Homebrew 3ds extdata dump and restore tool (extra data editing!)

[MrCheeze]

https://github.com/MrCheeze/extdata_dump

Allows you to decrypt, edit, and then recrypt 3ds extra data. For use with Ninjhax.

Precompiled download: https://dl.dropboxusercontent.com/u/183608682/extdata_dump.zip

When run, you'll be presented with three options:

• Dump all extdata to sd card
• Dump extdata specified in config
• Restore extdata specified in config

I recommend just dumping all extdata to begin with, and browsing the dumps to see what you can find. There's a fair bit of documentation that might help you navigate the dumps over on the 3dbrew wiki.

If you want to restore an edited file (or just want to dump a single file instead of all of them), you'll have to edit config.txt. I've included a few examples in there that should make the format clear.

Finally, a technical note: the 3ds actually has three different types of extra data. Shared extdata is stored on the 3DS itself, and it usually relevant to multiple games (e.g. the Play Coin counter). "User" and "boss" extdata are both stored on the SD card, encrypted, and are associated with a specific game. Generally, Spotpass data goes into boss and everything else goes into user. This tool can access user and shared extdata, but boss extdata is likely impossible. This means it is not, for example, possible to dump or edit the Nintendo Video videos.

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edit from the future: hss2 has a modification that allows creating new directories, if your use case happens to require that.

 

[DarkFlare69]

Interesring... I'll look into this...

 

[TidusWulf]

hopefully not a dumb question. is this extdata located on the NAND partition?

I'm just confused why we would dump SD data since it's... you know... already on the SD card. :|

 

[MrCheeze]

hopefully not a dumb question. is this extdata located on the NAND partition?

I'm just confused why we would dump SD data since it's... you know... already on the SD card. :|

It's encrypted! With this you can actually read or modify it. Which is what things like the theme editor already do, but this is more general purpose.

Actually, shared extdata is stored on NAND, but there's not much in there besides playcoins and Miis.

 

[TidusWulf]

okay. cool. I'm trying to look at the wiki about what data is stored where, but it doesn't seem like it's much useful stuff (the themes and playcoins are great, but beyond that, I really can't say). Can this potentially dump data such as the streetpasses I've collected on Animal Crossing? if so, is it possible someone could eventually write a PC tool to edit the file to make a custom house full of whatever furniture they've been unable to track down so they can buy it from HHA? I'm aware that if you don't play ACNL, you won't have an answer for me, and that's okay.

 

[Naked_Snake]

how do we read the bin files?

 

[_eyCaRambA_]

Interesting, didn't think this would work with Ninjhax. So basically a partial SaveDataFiler for Ninjax. Cool, thanks!

 

[Agent Moose]

how do we read the bin files?

I'd assume through a Hex Editor.

 

[DarkFlare69]

It's encrypted! With this you can actually read or modify it. Which is what things like the theme editor already do, but this is more general purpose.

Actually, shared extdata is stored on NAND, but there's not much in there besides playcoins and Miis.

Miis are in there? Does this mean we could do some funky things to miis?

 

[Slushie3DS]

Miis are in there? Does this mean we could do some funky things to miis?

I wonder if we could modify the models/textures via our PC and push them back in.

 

[DarkFlare69]

I wonder if we could modify the models/textures via our PC and push them back in.

Exactly what I was wondering thinking. But if we did that, and then played in an ONLINE game where we used that Mii, would others see it changed?

 

[WateredFire19]

It's encrypted! With this you can actually read or modify it. Which is what things like the theme editor already do, but this is more general purpose.

Actually, shared extdata is stored on NAND, but there's not much in there besides playcoins and Miis.

What if we could edit our Mii's to have gold pants

 

[Slushie3DS]

Exactly what I was wondering thinking. But if we did that, and then played in an ONLINE game where we used that Mii, would others see it changed?

If it goes through another server, they should. The files may be pulled from out client, as they would have to always be checking to see if we've changed them. If they just pull the files into the server, then I think others could see it.

Edit: It's unlikely they do it like that, though.

 

[WateredFire19]

MrCheeze Could we possibly extract the .mii files, edit them to have Gold Pants with AJ's Mii editor, and then inject them using this tool?

 

[Slushie3DS]

Update to this since no one responded. I did it myself.

DarkFlare69, it's been done.

 

[WateredFire19]

DarkFlare69, it's been done.

How?

 

[Slushie3DS]

I'd image exactly how we were just talking, but may as well ask Huntereb.

 

[DarkFlare69]

I'd image exactly how we were just talking, but may as well ask Huntereb.

How to we extract the Miis?

 

[Slushie3DS]

How to we extract the Miis?

That part is what I'm unsure of. My cartridge should come in the next few days, and I will try it then.

 

[gudenau]

Making a play coin setter now.