Encryption method and device based on symmetric algorithm

The invention provides an encryption method and device based on a symmetric algorithm, and the method comprises the following steps: carrying out the first conversion of a plaintext key, and obtaining a white box key; carrying out second transformation on the S box of the symmetric algorithm to obtain a new encrypted S box SE', wherein the second transformation is reversible transformation of the first transformation; and carrying out standard symmetric encryption processing on a plaintext and the white box key based on the new encryption S box SE', and outputting a ciphertext to improve the security of the symmetric encryption algorithm, so that white box attack is resisted, and the security of the symmetric encryption algorithm is improved. 本发明提供了一种基于对称算法的加密方法及装置，所述方法包括如下步骤：对明文密钥进行第一变换，获取白盒密钥；对所述对称算法的S盒进行第二变换，获取新的加密S盒SE'，其中，所述第二变换为第一变换的可逆变换；基于所述新的加密S盒SE'对明文和所述白盒密钥进行标准对称加密处理，输出密文提高对称加密算法的安全性。借此，本发明实现了抵御白盒攻击，提高对称加密算法的安全性。