_size)

# 创建AES加密器（CBC模式）
cipher = AES.new(key, AES.MODE_CBC, iv)
cipher_bytes = cipher.encrypt(plain_bytes)

# 可选：转base64方便存储/传输
cipher_b64 = base64.b64encode(cipher_bytes).decode('utf-8')
print('加密后(base64):', cipher_b64)

# 解密流程
cipher = AES.new(key, AES.MODE_CBC, iv)
decrypted = unpad(cipher.decrypt(base64.b64decode(cipher_b64)), AES.block_size)
print('解密后:', decrypted.decode('utf-8'))

• AES加密(utf-8字节处理，函数封装形式)

from Crypto.Cipher import AES
from Crypto.Util.Padding import pad

def aes_encrypt(data_string):
    key = "fd6b639dbcff0c2a1b03b389ec763c4b"
    iv = "77b07a672d57d64c"
    aes = AES.new(
        key=key.encode('utf-8'),
        mode=AES.MODE_CBC,
        iv=iv.encode('utf-8')
    )
    raw = pad(data_string.encode('utf-8'), 16)
    return aes.encrypt(raw)

# 使用示例
encrypted_bytes = aes_encrypt("Hello World!")
print('加密后(bytes):', encrypted_bytes)

与前面代码的区别：

1. 密钥/IV直接utf-8编码：key和iv直接用utf-8编码，不是十六进制转字节
2. 返回原始字节：直接返回加密后的字节，不做base64或hex编码
3. 函数封装：便于复用
4. 接口更简洁：只需传入明文字符串，返回加密字节
5. 适用场景不同：适合密钥/IV本身就是utf-8字符串的情况

• AES加密(十六进制字节处理)

from Crypto.Cipher import AES
from Crypto.Util.Padding import pad, unpad
import binascii

# 十六进制字符串转字节
key_hex = '1234567890abcdef1234567890abcdef'  # 32字符=16字节
iv_hex = 'abcdef1234567890abcdef1234567890'   # 32字符=16字节
plain_hex = '48656c6c6f20576f726c6421'         # "Hello World!"的十六进制

key = binascii.unhexlify(key_hex)
iv = binascii.unhexlify(iv_hex)
plain_bytes = binascii.unhexlify(plain_hex)

# 填充明文到16字节倍数
plain_padded = pad(plain_bytes, AES.block_size)

# 创建AES加密器（CBC模式）
cipher = AES.new(key, AES.MODE_CBC, iv)
cipher_bytes = cipher.encrypt(plain_padded)

# 转为十六进制字符串
cipher_hex = binascii.hexlify(cipher_bytes).decode('utf-8')
print('加密后(hex):', cipher_hex)

# 解密流程
cipher = AES.new(key, AES.MODE_CBC, iv)
decrypted = unpad(cipher.decrypt(binascii.unhexlify(cipher_hex)), AES.block_size)
print('解密后(hex):', binascii.hexlify(decrypted).decode('utf-8'))
print('解密后(text):', decrypted.decode('utf-8'))

• AES加密(函数封装形式)

from Crypto.Cipher import AES
from Crypto.Util.Padding import pad
import binascii

def aes_encrypt(data_string):
    key_string = "4E2918885FD98109869D14E0231A0BF4"
    key = binascii.a2b_hex(key_string)
    
    iv_string = "16B17E519DDD0CE5B79D7A63A4DD801C"
    iv = binascii.a2b_hex(iv_string)
    
    aes = AES.new(
        key=key,
        mode=AES.MODE_CBC,
        iv=iv
    )
    
    raw = pad(data_string.encode('utf-8'), 16)
    aes_bytes = aes.encrypt(raw)
    return binascii.b2a_hex(aes_bytes).decode().upper()

# 使用示例
encrypted = aes_encrypt("Hello World!")
print('加密结果:', encrypted)

与前面代码的区别：

1. 函数封装：将加密逻辑封装成函数，便于复用
2. API差异：使用 binascii.a2b_hex() 和 binascii.b2a_hex() 而非 unhexlify()/hexlify()
3. 输出格式：结果转大写，更符合某些系统要求
4. 固定密钥：密钥和IV硬编码在函数内，适合特定场景
5. 简化接口：只需传入明文字符串，返回加密后的十六进制字符串