SEC-1078: Missed commit of default strategy class.

web/src/main/java/org/springframework/security/web/authentication/preauth/websphere/DefaultWASUsernameAndGroupsExtractor.java

@@ -0,0 +1,205 @@
+package org.springframework.security.web.authentication.preauth.websphere;
+
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.List;
+
+import javax.naming.Context;
+import javax.naming.InitialContext;
+import javax.naming.NamingException;
+import javax.rmi.PortableRemoteObject;
+import javax.security.auth.Subject;
+
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+
+/**
+ * WebSphere Security helper class to allow retrieval of the current username and groups.
+ * <p>
+ * See Spring Security Jira SEC-477.
+ *
+ * @author Ruud Senden
+ * @author Stephane Manciot
+ * @since 2.0
+ */
+final class DefaultWASUsernameAndGroupsExtractor implements WASUsernameAndGroupsExtractor {
+    private static final Log logger = LogFactory.getLog(DefaultWASUsernameAndGroupsExtractor.class);
+
+    private static final String USER_REGISTRY = "UserRegistry";
+
+    private static Method getRunAsSubject = null;
+
+    private static Method getGroupsForUser = null;
+
+    private static Method getSecurityName = null;
+
+    // SEC-803
+    private static Class<?> wsCredentialClass = null;
+
+    public final List<String> getGroupsForCurrentUser() {
+        return getWebSphereGroups(getRunAsSubject());
+    }
+
+    public final String getCurrentUserName() {
+        return getSecurityName(getRunAsSubject());
+    }
+
+    /**
+     * Get the security name for the given subject.
+     *
+     * @param subject
+     *            The subject for which to retrieve the security name
+     * @return String the security name for the given subject
+     */
+    private static final String getSecurityName(final Subject subject) {
+        if (logger.isDebugEnabled()) {
+            logger.debug("Determining Websphere security name for subject " + subject);
+        }
+        String userSecurityName = null;
+        if (subject != null) {
+            // SEC-803
+            Object credential = subject.getPublicCredentials(getWSCredentialClass()).iterator().next();
+            if (credential != null) {
+                userSecurityName = (String)invokeMethod(getSecurityNameMethod(),credential,null);
+            }
+        }
+        if (logger.isDebugEnabled()) {
+            logger.debug("Websphere security name is " + userSecurityName + " for subject " + subject);
+        }
+        return userSecurityName;
+    }
+
+    /**
+     * Get the current RunAs subject.
+     *
+     * @return Subject the current RunAs subject
+     */
+    private static final Subject getRunAsSubject() {
+        logger.debug("Retrieving WebSphere RunAs subject");
+        // get Subject: WSSubject.getCallerSubject ();
+        return (Subject) invokeMethod(getRunAsSubjectMethod(), null, new Object[] {});
+    }
+
+    /**
+     * Get the WebSphere group names for the given subject.
+     *
+     * @param subject
+     *            The subject for which to retrieve the WebSphere group names
+     * @return the WebSphere group names for the given subject
+     */
+    private static final List<String> getWebSphereGroups(final Subject subject) {
+        return getWebSphereGroups(getSecurityName(subject));
+    }
+
+    /**
+     * Get the WebSphere group names for the given security name.
