Verify package signature

microg · Mar 5, 2024 · b399e09 · b399e09
1 parent 07c9829
commit b399e09
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Showing 2 changed files with 51 additions and 22 deletions.
diff --git a/play-services-base/src/main/java/org/microg/gms/common/MultiConnectionKeeper.java b/play-services-base/src/main/java/org/microg/gms/common/MultiConnectionKeeper.java
@@ -22,74 +22,102 @@
 import android.content.Intent;
 import android.content.ServiceConnection;
 import android.content.SharedPreferences;
-import android.content.pm.ApplicationInfo;
 import android.content.pm.PackageManager;
 import android.content.pm.PermissionInfo;
 import android.content.pm.ResolveInfo;
+import android.content.pm.Signature;
 import android.os.IBinder;
 import android.util.Log;
 
+import java.util.Arrays;
 import java.util.HashMap;
 import java.util.HashSet;
+import java.util.List;
 import java.util.Map;
 import java.util.Set;
 
 import static android.os.Build.VERSION.SDK_INT;
 import static android.os.Build.VERSION_CODES.ICE_CREAM_SANDWICH;
-import static android.os.Build.VERSION_CODES.TIRAMISU;
 import static org.microg.gms.common.Constants.GMS_PACKAGE_NAME;
 import static org.microg.gms.common.Constants.GMS_MINUS_PACKAGE_NAME;
+import static org.microg.gms.common.Constants.GMS_PACKAGE_SIGNATURE_SHA1;
+import static org.microg.gms.common.Constants.GMS_SECONDARY_PACKAGE_SIGNATURE_SHA1;
+import static org.microg.gms.common.Constants.MICROG_PACKAGE_SIGNATURE_SHA1;
 
 public class MultiConnectionKeeper {
  private static final String TAG = "GmsMultiConKeeper";
  private static final String PREF_MASTER = "GmsMultiConKeeper";
  private static final String PREF_TARGET = "GmsMultiConKeeper_target";
+ private static final String GOOGLE_APP_KEY = "24bb24c05e47e0aefa68a58a766179d9b613a600";
+ private static final String[] GOOGLE_PRIMARY_KEYS = {GMS_PACKAGE_SIGNATURE_SHA1, GMS_SECONDARY_PACKAGE_SIGNATURE_SHA1, GOOGLE_APP_KEY};
 
+ private static final String[] MICROG_PRIMARY_KEYS = {MICROG_PACKAGE_SIGNATURE_SHA1};
  private static MultiConnectionKeeper INSTANCE;
 
  private final Context context;
 
  private final String gmsPackage;
  private final Map<String, Connection> connections = new HashMap<String, Connection>();
 
- private String getApplicationName(String packageId) throws PackageManager.NameNotFoundException {
- ApplicationInfo ai;
- if (SDK_INT >= TIRAMISU) {
- ai = context.getPackageManager().getApplicationInfo(
- packageId,
- PackageManager.ApplicationInfoFlags.of(
- PackageManager.GET_META_DATA
- )
- );
- } else {
- ai = context.getPackageManager().getApplicationInfo(packageId, 0);
+ private Boolean isGoogleOrMicrogSig(PackageManager pm, String packageId) throws PackageManager.NameNotFoundException {
+ List<String> signatures = Arrays.asList(GOOGLE_PRIMARY_KEYS);
+ signatures.addAll(Arrays.asList(MICROG_PRIMARY_KEYS));
+ return signatureIsIn(pm, packageId, signatures);
+ }
+
+ private Boolean isMicrogSig(PackageManager pm, String packageId) throws PackageManager.NameNotFoundException {
+ List<String> signatures = Arrays.asList(MICROG_PRIMARY_KEYS);
+ return signatureIsIn(pm, packageId, signatures);
+ }
+
+ private Boolean signatureIsIn(PackageManager pm, String packageId, List<String> signatures) throws PackageManager.NameNotFoundException {
+ Signature[] appSignatures = pm.getPackageInfo(packageId, PackageManager.GET_SIGNATURES).signatures;
+ for (Signature sig : appSignatures) {
+ if (sig != null && signatures.contains(sha1sum(sig.toByteArray())))
+ return true;
+ }
+ return false;
+ }
+
+ private String sha1sum(byte[] bytes) {
+ MessageDigest md;
+ try {
+ md = MessageDigest.getInstance("SHA1");
+ } catch (final NoSuchAlgorithmException e) {
+ return null;
  }
- return (String) context.getPackageManager().getApplicationLabel(ai);
+ if (md != null) {
+ bytes = md.digest(bytes);
+ if (bytes != null) {
+ StringBuilder sb = new StringBuilder(2 * bytes.length);
+ for (byte b : bytes) {
+ sb.append(String.format("%02x", b));
+ }
+ return sb.toString();
+ }
+ }
+ return null;
  }
 
  private String getTargetPackageWithoutPref() {
  // Pref: gms > microG > self
  PackageManager pm = context.getPackageManager();
  try {
- // We check the application has an activity and its name to avoid any fraudulent
- // app impersonating microG, "Cooking app" with com.google.android.gms id
- String name = getApplicationName(GMS_PACKAGE_NAME);
- if (name.contains("Google Play") || name.contains("microG")) {
+ if (isGoogleOrMicrogSig(pm, GMS_PACKAGE_NAME)) {
  Log.d(TAG, GMS_PACKAGE_NAME + " found !");
  return GMS_PACKAGE_NAME;
  } else {
- Log.w(TAG, GMS_MINUS_PACKAGE_NAME + " found with another name: " + name);
+ Log.w(TAG, GMS_PACKAGE_NAME + " found with another signature");
  }
  } catch (PackageManager.NameNotFoundException e) {
  Log.d(TAG, GMS_PACKAGE_NAME + " not found");
  }
  try {
- String name = getApplicationName(GMS_MINUS_PACKAGE_NAME);
- if (name.contains("microG")) {
+ if (isMicrogSig(pm, GMS_MINUS_PACKAGE_NAME)) {
  Log.d(TAG, GMS_MINUS_PACKAGE_NAME + " found !");
  return GMS_MINUS_PACKAGE_NAME;
  } else {
- Log.w(TAG, GMS_MINUS_PACKAGE_NAME + " found with another name: " + name);
+ Log.w(TAG, GMS_MINUS_PACKAGE_NAME + " found with another signature");
  }
  } catch (PackageManager.NameNotFoundException e) {
  Log.d(TAG, GMS_MINUS_PACKAGE_NAME + " not found");

diff --git a/play-services-basement/src/main/java/org/microg/gms/common/Constants.java b/play-services-basement/src/main/java/org/microg/gms/common/Constants.java
@@ -25,6 +25,7 @@ public class Constants {
  public static final String GSF_PACKAGE_NAME = "com.google.android.gsf";
  public static final String GMS_PACKAGE_SIGNATURE_SHA1 = "38918a453d07199354f8b19af05ec6562ced5788";
  public static final String GMS_SECONDARY_PACKAGE_SIGNATURE_SHA1 = "bd32424203e0fb25f36b57e5aa356f9bdd1da998";
+ public static final String MICROG_PACKAGE_SIGNATURE_SHA1 = "10321bd893f69af97f7573aafe9de1dc0901f3a1";
  @Deprecated
  public static final int MAX_REFERENCE_VERSION = GMS_VERSION_CODE;
 }