content: /**
   * 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.activemq.jaas;
  
  import java.io.IOException;
  import java.net.URI;
  import java.net.URISyntaxException;
  import java.security.Principal;
  import java.text.MessageFormat;
  import java.util.*;
  
  import javax.naming.*;
  import javax.naming.directory.Attribute;
  import javax.naming.directory.Attributes;
  import javax.naming.directory.DirContext;
  import javax.naming.directory.InitialDirContext;
  import javax.naming.directory.SearchControls;
  import javax.naming.directory.SearchResult;
  import javax.security.auth.Subject;
  import javax.security.auth.callback.Callback;
  import javax.security.auth.callback.CallbackHandler;
  import javax.security.auth.callback.NameCallback;
  import javax.security.auth.callback.PasswordCallback;
  import javax.security.auth.callback.UnsupportedCallbackException;
  import javax.security.auth.login.FailedLoginException;
  import javax.security.auth.login.LoginException;
  import javax.security.auth.spi.LoginModule;
  
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  /**
   * @version $Rev: $ $Date: $
   */
  public class LDAPLoginModule implements LoginModule {
  
      private static final String INITIAL_CONTEXT_FACTORY = "initialContextFactory";
      private static final String CONNECTION_URL = "connectionURL";
      private static final String CONNECTION_USERNAME = "connectionUsername";
      private static final String CONNECTION_PASSWORD = "connectionPassword";
      private static final String CONNECTION_PROTOCOL = "connectionProtocol";
      private static final String AUTHENTICATION = "authentication";
      private static final String USER_BASE = "userBase";
      private static final String USER_SEARCH_MATCHING = "userSearchMatching";
      private static final String USER_SEARCH_SUBTREE = "userSearchSubtree";
      private static final String ROLE_BASE = "roleBase";
      private static final String ROLE_NAME = "roleName";
      private static final String ROLE_SEARCH_MATCHING = "roleSearchMatching";
      private static final String ROLE_SEARCH_SUBTREE = "roleSearchSubtree";
      private static final String USER_ROLE_NAME = "userRoleName";
      private static final String EXPAND_ROLES = "expandRoles";
      private static final String EXPAND_ROLES_MATCHING = "expandRolesMatching";
  
      private static Logger log = LoggerFactory.getLogger(LDAPLoginModule.class);
  
      protected DirContext context;
  
      private Subject subject;
      private CallbackHandler handler;
      private LDAPLoginProperty [] config;
      private Principal user;
      private Set<GroupPrincipal> groups = new HashSet<>();
  
      /** the authentication status*/
      private boolean succeeded = false;
      private boolean commitSucceeded = false;
  
      @Override
      public void initialize(Subject subject, CallbackHandler callbackHandler, Map sharedState, Map options) {
          this.subject = subject;
          this.handler = callbackHandler;
  
          config = new LDAPLoginProperty [] {
          		new LDAPLoginProperty (INITIAL_CONTEXT_FACTORY, (String)options.get(INITIAL_CONTEXT_FACTORY)),
          		new LDAPLoginProperty (CONNECTION_URL, (String)options.get(CONNECTION_URL)),
          		new LDAPLoginProperty (CONNECTION_USERNAME, (String)options.get(CONNECTION_USERNAME)),
          		new LDAPLoginProperty (CONNECTION_PASSWORD, (String)options.get(CONNECTION_PASSWORD)),
          		new LDAPLoginProperty (CONNECTION_PROTOCOL, (String)options.get(CONNECTION_PROTOCOL)),
          		new LDAPLoginProperty (AUTHENTICATION, (String)options.get(AUTHENTICATION)),
          		new LDAPLoginProperty (USER_BASE, (String)options.get(USER_BASE)),
          		new LDAPLoginProperty (USER_SEARCH_MATCHING, (String)options.get(USER_SEARCH_MATCHING)),
          		new LDAPLoginProperty (USER_SEARCH_SUBTREE, (String)options.get(USER_SEARCH_SUBTREE)),
          		new LDAPLoginProperty (ROLE_BASE, (String)options.get(ROLE_BASE)),
          		new LDAPLoginProperty (ROLE_NAME, (String)options.get(ROLE_NAME)),
          		new LDAPLoginProperty (ROLE_SEARCH_MATCHING, (String)options.get(ROLE_SEARCH_MATCHING)),
          		new LDAPLoginProperty (ROLE_SEARCH_SUBTREE, (String)options.get(ROLE_SEARCH_SUBTREE)),
          		new LDAPLoginProperty (USER_ROLE_NAME, (String)options.get(USER_ROLE_NAME)),
                  new LDAPLoginProperty (EXPAND_ROLES, (String) options.get(EXPAND_ROLES)),
                  new LDAPLoginProperty (EXPAND_ROLES_MATCHING, (String) options.get(EXPAND_ROLES_MATCHING)),
  
