SSHClient Class

Properties Methods Events Config Settings Errors

The SSHClient class implements a fully functional, open-ended Secure Shell (SSH) client.

Syntax

ipworksssh.SSHClient

Remarks

The SSHClient class can be used to perform any number of tasks secured by the Secure Shell (SSH) protocol. First set SSHHost, SSHUser and either SSHPassword or SSHCert , then call SSHLogon to establish a secure connection.

To open channels, use OpenChannel. To open a channel to tunnel data to a remote machine, call OpenTcpIpChannel. The Channels property contains a list of all of the channels open for the current instance of the class.

Once a "session" channel has been opened, you can call StartService to initialize a service on that channel. If you are using a "shell" service, you can call OpenTerminal to establish a pseudo-terminal for formatting the data output from the shell.

Data received from the server will be fired through SSHChannelData events. Any requests received can be processed through the SSHChannelRequest event.

Property List

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


Channels	The collection of currently open channels.
Connected	Whether the class is connected.
Firewall	A set of properties related to firewall access.
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 with the class when calling SSHLogon .
SSHCert	A certificate to be used for authenticating the SSHUser .
SSHCompressionAlgorithms	The comma-separated list containing all allowable compression algorithms.
SSHEncryptionAlgorithms	The comma-separated list containing all allowable encryption algorithms.
SSHHost	The address of the Secure Shell (SSH) host.
SSHKeyExchangeAlgorithms	The comma-separated list containing all allowable key exchange algorithms.
SSHMacAlgorithms	The comma-separated list containing all allowable message authentication algorithms.
SSHPassword	The password for Secure Shell (SSH) password-based authentication.
SSHPort	The port on the Secure Shell (SSH) server where the SSH service is running; by default, 22.
SSHPublicKeyAlgorithms	The comma-separated list containing all allowable public key algorithms for the Secure Shell (SSH) server's public key.
SSHUser	The username for Secure Shell (SSH) authentication.
Timeout	This property includes the timeout for the class.

Method List

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


ChangeRecordLength	Changes the length of received data records.
CloseChannel	Closes a existing SSHChannel .
Config	Sets or retrieves a configuration setting.
Connect	Connects to the Secure Shell (SSH) host without logging in.
DecodePacket	Decodes a hex-encoded Secure Shell (SSH) packet.
Disconnect	Disconnects from the server without first logging off.
DoEvents	This method processes events from the internal message queue.
EncodePacket	Hex encodes a Secure Shell (SSH) packet.
ExchangeKeys	Causes the class to exchange a new set of session keys with the SSHHost .
GetSSHParam	Reads a field from a Secure Shell (SSH) packet's payload.
GetSSHParamBytes	Reads a field from a Secure Shell (SSH) packet's payload.
OpenChannel	Opens a new SSHChannel .
OpenTcpIpChannel	Opens a special Transmission Control Protocol (TCP)/IP tunneling SSHChannel .
OpenTerminal	Creates a pseudo-terminal to be used to help display data for a channel.
Reset	This method will reset the class.
SendBytes	Sends binary data to the specified channel.
SendChannelData	Sends data over a Secure Shell (SSH) channel.
SendSSHPacket	Sends an encoded Secure Shell (SSH) packet to the server.
SendText	Sends text to the specified channel.
SetSSHParam	Writes a field to the end of a payload.
SSHLogoff	Logs off from the Secure Shell (SSH) server.
SSHLogon	Logs on to the SSHHost using the current SSHUser and SSHPassword .
StartService	Requests the given service on a target channel.

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	Fired immediately after a connection completes (or fails).
ConnectionStatus	Fired to indicate changes in the connection state.
Disconnected	Fired when a connection is closed.
Error	Fired when information is available about errors during data delivery.
Log	Fired once for each log message.
SSHChannelClosed	Fired when a channel is closed.
SSHChannelData	Fired when the SSHHost sends channel data to the client.
SSHChannelEOF	Fired when the remote peer signals the end of the data stream for the channel.
SSHChannelOpened	Fired when a channel is successfully opened.
SSHChannelOpenRequest	Fired when a host attempts to open a new channel.
SSHChannelReadyToSend	Fired when the class is ready to send data.
SSHChannelRequest	Fired when the SSHHost sends a channel request to the client.
SSHChannelRequested	Fired if the SSHChannelRequest was successful; any further processing for the channel request should be done here.
SSHCustomAuth	Fired when the class is doing a 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	Fired to track 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.


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.
DoNotRepeatAuthMethods	Whether the class will repeat authentication methods during multifactor authentication.
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.
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.
MaskSensitiveData	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.

Channels Property (SSHClient Class)

The collection of currently open channels.

Syntax

public SSHChannelMap getChannels();

Remarks

The Secure Shell (SSH) 2.0 specification allows for multiple channels to be opened over a single Transmission Control Protocol (TCP)/IP connection. The Channels property represents the channels that are currently open. A new SSHChannel can be opened with OpenChannel, and data can be sent over it with SendChannelData.

This collection is a hashtable where the channel's Id string is used as the key to the desired Secure Shell (SSH) channel object.

This property is read-only.

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

Connected Property (SSHClient Class)

Whether the class is connected.

Syntax

public boolean isConnected();

Default Value

False

Remarks

This property is used to determine whether or not the class is connected to the remote host. Use the Connect and Disconnect methods to manage the connection.

This property is read-only and not available at design time.

Firewall Property (SSHClient 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.

LocalHost Property (SSHClient 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

This 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 multihomed hosts (machines with more than one IP interface) setting LocalHost to the IP address of an interface will make the class initiate connections (or accept in the case of server classs) only through that interface. It is recommended to provide an IP address rather than a hostname when setting this property to ensure the desired interface is used.

