SSHTunnel Class

Properties Methods Events Config Settings Errors

The SSHTunnel class can be used to tunnel data through an SSH server to a remote location.

Syntax

ipworksssh.Sshtunnel

Remarks

The SSHTunnel class implements a daemon that accepts connections and tunnels the data from those connections over a Secure Shell (SSH) connection to a remote location.

First, set SSHHost to the server you wish to use to tunnel the data. SSHUser, SSHPassword and SSHCert can be used to authenticate the tunneling connection.

Second, set SSHForwardHost to the hostname or IP address of the destination machine, and SSHForwardPort to the port to which you wish to send data. Finally, call StartListening. The class will listen for connections on the interface identified by LocalHost and LocalPort.

When a client attempts to connect to the class, the class will fire a ConnectionRequest event that can be used to accept or reject the connection. If the connection is accepted, the class will attempt to logon to the SSHHost, and will tell the server to connect remotely to another machine. Once this process is complete, the tunnel will be established and data can be securely transmitted from end to end.

Example: Connecting Between Networks

A client which exists in Network A wishes to connect to a resource that exists in Network B. Both networks are secured by a firewall, making it difficult to freely connect to resources within the other network. However, Network B contains an SSH server which supports tunneling. An SSHTunnel class set up with Network A can be used to access any resource in Network B.

The SSHHost and SSHPort properties must be set to the hostname and port exposed by Network B's firewall. SSHForwardHost and SSHForwardPort are then set to the value of the resource within Network B to which the client in Network A wishes to connect. Any client in Network A can then connect to the SSHTunnel instance's LocalHost and LocalPort.

As clients within Network A connect to the SSHTunnel, the class will forward the connections, secured by SSH, through the network firewalls to the SSH server in Network B. The SSH server will then connect to the resource within Network B and forward all data received from the SSHTunnel instance to that resource. All data received from the resource will then be forwarded back to the original client in Network A.

Dynamic Forwarding

Dynamic forwarding is a feature provided by SSH that leverages the SOCKS protocol. With dynamic forwarding, the SSHTunnel component acts as a SOCKS proxy, and all relevant traffic is relayed through the SSH connection to the destination defined by the client that made the request. The SSHTunnel component supports dynamic forwarding automatically when SSHForwardHost and SSHForwardPort are not specified (the forwarding host is determined dynamically).

The client making requests through SSHTunnel must be configured to use a SOCKS proxy, where the proxy port is the same as the LocalPort property. In IPWorks components a SOCKS proxy can be enabled like so:

// Enable the SOCKS proxy for IPWorks' HTTP component http.Firewall.FirewallType = nsoftware.IPWorks.FirewallTypes.fwSOCKS5; http.Firewall.Port = 1234; //The port set in the SSHTunnel LocalPort property http.Firewall.Host = "localhost"; //The hostname or IP address where SSHTunnel is listening

Note: SSHTunnel can support either dynamic forwarding (SSHForwardHost and SSHForwardPort are not set), or standard forwarding (SSHForwardHost and SSHForwardPort are set). It cannot support both modes at the same time. As a result it is expected that clients connecting to the SSHTunnel component are configured in a way that matches the configuration of the SSHTunnel component (dynamic or standard forwarding). For example, if SSHTunnel has the SSHForwardHost and SSHForwardPort properties set, then the client must NOT treat SSHTunnel as a SOCKS proxy. If the SSHTunnel does not have the aforementioned properties set, then the client MUST treat SSHTunnel as a SOCKS proxy.

Note: Server components are designed to process events as they occur. To ensure that events are processed in a timely manner, DoEvents should be called in a loop after the server is started.

Property List

The following is the full list of the properties of the class with short descriptions. Click on the links for further details.


Connected	This shows whether the class is connected.
ConnectionBacklog	This property includes the maximum number of pending connections maintained by the Transmission Control Protocol (TCP)/IP subsystem.
Connections	This property includes a collection of currently connected clients.
DefaultEOL	This property includes a default end-of-line (EOL) value to be used by incoming connections.
DefaultSingleLineMode	This property tells the class whether or not to treat new connections as line oriented.
DefaultTimeout	This property includes an initial timeout value to be used by incoming connections.
Firewall	A set of properties related to firewall access.
KeepAlive	When True, KEEPALIVE packets are enabled (for long connections).
Linger	When set to True, connections are terminated gracefully.
Listening	If set to True, the class accepts incoming connections on LocalPort.
LocalHost	The name of the local host or user-assigned IP interface through which connections are initiated or accepted.
LocalPort	The TCP port in the local host where the class binds.
SSHAcceptServerHostKey	Instructs the class to accept the server host key that matches the supplied key.
SSHAuthMode	The authentication method to be used the class when calling SSHLogon .
SSHCert	A certificate to be used for authenticating the SSHUser .
SSHCompressionAlgorithms	A comma-separated list containing all allowable compression algorithms.
SSHEncryptionAlgorithms	A comma-separated list containing all allowable encryption algorithms.
SSHForwardHost	The address of the remote host. Domain names are resolved to IP addresses.
SSHForwardPort	The TCP port in the remote host.
SSHHost	The address of the SSH host.
SSHPassword	The password for SSH password-based authentication.
SSHPort	The port on the SSH server where the SSH service is running; by default, 22.
SSHUser	The username for SSH authentication.

Method List

The following is the full list of the methods of the class with short descriptions. Click on the links for further details.


Config	Sets or retrieves a configuration setting.
Connect	Connects to the SSH host without logging in.
DecodePacket	Decodes a hex-encoded SSH packet.
Disconnect	This method disconnects the specified client.
DoEvents	Processes events from the internal message queue.
EncodePacket	Hex encodes an SSH packet.
GetSSHParam	Used to read a field from an SSH packet's payload.
GetSSHParamBytes	Used to read a field from an SSH packet's payload.
Reset	Reset the class.
SetSSHParam	Used to write a field to the end of a payload.
Shutdown	This method shuts down the server.
StartListening	This method starts listening for incoming connections.
StopListening	This method stops listening for new connections.

Event List

The following is the full list of the events fired by the class with short descriptions. Click on the links for further details.


Connected	This event is fired immediately after a connection completes (or fails).
ConnectionRequest	This event is fired when a request for connection comes from a remote host.
DataIn	This event is fired when data come in.
Disconnected	Fired when a connection is closed.
Error	Information about errors during data delivery.
Log	Fires once for each log message.
ReconnectAttempt	Fires when attempting to reconnect.
SSHCustomAuth	Fired when the class is doing custom authentication.
SSHKeyboardInteractive	Fired when the class receives a request for user input from the server.
SSHServerAuthentication	Fired after the server presents its public key to the client.
SSHStatus	Shows the progress of the secure connection.

Config Settings

The following is a list of config settings for the class with short descriptions. Click on the links for further details.


AutoReconnect	Whether to automatically reconnect.
MaxRetryCount	The maximum number of retries when reconnecting.
RetryInterval	The interval in seconds between reconnect attempts.
ShutdownChannelOnEOF	Whether the client will shutdown the channel after receiving an EOF packet from the remote host.
ChannelDataEOL[ChannelId]	Used to break the incoming data stream into chunks.
ChannelDataEOLFound[ChannelId]	Determines if ChannelDataEOL was found.
ClientSSHVersionString	The SSH version string used by the class.
EnablePageantAuth	Whether to use a key stored in Pageant to perform client authentication.
KerberosDelegation	If true, asks for credentials with delegation enabled during authentication.
KerberosRealm	The fully qualified domain name of the Kerberos Realm to use for GSSAPI authentication.
KerberosSPN	The Kerberos Service Principal Name of the SSH host.
KeyRenegotiationThreshold	Sets the threshold for the SSH Key Renegotiation.
LogLevel	Specifies the level of detail that is logged.
MaxChannelDataLength[ChannelId]	The maximum amount of data to accumulate when no ChannelDataEOL is found.
MaxPacketSize	The maximum packet size of the channel, in bytes.
MaxWindowSize	The maximum window size allowed for the channel, in bytes.
NegotiatedStrictKex	Returns whether strict key exchange was negotiated to be used.
PasswordPrompt	The text of the password prompt used in keyboard-interactive authentication.
PreferredDHGroupBits	The size (in bits) of the preferred modulus (p) to request from the server.
RecordLength	The length of received data records.
ServerSSHVersionString	The remote host's SSH version string.
SignedSSHCert	The CA signed client public key used when authenticating.
SSHAcceptAnyServerHostKey	If set the class will accept any key presented by the server.
SSHAcceptServerCAKey	The CA public key that signed the server's host key.
SSHAcceptServerHostKeyFingerPrint	The fingerprint of the server key to accept.
SSHFingerprintHashAlgorithm	The algorithm used to calculate the fingerprint.
SSHFingerprintMD5	The server hostkey's MD5 fingerprint.
SSHFingerprintSHA1	The server hostkey's SHA1 fingerprint.
SSHFingerprintSHA256	The server hostkey's SHA256 fingerprint.
SSHKeepAliveCountMax	The maximum number of keep alive packets to send without a response.
SSHKeepAliveInterval	The interval between keep alive packets.
SSHKeyExchangeAlgorithms	Specifies the supported key exchange algorithms.
SSHKeyRenegotiate	Causes the class to renegotiate the SSH keys.
SSHMacAlgorithms	Specifies the supported Mac algorithms.
SSHPubKeyAuthSigAlgorithms	Specifies the enabled signature algorithms that may be used when attempting public key authentication.
SSHPublicKeyAlgorithms	Specifies the supported public key algorithms for the server's public key.
SSHVersionPattern	The pattern used to match the remote host's version string.
TryAllAvailableAuthMethods	If set to true, the class will try all available authentication methods.
UseStrictKeyExchange	Specifies how strict key exchange is supported.
WaitForChannelClose	Whether to wait for channels to be closed before disconnected.
WaitForServerDisconnect	Whether to wait for the server to close the connection.
CloseStreamAfterTransfer	If true, the class will close the upload or download stream after the transfer.
ConnectionTimeout	Sets a separate timeout value for establishing a connection.
FirewallAutoDetect	Tells the class whether or not to automatically detect and use firewall system settings, if available.
FirewallHost	Name or IP address of firewall (optional).
FirewallListener	If true, the class binds to a SOCKS firewall as a server (TCPClient only).
FirewallPassword	Password to be used if authentication is to be used when connecting through the firewall.
FirewallPort	The TCP port for the FirewallHost;.
FirewallType	Determines the type of firewall to connect through.
FirewallUser	A user name if authentication is to be used connecting through a firewall.
KeepAliveInterval	The retry interval, in milliseconds, to be used when a TCP keep-alive packet is sent and no response is received.
KeepAliveTime	The inactivity time in milliseconds before a TCP keep-alive packet is sent.
Linger	When set to True, connections are terminated gracefully.
LingerTime	Time in seconds to have the connection linger.
LocalHost	The name of the local host through which connections are initiated or accepted.
LocalPort	The port in the local host where the class binds.
MaxLineLength	The maximum amount of data to accumulate when no EOL is found.
MaxTransferRate	The transfer rate limit in bytes per second.
ProxyExceptionsList	A semicolon separated list of hosts and IPs to bypass when using a proxy.
TCPKeepAlive	Determines whether or not the keep alive socket option is enabled.
TcpNoDelay	Whether or not to delay when sending packets.
UseIPv6	Whether to use IPv6.
UseNTLMv2	Whether to use NTLM V2.
AbsoluteTimeout	Determines whether timeouts are inactivity timeouts or absolute timeouts.
FirewallData	Used to send extra data to the firewall.
InBufferSize	The size in bytes of the incoming queue of the socket.
OutBufferSize	The size in bytes of the outgoing queue of the socket.
AllowedClients	A comma-separated list of host names or IP addresses that can access the class.
BindExclusively	Whether or not the class considers a local port reserved for exclusive use.
BlockedClients	A comma-separated list of host names or IP addresses that cannot access the class.
CloseStreamAfterTransfer	If true, the class will close the upload or download stream after the transfer.
DefaultConnectionTimeout	The inactivity timeout applied to the SSL handshake.
InBufferSize	The size in bytes of the incoming queue of the socket.
KeepAliveInterval	The retry interval, in milliseconds, to be used when a TCP keep-alive packet is sent and no response is received.
KeepAliveTime	The inactivity time in milliseconds before a TCP keep-alive packet is sent.
MaxConnections	The maximum number of connections available.
OutBufferSize	The size in bytes of the outgoing queue of the socket.
PreferredDHGroupBits	Size of the Diffie-Hellman group, in bits.
TcpNoDelay	Whether or not to delay when sending packets.
UseIPv6	Whether to use IPv6.
BuildInfo	Information about the product's build.
GUIAvailable	Whether or not a message loop is available for processing events.
LicenseInfo	Information about the current license.
MaskSensitive	Whether sensitive data is masked in log messages.
UseDaemonThreads	Whether threads created by the class are daemon threads.
UseFIPSCompliantAPI	Tells the class whether or not to use FIPS certified APIs.
UseInternalSecurityAPI	Whether or not to use the system security libraries or an internal implementation.

Connected Property (SSHTunnel Class)

This shows whether the class is connected.

Syntax


public boolean isConnected();


public void setConnected(boolean connected);

Default Value

False

Remarks

This property is used to determine whether or not the class is connected to the remote host.

Note: It is recommended to use the Connect or Disconnect method instead of setting this property.

This property is not available at design time.

ConnectionBacklog Property (SSHTunnel Class)

This property includes the maximum number of pending connections maintained by the Transmission Control Protocol (TCP)/IP subsystem.

Syntax


public int getConnectionBacklog();


public void setConnectionBacklog(int connectionBacklog);

Default Value

Remarks

This property contains the maximum number of pending connections maintained by the TCP/IP subsystem. This value reflects the SOMAXCONN option for the main listening socket. The default value for most systems is 5. You may set this property to a larger value if the server is expected to receive a large number of connections, and queuing them is desirable.

This property is not available at design time.

Connections Property (SSHTunnel Class)

This property includes a collection of currently connected clients.

Syntax


public ConnectionMap getConnections();

Remarks

This property contains a collection of currently connected clients. All of the connections may be managed using this property. Each connection is described by the different fields of the Connection type.

This collection is a hash-table type of collection, in which the Connection Id string is used as the key to the desired connection. You may acquire the key for a given connection through the Connected event.

Example (Broadcasting Data) Iterator keys = tcpserver1.getConnections().keySet().iterator(); while (keys.hasNext()) { Connection c = (Connection) tcpserver1.getConnections().get(keys.next()); c.setDataToSend("Broadcast Data"); }

This property is read-only.

Please refer to the Connection type for a complete list of fields.

