From 3e2d5da12c3bc426df346554d9d53cf9b6f09c1a Mon Sep 17 00:00:00 2001
From: Lukasz Lenart <lukasz.lenart@gmail.com>
Date: Tue, 20 Oct 2015 08:16:41 +0200
Subject: [PATCH] WW-4526 Checks if passed in scheme param is valid

---
 .../apache/struts2/views/util/DefaultUrlHelper.java   | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/core/src/main/java/org/apache/struts2/views/util/DefaultUrlHelper.java b/core/src/main/java/org/apache/struts2/views/util/DefaultUrlHelper.java
index 460c13830..4d20ee293 100644
--- a/core/src/main/java/org/apache/struts2/views/util/DefaultUrlHelper.java
+++ b/core/src/main/java/org/apache/struts2/views/util/DefaultUrlHelper.java
@@ -85,12 +85,17 @@ public class DefaultUrlHelper implements UrlHelper {
     	return buildUrl(action, request, response, params, scheme, includeContext, encodeResult, forceAddSchemeHostAndPort, true);
     }
 
-    public String buildUrl(String action, HttpServletRequest request, HttpServletResponse response, Map<String, Object> params, String scheme,
+    public String buildUrl(String action, HttpServletRequest request, HttpServletResponse response, Map<String, Object> params, String urlScheme,
                            boolean includeContext, boolean encodeResult, boolean forceAddSchemeHostAndPort, boolean escapeAmp) {
 
         StringBuilder link = new StringBuilder();
         boolean changedScheme = false;
 
+        String scheme = null;
+        if (isValidScheme(urlScheme)) {
+            scheme = urlScheme;
+        }
+
         // only append scheme if it is different to the current scheme *OR*
         // if we explicity want it to be appended by having forceAddSchemeHostAndPort = true
         if (forceAddSchemeHostAndPort) {
@@ -241,6 +246,10 @@ public class DefaultUrlHelper implements UrlHelper {
         }
     }
 
+    protected boolean isValidScheme(String scheme) {
+        return HTTP_PROTOCOL.equals(scheme) || HTTPS_PROTOCOL.equals(scheme);
+    }
+
     private String buildParameterSubstring(String name, String value) {
         StringBuilder builder = new StringBuilder();
         builder.append(encode(name));