Field Detail

• authentication

  protected AuthenticationProtocolClient authentication

  The SSH Authentication protocol implementation for this SSH client. The SSH Authentication protocol runs over the SSH Transport protocol as a transport protocol service.

• connection

  protected ConnectionProtocol connection

  The SSH Connection protocol implementation for this SSH client. The connection protocol runs over the SSH Transport protocol as a transport protocol service and is started by the authentication protocol after a successful authentication.

• forwarding

  protected ForwardingClient forwarding

  Provides a high level management interface for SSH port forwarding.

• transport

  protected TransportProtocolClient transport

  The SSH Transport protocol implementation for this SSH Client.

• authenticationState

  protected int authenticationState

  The current state of the authentication for the current connection.

• socketTimeout

  protected int socketTimeout

  The timeout in milliseconds for the underlying transport provider (typically a Socket).

• eventHandler

  protected SshEventAdapter eventHandler

  A Transport protocol event handler instance that receives notifications of transport layer events such as Socket timeouts and disconnection.

• activeChannels

  protected java.util.Vector activeChannels

  The currently active channels for this SSH Client connection.

• activeChannelListener

  protected com.sshtools.j2ssh.SshClient.ActiveChannelEventListener activeChannelListener

  An channel event listener implemention to maintain the active channel list.

• useDefaultForwarding

  protected boolean useDefaultForwarding

  Flag indicating whether the forwarding instance is created when the connection is made.

Constructor Detail

• SshClient

  public SshClient()

  Contructs an unitilialized SshClient ready for connecting.

Method Detail

• getAuthenticationBanner

  public java.lang.String getAuthenticationBanner​(int timeout)
                                           throws java.io.IOException

  Returns the server's authentication banner.

  In some jurisdictions, sending a warning message before authentication may be relevant for getting legal protection. Many UNIX machines, for example, normally display text from `/etc/issue', or use "tcp wrappers" or similar software to display a banner before issuing a login prompt.

  The server may or may not send this message. Call this method to retrieve the message, specifying a timeout limit to wait for the message.

  Parameters:

  timeout - The number of milliseconds to wait for the banner message before returning

  Returns:

  The server's banner message

  Throws:

  java.io.IOException - If an IO error occurs reading the message

  Since:

  0.2.0

• getAvailableAuthMethods

  public java.util.List getAvailableAuthMethods​(java.lang.String username)
                                         throws java.io.IOException

  Returns the list of available authentication methods for a given user.

  A client may request a list of authentication methods that may continue by using the "none" authentication method.This method calls the "none" method and returns the available authentication methods.

  Parameters:

  username - The name of the account for which you require the available authentication methods

  Returns:

  A list of Strings, for example "password", "publickey" & "keyboard-interactive"

  Throws:

  java.io.IOException - If an IO error occurs during the operation

  Since:

  0.2.0

• isConnected

  public boolean isConnected()

  Returns the connection state of the client.

  Returns:

  true if the client is connected, false otherwise

  Since:

  0.2.0

• isAuthenticated

  public boolean isAuthenticated()

  Evaluate whether the client has successfully authenticated.

  Returns:

  true if the client is authenticated, otherwise false

• getServerId

  public java.lang.String getServerId()

  Returns the identification string sent by the server during protocol negotiation. For example "SSH-2.0-OpenSSH_p3.4".

  Returns:

  The server's identification string.

  Since:

  0.2.0

• getServerHostKey

  public SshPublicKey getServerHostKey()

  Returns the server's public key supplied during key exchange.

  Returns:

  the server's public key

  Since:

  0.2.0

• getConnectionState

  public TransportProtocolState getConnectionState()

  Returns the transport protocol's connection state.

  Returns:

  The transport protocol's state

  Since:

  0.2.0

• getForwardingClient

  public ForwardingClient getForwardingClient()

  Returns the default port forwarding manager.

  Returns:

  This connection's forwarding client

  Since:

  0.2.0

• getRemoteEOL

  public int getRemoteEOL()

  Return's a rough guess at the server's EOL setting. This is simply derived from the identification string and should not be used as a cast iron proof on the EOL setting.

  Returns:

  The transport protocol's EOL constant

  Since:

  0.2.0

• addEventHandler

  public void addEventHandler​(SshEventAdapter eventHandler)

  Set the event handler for the underlying transport protocol.

   ssh.setEventHandler(new TransportProtocolEventHandler() {
  
     public void onSocketTimeout(TransportProtocol transport) {
  
       // Do something to handle the socket timeout
  
     }
  
     public void onDisconnect(TransportProtocol transport) {
       // Perhaps some clean up?
     }
   });
   

  Parameters:

  eventHandler - The event handler instance to receive transport protocol events

  Since:

  0.2.0

  See Also:

  TransportProtocolEventHandler

• setSocketTimeout

  public void setSocketTimeout​(int milliseconds)

  Set's the socket timeout (in milliseconds) for the underlying transport provider. This MUST be called prior to connect.

