diff --git a/core/src/main/java/hudson/Functions.java b/core/src/main/java/hudson/Functions.java
index 5e118478c8..03c6d937f7 100644
--- a/core/src/main/java/hudson/Functions.java
+++ b/core/src/main/java/hudson/Functions.java
@@ -32,6 +32,7 @@ import org.kohsuke.stapler.Ancestor;
 import org.kohsuke.stapler.Stapler;
 import org.kohsuke.stapler.StaplerRequest;
 import org.kohsuke.stapler.StaplerResponse;
+import org.acegisecurity.providers.anonymous.AnonymousAuthenticationToken;
 
 import javax.servlet.ServletException;
 import javax.servlet.http.Cookie;
@@ -723,4 +724,11 @@ public class Functions {
     }
 
     private static final Pattern LINE_END = Pattern.compile("\r?\n");
+
+    /**
+     * Checks if the current user is anonymous.
+     */
+    public static boolean isAnonymous() {
+        return Hudson.getAuthentication() instanceof AnonymousAuthenticationToken;
+    }
 }
diff --git a/core/src/main/java/hudson/model/Hudson.java b/core/src/main/java/hudson/model/Hudson.java
index fc286489fc..0ab6322c51 100644
--- a/core/src/main/java/hudson/model/Hudson.java
+++ b/core/src/main/java/hudson/model/Hudson.java
@@ -62,6 +62,7 @@ import hudson.widgets.Widget;
 import net.sf.json.JSONObject;
 import org.acegisecurity.context.SecurityContextHolder;
 import org.acegisecurity.ui.AbstractProcessingFilter;
+import org.acegisecurity.Authentication;
 import org.apache.commons.fileupload.FileItem;
 import org.apache.commons.fileupload.disk.DiskFileItemFactory;
 import org.apache.commons.fileupload.servlet.ServletFileUpload;
@@ -1798,8 +1799,7 @@ public final class Hudson extends View implements ItemGroup<TopLevelItem>, Node
         if(!Hudson.adminCheck(req,rsp))
             return;
         LOGGER.severe(String.format("Shutting down VM as requested by {0} from {1}",
-                SecurityContextHolder.getContext().getAuthentication(),
-                req.getRemoteAddr()));
+                getAuthentication(), req.getRemoteAddr()));
         rsp.setStatus(HttpServletResponse.SC_OK);
         rsp.setContentType("text/plain");
         PrintWriter w = rsp.getWriter();
@@ -1809,6 +1809,14 @@ public final class Hudson extends View implements ItemGroup<TopLevelItem>, Node
         System.exit(0);
     }
 
+    /**
+     * Gets the {@link Authentication} object that represents the user
+     * associated with the current request.
+     */
+    public static Authentication getAuthentication() {
+        return SecurityContextHolder.getContext().getAuthentication();
+    }
+
     /**
      * Configure the logging level.
      */