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 multihomed 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 (SSHClient 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 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 on the client side.

SSHAcceptServerHostKey Property (SSHClient 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 (SSHClient Class)

The authentication method to be used with 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 amGSSAPIKeyex = 6;
  public final static int amCustom = 99;

Default Value

Remarks

The Secure Shell (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 as anonymous.
`amMultiFactor` (1)	This allows the class to attempt a multistep 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.
`amGSSAPIKeyex` (6)	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.
`amCustom` (99)	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.

Example 1. User/Password Authentication: Control.SSHAuthMode = SftpSSHAuthModes.amPassword Control.SSHUser = "username" Control.SSHPassword = "password" Control.SSHLogon("server", 22) Example 2. Public Key Authentication: Control.SSHAuthMode = SftpSSHAuthModes.amPublicKey Control.SSHUser = "username" Control.SSHCert = New Certificate(CertStoreTypes.cstPFXFile, "cert.pfx", "certpassword", "*") Control.SSHLogon("server", 22)

SSHCert Property (SSHClient Class)

A certificate to be used for authenticating the SSHUser .

Syntax

public Certificate getSSHCert();
public void setSSHCert(Certificate SSHCert);

Remarks

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 it will attempt to use those values to verify the signature.

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

SSHCompressionAlgorithms Property (SSHClient Class)

The comma-separated list containing all allowable compression algorithms.

Syntax

public String getSSHCompressionAlgorithms();
public void setSSHCompressionAlgorithms(String SSHCompressionAlgorithms);

Default Value

"none,zlib"

Remarks

During the Secure Shell (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. Therefore, it is important to list multiple algorithms in preferential order. If no algorithm can be agreed on, 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 (SSHClient Class)

The 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,3des-ctr,arcfour256,arcfour128,arcfour,aes256-gcm@openssh.com,aes128-gcm@openssh.com,chacha20-poly1305@openssh.com"

Remarks

During the Secure Shell (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. Therefore, it is important to list multiple algorithms in preferential order. If no algorithm can be agreed on, 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.

SSHHost Property (SSHClient Class)

The address of the Secure Shell (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.

SSHKeyExchangeAlgorithms Property (SSHClient Class)

The comma-separated list containing all allowable key exchange algorithms.

Syntax

public String getSSHKeyExchangeAlgorithms();
public void setSSHKeyExchangeAlgorithms(String SSHKeyExchangeAlgorithms);

Default Value

"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=="

Remarks

Secure Shell (SSH) allows different algorithms to be negotiated for use when establishing the security layer of the connection. This property controls the key-exchange algorithm list supplied by the class to the SSHHost. It is a comma-separated list containing the names of key-exchange algorithms as defined by section 6.5 of the SSH Transport Layer specification (RFC 4253). The key-exchange algorithms specified in RFC 4419 and RFC 8732 are also supported.

The value of this property must be a comma-separated list containing one or more of the following values:

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==

SSHMacAlgorithms Property (SSHClient Class)

The comma-separated list containing all allowable message authentication algorithms.

Syntax

public String getSSHMacAlgorithms();
public void setSSHMacAlgorithms(String SSHMacAlgorithms);

Default Value

"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,hmac-sha2-256-96-etm@openssh.com,hmac-sha2-512-96-etm@openssh.com,umac-64@openssh.com,umac-64-etm@openssh.com,umac-128@openssh.com,umac-128-etm@openssh.com"

Remarks

Secure Shell (SSH) allows different algorithms to be negotiated for use when establishing the security layer of the connection. SSHMacAlgorithms controls the message authentication code (MAC) algorithm list supplied by the class to the SSHHost. It is a comma-separated list containing the names of message authentication code (MAC) algorithms as defined by section 6.4 of the SSH Transport Layer specification (RFC 4253).

The value of this property must be a comma-separated list containing one or more of the following values:

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

SSHPassword Property (SSHClient Class)

The password for Secure Shell (SSH) password-based authentication.

Syntax

public String getSSHPassword();
public void setSSHPassword(String SSHPassword);

Default Value

Remarks

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

SSHPort Property (SSHClient Class)

The port on the Secure Shell (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.

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.

SSHPublicKeyAlgorithms Property (SSHClient Class)

The comma-separated list containing all allowable public key algorithms for the Secure Shell (SSH) server's public key.

Syntax

public String getSSHPublicKeyAlgorithms();
public void setSSHPublicKeyAlgorithms(String SSHPublicKeyAlgorithms);

Default Value

"ssh-ed25519,ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,rsa-sha2-256,rsa-sha2-512,ssh-rsa,ssh-ed448,ssh-dss,x509v3-sign-rsa,x509v3-sign-dss"

Remarks

SSH allows different algorithms to be negotiated for use when establishing the security layer of the connection. SSHPublicKeyAlgorithms controls the public key algorithm list supplied by the class to the SSHHost. It is a comma-separated list containing the names of public key algorithms as defined by section 6.6 of the SSH Transport Layer specification (RFC 4253).

