针对专用加密芯片进行DSP程序文件加密保护的成本高、需改变系统硬件架构、开发调试周期较长等现存问题，提出一种基于SM4密码算法的DSP程序文件加密保护方法。该方法是在DSP程序文件编译生成后，利用SM4密码算法对其进行加密处理，并将生成的密文程序文件存储于Flash中，只有在DSP上电运行时从Flash中读取该密文程序文件并结合匹配的密钥完成解密加载后才能正常运行。该方法以软件的方式实现了DSP程序文件的加密保护，可在不改变DSP硬件系统架构的情况下对DSP程序文件进行有效的加密保护，从而降低了硬件成本、提高了系统的安全性。
In view of the high cost, the need to change the system hardware architecture, and the long development and debugging cycle of DSP program file encryption with special encryption chip, this paper proposes a method of DSP program file encryption and protection based on SM4 encryption algorithm. In this method, after DSP program file is compiled and generated, SM4 cipher algorithm is used to encrypt it, and the generated ciphertext program file is stored in Flash. Only after DSP power on runs, the ciphertext program file is read from Flash and decrypted and loaded with the matching key, can it run normally. This method realizes the encryption and protection of DSP program files in the form of software, which can effectively encrypt and protect the program files loaded with DSP without changing the architecture of DSP hardware system, thus reducing the hardware cost and improving the security of the system.
