The INCLUDE_UNIQUE_ID gate in handleGenerateKey (introduced as part of the
PR157 AOSP-compliance work) returns PERMISSION_DENIED when the caller
holds neither SELinux gen_unique_id nor REQUEST_UNIQUE_ID_ATTESTATION.
This breaks Google Wallet card binding on real devices: Wallet's
generateKey carries INCLUDE_UNIQUE_ID without holding the permission, so
its attestation key request is rejected and Wallet surfaces the failure
as "this phone does not meet the security requirements for Google
Wallet". Symptoms reported by users: clearing GMS data only helps for a
few seconds before the state regresses; no card can be added.
Naive removal of the gate is not safe: AttestationBuilder honours
`includeUniqueId == true` by computing an HMAC-SHA256 unique_id and
embedding it in the attestation extension. With the gate gone, GMS
attestation flows that include the tag end up with a unique_id in the
extension that Play Integrity flags as inconsistent for the caller,
turning all three integrity verdicts red.
The fix here splits the difference: when the permission check fails,
silently strip the INCLUDE_UNIQUE_ID tag from the KeyParameter array
(and re-parse `parsedParams`) instead of rejecting the request. The key
generates normally, AttestationBuilder takes the
`else { ByteArray(0) }` branch, and the resulting attestation simply
omits the unique_id field, matching pre-PR157 behaviour, where the
tag effectively had no effect.
Verified on a device that previously failed Wallet binding on the
PR157 baseline:
- Play Integrity: BASIC + DEVICE + STRONG all pass.
- Google Wallet: card binding completes successfully.
- Calls that DO hold the permission are unaffected (still emit
unique_id as before).
The rest of the PR157 compliance work (CALLER_NONCE handling,
AuthorizeCreate ordering, USAGE_COUNT_LIMIT counters, effectiveParams
merging) is preserved.