A great way to contribute to the GrapheneOS projects is installing Auditor on a device that's not already supported (see attestation.app/about#device-s) and submitting sample data from it. See attestation.app/tutorial for instructions on installing the app and expanding device support.
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Once a valid sample is submitting from a device running the stock OS with a locked bootloader, it quickly becomes supported by Auditor and AttestationServer. The samples are also useful as a basic device survey for other purposes like determining potential targets for GrapheneOS.
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A subset of the sample data which has passed verification is published at github.com/GrapheneOS/Att. It includes the public key certificate chain for both sample TEE and StrongBox keys (which have passed verification and are with stock OS + locked bootloader) and some system props.
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