Support encryption payload in uf2 file

[howard0su]

Is your feature request related to a problem? Please describe.
I would like to encrypt uf2 file with AES128/256 encryption method so that nobody is able to disassembly the file.

Describe the solution you'd like
Add code logic to support uf2 file with some extension flags which indicated the firmware is encrypted and need run decrypt before flash it.

[mickeydarrenlau]

Then where to put the keys

[ccrome]

Definitely something I'm interested in too.

for the i.MX RT family, there are two different encryption schemes depending on which member of the family -- BEE and OTFAD. Unfortunately at the moment, I don't know much more about it ;-)

[hathach]

Before discussing the implementation, I would suggest to bring this discussion to https://github.com/microsoft/uf2 for the author to make it into the specs first. E.g adding new flag for encrypted method/key etc..