(adsbygoogle = window.adsbygoogle || []).push({}); When I looked at this board and various other sites for the release of Campaign / Spec-Ops hacks for MW2, I've found out that there's none, only the 360 version exists.
So, I've begun my journey on trying to get it working for the PS3 version. And in the end, I've finally got it working... damn that took me a while to understand exactly how everything work.

I have successfully re-summed SAVEGAME.SVG and loaded da shit up in the game without any problem.

I'm not going to release the full working hack any time soon, but I'll release the half working hack for now (the download link is below) since the DVARs are already in public domain.

This half-working hack includes infinite health, super jump and speed and infinite ammo (just like what the 360 version includes) :

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I'll try to make this short, ok, here goes.

Try to load the save in MW2, and you'll get this error:



MW2 save is checksummed, just like other games' saves. If there's no copy protection on them, they are likely to be checksummed.

When you save data in-game, PS3 takes every single byte of a save data (e.g. SAVEGAME.SVG) and re-generate a checksum. So, if you change something inside SAVEGAME.SVG and try to load it in-game, PS3 will compare this editted SAVEGAME.SVG and the checksum value. If this SAVEGAME.SVG and the checksum value are not the same, you'll get a 'bad checksum' error. Understand?

Here's more information about checksum:
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Good thing is that the checksum is stored inside SAVEGAME.SVG, not inside the PS3 system!

All you need to do is to locate this checksum in SAVEGAME.SVG and update it. In other words, you need to identify how SAVEGAME.SVG is checksummed and then you need to know what data is covered by that function before you can do anything about it.

I'll give you a few hints regarding the checksum:

- Get a lot of SAVES that are almost the same (same mission, same checkpoint but different difficulty) and compare to each other in any hex editor program.

See which bits always change and see which bits don't change. There's a good chance that the bits that always change are the checksum.

- To update the checksum value, you must generate a new checksum and replace that with the old checksum value somewhere inside the save ...

- If you think you have found where the checksum is, you must ignore that bit and then generate a new checksum based on everything else (data), anything that's not part of the checksum.

- If you see 4 bytes (8 digits) that always change, it's likely not to be MD5 or something similar. If you didn't know, a MD5 hash has 32 digits.

So, if you generate a checksum that happens to be the same as the checksum inside SAVEGAME.SVG (un-hacked), you're set!!

If you have never done this before. I suggest following these tuts, it will make you understand the whole thing easier:

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And

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If you have followed these tuts and got the matched results, then fixing MW2's checksum will be easy.

Anyway, if you have managed to re-sign the save correctly, you can get more hacks. The full list of DVARs is available:

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Just add desired DVARs with thier values (e.g. ..200B0..) under compress_$mapname inside the save and you're set.

Enjoy and good luck.

Post the save with the right checksum?

Boojak can you please post the file somewhere elese the file has no more room for free users (meaning too many fckers downloaded it and i can't download it anymore)

i still don't believe it.. before i'll se a photo og a video

where do you set the DVARs??? and when you have the perfect match with the checksum where do you put it???

If the checksum is CRC32, then it's probably at 0x14-0x17. But trying to find out which part of the file is used to generate the checksum is driving me crazy.

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If anyone else has any ideas? I've been making tons of selections from after what I assume is the checksum, but so far nothing matches.

You didn't read my first post... In it, I mentioned that I added the DVARs after compress_$mapname in the file.



Sigh, you don't get it. I'll think of an example to make you understand:

1) You save data after finishing a mission or two.
1) PS3 inspects this brown box (SAVEGAME.SVG) with information (information such as data, file size, etc) inside.
2) You tag this brown box with a number (checksum) BASED on the information inside. That number is 1234.
This brown box has the '1234' tag on the top of the box. This checksum (e.g. 1234) is INSIDE the file. In other words, if you view SAVEGAME.SVG in hex editor, the '1234' thing will be there.
3) You wake up tomorrow, and you hop on MW2 and re-load the save.
4) PS3 checks if the information inside that brown box is correct for the tag (checksum).
5) Save successfully reloaded...

To change information inside that brown box and load, you MUST update the tag (checksum) on the brown box, otherwise it won't work.

You've just answered yourself. If you generate a checksum that's matched the orginal checksum, it means that you know where is this checksum (inside the file). So, knowing that you have found the checksum, start adding DVARs, generate a new checksum and then replace that new checksum with the orginal checksum inside the file..



Well done, you're getting there.

I'm suprised none of you have googled my username (Boojak)...

I posted this thread on a different forum days before I got it working. Pay very attention to my post and the replies and you will get something.

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the word "compress" is no where in the savegame.svg

You said that the PS3 checks the .svg file to see if the hash matches. Well, if you rehash and change the hash in the file, then the PS3 would read it as corrupted since you didn't change the information that needs to be compared.

Also, I noticed the same thing as bmh54321.