DefaultEOL Property (SSHTunnel Class)

This property includes a default end-of-line (EOL) value to be used by incoming connections.

Syntax


public byte[] getDefaultEOL();


public void setDefaultEOL(byte[] defaultEOL);

Default Value

Remarks

This property contains a default end-of-line (EOL) value to be used by incoming connections. Once the class accepts and establishes an inbound connection, it will set that connection's EOL to the value in this property. By default, this value is empty (""), meaning that data will be fired as it is received.

DefaultSingleLineMode Property (SSHTunnel Class)

This property tells the class whether or not to treat new connections as line oriented.

Syntax


public boolean isDefaultSingleLineMode();


public void setDefaultSingleLineMode(boolean defaultSingleLineMode);

Default Value

False

Remarks

This property instructs the component whether or not to treat newly established connections as line-oriented protocols. If this value is True, newly accepted connections will read the incoming data stream as lines separated by a carriage return line feed (CRLF), carriage return (CR), or line feed (LF) and will ignore the end of lines (EOLs).

DefaultTimeout Property (SSHTunnel Class)

This property includes an initial timeout value to be used by incoming connections.

Syntax


public int getDefaultTimeout();


public void setDefaultTimeout(int defaultTimeout);

Default Value

Remarks

This property is used by the class to set the operational timeout value of all inbound connections once they are established.

This property defines the timeout when sending data. When SSLEnabled is False, a value of 0 means data will be sent asynchronously, and a positive value means data is sent synchronously.

When SSLEnabled is True, all data are sent synchronously regardless of the Timeout value.

Firewall Property (SSHTunnel Class)

A set of properties related to firewall access.

Syntax


public Firewall getFirewall();


public void setFirewall(Firewall firewall);

Remarks

This is a Firewall-type property, which contains fields describing the firewall through which the class will attempt to connect.

Please refer to the Firewall type for a complete list of fields.

KeepAlive Property (SSHTunnel Class)

When True, KEEPALIVE packets are enabled (for long connections).

Syntax


public boolean isKeepAlive();


public void setKeepAlive(boolean keepAlive);

Default Value

False

Remarks

This property enables the SO_KEEPALIVE option on the incoming connections. This option prevents long connections from timing out in case of inactivity.

Note: System Transmission Control Protocol (TCP)/IP stack implementations are not required to support SO_KEEPALIVE.

This property is shared among incoming connections. When the property is set, the corresponding value is set for incoming connections as they are accepted. Existing connections are not modified.

Linger Property (SSHTunnel Class)

When set to True, connections are terminated gracefully.

Syntax


public boolean isLinger();


public void setLinger(boolean linger);

Default Value

True

Remarks

This property controls how a connection is closed. The default is True. In this case, the connection is closed only after all the data are sent. Setting it to False forces an abrupt (hard) disconnection. Any data that were in the sending queue may be lost.

The default behavior (which is also the default mode for stream sockets) might result in an indefinite delay in closing the connection. Although the class returns control immediately, the system might indefinitely hold system resources until all pending data are sent (even after your application closes). This means that valuable system resources might be wasted.

Setting this property to False forces an immediate disconnection. If you know that the other side has received all the data you have sent (e.g., by a client acknowledgment), then setting this property to False might be the appropriate course of action.

This property is shared among incoming connections. When the property is set, the corresponding value is set for incoming connections as they are accepted. Existing connections are not modified.

Listening Property (SSHTunnel Class)

If set to True, the class accepts incoming connections on LocalPort.

Syntax


public boolean isListening();


public void setListening(boolean listening);

Default Value

False

Remarks

This property indicates whether the class is listening for connections on the port specified by the LocalPort property.

Note: Use the StartListening and StopListening methods to control whether the class is listening.

This property is not available at design time.

LocalHost Property (SSHTunnel Class)

The name of the local host or user-assigned IP interface through which connections are initiated or accepted.

Syntax


public String getLocalHost();


public void setLocalHost(String localHost);

Default Value

Remarks

The LocalHost property contains the name of the local host as obtained by the gethostname() system call, or if the user has assigned an IP address, the value of that address.

In multi-homed hosts (machines with more than one IP interface) setting LocalHost to the value of an interface will make the class initiate connections (or accept in the case of server classs) only through that interface.

If the class is connected, the LocalHost property shows the IP address of the interface through which the connection is made in internet dotted format (aaa.bbb.ccc.ddd). In most cases, this is the address of the local host, except for multi-homed hosts (machines with more than one IP interface).

NOTE: LocalHost is not persistent. You must always set it in code, and never in the property window.

LocalPort Property (SSHTunnel Class)

The TCP port in the local host where the class binds.

Syntax


public int getLocalPort();


public void setLocalPort(int localPort);

Default Value

Remarks

This property must be set before the class can start listening. If its value is 0, then the TCP/IP subsystem picks a port number at random. The port number can be found by checking the value of this property after the class is listening (i.e., after successfully assigning True to the Listening property).

The service port is not shared among servers so two classs cannot be listening on the same port at the same time.

This property must be set before a connection is attempted. It instructs the class to bind to a specific port (or communication endpoint) in the local machine.

Setting this property to 0 (default) enables the system to choose an open port at random. The chosen port will be returned by the LocalPort property after the connection is established.

LocalPort cannot be changed once a connection is made. Any attempt to set this property when a connection is active will generate an error.

This property is useful when trying to connect to services that require a trusted port in the client side.

SSHAcceptServerHostKey Property (SSHTunnel Class)

Instructs the class to accept the server host key that matches the supplied key.

Syntax


public Certificate getSSHAcceptServerHostKey();


public void setSSHAcceptServerHostKey(Certificate SSHAcceptServerHostKey);

Remarks

If the host key that will be used by the server is known in advance, this property may be set to accept the expected key. Otherwise the SSHServerAuthentication event should be trapped, and the key should be accepted or refused in the event.

If this property is not set and the SSHServerAuthentication event is not trapped, the server will not be authenticated and the connection will be terminated by the client.

Please refer to the Certificate type for a complete list of fields.

SSHAuthMode Property (SSHTunnel Class)

The authentication method to be used the class when calling SSHLogon .

Syntax


public int getSSHAuthMode();


public void setSSHAuthMode(int SSHAuthMode);


Enumerated values:
  public final static int amNone = 0;
  public final static int amMultiFactor = 1;
  public final static int amPassword = 2;
  public final static int amPublicKey = 3;
  public final static int amKeyboardInteractive = 4;
  public final static int amGSSAPIWithMic = 5;
  public final static int amCustom = 6;
  public final static int amGSSAPIKeyex = 7;

Default Value

Remarks

The SSH Authentication specification (RFC 4252) specifies multiple methods by which a user can be authenticated by an SSH server. When a call is made to SSHLogon, the class will connect to the SSH server and establish the security layer. After the connection has been secured, the client will send an authentication request to the SSHHost containing the SSHUser. The server will respond containing a list of methods by which that user may be authenticated.

The class will attempt to authenticate the user by one of those methods based on the value of SSHAuthMode and other property values supplied by the user. Currently, the class supports the following authentication methods:


`amNone` (0)	No authentication will be performed. The current SSHUser value is ignored, and the connection will be logged in as anonymous.
`amMultiFactor` (1)	This allows the class to attempt a multi-step authentication process. The class will send authentication data to the server based on the list of methods allowed for the current user and the authentication property values supplied. The class will continue to send authentication data until the server acknowledges authentication success. If the server rejects an authentication step, the class throws an exception.
`amPassword` (2)	The class will use the values of SSHUser and SSHPassword to authenticate the user.
`amPublicKey` (3)	The class will use the values of SSHUser and SSHCert to authenticate the user. SSHCert must have a private key available for this authentication method to succeed.
`amKeyboardInteractive` (4)	At the time of authentication, the class will fire the SSHKeyboardInteractive event containing instructions on how to complete the authentication step. (NOTE: `amKeyboardInteractive` is not supported in SSHTunnel).
`amGSSAPIWithMic` (5)	This allows the class to attempt Kerberos authentication using the GSSAPI-WITH-MIC scheme. The client will try Kerberos authentication using the value of SSHUser (single sign-on), or if SSHPassword is specified as well, it will try Kerberos authentication with alternate credentials. This is currently supported only on Windows, unless using the Java edition, which also provides support for Linux and macOS.
`amCustom` (6)	This allows the class caller to take over the authentication process completely. When amCustom is set, the class will fire the SSHCustomAuth event as necessary to complete the authentication process.
`amGSSAPIKeyex` (7)	This allows the class to attempt Kerberos authentication using the GSSAPIKeyex scheme. The client will try Kerberos authentication using the value of SSHUser (single sign-on), or if SSHPassword is specified as well, it will try Kerberos authentication with alternate credentials. This is currently supported only on Windows, unless using the Java edition, which also provides support for Linux and macOS.

Example (User/Password Auth): Control.SSHAuthMode = SftpSSHAuthModes.amPassword Control.SSHUser = "username" Control.SSHPassword = "password" Control.SSHLogon("server", 22) Example (Public Key Auth): Control.SSHAuthMode = SftpSSHAuthModes.amPublicKey Control.SSHUser = "username" Control.SSHCert = New Certificate(CertStoreTypes.cstPFXFile, "cert.pfx", "certpassword", "*") Control.SSHLogon("server", 22)

SSHCert Property (SSHTunnel Class)

A certificate to be used for authenticating the SSHUser .

Syntax


public Certificate getSSHCert();


public void setSSHCert(Certificate SSHCert);

Remarks

In order to use public key authentication, SSHCert must contain a Certificate with a valid private key. The certificate's public key value is sent to the server along with a signature produced using the private key. The server will first check to see if the public key values match what is known for the user, and then will attempt to use those values to verify the signature.

Please refer to the Certificate type for a complete list of fields.

SSHCompressionAlgorithms Property (SSHTunnel Class)

A comma-separated list containing all allowable compression algorithms.

Syntax


public String getSSHCompressionAlgorithms();


public void setSSHCompressionAlgorithms(String SSHCompressionAlgorithms);

Default Value

"none,zlib"

Remarks

During the SSH handshake, this list will be used to negotiate the compression algorithm to be used between the client and server. This list is used for both directions: client to server and server to client. When negotiating algorithms, each side sends a list of all algorithms it supports or allows. The algorithm chosen for each direction is the first algorithm to appear in the sender's list that the receiver supports, so it is important to list multiple algorithms in preferential order. If no algorithm can be agreed upon, the class will raise an error and the connection will be aborted.

At least one supported algorithm must appear in this list. The following compression algorithms are supported by the class:

zlib
zlib@openssh.com
none

SSHEncryptionAlgorithms Property (SSHTunnel Class)

A comma-separated list containing all allowable encryption algorithms.

Syntax


public String getSSHEncryptionAlgorithms();


public void setSSHEncryptionAlgorithms(String SSHEncryptionAlgorithms);

Default Value

"aes256-ctr,aes192-ctr,aes128-ctr,aes256-cbc,aes192-cbc,aes128-cbc,3des-ctr,3des-cbc,blowfish-cbc,arcfour256,arcfour128,arcfour,cast128-cbc,aes256-gcm@openssh.com,aes128-gcm@openssh.com,chacha20-poly1305@openssh.com"

Remarks

During the SSH handshake, this list will be used to negotiate the encryption algorithm to be used between the client and server. This list is used for both directions: client to server and server to client. When negotiating algorithms, each side sends a list of all algorithms it supports or allows. The algorithm chosen for each direction is the first algorithm to appear in the sender's list that the receiver supports, so it is important to list multiple algorithms in preferential order. If no algorithm can be agreed upon, the class will raise an error and the connection will be aborted.

At least one supported algorithm must appear in this list. The following encryption algorithms are supported by the class:


`aes256-ctr`	256-bit AES encryption in CTR mode
`aes256-cbc`	256-bit AES encryption in CBC mode
`aes192-ctr`	192-bit AES encryption in CTR mode
`aes192-cbc`	192-bit AES encryption in CBC mode
`aes128-ctr`	128-bit AES encryption in CTR mode
`aes128-cbc`	128-bit AES encryption in CBC mode
`3des-ctr`	192-bit (3-key) triple DES encryption in CTR mode
`3des-cbc`	192-bit (3-key) triple DES encryption in CBC mode
`cast128-cbc`	CAST-128 encryption
`blowfish-cbc`	Blowfish encryption
`arcfour`	ARC4 encryption
`arcfour128`	128-bit ARC4 encryption
`arcfour256`	256-bit ARC4 encryption
`aes256-gcm@openssh.com`	256-bit AES encryption in GCM mode.
`aes128-gcm@openssh.com`	128-bit AES encryption in GCM mode.
`chacha20-poly1305@openssh.com`	ChaCha20 with Poly1305-AES encryption.

SSHForwardHost Property (SSHTunnel Class)

The address of the remote host. Domain names are resolved to IP addresses.

Syntax


public String getSSHForwardHost();


public void setSSHForwardHost(String SSHForwardHost);

Default Value

Remarks

The SSHForwardHost property specifies the IP address (IP number in dotted internet format) or Domain Name of the remote host. It is set before a connection is attempted and cannot be changed once a connection is established.

If the SSHForwardHost property is set to a Domain Name, a DNS request is initiated, and upon successful termination of the request, the SSHForwardHost property is set to the corresponding address. If the search is not successful, an error is returned.

If the class is configured to use a SOCKS firewall, the value assigned to this property may be preceded with an "*". If this is the case, the host name is passed to the firewall unresolved and the firewall performs the DNS resolution.

SSHForwardPort Property (SSHTunnel Class)

The TCP port in the remote host.

Syntax


public int getSSHForwardPort();


public void setSSHForwardPort(int SSHForwardPort);

Default Value

Remarks

The SSHForwardPort property specifies a service port on the remote host to connect to.

A valid port number (a value between 1 and 65535) is required for the connection to take place. The property must be set before a connection is attempted and cannot be changed once a connection is established. Any attempt to change this property while connected will fail with an error.

SSHHost Property (SSHTunnel Class)

The address of the SSH host.

Syntax


public String getSSHHost();


public void setSSHHost(String SSHHost);

Default Value

Remarks

The SSHHost property specifies the IP address (IP number in dotted internet format) or Domain Name of the remote host. It is set before a connection is attempted and cannot be changed once a connection is established.

If the SSHHost property is set to a Domain Name, a DNS request is initiated, and upon successful termination of the request, the SSHHost property is set to the corresponding address. If the search is not successful, an error is returned.

The SSHHost must be the same host that will be assumed for SSH as for the remote service being connected to.

SSHPassword Property (SSHTunnel Class)

The password for SSH password-based authentication.

Syntax


public String getSSHPassword();


public void setSSHPassword(String SSHPassword);

Default Value

Remarks

SSHPassword specifies the password which is used to authenticate the client to the SSH server.

SSHPort Property (SSHTunnel Class)

The port on the SSH server where the SSH service is running; by default, 22.

Syntax


public int getSSHPort();


public void setSSHPort(int SSHPort);

Default Value

Remarks

The SSHPort specifies a service port on the SSH host to connect to.

SSHUser Property (SSHTunnel Class)

The username for SSH authentication.

Syntax


public String getSSHUser();


public void setSSHUser(String SSHUser);

Default Value

Remarks

SSHUser specifies the username which is used to authenticate the client to the SSH server. This property is required.

Config Method (Sshtunnel Class)

Sets or retrieves a configuration setting.

Syntax

public String config(String configurationString);

Remarks

Config is a generic method available in every class. It is used to set and retrieve configuration settings for the class.

These settings are similar in functionality to properties, but they are rarely used. In order to avoid "polluting" the property namespace of the class, access to these internal properties is provided through the Config method.

To set a configuration setting named PROPERTY, you must call Config("PROPERTY=VALUE"), where VALUE is the value of the setting expressed as a string. For boolean values, use the strings "True", "False", "0", "1", "Yes", or "No" (case does not matter).

To read (query) the value of a configuration setting, you must call Config("PROPERTY"). The value will be returned as a string.

Connect Method (Sshtunnel Class)

Connects to the SSH host without logging in.

Syntax

public void connect();

Remarks

This method establishes a connection with the SSHHost but does not log in. In most cases it is recommended to use the StartListening method which will both establish a connection and log in to the server.

This method may be useful in cases where it is desirable to separate the connection and logon operations, for instance confirming a host is available by first creating the connection.

DecodePacket Method (Sshtunnel Class)

Decodes a hex-encoded SSH packet.

Syntax

public byte[] decodePacket(String encodedPacket);

Remarks

This method is used to decode an SSH packet created by EncodePacket.

Note: This method is only applicable for reading and creating SSH packets for use within the SSHCustomAuth event.

Disconnect Method (Sshtunnel Class)

This method disconnects the specified client.

Syntax

public void disconnect(String connectionId);

Remarks

This method immediately disconnects from the server without first logging off.

In most cases the StopListening method should be used to logoff and disconnect from the server. Call the Disconnect method in cases where it is desirable to immediately disconnect without first logging off.

Calling this method will disconnect the client specified by the ConnectionId parameter.

DoEvents Method (Sshtunnel Class)

Processes events from the internal message queue.

Syntax

public void doEvents();

Remarks

When DoEvents is called, the class processes any available events. If no events are available, it waits for a preset period of time, and then returns.

EncodePacket Method (Sshtunnel Class)

Hex encodes an SSH packet.

Syntax

public String encodePacket(byte[] packet);

Remarks

This method is used to encode a raw SSH packet created by SetSSHParam.

Note: This method is only applicable for reading and creating SSH packets for use within the SSHCustomAuth event.

GetSSHParam Method (Sshtunnel Class)

Used to read a field from an SSH packet's payload.

Syntax

public String getSSHParam(byte[] payload, String field);

Remarks

This method is used to read the value of a particular field from an SSH packet's payload. Payload should contain the full payload of a packet received by an event such as SSHChannelRequest. Field is the name of a field to be read out of the packet.

The following is a list of the names of well-known channel request field names and their encodings:


ChannelId (`int32`)	The id of the channel that received the packet.
RequestType (`string`)	The type of channel request.
WantsReply (`boolean`)	Whether or not the client wants a reply to the request.

The remaining fields that are available in the payload are dependent upon the value of RequestType.

pty-req

Pty-req is a request to open a pseudo terminal on the specified channel. The following fields are available:


TerminalType (`string`)	The type of terminal being requested (eg: "vt100").
TerminalWidthCharacters (`int32`)	The width, in characters, of the terminal to be opened.
TerminalHeightRows (`int32`)	The height, in rows, of the terminal to be opened.
TerminalWidthPixels (`int32`)	The width, in pixels, of the terminal to be opened.
TerminalHeightPixels (`int32`)	The height, in pixels, of the terminal to be opened.
TerminalModes (`string`)	A list of op-val (int32-byte) encoded modes to be used by the terminal.

x11-req

X11-req is a request to forward x11 sessions over a channel. The following fields are available:


SingleConnection (`boolean`)	Disallows more than one connection to be forwarded by the channel.
X11AuthProtocol (`string`)	The authentication protocol to be used (eg: "MIT-MAGIC-COOKIE-1").
X11AuthCookie (`string`)	A hexadecimal-encoded cookie to be used for authentication.
X11ScreenNumber (`int32`)	The x11 screen number to be used.

env

Env is a request to set an environment variable to be passed into a shell that may be started later. The following fields are available:


VariableName (`string`)	The name of the variable to be set.
VariableValue (`string`)	The value of the variable to be set.

exec

Exec is a request to execute a command on the channel using the authenticated user's shell. The following field is available:


Command (`string`)	The command to be executed.

subsystem

Subsystem is a request to start a subsystem on the specified channel. The following field is available:


Subsystem (`string`)	The name of the subsystem to be started (eg: "sftp").

xon-xoff

Instructs the server to allow or disallow control-S/control-Q style flow control. The following field is available:


ClientCanDo (`boolean`)	Whether or not the server should enable flow control.

signal

Sends a signal to the remote process/service. The following field is available:


SignalName (`string`)	The name of the signal to be sent.

If the packet type is not well known, Field should start with the special character "%" and contain a comma-separated list of field types as defined in SetSSHParam. For example, reading out the X11AuthProtocol of an x11-req payload, you can use "%s,f".

Note: the return value is a string encoded the same way as the FieldValue param in SetSSHParam.

Note: This method is only applicable for reading and creating SSH packets for use within the SSHCustomAuth event.

GetSSHParamBytes Method (Sshtunnel Class)

Used to read a field from an SSH packet's payload.

Syntax

public byte[] getSSHParamBytes(byte[] payload, String field);

Remarks

This method is the same as calling GetSSHParam, but returns raw bytes instead of strings.

Note: This method is only applicable for reading and creating SSH packets for use within the SSHCustomAuth event.

Reset Method (Sshtunnel Class)

Reset the class.

Syntax

public void reset();

Remarks

This method will reset the class's properties to their default values.

SetSSHParam Method (Sshtunnel Class)

Used to write a field to the end of a payload.

Syntax

public byte[] setSSHParam(byte[] payload, String fieldType, String fieldValue);

Remarks

This method is used to build the payload portion of an SSH packet to be sent later by a call to SendSSHPacket. Payload should contain the result of a previous call to SetSSHParam. FieldType is a string defining the type of field to be written to the packet. FieldValue should be the string representation of the field to be written.

The following is a list of supported field types and a description of how FieldValue should be encoded:


s	A plaintext string containing the default system encoding of the data.
sb	A string containing the hex encoded data. (eg: "A1B23C")
m	A variable-length large integer, encoded as a textual representation of the value ("1234").
i	A 32-bit integer, encoded as a textual representation of the value (eg: "1234").
l	A 64-bit integer, encoded as a textual representation of the value (eg: "1234").
b	A single byte, encoded as a textual representation of the value (eg: "123").
f	A boolean flag, encoded as a textual representation of the value (eg: 'true' or 'false')

Note: integer values may be encoded in hexadecimal by prefixing "0x" to the beginning of the string, otherwise the value is assumed to be base-10.

Note: This method is only applicable for reading and creating SSH packets for use within the SSHCustomAuth event.

Shutdown Method (Sshtunnel Class)

This method shuts down the server.

Syntax

public void shutdown();

Remarks

This method shuts down the server. Calling this method is equivalent to calling StopListening and then breaking every client connection by calling Disconnect.

StartListening Method (Sshtunnel Class)

This method starts listening for incoming connections.

Syntax

public void startListening();

Remarks

This method begins listening for incoming connections on the port specified by LocalPort. Once listening, events will fire as new clients connect and data are transferred.

To stop listening for new connections, call StopListening. To stop listening for new connections and to disconnect all existing clients, call Shutdown.

StopListening Method (Sshtunnel Class)

This method stops listening for new connections.

Syntax

public void stopListening();

Remarks

This method stops listening for new connections. After being called, any new connection attempts will be rejected. Calling this method does not disconnect existing connections.

To stop listening and to disconnect all existing clients, call Shutdown instead.

Connected Event (Sshtunnel Class)

This event is fired immediately after a connection completes (or fails).

Syntax

public class DefaultSshtunnelEventListener implements SshtunnelEventListener {
  ...
  public void connected(SshtunnelConnectedEvent e) {}
  ...
}

public class SshtunnelConnectedEvent {
  public String connectionId;
  public int statusCode;
  public String description;
}

Remarks

If the connection is made normally, StatusCode is 0, and Description is "OK".

If the connection fails, StatusCode has the error code returned by the system. Description contains a description of this code. The value of StatusCode is equal to the value of the system error.

Please refer to the Error Codes section for more information.

ConnectionRequest Event (Sshtunnel Class)

This event is fired when a request for connection comes from a remote host.

Syntax

public class DefaultSshtunnelEventListener implements SshtunnelEventListener {
  ...
  public void connectionRequest(SshtunnelConnectionRequestEvent e) {}
  ...
}

public class SshtunnelConnectionRequestEvent {
  public String address;
  public int port;
  public boolean accept;
}

Remarks

This event indicates an incoming connection. The connection is accepted by default. Address and Port will contain information about the remote host requesting the inbound connection. If you want to refuse it, you can set the Accept parameter to False.

DataIn Event (Sshtunnel Class)

This event is fired when data come in.

Syntax

public class DefaultSshtunnelEventListener implements SshtunnelEventListener {
  ...
  public void dataIn(SshtunnelDataInEvent e) {}
  ...
}

public class SshtunnelDataInEvent {
  public String connectionId;
  public byte[] text;
  public boolean EOL;
}

Remarks

Trapping the DataIn event is your only chance to get the data coming from the other end of the connection specified by ConnectionId. The incoming data are provided through the Text parameter.

EOL indicates whether or not the EOL string was found at the end of Text. If the EOL string was found, then EOL is True.

If Text is part of the data portion of length larger than either DefaultMaxLineLength or MaxLineLength with no EOL strings in it, then EOL is False. Please note that this means that one or more DataIn events with EOL set to False can be received during a connection.

If the EOL property is "" (empty string), then EOL can be disregarded (it is always True).

Note: Events are not re-entrant. Performing time-consuming operations within this event will prevent it from firing again in a timely manner and may affect overall performance.

Disconnected Event (Sshtunnel Class)

Fired when a connection is closed.

Syntax

public class DefaultSshtunnelEventListener implements SshtunnelEventListener {
  ...
  public void disconnected(SshtunnelDisconnectedEvent e) {}
  ...
}

public class SshtunnelDisconnectedEvent {
  public String connectionId;
  public int statusCode;
  public String description;
}

Remarks

If the connection is broken normally, StatusCode is 0, and Description is "OK".

If the connection is broken for any other reason, StatusCode has the error code returned by the system. Description contains a description of this code. The value of StatusCode is equal to the value of the system error.

Please refer to the Error Codes section for more information.

Note: When the class is disconnected from the SSH server for any reason the ConnectionId parameter will be -1.

Error Event (Sshtunnel Class)

Information about errors during data delivery.

Syntax

public class DefaultSshtunnelEventListener implements SshtunnelEventListener {
  ...
  public void error(SshtunnelErrorEvent e) {}
  ...
}

public class SshtunnelErrorEvent {
  public String connectionId;
  public int errorCode;
  public String description;
}

Remarks

The Error event is fired in case of exceptional conditions during message processing. Normally the class throws an exception.

ConnectionId contains an error code and Description contains a textual description of the error. For a list of valid error codes and their descriptions, please refer to the Error Codes section.

ErrorCode contains an error code and Description contains a textual description of the error. For a list of valid error codes and their descriptions, please refer to the Error Codes section.

Log Event (Sshtunnel Class)

Fires once for each log message.

Syntax

public class DefaultSshtunnelEventListener implements SshtunnelEventListener {
  ...
  public void log(SshtunnelLogEvent e) {}
  ...
}

public class SshtunnelLogEvent {
  public int logLevel;
  public String message;
  public String logType;
}

Remarks

This event fires once for each log messages generated by the class. The verbosity is controlled by the LogLevel setting.

LogLevel indicates the detail level of the message. Possible values are:


0 (None)	No messages are logged.
1 (Info - Default)	Informational events such as SSH handshake messages are logged.
2 (Verbose)	Detailed data such as individual packet information is logged.
3 (Debug)	Debug data including all relevant sent and received bytes are logged.

Message is the log message.

LogType is reserved for future use.

ReconnectAttempt Event (Sshtunnel Class)

Fires when attempting to reconnect.

Syntax

public class DefaultSshtunnelEventListener implements SshtunnelEventListener {
  ...
  public void reconnectAttempt(SshtunnelReconnectAttemptEvent e) {}
  ...
}

public class SshtunnelReconnectAttemptEvent {
  public String host;
  public int port;
  public int retryCount;
  public int retriesRemaining;
  public int maxRetryCount;
  public int retryInterval;
  public int retryType;
  public int remoteListeningPort;
  public boolean cancel;
}

Remarks

This event fires both when attempting to reconnect to the SSHHost and when re-establishing a SSH tunnel.

Only applicable when AutoReconnect is enabled. To determine which type of connection is being established check the RetryType parameter.

The following table provides details about the parameters.


Host	The SSH host to which the connection is attempted.
Port	The Port on the SSH host to which the connection is attempted.
RetryCount	The current retry attempt. For instance, this may be attempt number 2 out of 5, then RetryCount will hold the value `2`.
RetriesRemaining	The number of retries remaining after this attempt. This number does not include the current attempt. If MaxRetryCount is set to unlimited this will return `-1`.
MaxRetryCount	The maximum number of retries as specified in MaxRetryCount.
RetryInterval	The interval (in seconds) between retry attempts as specified in RetryInterval.
RetryType	The type of connection being retried. Possible values are: `0` - SSH `1` - Tunnel
RemoteListeningPort	The port on the SSH host which the reverse tunnel will use. This is only applicable when RetryType is `1`.
Cancel	Maybe set within this event to cancel the retry attempts. If set to `True` no further retry attempts will be executed.

SSHCustomAuth Event (Sshtunnel Class)

Fired when the class is doing custom authentication.

Syntax

public class DefaultSshtunnelEventListener implements SshtunnelEventListener {
  ...
  public void SSHCustomAuth(SshtunnelSSHCustomAuthEvent e) {}
  ...
}

public class SshtunnelSSHCustomAuthEvent {
  public String packet;
}

Remarks

SSHCustomAuth is fired during the user authentication stage of the SSH logon process if SSHAuthMode is set to amCustom. Packet contains the raw last SSH packet sent by the server, in HEX-encoded format.

The client should create a new raw SSH packet to send to the server and set Packet to the HEX-encoded representation of the packet to send.

In all cases, Packet will start with the message type field.

To read the incoming packet call DecodePacket and then use the GetSSHParam and GetSSHParamBytes methods. To create a packet use the SetSSHParam method and then call EncodePacket to obtain a HEX-encoded value and assign this to the Packet parameter.

SSHKeyboardInteractive Event (Sshtunnel Class)

Fired when the class receives a request for user input from the server.

Syntax

public class DefaultSshtunnelEventListener implements SshtunnelEventListener {
  ...
  public void SSHKeyboardInteractive(SshtunnelSSHKeyboardInteractiveEvent e) {}
  ...
}

public class SshtunnelSSHKeyboardInteractiveEvent {
  public String name;
  public String instructions;
  public String prompt;
  public String response;
  public boolean echoResponse;
}

Remarks

SSHKeyboardInteractive is fired during the user authentication stage of the SSH logon process. During authentication, the class will request a list of available authentication methods for the SSHUser. For example, if the SSHHost responds with "keyboard-interactive", the class will fire this event to allow the client application to set the password.

During authentication, the SSH server may respond with a request for the user's authentication information. Name is a server-provided value associated with the authentication method such as "CRYPTOCard Authentication". Instructions will contain specific instructions, also supplied by the server, for how the user should respond.

Along with these values, the server will also send at least one input Prompt to be displayed to and filled out by the user. Response should be set to the user's input, and will be sent back in the user authentication information response. EchoResponse is a server recommendation for whether or not the user's response should be echoed back during input.

Note: the server may send several prompts in a single packet. The class will fire the SSHKeyboardInteractive event once for each prompt.

SSHServerAuthentication Event (Sshtunnel Class)

Fired after the server presents its public key to the client.

Syntax

public class DefaultSshtunnelEventListener implements SshtunnelEventListener {
  ...
  public void SSHServerAuthentication(SshtunnelSSHServerAuthenticationEvent e) {}
  ...
}

public class SshtunnelSSHServerAuthenticationEvent {
  public byte[] hostKey;
  public String fingerprint;
  public String keyAlgorithm;
  public String certSubject;
  public String certIssuer;
  public String status;
  public boolean accept;
}

Remarks

This event is where the client can decide whether to continue with the connection process or not. If the public key is known to be a valid key for the SSH server, Accept should be set to True within the event. Otherwise, the server will not be authenticated and the connection will be broken.

Accept will be True only if either HostKey or Fingerprint is identical to the value of SSHAcceptServerHostKey.

Accept may be set to True manually to accept the server host key.

Note that SSH's security inherently relies on client verification of the host key. Ignoring the host key and always setting Accept to true is strongly discouraged, and could cause potentially serious security vulnerabilities in your application. It is recommended that clients maintain a list of known keys for each server and check HostKey against this list each time a connection is attempted.

Host Key contains the full binary text of the key, in the same format used internally by SSH.

Fingerprint holds the SHA-256 hash of HostKey in the hex-encoded form: 0a:1b:2c:3d. To configure the hash algorithm used to calculate this value see SSHFingerprintHashAlgorithm.

KeyAlgorithm identifies the host key algorithm. Supported values are:

ssh-rsa
ssh-dss
rsa-sha2-256
rsa-sha2-512
x509v3-sign-rsa
x509v3-sign-dss
ecdsa-sha2-nistp256
ecdsa-sha2-nistp384
ecdsa-sha2-nistp521

To limit the accepted host key algorithms refer to SSHPublicKeyAlgorithms.

CertSubject is the subject of the certificate. This is only applicable when KeyAlgorithm is "x509v3-sign-rsa" or "x509v3-sign-dss".

CertIssuer is the issuer of the certificate. This is only applicable when KeyAlgorithm is "x509v3-sign-rsa" or "x509v3-sign-dss".

Status is reserved for future use.

SSHStatus Event (Sshtunnel Class)

Shows the progress of the secure connection.

Syntax

public class DefaultSshtunnelEventListener implements SshtunnelEventListener {
  ...
  public void SSHStatus(SshtunnelSSHStatusEvent e) {}
  ...
}

public class SshtunnelSSHStatusEvent {
  public String message;
}

Remarks

The event is fired for informational and logging purposes only. Used to track the progress of the connection.

Certificate Type

This is the digital certificate being used.

Remarks

This type describes the current digital certificate. The certificate may be a public or private key. The fields are used to identify or select certificates.

Fields

EffectiveDate
String (read-only)
Default Value: ""

This is the date on which this certificate becomes valid. Before this date, it is not valid. The following example illustrates the format of an encoded date:

23-Jan-2000 15:00:00.

Encoded
String
Default Value: ""

This is the certificate (PEM/Base64 encoded). This field is used to assign a specific certificate. The Store and Subject fields also may be used to specify a certificate.

When Encoded is set, a search is initiated in the current Store for the private key of the certificate. If the key is found, Subject is updated to reflect the full subject of the selected certificate; otherwise, Subject is set to an empty string.

EncodedB
byte[]
Default Value: ""

This is the certificate (PEM/Base64 encoded). This field is used to assign a specific certificate. The Store and Subject fields also may be used to specify a certificate.

ExpirationDate
String (read-only)
Default Value: ""

This is the date the certificate expires. After this date, the certificate will no longer be valid. The following example illustrates the format of an encoded date:

23-Jan-2001 15:00:00.

ExtendedKeyUsage
String
Default Value: ""

This is a comma-delimited list of extended key usage identifiers. These are the same as ASN.1 object identifiers (OIDs).

Fingerprint
String (read-only)
Default Value: ""

This is the hex-encoded, 16-byte MD5 fingerprint of the certificate. This property is primarily used for keys which do not have a corresponding X.509 public certificate, such as PEM keys that only contain a private key. It is commonly used for SSH keys.

The following example illustrates the format: bc:2a:72:af:fe:58:17:43:7a:5f:ba:5a:7c:90:f7:02

FingerprintSHA1
String (read-only)
Default Value: ""

This is the hex-encoded, 20-byte SHA-1 fingerprint of the certificate. This property is primarily used for keys which do not have a corresponding X.509 public certificate, such as PEM keys that only contain a private key. It is commonly used for SSH keys.

The following example illustrates the format: 30:7b:fa:38:65:83:ff:da:b4:4e:07:3f:17:b8:a4:ed:80:be:ff:84

FingerprintSHA256
String (read-only)
Default Value: ""

This is the hex-encoded, 32-byte SHA-256 fingerprint of the certificate. This property is primarily used for keys which do not have a corresponding X.509 public certificate, such as PEM keys that only contain a private key. It is commonly used for SSH keys.

The following example illustrates the format: 6a:80:5c:33:a9:43:ea:b0:96:12:8a:64:96:30:ef:4a:8a:96:86:ce:f4:c7:be:10:24:8e:2b:60:9e:f3:59:53

Issuer
String (read-only)
Default Value: ""

This is the issuer of the certificate. This field contains a string representation of the name of the issuing authority for the certificate.

KeyPassword
String
Default Value: ""

This is the password for the certificate's private key (if any).

Some certificate stores may individually protect certificates' private keys, separate from the standard protection offered by the StorePassword. KeyPassword. This field can be used to read such password-protected private keys.

Note: this property defaults to the value of StorePassword. To clear it, you must set the property to the empty string (""). It can be set at any time, but when the private key's password is different from the store's password, then it must be set before calling PrivateKey.

PrivateKey
String (read-only)
Default Value: ""

This is the private key of the certificate (if available). The key is provided as PEM/Base64-encoded data.

Note: The PrivateKey may be available but not exportable. In this case, PrivateKey returns an empty string.

PrivateKeyAvailable
boolean (read-only)
Default Value: False

This field shows whether a PrivateKey is available for the selected certificate. If PrivateKeyAvailable is True, the certificate may be used for authentication purposes (e.g., server authentication).

PrivateKeyContainer
String (read-only)
Default Value: ""

This is the name of the PrivateKey container for the certificate (if available). This functionality is available only on Windows platforms.

PublicKey
String (read-only)
Default Value: ""

This is the public key of the certificate. The key is provided as PEM/Base64-encoded data.

PublicKeyAlgorithm
String
Default Value: ""

This field contains the textual description of the certificate's public key algorithm. The property contains either the name of the algorithm (e.g., "RSA" or "RSA_DH") or an object identifier (OID) string representing the algorithm.

PublicKeyLength
int (read-only)
Default Value: 0

This is the length of the certificate's public key (in bits). Common values are 512, 1024, and 2048.

SerialNumber
String (read-only)
Default Value: ""

This is the serial number of the certificate encoded as a string. The number is encoded as a series of hexadecimal digits, with each pair representing a byte of the serial number.

SignatureAlgorithm
String (read-only)
Default Value: ""

The field contains the text description of the certificate's signature algorithm. The property contains either the name of the algorithm (e.g., "RSA" or "RSA_MD5RSA") or an object identifier (OID) string representing the algorithm.

Store
String
Default Value: "MY"

This is the name of the certificate store for the client certificate.

The StoreType field denotes the type of the certificate store specified by Store. If the store is password protected, specify the password in StorePassword.

Store is used in conjunction with the Subject field to specify client certificates. If Store has a value, and Subject or Encoded is set, a search for a certificate is initiated. Please see the Subject field for details.

Designations of certificate stores are platform dependent.

The following designations are the most common User and Machine certificate stores in Windows:


MY	A certificate store holding personal certificates with their associated private keys.
CA	Certifying authority certificates.
ROOT	Root certificates.

In Java, the certificate store normally is a file containing certificates and optional private keys.

When the certificate store type is PFXFile, this property must be set to the name of the file. When the type is PFXBlob, the property must be set to the binary contents of a PFX file (i.e., PKCS#12 certificate store).

StoreB
byte[]
Default Value: "MY"

This is the name of the certificate store for the client certificate.

The StoreType field denotes the type of the certificate store specified by Store. If the store is password protected, specify the password in StorePassword.

Designations of certificate stores are platform dependent.

The following designations are the most common User and Machine certificate stores in Windows:


MY	A certificate store holding personal certificates with their associated private keys.
CA	Certifying authority certificates.
ROOT	Root certificates.

In Java, the certificate store normally is a file containing certificates and optional private keys.

StorePassword
String
Default Value: ""

If the type of certificate store requires a password, this property is used to specify the password needed to open the certificate store.

StoreType
int
Default Value: 0

This is the type of certificate store for this certificate.

The class supports both public and private keys in a variety of formats. When the cstAuto value is used, the class will automatically determine the type. This field can take one of the following values:


0 (cstUser - default)	For Windows, this specifies that the certificate store is a certificate store owned by the current user. Note: This store type is not available in Java.
1 (cstMachine)	For Windows, this specifies that the certificate store is a machine store. Note: This store type is not available in Java.
2 (cstPFXFile)	The certificate store is the name of a PFX (PKCS#12) file containing certificates.
3 (cstPFXBlob)	The certificate store is a string (binary or Base64-encoded) representing a certificate store in PFX (PKCS#12) format.
4 (cstJKSFile)	The certificate store is the name of a Java Key Store (JKS) file containing certificates. Note: This store type is only available in Java.
5 (cstJKSBlob)	The certificate store is a string (binary or Base64-encoded) representing a certificate store in Java Key Store (JKS) format. Note: this store type is only available in Java.
6 (cstPEMKeyFile)	The certificate store is the name of a PEM-encoded file that contains a private key and an optional certificate.
7 (cstPEMKeyBlob)	The certificate store is a string (binary or Base64-encoded) that contains a private key and an optional certificate.
8 (cstPublicKeyFile)	The certificate store is the name of a file that contains a PEM- or DER-encoded public key certificate.
9 (cstPublicKeyBlob)	The certificate store is a string (binary or Base64-encoded) that contains a PEM- or DER-encoded public key certificate.
10 (cstSSHPublicKeyBlob)	The certificate store is a string (binary or Base64-encoded) that contains an SSH-style public key.
11 (cstP7BFile)	The certificate store is the name of a PKCS#7 file containing certificates.
12 (cstP7BBlob)	The certificate store is a string (binary) representing a certificate store in PKCS#7 format.
13 (cstSSHPublicKeyFile)	The certificate store is the name of a file that contains an SSH-style public key.
14 (cstPPKFile)	The certificate store is the name of a file that contains a PPK (PuTTY Private Key).
15 (cstPPKBlob)	The certificate store is a string (binary) that contains a PPK (PuTTY Private Key).
16 (cstXMLFile)	The certificate store is the name of a file that contains a certificate in XML format.
17 (cstXMLBlob)	The certificate store is a string that contains a certificate in XML format.
18 (cstJWKFile)	The certificate store is the name of a file that contains a JWK (JSON Web Key).
19 (cstJWKBlob)	The certificate store is a string that contains a JWK (JSON Web Key).
21 (cstBCFKSFile)	The certificate store is the name of a file that contains a BCFKS (Bouncy Castle FIPS Key Store). Note: This store type is only available in Java and .NET.
22 (cstBCFKSBlob)	The certificate store is a string (binary or Base64-encoded) representing a certificate store in BCFKS (Bouncy Castle FIPS Key Store) format. Note: This store type is only available in Java and .NET.
23 (cstPKCS11)	The certificate is present on a physical security key accessible via a PKCS#11 interface. To use a security key, the necessary data must first be collected using the CertMgr class. The ListStoreCertificates method may be called after setting CertStoreType to `cstPKCS11`, CertStorePassword to the PIN, and CertStore to the full path of the PKCS#11 DLL. The certificate information returned in the CertList event's `CertEncoded` parameter may be saved for later use. When using a certificate, pass the previously saved security key information as the Store and set StorePassword to the PIN. Code Example. SSH Authentication with Security Key: `certmgr.CertStoreType = CertStoreTypes.cstPKCS11; certmgr.OnCertList += (s, e) => { secKeyBlob = e.CertEncoded; }; certmgr.CertStore = @"C:\Program Files\OpenSC Project\OpenSC\pkcs11\opensc-pkcs11.dll"; certmgr.CertStorePassword = "123456"; //PIN certmgr.ListStoreCertificates(); sftp.SSHCert = new Certificate(CertStoreTypes.cstPKCS11, secKeyBlob, "123456", "*"); sftp.SSHUser = "test"; sftp.SSHLogon("myhost", 22);`
99 (cstAuto)	The store type is automatically detected from the input data. This setting may be used with both public and private keys and can detect any of the supported formats automatically.

Subject
String
Default Value: ""

This is the subject of the certificate used for client authentication.

This field will be populated with the full subject of the loaded certificate. When loading a certificate the subject is used to locate the certificate in the store.

If an exact match is not found, the store is searched for subjects containing the value of the property.

If a match is still not found, the property is set to an empty string, and no certificate is selected.

The special value "*" picks a random certificate in the certificate store.

The certificate subject is a comma-separated list of distinguished name fields and values. For instance, "CN=www.server.com, OU=test, C=US, E=support@nsoftware.com". Common fields and their meanings are as follows:


Field	Meaning
CN	Common Name. This is commonly a hostname like www.server.com.
O	Organization
OU	Organizational Unit
L	Locality
S	State
C	Country
E	Email Address

If a field value contains a comma, it must be quoted.

SubjectAltNames
String (read-only)
Default Value: ""

This field contains comma-separated lists of alternative subject names for the certificate.

ThumbprintMD5
String (read-only)
Default Value: ""

This field contains the MD5 hash of the certificate. It is primarily used for X.509 certificates. If the hash does not already exist, it is automatically computed.

ThumbprintSHA1
String (read-only)
Default Value: ""

This field contains the SHA-1 hash of the certificate. It is primarily used for X.509 certificates. If the hash does not already exist, it is automatically computed.

ThumbprintSHA256
String (read-only)
Default Value: ""

This field contains the SHA-256 hash of the certificate. It is primarily used for X.509 certificates. If the hash does not already exist, it is automatically computed.

Usage
String
Default Value: ""

This field contains the text description of UsageFlags.

This value will be of one or more of the following strings and will be separated by commas:

Digital Signatures
Key Authentication
Key Encryption
Data Encryption
Key Agreement
Certificate Signing
Key Signing

If the provider is OpenSSL, the value is a comma-separated list of X.509 certificate extension names.

UsageFlags
int
Default Value: 0

This field contains the flags that show intended use for the certificate. The value of UsageFlags is a combination of the following flags:


0x80	Digital Signatures
0x40	Key Authentication (Non-Repudiation)
0x20	Key Encryption
0x10	Data Encryption
0x08	Key Agreement
0x04	Certificate Signing
0x02	Key Signing

Please see the Usage field for a text representation of UsageFlags.

This functionality currently is not available when the provider is OpenSSL.

Version
String (read-only)
Default Value: ""

This field contains the certificate's version number. The possible values are the strings "V1", "V2", and "V3".

Constructors

public Certificate();

Creates a Certificate instance whose properties can be set. This is useful for use with CERTMGR when generating new certificates.

public Certificate( certificateFile);

Opens CertificateFile and reads out the contents as an X.509 public key.

public Certificate( certificateData);

Parses CertificateData as an X.509 public key.

public Certificate( certStoreType,  store,  storePassword,  subject);

CertStoreType identifies the type of certificate store to use. See StoreType for descriptions of the different certificate stores. Store is a file containing the certificate store. StorePassword is the password used to protect the store. After the store has been successfully opened, the class will attempt to find the certificate identified by Subject . This can be either a complete or a substring match of the X.509 certificate's subject Distinguished Name (DN).

public Certificate( certStoreType,  store,  storePassword,  subject,  configurationString);

CertStoreType identifies the type of certificate store to use. See StoreType for descriptions of the different certificate stores. Store is a file containing the certificate store. StorePassword is the password used to protect the store. ConfigurationString is a newline separated list of name-value pairs that may be used to modify the default behavior. Possible values include "PersistPFXKey", which shows whether or not the PFX key is persisted after performing operations with the private key. This correlates to the PKCS12_NO_PERSIST_KEY CryptoAPI option. The default value is True (the key is persisted). "Thumbprint" - an MD5, SHA-1, or SHA-256 thumbprint of the certificate to load. When specified, this value is used to select the certificate in the store. This is applicable to cstUser, cstMachine, cstPublicKeyFile, and cstPFXFile store types. "UseInternalSecurityAPI" shows whether the platform (default) or the internal security API is used when performing certificate-related operations. After the store has been successfully opened, the class will attempt to find the certificate identified by Subject . This can be either a complete or a substring match of the X.509 certificate's subject Distinguished Name (DN).

public Certificate( certStoreType,  store,  storePassword,  encoded);

CertStoreType identifies the type of certificate store to use. See StoreType for descriptions of the different certificate stores. Store is a file containing the certificate store. StorePassword is the password used to protect the store. After the store has been successfully opened, the class will load Encoded as an X.509 certificate and search the opened store for a corresponding private key.

public Certificate( certStoreType,  storeBlob,  storePassword,  subject);

CertStoreType identifies the type of certificate store to use. See StoreType for descriptions of the different certificate stores. StoreBlob is a string (binary- or Base64-encoded) containing the certificate data. StorePassword is the password used to protect the store. After the store has been successfully opened, the class will attempt to find the certificate identified by Subject . This can be either a complete or a substring match of the X.509 certificate's subject Distinguished Name (DN).

public Certificate( certStoreType,  storeBlob,  storePassword,  subject,  configurationString);

public Certificate( certStoreType,  storeBlob,  storePassword,  encoded);

CertStoreType identifies the type of certificate store to use. See StoreType for descriptions of the different certificate stores. Store is a string (binary- or Base64-encoded) containing the certificate store. StorePassword is the password used to protect the store. After the store has been successfully opened, the class will load Encoded as an X.509 certificate and search the opened store for a corresponding private key.

Connection Type

This is a currently connected client.

Remarks

This type describes the connection of a client that is currently connected to the class. You may use the different fields of this type to manage the connection.

Fields

AcceptData
boolean
Default Value: True

Setting this field to false temporarily disables data reception (and the DataIn event) for the connection. Setting this to true re-enables data reception.

Note: It is recommended to use the PauseData or ProcessData method instead of setting this property.

BytesSent
int (read-only)
Default Value: 0

This field shows how many bytes were sent after the last assignment to DataToSend. Please check DataToSend for more information.

Note: This field will always return 0 when the class is operating in the synchronous mode (i.e., the Timeout property is set to a positive value).

Connected
boolean
Default Value: False

This field is used to disconnect individual connections or to show their status.

The Connected field may be set to false to close the connection.

Connected also shows the status of a particular connection (connected/disconnected).

How and when the connection is closed is controlled by the Linger property. Please refer to its description for more information.

Note: It is recommended to use the Disconnect method instead of setting this property.

ConnectionId
String (read-only)
Default Value: ""

This field contains an identifier generated by the class to identify each connection. This identifier is unique to this connection.

DataToSend
String
Default Value: ""

This field contains a string of data to be sent to the remote host. It is a write-only property.

Assigning a string to the DataToSend makes the class send the string to the remote host. The Send method provides similar functionality.

When Timeout is set to 0 and SSLEnabled is set to False, the class will behave asynchronously. If you are sending data to the remote host faster than it can process it, or faster than the network's bandwidth allows, the outgoing queue might fill up. When this happens, the operation fails with exception 10035: "[10035] Operation would block" (WSAEWOULDBLOCK). You can check this error, and then try to send the data again. . The BytesSent property shows how many bytes were sent (if any). If 0 bytes were sent, then you can wait for the ReadyToSend event before attempting to send data again.

Note: The ReadyToSend event is not fired when part of the data is sent successfully.

When SSLEnabled is True or Timeout is set to a positive value, the class behaves synchronously.

Note: It is recommended to use the Send or SendBytes method instead of setting this property.

DataToSendB
byte[]
Default Value: ""

This field contains a string of data to be sent to the remote host. It is a write-only property.

Assigning a string to the DataToSend makes the class send the string to the remote host. The Send method provides similar functionality.

Note: The ReadyToSend event is not fired when part of the data is sent successfully.

When SSLEnabled is True or Timeout is set to a positive value, the class behaves synchronously.

Note: It is recommended to use the Send or SendBytes method instead of setting this property.

EOL
String
Default Value: ""

The EOL field is used to define boundaries in the input stream using the value of the field.

The EOL field is especially useful with ASCII files. By setting it to CRLF ("\r\n") , the incoming ASCII text stream can be split into lines. In this case, one event is fired for each line received (as well as in packet boundaries). The CRLF ("\r\n") . bytes are discarded.

The EOL field is a binary string. This means that it can be more than one byte long, and it can contain NULL bytes.

EOLB
byte[]
Default Value: ""

The EOL field is used to define boundaries in the input stream using the value of the field.

The EOL field is a binary string. This means that it can be more than one byte long, and it can contain NULL bytes.

IdleTimeout
int
Default Value: 0

This field contains the idle timeout for this connection. This field is similar to DefaultIdleTimeout but may be set on a per-connection basis to override DefaultIdleTimeout. This field specifies the idle timeout (in seconds) for the connected client. When set to a positive value, the class will disconnect idle clients after the specified timeout.

This applies only to clients that have not sent to received data within the specified number of seconds.

If set to 0 (default), no idle timeout is applied.

Note: DoEvents must be called for the class to check existing connections.

LocalAddress
String (read-only)
Default Value: ""

This field shows the IP address of the interface through which the connection is passing.

LocalAddress is important for multihomed hosts so that it can be used to find the particular network interface through which an individual connection is going.

MaxLineLength
int
Default Value: 2048

This field is the size of an internal buffer that holds received data while waiting for an EOL string.

If an EOL string is found in the input stream before MaxLineLength bytes are received, the DataIn event is fired with the EOL parameter set to True, and the buffer is reset.

If no EOL is found, and MaxLineLength bytes are accumulated in the buffer, the DataIn event is fired with the EOL parameter set to False, and the buffer is reset.

The minimum value for MaxLineLength is 256 bytes. The default value is 2048 bytes.

ReadyToSend
boolean (read-only)
Default Value: False

This indicates whether the class is ready to send data.

This field indicates that the underlying TCP/IP subsystem is ready to accept data. This is True after a client connects but will become False after a failed DataToSend.

After a failed DataToSend, the ReadyToSend event will fire and this field will be True when data can be sent again.

RecordLength
int
Default Value: 0

If set to a positive value, this setting defines the length of the data records to be received. The class will accumulate data until RecordLength is reached and only then will fire the DataIn event with the data of length RecordLength. This allows data to be received as records of known length. This value can be changed at any time, including within the DataIn event.

A value of 0 (default) means this setting is not used.

Note: It is recommended to use the ChangeRecordLength method instead of setting this property.

RemoteHost
String (read-only)
Default Value: ""

This field shows the IP address of the remote host through which the connection is coming.

The connection must be valid or an error will be fired.

RemotePort
int (read-only)
Default Value: 0

This field shows the Transmission Control Protocol (TCP) port on the remote host through which the connection is coming.

The connection must be valid or an error will be fired.

SingleLineMode
boolean
Default Value: False

This field shows the special mode for line-oriented protocols. When SingleLineMode is True, the class treats the incoming data stream as lines separated by carriage return (CR), line feed (LF), or CRLF. The EOL property is ignored.

Timeout
int
Default Value: 0

This field specifies a timeout for the class.

This field defines the timeout when sending data. When SSLEnabled is False, a value of 0 means data will be sent asynchronously and a positive value means data will be sent synchronously. When SSLEnabled is True, all data is sent synchronously regardless of the Timeout value. Please see the following notes for details.

Plaintext

If the Timeout field is set to 0, all operations return immediately, potentially failing with a WOULDBLOCK error if data cannot be sent immediately.

If Timeout is set to a positive value, data is sent in a blocking manner and the class will wait for the operation to complete before returning control. The class will handle any potential WOULDBLOCK errors internally and automatically retry the operation for a maximum of Timeout seconds.

SSL

If the Timeout field is set to 0, all operations will run uninterrupted until successful completion or an error condition is encountered.

If Timeout is set to a positive value, the class will wait for the operation to complete before returning control.

Additional Notes

The class will use DoEvents to enter an efficient wait loop during any potential waiting period, making sure that all system events are processed immediately as they arrive. This ensures that the host application does not "freeze" and remains responsive.

If Timeout expires, and the operation is not yet complete, the class throws an exception.

Please note that by default, all timeouts are inactivity timeouts, i.e. the timeout period is extended by Timeout seconds when any amount of data is successfully sent or received.

The default value for the Timeout field is 0 (asynchronous for plaintext, synchronous for SSL).

UploadStream
java.io.InputStream
Default Value: ""

Setting this field uploads the data in the specified stream to the current connection. The class will automatically close this stream if CloseStreamAfterTransfer is True (default).

Note: It is recommended to use the SetUploadStream method instead of setting this property.

UserData
String
Default Value: ""

The UserData field holds connection-specific user-specified data.

User-specified data may be set or retrieved at any point while the connection is valid. This provides a simple way to associate arbitrary data with a specific connection.

UserDataB
byte[]
Default Value: ""

The UserData field holds connection-specific user-specified data.

User-specified data may be set or retrieved at any point while the connection is valid. This provides a simple way to associate arbitrary data with a specific connection.

Constructors

public Connection();

Firewall Type

The firewall the class will connect through.

Remarks

When connecting through a firewall, this type is used to specify different properties of the firewall, such as the firewall Host and the FirewallType.

Fields

AutoDetect
boolean
Default Value: False

This field tells the class whether or not to automatically detect and use firewall system settings, if available.

Connection information will first be obtained from Java system properties, such as http.proxyHost and https.proxyHost. Java properties may be set in a variety of ways; please consult the Java documentation for information about how firewall and proxy values can be specified.

If no Java system properties define connection information, the class will inspect the Windows registry for connection information that may be present on the system (applicable only on Windows systems).

FirewallType
int
Default Value: 0

This field determines the type of firewall to connect through. The applicable values are as follows:


fwNone (0)	No firewall (default setting).
fwTunnel (1)	Connect through a tunneling proxy. Port is set to 80.
fwSOCKS4 (2)	Connect through a SOCKS4 Proxy. Port is set to 1080.
fwSOCKS5 (3)	Connect through a SOCKS5 Proxy. Port is set to 1080.
fwSOCKS4A (10)	Connect through a SOCKS4A Proxy. Port is set to 1080.

Host
String
Default Value: ""

This field contains the name or IP address of firewall (optional). If a Host is given, the requested connections will be authenticated through the specified firewall when connecting.

If this field is set to a Domain Name, a DNS request is initiated. Upon successful termination of the request, this field is set to the corresponding address. If the search is not successful, the class throws an exception.

Password
String
Default Value: ""

This field contains a password if authentication is to be used when connecting through the firewall. If Host is specified, the User and Password fields are used to connect and authenticate to the given firewall. If the authentication fails, the class throws an exception.

Port
int
Default Value: 0

This field contains the transmission control protocol (TCP) port for the firewall Host. See the description of the Host field for details.

Note: This field is set automatically when FirewallType is set to a valid value. See the description of the FirewallType field for details.

User
String
Default Value: ""

This field contains a user name if authentication is to be used connecting through a firewall. If the Host is specified, this field and Password fields are used to connect and authenticate to the given Firewall. If the authentication fails, the class throws an exception.

Constructors

public Firewall();

Config Settings (Sshtunnel Class)

The class accepts one or more of the following configuration settings. Configuration settings are similar in functionality to properties, but they are rarely used. In order to avoid "polluting" the property namespace of the class, access to these internal properties is provided through the Config method.

SSHTunnel Config Settings

AutoReconnect: Whether to automatically reconnect.

This setting controls automatic recovery of the SSH connection. If logon is disrupted or the channel is closed the component can be configured to attempt reconnection automatically. Possible values are:


Value	Description
0 (None)	Do not automatically reconnect.
1 (Default)	Reconnect if an existing connection is broken.
2 (Always)	Retry the initial logon as well as recover an existing connection.

See MaxRetryCount and RetryInterval for additional related settings.

MaxRetryCount: The maximum number of retries when reconnecting.

This setting defines the maximum number of connection attempts performed when re-establishing a broken connection. This setting only applies when AutoReconnect is enabled. By default, the component will reconnect forever.

RetryInterval: The interval in seconds between reconnect attempts.

This setting specifies the number of seconds between reconnection attempts. This setting only applies when AutoReconnect is enabled. The default value is 5.

ShutdownChannelOnEOF: Whether the client will shutdown the channel after receiving an EOF packet from the remote host.

The default value is False. Set this to True to send the channel close packet when an EOF packet is received.

SSHClient Config Settings

ChannelDataEOL[ChannelId]: Used to break the incoming data stream into chunks.

By default MaxChannelDataLength is 0 and ChannelDataEOL is an empty string. SSHChannelData fires whenever an SSH_MSG_CHANNEL_DATA packet is received.

If MaxChannelDataLength > 0 and ChannelDataEOL is a non-empty string the class will internally buffer data waiting to fire SSHChannelData until either MaxChannelDataLength is reached or ChannelDataEOL is found, whichever comes first. Query ChannelDataEOLFound to know which condition was met. The buffer is reset any time SSHChannelData fires.

ChannelDataEOL and MaxChannelDataLength MUST be set together or unexpected behavior could occur.

ChannelDataEOLFound[ChannelId]: Determines if ChannelDataEOL was found.

If true,then ChannelDataEOL was found. If false, then MaxChannelDataLength was reached.

This config is only valid when queried inside SSHChannelData, MaxChannelDataLength > 0, and ChannelDataEOL is non-empty.

ClientSSHVersionString: The SSH version string used by the class.

This configuration setting specifies the SSH version string used by the class. The default value is "SSH-2.0-IPWorks SSH Client 2022".

Most SSH servers expect the SSH version string to have the expected format "SSH-protocol version-software version". See above for an example.

EnablePageantAuth: Whether to use a key stored in Pageant to perform client authentication.

This setting controls whether Pageant authentication is disabled, enabled, or required. When enabled or required, the class attempts to communicate with PuTTY's ssh-agent, called "Pageant", over shared memory to perform public key authentication. Possible values and the corresponding behavior is described below:


Value	Description
0 (Disabled - default)	No communication with Pageant is attempted.
1 (Enabled)	Pageant authentication is used if available. If Pageant is not running, or does not contain the expected key no error is thrown.
2 (Required)	Only Pageant authentication is used. If Pageant is not running, or does not contain the expected key an error is thrown.

Example enabling Pageant: component.Config("EnablePageantAuth=1"); component.SSHUser = "sshuser"; component.SSHLogon("localhost", 22);

Note: This functionality is only available on Windows.

KerberosDelegation: If true, asks for credentials with delegation enabled during authentication.

The default value is "True". If set to "False", the client will not ask for credentials delegation support during authentication. Note that even if the client asks for delegation, the server/KDC might not grant it and authentication will still succeed.

KerberosRealm: The fully qualified domain name of the Kerberos Realm to use for GSSAPI authentication.

This property may be set to the fully qualified (DNS) name of the kerberos realm (or Windows Active Directory domain name) to use during GSSAPI authentication. This can be used to force authentication with a given realm if the client and server machines are not part of the same domain.

KerberosSPN: The Kerberos Service Principal Name of the SSH host.

This property can be set to specify the Service Principal Name (SPN) associated with the SSH service on the remote host. This will usually be in the form "host/fqdn.of.sshhost[@REALM]". If not specified, the class will assume the SPN is based on the value of the SSHHost property and the kerberos realm used for authentication.

KeyRenegotiationThreshold: Sets the threshold for the SSH Key Renegotiation.

This property allows you to specify the threshold, in the number of bytes, for the SSH Key Renegotiation. The default value for this property is set to 1 GB.

Example (for setting the threshold to 500 MB): SSHComponent.Config("KeyRenegotiationThreshold=524288000")

LogLevel: Specifies the level of detail that is logged.

This setting controls the level of detail that is logged through the Log event. Possible values are:


0 (None)	No messages are logged.
1 (Info - Default)	Informational events such as SSH handshake messages are logged.
2 (Verbose)	Detailed data such as individual packet information is logged.
3 (Debug)	Debug data including all relevant sent and received bytes are logged.

MaxChannelDataLength[ChannelId]: The maximum amount of data to accumulate when no ChannelDataEOL is found.

By default MaxChannelDataLength is 0 and ChannelDataEOL is an empty string. SSHChannelData fires whenever an SSH_MSG_CHANNEL_DATA packet is received.

ChannelDataEOL and MaxChannelDataLength MUST be set together or unexpected behavior could occur.

MaxPacketSize: The maximum packet size of the channel, in bytes.

This setting specifies the maximum size of an individual data packet, in bytes, that can be sent to the sender.

MaxWindowSize: The maximum window size allowed for the channel, in bytes.

This setting specifies how many bytes of channel data can be sent to the sender of this message without adjusting the window. Note that this value may be changed during the connection, but the window size can only be increased, not decreased.

NegotiatedStrictKex: Returns whether strict key exchange was negotiated to be used.

Returns whether strict key exchange (strict kex) was negotiated during the SSH handshake. If strict kex is being used, then this will return "True". If strict kex is not being used, then this will return "False".

component.Config("NegotiatedStrictKex")

PasswordPrompt: The text of the password prompt used in keyboard-interactive authentication.

This setting optionally specifies a pattern to be matched to the prompt received from the server during keyboard-interactive authentication. If a matching prompt is detected the class automatically responds to the prompt with the password specified by SSHPassword.

This provides an easy way to automatically reply to prompts with the password if one is presented by the server. The password will be auto-filled in the Response parameter of the SSHKeyboardInteractive event in the case of a match.

The following special characters are supported for pattern matching:


?	Any single character.
*	Any characters or no characters (e.g., C*t matches Cat, Cot, Coast, Ct).
[,-]	A range of characters (e.g., [a-z], [a], [0-9], [0-9,a-d,f,r-z]).
\	The slash is ignored and exact matching is performed on the next character.

If these characters need to be used as a literal in a pattern, then they must be escaped by surrounding them with brackets []. Note: "]" and "-" do not need to be escaped. See below for the escape sequences:


Character	Escape Sequence
?	[?]
*	[*]
[	[[]
\	[\]

For example, to match the value [Something].txt, specify the pattern [[]Something].txt.

PreferredDHGroupBits: The size (in bits) of the preferred modulus (p) to request from the server.

This may be when using the diffie-hellman-group-exchange-sha1 or diffie-hellman-group-exchange-sha256 key exchange algorithms to control the preferred size, in bits, of the modulus (p) prime number to request from the server. Acceptable values are between 1024 and 8192.

RecordLength: The length of received data records.

If set to a positive value, this setting defines the length of data records to be received. The class will accumulate data until RecordLength is reached and only then fire the DataIn event with data of length RecordLength. This allows data to be received as records of known length. This value can be changed at any time, including within the DataIn event.

The default value is 0, meaning this setting is not used.

ServerSSHVersionString: The remote host's SSH version string.

This will return the remote host's SSH version string, which can help when identifying problematic servers. This configuration setting is read-only.

SignedSSHCert: The CA signed client public key used when authenticating.

When authenticating via public key authentication this setting may be set to the CA signed client's public key. This is useful when the server has been configured to trust client keys signed by a particular CA. For instance: component.Config("SignedSSHCert=ssh-rsa-cert-v01@openssh.com AAAAB3NzaC1yc2EAAAADAQABAAAB..."); The algorithm such as ssh-rsa-cert-v01@openssh.com in the above string is used as part of the authentication process. To use a different algorithm simply change this value. For instance all of the following are acceptable with the same signed public key:

ssh-rsa-cert-v01@openssh.com AAAAB3NzaC1yc2EAAAADAQABAAAB...
rsa-sha2-256-cert-v01@openssh.com AAAAB3NzaC1yc2EAAAADAQABAAAB...
rsa-sha2-512-cert-v01@openssh.com AAAAB3NzaC1yc2EAAAADAQABAAAB...

SSHAcceptAnyServerHostKey: If set the class will accept any key presented by the server.

The default value is "False". Set this to "True" to accept any key presented by the server.

SSHAcceptServerCAKey: The CA public key that signed the server's host key.

If the server's host key was signed by a CA, this setting may be used to specify the CA's public key. If specified the class will trust any server's host key that was signed by the CA. For instance: component.Config("SSHAcceptServerCAKey=ssh-rsa AAAAB3NzaC1yc2EAAAADAQAB...");

SSHAcceptServerHostKeyFingerPrint: The fingerprint of the server key to accept.

This may be set to a comma-delimited collection of 16-byte MD5 fingerprints that should be accepted as the host's key. You may supply it by HEX encoding the values in the form "0a:1b:2c:3d". Example: SSHClient.Config("SSHAcceptServerHostKeyFingerprint=0a:1b:2c:3d"); If the server's fingerprint matches one of the values supplied, the class will accept the host key.

SSHFingerprintHashAlgorithm: The algorithm used to calculate the fingerprint.

This configuration setting controls which hash algorithm is used to calculate the hostkey's fingerprint, displayed when SSHServerAuthentication fires. Valid values are:

MD5
SHA1
SHA256 (default)

SSHFingerprintMD5: The server hostkey's MD5 fingerprint.

This setting may be queried in SSHServerAuthentication to get the server hostkey's MD5 fingerprint.

SSHFingerprintSHA1: The server hostkey's SHA1 fingerprint.

This setting may be queried in SSHServerAuthentication to get the server hostkey's SHA1 fingerprint.

SSHFingerprintSHA256: The server hostkey's SHA256 fingerprint.

This setting may be queried in SSHServerAuthentication to get the server hostkey's SHA256 fingerprint.

SSHKeepAliveCountMax: The maximum number of keep alive packets to send without a response.

This setting specifies the maximum number of keep alive packets to send when no response is received. Normally a response to a keep alive packet is received right away. If no response is received the class will continue to send keep alive packets until SSHKeepAliveCountMax is reached. If this is reached the class will assume the connection is broken and disconnect. The default value is 5.

SSHKeepAliveInterval: The interval between keep alive packets.

This setting specifies the number of seconds between keep alive packets. If set to a positive value the class will send a SSH keep alive packet after KeepAliveInterval seconds of inactivity. This setting only takes effect when there is no activity, if any data is sent or received over the connection it will reset the timer.

The default value is 0 meaning no keep alives will be sent.

Note: The SSHReverseTunnel class uses a default value of 30.

SSHKeyExchangeAlgorithms: Specifies the supported key exchange algorithms.

This may be used to specify the list of supported key exchange algorithms used during SSH negotiation. The value should contain a comma separated list of algorithms. Supported algorithms are:

curve25519-sha256
curve25519-sha256@libssh.org
diffie-hellman-group1-sha1
diffie-hellman-group14-sha1
diffie-hellman-group14-sha256
diffie-hellman-group16-sha512
diffie-hellman-group18-sha512
diffie-hellman-group-exchange-sha256
diffie-hellman-group-exchange-sha1
ecdh-sha2-nistp256
ecdh-sha2-nistp384
ecdh-sha2-nistp521
gss-group14-sha256-toWM5Slw5Ew8Mqkay+al2g==
gss-group16-sha512-toWM5Slw5Ew8Mqkay+al2g==
gss-nistp256-sha256-toWM5Slw5Ew8Mqkay+al2g==
gss-curve25519-sha256-toWM5Slw5Ew8Mqkay+al2g==
gss-group14-sha1-toWM5Slw5Ew8Mqkay+al2g==
gss-gex-sha1-toWM5Slw5Ew8Mqkay+al2g==

The default value is: curve25519-sha256,curve25519-sha256@libssh.org,diffie-hellman-group-exchange-sha256,diffie-hellman-group14-sha256,diffie-hellman-group16-sha512,diffie-hellman-group18-sha512,ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,diffie-hellman-group1-sha1,gss-group14-sha256-toWM5Slw5Ew8Mqkay+al2g==,gss-group16-sha512-toWM5Slw5Ew8Mqkay+al2g==,gss-nistp256-sha256-toWM5Slw5Ew8Mqkay+al2g==,gss-curve25519-sha256-toWM5Slw5Ew8Mqkay+al2g==,gss-group14-sha1-toWM5Slw5Ew8Mqkay+al2g==,gss-gex-sha1-toWM5Slw5Ew8Mqkay+al2g==.

SSHKeyRenegotiate: Causes the component to renegotiate the SSH keys.

Once this setting is queried, the component will renegotiate the SSH keys with the remote host.

Example: SSHClient.Config("SSHKeyRenegotiate")

SSHMacAlgorithms: Specifies the supported Mac algorithms.

This may be used to specify an alternate list of supported Mac algorithms used during SSH negotiation. This also specifies the order in which the Mac algorithms are preferred. The value should contain a comma separated list of algorithms. Supported algorithms are:

hmac-sha1
hmac-md5
hmac-sha1-96
hmac-md5-96
hmac-sha2-256
hmac-sha2-256-96
hmac-sha2-512
hmac-sha2-512-96
hmac-ripemd160
hmac-ripemd160-96
hmac-sha2-256-etm@openssh.com
hmac-sha2-512-etm@openssh.com
umac-64@openssh.com
umac-64-etm@openssh.com
umac-128@openssh.com
umac-128-etm@openssh.com

The default value is hmac-sha2-256,hmac-sha2-512,hmac-sha1,hmac-md5,hmac-ripemd160,hmac-sha1-96,hmac-md5-96,hmac-sha2-256-96,hmac-sha2-512-96,hmac-ripemd160-96,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com,umac-64@openssh.com,umac-64-etm@openssh.com,umac-128@openssh.com,umac-128-etm@openssh.com.