+     *
+     * @param securityName
+     *            The security name for which to retrieve the WebSphere group names
+     * @return the WebSphere group names for the given security name
+     */
+    @SuppressWarnings("unchecked")
+    private static final List<String> getWebSphereGroups(final String securityName) {
+        Context ic = null;
+        try {
+            // TODO: Cache UserRegistry object
+            ic = new InitialContext();
+            Object objRef = ic.lookup(USER_REGISTRY);
+            Object userReg = PortableRemoteObject.narrow(objRef, Class.forName ("com.ibm.websphere.security.UserRegistry"));
+            if (logger.isDebugEnabled()) {
+                logger.debug("Determining WebSphere groups for user " + securityName + " using WebSphere UserRegistry " + userReg);
+            }
+            final Collection groups = (Collection) invokeMethod(getGroupsForUserMethod(), userReg, new Object[]{ securityName });
+            if (logger.isDebugEnabled()) {
+                logger.debug("Groups for user " + securityName + ": " + groups.toString());
+            }
+
+            return new ArrayList(groups);
+        } catch (Exception e) {
+            logger.error("Exception occured while looking up groups for user", e);
+            throw new RuntimeException("Exception occured while looking up groups for user", e);
+        } finally {
+            try {
+                ic.close();
+            } catch (NamingException e) {
+                logger.debug("Exception occured while closing context", e);
+            }
+        }
+    }
+
+    private static final Object invokeMethod(Method method, Object instance, Object[] args)
+    {
+        try {
+            return method.invoke(instance,args);
+        } catch (IllegalArgumentException e) {
+            logger.error("Error while invoking method "+method.getClass().getName()+"."+method.getName()+"("+ Arrays.asList(args)+")",e);
+            throw new RuntimeException("Error while invoking method "+method.getClass().getName()+"."+method.getName()+"("+Arrays.asList(args)+")",e);
+        } catch (IllegalAccessException e) {
+            logger.error("Error while invoking method "+method.getClass().getName()+"."+method.getName()+"("+Arrays.asList(args)+")",e);
+            throw new RuntimeException("Error while invoking method "+method.getClass().getName()+"."+method.getName()+"("+Arrays.asList(args)+")",e);
+        } catch (InvocationTargetException e) {
+            logger.error("Error while invoking method "+method.getClass().getName()+"."+method.getName()+"("+Arrays.asList(args)+")",e);
+            throw new RuntimeException("Error while invoking method "+method.getClass().getName()+"."+method.getName()+"("+Arrays.asList(args)+")",e);
+        }
+    }
+
+    private static final Method getMethod(String className, String methodName, String[] parameterTypeNames) {
+        try {
+            Class<?> c = Class.forName(className);
+            final int len = parameterTypeNames.length;
+            Class<?>[] parameterTypes = new Class[len];
+            for (int i = 0; i < len; i++) {
+                parameterTypes[i] = Class.forName(parameterTypeNames[i]);
+            }
+            return c.getDeclaredMethod(methodName, parameterTypes);
+        } catch (ClassNotFoundException e) {
+            logger.error("Required class"+className+" not found");
+            throw new RuntimeException("Required class"+className+" not found",e);
+        } catch (NoSuchMethodException e) {
+            logger.error("Required method "+methodName+" with parameter types ("+ Arrays.asList(parameterTypeNames) +") not found on class "+className);
+            throw new RuntimeException("Required class"+className+" not found",e);
+        }
+    }
+
+    private static final Method getRunAsSubjectMethod() {
+        if (getRunAsSubject == null) {
+            getRunAsSubject = getMethod("com.ibm.websphere.security.auth.WSSubject", "getRunAsSubject", new String[] {});
+        }
+        return getRunAsSubject;
+    }
+
+    private static final Method getGroupsForUserMethod() {
+        if (getGroupsForUser == null) {
+            getGroupsForUser = getMethod("com.ibm.websphere.security.UserRegistry", "getGroupsForUser", new String[] { "java.lang.String" });
+        }
+        return getGroupsForUser;
+    }
+
+    private static final Method getSecurityNameMethod() {
+        if (getSecurityName == null) {
+            getSecurityName = getMethod("com.ibm.websphere.security.cred.WSCredential", "getSecurityName", new String[] {});
+        }
+        return getSecurityName;
+    }
+
+    // SEC-803
+    private static final Class<?> getWSCredentialClass() {
+        if (wsCredentialClass == null) {
+            wsCredentialClass = getClass("com.ibm.websphere.security.cred.WSCredential");
+        }
+        return wsCredentialClass;
+    }
+
+    private static final Class<?> getClass(String className) {
+        try {
+            return Class.forName(className);
+        } catch (ClassNotFoundException e) {
+            logger.error("Required class " + className + " not found");
+            throw new RuntimeException("Required class " + className + " not found",e);
+        }
+    }
+
+}