  SshClient ssh = new SshClient(); ssh.setSocketTimeout(30000); ssh.connect("hostname");

  Parameters:

  milliseconds - The number of milliseconds without activity before the timeout event occurs

  Since:

  0.2.0

• getRemoteEOLString

  public java.lang.String getRemoteEOLString()

  Return's a rough guess at the server's EOL setting. This is simply derived from the identification string and should not be used as a cast iron proof on the EOL setting.

  Returns:

  The EOL string

  Since:

  0.2.0

• getConnectionProperties

  public SshConnectionProperties getConnectionProperties()

  Get the connection properties for this connection.

  Returns:

• authenticate

  public int authenticate​(SshAuthenticationClient auth)
                   throws java.io.IOException

  Authenticate the user on the remote host.

  To authenticate the user, create an SshAuthenticationClient instance and configure it with the authentication details.

  PasswordAuthenticationClient pwd = new PasswordAuthenticationClient(); pwd.setUsername("root"); pwd.setPassword("xxxxxxxxx"); int result = ssh.authenticate(pwd);

  The method returns a result value will one of the public static values defined in AuthenticationProtocolState. These are
  
  COMPLETED - The authentication succeeded.
  PARTIAL - The authentication succeeded but a further authentication method is required.
  FAILED - The authentication failed.
  CANCELLED - The user cancelled authentication (can only be returned when the user is prompted for information.
  

  Parameters:

  auth - A configured SshAuthenticationClient instance ready for authentication

  Returns:

  The authentication result

  Throws:

  java.io.IOException - If an IO error occurs during authentication

  Since:

  0.2.0

• acceptsKey

  public boolean acceptsKey​(java.lang.String username,
                            SshPublicKey key)
                     throws java.io.IOException

  Determine whether a private/public key pair will be accepted for public key authentication.

  When using public key authentication, the signing of data could take some time depending upon the available machine resources. By calling this method, you can determine whether the server will accept a key for authentication by providing the public key. The server will verify the key against the user's authorized keys and return true should the public key be authorized. The caller can then proceed with the private key operation.

  Parameters:

  username - The username for authentication

  key - The public key for which authentication will be attempted

  Returns:

  true if the server will accept the key, otherwise false

  Throws:

  java.io.IOException - If an IO error occurs during the operation

  SshException

  Since:

  0.2.0

• connect

  public void connect​(java.lang.String hostname)
               throws java.io.IOException

  Connect the client to the server using default connection properties.

  This call attempts to connect to the hostname specified on the standard SSH port of 22 and uses all the default connection properties. This call is the equivilent of calling:

   SshConnectionProperties properties = new
                             SshConnectionProperties();
   properties.setHostname("hostname");
   ssh.connect(properties);
   

  Parameters:

  hostname - The hostname of the server to connect

  Throws:

  java.io.IOException - If an IO error occurs during the connect operation

  Since:

  0.2.0

  See Also:

  connect(com.sshtools.j2ssh.configuration.SshConnectionProperties)

• connect

  public void connect​(java.lang.String hostname,
                      HostKeyVerification hosts)
               throws java.io.IOException

  Connect the client to the server using the default connection properties.

  This call attempts to connect to the hostname specified on the standard SSH port of 22 and uses all the default connection properties. When this method returns the connection has been established, the server's identity been verified and the connection is ready for user authentication. Host key verification will be performed using the host key verification instance provided:

   // Connect and consult $HOME/.ssh/known_hosts
   ssh.connect("hostname", new ConsoleKnownHostsKeyVerification());
   // Connect and allow any host
   ssh.connect("hostname", new
                   IgnoreHostKeyVerification());
   

  You can provide your own host key verification process by implementing the HostKeyVerification interface.

  Parameters:

  hostname - The hostname of the server to connect

  hosts - The host key verification instance to consult for host key validation

  Throws:

  java.io.IOException - If an IO error occurs during the connect operation

  Since:

  0.2.0

  See Also:

  connect(com.sshtools.j2ssh.configuration.SshConnectionProperties, com.sshtools.j2ssh.transport.HostKeyVerification)

• connect

  public void connect​(java.lang.String hostname,
                      int port)
               throws java.io.IOException

  Connect the client to the server on a specified port with default connection properties.