SSHPubKeyAuthSigAlgorithms: Specifies the enabled signature algorithms that may be used when attempting public key authentication.

This setting specifies a list of signature algorithms that may be used when authenticating to the server using public key authentication. This applies only when public key authentication is performed by the client.

The setting should be a comma separated list of algorithms. At runtime the class will evaluate the specified algorithms and if the algorithm is applicable to the certificate specified in SSHCert it will be used. If the algorithm is not applicable the class will evaluate the next algorithm. Possible values are:

ssh-rsa
rsa-sha2-256
rsa-sha2-512
ssh-dss
ecdsa-sha2-nistp256
ecdsa-sha2-nistp384
ecdsa-sha2-nistp521
ssh-ed25519
x509v3-sign-rsa
x509v3-sign-dss

The default value in Windows is ssh-rsa,rsa-sha2-256,rsa-sha2-512,ssh-dss,ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,ssh-ed25519.

rsa-sha2-256 and rsa-sha2-512 notes

The class will query the server for supported algorithms when connecting. If the server indicates support for rsa-sha2-256 or rsa-sha2-512 and the algorithm is present in the list defined by this setting (as in the default value), that algorithm will be used instead of ssh-rsa even when ssh-rsa appears first in the list.

For the rsa-sha2-256 and rsa-sha2-512 algorithms to be automatically preferred the server must support the ext-info-c mechanism. In practice, older servers do not support this and in that case ssh-rsa will be used since it appears first in the list. Newer servers do support this mechanism and in that case rsa-sha2-256 or rsa-sha2-512 will be used even though it appears after ssh-rsa.

This behavior has been carefully designed to provide maximum compatibility while automatically using more secure algorithms when connecting to servers which support them.

SSHPublicKeyAlgorithms: Specifies the supported public key algorithms for the server's public key.

This setting specifies the allowed public key algorithms for the server's public key. This list controls only the public key algorithm used when authenticating the server's public key. This list has no bearing on the public key algorithms that can be used by the client when performing public key authentication to the server. The default value is ssh-ed25519,ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,rsa-sha2-256,rsa-sha2-512,ssh-rsa,ssh-dss,x509v3-sign-rsa,x509v3-sign-dss.

SSHVersionPattern: The pattern used to match the remote host's version string.

This configuration setting specifies the pattern used to accept or deny the remote host's SSH version string. It takes a comma-delimited list of patterns to match. The default value is "*SSH-1.99-*,*SSH-2.0-*" and will accept connections from SSH 1.99 and 2.0 hosts. As an example, the below value would accept connections for SSH 1.99, 2.0, and 2.99 hosts.

*SSH-1.99-*,*SSH-2.0-*,*SSH-2.99-*

TryAllAvailableAuthMethods: If set to true, the class will try all available authentication methods.

The default value is false. When set to true, the class will try to authenticate using all methods that it has credentials for and the server supports.

UseStrictKeyExchange: Specifies how strict key exchange is supported.

This setting controls whether strict key exchange (strict kex) is enabled to mitigate the Terrapin attack. When enabled, the class will indicate support for strict key exchange by automatically including the pseudo-algorithm kex-strict-c-v00@openssh.com for client classes and kex-strict-s-v00@openssh.com for server classes in the list of supported key exchange algorithms.

Since both client and server must implement strict key exchange to effectively mitigate the Terrapin attack, the class provides options to further control the behavior in different scenarios. Possible values for this setting are:


`0`	Disabled. Strict key exchange is not supported in the class.
`1` (default)	Enabled, but not enforced. This setting enables strict key exchange, but if the remote host does not support strict key exchange the connection is still allowed to continue.
`2`	Enabled, but reject affected algorithms if the remote host does not support strict key exchange. If the remote host supports strict key exchange all algorithms may be used. If the remote host does not support strict key exchange the connection will only continue if the selected encryption and MAC algorithms are not affected by the Terrapin attack.
`3`	Required. If the remote host does not support strict key exchange the connection will fail.

WaitForChannelClose: Whether to wait for channels to be closed before disconnected.

This setting controls whether the class will wait for a server response to the SSH_MSG_CHANNEL_CLOSE when disconnecting. When the class disconnects it will first attempt to close all open channels by sending a SSH_MSG_CHANNEL_CLOSE for each channel. This setting controls whether the class will wait for a server response after sending the messages.

When True (default) the class will wait for a response to the channel close message until the responses have been received, the server closes the connection, or Timeout seconds is reached.

When False the class will still send the channel close messages but will not wait for a response and will proceed to close the connection.

WaitForServerDisconnect: Whether to wait for the server to close the connection.

This setting controls whether to wait for the server to close the connection when SSHLogoff is called.

When set to True the class will initiate the disconnection sequence by sending SSH_MSG_DISCONNECT but will not close the connection, and instead will wait for the server to close the connection. Setting this to True may be beneficial in circumstances where many connections are being established, to avoid port exhaustion when sockets are in a TIME_WAIT state. Allowing the server to close the connection avoids the TIME_WAIT state of socket on the client machine.

When set to False (default) the client will close the connection. It is recommended to use this value unless there is a specific need to change it.

TCPClient Config Settings

CloseStreamAfterTransfer: If true, the component will close the upload or download stream after the transfer.

This setting determines whether the input or output stream is closed after the transfer completes. When set to True (default), all streams will be closed after a transfer is completed. In order to keep streams open after the transfer of data, set this to False. the default value is True.

ConnectionTimeout: Sets a separate timeout value for establishing a connection.

When set, this configuration setting allows you to specify a different timeout value for establishing a connection. Otherwise, the class will use Timeout for establishing a connection and transmitting/receiving data.

FirewallAutoDetect: Tells the class whether or not to automatically detect and use firewall system settings, if available.

This configuration setting is provided for use by classs that do not directly expose Firewall properties.

FirewallHost: Name or IP address of firewall (optional).

If a FirewallHost is given, requested connections will be authenticated through the specified firewall when connecting.

If the FirewallHost setting is set to a Domain Name, a DNS request is initiated. Upon successful termination of the request, the FirewallHost setting is set to the corresponding address. If the search is not successful, an error is returned.

Note: This setting is provided for use by classs that do not directly expose Firewall properties.

FirewallListener: If true, the component binds to a SOCKS firewall as a server (TCPClient only).

This entry is for TCPClient only and does not work for other components that descend from TCPClient.

If this entry is set, the class acts as a server. RemoteHost and RemotePort are used to tell the SOCKS firewall in which address and port to listen to. The firewall rules may ignore RemoteHost, and it is recommended that RemoteHost be set to empty string in this case.

RemotePort is the port in which the firewall will listen to. If set to 0, the firewall will select a random port. The binding (address and port) is provided through the ConnectionStatus event.

The connection to the firewall is made by calling the Connect method.

FirewallPassword: Password to be used if authentication is to be used when connecting through the firewall.

If FirewallHost is specified, the FirewallUser and FirewallPassword settings are used to connect and authenticate to the given firewall. If the authentication fails, the class throws an exception.

Note: This setting is provided for use by classs that do not directly expose Firewall properties.

FirewallPort: The TCP port for the FirewallHost;.

The FirewallPort is set automatically when FirewallType is set to a valid value.

Note: This configuration setting is provided for use by classs that do not directly expose Firewall properties.

FirewallType: Determines the type of firewall to connect through.

The appropriate values are as follows:


0	No firewall (default setting).
1	Connect through a tunneling proxy. FirewallPort is set to 80.
2	Connect through a SOCKS4 Proxy. FirewallPort is set to 1080.
3	Connect through a SOCKS5 Proxy. FirewallPort is set to 1080.
10	Connect through a SOCKS4A Proxy. FirewallPort is set to 1080.

Note: This setting is provided for use by classs that do not directly expose Firewall properties.

FirewallUser: A user name if authentication is to be used connecting through a firewall.

If the FirewallHost is specified, the FirewallUser and FirewallPassword settings are used to connect and authenticate to the Firewall. If the authentication fails, the class throws an exception.

Note: This setting is provided for use by classs that do not directly expose Firewall properties.

KeepAliveInterval: The retry interval, in milliseconds, to be used when a TCP keep-alive packet is sent and no response is received.

When set, TCPKeepAlive will automatically be set to True. A TCP keep-alive packet will be sent after a period of inactivity as defined by KeepAliveTime. If no acknowledgment is received from the remote host, the keep-alive packet will be sent again. This configuration setting specifies the interval at which the successive keep-alive packets are sent in milliseconds. This system default if this value is not specified here is 1 second.

Note: This value is not applicable in macOS.

KeepAliveTime: The inactivity time in milliseconds before a TCP keep-alive packet is sent.

When set, TCPKeepAlive will automatically be set to True. By default, the operating system will determine the time a connection is idle before a Transmission Control Protocol (TCP) keep-alive packet is sent. This system default if this value is not specified here is 2 hours. In many cases, a shorter interval is more useful. Set this value to the desired interval in milliseconds.

Linger: When set to True, connections are terminated gracefully.

This property controls how a connection is closed. The default is True.

In the case that Linger is True (default), two scenarios determine how long the connection will linger. In the first, if LingerTime is 0 (default), the system will attempt to send pending data for a connection until the default IP timeout expires.

In the second scenario, if LingerTime is a positive value, the system will attempt to send pending data until the specified LingerTime is reached. If this attempt fails, then the system will reset the connection.

The default behavior (which is also the default mode for stream sockets) might result in a long delay in closing the connection. Although the class returns control immediately, the system could hold system resources until all pending data are sent (even after your application closes).

Setting this property to False forces an immediate disconnection. If you know that the other side has received all the data you sent (e.g., by a client acknowledgment), setting this property to False might be the appropriate course of action.

LingerTime: Time in seconds to have the connection linger.

LingerTime is the time, in seconds, the socket connection will linger. This value is 0 by default, which means it will use the default IP timeout.

LocalHost: The name of the local host through which connections are initiated or accepted.

The LocalHost setting contains the name of the local host as obtained by the gethostname() system call, or if the user has assigned an IP address, the value of that address.

If the class is connected, the LocalHost setting shows the IP address of the interface through which the connection is made in internet dotted format (aaa.bbb.ccc.ddd). In most cases, this is the address of the local host, except for multi-homed hosts (machines with more than one IP interface).

LocalPort: The port in the local host where the class binds.

This must be set before a connection is attempted. It instructs the class to bind to a specific port (or communication endpoint) in the local machine.

Setting this to 0 (default) enables the system to choose a port at random. The chosen port will be shown by LocalPort after the connection is established.

LocalPort cannot be changed once a connection is made. Any attempt to set this when a connection is active will generate an error.

This; setting is useful when trying to connect to services that require a trusted port in the client side. An example is the remote shell (rsh) service in UNIX systems.

MaxLineLength: The maximum amount of data to accumulate when no EOL is found.

MaxLineLength is the size of an internal buffer, which holds received data while waiting for an EOL string.

If an EOL string is found in the input stream before MaxLineLength bytes are received, the DataIn event is fired with the EOL parameter set to True, and the buffer is reset.

If no EOL is found, and MaxLineLength bytes are accumulated in the buffer, the DataIn event is fired with the EOL parameter set to False, and the buffer is reset.

The minimum value for MaxLineLength is 256 bytes. The default value is 2048 bytes.

MaxTransferRate: The transfer rate limit in bytes per second.

This configuration setting can be used to throttle outbound TCP traffic. Set this to the number of bytes to be sent per second. By default, this is not set and there is no limit.

ProxyExceptionsList: A semicolon separated list of hosts and IPs to bypass when using a proxy.

This configuration setting optionally specifies a semicolon-separated list of hostnames or IP addresses to bypass when a proxy is in use. When requests are made to hosts specified in this property, the proxy will not be used. For instance:

www.google.com;www.nsoftware.com

TCPKeepAlive: Determines whether or not the keep alive socket option is enabled.

If set to True, the socket's keep-alive option is enabled and keep-alive packets will be sent periodically to maintain the connection. Set KeepAliveTime and KeepAliveInterval to configure the timing of the keep-alive packets.

Note: This value is not applicable in Java.

TcpNoDelay: Whether or not to delay when sending packets.

When true, the socket will send all data that is ready to send at once. When false, the socket will send smaller buffered packets of data at small intervals. This is known as the Nagle algorithm.

By default, this config is set to false.

UseIPv6: Whether to use IPv6.

When set to 0 (default), the class will use IPv4 exclusively. When set to 1, the class will use IPv6 exclusively. To instruct the class to prefer IPv6 addresses, but use IPv4 if IPv6 is not supported on the system, this setting should be set to 2. The default value is 0. Possible values are:


0	IPv4 Only
1	IPv6 Only
2	IPv6 with IPv4 fallback

UseNTLMv2: Whether to use NTLM V2.

When authenticating with NTLM, this setting specifies whether NTLM V2 is used. By default this value is False and NTLM V1 will be used. Set this to True to use NTLM V2.

Socket Config Settings

AbsoluteTimeout: Determines whether timeouts are inactivity timeouts or absolute timeouts.

If AbsoluteTimeout is set to True, any method which does not complete within Timeout seconds will be aborted. By default, AbsoluteTimeout is False, and the timeout is an inactivity timeout.

Note: This option is not valid for UDP ports.

FirewallData: Used to send extra data to the firewall.

When the firewall is a tunneling proxy, use this property to send custom (additional) headers to the firewall (e.g. headers for custom authentication schemes).

InBufferSize: The size in bytes of the incoming queue of the socket.

This is the size of an internal queue in the TCP/IP stack. You can increase or decrease its size depending on the amount of data that you will be receiving. Increasing the value of the InBufferSize setting can provide significant improvements in performance in some cases.

Some TCP/IP implementations do not support variable buffer sizes. If that is the case, when the class is activated the InBufferSize reverts to its defined size. The same happens if you attempt to make it too large or too small.

OutBufferSize: The size in bytes of the outgoing queue of the socket.

This is the size of an internal queue in the TCP/IP stack. You can increase or decrease its size depending on the amount of data that you will be sending. Increasing the value of the OutBufferSize setting can provide significant improvements in performance in some cases.

Some TCP/IP implementations do not support variable buffer sizes. If that is the case, when the class is activated the OutBufferSize reverts to its defined size. The same happens if you attempt to make it too large or too small.

TCPServer Config Settings

AllowedClients: A comma-separated list of host names or IP addresses that can access the class.

This configuration setting defines a comma-separated list of host names or IPv4 addresses that may access the class. The wildcard character "*" is supported. The default value is "*" and all connections are accepted.

When a client connects, the client's address is checked against the list defined here. If there is no match, the ConnectionRequest event fires with an Accept value set to False. If no action is taken within the ConnectionRequest event, the client will be disconnected.

