generateKey synthesized device-property attestation unconditionally:
the BRAND/DEVICE/PRODUCT/MANUFACTURER/MODEL tags that
setDevicePropertiesAttestationIncluded emits. A forged key thus
succeeded where real silicon returns CANNOT_ATTEST_IDS. Hardware that
never provisioned device IDs cannot attest them, so forging them is an
over-capability tell: a genuine device of the same class fails the
identical request.
Add DeviceAttestationService.canAttestDeviceIds, a lazy probe that asks
the real TEE to attest device properties once and caches the verdict.
It is gated behind isTeeFunctional, so a silent or dead TEE
short-circuits to "cannot attest" without a second doomed probe.
handleGenerateKey now returns KEYMINT_CANNOT_ATTEST_IDS for any
device-ID or device-property attestation the real TEE cannot satisfy,
uniformly across AUTO, PATCH, and GENERATE. Basic attestation carries
none of these tags and is untouched.
Verified on 23106RN0DA: kknd under GENERATE now WARNs, matching a stock
locked-bootloader device. Principle: forge health, mirror capability.
Enginex0
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