src/com/android/settings/network/PrivateDnsModeDialogPreference.java - platform/packages/apps/Settings - Git at Google

 /*
  * Copyright (C) 2017 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
 package com.android.settings.network;

 import static android.net.ConnectivityManager.PRIVATE_DNS_MODE_OFF;
 import static android.net.ConnectivityManager.PRIVATE_DNS_MODE_OPPORTUNISTIC;
 import static android.net.ConnectivityManager.PRIVATE_DNS_MODE_PROVIDER_HOSTNAME;
 import static android.system.OsConstants.AF_INET;
 import static android.system.OsConstants.AF_INET6;

 import android.app.AlertDialog;
 import android.content.ActivityNotFoundException;
 import android.content.ContentResolver;
 import android.content.Context;
 import android.content.DialogInterface;
 import android.content.Intent;
 import android.provider.Settings;
 import android.support.annotation.VisibleForTesting;
 import android.system.Os;
 import android.text.Editable;
 import android.text.TextWatcher;
 import android.text.method.LinkMovementMethod;
 import android.util.AttributeSet;
 import android.util.Log;
 import android.view.View;
 import android.widget.Button;
 import android.widget.EditText;
 import android.widget.RadioGroup;
 import android.widget.TextView;

 import com.android.internal.logging.nano.MetricsProto;
 import com.android.settings.R;
 import com.android.settings.overlay.FeatureFactory;
 import com.android.settings.utils.AnnotationSpan;
 import com.android.settingslib.CustomDialogPreference;
 import com.android.settingslib.HelpUtils;

 import java.net.InetAddress;
 import java.util.HashMap;
 import java.util.Map;

 /**
  * Dialog to set the Private DNS
  */
 public class PrivateDnsModeDialogPreference extends CustomDialogPreference implements
         DialogInterface.OnClickListener, RadioGroup.OnCheckedChangeListener, TextWatcher {

     public static final String ANNOTATION_URL = "url";

     private static final String TAG = "PrivateDnsModeDialog";
     // DNS_MODE -> RadioButton id
     private static final Map<String, Integer> PRIVATE_DNS_MAP;

     static {
         PRIVATE_DNS_MAP = new HashMap<>();
         PRIVATE_DNS_MAP.put(PRIVATE_DNS_MODE_OFF, R.id.private_dns_mode_off);
         PRIVATE_DNS_MAP.put(PRIVATE_DNS_MODE_OPPORTUNISTIC, R.id.private_dns_mode_opportunistic);
         PRIVATE_DNS_MAP.put(PRIVATE_DNS_MODE_PROVIDER_HOSTNAME, R.id.private_dns_mode_provider);
     }

     private static final int[] ADDRESS_FAMILIES = new int[]{AF_INET, AF_INET6};

     @VisibleForTesting
     static final String MODE_KEY = Settings.Global.PRIVATE_DNS_MODE;
     @VisibleForTesting
     static final String HOSTNAME_KEY = Settings.Global.PRIVATE_DNS_SPECIFIER;

     public static String getModeFromSettings(ContentResolver cr) {
         final String mode = Settings.Global.getString(cr, MODE_KEY);
         return PRIVATE_DNS_MAP.containsKey(mode) ? mode : PRIVATE_DNS_MODE_OPPORTUNISTIC;
     }

     public static String getHostnameFromSettings(ContentResolver cr) {
         return Settings.Global.getString(cr, HOSTNAME_KEY);
     }

     @VisibleForTesting
     EditText mEditText;
     @VisibleForTesting
     RadioGroup mRadioGroup;
     @VisibleForTesting
     String mMode;

     public PrivateDnsModeDialogPreference(Context context) {
         super(context);
     }

     public PrivateDnsModeDialogPreference(Context context, AttributeSet attrs) {
         super(context, attrs);
     }

     public PrivateDnsModeDialogPreference(Context context, AttributeSet attrs, int defStyleAttr) {
         super(context, attrs, defStyleAttr);
     }

     public PrivateDnsModeDialogPreference(Context context, AttributeSet attrs, int defStyleAttr,
             int defStyleRes) {
         super(context, attrs, defStyleAttr, defStyleRes);
     }

     private final AnnotationSpan.LinkInfo mUrlLinkInfo = new AnnotationSpan.LinkInfo(
             ANNOTATION_URL, (widget) -> {
         final Context context = widget.getContext();
         final Intent intent = HelpUtils.getHelpIntent(context,
                 context.getString(R.string.help_uri_private_dns),
                 context.getClass().getName());
         if (intent != null) {
             try {
                 widget.startActivityForResult(intent, 0);
             } catch (ActivityNotFoundException e) {
                 Log.w(TAG, "Activity was not found for intent, " + intent.toString());
             }
         }
     });

