Encrypted MEMCARD1.DAT and 2? (PSX games)

melado · Post by **melado** » Thu Dec 28, 2006 9:59 am

Hi.

With all the PSX stuff on the PSP, everybody is re-taking their old games. Some even have saved games where continue from.

There are two files for each PSX game, called MEMCARD1.DAT and MEMCARD2.DAT, of 131120 bytes of size each, and with obvious content. They look like encrypted with a different key for each game and memory slot (even when all game slots are empty, file 1 and 2 are different).

I tried using a memory card file from ePSXe (131072 bytes), but it doesn't work, I get a 80000004 error.

So... I'm just a noob without much knowledge about this topic, and this is everything I could get. Now it's your turn ;)

Any ideas?

FreePlay · Post by **FreePlay** » Sat Dec 30, 2006 11:00 am

80000004 seems to be a catch-all error code for the POPS emulator, in my experience. I get the same error when I try to run it from my Undiluted Platinum chip.

I assume that the data is encrypted, probably in the same fashion as essentially all the other PSP savedata. Once we figure out the key for encryption (which must be stored somewhere in either the DATA.PSP of the EBOOT or in the firmware itself), decrypting and re-encrypting the POPS savedata should be no problem - assuming, of course, they haven't completely changed the way this is done.

adrahil · Post by **adrahil** » Sat Dec 30, 2006 7:00 pm

@melado: There now is CWCHEAT which accepts loading memory cards from epsxe :)

@FreePlay: It is plain old encryption :) It just seems that the key changes with the game.... I'm not sure though :s

melado · Post by **melado** » Sun Dec 31, 2006 1:42 am

adrahil wrote:@melado: There now is CWCHEAT which accepts loading memory cards from epsxe :)[

Oh! Could you give me more information about this? Any URL or something? Thanks!

Edit: okay, I found it by myself: http://www.maxconsole.net/?mode=news&newsid=13140 :)

niemand0815 · Post by **niemand0815** » Mon Jan 08, 2007 9:06 pm

i find the cwcheat solution to use savegames a bit complicated, also there are some games which have problems with it.

thus a method of encrypting and decrypting the memcards on the ms would be perfect if it can result in a gme->.dat converter for pops :-)

FreePlay · Post by **FreePlay** » Thu Jan 11, 2007 9:41 am

Well, there seems to be a universal encryption/decryption key stored in the POPS emulator, but all attempts thus far to actually use it seem to be failing. At the very least, the savedata encryption/decryption/utility samples in the SDK don't work.

adrahil · Post by **adrahil** » Thu Jan 11, 2007 9:44 am

Encryption/decryption is not only using chnnlsv, but also pipes all sceIo* commands thru a DRM-like filter, which decodes them/encodes them/does various things. (FYI The filter is installed in iofilemgr_dnas.prx, by the IoFileMgrForKernel_42F954D4 function, and modifies the output of some sceIo functions... I got the command figured out, but i'm too lazy to post it or even test it...)

weltall · Post by **weltall** » Sat Jan 13, 2007 8:31 am

niemand0815 wrote:i find the cwcheat solution to use savegames a bit complicated, also there are some games which have problems with it.

thus a method of encrypting and decrypting the memcards on the ms would be perfect if it can result in a gme->.dat converter for pops :-)

i don't see what's complicated it's more simple than copying a file to psp putting there the psp header loading it with an app which does the encryption and save closing it and loading your game and the inverse for the decrypting.
oh and forget doing it on a pc.

games doesn't have problems with cwcheat you just need to load saves earlier (keep select pressed while booting up and load when the menu appears) and all games reported as not working with certain saves didn't work even on epsxe

Alcahest · Post by **Alcahest** » Sat Jan 13, 2007 10:45 am

I agree with the above, the cwcheat function couldn't be easier to use and worked flawlessly on every attempt in here; kudos welt ;)
Later,

Alcahest