[Yokowa]

rupor, I know the basic elctronics mainly analog circuits, not very familiar with embeded system boards, but I think I can handle some digital circuits.

This is my understanding of your idea:
Use the original update.img and update.img.sig from sony to pass the signature verification. when the script starts to mount update.img, the SD card emulator provides the update.img modified for jailbreak.

According to the script "linuxrc" from t3, the correct update.img.sig is generated from update.img by sha, rsa, aes-cbc, but in the flash packages(jailbreak.7z,resize.7z...) you made for t2, you use the same update.img.sig2 for different update.img, which confuses me a lot.

My questions is: where to get the original update.img and its update.img.sig that could pass the verification?