commit 5c969741ec2b464b800eb6f5970101b4b9ce6103

Author: Owen O'Malley <omalley@apache.org>
Date:   Wed Jun 23 14:37:10 2010 -0700

    HADOOP-6832. Add a static user plugin for web auth for external users.
    (omalley)
    
    +++ b/YAHOO-CHANGES.txt
    +    HADOOP-6832. Add a static user plugin for web auth for external users.
    +    (omalley)
    +


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-0.20-security-patches@1077563 13f79535-47bb-0310-9956-ffa450edef68

src/core/org/apache/hadoop/http/lib/StaticUserWebFilter.java

@@ -0,0 +1,117 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.hadoop.http.lib;
+
+import java.io.IOException;
+import java.security.Principal;
+import java.util.HashMap;
+
+import javax.servlet.FilterChain;
+import javax.servlet.FilterConfig;
+import javax.servlet.ServletException;
+import javax.servlet.ServletRequest;
+import javax.servlet.ServletResponse;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletRequestWrapper;
+
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.http.FilterContainer;
+import org.apache.hadoop.http.FilterInitializer;
+
+import javax.servlet.Filter;
+
+/**
+ * Provides a servlet filter that pretends to authenticate a fake user (Dr.Who)
+ * so that the web UI is usable for a secure cluster without authentication.
+ */
+public class StaticUserWebFilter extends FilterInitializer {
+  private static final String WEB_USERNAME = "Dr.Who";
+  private static final Principal WEB_USER = new User(WEB_USERNAME);
+
+  static class User implements Principal {
+    private final String name;
+    public User(String name) {
+      this.name = name;
+    }
+    @Override
+    public String getName() {
+      return name;
+    }
+    @Override
+    public int hashCode() {
+      return name.hashCode();
+    }
+    @Override
+    public boolean equals(Object other) {
+      if (other == this) {
+        return true;
+      } else if (other == null || other.getClass() != getClass()) {
+        return false;
+      }
+      return ((User) other).name.equals(name);
+    }
+    @Override
+    public String toString() {
+      return name;
+    }    
+  }
+
+  public static class StaticUserFilter implements Filter {
+
+    @Override
+    public void destroy() {
+      // NOTHING
+    }
+
+    @Override
+    public void doFilter(ServletRequest request, ServletResponse response,
+                         FilterChain chain
+                         ) throws IOException, ServletException {
+      HttpServletRequest httpRequest = (HttpServletRequest) request;
+      // if the user is already authenticated, don't override it
+      if (httpRequest.getRemoteUser() != null) {
+        chain.doFilter(request, response);
+      } else {
+        HttpServletRequestWrapper wrapper = 
+            new HttpServletRequestWrapper(httpRequest) {
+          @Override
+          public Principal getUserPrincipal() {
+            return WEB_USER;
+          }
+          @Override
+          public String getRemoteUser() {
+            return WEB_USERNAME;
+          }
+        };
+        chain.doFilter(wrapper, response);
+      }
+    }
+
+    @Override
+    public void init(FilterConfig conf) throws ServletException {
+      // NOTHING
+    }
+    
+  }
+
+  @Override
+  public void initFilter(FilterContainer container, Configuration conf) {
+    container.addFilter("static_user_filter", StaticUserFilter.class.getName(), 
+                        new HashMap<String,String>());
+  }
+}

src/core/org/apache/hadoop/http/lib/package.html

@@ -0,0 +1,24 @@
+<html>
+
+<!--
+   Licensed to the Apache Software Foundation (ASF) under one or more
+   contributor license agreements.  See the NOTICE file distributed with
+   this work for additional information regarding copyright ownership.
+   The ASF licenses this file to You under the Apache License, Version 2.0
+   (the "License"); you may not use this file except in compliance with
+   the License.  You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+-->
+
+<body>
+</body>
+This package provides user-selectable (via configuration) classes that add
+functionality to the web UI.
+</html>