# SSHServer Class The SSHServer class is used to create Secure Shell (SSH) servers. The class handles multiple simultaneous connections on the same Transmission Control Protocol (TCP)/IP port (service port). It is designed to balance the load between connections for a fast, powerful server. ## Syntax ```text class ipworksssh.SSHServer ``` ## Remarks The SSHServer class is the Secure Shell (SSH)-enabled equivalent of the IPWorks TCPServer class, extended by a set of new properties and events that deal with SSH security. The [ssh_compression_algorithms](#ssh_compression_algorithms-property) and [ssh_encryption_algorithms](#ssh_encryption_algorithms-property) properties determine which protocols are enabled for the SSH handshake. The ssh_cert* properties are used to select a certificate for the server (note that a valid certificate **must** be selected before the server can function). The [on_ssh_user_auth_request](#on_ssh_user_auth_request-event) event will allow you to use authenticate clients using digital certificates or passwords. Finally, the [on_ssh_status](#on_ssh_status-event) event provides information about the SSH handshake and underlying protocol notifications. By default, each instance of SSHServer can handle up to 1000 simultaneous incoming connections (this number may be increased up to 100,000, or decreased to a lower value by using the [MaxConnections](#MaxConnections) configuration setting). SSH connections are identified by a *ConnectionId*. Events relating to these connections as a whole will use the *ConnectionId* to identify the specific connection. Connections may also contain one or more multiplexed channels, which are identified by a *ChannelId*. Channel-level events will specify the *ChannelId* to which they relate. SSHServer can start to listen on a port by setting the [listening](#listening-property) property to True. When a remote host asks for a connection, the [on_connection_request](#on_connection_request-event) event is fired. At that point, the connection can either be accepted or rejected. If the connection is accepted, a *ConnectionId* is assigned, and communication can start. From this point on, the operation is similar to SSHClient. Data can be sent to an individual SSHChannel using [send_channel_data](#send_channel_data-method). The address and port of the incoming connection can be found by querying the [client_remote_host](#SSHServer_p_ClientRemoteHost) and [client_remote_port](#SSHServer_p_ClientRemotePort) properties. NOTE: Server components are designed to process events as they occur. To ensure that events are processed in a timely manner, [do_events](#do_events-method) should be called in a loop after the server is started. ## Property List *The following is the full list of the properties of the class with short descriptions. Click on the links for further details.* | | | | --- | --- | | [ssh_channel_count](#ssh_channel_count-property) | The number of records in the arrays. | | [bytes_sent](#bytes_sent-property) | This property specifies the number of bytes actually sent after a sending channel data. | | [channel_eol](#channel_eol-property) | Breaks the incoming data stream into chunks separated by EOL . | | [channel_id](#channel_id-property) | This property provides an Id generated by the class to identify the current Secure Shell (SSH) channel. | | [max_channel_length](#max_channel_length-property) | This property specifies the maximum amount of data to accumulate when no EOL is found. | | [ready_to_send](#ready_to_send-property) | This property is True when data can be sent over the Secure Shell (SSH) channel. | | [record_length](#record_length-property) | This property holds the current record length set by ChangeRecordLength . | | [service](#service-property) | This property holds the channel type that was requested when opening the channel. | | [ssh_connection_count](#ssh_connection_count-property) | The number of records in the SSHConnection arrays. | | [ssh_connection_connected](#ssh_connection_connected-property) | This property indicates the status of individual connections. | | [ssh_connection_local_address](#ssh_connection_local_address-property) | This property shows the IP address of the interface through which the connection is passing. | | [ssh_connection_remote_host](#ssh_connection_remote_host-property) | The RemoteHost shows the IP address of the remote host through which the connection is coming. | | [ssh_connection_remote_port](#ssh_connection_remote_port-property) | The RemotePort shows the Transmission Control Protocol (TCP) port on the remote host through which the connection is coming. | | [ssh_connection_timeout](#ssh_connection_timeout-property) | This property contains a timeout for the class. | | [connection_backlog](#connection_backlog-property) | This property includes the maximum number of pending connections maintained by the Transmission Control Protocol (TCP)/IP subsystem. | | [default_auth_methods](#default_auth_methods-property) | The supported authentication methods. | | [default_idle_timeout](#default_idle_timeout-property) | This property includes the default idle timeout for inactive clients. | | [default_timeout](#default_timeout-property) | The initial timeout value to be used by incoming connections. | | [keyboard_interactive_message](#keyboard_interactive_message-property) | The instructions to send to the client during keyboard-interactive authentication. | | [keyboard_interactive_prompt_count](#keyboard_interactive_prompt_count-property) | The number of records in the KeyboardInteractivePrompt arrays. | | [keyboard_interactive_prompt_echo](#keyboard_interactive_prompt_echo-property) | This property specifies whether or not the client should echo the value entered by the user. | | [keyboard_interactive_prompt_prompt](#keyboard_interactive_prompt_prompt-property) | This property contains the prompt label or text the client should present to the user. | | [listening](#listening-property) | This property indicates whether the class is listening for incoming connections on LocalPort. | | [local_host](#local_host-property) | The name of the local host or user-assigned IP interface through which connections are initiated or accepted. | | [local_port](#local_port-property) | The Transmission Control Protocol (TCP) port in the local host where the class listens. | | [ssh_cert_count](#ssh_cert_count-property) | The number of records in the SSHCert arrays. | | [ssh_cert_effective_date](#ssh_cert_effective_date-property) | The date on which this certificate becomes valid. | | [ssh_cert_encoded](#ssh_cert_encoded-property) | The certificate (PEM/Base64 encoded). | | [ssh_cert_expiration_date](#ssh_cert_expiration_date-property) | The date on which the certificate expires. | | [ssh_cert_extended_key_usage](#ssh_cert_extended_key_usage-property) | A comma-delimited list of extended key usage identifiers. | | [ssh_cert_fingerprint](#ssh_cert_fingerprint-property) | The hex-encoded, 16-byte MD5 fingerprint of the certificate. | | [ssh_cert_fingerprint_sha1](#ssh_cert_fingerprint_sha1-property) | The hex-encoded, 20-byte SHA-1 fingerprint of the certificate. | | [ssh_cert_fingerprint_sha256](#ssh_cert_fingerprint_sha256-property) | The hex-encoded, 32-byte SHA-256 fingerprint of the certificate. | | [ssh_cert_issuer](#ssh_cert_issuer-property) | The issuer of the certificate. | | [ssh_cert_private_key](#ssh_cert_private_key-property) | The private key of the certificate (if available). | | [ssh_cert_private_key_available](#ssh_cert_private_key_available-property) | Whether a PrivateKey is available for the selected certificate. | | [ssh_cert_private_key_container](#ssh_cert_private_key_container-property) | The name of the PrivateKey container for the certificate (if available). | | [ssh_cert_public_key](#ssh_cert_public_key-property) | The public key of the certificate. | | [ssh_cert_public_key_algorithm](#ssh_cert_public_key_algorithm-property) | The