     @Override
     protected void onBindDialogView(View view) {
         final Context context = getContext();
         final ContentResolver contentResolver = context.getContentResolver();

         mMode = getModeFromSettings(context.getContentResolver());

         mEditText = view.findViewById(R.id.private_dns_mode_provider_hostname);
         mEditText.addTextChangedListener(this);
         mEditText.setText(getHostnameFromSettings(contentResolver));

         mRadioGroup = view.findViewById(R.id.private_dns_radio_group);
         mRadioGroup.setOnCheckedChangeListener(this);
         mRadioGroup.check(PRIVATE_DNS_MAP.getOrDefault(mMode, R.id.private_dns_mode_opportunistic));

         final TextView helpTextView = view.findViewById(R.id.private_dns_help_info);
         helpTextView.setMovementMethod(LinkMovementMethod.getInstance());
         final Intent helpIntent = HelpUtils.getHelpIntent(context,
                 context.getString(R.string.help_uri_private_dns),
                 context.getClass().getName());
         final AnnotationSpan.LinkInfo linkInfo = new AnnotationSpan.LinkInfo(context,
                 ANNOTATION_URL, helpIntent);
         if (linkInfo.isActionable()) {
             helpTextView.setText(AnnotationSpan.linkify(
                     context.getText(R.string.private_dns_help_message), linkInfo));
         }
     }

     @Override
     public void onClick(DialogInterface dialog, int which) {
         final Context context = getContext();
         if (mMode.equals(PRIVATE_DNS_MODE_PROVIDER_HOSTNAME)) {
             // Only clickable if hostname is valid, so we could save it safely
             Settings.Global.putString(context.getContentResolver(), HOSTNAME_KEY,
                     mEditText.getText().toString());
         }

         FeatureFactory.getFactory(context).getMetricsFeatureProvider().action(context,
                 MetricsProto.MetricsEvent.ACTION_PRIVATE_DNS_MODE, mMode);
         Settings.Global.putString(context.getContentResolver(), MODE_KEY, mMode);
     }

     @Override
     public void onCheckedChanged(RadioGroup group, int checkedId) {
         switch (checkedId) {
             case R.id.private_dns_mode_off:
                 mMode = PRIVATE_DNS_MODE_OFF;
                 break;
             case R.id.private_dns_mode_opportunistic:
                 mMode = PRIVATE_DNS_MODE_OPPORTUNISTIC;
                 break;
             case R.id.private_dns_mode_provider:
                 mMode = PRIVATE_DNS_MODE_PROVIDER_HOSTNAME;
                 break;
         }
         updateDialogInfo();
     }

     @Override
     public void beforeTextChanged(CharSequence s, int start, int count, int after) {
     }

     @Override
     public void onTextChanged(CharSequence s, int start, int before, int count) {
     }

     @Override
     public void afterTextChanged(Editable s) {
         updateDialogInfo();
     }

     private boolean isWeaklyValidatedHostname(String hostname) {
         // TODO(b/34953048): Use a validation method that permits more accurate,
         // but still inexpensive, checking of likely valid DNS hostnames.
         final String WEAK_HOSTNAME_REGEX = "^[a-zA-Z0-9_.-]+$";
         if (!hostname.matches(WEAK_HOSTNAME_REGEX)) {
             return false;
         }

         for (int address_family : ADDRESS_FAMILIES) {
             if (Os.inet_pton(address_family, hostname) != null) {
                 return false;
             }
         }

         return true;
     }

     private Button getSaveButton() {
         final AlertDialog dialog = (AlertDialog) getDialog();
         if (dialog == null) {
             return null;
         }
         return dialog.getButton(DialogInterface.BUTTON_POSITIVE);
     }

     private void updateDialogInfo() {
         final boolean modeProvider = PRIVATE_DNS_MODE_PROVIDER_HOSTNAME.equals(mMode);
         if (mEditText != null) {
             mEditText.setEnabled(modeProvider);
         }
         final Button saveButton = getSaveButton();
         if (saveButton != null) {
             saveButton.setEnabled(modeProvider
                     ? isWeaklyValidatedHostname(mEditText.getText().toString())
                     : true);
         }
     }
 }
	/*
	* Copyright (C) 2017 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/
	package com.android.settings.network;

