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A remote cryptographically-signed attestation is not reproducible https://developer.android.com/training/safetynet/attestation https://developer.android.com/tr

• deleted 5y ago
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• rstuart4133 5y ago
  > A remote cryptographically-signed attestation is not reproducible No one wants to reproduce an attestation. If you could, it could be copied, and if you can copy an attestation any hardware could send it to prove it was something else - something the other end trusts, rendering is useless for it's intended purpose. However, the attestation is attesting the hardware you are running on is indeed "reproduced", as in it is a reliable copy of something the other end trusts. It could be a device from Yubi Key and in effect you are trusting Yubi Corp's word on the matter. Or, it could be an open source design everybody can inspect, reproducibly rendered in hardware and firmware. Personally, I think trusting the former is madness, as is trusting the latter without a reproducible build.
• pabs3 5y ago
  I don't know much about attestation, but the repro builds folks have an approach for dealing with signatures; you build once, then copy the signature into the source, so that as long as the unsigned build result is bit-identical, the signatures still match and anyone can reproduce the signed build result. https://reproducible-builds.org/docs/embedded-signatures/ https://reproducible-builds.org/docs/embedded-signatures/