The value of this property must be a comma-separated list containing one or more of the following values:


ssh-dss	Raw DSS Key
ssh-rsa	Raw RSA Key
rsa-sha2-256	Raw RSA Key
rsa-sha2-512	Raw RSA Key
x509v3-sign-rsa	X509 RSA Certificate
x509v3-sign-dss	X509 DSS Certificate
ecdsa-sha2-nistp256	Raw EC Key with curve nistp256. Note: This functionality is only available in Windows.
ecdsa-sha2-nistp384	Raw EC Key with curve nistp384. Note: This functionality is only available in Windows.
ecdsa-sha2-nistp521	Raw EC Key with curve nistp521. Note: This functionality is only available in Windows.
ssh-ed25519	Ed25519 Key
ssh-ed448	Ed448 Key

Note: The algorithms listed by this property control only the allowed public key algorithms for the SSH server's public key. This is used when authenticating the SSH server's public key. In most SSH server implementations, this list has no bearing on the public key algorithms that can be used by the client when authenticating to the SSH server using public key authentication.

SSHUser Property (SSHClient Class)

The username for Secure Shell (SSH) authentication.

Syntax

public String getSSHUser();
public void setSSHUser(String SSHUser);

Default Value

Remarks

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

Timeout Property (SSHClient Class)

This property includes the timeout for the class.

Syntax

public int getTimeout();
public void setTimeout(int timeout);

Default Value

Remarks

If the Timeout property 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.

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.

Note: By default, all timeouts are inactivity timeouts, that is, the timeout period is extended by Timeout seconds when any amount of data is successfully sent or received.

The default value for the Timeout property is 60 seconds.

ChangeRecordLength Method (SSHClient Class)

Changes the length of received data records.

Syntax

public void changeRecordLength(String channelId, int recordLength);

Remarks

This method defines the length of data records to be received (in bytes) for the specified ChannelId.

If RecordLength is set to a positive value, the class will accumulate data until RecordLength bytes of data are received, and then it will fire the SSHChannelDataIn event only with data of length RecordLength. This allows data to be received as records of known length. This method can be called at any time to change the record length, including within the DataIn event.

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

CloseChannel Method (SSHClient Class)

Closes a existing SSHChannel .

Syntax

public void closeChannel(String channelId);

Remarks

ChannelId is the identifier for the Secure Shell (SSH) channel to be closed.

Config Method (SSHClient 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 (SSHClient Class)

Connects to the Secure Shell (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 SSHLogon method, which will both establish a connection and log in to the server.

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

DecodePacket Method (SSHClient Class)

Decodes a hex-encoded Secure Shell (SSH) packet.

Syntax

public byte[] decodePacket(String encodedPacket);

Remarks

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

Disconnect Method (SSHClient Class)

Disconnects from the server without first logging off.

Syntax

public void disconnect();

Remarks

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

In most cases, the SSHLogoff method should be used to log off and disconnect from the server. Call the Disconnect method in cases in which it is desirable to immediately disconnect without first logging off.

DoEvents Method (SSHClient Class)

This method 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 (SSHClient Class)

Hex encodes a Secure Shell (SSH) packet.

Syntax

public String encodePacket(byte[] packet);

Remarks

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

ExchangeKeys Method (SSHClient Class)

Causes the class to exchange a new set of session keys with the SSHHost .

Syntax

public void exchangeKeys();

Remarks

Secure Shell (SSH) key renegotiation can be initiated by either end of an established SSH connection. ExchangeKeys allows the user to start such a renegotiation with the SSHHost. During this process, SSHStatus events will fire containing updates regarding the key negotiation process.

The SSH 2.0 specification recommends that key renegotiation be done once for 2 gigabytes (GB) of data processed by the connection, or once every day. Doing so makes it more difficult to break the security of data-intensive or long-lived connections.

GetSSHParam Method (SSHClient Class)

Reads a field from a Secure Shell (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 requested.
WantsReply (`boolean`)	Whether or not the client wants a reply to the request.

The remaining fields that are available in the payload are dependent on 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 (e.g., "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 (e.g., "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 (e.g., "sftp").

xon-xoff

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.

GetSSHParamBytes Method (SSHClient Class)

Reads a field from a Secure Shell (SSH) packet's payload.

Syntax

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

Remarks

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

OpenChannel Method (SSHClient Class)

Opens a new SSHChannel .

Syntax

public String openChannel(String channelType);

Remarks

ChannelType represents the type of Secure Shell (SSH) channel to be opened. The most common type of channel is "session". To open a channel of type "direct-tcpip", use OpenTcpIpChannel.

If the call to OpenChannel succeeds, an SSHChannel will be created and added to the Channels collection.

OpenTcpIpChannel Method (SSHClient Class)

Opens a special Transmission Control Protocol (TCP)/IP tunneling SSHChannel .

Syntax

public String openTcpIpChannel(String destHost, int destPort, String srcHost, int srcPort);

Remarks

OpenTcpIpChannel opens a special SSHChannel of type "direct-tcpip". Unlike channels opened by OpenChannel, "direct-tcpip" channels are secured data tunnels that forward data through the SSHHost to another destination.

DestHost and DestPort represent, respectively, the host name or IP address and the port for which the data of this channel are bound. When OpenTcpIpChannel is called, the SSHHost will attempt to connect to the machine identified by these parameters.

Likewise, SrcHost and SrcPort identify the originator of the data. These may be different from LocalHost and LocalPort if the current instance of the class is being used to forward data from another TCP/IP client.

OpenTerminal Method (SSHClient Class)

Creates a pseudo-terminal to be used to help display data for a channel.

Syntax

public void openTerminal(String channelId, String terminalType, int width, int height, boolean usePixels, String modes);

Remarks

OpenTerminal is used to establish a pseudo-terminal that will encode data sent over a "session" channel. ChannelId identifies the channel that will receive the terminal. TerminalType identifies the terminal protocol. Currently, only "vt100" is recognized by the Secure Shell (SSH) protocol specification, but other terminal types may be implemented by SSH server vendors.