textual description of the certificate's public key algorithm. | | [ssh_cert_public_key_length](#ssh_cert_public_key_length-property) | The length of the certificate's public key (in bits). | | [ssh_cert_serial_number](#ssh_cert_serial_number-property) | The serial number of the certificate encoded as a string. | | [ssh_cert_signature_algorithm](#ssh_cert_signature_algorithm-property) | The text description of the certificate's signature algorithm. | | [ssh_cert_store](#ssh_cert_store-property) | The name of the certificate store for the client certificate. | | [ssh_cert_store_password](#ssh_cert_store_password-property) | If the type of certificate store requires a password, this property is used to specify the password needed to open the certificate store. | | [ssh_cert_store_type](#ssh_cert_store_type-property) | The type of certificate store for this certificate. | | [ssh_cert_subject](#ssh_cert_subject-property) | The subject of the certificate used for client authentication. | | [ssh_cert_subject_alt_names](#ssh_cert_subject_alt_names-property) | Comma-separated lists of alternative subject names for the certificate. | | [ssh_cert_thumbprint_md5](#ssh_cert_thumbprint_md5-property) | The MD5 hash of the certificate. | | [ssh_cert_thumbprint_sha1](#ssh_cert_thumbprint_sha1-property) | The SHA-1 hash of the certificate. | | [ssh_cert_thumbprint_sha256](#ssh_cert_thumbprint_sha256-property) | The SHA-256 hash of the certificate. | | [ssh_cert_usage](#ssh_cert_usage-property) | The text description of UsageFlags . | | [ssh_cert_usage_flags](#ssh_cert_usage_flags-property) | The flags that show intended use for the certificate. | | [ssh_cert_version](#ssh_cert_version-property) | The certificate's version number. | | [ssh_compression_algorithms](#ssh_compression_algorithms-property) | The comma-separated list containing all allowable compression algorithms. | | [ssh_encryption_algorithms](#ssh_encryption_algorithms-property) | The comma-separated list containing all allowable encryption algorithms. | ## Method List *The following is the full list of the methods of the class with short descriptions. Click on the links for further details.* | | | | --- | --- | | [change_record_length](#change_record_length-method) | Changes the length of received data records. | | [close_channel](#close_channel-method) | Closes an existing SSHChannel . | | [config](#config-method) | Sets or retrieves a configuration setting. | | [disconnect](#disconnect-method) | This method disconnects the specified client. | | [do_events](#do_events-method) | This method processes events from the internal message queue. | | [exchange_keys](#exchange_keys-method) | Causes the class to exchange a new set of session keys on the specified connection. | | [get_ssh_param](#get_ssh_param-method) | Reads a field from a Secure Shell (SSH) packet's payload. | | [get_ssh_param_bytes](#get_ssh_param_bytes-method) | Reads a field from a Secure Shell (SSH) packet's payload. | | [open_channel](#open_channel-method) | Opens a new SSHChannel . | | [reset](#reset-method) | This method will reset the class. | | [send_bytes](#send_bytes-method) | Sends binary data to the specified channel. | | [send_channel_data](#send_channel_data-method) | Sends data over a Secure Shell (SSH) channel. | | [send_ssh_packet](#send_ssh_packet-method) | Sends an encoded Secure Shell (SSH) packet to the server. | | [send_text](#send_text-method) | Sends text to the specified channel. | | [set_ssh_param](#set_ssh_param-method) | Writes a field to the end of a payload. | | [shutdown](#shutdown-method) | This method shuts down the server. | | [start_listening](#start_listening-method) | This method starts listening for incoming connections. | | [stop_listening](#stop_listening-method) | This method stops listening for new connections. | ## Event List *The following is the full list of the events fired by the class with short descriptions. Click on the links for further details.* | | | | --- | --- | | [on_connected](#on_connected-event) | Fired immediately after a connection completes (or fails). | | [on_connection_request](#on_connection_request-event) | This event is fired when a request for connection comes from a remote host. | | [on_disconnected](#on_disconnected-event) | This event is fired when a connection is closed. | | [on_error](#on_error-event) | Fired when errors occur during data delivery. | | [on_log](#on_log-event) | Fired once for each log message. | | [on_ssh_channel_closed](#on_ssh_channel_closed-event) | Fired when a channel is closed. | | [on_ssh_channel_data_in](#on_ssh_channel_data_in-event) | Fired when data are received on a Secure Shell (SSH) channel. | | [on_ssh_channel_eof](#on_ssh_channel_eof-event) | Fired when the remote peer signals the end of the data stream for the channel. | | [on_ssh_channel_opened](#on_ssh_channel_opened-event) | Fired when a channel is successfully opened. | | [on_ssh_channel_open_request](#on_ssh_channel_open_request-event) | Fired when a client attempts to open a new channel. | | [on_ssh_channel_ready_to_send](#on_ssh_channel_ready_to_send-event) | Fired when the class is ready to send data. | | [on_ssh_channel_request](#on_ssh_channel_request-event) | Fired when the client sends a channel request to the SSHHost . | | [on_ssh_channel_requested](#on_ssh_channel_requested-event) | Fired if the SSHChannelRequest was successful, any further processing for the channel request should be done here. | | [on_ssh_service_request](#on_ssh_service_request-event) | Fired when a client requests a service to be started. | | [on_ssh_status](#on_ssh_status-event) | Fired to show the progress of the secure connection. | | [on_ssh_tunnel_closed](#on_ssh_tunnel_closed-event) | Fired when a connected client attempts to close a tunnel. | | [on_ssh_tunnel_requested](#on_ssh_tunnel_requested-event) | Fired when a connected client attempts to establish a forward or reverse tunnel. | | [on_ssh_user_auth_request](#on_ssh_user_auth_request-event) | Fired when a client attempts to authenticate a connection. | ## Config Settings *The following is a list of config settings for the class with short descriptions. Click on the links for further details.* | | | | --- | --- | | [AltSSHCertCount](#AltSSHCertCount) | The number of records in the AltSSHCert configuration settings. | | [AltSSHCertStore\[i\]](#AltSSHCertStore[i]) | The name of the certificate store. | | [AltSSHCertStorePassword\[i\]](#AltSSHCertStorePassword[i]) | The password used to open the certificate store. | | [AltSSHCertStoreType\[i\]](#AltSSHCertStoreType[i]) | The type of certificate store. | | [AltSSHCertSubject\[i\]](#AltSSHCertSubject[i]) | The alternative certificate subject. | | [ClientSSHVersionString\[ConnectionId\]](#ClientSSHVersionString[ConnectionId]) | The client's version string. | | [FireAuthRequestAfterSig](#FireAuthRequestAfterSig) | Whether to fire an informational event after the public key signature has been verified. | | [KeyboardInteractivePrompts\[ConnectionId\]](#KeyboardInteractivePrompts[ConnectionId]) | Specifies custom keyboard-interactive prompts for particular connections. | | [KeyRenegotiationThreshold](#KeyRenegotiationThreshold) | Sets the threshold for the SSH Key Renegotiation. | | [LogLevel](#LogLevel) | Specifies the level of detail that is logged. | | [MaxAuthAttempts](#MaxAuthAttempts) | The maximum authentication attempts allowed before forcing a disconnect. | | [NegotiatedStrictKex\[ConnectionId\]](#NegotiatedStrictKex[ConnectionId]) | Returns whether strict key exchange was negotiated to be used. | | [ServerSSHVersionString](#ServerSSHVersionString) | The SSH version string sent to connecting clients. | | [SSHKeepAliveCountMax](#SSHKeepAliveCountMax) | The maximum number of keep alive packets to send without a response. | | [SSHKeepAliveInterval](#SSHKeepAliveInterval) | The interval between keep alive packets. | | [SSHKeyExchangeAlgorithms](#SSHKeyExchangeAlgorithms) | Specifies