ROM Hack [POC] [Help needed] Need help making Custom roms for Sky3DS (proof of concept inside)

[Chelsea_Fantasy]

Hello, I have been recently working on making Custom roms for Sky3DS. I have made some results, but I still stucked on anothers.
I made my way to repack an official rom with a translation patch I am working on with some friends. Here's a video showing proof of it: (by the way, my gf's 3ds cart reader is almost broken --the contact metals got shortened-- so I have to put a post it note behind the sky3ds to make it work, do not blame me about it) (and about the bad video quality, my connection it's ultraslow, so I have to caonvert it in a very bad codec).


I was working on some other ideas, but got stucked on them at some point.
I was thinking on creating custom carts with homebrew (or converting eShop games to cart games), but they show some errors (same results for homebrew and eShop):
1-If I make the .3ds file from scratch they show invalid data and the template can not be generated
2-If I take an official rom, then replace the code in the exefs, the program does not launches on the 3ds, but the game shows up on the home menu (on Citra does not load when I decrypt the .3ds file)
3-If I take an official rom, then replace the code in the exefs and exheader, the cart does not appear in the home menu and shows "Unknown CTR Card" on DevMenu (on Citra the game/homebrew works fine if I decrypt the .3ds file)
of course, if I take an official rom and replace the exefs, exheader, ncsd header and ncch header, it will be like when I make the .3ds file from scratch.

My question is: Did anyone haves any hint to help me making these custom eShop-to-cart roms or custom homebrew roms?

Why is this important to the scene? ... well just think about a new homebrew entry point on 11.6 with a custom "homebrew launcher loader rom" on any 3ds system for these people with a Sky3DS.

By the way, all of this was tested on a Sky3DS with blue button.

 

[Sliter]

wow you are amazing! Great work!
They from Sky (?) must pay you for it! maybe even hire you ahhha nobody had a hope for doing a bit of it and now you come with this actually working at least for fan translation!

 

[Chelsea_Fantasy]

wow you are amazing! Great work!
They from Sky (?) must pay you for it! maybe even hire you ahhha nobody had a hope for doing a bit of it and now you come with this actually working at least for fan translation!

thanks pal , but it is really, not a big deal!

 

[samcambolt270]

impressive

 

[Pleng]

2-If I take an official rom, then replace the code in the exefs, the program does not launches on the 3ds, but the game shows up on the home menu (on Citra does not load when I decrypt the .3ds file)

I'm guessing that the header and actual game data are signed separately then? So the header shows up legit, but when you try to run it then the new code is unsigned so does not work. Don't think you're going to get much further than that, I'm afraid...

 

[Chelsea_Fantasy]

I'm guessing that the header and actual game data are signed separately then? So the header shows up legit, but when you try to run it then the new code is unsigned so does not work. Don't think you're going to get much further than that, I'm afraid...

I do not think it is an encryptiong and/or signature issue
I belive it is more a "flags issue"

 

[Pleng]

I don't know what a 'flags' issue is but what makes you believe that anything you've done so far should enable the 3DS to run unsigned code??

 

[Chelsea_Fantasy]

I don't know what a 'flags' issue is but what makes you believe that anything you've done so far should enable the 3DS to run unsigned code??

The code inside the ExeFS has no signature or encryption.
The ExeFS haves encryption, just like the ROMFS and as you can see on the video, it is decryptable and encryptable as well.

 

[Pleng]

The code inside the filesystem is not encrypted but the filesystem itself is? That doesn't make sense.

 

[Chelsea_Fantasy]

The code inside the filesystem is not encrypted but the filesystem itself is? That doesn't make sense.

Blame Nintendo, not me.
They encrypted the filesystem with a key stored on the 3DS hardware.

 

[Pleng]

If a filesystem is encrypted then everything within that filesystem ("the code") is also encrypted...

 

[Chelsea_Fantasy]

If a filesystem is encrypted then everything within that filesystem ("the code") is also encrypted...

yes and as I said, I can decrypt it and encrypt it at my free will
that's not the issue

 

[Pleng]

yes and as I said, I can decrypt it and encrypt it at my free will
that's not the issue

And can you sign it?

 

[Chelsea_Fantasy]

And can you sign it?

I will not continue your kid-like game, read my previous posts and you will find the answear

 

[Pleng]

It's a genuine enough question... So far nobody has been able to get a stock 3DS to run unsigned code. You believe that you can because.....?

 

[Chelsea_Fantasy]

It's a genuine enough question... So far nobody has been able to get a stock 3DS to run unsigned code. You believe that you can because.....?

The code inside the ExeFS has no signature or encryption.
The ExeFS haves encryption, just like the ROMFS and as you can see on the video, it is decryptable and encryptable as well.

 

[TheCyberQuake]

If it was possible we would have already been doing it. Its why we've always needed homebrew or signature patches to play romhacks. Otherwise other more talented devs would have already done this

 

[Clothahump]

wow you are amazing! Great work!
They from Sky (?) must pay you for it! maybe even hire you ahhha nobody had a hope for doing a bit of it and now you come with this actually working at least for fan translation!

I don't think this "discovery" is as revolutionary as it might seem to you. It's safe to assume that anyone with a little bit of knowledge of these things can tell / could have told you exactly what works and what doesn't (on a stock system).

So far nobody has been able to get a stock 3DS to run unsigned code.

That's just wrong. Userland homebrew does exactly that - run unsigned code on a stock console.

 

[Sonansune]

sky3ds can run unofficial rom with sig patch applied 3ds(basically 3ds that has cfw).

 

[Sliter]

I don't think this "discovery" is as revolutionary as it might seem to you. It's safe to assume that anyone with a little bit of knowledge of these things can tell / could have told you exactly what works and what doesn't (on a stock system).

right, but nobody sowed a modded rom running yet , if everyone could do, why haven't made already?
let me praise my pal XD