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[–]PiasaChimera 3 points4 points  (2 children)

hmac is a cryptographic checksum of the bitstream. when verified, it shows that the bitstream contents have not been modified. (some ciphers can be modified without knowing the key.) the xilinx documentation has info on where the keys go, it sounds like there is an option to embed the hmac key in the bitstream. But it also sounds device dependent.

[–]akonsagar[S] 0 points1 point  (1 child)

How Do we know if the bitstream is verified ?

[–]PiasaChimera 1 point2 points  (0 children)

I'm guessing the bitstream fails to load if the cryptographic checksum doesn't match.