the supported key exchange algorithms. | | [SSHMacAlgorithms](#SSHMacAlgorithms) | Specifies the supported Mac algorithms. | | [SSHPubKeyAuthSigAlgorithms](#SSHPubKeyAuthSigAlgorithms) | Specifies the allowed signature algorithms used by a client performing public key authentication. | | [SSHPublicKeyAlgorithms](#SSHPublicKeyAlgorithms) | Specifies the supported public key algorithms for the server's public key. | | [SSHVersionPattern](#SSHVersionPattern) | The pattern used to match the remote host's version string. | | [UserAuthBanner\[ConnectionId\]](#UserAuthBanner[ConnectionId]) | A custom user authentication banner. | | [UseStrictKeyExchange](#UseStrictKeyExchange) | Specifies how strict key exchange is supported. | | [AllowedClients](#AllowedClients) | A comma-separated list of host names or IP addresses that can access the class. | | [BindExclusively](#BindExclusively) | Whether or not the class considers a local port reserved for exclusive use. | | [BlockedClients](#BlockedClients) | A comma-separated list of host names or IP addresses that cannot access the class. | | [ConnectionUID](#ConnectionUID) | The unique connectionId for a connection. | | [DefaultConnectionTimeout](#DefaultConnectionTimeout) | The inactivity timeout applied to the SSL handshake. | | [InBufferSize](#InBufferSize) | The size in bytes of the incoming queue of the socket. | | [KeepAliveInterval](#KeepAliveInterval) | The retry interval, in milliseconds, to be used when a TCP keep-alive packet is sent and no response is received. | | [KeepAliveRetryCount](#KeepAliveRetryCount) | The number of keep-alive packets to be sent before the remotehost is considered disconnected. | | [KeepAliveTime](#KeepAliveTime) | The inactivity time in milliseconds before a TCP keep-alive packet is sent. | | [MaxConnections](#MaxConnections) | The maximum number of connections available. | | [MaxReadTime](#MaxReadTime) | The maximum time spent reading data from each connection. | | [OutBufferSize](#OutBufferSize) | The size in bytes of the outgoing queue of the socket. | | [TcpNoDelay](#TcpNoDelay) | Whether or not to delay when sending packets. | | [UseIOCP](#UseIOCP) | Whether to use the completion port I/O model. | | [UseIPv6](#UseIPv6) | Whether to use IPv6. | | [UseWindowsMessages](#UseWindowsMessages) | Whether to use the WSAAsyncSelect I/O model. | | [BuildInfo](#BuildInfo) | Information about the product's build. | | [CodePage](#CodePage) | The system code page used for Unicode to Multibyte translations. | | [LicenseInfo](#LicenseInfo) | Information about the current license. | | [MaskSensitiveData](#MaskSensitiveData) | Whether sensitive data is masked in log messages. | | [ProcessIdleEvents](#ProcessIdleEvents) | Whether the class uses its internal event loop to process events when the main thread is idle. | | [SelectWaitMillis](#SelectWaitMillis) | The length of time in milliseconds the class will wait when DoEvents is called if there are no events to process. | | [UseFIPSCompliantAPI](#UseFIPSCompliantAPI) | Tells the class whether or not to use FIPS certified APIs. | | [UseInternalSecurityAPI](#UseInternalSecurityAPI) | Whether or not to use the system security libraries or an internal implementation. | # ssh_channel_count property The number of records in the arrays. ## Syntax ```text def get_ssh_channel_count() -> int: ... ssh_channel_count = property(get_ssh_channel_count, None) ``` ## Default Value 0 ## Remarks This property controls the size of the following arrays: - [bytes_sent](#bytes_sent-property) - [channel_eol](#channel_eol-property) - [channel_id](#channel_id-property) - [keyboard_interactive_prompt_echo](#keyboard_interactive_prompt_echo-property) - [keyboard_interactive_prompt_prompt](#keyboard_interactive_prompt_prompt-property) - [max_channel_length](#max_channel_length-property) - [ready_to_send](#ready_to_send-property) - [record_length](#record_length-property) - [service](#service-property) - [ssh_cert_effective_date](#ssh_cert_effective_date-property) - [ssh_cert_encoded](#ssh_cert_encoded-property) - [ssh_cert_expiration_date](#ssh_cert_expiration_date-property) - [ssh_cert_extended_key_usage](#ssh_cert_extended_key_usage-property) - [ssh_cert_fingerprint](#ssh_cert_fingerprint-property) - [ssh_cert_fingerprint_sha1](#ssh_cert_fingerprint_sha1-property) - [ssh_cert_fingerprint_sha256](#ssh_cert_fingerprint_sha256-property) - [ssh_cert_issuer](#ssh_cert_issuer-property) - [ssh_cert_private_key](#ssh_cert_private_key-property) - [ssh_cert_private_key_available](#ssh_cert_private_key_available-property) - [ssh_cert_private_key_container](#ssh_cert_private_key_container-property) - [ssh_cert_public_key](#ssh_cert_public_key-property) - [ssh_cert_public_key_algorithm](#ssh_cert_public_key_algorithm-property) - [ssh_cert_public_key_length](#ssh_cert_public_key_length-property) - [ssh_cert_serial_number](#ssh_cert_serial_number-property) - [ssh_cert_signature_algorithm](#ssh_cert_signature_algorithm-property) - [ssh_cert_store](#ssh_cert_store-property) - [ssh_cert_store_password](#ssh_cert_store_password-property) - [ssh_cert_store_type](#ssh_cert_store_type-property) - [ssh_cert_subject](#ssh_cert_subject-property) - [ssh_cert_subject_alt_names](#ssh_cert_subject_alt_names-property) - [ssh_cert_thumbprint_md5](#ssh_cert_thumbprint_md5-property) - [ssh_cert_thumbprint_sha1](#ssh_cert_thumbprint_sha1-property) - [ssh_cert_thumbprint_sha256](#ssh_cert_thumbprint_sha256-property) - [ssh_cert_usage](#ssh_cert_usage-property) - [ssh_cert_usage_flags](#ssh_cert_usage_flags-property) - [ssh_cert_version](#ssh_cert_version-property) - [ssh_connection_connected](#ssh_connection_connected-property) - [ssh_connection_local_address](#ssh_connection_local_address-property) - [ssh_connection_remote_host](#ssh_connection_remote_host-property) - [ssh_connection_remote_port](#ssh_connection_remote_port-property) - [ssh_connection_timeout](#ssh_connection_timeout-property) The array indices start at *0* and end at *ssh_channel_count - 1*. This property is read-only. # bytes_sent property This property specifies the number of bytes actually sent after a sending channel data. ## Syntax ```text def get_bytes_sent(ssh_channel_id: int) -> int: ... ``` ## Default Value 0 ## Remarks This property specifies the number of bytes actually sent after a sending channel data. The *ssh_channel_id* parameter specifies the index of the item in the array. The size of the array is controlled by the [ssh_channel_count](#ssh_channel_count-property) property. This property is read-only. # channel_eol property Breaks the incoming data stream into chunks separated by EOL . ## Syntax ```text def get_channel_eol(ssh_channel_id: int) -> str: ... def set_channel_eol(ssh_channel_id: int, value: str) -> None: ... ``` ## Default Value "" ## Remarks 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](#SSHServerpChannelEOL) and [maxchannellength](#SSHServerpMaxChannelLength) *must* be set together or unexpected behavior could occur. The *ssh_channel_id* parameter specifies the index of the item in the array. The size of the array is controlled by the [ssh_channel_count](#ssh_channel_count-property) property. # channel_id property This property provides an Id generated by the class to identify the current Secure Shell (SSH) channel. ## Syntax ```text def get_channel_id(ssh_channel_id: int) -> str: ... ``` ## Default Value "" ## Remarks This property provides an Id generated by the class to identify the current Secure Shell (SSH) channel. This Id is unique to this channel. The *ssh_channel_id* parameter specifies the index of the item in the array. The size of the array is controlled by the [ssh_channel_count](#ssh_channel_count-property) property. This property is read-only. # max_channel_length property This property specifies the maximum amount of data to accumulate when no EOL is found. ## Syntax ```text def get_max_channel_length(ssh_channel_id: int) -> int: ... def