Width and Height represent the size of the terminal display. If UsePixels is True, they represent the size in pixels; otherwise, they represent the size in terms of fixed-width characters.

Modes is a list of encoded terminal modes. The encoding of these modes is defined in Section 8 of the SSH Connection Specification (RFC 4254). The modes are encoded to a string as opcode-argument pairs. The opcode is always a single byte. For opcodes 1-159, the argument is a 32-bit integer. Opcodes 160-255 are currently undefined. Opcode '0' terminates the string.

Note: a string containing a single NULL byte (ie the character literal '\0') represents an empty mode list.

The following opcodes are defined:


0	TTY_OP_END Indicates end of options.
1	VINTR Interrupt character; 255 if none. Similarly for the other characters. Not all of these characters are supported on all systems.
2	VQUIT The quit character (sends SIGQUIT signal on POSIX systems).
3	VERASE Erase the character to left of the cursor.
4	VKILL Kill the current input line.
5	VEOF End-of-file character (sends EOF from the terminal).
6	VEOL End-of-line character in addition to carriage return and/or linefeed.
7	VEOL2 Additional end-of-line character.
8	VSTART Continues paused output (normally control-Q).
9	VSTOP Pauses output (normally control-S).
10	VSUSP Suspends the current program.
11	VDSUSP Another suspend character.
12	VREPRINT Reprints the current input line.
13	VWERASE Erases a word left of cursor.
14	VLNEXT Enter the next character typed literally, even if it is a special character
15	VFLUSH Character to flush output.
16	VSWTCH Switch to a different shell layer.
17	VSTATUS Prints system status line (e.g., load, command, pid).
18	VDISCARD Toggles the flushing of terminal output.
30	IGNPAR The ignore parity flag. The parameter SHOULD be 0 if this flag is False, and 1 if it is True.
31	PARMRK Mark parity and framing errors.
32	INPCK Enable checking of parity errors.
33	ISTRIP Strip 8th bit off characters.
34	INLCR Map NL into CR on input.
35	IGNCR Ignore CR on input.
36	ICRNL Map CR to NL on input.
37	IUCLC Translate uppercase characters to lowercase.
38	IXON Enable output flow control.
39	IXANY Any chararcter will restart after stop.
40	IXOFF Enable input flow control.
41	IMAXBEL Ring bell on input queue full.
50	ISIG Enable signals INTR, QUIT, and [D]SUSP.
51	ICANON Canonicalize input lines.
52	XCASE Enable input and output of uppercase characters by preceding their lowercase equivalents with "\".
53	ECHO Enable echoing.
54	ECHOE Visually erase characters.
55	ECHOK Kill character discards current line.
56	ECHONL Echo NL even if ECHO is off.
57	NOFLSH Do not flush after interrupt.
58	TOSTOP Stop background jobs from output.
59	IEXTEN Enable extensions.
60	ECHOCTL Echo control characters as ^(Char).
61	ECHOKE Visual erase for line kill.
62	PENDIN Retype pending input.
70	OPOST Enable output processing.
71	OLCUC Convert lowercase to uppercase.
72	ONLCR Map NL to CR-NL.
73	OCRNL Translate carriage return to newline (output).
74	ONOCR Translate newline to carriage return-newline (output).
75	ONLRET Newline performs a carriage return (output).
90	CS7 7-bit mode.
91	CS8 8-bit mode.
92	PARENB Parity enable.
93	PARODD Odd parity, else even.
128	TTY_OP_ISPEED Specifies the input baud rate in bits per second.
129	TTY_OP_OSPEED Specifies the output baud rate in bits per second.

Reset Method (SSHClient Class)

This method will reset the class.

Syntax

public void reset();

Remarks

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

SendBytes Method (SSHClient Class)

Sends binary data to the specified channel.

Syntax

public void sendBytes(String channelId, byte[] data);

Remarks

This method sends binary data to the channel identified by ChannelId. To send text, use the SendText method instead.

SendChannelData Method (SSHClient Class)

Sends data over a Secure Shell (SSH) channel.

Syntax

public void sendChannelData(String channelId, byte[] data);

Remarks

This method can be used to send arbitrary data to the channel with the specified ChannelId.

SendSSHPacket Method (SSHClient Class)

Sends an encoded Secure Shell (SSH) packet to the server.

Syntax

public void sendSSHPacket(String channelId, int packetType, byte[] payload);

Remarks

This method can be used to send a previously built SSH payload to the server. ChannelId identifies the channel that will receive the packet.

PacketType identifies what kind of packet is to be sent. Payload should contain the payload of the packet, which can be built by successive calls to SetSSHParam.

When SendSSHPacket is called, the class will finish building the packet, encrypt it for transport, and send it to the server.

SendText Method (SSHClient Class)

Sends text to the specified channel.

Syntax

public void sendText(String channelId, String text);

Remarks

This method sends text to the client identified by ChannelId. To send binary data use the SendBytes method instead.

SetSSHParam Method (SSHClient Class)

Writes 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 a Secure Shell (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 (e.g., "A1B23C")
m	A variable-length large integer, encoded as a textual representation of the value (e.g., "1234").
i	A 32-bit integer, encoded as a textual representation of the value (e.g., "1234").
l	A 64-bit integer, encoded as a textual representation of the value (e.g., "1234").
b	A single byte, encoded as a textual representation of the value (e.g., "123").
f	A boolean flag, encoded as a textual representation of the value (e.g., 'True' or 'False')

Note: Integer values may be hexadecimal encoded by prefixing "0x" to the beginning of the string; otherwise, the value is assumed to be Base10.

