摘要
In a security-aware multi-chip IC, each constituent die needs to be equipped with an ID before being integrated into the common IC substrate. Since it is not easy to probe a bare die through the tiny micro-bumped IOs, a general and scalable scheme is needed so the final assembled multi-die IC can perform the authentication process easily - i.e., checking for the presence of unauthorized dice. In this paper, we propose such an "authentication scheme" using a scalable hash-chain structure. In our scheme, one die is designated as the Master die while the others are Client dice. The Master die is inserted with a so-called AU-Center, while each of the Client dice is inserted with an AU-Controller. The AU-Center and all the AU-Controllers are connected in a daisy-chain structure to facilitate the collection and hashing process of all die IDs. At the end of the authentication process, a final signature is produced. Comparing the final signature with the pre-recoded golden signature can reveal if there is any unauthorized die assembled in the multi-die IC. It is notable that in our scheme all the die IDs remain secretive since they are not revealed on the die-to-die interconnecting wires at all. We have implemented this scheme in an FPGA chip to demonstrate its feasibility and its ability to detect unauthorized dice.