set_max_channel_length(ssh_channel_id: int, value: int) -> None: ... ``` ## Default Value 0 ## Remarks This property specifies the maximum amount of data to accumulate when no *EOL* is found. [maxchannellength](#SSHServerpMaxChannelLength) is the size of an internal buffer, which holds received data while waiting for a [channeleol](#SSHServerpChannelEOL) string. If the [channeleol](#SSHServerpChannelEOL) string is found in the input stream before MaxChannelLength bytes are received, the onsshchanneldata event is fired with the *ChannelDataEOLFound* parameter set to True, and the buffer is reset. If no [channeleol](#SSHServerpChannelEOL) is found, and [maxchannellength](#SSHServerpMaxChannelLength) bytes are accumulated in the buffer, the onsshchanneldata event is fired with the *ChannelDataEOLFound* parameter set to False, and the buffer is reset. [channeleol](#SSHServerpChannelEOL) and [maxchannellength](#SSHServerpMaxChannelLength) *must* be set together or unexpected behavior could occur. The *ssh_channel_id* parameter specifies the index of the item in the array. The size of the array is controlled by the [ssh_channel_count](#ssh_channel_count-property) property. # ready_to_send property This property is True when data can be sent over the Secure Shell (SSH) channel. ## Syntax ```text def get_ready_to_send(ssh_channel_id: int) -> bool: ... ``` ## Default Value FALSE ## Remarks This property is True when data can be sent over the Secure Shell (SSH) channel. 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 onsshchannelreadytosend or [readytosend](#SSHServerpReadyToSend) 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 onsshchannelreadytosend and [readytosend](#SSHServerpReadyToSend) do not need to be monitored. The *ssh_channel_id* parameter specifies the index of the item in the array. The size of the array is controlled by the [ssh_channel_count](#ssh_channel_count-property) property. This property is read-only. # record_length property This property holds the current record length set by ChangeRecordLength . ## Syntax ```text def get_record_length(ssh_channel_id: int) -> int: ... ``` ## Default Value 0 ## Remarks This property holds the current record length set by changerecordlength. When this value is a positive number, the class will accumulate data until [recordlength](#SSHServerpRecordLength) is reached and only then will it fire the onsshchanneldatain event with the data of length [recordlength](#SSHServerpRecordLength). 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 onsshchanneldatain event. A value of *0* (default) means this setting is not used. The *ssh_channel_id* parameter specifies the index of the item in the array. The size of the array is controlled by the [ssh_channel_count](#ssh_channel_count-property) property. This property is read-only. # service property This property holds the channel type that was requested when opening the channel. ## Syntax ```text def get_service(ssh_channel_id: int) -> str: ... ``` ## Default Value "" ## Remarks This property holds the channel type that was requested when opening the channel. For instance "session" or "forwarded-tcpip". The *ssh_channel_id* parameter specifies the index of the item in the array. The size of the array is controlled by the [ssh_channel_count](#ssh_channel_count-property) property. This property is read-only. # ssh_connection_count property The number of records in the SSHConnection arrays. ## Syntax ```text def get_ssh_connection_count() -> int: ... ssh_connection_count = property(get_ssh_connection_count, None) ``` ## Default Value 0 ## Remarks This property controls the size of the following arrays: - [ssh_connection_connected](#ssh_connection_connected-property) - [ssh_connection_local_address](#ssh_connection_local_address-property) - [ssh_connection_remote_host](#ssh_connection_remote_host-property) - [ssh_connection_remote_port](#ssh_connection_remote_port-property) - [ssh_connection_timeout](#ssh_connection_timeout-property) The array indices start at *0* and end at *ssh_connection_count - 1*. This property is read-only. # ssh_connection_connected property This property indicates the status of individual connections. ## Syntax ```text def get_ssh_connection_connected(connection_id: int) -> bool: ... ``` ## Default Value FALSE ## Remarks This property indicates the status of individual connections. When *True*, the connection is established. Use the disconnect method to disconnect an existing connection. The *connection_id* parameter specifies the index of the item in the array. The size of the array is controlled by the [ssh_connection_count](#ssh_connection_count-property) property. This property is read-only. # ssh_connection_local_address property This property shows the IP address of the interface through which the connection is passing. ## Syntax ```text def get_ssh_connection_local_address(connection_id: int) -> str: ... ``` ## Default Value "" ## Remarks This property shows the IP address of the interface through which the connection is passing. [localaddress](#SSHServerpLocalAddress) is important for multihomed hosts in cases in which it can be used to identify the particular network interface an individual connection is going through. The *connection_id* parameter specifies the index of the item in the array. The size of the array is controlled by the [ssh_connection_count](#ssh_connection_count-property) property. This property is read-only. # ssh_connection_remote_host property The RemoteHost shows the IP address of the remote host through which the connection is coming. ## Syntax ```text def get_ssh_connection_remote_host(connection_id: int) -> str: ... ``` ## Default Value "" ## Remarks The [remotehost](#SSHServerpRemoteHost) shows the IP address of the remote host through which the connection is coming. The connection must be valid or an error will be fired. If the class is configured to use a *SOCKS* firewall, the value assigned to this property may be preceded with an "*". If this is the case, the host name is passed to the firewall unresolved and the firewall performs the DNS resolution. The *connection_id* parameter specifies the index of the item in the array. The size of the array is controlled by the [ssh_connection_count](#ssh_connection_count-property) property. This property is read-only. # ssh_connection_remote_port property The RemotePort shows the Transmission Control Protocol (TCP) port on the remote host through which the connection is coming. ## Syntax ```text def get_ssh_connection_remote_port(connection_id: int) -> int: ... ``` ## Default Value 0 ## Remarks The [remoteport](#SSHServerpRemotePort) shows the Transmission Control Protocol (TCP) port on the remote host through which the connection is coming. The connection must be valid or an error will be fired. The *connection_id* parameter specifies the index of the item in the array. The size of the array is controlled by the [ssh_connection_count](#ssh_connection_count-property) property. This property is read-only. # ssh_connection_timeout property This property contains a timeout for the class. ## Syntax ```text def get_ssh_connection_timeout(connection_id: int) -> int: ... def set_ssh_connection_timeout(connection_id: int, value: int) -> None: ... ``` ## Default Value 0 ## Remarks This property contains a timeout for the class. If the timeout property is set to 0, all operations return immediately, potentially failing with an *'WOULDBLOCK'* error if data cannot be sent or received immediately. If timeout is set to a positive value, the class will automatically retry each operation that otherwise would result in a *'WOULDBLOCK'* error for a maximum of timeout seconds. 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 fails with an error. 