Fix several HTTP proxy issues with multinetworking.

1. Send PROXY_CHANGE_ACTION broadcast when any network's proxy changes,
   not just the default network.
2. When a process is bound to a particular Network, update the proxy
   system properties to those for the bound Network, and keep them
   updated when PROXY_CHANGE_ACTION broadcasts are received.
3. Make Network.openConnection() use the proxy for the Network.

bug:17905627
bug:17420465
bug:18144582

(cherry-pick of https://android-review.googlesource.com/#/c/115170)

Change-Id: Ia2819985e6108a8c121e74c683a5646becfd0a97

core/java/android/app/ActivityThread.java

@@ -44,7 +44,10 @@
 import android.graphics.Bitmap;
 import android.graphics.Canvas;
 import android.hardware.display.DisplayManagerGlobal;
+import android.net.ConnectivityManager;
 import android.net.IConnectivityManager;
+import android.net.LinkProperties;
+import android.net.Network;
 import android.net.Proxy;
 import android.net.ProxyInfo;
 import android.net.Uri;
@@ -839,7 +842,13 @@ public void clearDnsCache() {
         }
 
         public void setHttpProxy(String host, String port, String exclList, Uri pacFileUrl) {
-            Proxy.setHttpProxySystemProperty(host, port, exclList, pacFileUrl);
+            final Network network = ConnectivityManager.getProcessDefaultNetwork();
+            if (network != null) {
+                Proxy.setHttpProxySystemProperty(
+                        ConnectivityManager.from(getSystemContext()).getDefaultProxy());
+            } else {
+                Proxy.setHttpProxySystemProperty(host, port, exclList, pacFileUrl);
+            }
         }
 
         public void processInBackground() {
@@ -4430,7 +4439,7 @@ private void handleBindApplication(AppBindData data) {
             // crash if we can't get it.
             IConnectivityManager service = IConnectivityManager.Stub.asInterface(b);
             try {
-                ProxyInfo proxyInfo = service.getProxy();
+                final ProxyInfo proxyInfo = service.getDefaultProxy();
                 Proxy.setHttpProxySystemProperty(proxyInfo);
             } catch (RemoteException e) {}
         }

core/java/android/net/ConnectivityManager.java

@@ -452,6 +452,13 @@ public class ConnectivityManager {
     public static final int NETID_UNSET = 0;
 
     private final IConnectivityManager mService;
+    /**
+     * A kludge to facilitate static access where a Context pointer isn't available, like in the
+     * case of the static set/getProcessDefaultNetwork methods and from the Network class.
+     * TODO: Remove this after deprecating the static methods in favor of non-static methods or
+     * methods that take a Context argument.
+     */
+    private static ConnectivityManager sInstance;
 
     private INetworkManagementService mNMService;
 
@@ -1397,6 +1404,7 @@ public boolean isDefaultNetworkActive() {
      */
     public ConnectivityManager(IConnectivityManager service) {
         mService = checkNotNull(service, "missing IConnectivityManager");
+        sInstance = this;
     }
 
     /** {@hide} */
@@ -1418,6 +1426,18 @@ public static final void enforceTetherChangePermission(Context context) {
         }
     }
 
+    /**
+     * @deprecated - use getSystemService. This is a kludge to support static access in certain
+     *               situations where a Context pointer is unavailable.
+     * @hide
+     */
+    public static ConnectivityManager getInstance() {
+        if (sInstance == null) {
+            throw new IllegalStateException("No ConnectivityManager yet constructed");
+        }
+        return sInstance;
+    }
+
     /**
      * Get the set of tetherable, available interfaces.  This list is limited by
      * device configuration and current interface existence.
@@ -1749,20 +1769,26 @@ public ProxyInfo getGlobalProxy() {
     }
 