	import static android.net.ConnectivityManager.PRIVATE_DNS_MODE_OFF;
	import static android.net.ConnectivityManager.PRIVATE_DNS_MODE_OPPORTUNISTIC;
	import static android.net.ConnectivityManager.PRIVATE_DNS_MODE_PROVIDER_HOSTNAME;
	import static android.system.OsConstants.AF_INET;
	import static android.system.OsConstants.AF_INET6;

	import android.app.AlertDialog;
	import android.content.ActivityNotFoundException;
	import android.content.ContentResolver;
	import android.content.Context;
	import android.content.DialogInterface;
	import android.content.Intent;
	import android.provider.Settings;
	import android.support.annotation.VisibleForTesting;
	import android.system.Os;
	import android.text.Editable;
	import android.text.TextWatcher;
	import android.text.method.LinkMovementMethod;
	import android.util.AttributeSet;
	import android.util.Log;
	import android.view.View;
	import android.widget.Button;
	import android.widget.EditText;
	import android.widget.RadioGroup;
	import android.widget.TextView;

	import com.android.internal.logging.nano.MetricsProto;
	import com.android.settings.R;
	import com.android.settings.overlay.FeatureFactory;
	import com.android.settings.utils.AnnotationSpan;
	import com.android.settingslib.CustomDialogPreference;
	import com.android.settingslib.HelpUtils;

	import java.net.InetAddress;
	import java.util.HashMap;
	import java.util.Map;

	/**
	* Dialog to set the Private DNS
	*/
	public class PrivateDnsModeDialogPreference extends CustomDialogPreference implements
	DialogInterface.OnClickListener, RadioGroup.OnCheckedChangeListener, TextWatcher {

	public static final String ANNOTATION_URL = "url";

	private static final String TAG = "PrivateDnsModeDialog";
	// DNS_MODE -> RadioButton id
	private static final Map<String, Integer> PRIVATE_DNS_MAP;

	static {
	PRIVATE_DNS_MAP = new HashMap<>();
	PRIVATE_DNS_MAP.put(PRIVATE_DNS_MODE_OFF, R.id.private_dns_mode_off);
	PRIVATE_DNS_MAP.put(PRIVATE_DNS_MODE_OPPORTUNISTIC, R.id.private_dns_mode_opportunistic);
	PRIVATE_DNS_MAP.put(PRIVATE_DNS_MODE_PROVIDER_HOSTNAME, R.id.private_dns_mode_provider);
	}

	private static final int[] ADDRESS_FAMILIES = new int[]{AF_INET, AF_INET6};

	@VisibleForTesting
	static final String MODE_KEY = Settings.Global.PRIVATE_DNS_MODE;
	@VisibleForTesting
	static final String HOSTNAME_KEY = Settings.Global.PRIVATE_DNS_SPECIFIER;

	public static String getModeFromSettings(ContentResolver cr) {
	final String mode = Settings.Global.getString(cr, MODE_KEY);
	return PRIVATE_DNS_MAP.containsKey(mode) ? mode : PRIVATE_DNS_MODE_OPPORTUNISTIC;
	}

	public static String getHostnameFromSettings(ContentResolver cr) {
	return Settings.Global.getString(cr, HOSTNAME_KEY);
	}

	@VisibleForTesting
	EditText mEditText;
	@VisibleForTesting
	RadioGroup mRadioGroup;
	@VisibleForTesting
	String mMode;

	public PrivateDnsModeDialogPreference(Context context) {
	super(context);
	}

	public PrivateDnsModeDialogPreference(Context context, AttributeSet attrs) {
	super(context, attrs);
	}

	public PrivateDnsModeDialogPreference(Context context, AttributeSet attrs, int defStyleAttr) {
	super(context, attrs, defStyleAttr);
	}

	public PrivateDnsModeDialogPreference(Context context, AttributeSet attrs, int defStyleAttr,
	int defStyleRes) {
	super(context, attrs, defStyleAttr, defStyleRes);
	}

	private final AnnotationSpan.LinkInfo mUrlLinkInfo = new AnnotationSpan.LinkInfo(
	ANNOTATION_URL, (widget) -> {
	final Context context = widget.getContext();
	final Intent intent = HelpUtils.getHelpIntent(context,
	context.getString(R.string.help_uri_private_dns),
	context.getClass().getName());
	if (intent != null) {
	try {
	widget.startActivityForResult(intent, 0);
	} catch (ActivityNotFoundException e) {
	Log.w(TAG, "Activity was not found for intent, " + intent.toString());
	}
	}
	});

	@Override
	protected void onBindDialogView(View view) {
	final Context context = getContext();
	final ContentResolver contentResolver = context.getContentResolver();

	mMode = getModeFromSettings(context.getContentResolver());

	mEditText = view.findViewById(R.id.private_dns_mode_provider_hostname);
	mEditText.addTextChangedListener(this);
	mEditText.setText(getHostnameFromSettings(contentResolver));

	mRadioGroup = view.findViewById(R.id.private_dns_radio_group);
	mRadioGroup.setOnCheckedChangeListener(this);
	mRadioGroup.check(PRIVATE_DNS_MAP.getOrDefault(mMode, R.id.private_dns_mode_opportunistic));

	final TextView helpTextView = view.findViewById(R.id.private_dns_help_info);
	helpTextView.setMovementMethod(LinkMovementMethod.getInstance());
	final Intent helpIntent = HelpUtils.getHelpIntent(context,
	context.getString(R.string.help_uri_private_dns),
	context.getClass().getName());
	final AnnotationSpan.LinkInfo linkInfo = new AnnotationSpan.LinkInfo(context,
	ANNOTATION_URL, helpIntent);
	if (linkInfo.isActionable()) {
	helpTextView.setText(AnnotationSpan.linkify(
	context.getText(R.string.private_dns_help_message), linkInfo));
	}
	}

	@Override
	public void onClick(DialogInterface dialog, int which) {
	final Context context = getContext();
	if (mMode.equals(PRIVATE_DNS_MODE_PROVIDER_HOSTNAME)) {
	// Only clickable if hostname is valid, so we could save it safely
	Settings.Global.putString(context.getContentResolver(), HOSTNAME_KEY,
	mEditText.getText().toString());
	}

	FeatureFactory.getFactory(context).getMetricsFeatureProvider().action(context,
	MetricsProto.MetricsEvent.ACTION_PRIVATE_DNS_MODE, mMode);
	Settings.Global.putString(context.getContentResolver(), MODE_KEY, mMode);
	}

	@Override
	public void onCheckedChanged(RadioGroup group, int checkedId) {
	switch (checkedId) {
	case R.id.private_dns_mode_off:
	mMode = PRIVATE_DNS_MODE_OFF;
	break;
	case R.id.private_dns_mode_opportunistic:
	mMode = PRIVATE_DNS_MODE_OPPORTUNISTIC;
	break;
	case R.id.private_dns_mode_provider:
	mMode = PRIVATE_DNS_MODE_PROVIDER_HOSTNAME;
	break;
	}
	updateDialogInfo();
	}

	@Override
	public void beforeTextChanged(CharSequence s, int start, int count, int after) {
	}

	@Override
	public void onTextChanged(CharSequence s, int start, int before, int count) {
	}

	@Override
	public void afterTextChanged(Editable s) {
	updateDialogInfo();
	}

	private boolean isWeaklyValidatedHostname(String hostname) {
	// TODO(b/34953048): Use a validation method that permits more accurate,
	// but still inexpensive, checking of likely valid DNS hostnames.
	final String WEAK_HOSTNAME_REGEX = "^[a-zA-Z0-9_.-]+$";
	if (!hostname.matches(WEAK_HOSTNAME_REGEX)) {
	return false;
	}

	for (int address_family : ADDRESS_FAMILIES) {
	if (Os.inet_pton(address_family, hostname) != null) {
	return false;
	}
	}

	return true;
	}

	private Button getSaveButton() {
	final AlertDialog dialog = (AlertDialog) getDialog();
	if (dialog == null) {
	return null;
	}
	return dialog.getButton(DialogInterface.BUTTON_POSITIVE);
	}

	private void updateDialogInfo() {
	final boolean modeProvider = PRIVATE_DNS_MODE_PROVIDER_HOSTNAME.equals(mMode);
	if (mEditText != null) {
	mEditText.setEnabled(modeProvider);
	}
	final Button saveButton = getSaveButton();
	if (saveButton != null) {
	saveButton.setEnabled(modeProvider
	? isWeaklyValidatedHostname(mEditText.getText().toString())
	: true);
	}
	}
	}