BindExclusively: Whether or not the component considers a local port reserved for exclusive use.

If this is True (default), the component will bind to the local port with the ExclusiveAddressUse option set, meaning that nothing else can bind to the same port. Also the component will not be able to bind to local ports that are already in use by some other instance, and attempts to do so will result in failure.

BlockedClients: A comma-separated list of host names or IP addresses that cannot access the class.

This configuration setting defines a comma-separated list of host names or IPv4 addresses that cannot access the class.The default value is "" and all connections are accepted.

When a client connects, the client's address is checked against the list defined here. If there is a match, the ConnectionRequest event fires with an Accept value set to False. If no action is taken within the ConnectionRequest event, the client will not be connected.

CloseStreamAfterTransfer: If true, the component will close the upload or download stream after the transfer.

DefaultConnectionTimeout: The inactivity timeout applied to the SSL handshake.

This configuration setting specifies the inactivity (in seconds) to apply to incoming Secure Sockets Layer (SSL) connections. When set to a positive value, if the other end is unresponsive for the specified number of seconds, the connection will timeout. This is not applicable to the entire handshake. It is applicable only to the inactivity of the connecting client during the handshake if a response is expected and none is received within the timeout window. The default value is 0, and no connection-specific timeout is applied.

Note: This is applicable only to incoming SSL connections. This should be set only if there is a specific reason to do so.

InBufferSize: The size in bytes of the incoming queue of the socket.

This is the size of an internal queue in the Transmission Control Protocol (TCP)/IP stack. You can increase or decrease its size depending on the amount of data that you will be receiving. Increasing the value of the InBufferSize setting can provide significant improvements in performance in some cases.

Some TCP/IP implementations do not support variable buffer sizes. If that is the case, when the class is activated, the InBufferSize reverts to its defined size. The same thing will happen if you attempt to make it too large or too small.

InBufferSize is shared among incoming connections. When the property is set, the corresponding value is set for incoming connections as they are accepted. Existing connections are not modified.

KeepAliveInterval: The retry interval, in milliseconds, to be used when a TCP keep-alive packet is sent and no response is received.

A TCP keep-alive packet will be sent after a period of inactivity, as defined by KeepAliveTime. If no acknowledgment is received from the remote host, the keep-alive packet will be sent again. This setting specifies the interval at which the successive keep-alive packets are sent in milliseconds. If this value is not specified here, the system default is 1 second. This setting is applicable to all connections.

Note: This value is not applicable in macOS.

KeepAliveTime: The inactivity time in milliseconds before a TCP keep-alive packet is sent.

By default, the operating system will determine the time a connection is idle before a TCP keep-alive packet is sent. If this value is not specified here, the system default is 2 hours. In many cases, a shorter interval is more useful. Set this value to the desired interval in milliseconds. This setting is applicable to all connections.

MaxConnections: The maximum number of connections available.

This is the maximum number of connections available. This property must be set before Listening is set to True, and once set, it can no longer be changed for the current instance of the class. The maximum value for this setting is 100,000 connections. Use this setting with caution. Extremely large values may affect performance.

OutBufferSize: The size in bytes of the outgoing queue of the socket.

This is the size of an internal queue in the TCP/IP stack. You can increase or decrease its size depending on the amount of data that you will be sending. Increasing the value of the OutBufferSize setting can provide significant improvements in performance in some cases.

Some TCP/IP implementations do not support variable buffer sizes. If that is the case, when the class is activated the OutBufferSize reverts to its defined size. The same thing will happen if you attempt to make it too large or too small.

OutBufferSize is shared among incoming connections. When the property is set, the corresponding value is set for incoming connections as they are accepted. Existing connections are not modified.

PreferredDHGroupBits: Size of the Diffie-Hellman group, in bits.

This configuration setting specifies the key length used by the Diffe-Hellman key algorithm. The default value is 2048 (bits).

TcpNoDelay: Whether or not to delay when sending packets.

When true, the socket will send all data that is ready to send at once. When false, the socket will send smaller buffered packets of data at small intervals. This is known as the Nagle algorithm.

By default, this config is set to false.

UseIPv6: Whether to use IPv6.

When set to 0 (default), the class will use IPv4 exclusively. When set to 1, the class will use IPv6 exclusively. When set to 2, the class will listen for both IPv4 and IPv6 connections. If IPv6 is not available on the system, only IPv4 will be used. The default value is 0. Possible values are as follows:


0	IPv4 Only
1	IPv6 Only
2	IPv6 and IPv4

Base Config Settings

BuildInfo: Information about the product's build.

When queried, this setting will return a string containing information about the product's build.

GUIAvailable: Whether or not a message loop is available for processing events.

In a GUI-based application, long-running blocking operations may cause the application to stop responding to input until the operation returns. The class will attempt to discover whether or not the application has a message loop and, if one is discovered, it will process events in that message loop during any such blocking operation.

In some non-GUI applications, an invalid message loop may be discovered that will result in errant behavior. In these cases, setting GUIAvailable to false will ensure that the class does not attempt to process external events.

LicenseInfo: Information about the current license.

When queried, this setting will return a string containing information about the license this instance of a class is using. It will return the following information:

Product: The product the license is for.
Product Key: The key the license was generated from.
License Source: Where the license was found (e.g., RuntimeLicense, License File).
License Type: The type of license installed (e.g., Royalty Free, Single Server).
Last Valid Build: The last valid build number for which the license will work.

MaskSensitive: Whether sensitive data is masked in log messages.

In certain circumstances it may be beneficial to mask sensitive data, like passwords, in log messages. Set this to true to mask sensitive data. The default is true.

This setting only works on these classes: AS3Receiver, AS3Sender, Atom, Client(3DS), FTP, FTPServer, IMAP, OFTPClient, SSHClient, SCP, Server(3DS), Sexec, SFTP, SFTPServer, SSHServer, TCPClient, TCPServer.

UseDaemonThreads: Whether threads created by the class are daemon threads.

If set to True (default), when the class creates a thread, the thread's Daemon property will be explicitly set to True. When set to False, the class will not set the Daemon property on the created thread. The default value is True.

UseFIPSCompliantAPI: Tells the class whether or not to use FIPS certified APIs.

When set to true, the class will utilize the underlying operating system's certified APIs. Java editions, regardless of OS, utilize Bouncy Castle FIPS, while all the other Windows editions make use of Microsoft security libraries.

The Java edition requires installation of the FIPS certified Bouncy Castle library regardless of the target operating system. This can be downloaded from https://www.bouncycastle.org/fips-java/. Only the "Provider" library is needed. The jar file should then be installed in a JRE search path.

In the application where the component will be used the following classes must be imported:

import java.security.Security; import org.bouncycastle.jcajce.provider.BouncyCastleFipsProvider;

The Bouncy Castle provider must be added as a valid provider and must also be configured to operate in FIPS mode:

System.setProperty("org.bouncycastle.fips.approved_only","true"); Security.addProvider(new BouncyCastleFipsProvider());

When UseFIPSCompliantAPI is true, SSL enabled classes can optionally be configured to use the TLS Bouncy Castle library. When SSLProvider is set to sslpAutomatic (default) or sslpInternal an internal TLS implementation is used, but all cryptographic operations are offloaded to the BCFIPS provider in order to achieve FIPS compliant operation. If SSLProvider is set to sslpPlatform the Bouncy Castle JSSE will be used in place of the internal TLS implementation.

To enable the use of the Bouncy Castle JSSE take the following steps in addition to the steps above. Both the Bouncy Castle FIPS provider and the Bouncy Castle JSSE must be configured to use the Bouncy Castle TLS library in FIPS mode. Obtain the Bouncy Castle TLS library from https://www.bouncycastle.org/fips-java/. The jar file should then be installed in a JRE search path.

In the application where the component will be used the following classes must be imported:

import java.security.Security; import org.bouncycastle.jcajce.provider.BouncyCastleFipsProvider; //required to use BCJSSE when SSLProvider is set to sslpPlatform import org.bouncycastle.jsse.provider.BouncyCastleJsseProvider;

The Bouncy Castle provider must be added as a valid provider and must also be configured to operate in FIPS mode:

System.setProperty("org.bouncycastle.fips.approved_only","true"); Security.addProvider(new BouncyCastleFipsProvider()); //required to use BCJSSE when SSLProvider is set to sslpPlatform Security.addProvider(new BouncyCastleJsseProvider("fips:BCFIPS")); //optional - configure logging level of BCJSSE Logger.getLogger("org.bouncycastle.jsse").setLevel(java.util.logging.Level.OFF); //configure the class to use BCJSSE component.setSSLProvider(1); //platform component.config("UseFIPSCompliantAPI=true"); Note: TLS 1.3 support requires the Bouncy Castle TLS library version 1.0.14 or later.

FIPS mode can be enabled by setting the UseFIPSCompliantAPI configuration setting to true. This is a static setting which applies to all instances of all classes of the toolkit within the process. It is recommended to enable or disable this setting once before the component has been used to establish a connection. Enabling FIPS while an instance of the component is active and connected may result in unexpected behavior.

For more details please see the FIPS 140-2 Compliance article.

Note: Enabling FIPS-compliance requires a special license; please contact sales@nsoftware.com for details.

UseInternalSecurityAPI: Whether or not to use the system security libraries or an internal implementation.

When set to false, the class will use the system security libraries by default to perform cryptographic functions where applicable.

Setting this configuration setting to true tells the class to use the internal implementation instead of using the system security libraries.

This setting is set to false by default on all platforms.

Trappable Errors (Sshtunnel Class)

SSHTunnel Errors


	100 You cannot change the RemotePort at this time. A connection is in progress.
	101 You cannot change the RemoteHost at this time. A connection is in progress.
	102 The RemoteHost address is invalid (0.0.0.0).
	104 TCPServer is already listening.
	106 Cannot change LocalPort when TCPServer is Listening.
	107 Cannot change LocalHost when TCPServer is Listening.
	108 Cannot change MaxConnections when TCPServer is Listening.
	112 You cannot change MaxLineLength at this time. A connection is in progress.
	116 RemotePort cannot be zero. Please specify a valid service port number.
	126 Invalid `ConnectionId`.
	1201 Could not forward connection. A detailed message follows.
	1202 Could not forward connection/channel data. A detailed message follows.

SSHClient Errors


	1001 Server has disconnected.
	1002 Protocol version unsupported or other issue with version string.
	1003 Cannot negotiate algorithms.
	1005 Selected algorithm unsupported.
	1006 Cannot set keys.
	1010 Unexpected algorithm.
	1011 Cannot create exchange hash.
	1012 Cannot make key.
	1013 Cannot sign data.
	1014 Cannot encrypt packet.
	1015 Cannot decrypt packet.
	1016 Cannot decompress packet.
	1020 Failure to open channel.
	1021 Invalid channel ID.
	1022 Invalid channel data.
	1023 Invalid channel message.
	1024 SSH message unimplemented.
	1027 Server message unsupported.
	1030 Server's host key was rejected. The host key may be accepted within the SSHServerAuthentication event or using the SSHAcceptServerHostKey property.
	1031 Cannot verify server's host key.
	1032 Authentication failed. Check description for details.
	1033 Channel request failed.
	1034 Diffie-Hellman exchange failed.
	1036 SSH connection failed.
	1037 SSH reconnect limit reached.
	1038 Elliptic Curve Diffie-Hellman exchange failed.
	1039 SSH keep-alive limit reached.
	1098 Request failure.
	1130 Would block error.
	1133 Would block, reason: key reExchange.

TCPClient Errors


	100 You cannot change the RemotePort at this time. A connection is in progress.
	101 You cannot change the RemoteHost (Server) at this time. A connection is in progress.
	102 The RemoteHost address is invalid (0.0.0.0).
	104 Already connected. If you want to reconnect, close the current connection first.
	106 You cannot change the LocalPort at this time. A connection is in progress.
	107 You cannot change the LocalHost at this time. A connection is in progress.
	112 You cannot change MaxLineLength at this time. A connection is in progress.
	116 RemotePort cannot be zero. Please specify a valid service port number.
	117 You cannot change the UseConnection option while the class is active.
	135 Operation would block.
	201 Timeout.
	211 Action impossible in control's present state.
	212 Action impossible while not connected.
	213 Action impossible while listening.
	301 Timeout.
	303 Could not open file.
	434 Unable to convert string to selected CodePage.
	1105 Already connecting. If you want to reconnect, close the current connection first.
	1117 You need to connect first.
	1119 You cannot change the LocalHost at this time. A connection is in progress.
	1120 Connection dropped by remote host.

TCP/IP Errors


	10004 [10004] Interrupted system call.
	10009 [10009] Bad file number.
	10013 [10013] Access denied.
	10014 [10014] Bad address.
	10022 [10022] Invalid argument.
	10024 [10024] Too many open files.
	10035 [10035] Operation would block.
	10036 [10036] Operation now in progress.
	10037 [10037] Operation already in progress.
	10038 [10038] Socket operation on non-socket.
	10039 [10039] Destination address required.
	10040 [10040] Message too long.
	10041 [10041] Protocol wrong type for socket.
	10042 [10042] Bad protocol option.
	10043 [10043] Protocol not supported.
	10044 [10044] Socket type not supported.
	10045 [10045] Operation not supported on socket.
	10046 [10046] Protocol family not supported.
	10047 [10047] Address family not supported by protocol family.
	10048 [10048] Address already in use.
	10049 [10049] Can't assign requested address.
	10050 [10050] Network is down.
	10051 [10051] Network is unreachable.
	10052 [10052] Net dropped connection or reset.
	10053 [10053] Software caused connection abort.
	10054 [10054] Connection reset by peer.
	10055 [10055] No buffer space available.
	10056 [10056] Socket is already connected.
	10057 [10057] Socket is not connected.
	10058 [10058] Can't send after socket shutdown.
	10059 [10059] Too many references, can't splice.
	10060 [10060] Connection timed out.
	10061 [10061] Connection refused.
	10062 [10062] Too many levels of symbolic links.
	10063 [10063] File name too long.
	10064 [10064] Host is down.
	10065 [10065] No route to host.
	10066 [10066] Directory not empty
	10067 [10067] Too many processes.
	10068 [10068] Too many users.
	10069 [10069] Disc Quota Exceeded.
	10070 [10070] Stale NFS file handle.
	10071 [10071] Too many levels of remote in path.
	10091 [10091] Network subsystem is unavailable.
	10092 [10092] WINSOCK DLL Version out of range.
	10093 [10093] Winsock not loaded yet.
	11001 [11001] Host not found.
	11002 [11002] Non-authoritative 'Host not found' (try again or check DNS setup).
	11003 [11003] Non-recoverable errors: FORMERR, REFUSED, NOTIMP.
	11004 [11004] Valid name, no data record (check DNS setup).