  This call attempts to connect to the hostname and port specified. This call is the equivilent of calling:

  SshConnectionProperties properties = new SshConnectionProperties(); properties.setHostname("hostname"); properties.setPort(10022); ssh.connect(properties);

  Parameters:

  hostname - The hostname of the server to connect

  port - The port to connect

  Throws:

  java.io.IOException - If an IO error occurs during the connect operation

  Since:

  0.2.0

  See Also:

  connect(com.sshtools.j2ssh.configuration.SshConnectionProperties)

• connect

  public void connect​(java.lang.String hostname,
                      int port,
                      HostKeyVerification hosts)
               throws java.io.IOException

  Connect the client to the server on a specified port with default connection properties.

  This call attempts to connect to the hostname and port specified. When this method returns the connection has been established, the server's identity been verified and the connection is ready for user authentication. Host key verification will be performed using the host key verification instance provided:

   // Connect and consult $HOME/.ssh/known_hosts
   ssh.connect("hostname", new ConsoleKnownHostsKeyVerification());
   // Connect and allow any host
   ssh.connect("hostname", new
                   IgnoreHostKeyVerification());
   

  You can provide your own host key verification process by implementing the HostKeyVerification interface.

  Parameters:

  hostname - The hostname of the server to connect

  port - The port to connect

  hosts - The host key verification instance to consult for host key validation

  Throws:

  java.io.IOException - If an IO error occurs during the connect operation

  Since:

  0.2.0

  See Also:

  connect(com.sshtools.j2ssh.configuration.SshConnectionProperties, com.sshtools.j2ssh.transport.HostKeyVerification)

• connect

  public void connect​(SshConnectionProperties properties)
               throws java.io.IOException

  Connect the client to the server with the specified properties.

  This call attempts to connect to using the connection properties specified. When this method returns the connection has been established, the server's identity been verified and the connection is ready for user authentication. To use this method first create a properties instance and set the required fields.

   SshConnectionProperties properties = new
                           SshConnectionProperties();
   properties.setHostname("hostname");
   properties.setPort(10022);
   properties.setPrefCSEncryption("blowfish-cbc");
   ssh.connect(properties);
   

  Host key verification will be performed using ConsoleKnownHostsKeyVerification and so this call is the equivilent of calling:

   ssh.connect("hostname", new ConsoleKnownHostsKeyVerification());
   

  If the key is not matched to any keys already in the $HOME/.ssh/known_hosts file, the user will be prompted via the console to confirm the identity of the remote server. The user will receive the following prompt.

  The host shell.sourceforge.net is currently unknown to the system The host key fingerprint is: 1024: 4c 68 3 d4 5c 58 a6 1d 9d 17 13 24 14 48 ba 99 Do you want to allow this host key? [Yes|No|Always]:

  Selecting the "always" option will write the key to the known_hosts file.

  Parameters:

  properties - The connection properties

  Throws:

  java.io.IOException - If an IO error occurs during the connect operation

  Since:

  0.2.0

• connect

  public void connect​(SshConnectionProperties properties,
                      HostKeyVerification hostVerification)
               throws java.net.UnknownHostException,
                      java.io.IOException

  Connect the client to the server with the specified properties.

  This call attempts to connect to using the connection properties specified. When this method returns the connection has been established, the server's identity been verified and the connection is ready for user authentication. To use this method first create a properties instance and set the required fields.

   SshConnectionProperties properties = new
                               SshConnectionProperties();
   properties.setHostname("hostname");
   properties.setPort(22);             // Defaults to 22
   // Set the prefered client->server encryption
   ssh.setPrefCSEncryption("blowfish-cbc");
   // Set the prefered server->client encrpytion
   ssh.setPrefSCEncrpyion("3des-cbc");
   ssh.connect(properties);
   

  Host key verification will be performed using the host key verification instance provided:
  

   // Connect and consult $HOME/.ssh/known_hosts
   ssh.connect("hostname", new ConsoleKnownHostsKeyVerification());
   // Connect and allow any host
   ssh.connect("hostname", new
                   IgnoreHostKeyVerification());
   

  You can provide your own host key verification process by implementing the HostKeyVerification interface.

  Parameters:

  properties - The connection properties

  hostVerification - The host key verification instance to consult for host key validation

  Throws:

  java.net.UnknownHostException - If the host is unknown

  java.io.IOException - If an IO error occurs during the connect operation

  Since:

  0.2.0

• setKexTimeout

  public void setKexTimeout​(long seconds)
                     throws java.io.IOException

  Sets the timeout value for the key exchange.

  When this time limit is reached the transport protocol will initiate a key re-exchange. The default value is one hour with the minumin timeout being 60 seconds.

  Parameters:

  seconds - The number of seconds beofre key re-exchange

  Throws:

  java.io.IOException - If the timeout value is invalid

  Since:

  0.2.0

• setKexTransferLimit

  public void setKexTransferLimit​(long kilobytes)
                           throws java.io.IOException

  Sets the key exchance transfer limit in kilobytes.

  Once this amount of data has been transfered the transport protocol will initiate a key re-exchange. The default value is one gigabyte of data with the mimimun value of 10 kilobytes.

  Parameters:

  kilobytes - The data transfer limit in kilobytes

  Throws:

  java.io.IOException - If the data transfer limit is invalid

• setSendIgnore

  public void setSendIgnore​(boolean sendIgnore)

  Set's the send ignore flag to send random data packets.

  If this flag is set to true, then the transport protocol will send additional SSH_MSG_IGNORE packets with random data.

  Parameters:

  sendIgnore - true if you want to turn on random packet data, otherwise false

  Since:

  0.2.0

• setUseDefaultForwarding

  public void setUseDefaultForwarding​(boolean useDefaultForwarding)

  Turn the default forwarding manager on/off.

  If this flag is set to false before connection, the client will not create a port forwarding manager. Use this to provide you own forwarding implementation.

  Parameters:

  useDefaultForwarding - Set to false if you not wish to use the default forwarding manager.

  Since:

  0.2.0

• disconnect

  public void disconnect()

  Disconnect the client.

  Since:

  0.2.0

• getOutgoingByteCount

  public long getOutgoingByteCount()

  Returns the number of bytes transmitted to the remote server.

  Returns:

  The number of bytes transmitted

  Since:

  0.2.0

• getIncomingByteCount

  public long getIncomingByteCount()

  Returns the number of bytes received from the remote server.

  Returns:

  The number of bytes received

  Since:

  0.2.0

• getActiveChannelCount

  public int getActiveChannelCount()

  Returns the number of active channels for this client.

  This is the total count of sessions, port forwarding, sftp, scp and custom channels currently open.

  Returns:

  The number of active channels

  Since:

  0.2.0

• getActiveChannels

  public java.util.List getActiveChannels()

  Returns the list of active channels.

  Returns:

  The list of active channels

  Since:

  0.2.0

• hasActiveSession

  public boolean hasActiveSession​(java.lang.String type)

  Returns true if there is an active session channel of the specified type.

  When a session is created, it is assigned a default type. For instance, when a session is created it as a type of "uninitialized"; however when a shell is started on the session, the type is set to "shell". This also occurs for commands where the type is set to the command which is executed and subsystems where the type is set to the subsystem name. This allows each session to be saved in the active session channel's list and recalled later. It is also possible to set the session channel's type using the setSessionType method of the SessionChannelClient class.

   if(ssh.hasActiveSession("shell")) {
        SessionChannelClient session =
             ssh.getActiveSession("shell");
   }
   

  Parameters:

  type - The string specifying the channel type

  Returns:

  true if an active session channel exists, otherwise false

  Since:

  0.2.0

• getActiveSession

  public SessionChannelClient getActiveSession​(java.lang.String type)
                                        throws java.io.IOException

  Returns the active session channel of the given type.

  Parameters:

  type - The type fo session channel

  Returns:

  The session channel instance

  Throws:

  java.io.IOException - If the session type does not exist

  Since:

  0.2.0

• isActiveChannel

  public boolean isActiveChannel​(Channel channel)

  Determine whether the channel supplied is an active channel

  Parameters:

  channel -

  Returns:

• openSessionChannel

  public SessionChannelClient openSessionChannel()
                                          throws java.io.IOException

  Open's a session channel on the remote server.

  A session channel may be used to start the user's shell, execute a command or start a subsystem such as SFTP.

  Returns:

  An new session channel

  Throws:

  java.io.IOException - If authentication has not been completed, the server refuses to open the channel or a general IO error occurs

  Since:

  0.2.0

  See Also:

  SessionChannelClient

• openSessionChannel

  public SessionChannelClient openSessionChannel​(ChannelEventListener eventListener)
                                          throws java.io.IOException

  Open's a session channel on the remote server.

  A session channel may be used to start the user's shell, execute a command or start a subsystem such as SFTP.

  Parameters:

  eventListener - an event listner interface to add to the channel

  Returns:

  Throws:

  java.io.IOException

  SshException

• openSftpClient

  public SftpClient openSftpClient()
                            throws java.io.IOException

  Open an SFTP client for file transfer operations.

