I can you say why I not plan to do that. I simply know not enough about filesystems. Is the de/encryption a prob? No, its the easiest part on the prog. Its easy to write a fuction for on-the-fly encryption, simply a invers of my read_device(). I have no wish to write a app was kill in worst case a many ps3-hdd's. Only because i forget to set a flag or to update a special value in superblock or cylinder. And why write such a prog? There is always a better way. Linux.
glevand has it show (on psdevwiki.com/ps3/Mounting_HDD_on_PC). It is easy to mount a ps3 hdd on linux.
He show it for a slim hdd, ok, but for a fat only the decryption is other.
For slim: cryptsetup create -c aes-xts-plain64 -d <key-file> -s 256 <decypted device name> <path to mapped encrypt device>
For fat: cryptsetup create -c aes-cbc-null -d <key-file> -s 192 <decypted device name> <path to mapped encrypt device>
Next is, compile the kernel for UFS write support, and mount gameOS rw.
Work perfect for me. So why a maybe risky hombrew, if i can use a brilliant OS with proper coded device driver.
yes, but only if you have the eid_root_key from the dead ps3. Brenza about the write feature, here is what 3141card answered: