How to detect save file modification?

Discussion in 'RPG Maker MV' started by Akuri78, Nov 28, 2018.

  1. Akuri78

    Akuri78 Warper Member

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    I've downloaded this Enigma Virtual Box software, to make all of my game data that I exported from RPG MAKER MV into one giant "game.exe" file.

    So now the players can't mess around with the games ressources like the js or json files.

    The problem now is, if the user want's to save they're game. I had to create an folder called "save". So now the user can access the RPG MAKER MV save files upload them to an site, decrypt it and change all the value of gold, mana etc. They then download the new edited file and replace it with the old save file. Now they have unlimited gold or mana etc...

    How do I solve this problem? Is there any better encryption to save files? Or is there any plugin to save this kinda problem?
     
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  2. Zeriab

    Zeriab Huggins! Veteran

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    Is it truly a problem that needs solving?

    That said, create some hash values and store them along the save. Upon read check if the hash values are as expected, otherwise discard the save. Remember to sprinkle the hash values with some salt ^^
     
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  3. Akuri78

    Akuri78 Warper Member

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    That's a good idea, but how do I access the save file? How do I write into an save file?
     
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  4. Andar

    Andar Veteran Veteran

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    you need to rewrite the save and load functions inside your game, and that requires programming knowledge.

    Basically this is almost never done for a lot of reasons - you basically have to rewrite the save function in a way that stores a checksum of the save with it, and then rewrite the load function so that it loads the checksum in addition to the savedata and compares it.

    And the result is that the people who really want to edit savegames still can do that, because there are cheat engines out there that take even such security into account - it just means that the first person to try to edit the savegame needs to invest another hour of work to find the checksum.
     
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  5. Poryg

    Poryg Pixie of the Emvee kingdom, Ham of a Hamster Veteran

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    I would say, challenge accepted, because it took me about 10 seconds to find an enigma virtual box unpacker.

    Anyway, if you're worried about the saves, just editing the makeSaveContents will take out most savefile editors on the web. However, I can still mess with the game in the memory, there are countless tutorials on using cheat engine to alter rpg maker games' values for gold etc.
     
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  6. Akuri78

    Akuri78 Warper Member

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    Yeah you are right guys.. if they wanna change the data, they should do it. Thank you for your help and advices.
     
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