   SftpClient sftp = ssh.openSftpClient();
   sftp.cd("foo");
   sftp.put("somefile.txt");
   sftp.quit();
   

  Returns:

  Returns an initialized SFTP client

  Throws:

  java.io.IOException - If an IO error occurs during the operation

  Since:

  0.2.0

  See Also:

  SftpClient

• openSftpClient

  public SftpClient openSftpClient​(ChannelEventListener eventListener)
                            throws java.io.IOException

  Open an SFTP client for file transfer operations. Adds the supplied event listener to the underlying channel.

  Parameters:

  eventListener -

  Returns:

  Throws:

  java.io.IOException

• hasActiveSftpClient

  public boolean hasActiveSftpClient()

  Determine if there are existing sftp clients open

  Returns:

• getActiveSftpClient

  public SftpClient getActiveSftpClient()
                                 throws java.io.IOException

  Get an active sftp client

  Returns:

  Throws:

  java.io.IOException

  SshException

• openScpClient

  public ScpClient openScpClient()
                          throws java.io.IOException

  Open an SCP client for file transfer operations where SFTP is not supported.

  Sets the local working directory to the user's home directory

   ScpClient scp = ssh.openScpClient();
   scp.put("somefile.txt");
   

  Returns:

  An initialized SCP client

  Throws:

  java.io.IOException - If an IO error occurs during the operation

  Since:

  0.2.0

  See Also:

  ScpClient

• openScpClient

  public ScpClient openScpClient​(java.io.File cwd)
                          throws java.io.IOException

  Open an SCP client for file transfer operations where SFTP is not supported.

  This method sets a local current working directory.

   ScpClient scp = ssh.openScpClient("foo");
   scp.put("somefile.txt");
   

  Parameters:

  cwd - The local directory as the base for all local files

  Returns:

  An intialized SCP client

  Throws:

  java.io.IOException - If an IO error occurs during the operation

  Since:

  0.2.0

  See Also:

  SftpClient

• openSftpChannel

  public SftpSubsystemClient openSftpChannel()
                                      throws java.io.IOException

  Open's an Sftp channel.

  Use this sftp channel if you require a lower level api into the SFTP protocol.

  Returns:

  an initialized sftp subsystem instance

  Throws:

  java.io.IOException - if an IO error occurs or the channel cannot be opened

  Since:

  0.2.0

• openSftpChannel

  public SftpSubsystemClient openSftpChannel​(ChannelEventListener eventListener)
                                      throws java.io.IOException

  Open an SftpSubsystemChannel. For advanced use only

  Parameters:

  eventListener -

  Returns:

  Throws:

  java.io.IOException

  SshException

• openChannel

  public boolean openChannel​(Channel channel)
                      throws java.io.IOException

  Open's a channel.

  Call this method to open a custom channel. This method is used by all other channel opening methods. For example the openSessionChannel method could be implemented as:
  

   SessionChannelClient session =
                   new SessionChannelClient();
   if(ssh.openChannel(session)) {
      // Channel is now open
   }
   

  Parameters:

  channel -

  Returns:

  true if the channel was opened, otherwise false

  Throws:

  java.io.IOException - if an IO error occurs

  SshException

  Since:

  0.2.0

• allowChannelOpen

  public void allowChannelOpen​(java.lang.String channelName,
                               ChannelFactory cf)
                        throws java.io.IOException

  Instructs the underlying connection protocol to allow channels of the given type to be opened by the server.

  The client does not allow channels to be opened by default. Call this method to allow the server to open channels by providing a ChannelFactory implementation to create instances upon request.

  Parameters:

  channelName - The channel type name

  cf - The factory implementation that will create instances of the channel when a channel open request is recieved.

  Throws:

  java.io.IOException - if an IO error occurs

  Since:

  0.2.0

• denyChannelOpen

  public void denyChannelOpen​(java.lang.String channelName)
                       throws java.io.IOException

  Stops the specified channel type from being opended.

  Parameters:

  channelName - The channel type name

  Throws:

  java.io.IOException - if an IO error occurs

  Since:

  0.2.1

• sendGlobalRequest

  public byte[] sendGlobalRequest​(java.lang.String requestName,
                                  boolean wantReply,
                                  byte[] requestData)
                           throws java.io.IOException

  Send a global request to the server.

  The SSH specification provides a global request mechanism which is used for starting/stopping remote forwarding. This is a general mechanism which can be used for other purposes if the server supports the global requests.

  Parameters:

  requestName - The name of the global request

  wantReply - true if the server should send an explict reply

  requestData - the global request data

  Returns:

  true if the global request succeeded or wantReply==false, otherwise false

  Throws:

  java.io.IOException - if an IO error occurs

  Since:

  0.2.0