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 0 (asynchronous operation). The *connection_id* parameter specifies the index of the item in the array. The size of the array is controlled by the [ssh_connection_count](#ssh_connection_count-property) property. # connection_backlog property This property includes the maximum number of pending connections maintained by the Transmission Control Protocol (TCP)/IP subsystem. ## Syntax ```text def get_connection_backlog() -> int: ... def set_connection_backlog(value: int) -> None: ... connection_backlog = property(get_connection_backlog, set_connection_backlog) ``` ## Default Value 5 ## Remarks This property contains the maximum number of pending connections maintained by the TCP/IP subsystem. This value reflects the SOMAXCONN option for the main listening socket. The default value for most systems is 5. You may set this property to a larger value if the server is expected to receive a large number of connections, and queuing them is desirable. # default_auth_methods property The supported authentication methods. ## Syntax ```text def get_default_auth_methods() -> str: ... def set_default_auth_methods(value: str) -> None: ... default_auth_methods = property(get_default_auth_methods, set_default_auth_methods) ``` ## Default Value "password,publickey" ## Remarks This property specifies the supported authentication methods. The client will choose one of the supported mechanisms when authenticating to the class. This must be a comma-separated list of values. For more information on authenticating clients, see the [on_ssh_user_auth_request](#on_ssh_user_auth_request-event) event. The following is a list of methods implemented by the class: | | | | --- | --- | | none | This authentication method is used by most Secure Shell (SSH) clients to obtain the list of authentication methods available for the user's account. In most cases, you should not accept a request using this authentication method. | | password | AuthParam will contain the user-supplied password. If the password is correct, set Accept to True. | | publickey | AuthParam will contain an SSH2 public key blob. If the user's public key is acceptable, set Accept or PartialSuccess to True. The class will then handle verifying the digital signature and will respond to the client accordingly. | | keyboard-interactive | [on_ssh_user_auth_request](#on_ssh_user_auth_request-event) will fire multiple times for keyboard-interactive authentication: It will fire once for each response sent by the client in the SSH_MSG_USERAUTH_INFO_RESPONSE packet (one time for each prompt specified by the daemon). The index of each response will be specified as a suffix in AuthMethod, with AuthParam containing the response to the corresponding prompt (e.g., keyboard-interactive-1, keyboard-interactive-2, and so on). Finally, [on_ssh_user_auth_request](#on_ssh_user_auth_request-event) will fire one last time with AuthMethod set to "keyboard-interactive" and AuthParam set to an empty string. The daemon must set Accept to True every time to allow the authentication process to succeed. | # default_idle_timeout property This property includes the default idle timeout for inactive clients. ## Syntax ```text def get_default_idle_timeout() -> int: ... def set_default_idle_timeout(value: int) -> None: ... default_idle_timeout = property(get_default_idle_timeout, set_default_idle_timeout) ``` ## Default Value 0 ## Remarks This property specifies the idle timeout (in seconds) for clients. When set to a positive value, the class will disconnect idle clients after the specified timeout. This applies only to clients that have not sent or received data within default_idle_timeout seconds. If set to 0 (default), no idle timeout is applied. NOTE: [do_events](#do_events-method) must be called for the class to check existing connections. # default_timeout property The initial timeout value to be used by incoming connections. ## Syntax ```text def get_default_timeout() -> int: ... def set_default_timeout(value: int) -> None: ... default_timeout = property(get_default_timeout, set_default_timeout) ``` ## Default Value 60 ## Remarks This property is used by the class to set the operational timeout value of all inbound connections once they are established. If the timeout is set to 0, all inbound connections will behave asynchronously. The default value is 60, meaning the class will behave synchronously. # keyboard_interactive_message property The instructions to send to the client during keyboard-interactive authentication. ## Syntax ```text def get_keyboard_interactive_message() -> str: ... def set_keyboard_interactive_message(value: str) -> None: ... keyboard_interactive_message = property(get_keyboard_interactive_message, set_keyboard_interactive_message) ``` ## Default Value "" ## Remarks This property should be set to the main instructions to send to the client during keyboard-interactive authentication. # keyboard_interactive_prompt_count property The number of records in the KeyboardInteractivePrompt arrays. ## Syntax ```text def get_keyboard_interactive_prompt_count() -> int: ... def set_keyboard_interactive_prompt_count(value: int) -> None: ... keyboard_interactive_prompt_count = property(get_keyboard_interactive_prompt_count, set_keyboard_interactive_prompt_count) ``` ## Default Value 0 ## Remarks This property controls the size of the following arrays: - [keyboard_interactive_prompt_echo](#keyboard_interactive_prompt_echo-property) - [keyboard_interactive_prompt_prompt](#keyboard_interactive_prompt_prompt-property) The array indices start at *0* and end at *keyboard_interactive_prompt_count - 1*. # keyboard_interactive_prompt_echo property This property specifies whether or not the client should echo the value entered by the user. ## Syntax ```text def get_keyboard_interactive_prompt_echo(prompt_index: int) -> bool: ... def set_keyboard_interactive_prompt_echo(prompt_index: int, value: bool) -> None: ... ``` ## Default Value FALSE ## Remarks This property specifies whether or not the client should echo the value entered by the user. The *prompt_index* parameter specifies the index of the item in the array. The size of the array is controlled by the [keyboard_interactive_prompt_count](#keyboard_interactive_prompt_count-property) property. # keyboard_interactive_prompt_prompt property This property contains the prompt label or text the client should present to the user. ## Syntax ```text def get_keyboard_interactive_prompt_prompt(prompt_index: int) -> str: ... def set_keyboard_interactive_prompt_prompt(prompt_index: int, value: str) -> None: ... ``` ## Default Value "" ## Remarks This property contains the prompt label or text the client should present to the user. The *prompt_index* parameter specifies the index of the item in the array. The size of the array is controlled by the [keyboard_interactive_prompt_count](#keyboard_interactive_prompt_count-property) property. # listening property This property indicates whether the class is listening for incoming connections on LocalPort. ## Syntax ```text def get_listening() -> bool: ... listening = property(get_listening, None) ``` ## Default Value FALSE ## Remarks This property indicates whether the class is listening for connections on the port specified by the [local_port](#local_port-property) property. Use the [start_listening](#start_listening-method) and [stop_listening](#stop_listening-method) methods to control whether the class is listening. This property is read-only. # local_host property The name of the local host or user-assigned IP interface through which connections are initiated or accepted. ## Syntax ```text def get_local_host() -> str: ... def set_local_host(value: str) -> None: ... local_host = property(get_local_host, set_local_host) ``` ## 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 classes) 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 local_host 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: local_host is not persistent. You must always set it in code, and never in the property window. # local_port property The Transmission Control Protocol (TCP) port in the