SCADA file encryption method based on AES algorithm

The invention discloses an SCADA file encryption method based on an AES algorithm. The method includes the steps that S01, an improved AES encryption and decryption algorithm is achieved; S02, modules are selected according to file processing modes; S03, the length of a secret key K and the secret key are input; S04, an expansion secret key is generated; S05, an encryption/decryption file is established; S06, 16 bytes are taken out from the file waiting to be encrypted/decrypted, and the taken-out data are stored in an intermediate variable; S07, the data in the intermediate variable are encrypted/decrypted according to the length of the secrete key, and the encrypted/decrypted data are stored in the intermediate variable; S08, if the file waiting to be encrypted/decrypted is encrypted/decrypted, the file is closed, and the second step is executed, or else the sixth step is executed. According to the SCADA file encryption method, encryption and decryption linear attack resistance and differential attack resistance are improved, fewer hardware resources are occupied, and the method is particularly suitable for upgrading original equipment without modifying hardware design.