Bug 1588218 - Expose DNS suffix list (Android) r=michal,snorp

Differential Revision: https://phabricator.services.mozilla.com/D51561

--HG--
extra : moz-landing-system : lando

mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoAppShell.java

@@ -66,6 +66,8 @@ import android.location.LocationListener;
 import android.location.LocationManager;
 import android.media.AudioManager;
 import android.net.ConnectivityManager;
+import android.net.LinkProperties;
+import android.net.Network;
 import android.net.NetworkInfo;
 import android.os.Build;
 import android.os.Bundle;
@@ -1231,6 +1233,27 @@ public class GeckoAppShell {
         }
     }
 
+    @WrapForJNI(calledFrom = "gecko")
+    private static String getDNSDomains() {
+        if (Build.VERSION.SDK_INT < 21) {
+            return "";
+        }
+
+        ConnectivityManager cm = (ConnectivityManager)
+            getApplicationContext().getSystemService(Context.CONNECTIVITY_SERVICE);
+        Network net = cm.getActiveNetwork();
+        if (net == null) {
+            return "";
+        }
+
+        LinkProperties lp = cm.getLinkProperties(net);
+        if (lp == null) {
+            return "";
+        }
+
+        return lp.getDomains();
+    }
+
     @WrapForJNI(calledFrom = "gecko")
     private static int[] getSystemColors() {
         // attrsAppearance[] must correspond to AndroidSystemColors structure in android/AndroidBridge.h

netwerk/system/android/nsAndroidNetworkLinkService.cpp

@@ -134,7 +134,22 @@ nsAndroidNetworkLinkService::GetNetworkID(nsACString& aNetworkID) {
 NS_IMETHODIMP
 nsAndroidNetworkLinkService::GetDnsSuffixList(
     nsTArray<nsCString>& aDnsSuffixList) {
-  return NS_ERROR_NOT_IMPLEMENTED;
+  aDnsSuffixList.Clear();
+  if (!mozilla::AndroidBridge::Bridge()) {
+    NS_WARNING("GetDnsSuffixList is not supported without a bridge connection");
+    return NS_ERROR_NOT_AVAILABLE;
+  }
+
+  auto suffixList = java::GeckoAppShell::GetDNSDomains();
+  if (!suffixList) {
+    return NS_OK;
+  }
+
+  nsAutoCString list(suffixList->ToCString());
+  for (const nsACString& suffix : list.Split(',')) {
+    aDnsSuffixList.AppendElement(suffix);
+  }
+  return NS_OK;
 }
 
 void nsAndroidNetworkLinkService::OnNetworkChanged() {