local host where the class listens. ## Syntax ```text def get_local_port() -> int: ... def set_local_port(value: int) -> None: ... local_port = property(get_local_port, set_local_port) ``` ## Default Value 22 ## Remarks The local_port property must be set before TCPServer starts listening. If its value is 0, then the TCP/IP subsystem picks a port number at random. The port number can be found by checking the value of the local_port property after TCPServer is in listening mode (after successfully assigning True to the [listening](#listening-property) property). NOTE: The service port is not shared among servers (i.e., only one TCPServer can be 'listening' on a particular port at one time). # ssh_cert_count property The number of records in the SSHCert arrays. ## Syntax ```text def get_ssh_cert_count() -> int: ... def set_ssh_cert_count(value: int) -> None: ... ssh_cert_count = property(get_ssh_cert_count, set_ssh_cert_count) ``` ## Default Value 0 ## Remarks This property controls the size of the following arrays: - [ssh_cert_effective_date](#ssh_cert_effective_date-property) - [ssh_cert_encoded](#ssh_cert_encoded-property) - [ssh_cert_expiration_date](#ssh_cert_expiration_date-property) - [ssh_cert_extended_key_usage](#ssh_cert_extended_key_usage-property) - [ssh_cert_fingerprint](#ssh_cert_fingerprint-property) - [ssh_cert_fingerprint_sha1](#ssh_cert_fingerprint_sha1-property) - [ssh_cert_fingerprint_sha256](#ssh_cert_fingerprint_sha256-property) - [ssh_cert_issuer](#ssh_cert_issuer-property) - [ssh_cert_private_key](#ssh_cert_private_key-property) - [ssh_cert_private_key_available](#ssh_cert_private_key_available-property) - [ssh_cert_private_key_container](#ssh_cert_private_key_container-property) - [ssh_cert_public_key](#ssh_cert_public_key-property) - [ssh_cert_public_key_algorithm](#ssh_cert_public_key_algorithm-property) - [ssh_cert_public_key_length](#ssh_cert_public_key_length-property) - [ssh_cert_serial_number](#ssh_cert_serial_number-property) - [ssh_cert_signature_algorithm](#ssh_cert_signature_algorithm-property) - [ssh_cert_store](#ssh_cert_store-property) - [ssh_cert_store_password](#ssh_cert_store_password-property) - [ssh_cert_store_type](#ssh_cert_store_type-property) - [ssh_cert_subject](#ssh_cert_subject-property) - [ssh_cert_subject_alt_names](#ssh_cert_subject_alt_names-property) - [ssh_cert_thumbprint_md5](#ssh_cert_thumbprint_md5-property) - [ssh_cert_thumbprint_sha1](#ssh_cert_thumbprint_sha1-property) - [ssh_cert_thumbprint_sha256](#ssh_cert_thumbprint_sha256-property) - [ssh_cert_usage](#ssh_cert_usage-property) - [ssh_cert_usage_flags](#ssh_cert_usage_flags-property) - [ssh_cert_version](#ssh_cert_version-property) The array indices start at *0* and end at *ssh_cert_count - 1*. # ssh_cert_effective_date property The date on which this certificate becomes valid. ## Syntax ```text def get_ssh_cert_effective_date(ssh_cert_index: int) -> str: ... ``` ## Default Value "" ## Remarks 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. The *ssh_cert_index* parameter specifies the index of the item in the array. The size of the array is controlled by the [ssh_cert_count](#ssh_cert_count-property) property. This property is read-only. # ssh_cert_encoded property The certificate (PEM/Base64 encoded). ## Syntax ```text def get_ssh_cert_encoded(ssh_cert_index: int) -> bytes: ... def set_ssh_cert_encoded(ssh_cert_index: int, value: bytes) -> None: ... ``` ## Default Value "" ## Remarks The certificate (PEM/Base64 encoded). This property is used to assign a specific certificate. The [store](#SSHServerpStore) and [subject](#SSHServerpSubject) properties also may be used to specify a certificate. When [encoded](#SSHServerpEncoded) is set, a search is initiated in the current [store](#SSHServerpStore) for the private key of the certificate. If the key is found, [subject](#SSHServerpSubject) is updated to reflect the full subject of the selected certificate; otherwise, [subject](#SSHServerpSubject) is set to an empty string. The *ssh_cert_index* parameter specifies the index of the item in the array. The size of the array is controlled by the [ssh_cert_count](#ssh_cert_count-property) property. # ssh_cert_expiration_date property The date on which the certificate expires. ## Syntax ```text def get_ssh_cert_expiration_date(ssh_cert_index: int) -> str: ... ``` ## Default Value "" ## Remarks 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. The *ssh_cert_index* parameter specifies the index of the item in the array. The size of the array is controlled by the [ssh_cert_count](#ssh_cert_count-property) property. This property is read-only. # ssh_cert_extended_key_usage property A comma-delimited list of extended key usage identifiers. ## Syntax ```text def get_ssh_cert_extended_key_usage(ssh_cert_index: int) -> str: ... ``` ## Default Value "" ## Remarks A comma-delimited list of extended key usage identifiers. These are the same as ASN.1 object identifiers (OIDs). The *ssh_cert_index* parameter specifies the index of the item in the array. The size of the array is controlled by the [ssh_cert_count](#ssh_cert_count-property) property. This property is read-only. # ssh_cert_fingerprint property The hex-encoded, 16-byte MD5 fingerprint of the certificate. ## Syntax ```text def get_ssh_cert_fingerprint(ssh_cert_index: int) -> str: ... ``` ## Default Value "" ## Remarks 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* The *ssh_cert_index* parameter specifies the index of the item in the array. The size of the array is controlled by the [ssh_cert_count](#ssh_cert_count-property) property. This property is read-only. # ssh_cert_fingerprint_sha1 property The hex-encoded, 20-byte SHA-1 fingerprint of the certificate. ## Syntax ```text def get_ssh_cert_fingerprint_sha1(ssh_cert_index: int) -> str: ... ``` ## Default Value "" ## Remarks 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* The *ssh_cert_index* parameter specifies the index of the item in the array. The size of the array is controlled by the [ssh_cert_count](#ssh_cert_count-property) property. This property is read-only. # ssh_cert_fingerprint_sha256 property The hex-encoded, 32-byte SHA-256 fingerprint of the certificate. ## Syntax ```text def get_ssh_cert_fingerprint_sha256(ssh_cert_index: int) -> str: ... ``` ## Default Value "" ## Remarks 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* The *ssh_cert_index* parameter specifies the index of the item in the array. The size of the array is controlled by the [ssh_cert_count](#ssh_cert_count-property) property. This property is read-only. # ssh_cert_issuer property The issuer of the certificate. ## Syntax ```text def get_ssh_cert_issuer(ssh_cert_index: int) -> str: ... ``` ## Default Value "" ## Remarks The issuer of the certificate. This property contains a string representation of the name of the issuing authority for the certificate. The *ssh_cert_index* parameter specifies the index of the item in the array. The size of the array is controlled by the [ssh_cert_count](#ssh_cert_count-property) property. This property is read-only. # ssh_cert_private_key property The private key of the certificate (if available). ## Syntax ```text def get_ssh_cert_private_key(ssh_cert_index: int) -> str: ... ``` ## Default Value "" ## Remarks The private key of the certificate (if available). The key is provided as PEM/Base64-encoded data. NOTE: The [privatekey](#SSHServerpPrivateKey) may be available but not exportable. In this case, [privatekey](#SSHServerpPrivateKey) returns an empty string. The *ssh_cert_index* parameter specifies the index of the item in the array. The size of the array is controlled by the [ssh_cert_count](#ssh_cert_count-property) property. This property is read-only. # ssh_cert_private_key_available property Whether a PrivateKey is available for the selected certificate. ## Syntax ```text def get_ssh_cert_private_key_available(ssh_cert_index: int) -> bool: ... ``` ## Default Value