001    /*
002     * Copyright (C) 2003-2009 eXo Platform SAS.
003     *
004     * This is free software; you can redistribute it and/or modify it
005     * under the terms of the GNU Lesser General Public License as
006     * published by the Free Software Foundation; either version 2.1 of
007     * the License, or (at your option) any later version.
008     *
009     * This software is distributed in the hope that it will be useful,
010     * but WITHOUT ANY WARRANTY; without even the implied warranty of
011     * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
012     * Lesser General Public License for more details.
013     *
014     * You should have received a copy of the GNU Lesser General Public
015     * License along with this software; if not, write to the Free
016     * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
017     * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
018     */
019    package org.crsh.ssh.term;
020    
021    import org.apache.sshd.SshServer;
022    import org.apache.sshd.common.Session;
023    import org.apache.sshd.server.PasswordAuthenticator;
024    import org.apache.sshd.server.session.ServerSession;
025    import org.crsh.plugin.PluginContext;
026    import org.crsh.auth.AuthenticationPlugin;
027    import org.crsh.ssh.term.scp.SCPCommandFactory;
028    import org.crsh.term.TermLifeCycle;
029    import org.crsh.term.spi.TermIOHandler;
030    import org.slf4j.Logger;
031    import org.slf4j.LoggerFactory;
032    
033    import java.net.URL;
034    
035    /**
036     * @author <a href="mailto:julien.viet@exoplatform.com">Julien Viet</a>
037     * @version $Revision$
038     */
039    public class SSHLifeCycle extends TermLifeCycle {
040    
041      /** . */
042      public static final Session.AttributeKey<String> USERNAME = new Session.AttributeKey<java.lang.String>();
043    
044      /** . */
045      public static final Session.AttributeKey<String> PASSWORD = new Session.AttributeKey<java.lang.String>();
046    
047      /** . */
048      private final Logger log = LoggerFactory.getLogger(SSHLifeCycle.class);
049    
050      /** . */
051      private SshServer server;
052    
053      /** . */
054      private int port;
055    
056      /** . */
057      private URL keyURL;
058    
059      /** . */
060      private String authentication;
061    
062      public SSHLifeCycle(PluginContext context) {
063        super(context);
064      }
065    
066      public int getPort() {
067        return port;
068      }
069    
070      public void setPort(int port) {
071        this.port = port;
072      }
073    
074      public URL getKeyURL() {
075        return keyURL;
076      }
077    
078      public void setKeyURL(URL keyURL) {
079        this.keyURL = keyURL;
080      }
081    
082      public String getAuthentication() {
083        return authentication;
084      }
085    
086      public void setAuthentication(String authentication) {
087        this.authentication = authentication;
088      }
089    
090      @Override
091      protected void doInit() {
092        try {
093    
094          //
095          TermIOHandler handler = getHandler();
096    
097          //
098          SshServer server = SshServer.setUpDefaultServer();
099          server.setPort(port);
100          server.setShellFactory(new CRaSHCommandFactory(handler));
101          server.setCommandFactory(new SCPCommandFactory(getContext()));
102          server.setKeyPairProvider(new URLKeyPairProvider(keyURL));
103    
104          // We never authenticate by default
105          AuthenticationPlugin plugin = new AuthenticationPlugin() {
106            public String getName() {
107              return "null";
108            }
109            public boolean authenticate(String username, String password) throws Exception {
110              return false;
111            }
112          };
113    
114          // Lookup for an authentication plugin
115          if (authentication != null) {
116            for (AuthenticationPlugin authenticationPlugin : getContext().getPlugins(AuthenticationPlugin.class)) {
117              if (authentication.equals(authenticationPlugin.getName())) {
118                plugin = authenticationPlugin;
119                break;
120              }
121            }
122          }
123    
124          //
125          final AuthenticationPlugin authPlugin = plugin;
126    
127          //
128          server.setPasswordAuthenticator(new PasswordAuthenticator() {
129            public boolean authenticate(String _username, String _password, ServerSession session) {
130              boolean auth;
131              if (authPlugin != null)
132              {
133                try {
134                  log.debug("Using authentication plugin " + authPlugin + " to authenticate user " + _username);
135                  auth = authPlugin.authenticate(_username, _password);
136                } catch (Exception e) {
137                  log.error("Exception authenticating user " + _username + " in authentication plugin: " + authPlugin, e);
138                  return false;
139                }
140              }
141              else 
142              {
143                // Say ok as this will be used later for performing an other kind of authentication
144                auth = true;
145              }
146    
147              // We store username and password in session for later reuse
148              session.setAttribute(USERNAME, _username);
149              session.setAttribute(PASSWORD, _password);
150    
151              //
152              return auth;
153            }
154          });
155    
156          //
157          log.info("About to start CRaSSHD");
158          server.start();
159          log.info("CRaSSHD started on port " + port);
160    
161          //
162          this.server = server;
163        }
164        catch (Throwable e) {
165          log.error("Could not start CRaSSHD", e);
166        }
167      }
168    
169      @Override
170      protected void doDestroy() {
171        if (server != null) {
172          try {
173            server.stop();
174          }
175          catch (InterruptedException e) {
176            log.debug("Got an interruption when stopping server", e);
177          }
178        }
179      }
180    }