Encrypted File System For NAND Flash Based On JFFS2

As the range of application of embedded system is broader, it is more and more important toensure the security of sensitive data stored in it. Encrypted file system can be used to store sensitivedata into the underlying Flash device, which can achieve the purpose of protection of data. Nowmost of the storage device of embedded system is NAND Flash, but existing various encrypted filesystems are not designed for embedded system and fail to take physical characteristics of NANDFlash in account, which can’t work on embedded systems.Therefore, this paper puts forward anew encrypted file system named EJFFS for NAND Flash, which is based on JFFS2and can workdirectly on embedded System.EJFFS works on NAND Flash embedded system and is based on JFFS2journaling file systemand use the latest Linux encrypted file system named eCryptfs for reference. Therefore, this paperfirst introduces some knowledge of NAND Flash and embedded systems. Then this paper analyzesthe implementation algorithm of the main modules of JFFS2. Finally, this paper analyzes theimplementation mechanism of eCryptfs, including its key management mechanism, the encryptionmechanism and encrypted file formats. In the end, this paper puts forward the design of the newencrypted file system.Unlike other encrypted file systems, EJFFS takes the physical characteristics of embeddedsystem as well as NAND Flash into consider in its design, which can be directly used in variousNAND Flash embedded systems. At the same time, through the analysis of the test of EJFFS, theeffect of efficiency of reading and writing in NAND Flash is very small when data encryption isproceeding. Therefore, the encrypted file system has certain application significance.