Fixed restricting browser user agent

Fixes #825

CHANGELOG.md

@@ -4,6 +4,7 @@ Changelog
 **Next release**
 
 * Fixed Android KitKat message permissions
+* Fixed restricting browser user agent ([issue](https://github.com/M66B/XPrivacy/issues/825))
 * Do not disable Android/extra usage data when not in expert mode
 * Separate setting to enable restricting dangerous functions, thanks @[jpeg729](https://github.com/jpeg729)
 * Show exported file name while sharing, thanks @[jpeg729](https://github.com/jpeg729)

assets/meta.xml

@@ -196,9 +196,6 @@
     <Hook restriction="system" method="android.intent.action.EXTERNAL_APPLICATIONS_UNAVAILABLE" dangerous="true" permissions="" sdk="14" />
     <Hook restriction="system" method="ApplicationsProvider" permissions="" sdk="14" />
 
-    <Hook restriction="view" method="getDefaultUserAgent" permissions="" sdk="17" />
-    <Hook restriction="view" method="getDefaultUserAgentForLocale" permissions="" sdk="17" />
-    <Hook restriction="view" method="getUserAgentString" permissions="" sdk="3" />
-    <Hook restriction="view" method="setUserAgentString" permissions="" sdk="3" />
+    <Hook restriction="view" method="getSettings" permissions="" sdk="1" />
     <Hook restriction="view" method="android.intent.action.VIEW" permissions="" sdk="14" />
 </Meta>

src/biz/bokhorst/xprivacy/XPrivacy.java

@@ -118,9 +118,8 @@ public void initZygote(StartupParam startupParam) throws Throwable {
 		// Telephony
 		hookAll(XTelephonyManager.getInstances());
 
-		// Web settings
-		hookAll(XWebSettings.getInstances());
-		hookAll(XWebSettingsClassic.getInstances());
+		// Web view
+		hookAll(XWebView.getInstances());
 
 		// Wi-Fi manager
 		hookAll(XWifiManager.getInstances());

src/biz/bokhorst/xprivacy/XWebView.java

@@ -0,0 +1,106 @@
+package biz.bokhorst.xprivacy;
+
+import java.lang.reflect.Method;
+import java.util.ArrayList;
+import java.util.List;
+
+import android.content.Context;
+import android.os.Binder;
+import android.util.Log;
+
+import de.robv.android.xposed.XC_MethodHook;
+import de.robv.android.xposed.XposedBridge;
+import de.robv.android.xposed.XC_MethodHook.MethodHookParam;
+
+public class XWebView extends XHook {
+	private Methods mMethod;
+	private static final List<String> mWebSettings = new ArrayList<String>();
+
+	private XWebView(Methods method, String restrictionName) {
+		super(restrictionName, method.name(), null);
+		mMethod = method;
+	}
+
+	public String getClassName() {
+		return "android.webkit.WebView";
+	}
+
+	// public WebSettings getSettings()
+	// frameworks/base/core/java/android/webkit/WebView.java
+	// http://developer.android.com/reference/android/webkit/WebView.html
+
+	// public synchronize String getUserAgentString()
+	// public synchronized void setUserAgentString (String ua)
+	// frameworks/base/core/java/android/webkit/WebSettings.java
+	// http://developer.android.com/reference/android/webkit/WebSettings.html
+
+	private enum Methods {
+		getSettings
+	};
+
+	public static List<XHook> getInstances() {
+		List<XHook> listHook = new ArrayList<XHook>();
+		listHook.add(new XWebView(Methods.getSettings, PrivacyManager.cView));
+		return listHook;
+	}
+
+	@Override
+	protected void before(MethodHookParam param) throws Throwable {
+		// Do nothing
+	}
+
+	@Override
+	protected void after(MethodHookParam param) throws Throwable {
+		if (mMethod == Methods.getSettings) {
+			if (param.getResult() != null) {
+				// Check web settings type
+				Class<?> clazzWebSettings = param.getResultOrThrowable().getClass();
+				if (!mWebSettings.contains(clazzWebSettings.getName())) {
+					mWebSettings.add(clazzWebSettings.getName());
+					Util.log(this, Log.INFO, "Hooking " + clazzWebSettings.getName());
+
+					// getUserAgentString
+					try {
+						Method getUserAgentString = clazzWebSettings.getDeclaredMethod("getUserAgentString");
+						Util.log(this, Log.INFO, "Hooking " + getUserAgentString.getName());
+						XposedBridge.hookMethod(getUserAgentString, new XC_MethodHook() {
+							@Override
+							protected void afterHookedMethod(MethodHookParam param) throws Throwable {
+								if (isRestricted(param))
+									param.setResult(PrivacyManager.getDefacedProp(Binder.getCallingUid(), "UA"));
+							}
+						});
+					} catch (NoSuchFieldError ex) {
+						Util.bug(this, ex);
+					}
+
+					// setUserAgentString
+					try {
+						Method setUserAgentString = clazzWebSettings.getDeclaredMethod("setUserAgentString",
+								String.class);
+						Util.log(this, Log.INFO, "Hooking " + setUserAgentString.getName());
+						XposedBridge.hookMethod(setUserAgentString, new XC_MethodHook() {
+							@Override
+							protected void beforeHookedMethod(MethodHookParam param) throws Throwable {
+								if (isRestricted(param))
+									param.args[0] = PrivacyManager.getDefacedProp(Binder.getCallingUid(), "UA");
+							}
+						});
+					} catch (NoSuchFieldError ex) {
+						Util.bug(this, ex);
+					}
+				}
+			}
+		} else
+			Util.log(this, Log.WARN, "Unknown method=" + param.method.getName());
+	}
+
+	@Override
+	protected boolean isRestricted(MethodHookParam param) throws Throwable {
+		Context context = null;
+		if (param.args.length > 0)
+			context = (Context) param.args[0];
+		int uid = Binder.getCallingUid();
+		return getRestricted(context, uid, true);
+	}
+}