[Tutorial] Decrypt and modify MK7 files like KartParts_Param_Accel.bin

Discussion in '3DS - ROM Hacking, Translations and Utilities' started by Faewui, Jun 6, 2016.

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I speak english like a potatoes ?

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  2. a little...

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  4. You speak like an english

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  1. Faewui
    OP

    Faewui Newbie

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    Jun 6, 2016
    France
    Vers Paris
    Hey everyone ! I struggled to understand how the MK7 params files works. So I decided to make a tutorial for begginers :)

    What you will need:
    - a decrypted mk7 rom

    - Every File Explorer
    - an basic hex editor
    - anddd... A brain.

    So, let's starting !!

    1/ Let's extract KartParts_Param_Accel ( for example )

    Instructions


    2/ Let's open the file, and modify/decrypt it :D !

    Open your file with a hex editor, you will see something like that:

    Capture d’écran 2016-06-06 à 14.29.58.png

    You can see pointers ( Default, Lv1... etc,).

    The first 4 bytes (01 00 00 00) seem to be useless, but the bytes after ( 15000000 and 02000000 ) seem to be used.
    15000000 in hex converted to a signed int is "21".
    02000000 in hex converted to a signed int is "2".
    21 + 2 = 23.

    So we know that our file contain 23 values/pointers !!!


    We know that one pointer name is 32 bytes long ( use the brain... ),
    so we go count 32 * 23 AFTER the 12 first bytes, andddddddd,
    I remove this part because it's not the values, only the pointers and the file structure info. ( do not remove this part, it's only for the tutorial ! )

    Capture d’écran 2016-06-06 à 14.40.46.png

    So we know that there are 23 value... There is 46 "little packets"...

    46 / 23 = 2 !!!
    You're right !!! There is 2 "little packets" for each values.

    So it's better like that:
    Capture d’écran 2016-06-06 à 14.43.34.png
    Now, for example if I want to modify the value of "Default", we remember that "Default" is the first pointers, so we need to modify the first two packets !
    You can save your file and start being rich.

    3/Reinjecting the file into "common.szs"
    Instructions

    345678/End

    I'm new on this site, but I used it multiple times, so I decided to help a little.
    The only thing to say about me: I love everything that touch to the computers, skate and bear.

    If you know what is the name of the "little packets", you find some non-english words (im french), you can send me a pm ;).

    Good hacking ^^