     /**
-     * Get the HTTP proxy settings for the current default network.  Note that
-     * if a global proxy is set, it will override any per-network setting.
+     * Get the current default HTTP proxy settings.  If a global proxy is set it will be returned,
+     * otherwise if this process is bound to a {@link Network} using
+     * {@link #setProcessDefaultNetwork} then that {@code Network}'s proxy is returned, otherwise
+     * the default network's proxy is returned.
      *
      * @return the {@link ProxyInfo} for the current HTTP proxy, or {@code null} if no
      *        HTTP proxy is active.
-     *
-     * <p>This method requires the call to hold the permission
-     * {@link android.Manifest.permission#ACCESS_NETWORK_STATE}.
-     * {@hide}
-     * @deprecated Deprecated in favor of {@link #getLinkProperties}
+     * @hide
      */
-    public ProxyInfo getProxy() {
+    public ProxyInfo getDefaultProxy() {
+        final Network network = getProcessDefaultNetwork();
+        if (network != null) {
+            final ProxyInfo globalProxy = getGlobalProxy();
+            if (globalProxy != null) return globalProxy;
+            final LinkProperties lp = getLinkProperties(network);
+            if (lp != null) return lp.getHttpProxy();
+            return null;
+        }
         try {
-            return mService.getProxy();
+            return mService.getDefaultProxy();
         } catch (RemoteException e) {
             return null;
         }
@@ -2475,6 +2501,9 @@ public static boolean setProcessDefaultNetwork(Network network) {
             return true;
         }
         if (NetworkUtils.bindProcessToNetwork(netId)) {
+            // Set HTTP proxy system properties to match network.
+            // TODO: Deprecate this static method and replace it with a non-static version.
+            Proxy.setHttpProxySystemProperty(getInstance().getDefaultProxy());
             // Must flush DNS cache as new network may have different DNS resolutions.
             InetAddress.clearDnsCache();
             // Must flush socket pool as idle sockets will be bound to previous network and may

core/java/android/net/IConnectivityManager.aidl

@@ -100,7 +100,7 @@ interface IConnectivityManager
 
     void setGlobalProxy(in ProxyInfo p);
 
-    ProxyInfo getProxy();
+    ProxyInfo getDefaultProxy();
 
     void setDataDependency(int networkType, boolean met);
 

core/java/android/net/Network.java

@@ -27,6 +27,7 @@
 import java.net.InetAddress;
 import java.net.InetSocketAddress;
 import java.net.MalformedURLException;
+import java.net.ProxySelector;
 import java.net.Socket;
 import java.net.SocketAddress;
 import java.net.SocketException;
@@ -244,16 +245,46 @@ public InetAddress[] getAllByName(String host) throws UnknownHostException {
      * @see java.net.URL#openConnection()
      */
     public URLConnection openConnection(URL url) throws IOException {
+        final ConnectivityManager cm = ConnectivityManager.getInstance();
+        // TODO: Should this be optimized to avoid fetching the global proxy for every request?
+        ProxyInfo proxyInfo = cm.getGlobalProxy();
+        if (proxyInfo == null) {
+            // TODO: Should this be optimized to avoid fetching LinkProperties for every request?
+            final LinkProperties lp = cm.getLinkProperties(this);
+            if (lp != null) proxyInfo = lp.getHttpProxy();
+        }
+        java.net.Proxy proxy = null;
+        if (proxyInfo != null) {
+            proxy = proxyInfo.makeProxy();
+        } else {
+            proxy = java.net.Proxy.NO_PROXY;
+        }
+        return openConnection(url, proxy);
+    }
+
+    /**
+     * Opens the specified {@link URL} on this {@code Network}, such that all traffic will be sent
+     * on this Network. The URL protocol must be {@code HTTP} or {@code HTTPS}.
+     *
+     * @param proxy the proxy through which the connection will be established.
+     * @return a {@code URLConnection} to the resource referred to by this URL.
+     * @throws MalformedURLException if the URL protocol is not HTTP or HTTPS.
+     * @throws IllegalArgumentException if the argument proxy is null.
+     * @throws IOException if an error occurs while opening the connection.
+     * @see java.net.URL#openConnection()
+     * @hide
+     */
+    public URLConnection openConnection(URL url, java.net.Proxy proxy) throws IOException {
+        if (proxy == null) throw new IllegalArgumentException("proxy is null");
         maybeInitHttpClient();
         String protocol = url.getProtocol();
         OkHttpClient client;
         // TODO: HttpHandler creates OkHttpClients that share the default ResponseCache.
         // Could this cause unexpected behavior?
-        // TODO: Should the network's proxy be specified?
         if (protocol.equals("http")) {
-            client = HttpHandler.createHttpOkHttpClient(null /* proxy */);
+            client = HttpHandler.createHttpOkHttpClient(proxy);
         } else if (protocol.equals("https")) {
-            client = HttpsHandler.createHttpsOkHttpClient(null /* proxy */);
+            client = HttpsHandler.createHttpsOkHttpClient(proxy);
         } else {
             // OkHttpClient only supports HTTP and HTTPS and returns a null URLStreamHandler if
             // passed another protocol.

