Advertising (This ad goes away for registered users. You can Login or Register)

pfsSKKey and PS Vita game saves

HENkaku is a native Homebrew Enabler for the PS Vita and PS TV. It lets you run homebrews on the PS Vita
Post Reply
lorak
Posts: 56
Joined: Tue Aug 30, 2011 12:00 am

pfsSKKey and PS Vita game saves

Post by lorak »

As we all know, finally we can decrypt/encrypt our (Q)CMA-generated PS Vita backups (including game saves) with psvimgtools only with a computer. Many thanks to xyz, Proxima, plutoo and Yifan Lu by the way.

I just decrypted a savegame from MLB 14 The Show PS Vita version with psvimgtools and I noticed that all my game saves from this game are still encrypted. I also have a sealedkey file inside sce_sys folder after extraction. I guess that the sealedkey file contains the pfsSKKey key to actually decrypt the game saves, similar as with PS4.

Could someone please guide me how to use the pfsSKKey to decrypt all my game saves at this 2nd level?
:?:
Thank you.
Advertising
CPUzX
Moderator
Posts: 276
Joined: Thu Nov 28, 2013 8:25 pm
Location: United Kingdom

Re: pfsSKKey and PS Vita game saves

Post by CPUzX »

Some games like Metal Gear Solid HD Collection have secondary save encryption in the form of another unique checksum that is only in place for that specific game. pfsSKKey probably did everything right, but there might be another specific checksum for certain games.

I've never used pfsSKKey though, so I maybe wrong, but just thought I'd clarify this.
Advertising
lorak
Posts: 56
Joined: Tue Aug 30, 2011 12:00 am

Re: pfsSKKey and PS Vita game saves

Post by lorak »

CPUzX wrote:Some games like Metal Gear Solid HD Collection have secondary save encryption in the form of another unique checksum that is only in place for that specific game. pfsSKKey probably did everything right, but there might be another specific checksum for certain games.

I've never used pfsSKKey though, so I maybe wrong, but just thought I'd clarify this.
Ok.
By the way, all my game saves from MLB 14 The Show have two files in the correspondent folder after extraction with psvimgtools: DATA_00.BIN and CRC.BIN. However, this CRC.BIN file looks encrypted to me as well (as DATA_00.BIN) and its size is 32 KB. In this situation I do not even know what is the CRC value to compare the checksum from DATA_00.BIN.

On the other hand, the same game save decrypted with Vita savemanager shows a 4 byte number in CRC.BIN (1KB size) and it is equal (after inverting positions) to the checksum (CRC-32) of DATA_00.BIN calculated in an hex editor.

How to decrypt these kind of game saves either by means of CRC (checksum) or pfsSKKey?

As far as I know checksums detect file modifications comparing the checksum of a file with a value the system knows where to find. If I am missing something here could you please clarify?
CelesteBlue
Posts: 50
Joined: Fri Aug 05, 2016 9:19 pm

Re: pfsSKKey and PS Vita game saves

Post by CelesteBlue »

You can't decrypt PFS encrypted files by yourself.
Vita on <=3.60 can achieve that by some tricks...
The reason why we can't decrypt it, even knowing the pfsSKKey, is that we don't know PFS decryption algorithm.
Post Reply

Return to “HENkaku”