          };
      }
  
      @Override
      public boolean login() throws LoginException {
  
          Callback[] callbacks = new Callback[2];
  
          callbacks[0] = new NameCallback("User name");
          callbacks[1] = new PasswordCallback("Password", false);
          try {
              handler.handle(callbacks);
          } catch (IOException | UnsupportedCallbackException ioe) {
              throw (LoginException)new LoginException().initCause(ioe);
          }
  
          String password;
  
          String username = ((NameCallback)callbacks[0]).getName();
          if (username == null)
          	return false;
  
          if (((PasswordCallback)callbacks[1]).getPassword() != null)
          	password = new String(((PasswordCallback)callbacks[1]).getPassword());
          else
          	password="";
  
          // authenticate will throw LoginException
          // in case of failed authentication
          authenticate(username, password);
  
          user = new UserPrincipal(username);
          succeeded = true;
          return true;
      }
  
      @Override
      public boolean logout() throws LoginException {
          subject.getPrincipals().remove(user);
          subject.getPrincipals().removeAll(groups);
  
          user = null;
          groups.clear();
  
          succeeded = false;
          commitSucceeded = false;
          return true;
      }
  
      @Override
      public boolean commit() throws LoginException {
          if (!succeeded) {
              user = null;
              groups.clear();
              return false;
          }
  
          Set<Principal> principals = subject.getPrincipals();
          principals.add(user);
          principals.addAll(groups);
  
          commitSucceeded = true;
          return true;
      }
  
      @Override
      public boolean abort() throws LoginException {
          if (!succeeded) {
              return false;
          } else if (commitSucceeded) {
              // we succeeded, but another required module failed
              logout();
          } else {
              // our commit failed
              user = null;
              groups.clear();
              succeeded = false;
          }
          return true;
      }
  
      protected void closeContext() {
          if (context == null) {
              return;
          }
          try {
              context.close();
          } catch (Exception e) {
              log.error(e.toString());
          } finally {
              context = null;
          }
      }
  
      protected boolean authenticate(String username, String password) throws LoginException {
  
          MessageFormat userSearchMatchingFormat;
          boolean userSearchSubtreeBool;
  
          if (log.isDebugEnabled()) {
              log.debug("Create the LDAP initial context.");
          }
          try {
              openContext();
          } catch (NamingException ne) {
              FailedLoginException ex = new FailedLoginException("Error opening LDAP connection");
              ex.initCause(ne);
              throw ex;
          }
  
          if (!isLoginPropertySet(USER_SEARCH_MATCHING))
          	return false;
  
          userSearchMatchingFormat = new MessageFormat(getLDAPPropertyValue(USER_SEARCH_MATCHING));
          userSearchSubtreeBool = Boolean.valueOf(getLDAPPropertyValue(USER_SEARCH_SUBTREE));
  
          try {
  
              String filter = userSearchMatchingFormat.format(new String[] {
                  doRFC2254Encoding(username)
              });
              SearchControls constraints = new SearchControls();
              if (userSearchSubtreeBool) {
                  constraints.setSearchScope(SearchControls.SUBTREE_SCOPE);
              } else {
                  constraints.setSearchScope(SearchControls.ONELEVEL_SCOPE);
              }
  
              // setup attributes
              List<String> list = new ArrayList<>();
              if (isLoginPropertySet(USER_ROLE_NAME)) {
                  list.add(getLDAPPropertyValue(USER_ROLE_NAME));
              }
              String[] attribs = new String[list.size()];
              list.toArray(attribs);
              constraints.setReturningAttributes(attribs);
  
              if (log.isDebugEnabled()) {
                  log.debug("Get the user DN.");
                  log.debug("Looking for the user in LDAP with ");
                  log.debug("  base DN: " + getLDAPPropertyValue(USER_BASE));
                  log.debug("  filter: " + filter);
              }
  
              NamingEnumeration<SearchResult> results = context.search(getLDAPPropertyValue(USER_BASE), filter, constraints);
  
              if (results == null || !results.hasMore()) {
                  log.warn("User " + username + " not found in LDAP.");
                  throw new FailedLoginException("User " + username + " not found in LDAP.");
              }
  
              SearchResult result = results.next();
  
              if (results.hasMore()) {
                  // ignore for now
              }
  
              String dn;
              if (result.isRelative()) {
                  log.debug("LDAP returned a relative name: {}", result.getName());
  
