ROM Hack [Request/Question]Can Decryption Be Done Without a 3DS?

[Ejoty]

I'll likely be Chastised or something of the sort for my general lack of knowledge, but I'm here anyways. I value my 3DSXL a lot, almost too much to HBrew or anything, but I plan on buying an N3DSXL Soon. I love Monster Hunter, and I've been infatuated with 4U, which is stored on my SD.

I wanted to do something with the weapon models for 4U ON MY COMPUTER ONLY. I wouldn't be texture editing or model replacing or anything, and putting it back on my 3DS in any way. I've been reading up on the whole decryption process, and I would need to do a lot of stuff with homebrew to get the XORPADs for the decryption, if I'm not mistaken. If there is no other alternative to get the XORPADs without a 3DS, How much risk would it be to Homebrew my 3DS and downgrade my Firmware to an appropriate version to do what I would need? Is this even possible when the game isnt a physical cartridge? Any and all help would be appreciated, but any and all chastising would be understood given my poor description of my needs and such. Thank you.

 

[cearp]

no, you (currently) need a hackable 3ds in the process, to decrypt keys, create xorpads etc
this is not a new question, have a little search next time, you might see other threads about this (maybe not, but worth a try)

 

[Asia81]

no, you (currently) need a hackable 3ds in the process, to decrypt keys, create xorpads etc
this is not a new question, have a little search next time, you might see other threads about this (maybe not, but worth a try)

""Is this even possible when the game isnt a physical cartridge?""
He have the game insstalled, so he can use braindump to dump the game (BD work on 10.3, but 10.5?)

 

[darklordrs]

A. People don't generally download encrypted CIAs; if you found it somewhere on the internet (cough that site with no name) it's probably decrypted already. Dumping full encrypted .cias requires 9.2 or less anyway, lmao. if you're talking just .cxis then you can just braindump, which doesn't require any risky homebrew at all and still gives you models and such

B. Risk is pretty up there when it comes to downgrading - like a 8% fail rate or some shit - but I've downgraded successfully, guided a friend through it successfully, and even just threw someone a basic bitch guide to downgrading and they got through it too. So long as you never screw anything up you can downgrade fine. Of course you can't downgrade if you're on 10.4+ tho so lmao lmao

 

[Ejoty]

""Is this even possible when the game isnt a physical cartridge?""
He have the game insstalled, so he can use braindump to dump the game (BD work on 10.3, but 10.5?)

I don't think My SD card would have enough space to dump the game, though I'm not sure how much space it could take up (I only have 1 GB Left, with a homebrew launcher and MH4U On the SD).

--------------------- MERGED ---------------------------

I guess the proper question would be what if the SD Card runs out of space while braindump is running?

 

[dubbz82]

I don't think My SD card would have enough space to dump the game, though I'm not sure how much space it could take up (I only have 1 GB Left, with a homebrew launcher and MH4U On the SD).

--------------------- MERGED ---------------------------

I guess the proper question would be what if the SD Card runs out of space while braindump is running?

I'm not familiar enough with braindump, but most reasonable programs should check to see that they have enough assets available to complete the operations requested. Option 2 would be to get a larger SD card?

 

[cearp]

""Is this even possible when the game isnt a physical cartridge?""
He have the game insstalled, so he can use braindump to dump the game (BD work on 10.3, but 10.5?)

i never used braindump, i'm not sure

 

[SciresM]

no, you (currently) need a hackable 3ds in the process, to decrypt keys, create xorpads etc
this is not a new question, have a little search next time, you might see other threads about this (maybe not, but worth a try)

This is actually not true.

Monster Hunter 4U uses 7.x encryption...and since the keyscrambler was broken you can decrypt the RomFS and .code exefs portions of it on a PC, same with any game that uses SEEDDB or New_3DS only Secure3+ encryption.

Spoiler: AES info for RomFS

(KeyX = slot_0x25 KeyX, KeyY = first 0x10 bytes from signature, CTR = Partition ID << 8 | (2 << 24))

It is true that exheader + exefs files not called ".code" can only be decrypted using the 3ds as a decryption slave, since we don't know slot 0x2C's KeyX.

If/when bootrom gets dumped, though, decryption will be completely doable on PC with no need for a 3ds console.

For this user's case, though? He can totally do decryption on PC.

 

[Ejoty]

This is actually not true.

Monster Hunter 4U uses 7.x encryption...and since the keyscrambler was broken you can decrypt the RomFS and .code exefs portions of it on a PC, same with any game that uses SEEDDB or New_3DS only Secure3+ encryption.

Spoiler: AES info for RomFS

(KeyX = slot_0x25 KeyX, KeyY = first 0x10 bytes from signature, CTR = Partition ID << 8 | (2 << 24))

It is true that exheader + exefs files not called ".code" can only be decrypted using the 3ds as a decryption slave, since we don't know slot 0x2C's KeyX.

If/when bootrom gets dumped, though, decryption will be completely doable on PC with no need for a 3ds console.

For this user's case, though? He can totally do decryption on PC.

This fills me with both hope and more questions than I had, but its a good start.

 

[cearp]

This is actually not true.

Monster Hunter 4U uses 7.x encryption...and since the keyscrambler was broken you can decrypt the RomFS and .code exefs portions of it on a PC, same with any game that uses SEEDDB or New_3DS only Secure3+ encryption.

Spoiler: AES info for RomFS

(KeyX = slot_0x25 KeyX, KeyY = first 0x10 bytes from signature, CTR = Partition ID << 8 | (2 << 24))

It is true that exheader + exefs files not called ".code" can only be decrypted using the 3ds as a decryption slave, since we don't know slot 0x2C's KeyX.

If/when bootrom gets dumped, though, decryption will be completely doable on PC with no need for a 3ds console.

For this user's case, though? He can totally do decryption on PC.

good news thanks