core/java/android/net/ProxyInfo.java

@@ -260,7 +260,8 @@ public String toString() {
         if (!Uri.EMPTY.equals(mPacFileUrl)) {
             sb.append("PAC Script: ");
             sb.append(mPacFileUrl);
-        } else if (mHost != null) {
+        }
+        if (mHost != null) {
             sb.append("[");
             sb.append(mHost);
             sb.append("] ");

packages/CaptivePortalLogin/src/com/android/captiveportallogin/CaptivePortalLoginActivity.java

@@ -23,12 +23,10 @@
 import android.graphics.Bitmap;
 import android.net.ConnectivityManager;
 import android.net.ConnectivityManager.NetworkCallback;
-import android.net.LinkProperties;
 import android.net.Network;
 import android.net.NetworkCapabilities;
 import android.net.NetworkRequest;
 import android.net.Proxy;
-import android.net.ProxyInfo;
 import android.net.Uri;
 import android.os.Bundle;
 import android.provider.Settings;
@@ -96,26 +94,10 @@ protected void onCreate(Bundle savedInstanceState) {
             done(CAPTIVE_PORTAL_APP_RETURN_WANTED_AS_IS);
         }
 
+        final ConnectivityManager cm = ConnectivityManager.from(this);
         final Network network = new Network(mNetId);
-        ConnectivityManager.setProcessDefaultNetwork(network);
-
-        // Set HTTP proxy system properties to those of the selected Network.
-        final LinkProperties lp = ConnectivityManager.from(this).getLinkProperties(network);
-        if (lp != null) {
-            final ProxyInfo proxyInfo = lp.getHttpProxy();
-            String host = "";
-            String port = "";
-            String exclList = "";
-            Uri pacFileUrl = Uri.EMPTY;
-            if (proxyInfo != null) {
-                host = proxyInfo.getHost();
-                port = Integer.toString(proxyInfo.getPort());
-                exclList = proxyInfo.getExclusionListAsString();
-                pacFileUrl = proxyInfo.getPacFileUrl();
-            }
-            Proxy.setHttpProxySystemProperty(host, port, exclList, pacFileUrl);
-            Log.v(TAG, "Set proxy system properties to " + proxyInfo);
-        }
+        // Also initializes proxy system properties.
+        cm.setProcessDefaultNetwork(network);
 
         // Proxy system properties must be initialized before setContentView is called because
         // setContentView initializes the WebView logic which in turn reads the system properties.
@@ -124,8 +106,7 @@ protected void onCreate(Bundle savedInstanceState) {
         getActionBar().setDisplayShowHomeEnabled(false);
 
         // Exit app if Network disappears.
-        final NetworkCapabilities networkCapabilities =
-                ConnectivityManager.from(this).getNetworkCapabilities(network);
+        final NetworkCapabilities networkCapabilities = cm.getNetworkCapabilities(network);
         if (networkCapabilities == null) {
             finish();
             return;
@@ -140,7 +121,7 @@ public void onLost(Network lostNetwork) {
         for (int transportType : networkCapabilities.getTransportTypes()) {
             builder.addTransportType(transportType);
         }
-        ConnectivityManager.from(this).registerNetworkCallback(builder.build(), mNetworkCallback);
+        cm.registerNetworkCallback(builder.build(), mNetworkCallback);
 
         final WebView myWebView = (WebView) findViewById(R.id.webview);
         myWebView.clearCache(true);

services/core/java/com/android/server/ConnectivityService.java

@@ -2618,7 +2618,7 @@ public void reportBadNetwork(Network network) {
         }
     }
 