                  NameParser parser = context.getNameParser("");
                  Name contextName = parser.parse(context.getNameInNamespace());
                  Name baseName = parser.parse(getLDAPPropertyValue(USER_BASE));
                  Name entryName = parser.parse(result.getName());
                  Name name = contextName.addAll(baseName);
                  name = name.addAll(entryName);
                  dn = name.toString();
              } else {
                  log.debug("LDAP returned an absolute name: {}", result.getName());
  
                  try {
                      URI uri = new URI(result.getName());
                      String path = uri.getPath();
  
                      if (path.startsWith("/")) {
                          dn = path.substring(1);
                      } else {
                          dn = path;
                      }
                  } catch (URISyntaxException e) {
                      closeContext();
                      FailedLoginException ex = new FailedLoginException("Error parsing absolute name as URI.");
                      ex.initCause(e);
                      throw ex;
                  }
              }
  
              if (log.isDebugEnabled()) {
                  log.debug("Using DN [" + dn + "] for binding.");
              }
  
              Attributes attrs = result.getAttributes();
              if (attrs == null) {
                  throw new FailedLoginException("User found, but LDAP entry malformed: " + username);
              }
              List<String> roles = null;
              if (isLoginPropertySet(USER_ROLE_NAME)) {
                  roles = addAttributeValues(getLDAPPropertyValue(USER_ROLE_NAME), attrs, roles);
              }
  
              // check the credentials by binding to server
              if (bindUser(context, dn, password)) {
                  // if authenticated add more roles
                  roles = getRoles(context, dn, username, roles);
                  if (log.isDebugEnabled()) {
                      log.debug("Roles " + roles + " for user " + username);
                  }
                  for (int i = 0; i < roles.size(); i++) {
                      groups.add(new GroupPrincipal(roles.get(i)));
                  }
              } else {
                  throw new FailedLoginException("Password does not match for user: " + username);
              }
          } catch (CommunicationException e) {
              FailedLoginException ex = new FailedLoginException("Error contacting LDAP");
              ex.initCause(e);
              throw ex;
          } catch (NamingException e) {
              FailedLoginException ex = new FailedLoginException("Error contacting LDAP");
              ex.initCause(e);
              throw ex;
          } finally {
              closeContext();
          }
          return true;
      }
  
      protected List<String> getRoles(DirContext context, String dn, String username, List<String> currentRoles) throws NamingException {
          List<String> list = currentRoles;
          MessageFormat roleSearchMatchingFormat;
          boolean roleSearchSubtreeBool;
          boolean expandRolesBool;
          roleSearchMatchingFormat = new MessageFormat(getLDAPPropertyValue(ROLE_SEARCH_MATCHING));
          roleSearchSubtreeBool = Boolean.parseBoolean(getLDAPPropertyValue(ROLE_SEARCH_SUBTREE));
          expandRolesBool = Boolean.parseBoolean(getLDAPPropertyValue(EXPAND_ROLES));
  
          if (list == null) {
              list = new ArrayList<>();
          }
          if (!isLoginPropertySet(ROLE_NAME)) {
              return list;
          }
          String filter = roleSearchMatchingFormat.format(new String[] {
              doRFC2254Encoding(dn), doRFC2254Encoding(username)
          });
  
          SearchControls constraints = new SearchControls();
          if (roleSearchSubtreeBool) {
              constraints.setSearchScope(SearchControls.SUBTREE_SCOPE);
          } else {
              constraints.setSearchScope(SearchControls.ONELEVEL_SCOPE);
          }
          if (log.isDebugEnabled()) {
              log.debug("Get user roles.");
              log.debug("Looking for the user roles in LDAP with ");
              log.debug("  base DN: " + getLDAPPropertyValue(ROLE_BASE));
              log.debug("  filter: " + filter);
          }
          HashSet<String> haveSeenNames = new HashSet<>();
          Queue<String> pendingNameExpansion = new LinkedList<>();
          NamingEnumeration<SearchResult> results = context.search(getLDAPPropertyValue(ROLE_BASE), filter, constraints);
          while (results.hasMore()) {
              SearchResult result = results.next();
              Attributes attrs = result.getAttributes();
              if (expandRolesBool) {
                  haveSeenNames.add(result.getNameInNamespace());
                  pendingNameExpansion.add(result.getNameInNamespace());
              }
              if (attrs == null) {
                  continue;
              }
              list = addAttributeValues(getLDAPPropertyValue(ROLE_NAME), attrs, list);
          }
          if (expandRolesBool) {
              MessageFormat expandRolesMatchingFormat = new MessageFormat(getLDAPPropertyValue(EXPAND_ROLES_MATCHING));
              while (!pendingNameExpansion.isEmpty()) {
                  String name = pendingNameExpansion.remove();
                  filter = expandRolesMatchingFormat.format(new String[]{name});
                  results = context.search(getLDAPPropertyValue(ROLE_BASE), filter, constraints);
                  while (results.hasMore()) {
                      SearchResult result = results.next();
                      name = result.getNameInNamespace();
                      if (!haveSeenNames.contains(name)) {
                          Attributes attrs = result.getAttributes();
                          list = addAttributeValues(getLDAPPropertyValue(ROLE_NAME), attrs, list);
                          haveSeenNames.add(name);
                          pendingNameExpansion.add(name);
                      }
                  }
              }
          }
          return list;
      }
  
