Hello
I am planning on using the Tivaware supplied boot loader to create a "secure" image upload to my device. For that purpose, I plan on using the BL_DECRYPT_FN_HOOK function which can be enabled in the boot loader configuration. I have two questions, which I cannot find answers to in the documentation:
1. Does the DFU interface specify any requirements to the sizes of the blocks transferred from the host to the device (e.g. is it a fixed block size, word aligned, etc...) ?
2. Does the boot loader support a method to abort the firmware upload in case the decryption of the image fails? I plan on using an authenticated encryption/decryption mode, with the authentication tag embedded in the image header. When the upload is completed and the tag does not match the expected tag, I would like to erase the image from flash (the image which has just been uploaded). Can this be done from within the decrypt call-back function, or does the boot loader support a better solution?
For the project I am currently using:
- TivaWare 2.1.0.12573
- Tm4c1233d5pm
- CCS v6
- TI v5.1.6 compiler
I appreciate any help you can provide.
Best regards
Christian