treble_evolution/patches/platform_frameworks_base/0050-Allow-signature-spoofing-for-microG-Companion-Servic.patch

From 3ca9e6601b43308aa1159b08e4c67e4163011c7f Mon Sep 17 00:00:00 2001
From: LuK1337 <priv.luk@gmail.com>
Date: Mon, 19 Feb 2024 16:20:04 +0100
Subject: [PATCH 50/51] Allow signature spoofing for microG Companion/Services

This patch enables signature spoofing when the following conditions are
met:
* Build is debuggable (userdebug/eng)
* Package name is com.android.vending or com.google.android.gms
* Package is signed with microG release keys
* Fake signature is correct

Additionally, we let these apps be forceQueryable if they so desire.

phh change: No need to be debuggable

Change-Id: I8fc82ed266a2cc59636b662c7ea7e29c94f509b5
---
 .../com/android/server/pm/AppsFilterImpl.java |  2 +
 .../com/android/server/pm/ComputerEngine.java | 46 +++++++++++++++++++
 2 files changed, 48 insertions(+)

diff --git a/services/core/java/com/android/server/pm/AppsFilterImpl.java b/services/core/java/com/android/server/pm/AppsFilterImpl.java
index 82622d9a4ea8..277c9abe2e1c 100644
--- a/services/core/java/com/android/server/pm/AppsFilterImpl.java
+++ b/services/core/java/com/android/server/pm/AppsFilterImpl.java
@@ -36,6 +36,7 @@ import static com.android.server.pm.AppsFilterUtils.canQueryAsUpdateOwner;
 import static com.android.server.pm.AppsFilterUtils.canQueryViaComponents;
 import static com.android.server.pm.AppsFilterUtils.canQueryViaPackage;
 import static com.android.server.pm.AppsFilterUtils.canQueryViaUsesLibrary;
+import static com.android.server.pm.ComputerEngine.isMicrogSigned;
 
 import android.annotation.NonNull;
 import android.annotation.Nullable;
@@ -599,6 +600,7 @@ public final class AppsFilterImpl extends AppsFilterLocked implements Watchable,
             newIsForceQueryable = mForceQueryable.contains(newPkgSetting.getAppId())
                             /* shared user that is already force queryable */
                             || newPkgSetting.isForceQueryableOverride() /* adb override */
+                            || (newPkg.isForceQueryable() && isMicrogSigned(newPkg))
                             || (newPkgSetting.isSystem() && (mSystemAppsQueryable
                             || newPkg.isForceQueryable()
                             || ArrayUtils.contains(mForceQueryableByDevicePackageNames,
diff --git a/services/core/java/com/android/server/pm/ComputerEngine.java b/services/core/java/com/android/server/pm/ComputerEngine.java
index 3cb2420cd223..b0d9be30edc1 100644
--- a/services/core/java/com/android/server/pm/ComputerEngine.java
+++ b/services/core/java/com/android/server/pm/ComputerEngine.java
@@ -100,6 +100,7 @@ import android.content.pm.UserPackage;
 import android.content.pm.VersionedPackage;
 import android.os.Binder;
 import android.os.Build;
+import android.os.Bundle;
 import android.os.IBinder;
 import android.os.ParcelableException;
 import android.os.PatternMatcher;
@@ -172,6 +173,7 @@ import java.util.Collections;
 import java.util.Comparator;
 import java.util.List;
 import java.util.Objects;
+import java.util.Optional;
 import java.util.Set;
 import java.util.UUID;
 
@@ -421,6 +423,10 @@ public class ComputerEngine implements Computer {
     private final PackageManagerInternal.ExternalSourcesPolicy mExternalSourcesPolicy;
     private final CrossProfileIntentResolverEngine mCrossProfileIntentResolverEngine;
 
+    // Signatures used by microG
+    private static final Signature MICROG_FAKE_SIGNATURE = new Signature("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");
+    private static final Signature MICROG_REAL_SIGNATURE = new Signature("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");
+
     // PackageManagerService attributes that are primitives are referenced through the
     // pms object directly.  Primitives are the only attributes so referenced.
     protected final PackageManagerService mService;
@@ -1463,6 +1469,42 @@ public class ComputerEngine implements Computer {
         return result;
     }
 
+    public static boolean isMicrogSigned(AndroidPackage p) {
+        // Allowlist the following apps:
+        // * com.android.vending - microG Companion
+        // * com.google.android.gms - microG Services
+        if (!p.getPackageName().equals("com.android.vending") &&
+                !p.getPackageName().equals("com.google.android.gms")) {
+            return false;
+        }
+        return Signature.areExactMatch(
+                p.getSigningDetails(), new Signature[]{MICROG_REAL_SIGNATURE});
+    }
+
+    private static Optional<Signature> generateFakeSignature(AndroidPackage p) {
+        if (!isMicrogSigned(p)) {
+            return Optional.empty();
+        }
+
+        Bundle metadata = p.getMetaData();
+        if (metadata == null) {
+            return Optional.empty();
+        }
+
+        String fakeSignatureStr = metadata.getString("fake-signature");
+        if (TextUtils.isEmpty(fakeSignatureStr)) {
+            return Optional.empty();
+        }
+
+        // Only MICROG_FAKE_SIGNATURE can be faked
+        Signature fakeSignature = new Signature(fakeSignatureStr);
+        if (!fakeSignature.equals(MICROG_FAKE_SIGNATURE)) {
+            return Optional.empty();
+        }
+
+        return Optional.of(fakeSignature);
+    }
+
     public final PackageInfo generatePackageInfo(PackageStateInternal ps,
             @PackageManager.PackageInfoFlagsBits long flags, int userId) {
         if (!mUserManager.exists(userId)) return null;
@@ -1511,6 +1553,10 @@ public class ComputerEngine implements Computer {
             packageInfo.packageName = packageInfo.applicationInfo.packageName =
                     resolveExternalPackageName(p);
 
+            generateFakeSignature(p).ifPresent(fakeSignature -> {
+                packageInfo.signatures = new Signature[]{fakeSignature};
+            });
+
             return packageInfo;
         } else if ((flags & (MATCH_UNINSTALLED_PACKAGES | MATCH_ARCHIVED_PACKAGES)) != 0
                 && PackageUserStateUtils.isAvailable(state, flags)) {
-- 
2.25.1