Squok writes referring us to several documents he’s found regarding hacking the bitstream in secure FPGAs:
In order to protect the intellectual property and to prevent fraud, e.g., by cloning an FPGA or manipulating its content, many current FPGAs employ a bitstream encryption feature, which is advertised by manufacturers as “making it virtually impossible for thieves to steal your design data”, like in the now-retired white paper WP261 from Xilinx… However, this assertion has been breached by researchers using “Power Analysis Attacks”.
Such attacks are outlined in these papers discussing bitstream decompilation and Extracting Keys from Xilinx Virtex-II FPGAs.
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