YARN-7338. Support same origin policy for cross site scripting prevention. (Sunil G via wangda)

(cherry picked from commit 298b174f663a06e67098f7b5cd645769c1a98a80)

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/webapp/WebApps.java

@@ -401,6 +401,7 @@ public class WebApps {
       WebApp webApp = build(webapp);
       HttpServer2 httpServer = webApp.httpServer();
       if (ui2Context != null) {
+        addFiltersForNewContext(ui2Context);
         httpServer.addHandlerAtFront(ui2Context);
       }
       try {
@@ -413,6 +414,27 @@ public class WebApps {
       return webApp;
     }
 
+    private void addFiltersForNewContext(WebAppContext ui2Context) {
+      Map<String, String> params = getConfigParameters(csrfConfigPrefix);
+
+      if (hasCSRFEnabled(params)) {
+        LOG.info("CSRF Protection has been enabled for the {} application. "
+            + "Please ensure that there is an authentication mechanism "
+            + "enabled (kerberos, custom, etc).", name);
+        String restCsrfClassName = RestCsrfPreventionFilter.class.getName();
+        HttpServer2.defineFilter(ui2Context, restCsrfClassName,
+            restCsrfClassName, params, new String[]{"/*"});
+      }
+
+      params = getConfigParameters(xfsConfigPrefix);
+
+      if (hasXFSEnabled()) {
+        String xfsClassName = XFrameOptionsFilter.class.getName();
+        HttpServer2.defineFilter(ui2Context, xfsClassName, xfsClassName, params,
+            new String[]{"/*"});
+      }
+    }
+
     private String inferHostClass() {
       String thisClass = this.getClass().getName();
       Throwable t = new Throwable();