Homebrew Batch CIA 3DS Decryptor - A simple batch file to decrypt CIA & 3DS

[kevman323]

After messing with this, I found two things that will mess up this tool. If it won't decrypt a file for you, make sure it's not one of these things.

1. Strange characters will mess it up. I saw this elsewhere where somebody talked about the ! character messing things up, but any strange character, like Japanese text, etc. will cause issue. Examples I had were ! in multiple games, é in a pokemon game name, and the roman numerals Ⅳ used instead of IV in street Fighter for some reason.

2. The second issue is less clear, but it affects mostly DLC, and anything with a lot of NCCH files. Internally, in the batch script, it takes all NCCH files, and combines them into a variable for creating the cia. If there are too many files, the batch variable hits a hidden 8191 character limit, and the command fails because it is cut off.

Fixing this is out of my league, but as a workaround, rename the file temporarily to a one character name. If a file still has too many NCCH files, this may not work, but for me, this fixed conversion issues for all 4 of the files I had issues with by renaming them to "a.cia" temporarily.

Lastly, I still have one cia that is giving me issues, but it seems to be an issue with "decrypt.exe", and likely can't be fixed easily. Still, I hope this helps some of those with issues.

 

[Gee7220]

Hi, hoping someone can help me, I didn't find the solution in the comments... when I run the .bat file it doesn't decrypt the .3ds file I have in the folder. here is a copy of the log;

Parsing NCSD in file "Fire Emblem - Awakening (USA).3ds":
Parsing Main NCCH
Product code: CTR-P-AFEE
KeyY: 3B84AC414BC38A70533FC8BABD3E00BD
Title ID: 00040000000A0500
Format version: 2

ExHeader offset: 00000200
ExHeader counter: 00040000000a05000100000000000000
ExHeader size: 2048 bytes
ExeFS offset: 00000C00
ExeFS counter: 00040000000a05000200000000000000
ExeFS size: 2913792 bytes
RomFS offset: 002C9000
RomFS counter: 00040000000a05000300000000000000
RomFS size: 1119567872 bytes

Parsing Manual NCCH
Traceback (most recent call last):
File "decrypt.py", line 421, in <module>
File "decrypt.py", line 263, in parseNCSD
File "decrypt.py", line 278, in parseNCCH
File "decrypt.py", line 74, in __new__
ValueError: Buffer size too small (0 instead of at least 512 bytes)
Failed to execute script decrypt
[MAKEROM ERROR] Content 0 is corrupt

 

[hussammfj]

To anyone getting the 'running the batch goes directly to finish with no new file generated' - try dragging the CIA file to decrypt.exe (just clicking decrypt.exe does not work, you have to give it a file to chew on) and it should run through and generate a bunch on NCCH files. Then double click on the .bat and it will run through and generate a decrypted CIA/CCI.
Make sure everything is in the same folder.

i just signed up to the forums to say THANK YOU ARE, YOU ARE FUCKING AMAZING !!!...

 

[GLTTRPRNCS]

To anyone getting the 'running the batch goes directly to finish with no new file generated' - try dragging the CIA file to decrypt.exe (just clicking decrypt.exe does not work, you have to give it a file to chew on) and it should run through and generate a bunch on NCCH files. Then double click on the .bat and it will run through and generate a decrypted CIA/CCI.
Make sure everything is in the same folder.

Followed these steps, but the final CIA file it generated was still encrypted according to Citra. When i ran the batch file it did delete the NCCH files, but it still jumped straight to finish.

 

[FrutMose]

the program to decrypt doesn't run when I extract the zip

 

[UnfortunateLoaf]

Hi, I'm trying to decrypt a .3ds rom in order to turn it into a CIA from GodMode9, as if I tried directly gm9 gave a "Operation Falied" message, so then I decide to use this script and even after following @masterofphysics advice, I get no new file at all, I'm not sure if it's because the .3ds is from JPN region or some other locale problem. Any help would be greaatly appreciated, thanks.

 

[Kanay]

To anyone getting the 'running the batch goes directly to finish with no new file generated' - try dragging the CIA file to decrypt.exe (just clicking decrypt.exe does not work, you have to give it a file to chew on) and it should run through and generate a bunch on NCCH files. Then double click on the .bat and it will run through and generate a decrypted CIA/CCI.
Make sure everything is in the same folder.

Hello and excuse me, but it just deletes NCCH files and doesn't give anything back

 

[krek]

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