Decryption of Switch eShop titles: mark 2! by simonmkwii at 7:46 AM EDT on April 30, 2018
As I'm sure you're aware, there was a massive exploit that was discovered for Switch that allows you do basically anything.
You can now dump your NAND, and it is possible to extract tickets, which contain title keys, from saves in your NAND.
Game update tickets have the title key stored in plaintext, so I can retrieve those easily.
Unfortunately, game data and DLC tickets are encrypted with a console-unique RSA-2048 key.
Luckily, this key is easy to retrieve, but unfortunately, it's stored encrypted, and it requires an RSA_KEK (key encryption key, which is common, not console-unique) to decrypt the RSA key.
The KEK source is stored in the es system applet binary, but requires a GenerateAesKek() function to derive the actual KEK.
I have no idea how to do this, so if anyone knows about the Switch's cryptosystem, please help!
I have an insane number of games to rip, I bought over 200 Switch games from the eShop, so the sooner, the better!