Telnet Component

Properties   Methods   Events   Configuration Settings   Errors  

The Telnet Component is used to communicate with servers implementing the TELNET protocol.

Syntax

IPWorks.Telnet

Remarks

The Telnet Component supports both plaintext and SSL/TLS connections. When connecting over SSL/TLS the SSLServerAuthentication event allows you to check the server identity and other security attributes. The SSLStatus event provides information about the SSL handshake. Additional SSL related settings are also supported via the Config method.

The Telnet Component provides a simple interface to Telnet communications as specified by RFC 854. It allows sending of Telnet command codes to remote Telnet servers and it scans the input data for Telnet commands. Appropriate events are fired for received commands.

The connection interface is very similar to that of IPPort. The same properties and events are used for sending and receiving normal data, and the same property set is used for setting properties of the connection. The Telnet Component adds a number of properties like Command, DoOption, etc. which allow sending of Telnet commands to the other end. The respective events (Command, Do, etc.) are fired when the corresponding Telnet commands are received.

Property List


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

AcceptDataEnables or disables data reception (the DataIn event).
BytesSentThe number of bytes actually sent after an assignment to DataToSend .
CommandA single character Telnet command code to be sent to the server.
ConnectedTriggers a connection or disconnection.
DataToSendA string of data to be sent to the remote host.
DontOptionA single character Telnet option code to be sent to the server with the Telnet DONT command.
DoOptionA single character Telnet option code to be sent to the server with the Telnet DO command.
DoSubOptionA Telnet SubOption to send to the server with the SubOption command.
FirewallA set of properties related to firewall access.
KeepAliveWhen True, KEEPALIVE packets are enabled (for long connections).
LingerWhen set to True, connections are terminated gracefully.
LocalHostThe name of the local host or user-assigned IP interface through which connections are initiated or accepted.
LocalPortThe TCP port in the local host where IPPort binds.
RemoteHostThe address of the remote host. Domain names are resolved to IP addresses.
RemotePortThe secure Telnet port in the remote host (default is 23).
SSLAcceptServerCertInstructs the component to unconditionally accept the server certificate that matches the supplied certificate.
SSLCertThe certificate to be used during SSL negotiation.
SSLEnabledWhether TLS/SSL is enabled.
SSLServerCertThe server certificate for the last established connection.
SSLStartModeDetermines how the component starts the SSL negotiation.
TimeoutA timeout for the component.
TransparentWhen True, Telnet command processing is disabled.
UrgentDataA string of data to be sent urgently (out-of-band) to the remote host.
WillOptionA single character Telnet option code to be sent to the server with the Telnet WILL command.
WontOptionA single character Telnet option code to be sent to the server with the Telnet WONT command.

Method List


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

configSets or retrieves a configuration setting.
connectConnect to a remote host.
disconnectDisconnect from the remote host.
doEventsProcesses events from the internal message queue.
resetReset the component.
sendSend data to the remote host.

Event List


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

CommandFired when a Telnet command comes from the Telnet server.
ConnectedFired immediately after a connection completes (or fails).
ConnectionStatusFired to indicate changes in connection state.
DataInFired when data is received from the remote host.
DisconnectedFired when a connection is closed.
DoDoFired when a Telnet DO OPTION command comes from the Telnet server.
DontFired when a Telnet DONT OPTION command comes from the Telnet server.
ErrorInformation about errors during data delivery.
ReadyToSendFired when the component is ready to send data.
SSLServerAuthenticationFired after the server presents its certificate to the client.
SSLStatusShows the progress of the secure connection.
SubOptionFired when a Telnet SubOption command comes from the Telnet server.
WillFired when a Telnet WILL OPTION command comes from the Telnet server.
WontFired when a Telnet WONT OPTION command comes from the Telnet server.

Configuration Settings


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

CloseStreamAfterTransferIf true, the component will close the upload or download stream after the transfer.
ConnectionTimeoutSets a separate timeout value for establishing a connection.
FirewallAutoDetectTells the component whether or not to automatically detect and use firewall system settings, if available.
FirewallHostName or IP address of firewall (optional).
FirewallListenerIf true, the component binds to a SOCKS firewall as a server (IPPort only).
FirewallPasswordPassword to be used if authentication is to be used when connecting through the firewall.
FirewallPortThe TCP port for the FirewallHost;.
FirewallTypeDetermines the type of firewall to connect through.
FirewallUserA user name if authentication is to be used connecting through a firewall.
KeepAliveIntervalThe retry interval, in milliseconds, to be used when a TCP keep-alive packet is sent and no response is received.
KeepAliveTimeThe inactivity time in milliseconds before a TCP keep-alive packet is sent.
LingerWhen set to True, connections are terminated gracefully.
LingerTimeTime in seconds to have the connection linger.
LocalHostThe name of the local host through which connections are initiated or accepted.
LocalPortThe port in the local host where the component binds.
MaxLineLengthThe maximum amount of data to accumulate when no EOL is found.
MaxTransferRateThe transfer rate limit in bytes per second.
ProxyExceptionsListA semicolon separated list of hosts and IPs to bypass when using a proxy.
TCPKeepAliveDetermines whether or not the keep alive socket option is enabled.
TcpNoDelayWhether or not to delay when sending packets.
UseIPv6Whether to use IPv6.
UseNTLMv2Whether to use NTLM V2.
LogSSLPacketsControls whether SSL packets are logged when using the internal security API.
ReuseSSLSessionDetermines if the SSL session is reused.
SSLCACertsA newline separated list of CA certificate to use during SSL client authentication.
SSLCipherStrengthThe minimum cipher strength used for bulk encryption.
SSLContextProtocolThe protocol used when getting an SSLContext instance.
SSLEnabledCipherSuitesThe cipher suite to be used in an SSL negotiation.
SSLEnabledProtocolsUsed to enable/disable the supported security protocols.
SSLEnableRenegotiationWhether the renegotiation_info SSL extension is supported.
SSLIncludeCertChainWhether the entire certificate chain is included in the SSLServerAuthentication event.
SSLProviderThe name of the security provider to use.
SSLServerCACertsA newline separated list of CA certificate to use during SSL server certificate validation.
SSLTrustManagerFactoryAlgorithmThe algorithm to be used to create a TrustManager through TrustManagerFactory.
TLS12SignatureAlgorithmsDefines the allowed TLS 1.2 signature algorithms when UseInternalSecurityAPI is True.
TLS12SupportedGroupsThe supported groups for ECC.
TLS13KeyShareGroupsThe groups for which to pregenerate key shares.
TLS13SignatureAlgorithmsThe allowed certificate signature algorithms.
TLS13SupportedGroupsThe supported groups for (EC)DHE key exchange.
AbsoluteTimeoutDetermines whether timeouts are inactivity timeouts or absolute timeouts.
FirewallDataUsed to send extra data to the firewall.
InBufferSizeThe size in bytes of the incoming queue of the socket.
OutBufferSizeThe size in bytes of the outgoing queue of the socket.
BuildInfoInformation about the product's build.
GUIAvailableTells the component whether or not a message loop is available for processing events.
LicenseInfoInformation about the current license.
UseDaemonThreadsWhether threads created by the component are daemon threads.
UseInternalSecurityAPITells the component whether or not to use the system security libraries or an internal implementation.

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IPWorks 2020 Android Edition - Version 20.0 [Build 7941]