XAPP1309 (v1.0) March 7, 2017
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Summary
The secure boot functionality for the Zynq®-7000 All Programmable (AP) SoC provides the
capability to authenticate all partitions loaded at boot using RSA-2048 authentication. It also
supports advanced encryption standard (AES) encryption of partitions that need confidentiality.
The Zynq-7000 AP SoC immutable BootROM includes security functions to provide a hardware
root of trust (HROT) to protect against early load attacks.
This application note discusses a method to add measured boot capability to Zynq-7000 AP
SoCs used in a connected environment. A server provides remote attestation that the
embedded systems boot with trusted software over a secure network. The method uses a
trusted platform module (TPM) to enhance the HROT functionality. The TPM provides
cryptographic functions in a cost-effective, tamper-resistant device which are an effective
complement to Zynq-7000 SoC security functions.
Download the
reference design files
for this application note from the Xilinx website.
Introduction
In most current applications, Xilinx FPGAs and SoCs are programmed once at the factory and
often not reconfigured for the life cycle of the device. A method to add functionality and/or
reduce the total cost of ownership (TCO) of an embedded system is to support field updates. In
Zynq-7000 AP SoCs, the SoC and programmable logic can be updated, so field updates can be
very effective. Field updates are typically done over the Internet, which opens up attacks on an
embedded system to anyone with network access. Measured boot and network security are
critical in firmware updates.
Figure 1
shows an example system environment that uses measured boot. A server manages
the software load, update, and validation of fielded, embedded systems based on the
Zynq-7000 AP SoC. The embedded systems connect to the server using Ethernet. In addition to
updating software on the embedded systems, the server verifies that the correct, trusted
software is loaded. This verification by the server, done at boot and run time, is remote
attestation.
Application Note: Zynq-7000 AP SoC
XAPP1309 (v1.0) March 7, 2017
Measured Boot of Zynq-7000 All
Programmable SoCs
Author: Lester Sanders