SSHLogoff Method (SSHClient Class)

Logs off from the Secure Shell (SSH) server.

Syntax

public void SSHLogoff();

Remarks

Logs off from the SSH server. If that fails, the connection is terminated by the local host.

SSHLogon Method (SSHClient Class)

Logs on to the SSHHost using the current SSHUser and SSHPassword .

Syntax

public void SSHLogon(String SSHHost, int SSHPort);

Remarks

Logs on to the Secure Shell (SSH) server using the current SSHUser and SSHPassword. This will perform the SSH handshake and authentication.

Example. Logging On:

SSHClient.SSHUser = "username" SSHClient.SSHPassword = "password" SSHClient.SSHLogon("sshHost", sshPort)

StartService Method (SSHClient Class)

Requests the given service on a target channel.

Syntax

public void startService(String channelId, String service, String parameter);

Remarks

After a "session" channel has been opened by a call to OpenChannel, a service may be requested for that channel. ChannelId identifies the channel on which the service is to be started.

Service identifies the service being requested. The following list defines some known services:


"shell"	Starts a shell on the target channel.
"exec"	Executes the command identified by `Parameter`.
"subsystem"	Starts up a subsystem identified by `Parameter`, such as "sftp".

Connected Event (SSHClient Class)

Fired immediately after a connection completes (or fails).

Syntax

public class DefaultSSHClientEventListener implements SSHClientEventListener {
  ...
  public void connected(SSHClientConnectedEvent e) {}
  ...
}

public class SSHClientConnectedEvent {
  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 Transmission Control Protocol (TCP)/IP stack. Description contains a description of this code. The value of StatusCode is equal to the value of the error.

Please refer to the Error Codes section for more information.

ConnectionStatus Event (SSHClient Class)

Fired to indicate changes in the connection state.

Syntax

public class DefaultSSHClientEventListener implements SSHClientEventListener {
  ...
  public void connectionStatus(SSHClientConnectionStatusEvent e) {}
  ...
}

public class SSHClientConnectionStatusEvent {
  public String connectionEvent;
  public int statusCode;
  public String description;
}

Remarks

This event is fired when the connection state changes: for example, completion of a firewall or proxy connection or completion of a security handshake.

The ConnectionEvent parameter indicates the type of connection event. Values may include the following:


	Firewall connection complete.
	Secure Sockets Layer (SSL) or S/Shell handshake complete (where applicable).
	Remote host connection complete.
	Remote host disconnected.
	SSL or S/Shell connection broken.
	Firewall host disconnected.

StatusCode has the error code returned by the Transmission Control Protocol (TCP)/IP stack. Description contains a description of this code. The value of StatusCode is equal to the value of the error.

Disconnected Event (SSHClient Class)

Fired when a connection is closed.

Syntax

public class DefaultSSHClientEventListener implements SSHClientEventListener {
  ...
  public void disconnected(SSHClientDisconnectedEvent e) {}
  ...
}

public class SSHClientDisconnectedEvent {
  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 Transmission Control Protocol (TCP/IP) subsystem. Description contains a description of this code. The value of StatusCode is equal to the value of the TCP/IP error.

Please refer to the Error Codes section for more information.

Error Event (SSHClient Class)

Fired when information is available about errors during data delivery.

Syntax

public class DefaultSSHClientEventListener implements SSHClientEventListener {
  ...
  public void error(SSHClientErrorEvent e) {}
  ...
}

public class SSHClientErrorEvent {
  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.

The ErrorCode parameter contains an error code, and the Description parameter 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 (SSHClient Class)

Fired once for each log message.

Syntax

public class DefaultSSHClientEventListener implements SSHClientEventListener {
  ...
  public void log(SSHClientLogEvent e) {}
  ...
}

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

Remarks

Fired once for each log message generated by the class. The verbosity is controlled by the LogLevel setting.

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


0 (None)	No messages are logged.
1 (Info - Default)	Informational events such as Secure Shell (SSH) handshake messages are logged.
2 (Verbose)	Detailed data such as individual packet information are 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.

SSHChannelClosed Event (SSHClient Class)

Fired when a channel is closed.

Syntax

public class DefaultSSHClientEventListener implements SSHClientEventListener {
  ...
  public void SSHChannelClosed(SSHClientSSHChannelClosedEvent e) {}
  ...
}

public class SSHClientSSHChannelClosedEvent {
  public String channelId;
}

Remarks

The SSHChannelClosed event is fired when a channel is closed on a Secure Shell (SSH) connection.

Note: Processing long-running requests, including sending channel data, inside this event may cause the underlying transport to stop processing Secure Shell (SSH) data until the event returns. To prevent this from happening, all requests should be processed asynchronously in a separate thread outside of this event.

SSHChannelData Event (SSHClient Class)

Fired when the SSHHost sends channel data to the client.

Syntax

public class DefaultSSHClientEventListener implements SSHClientEventListener {
  ...
  public void SSHChannelData(SSHClientSSHChannelDataEvent e) {}
  ...
}

public class SSHClientSSHChannelDataEvent {
  public String channelId;
  public byte[] channelData;
  public boolean channelDataEOLFound;
}

Remarks

The SSHChannelData event will fire as data are received for the given ChannelId. ChannelData will contain the decrypted contents of the Secure Shell (SSH) packet.

ChannelDataEOLFound indicates whether or not the ChannelEOL string for the channel was found at the end of ChannelData. If the ChannelEOL string was found, then ChannelDataEOLFound is True.

If ChannelData is part of a data portion of a length that is larger than the MaxChannelLength for the Channel with no ChannelEOL strings in it, then ChannelDataEOLFound is False.