FALSE ## Remarks Whether a [privatekey](#SSHServerpPrivateKey) is available for the selected certificate. If [privatekeyavailable](#SSHServerpPrivateKeyAvailable) is True, the certificate may be used for authentication purposes (e.g., server authentication). The *ssh_cert_index* parameter specifies the index of the item in the array. The size of the array is controlled by the [ssh_cert_count](#ssh_cert_count-property) property. This property is read-only. # ssh_cert_private_key_container property The name of the PrivateKey container for the certificate (if available). ## Syntax ```text def get_ssh_cert_private_key_container(ssh_cert_index: int) -> str: ... ``` ## Default Value "" ## Remarks The name of the [privatekey](#SSHServerpPrivateKey) container for the certificate (if available). This functionality is available only on Windows platforms. The *ssh_cert_index* parameter specifies the index of the item in the array. The size of the array is controlled by the [ssh_cert_count](#ssh_cert_count-property) property. This property is read-only. # ssh_cert_public_key property The public key of the certificate. ## Syntax ```text def get_ssh_cert_public_key(ssh_cert_index: int) -> str: ... ``` ## Default Value "" ## Remarks The public key of the certificate. The key is provided as PEM/Base64-encoded data. The *ssh_cert_index* parameter specifies the index of the item in the array. The size of the array is controlled by the [ssh_cert_count](#ssh_cert_count-property) property. This property is read-only. # ssh_cert_public_key_algorithm property The textual description of the certificate's public key algorithm. ## Syntax ```text def get_ssh_cert_public_key_algorithm(ssh_cert_index: int) -> str: ... ``` ## Default Value "" ## Remarks The textual description of the certificate's public key algorithm. The property contains either the name of the algorithm (e.g., "RSA" or "RSADH") or an object identifier (OID) string representing the algorithm. The *ssh_cert_index* parameter specifies the index of the item in the array. The size of the array is controlled by the [ssh_cert_count](#ssh_cert_count-property) property. This property is read-only. # ssh_cert_public_key_length property The length of the certificate's public key (in bits). ## Syntax ```text def get_ssh_cert_public_key_length(ssh_cert_index: int) -> int: ... ``` ## Default Value 0 ## Remarks The length of the certificate's public key (in bits). Common values are 512, 1024, and 2048. The *ssh_cert_index* parameter specifies the index of the item in the array. The size of the array is controlled by the [ssh_cert_count](#ssh_cert_count-property) property. This property is read-only. # ssh_cert_serial_number property The serial number of the certificate encoded as a string. ## Syntax ```text def get_ssh_cert_serial_number(ssh_cert_index: int) -> str: ... ``` ## Default Value "" ## Remarks 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. The *ssh_cert_index* parameter specifies the index of the item in the array. The size of the array is controlled by the [ssh_cert_count](#ssh_cert_count-property) property. This property is read-only. # ssh_cert_signature_algorithm property The text description of the certificate's signature algorithm. ## Syntax ```text def get_ssh_cert_signature_algorithm(ssh_cert_index: int) -> str: ... ``` ## Default Value "" ## Remarks The text description of the certificate's signature algorithm. The property contains either the name of the algorithm (e.g., "RSA" or "RSAMD5RSA") or an object identifier (OID) string representing the algorithm. The *ssh_cert_index* parameter specifies the index of the item in the array. The size of the array is controlled by the [ssh_cert_count](#ssh_cert_count-property) property. This property is read-only. # ssh_cert_store property The name of the certificate store for the client certificate. ## Syntax ```text def get_ssh_cert_store(ssh_cert_index: int) -> bytes: ... def set_ssh_cert_store(ssh_cert_index: int, value: bytes) -> None: ... ``` ## Default Value "MY" ## Remarks The name of the certificate store for the client certificate. The [storetype](#SSHServerpStoreType) property denotes the type of the certificate store specified by [store](#SSHServerpStore). If the store is password-protected, specify the password in [storepassword](#SSHServerpStorePassword). [store](#SSHServerpStore) is used in conjunction with the [subject](#SSHServerpSubject) property to specify client certificates. If [store](#SSHServerpStore) has a value, and [subject](#SSHServerpSubject) or [encoded](#SSHServerpEncoded) is set, a search for a certificate is initiated. Please see the [subject](#SSHServerpSubject) property 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. | 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). The *ssh_cert_index* parameter specifies the index of the item in the array. The size of the array is controlled by the [ssh_cert_count](#ssh_cert_count-property) property. # ssh_cert_store_password property If the type of certificate store requires a password, this property is used to specify the password needed to open the certificate store. ## Syntax ```text def get_ssh_cert_store_password(ssh_cert_index: int) -> str: ... def set_ssh_cert_store_password(ssh_cert_index: int, value: str) -> None: ... ``` ## Default Value "" ## Remarks If the type of certificate store requires a password, this property is used to specify the password needed to open the certificate store. The *ssh_cert_index* parameter specifies the index of the item in the array. The size of the array is controlled by the [ssh_cert_count](#ssh_cert_count-property) property. # ssh_cert_store_type property The type of certificate store for this certificate. ## Syntax ```text def get_ssh_cert_store_type(ssh_cert_index: int) -> int: ... def set_ssh_cert_store_type(ssh_cert_index: int, value: int) -> None: ... ``` ## Possible Values ```text 0 # User1 # Machine2 # PFXFile3 # PFXBlob4 # JKSFile5 # JKSBlob6 # PEMKeyFile7 # PEMKeyBlob8 # PublicKeyFile9 # PublicKeyBlob10 # SSHPublicKeyBlob11 # P7BFile12 # P7BBlob13 # SSHPublicKeyFile14 # PPKFile15 # PPKBlob16 # XMLFile17 # XMLBlob18 # JWKFile19 # JWKBlob20 # SecurityKey21 # BCFKSFile22 # BCFKSBlob23 # PKCS1199 # Auto ``` ## Default Value 0 ## Remarks 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 property can take one of the following values: ```csharp sftp.SSHCert = new Certificate(CertStoreTypes.cstPKCS11, @"C:\Program Files\OpenSC Project\OpenSC\pkcs11\opensc-pkcs11.dll", "123456", // PIN "CN=certsubject"); sftp.SSHUser = "test"; sftp.SSHLogon("myhost", 22); ``` ```csharp 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); ``` | | | | --- | --- | | 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, create a new [Certificate](#TypeCertificate) object and pass cstPKCS11 as the [storetype](#SSHServerpStoreType), the full path of the PKCS#11 DLL as the [store](#SSHServerpStore), and the PIN as the [storepassword](#SSHServerpStorePassword). Code Example. SSH Authentication with Security Key (without CertMgr): Alternatively, collect the necessary data using the [CertMgr](#CertMgr) class by calling the [liststorecertificates](#CertMgrmListStoreCertificates) method after setting the corresponding properties accordingly. The certificate information returned in the [oncertlist](#CertMgreCertList) event's CertEncoded parameter may be saved for later use. When using a certificate obtained with this approach, pass the previously saved security key information as the [store](#SSHServerpStore) and set [storepassword](#SSHServerpStorePassword) to the PIN. Code Example. SSH Authentication with Security Key (with CertMgr): | | 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. | The *ssh_cert_index* parameter specifies the index of the item in the array. The size of the array is controlled by the [ssh_cert_count](#ssh_cert_count-property) property. # ssh_cert_subject property The subject of the certificate used for client authentication. ## Syntax ```text def get_ssh_cert_subject(ssh_cert_index: int) -> str: ... def set_ssh_cert_subject(ssh_cert_index: int, value: str) -> None: ... ``` ## Default Value "" ## Remarks The subject of the certificate used for client authentication. This property must be set after all other certificate properties are set. When this property is set, a search is performed in the current certificate store to locate a certificate with a matching subject. If a matching certificate is found, the property is set to the full subject of the matching certificate. 