-    public ProxyInfo getProxy() {
+    public ProxyInfo getDefaultProxy() {
         // this information is already available as a world read/writable jvm property
         // so this API change wouldn't have a benifit.  It also breaks the passing
         // of proxy info to all the JVMs.
@@ -2630,6 +2630,34 @@ public ProxyInfo getProxy() {
         }
     }
 
+    // Convert empty ProxyInfo's to null as null-checks are used to determine if proxies are present
+    // (e.g. if mGlobalProxy==null fall back to network-specific proxy, if network-specific
+    // proxy is null then there is no proxy in place).
+    private ProxyInfo canonicalizeProxyInfo(ProxyInfo proxy) {
+        if (proxy != null && TextUtils.isEmpty(proxy.getHost())
+                && (proxy.getPacFileUrl() == null || Uri.EMPTY.equals(proxy.getPacFileUrl()))) {
+            proxy = null;
+        }
+        return proxy;
+    }
+
+    // ProxyInfo equality function with a couple modifications over ProxyInfo.equals() to make it
+    // better for determining if a new proxy broadcast is necessary:
+    // 1. Canonicalize empty ProxyInfos to null so an empty proxy compares equal to null so as to
+    //    avoid unnecessary broadcasts.
+    // 2. Make sure all parts of the ProxyInfo's compare true, including the host when a PAC URL
+    //    is in place.  This is important so legacy PAC resolver (see com.android.proxyhandler)
+    //    changes aren't missed.  The legacy PAC resolver pretends to be a simple HTTP proxy but
+    //    actually uses the PAC to resolve; this results in ProxyInfo's with PAC URL, host and port
+    //    all set.
+    private boolean proxyInfoEqual(ProxyInfo a, ProxyInfo b) {
+        a = canonicalizeProxyInfo(a);
+        b = canonicalizeProxyInfo(b);
+        // ProxyInfo.equals() doesn't check hosts when PAC URLs are present, but we need to check
+        // hosts even when PAC URLs are present to account for the legacy PAC resolver.
+        return Objects.equals(a, b) && (a == null || Objects.equals(a.getHost(), b.getHost()));
+    }
+
     public void setGlobalProxy(ProxyInfo proxyProperties) {
         enforceConnectivityInternalPermission();
 
@@ -2747,6 +2775,20 @@ private void handleApplyDefaultProxy(ProxyInfo proxy) {
         }
     }
 
+    // If the proxy has changed from oldLp to newLp, resend proxy broadcast with default proxy.
+    // This method gets called when any network changes proxy, but the broadcast only ever contains
+    // the default proxy (even if it hasn't changed).
+    // TODO: Deprecate the broadcast extras as they aren't necessarily applicable in a multi-network
+    // world where an app might be bound to a non-default network.
+    private void updateProxy(LinkProperties newLp, LinkProperties oldLp, NetworkAgentInfo nai) {
+        ProxyInfo newProxyInfo = newLp == null ? null : newLp.getHttpProxy();
+        ProxyInfo oldProxyInfo = oldLp == null ? null : oldLp.getHttpProxy();
+
+        if (!proxyInfoEqual(newProxyInfo, oldProxyInfo)) {
+            sendProxyBroadcast(getDefaultProxy());
+        }
+    }
+
     private void handleDeprecatedGlobalHttpProxy() {
         String proxy = Settings.Global.getString(mContext.getContentResolver(),
                 Settings.Global.HTTP_PROXY);
@@ -3660,7 +3702,11 @@ private void updateLinkProperties(NetworkAgentInfo networkAgent, LinkProperties
         updateDnses(newLp, oldLp, netId, flushDns, useDefaultDns);
 
         updateClat(newLp, oldLp, networkAgent);
-        if (isDefaultNetwork(networkAgent)) handleApplyDefaultProxy(newLp.getHttpProxy());
+        if (isDefaultNetwork(networkAgent)) {
+            handleApplyDefaultProxy(newLp.getHttpProxy());
+        } else {
+            updateProxy(newLp, oldLp, networkAgent);
+        }
         // TODO - move this check to cover the whole function
         if (!Objects.equals(newLp, oldLp)) {
             notifyIfacesChanged();