I have been researching diffrent ways to make FAT16 more secure.

FAT16 is the most simple file system I have seen. But it is very insecure.
even if you were to implement a multi-user system with privlage rights someone could use a DOS boot disk to boot the computer and access the files.

We need something that would protect the files agenst such.
Maby using encryption. I thaught about modifying the FAT16 Directory structure to implement security.

Any thaughts would be appreciated.

Thanks.

The best way for protection is to implement it at the hardware level; you could have some access code necessary to access to the drive, and if someone tried to open the case, it would destroy the platters. Just a thought.

There is a method. You can create invisible descriptors with additional info in it (privileges, rights, etc) but it will work only in your OS. These descriptors will be invisible in MS-DOS.

Geek,
i think encrypt your files that you dont want others to open.
and back them up on cd.

The theme is about FAT16 in self-made OSes, right? So, we need to talk about making it more secure, not about other ways to hide our files. If somebody asked it, he needs it, right?

I think the only way is to encrypt the files. If you change the structure of FAT16, than it's not longer FAT16 and other OSs won't be able to use the files. So you can implement a buildinencrypter and -decrypter in your driver. Other OSs will be able to read the files, but only the encrypted. So they'll have to decrypt.

Nope, they will be able to use these files. Do you know how WIN32 makes long names? And MS-DOS still works with those files. The same way to include privelege info for your os.

Except that it will only be secure under your OS. If I come in with a DOS or Linux boot disk, I can still view/modify/copy any files on your modified FAT16.

I'd say to go with transparent encryption when saving data. You could then use it over an unmodifed FAT16 disk, and it'd be more secure than adding additional descriptors to the file system.

yo
my point was with the file encription, that you cannot make files/data secure encrypting the directory structure and or the fat,
files are on the disk raw mode,
anyone can access them
you can only make secured data storage if you encrypt the whole drive.

and use encryption that cannot be decrypted without the code you use, otherwise who disassembles your code can get the decode algorhithm and finally decrypt files.

@NR: Right, I thougt about saving the files from anyone not only your OS...

Yep, just as i said... Because, ext2, for example, more secured FS, but again - only under Linux, for example. Ntfs - the same. So i thought about making FAT as secured as ext2. Encryption is method for ANY fs, not only FAT(but we're talking about it... so).

For the ultimate in security, use encrypted files and a steganographic file system like StegFS: http://www.mcdonald.org.uk/StegFS/

Why would you want to make FAT16 more secure? By modifying FAT16, it is no longer FAT16, but a whole new FileSystem. Which isn't a bad idea, BTW, since FAT16 is obsolete anyways. Make a new FS or use an existing one, I don't think FAT16 is secure and I don't think you can make it secure.