Note: This means that one of more SSHChannelData events with ChannelDataEOLFound set to False can be received.

If the ChannelEOL property for the Channel is "" (empty string), then ChannelDataEOLFound can be disregarded (it is always True).

SSHChannelEOF Event (SSHClient Class)

Fired when the remote peer signals the end of the data stream for the channel.

Syntax

public class DefaultSSHClientEventListener implements SSHClientEventListener {
  ...
  public void SSHChannelEOF(SSHClientSSHChannelEOFEvent e) {}
  ...
}

public class SSHClientSSHChannelEOFEvent {
  public String channelId;
}

Remarks

The SSHChannelEOF event is fired when the end of the data stream for a channel on a Secure Shell (SSH) connection is reached.

SSHChannelOpened Event (SSHClient Class)

Fired when a channel is successfully opened.

Syntax

public class DefaultSSHClientEventListener implements SSHClientEventListener {
  ...
  public void SSHChannelOpened(SSHClientSSHChannelOpenedEvent e) {}
  ...
}

public class SSHClientSSHChannelOpenedEvent {
  public String channelId;
}

Remarks

The SSHChannelOpened event is fired when a channel is successfully opened on a Secure Shell (SSH) connection.

SSHChannelOpenRequest Event (SSHClient Class)

Fired when a host attempts to open a new channel.

Syntax

public class DefaultSSHClientEventListener implements SSHClientEventListener {
  ...
  public void SSHChannelOpenRequest(SSHClientSSHChannelOpenRequestEvent e) {}
  ...
}

public class SSHClientSSHChannelOpenRequestEvent {
  public String channelId;
  public String service;
  public byte[] parameters;
  public boolean accept; //read-write
}

Remarks

This event is fired whenever a host attempts to open a new channel. ChannelId will contain the Id of the channel to be created. Service will identify the type of channel that is being requested (e.g., "session"). Set Accept to True to accept the channel open request.

If the channel open request contains extra information, it will be contained in Parameters; you can extract data from it using GetSSHParam and GetSSHParamBytes. The most common example of a request with parameters would be a request with Service set to "direct-tcpip" for Secure Shell (SSH) tunneling; in that case, Parameters will contain the host to connect (string), the port to connect (int), the originator IP address (string), and the originator Transmission Control Protocol (TCP) port (int).

SSHChannelReadyToSend Event (SSHClient Class)

Fired when the class is ready to send data.

Syntax

public class DefaultSSHClientEventListener implements SSHClientEventListener {
  ...
  public void SSHChannelReadyToSend(SSHClientSSHChannelReadyToSendEvent e) {}
  ...
}

public class SSHClientSSHChannelReadyToSendEvent {
  public String channelId;
}

Remarks

This event fires when data can be sent over the Secure Shell (SSH) Channel specified by ChannelId.

When a channel is opened, this event will fire after the channel is ready and data can be sent.

When Timeout is set to 0 (asynchronous) sending data may result in an error if the channel or underlying socket cannot accept more data to send. Monitor SSHChannelReadyToSend or ReadyToSend to determine when data can be sent again.

When Timeout is set to a positive value, the class will block when sending data until the data can be successfully sent and SSHChannelReadyToSend and ReadyToSend do not need to be monitored.

SSHChannelRequest Event (SSHClient Class)

Fired when the SSHHost sends a channel request to the client.

Syntax

public class DefaultSSHClientEventListener implements SSHClientEventListener {
  ...
  public void SSHChannelRequest(SSHClientSSHChannelRequestEvent e) {}
  ...
}

public class SSHClientSSHChannelRequestEvent {
  public String channelId;
  public String requestType;
  public byte[] packet;
  public boolean success; //read-write
}

Remarks

The SSHHost may send requests that affect the status of a particular SSHChannel. Some requests will be automatically handled by the class. Others, however, may need the attention of the user to be dealt with properly within the scope of the application.

ChannelId identifies the channel receiving the request.

Type will contain the type of the request. These types depend on the type of the channel. For example, a "session" channel executing a command on the remote shell may receive an "exit-status" request containing the return code of that command.

RequestData contains the remainder of the original Secure Shell (SSH) packet. If the request type has specific parameters, they can be parsed out of this data.

Success should be used to instruct the class to respond to the request with either a success or failure notification. If the request is successful, SSHChannelRequested will fire with the same information in case the request requires further processing.

SSHChannelRequested Event (SSHClient Class)

Fired if the SSHChannelRequest was successful; any further processing for the channel request should be done here.

Syntax

public class DefaultSSHClientEventListener implements SSHClientEventListener {
  ...
  public void SSHChannelRequested(SSHClientSSHChannelRequestedEvent e) {}
  ...
}

public class SSHClientSSHChannelRequestedEvent {
  public String channelId;
  public String requestType;
  public byte[] packet;
}

Remarks

ChannelId identifies the channel receiving the request.

RequestData contains the remainder of the original Secure Shell (SSH) packet. If the request type has specific parameters, they can be parsed out of this data.

SSHCustomAuth Event (SSHClient Class)

Fired when the class is doing a custom authentication.