      protected String doRFC2254Encoding(String inputString) {
          StringBuilder buf = new StringBuilder(inputString.length());
          for (int i = 0; i < inputString.length(); i++) {
              char c = inputString.charAt(i);
              switch (c) {
              case '\\':
                  buf.append("\\5c");
                  break;
              case '*':
                  buf.append("\\2a");
                  break;
              case '(':
                  buf.append("\\28");
                  break;
              case ')':
                  buf.append("\\29");
                  break;
              case '\0':
                  buf.append("\\00");
                  break;
              default:
                  buf.append(c);
                  break;
              }
          }
          return buf.toString();
      }
  
      protected boolean bindUser(DirContext context, String dn, String password) throws NamingException {
          boolean isValid = false;
          if (log.isDebugEnabled()) {
              log.debug("Binding the user.");
          }
          context.addToEnvironment(Context.SECURITY_AUTHENTICATION, "simple");
          context.addToEnvironment(Context.SECURITY_PRINCIPAL, dn);
          context.addToEnvironment(Context.SECURITY_CREDENTIALS, password);
          try {
              context.getAttributes("", null);
              isValid = true;
              if (log.isDebugEnabled()) {
                  log.debug("User " + dn + " successfully bound.");
              }
          } catch (AuthenticationException e) {
              if (log.isDebugEnabled()) {
                  log.debug("Authentication failed for dn=" + dn);
              }
          }
  
          if (isLoginPropertySet(CONNECTION_USERNAME)) {
              context.addToEnvironment(Context.SECURITY_PRINCIPAL, getLDAPPropertyValue(CONNECTION_USERNAME));
          } else {
              context.removeFromEnvironment(Context.SECURITY_PRINCIPAL);
          }
          if (isLoginPropertySet(CONNECTION_PASSWORD)) {
              context.addToEnvironment(Context.SECURITY_CREDENTIALS, getLDAPPropertyValue(CONNECTION_PASSWORD));
          } else {
              context.removeFromEnvironment(Context.SECURITY_CREDENTIALS);
          }
          context.addToEnvironment(Context.SECURITY_AUTHENTICATION, getLDAPPropertyValue(AUTHENTICATION));
          return isValid;
      }
  
      private List<String> addAttributeValues(String attrId, Attributes attrs, List<String> values) throws NamingException {
  
          if (attrId == null || attrs == null) {
              return values;
          }
          if (values == null) {
              values = new ArrayList<>();
          }
          Attribute attr = attrs.get(attrId);
          if (attr == null) {
              return values;
          }
          NamingEnumeration<?> e = attr.getAll();
          while (e.hasMore()) {
              String value = (String)e.next();
              values.add(value);
          }
          return values;
      }
  
      protected void openContext() throws NamingException {
          if (context != null) {
              return;
          }
          try {
              Hashtable<String, String> env = new Hashtable<>();
              env.put(Context.INITIAL_CONTEXT_FACTORY, getLDAPPropertyValue(INITIAL_CONTEXT_FACTORY));
              if (isLoginPropertySet(CONNECTION_USERNAME)) {
                  env.put(Context.SECURITY_PRINCIPAL, getLDAPPropertyValue(CONNECTION_USERNAME));
              } else {
                  throw new NamingException("Empty username is not allowed");
              }
  
              if (isLoginPropertySet(CONNECTION_PASSWORD)) {
                  env.put(Context.SECURITY_CREDENTIALS, getLDAPPropertyValue(CONNECTION_PASSWORD));
              } else {
                  throw new NamingException("Empty password is not allowed");
              }
              env.put(Context.SECURITY_PROTOCOL, getLDAPPropertyValue(CONNECTION_PROTOCOL));
              env.put(Context.PROVIDER_URL, getLDAPPropertyValue(CONNECTION_URL));
              env.put(Context.SECURITY_AUTHENTICATION, getLDAPPropertyValue(AUTHENTICATION));
              context = new InitialDirContext(env);
  
          } catch (NamingException e) {
              closeContext();
              log.error(e.toString());
              throw e;
          }
      }
  
      private String getLDAPPropertyValue (String propertyName){
          for (LDAPLoginProperty ldapLoginProperty : config)
              if (ldapLoginProperty.getPropertyName().equals(propertyName))
                  return ldapLoginProperty.getPropertyValue();
      	return null;
      }
  
      private boolean isLoginPropertySet(String propertyName) {
          for (LDAPLoginProperty ldapLoginProperty : config) {
              if (ldapLoginProperty.getPropertyName().equals(propertyName) && (ldapLoginProperty.getPropertyValue() != null && !"".equals(ldapLoginProperty.getPropertyValue())))
                  return true;
          }
      	return false;
      }
  
  }
  