gmscompat: synthesize GSF package presence when GmsCore is installed - #432
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Alex9001 wants to merge 1 commit into
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gmscompat: synthesize GSF package presence when GmsCore is installed#432Alex9001 wants to merge 1 commit into
Alex9001 wants to merge 1 commit into
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Apps that probe com.google.android.gsf via PackageManager fail to enable FCM on fresh GrapheneOS installs where GSF is absent. When verified Play Services is visible to the caller, synthesize a minimal PackageInfo/ApplicationInfo for GSF so presence checks succeed. Real GSF installation remains blocked. Bug: GrapheneOS/os-issue-tracker#8567 Co-authored-by: Cursor <cursoragent@cursor.com>
Alex9001
marked this pull request as ready for review
August 21, 2026 15:24
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Summary
When
com.google.android.gsfis absent,ApplicationPackageManagerreturns a minimal syntheticPackageInfo/ApplicationInfofor GSF so third-party presence checks succeed — but only when verified Play Services (com.google.android.gms) is installed and visible to the caller. The synthetic object carries onlypackageName+enabled; no GmsCore signatures, version codes, or sharedUserId are copied. Real GSF installation remains blocked.Visibility-dependent gate
The GmsCore check goes through the normal PackageManager query, so it is subject to the caller's package visibility of
com.google.android.gms. That is intentional: an app that can see GmsCore is precisely an app where FCM is viable, so the shim engages exactly when the presence answer is useful — and never for apps that couldn't use FCM anyway. The gate also verifiesapplicationInfo.ext().getPackageId() == PackageId.GMS_CORE, rejecting lookalikes that lack the verified Google signing key.Motivation
GrapheneOS/os-issue-tracker#8567
Hikvision-family apps (Hik-Connect, Guarding Vision, HiLook, Annke Vision) gate FCM on a GSF package-presence probe; FCM itself works through GmsCore on GrapheneOS.
Non-goals
Test plan
Device tests require a GrapheneOS build/flash with this patch (not done yet):
Community APK workaround meanwhile: https://github.com/Alex9001/hikvision-grapheneos-fcm-patch