Syntax

public class DefaultSSHClientEventListener implements SSHClientEventListener {
  ...
  public void SSHCustomAuth(SSHClientSSHCustomAuthEvent e) {}
  ...
}

public class SSHClientSSHCustomAuthEvent {
  public String packet; //read-write
}

Remarks

SSHCustomAuth is fired during the user authentication stage of the Secure Shell (SSH) logon process if SSHAuthMode is set to amCustom. Packet contains the last raw 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 (SSHClient Class)

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

Syntax

public class DefaultSSHClientEventListener implements SSHClientEventListener {
  ...
  public void SSHKeyboardInteractive(SSHClientSSHKeyboardInteractiveEvent e) {}
  ...
}

public class SSHClientSSHKeyboardInteractiveEvent {
  public String name;
  public String instructions;
  public String prompt;
  public String response; //read-write
  public boolean echoResponse;
}

Remarks

SSHKeyboardInteractive is fired during the user authentication stage of the Secure Shell (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 (SSHClient Class)

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

Syntax

public class DefaultSSHClientEventListener implements SSHClientEventListener {
  ...
  public void SSHServerAuthentication(SSHClientSSHServerAuthenticationEvent e) {}
  ...
}

public class SSHClientSSHServerAuthenticationEvent {
  public byte[] hostKey;
  public String fingerprint;
  public String keyAlgorithm;
  public String certSubject;
  public String certIssuer;
  public String status;
  public boolean accept; //read-write
}

Remarks

This event is fired when the client can decide whether or not to continue with the connection process. If the public key is known to be a valid key for the Secure Shell (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: 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. The following values are supported:

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 applicable only when KeyAlgorithm is "x509v3-sign-rsa" or "x509v3-sign-dss".

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

Status is reserved for future use.

SSHStatus Event (SSHClient Class)

Fired to track the progress of the secure connection.

Syntax

public class DefaultSSHClientEventListener implements SSHClientEventListener {
  ...
  public void SSHStatus(SSHClientSSHStatusEvent e) {}
  ...
}

public class SSHClientSSHStatusEvent {
  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.

The following fields are available:

Fields

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

The date on which this certificate becomes valid. Before this date, it is not valid. The date is localized to the system's time zone. The following example illustrates the format of an encoded date:

23-Jan-2000 15:00:00.

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

The date on which the certificate expires. After this date, the certificate will no longer be valid. The date is localized to the system's time zone. The following example illustrates the format of an encoded date:

23-Jan-2001 15:00:00.

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

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: ""

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: ""

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: ""

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: ""

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: ""

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. 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: ""

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

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: ""

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: ""

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

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

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

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

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

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 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"

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

StoreB
byte[]
Default Value: "MY"

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 field is used to specify the password needed to open the certificate store.

StoreType
int
Default Value: 0

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.

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

Comma-separated lists of alternative subject names for the certificate.

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

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: ""

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: ""

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 (read-only)
Default Value: ""

The text description of UsageFlags.

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

Digital Signature
Non-Repudiation
Key Encipherment
Data Encipherment
Key Agreement
Certificate Signing
CRL Signing
Encipher Only

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

UsageFlags
int (read-only)
Default Value: 0

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


0x80	Digital Signature
0x40	Non-Repudiation
0x20	Key Encipherment
0x10	Data Encipherment
0x08	Key Agreement
0x04	Certificate Signing
0x02	CRL Signing
0x01	Encipher Only

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: ""

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

Subject
String
Default Value: ""

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.

Encoded
String
Default Value: ""

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: ""

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.

Constructors

public Certificate();

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

public Certificate( certificateFile);

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

public Certificate( encoded);

Parses Encoded as an X.509 public key.

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

StoreType identifies the type of certificate store to use. See 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). The Subject parameter can also take an MD5, SHA-1, or SHA-256 thumbprint of the certificate to load in a "Thumbprint=value" format.

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

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 the 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.

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

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( storeType,  store,  storePassword,  subject);

StoreType identifies the type of certificate store to use. See for descriptions of the different certificate stores. Store is a byte array containing the certificate data. StorePassword is the password used to protect the store.

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

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

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.

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.

The following fields are available:

Fields

AutoDetect
boolean
Default Value: False

Whether 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

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: ""

The name or IP address of the 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: ""

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

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: ""

A username if authentication is to be used when connecting through a firewall. If Host is specified, this field and the Password field are used to connect and authenticate to the given Firewall. If the authentication fails, the class throws an exception.

Constructors

public Firewall();

SSHChannel Type

Describes a currently open Secure Shell (SSH) channel.

Remarks

This type describes the Secure Shell (SSH) client's currently open channels. You may use the different fields for this type to manage the channel.

The following fields are available:

Fields

ChannelEOL
String
Default Value: ""

Breaks the incoming data stream into chunks separated by EOL.

This property is a binary string. Notably, this means that it can be more than one byte long, and it can contain NULL bytes.

ChannelEOL and MaxChannelLength must be set together or unexpected behavior could occur.

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

This field provides an Id generated by the class to identify the current Secure Shell (SSH) channel.

This Id is unique to this channel.

MaxChannelLength
int
Default Value: 0

This field specifies the maximum amount of data to accumulate when no EOL is found.

MaxChannelLength is the size of an internal buffer, which holds received data while waiting for a ChannelEOL string.

If the ChannelEOL string is found in the input stream before MaxChannelLength bytes are received, the SSHChannelData event is fired with the ChannelDataEOLFound parameter set to True, and the buffer is reset.

If no ChannelEOL is found, and MaxChannelLength bytes are accumulated in the buffer, the SSHChannelData event is fired with the ChannelDataEOLFound parameter set to False, and the buffer is reset.

ChannelEOL and MaxChannelLength must be set together or unexpected behavior could occur.

ReadyToSend
boolean (read-only)
Default Value: False

This field is True when data can be sent over the Secure Shell (SSH) channel.

When Timeout is set to a positive value, the class will block when sending data until the data can be successfully sent and SSHChannelReadyToSend and ReadyToSend do not need to be monitored.

