Hacking sky3ds, broken roms?

[hofotureas]

Hi,
i got a bunch of roms that dont work. i wonder if i could fix them to run.
an example, same game, different rom :

sha-256 of ncsd header
works:
210C5B1DB00D819C65D1F31A6603A42F30C3C66C6A2FBFD305F0C7F6F3F7A4CE5BA780524A33A84A...
broken:
4354522D502D425A4C50F31A6603A42F30C3C66C6A2FBFD305F0C7F6F3F7A4CE5BA780524A33A84A...

first bytes are off.
hex editr says:
works:
00000000 21 0C 5B 1D B0 0D 81 9C 65 D1 !.[.°..œeÑ
broken:
00000000 43 54 52 2D 50 2D 42 5A 4C 50 CTR-P-BZLP

conclusion:
on broken rom, first bytes are different than on working rom. but not random. they got replaced by serial of rom.
is this a common issue, will they run on other flashcards?


is it posible to extract the ncsd header and calc a new sha-256 ?

 

[Foxi4]

Hi,
i got a bunch of roms that dont work. i wonder if i could fix them to run.
an example, same game, different rom :

sha-256 of ncsd header
works:
210C5B1DB00D819C65D1F31A6603A42F30C3C66C6A2FBFD305F0C7F6F3F7A4CE5BA780524A33A84A...
broken:
4354522D502D425A4C50F31A6603A42F30C3C66C6A2FBFD305F0C7F6F3F7A4CE5BA780524A33A84A...

first bytes are off.
hex editr says:
works:
00000000 21 0C 5B 1D B0 0D 81 9C 65 D1 !.[.°..œeÑ
broken:
00000000 43 54 52 2D 50 2D 42 5A 4C 50 CTR-P-BZLP

conclusion:
on broken rom, first bytes are different than on working rom. but not random. they got replaced by serial of rom.
is this a common issue, will they run on other flashcards?


is it posible to extract the ncsd header and calc a new sha-256 ?

The ROM seems modified, but I can't verify that since I don't have it opened in front of me. If it is missing partitions like I assume, it'll never work. Sky3DS only runs with complete ROM's containing all the partitions, meaning they can be trimmed, but not Super-Trimmed. You can make correct templates with Sky Army Knife as long as the ROM's Unknown ID is within the Template. If you want to save space on your SD, your best bet regarding trimming is SAK's built-in trimmer which does not alter the ROM's structure and adds padding if it's required for the ROM to operate.