Python sm4加解密

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安装模块gmssl，pip install gmssl

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import binascii
from gmssl import sm3, sm4

# sm3摘要算法实现
def sm3_digest(data):
    if type(data) is str:
        byte_array_data = bytearray(data.encode('utf-8'))
    elif type(data) is bytes:
        byte_array_data = bytearray(data)
    elif type(data) is bytearray:
        byte_array_data = data
    else:
        logging.info('sm3 digest input error')
        return
    return sm3.sm3_hash(byte_array_data)


# SM4加密模块
class SM4:
    def __init__(self):
        self.crypt_sm4 = sm4.CryptSM4()

    @staticmethod
    def str_to_hex_str(hex_str):
        """
        字符串转hex
        :param hex_str: 字符串
        :return: hex
        """
        hex_data = hex_str.encode('utf-8')
        str_bin = binascii.unhexlify(hex_data)
        return str_bin.decode('utf-8')

    def encrypt_sm4(self, encrypt_key: str, value: str, mode: str="ECB", iv: str=None):
        """
        sm4加密
        :param encrypt_key: sm4加密key
        :param value: 待加密的字符串
        :param mode: 模式，CBC or ECB
        :param iv: 偏移量（ECB模式没有偏移量）
        :return: sm4加密后的十六进制值
        """
        crypt_sm4 = self.crypt_sm4
        crypt_sm4.set_key(encrypt_key.encode('utf-8'), sm4.SM4_ENCRYPT)  # 设置密钥
        bytes_data = value.encode('utf-8')
        if mode == "ECB":
            encrypt_value = crypt_sm4.crypt_ecb(bytes_data)
        else:
            assert iv, 'CBC mode must set iv'
            encrypt_value = crypt_sm4.crypt_cbc(iv.encode('utf-8'), bytes_data)
        return encrypt_value.hex()

    def decrypt_sm4(self, decrypt_key: str, encrypt_value: str, mode: str="ECB", iv: str=None):
        """
        sm4解密
        :param decrypt_key:sm4加密key
        :param encrypt_value: 待解密的十六进制值
        :param mode: 模式，CBC or ECB
        :param iv: 偏移量（ECB模式没有偏移量）
        :return: 原字符串
        """
        crypt_sm4 = self.crypt_sm4
        crypt_sm4.set_key(decrypt_key.encode('utf-8'), sm4.SM4_DECRYPT)
        if mode == 'ECB':
            decrypt_value = crypt_sm4.crypt_ecb(bytes.fromhex(encrypt_value))
        else:
            assert iv, 'CBC mode must set iv'
            decrypt_value = crypt_sm4.crypt_cbc(iv.encode('utf-8'), bytes.fromhex(encrypt_value))
        return decrypt_value.decode('utf-8')

    
if __name__ == '__main__':
    app_key = "12345678901234561234567890123456"
    strData = "90897h8789thvht"
    iv = '1234567891234567'
    SM4 = SM4()
    print("原字符：", strData)
    encData = SM4.encrypt_sm4(app_key, strData, mode='CBC', iv=iv)  # 加密后的数据
    print("sm4加密结果：", encData)

    decData = SM4.decrypt_sm4(app_key, encData, mode='CBC', iv=iv)
    print("sm4解密结果：", decData)  # 解密后的数据