RecordLength
int (read-only)
Default Value: 0

This field holds the current record length set by ChangeRecordLength. When this value is a positive number, the class will accumulate data until RecordLength is reached and only then will it fire the SSHChannelDataIn 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 by calling ChangeRecordLength, including within the SSHChannelDataIn event.

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

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

This field holds the channel type that was requested when opening the channel. For instance "session" or "forwarded-tcpip".

Config Settings (SSHClient 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.

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 is greater than 0 and ChannelDataEOL is a nonempty 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 configuration setting is valid only when queried inside SSHChannelData, MaxChannelDataLength > 0, and ChannelDataEOL is nonempty.

ClientSSHVersionString: The SSH version string used by the class.

This configuration setting specifies the Secure Shell (SSH) version string used by the class. The default value is "SSH-2.0-IPWorks SSH Client 2024".

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

DoNotRepeatAuthMethods: Whether the class will repeat authentication methods during multifactor authentication.

The default value is true. When set to false, the class will repeat authentication methods that have already been completed during multifactor authentication.

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

This configuration 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 as follows:


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

Note: This functionality is available only 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: 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 Secure Shell (SSH) key renegotiation. The default value for this property is set to 1 GB.

Example. Setting the Threshold to 500 MB: SSHComponent.Config("KeyRenegotiationThreshold=524288000")

LogLevel: Specifies the level of detail that is logged.

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


0 (None)	No messages are logged.
1 (Info - Default)	Informational events such as Secure Shell (SSH) handshake messages are logged.
2 (Verbose)	Detailed data such as individual packet information are 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 configuration 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 configuration setting specifies how many bytes of channel data can be sent to the sender of this message without adjusting the window.

Note: 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.

This configuration setting specifies 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 configuration 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 autofilled 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 configuration setting 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 configuration setting defines the length of data records to be received. The class will accumulate data until RecordLength is reached and only then will it 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 configuration setting 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 certificate authority (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 previous 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 configuration 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 configuration setting 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 2. Accepting Fingerprints: 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 as follows:

MD5
SHA1
SHA256 (default)

SSHFingerprintMD5: The server hostkey's MD5 fingerprint.

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

SSHFingerprintSHA1: The server hostkey's SHA1 fingerprint.

This configuration setting may be queried in SSHServerAuthentication to get the server hostkey's SHA-1 fingerprint.

SSHFingerprintSHA256: The server hostkey's SHA256 fingerprint.

This configuration setting may be queried in SSHServerAuthentication to get the server hostkey's SHA-256 fingerprint.

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

This configuration 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 configuration 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 configuration setting takes effect only when there is no activity; if any data are 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 configuration setting may be used to specify the list of supported key exchange algorithms used during Secure Shell (SSH) negotiation. The value should contain a comma-separated list of algorithms. Supported algorithms are as follows:

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

Example 3. Renegotiating SSH Keys: SSHClient.Config("SSHKeyRenegotiate")

SSHMacAlgorithms: Specifies the supported Mac algorithms.

This configuration setting 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 as follows:

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
hmac-sha2-256-96-etm@openssh.com
hmac-sha2-512-96-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 as follows:

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 because 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 that support them.

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

This configuration 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 following 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 configuration 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.

Because 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 as follows:


`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 will 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 continue only if the selected encryption and message authentication code (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 configuration 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 configuration 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 it 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 configuration 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 it 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 in which 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 configuration 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. 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.

Possible 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.

In multihomed 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 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 multihomed hosts (machines with more than one IP interface).

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

This configuration setting 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 configuration setting is useful when trying to connect to services that require a trusted port on 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 set to True, the socket will send all data that are ready to send at once. When set to False, the socket will send smaller buffered packets of data at small intervals. This is known as the Nagle algorithm.

By default, this configuration setting 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 as follows:


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 that 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 User Datagram Protocol (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 Transmission Control Protocol (TCP)/IP stack. You can increase or decrease its size depending on the amount of data that you will be receiving. In some cases, increasing the value of the InBufferSize setting can provide significant improvements in performance.

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. In some cases, increasing the value of the OutBufferSize setting can provide significant improvements in performance.

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.

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.

MaskSensitiveData: 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 Federal Information Processing Standards (FIPS), while all 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.

The following classes must be imported in the application in which the component will be used:

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, Secure Sockets Layer (SSL)-enabled classes can optionally be configured to use the Transport Layer Security (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 Bouncy Castle FIPS provider 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.

The following classes must be imported in the application in which the component will be used:

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 also must 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 that 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 (SSHClient Class)

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 nonsocket.
10039	[10039] Destination address required.
10040	[10040] Message is too long.
10041	[10041] Protocol wrong type for socket.
10042	[10042] Bad protocol option.
10043	[10043] Protocol is not supported.
10044	[10044] Socket type is not supported.
10045	[10045] Operation is not supported on socket.
10046	[10046] Protocol family is not supported.
10047	[10047] Address family is not supported by protocol family.
10048	[10048] Address already in use.
10049	[10049] Cannot 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] Cannot send after socket shutdown.
10059	[10059] Too many references, cannot splice.
10060	[10060] Connection timed out.
10061	[10061] Connection refused.
10062	[10062] Too many levels of symbolic links.
10063	[10063] File name is too long.
10064	[10064] Host is down.
10065	[10065] No route to host.
10066	[10066] Directory is 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 is not loaded yet.
11001	[11001] Host not found.
11002	[11002] Nonauthoritative 'Host not found' (try again or check DNS setup).
11003	[11003] Nonrecoverable errors: FORMERR, REFUSED, NOTIMP.
11004	[11004] Valid name, no data record (check DNS setup).