2 files changed, 41 insertions, 8 deletions

diff --git a/src/com/android/settings/applications/InstalledAppDetails.java b/src/com/android/settings/applications/InstalledAppDetails.java
index 778ef44..4091b13 100644
--- a/src/com/android/settings/applications/InstalledAppDetails.java
+++ b/src/com/android/settings/applications/InstalledAppDetails.java
@@ -401,10 +401,19 @@ public class InstalledAppDetails extends Fragment
     }
 
     private void initPrivacyGuardButton() {
-        // TODO: We probably want to disable this optional for the built-in apps
-        boolean enabled = mPm.getPrivacyGuardSetting(mAppEntry.info.packageName);
-        mPrivacyGuardSwitch.setChecked(enabled);
-        mPrivacyGuardSwitch.setOnCheckedChangeListener(this);
+        if (mPrivacyGuardSwitch == null) {
+            return;
+        }
+
+        mPrivacyGuardSwitch.setChecked(mPm.getPrivacyGuardSetting(mAppEntry.info.packageName));
+
+        // disable privacy guard switch if the app is signed with the platform certificate
+        // to avoid the user shooting himself in the foot
+        if (isThisASystemPackage()) {
+            mPrivacyGuardSwitch.setEnabled(false);
+        } else {
+            mPrivacyGuardSwitch.setOnCheckedChangeListener(this);
+        }
     }
 
     /** Called when the activity is first created. */
@@ -1201,10 +1210,17 @@ public class InstalledAppDetails extends Fragment
                     .setNegativeButton(R.string.dlg_cancel, null)
                     .create();
                 case DLG_PRIVACY_GUARD:
+                    final int messageResId;
+                    if ((getOwner().mAppEntry.info.flags & ApplicationInfo.FLAG_SYSTEM) != 0) {
+                        messageResId = R.string.privacy_guard_dlg_system_app_text;
+                    } else {
+                        messageResId = R.string.privacy_guard_dlg_text;
+                    }
+
                     return new AlertDialog.Builder(getActivity())
-                    .setTitle(getActivity().getText(R.string.privacy_guard_dlg_title))
+                    .setTitle(R.string.privacy_guard_dlg_title)
                     .setIconAttribute(android.R.attr.alertDialogIcon)
-                    .setMessage(getActivity().getText(R.string.privacy_guard_dlg_text))
+                    .setMessage(messageResId)
                     .setPositiveButton(R.string.dlg_ok,
                         new DialogInterface.OnClickListener() {
                         public void onClick(DialogInterface dialog, int which) {
diff --git a/src/com/android/settings/cyanogenmod/privacyguard/PrivacyGuardManager.java b/src/com/android/settings/cyanogenmod/privacyguard/PrivacyGuardManager.java
index efb05a4..9e27147 100644
--- a/src/com/android/settings/cyanogenmod/privacyguard/PrivacyGuardManager.java
+++ b/src/com/android/settings/cyanogenmod/privacyguard/PrivacyGuardManager.java
@@ -27,6 +27,7 @@ import android.content.Intent;
 import android.content.pm.ApplicationInfo;
 import android.content.pm.PackageInfo;
 import android.content.pm.PackageManager;
+import android.content.pm.Signature;
 import android.content.SharedPreferences;
 import android.net.Uri;
 import android.os.Bundle;
@@ -195,14 +196,30 @@ public class PrivacyGuardManager extends Fragment
     */
     private List<AppInfo> loadInstalledApps() {
         List<AppInfo> apps = new ArrayList<AppInfo>();
-        List<PackageInfo> packages = mPm.getInstalledPackages(PackageManager.GET_PERMISSIONS);
+        List<PackageInfo> packages = mPm.getInstalledPackages(
+            PackageManager.GET_PERMISSIONS | PackageManager.GET_SIGNATURES);
         boolean showSystemApps = shouldShowSystemApps();
         boolean filterByPermission = shouldFilterByPermission();
+        Signature platformCert;
+
+        try {
+            PackageInfo sysInfo = mPm.getPackageInfo("android", PackageManager.GET_SIGNATURES);
+            platformCert = sysInfo.signatures[0];
+        } catch (PackageManager.NameNotFoundException e) {
+            platformCert = null;
+        }
 
         for (PackageInfo info : packages) {
             final ApplicationInfo appInfo = info.applicationInfo;
 
-            // skip system apps if they shall not be included
+            // hide apps signed with the platform certificate to avoid the user
+            // shooting himself in the foot
+            if (platformCert != null && info.signatures != null
+                    && platformCert.equals(info.signatures[0])) {
+                continue;
+            }
+
+            // skip all system apps if they shall not be included
             if (!showSystemApps && (appInfo.flags & ApplicationInfo.FLAG_SYSTEM) != 0) {
                 continue;
             }