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=example@email.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. The *ssh_cert_index* parameter specifies the index of the item in the array. The size of the array is controlled by the [ssh_cert_count](#ssh_cert_count-property) property. # ssh_cert_subject_alt_names property Comma-separated lists of alternative subject names for the certificate. ## Syntax ```text def get_ssh_cert_subject_alt_names(ssh_cert_index: int) -> str: ... ``` ## Default Value "" ## Remarks Comma-separated lists of alternative subject names for the certificate. The *ssh_cert_index* parameter specifies the index of the item in the array. The size of the array is controlled by the [ssh_cert_count](#ssh_cert_count-property) property. This property is read-only. # ssh_cert_thumbprint_md5 property The MD5 hash of the certificate. ## Syntax ```text def get_ssh_cert_thumbprint_md5(ssh_cert_index: int) -> str: ... ``` ## Default Value "" ## Remarks 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. The *ssh_cert_index* parameter specifies the index of the item in the array. The size of the array is controlled by the [ssh_cert_count](#ssh_cert_count-property) property. This property is read-only. # ssh_cert_thumbprint_sha1 property The SHA-1 hash of the certificate. ## Syntax ```text def get_ssh_cert_thumbprint_sha1(ssh_cert_index: int) -> str: ... ``` ## Default Value "" ## Remarks 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. The *ssh_cert_index* parameter specifies the index of the item in the array. The size of the array is controlled by the [ssh_cert_count](#ssh_cert_count-property) property. This property is read-only. # ssh_cert_thumbprint_sha256 property The SHA-256 hash of the certificate. ## Syntax ```text def get_ssh_cert_thumbprint_sha256(ssh_cert_index: int) -> str: ... ``` ## Default Value "" ## Remarks 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. The *ssh_cert_index* parameter specifies the index of the item in the array. The size of the array is controlled by the [ssh_cert_count](#ssh_cert_count-property) property. This property is read-only. # ssh_cert_usage property The text description of UsageFlags . ## Syntax ```text def get_ssh_cert_usage(ssh_cert_index: int) -> str: ... ``` ## Default Value "" ## Remarks The text description of [usageflags](#SSHServerpUsageFlags). 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. The *ssh_cert_index* parameter specifies the index of the item in the array. The size of the array is controlled by the [ssh_cert_count](#ssh_cert_count-property) property. This property is read-only. # ssh_cert_usage_flags property The flags that show intended use for the certificate. ## Syntax ```text def get_ssh_cert_usage_flags(ssh_cert_index: int) -> int: ... ``` ## Default Value 0 ## Remarks The flags that show intended use for the certificate. The value of [usageflags](#SSHServerpUsageFlags) 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](#SSHServerpUsage) property for a text representation of [usageflags](#SSHServerpUsageFlags). This functionality currently is not available when the provider is OpenSSL. The *ssh_cert_index* parameter specifies the index of the item in the array. The size of the array is controlled by the [ssh_cert_count](#ssh_cert_count-property) property. This property is read-only. # ssh_cert_version property The certificate's version number. ## Syntax ```text def get_ssh_cert_version(ssh_cert_index: int) -> str: ... ``` ## Default Value "" ## Remarks The certificate's version number. The possible values are the strings "V1", "V2", and "V3". The *ssh_cert_index* parameter specifies the index of the item in the array. The size of the array is controlled by the [ssh_cert_count](#ssh_cert_count-property) property. This property is read-only. # ssh_compression_algorithms property The comma-separated list containing all allowable compression algorithms. ## Syntax ```text def get_ssh_compression_algorithms() -> str: ... def set_ssh_compression_algorithms(value: str) -> None: ... ssh_compression_algorithms = property(get_ssh_compression_algorithms, set_ssh_compression_algorithms) ``` ## 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 # ssh_encryption_algorithms property The comma-separated list containing all allowable encryption algorithms. ## Syntax ```text def get_ssh_encryption_algorithms() -> str: ... def set_ssh_encryption_algorithms(value: str) -> None: ... ssh_encryption_algorithms = property(get_ssh_encryption_algorithms, set_ssh_encryption_algorithms) ``` ## Default Value "aes256-ctr,aes192-ctr,aes128-ctr,3des-ctr,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 - aes256-cbc - aes192-ctr - aes192-cbc - aes128-ctr - aes128-cbc - 3des-ctr - 3des-cbc - cast128-cbc - blowfish-cbc - arcfour - arcfour128 - arcfour256 - aes256-gcm@openssh.com - aes128-gcm@openssh.com - chacha20-poly1305@openssh.com # change_record_length method Changes the length of received data records. ## Syntax ```text def change_record_length(channel_id: int, record_length: int) -> None: ... ``` ## 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 is received and only then will it fire the [on_ssh_channel_data_in](#on_ssh_channel_data_in-event) event 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 on_data_in event. A value of 0 (default) means this functionality is not used. # close_channel method Closes an existing SSHChannel . ## Syntax ```text def close_channel(channel_id: int) -> None: ... ``` ## Remarks *ChannelId* is the identifier for the Secure Shell (SSH) channel to be closed. # config method Sets or retrieves a configuration setting. ## Syntax ```text def config(configuration_string: str) -> str: ... ``` ## Remarks config is a generic method available in every class. It is used to set and retrieve [configuration settings](#sshserver-config-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](#sshserver-config-settings), you must call *Config("PROPERTY")*. The value will be returned as a string. # disconnect method This method disconnects the specified client. ## Syntax ```text def disconnect(connection_id: int) -> None: ... ``` ## Remarks Calling this method will disconnect the client specified by the *connection_id* parameter. # do_events method This method processes events from the internal message queue. ## Syntax ```text def do_events() -> None: ... ``` ## Remarks When do_events is called, the class processes any available events. If no events are available, it waits for a preset period of time, and then returns. # exchange_keys method Causes the class to exchange a new set of session keys on the specified connection. ## Syntax ```text def exchange_keys(connection_id: int) -> None: ... ``` ## Remarks Secure Shell (SSH) key renegotiation can be initiated by either end of an established SSH connection. exchange_keys allows the server to start such a renegotiation with the client. During this process, [on_ssh_status](#on_ssh_status-event) events will fire with updates about 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. This makes it more difficult to break the security of data-intensive or long-lived connections. # get_ssh_param method Reads a field from a Secure Shell (SSH) packet's payload. ## Syntax ```text def get_ssh_param(payload: bytes, field: str) -> str: ... ``` ## 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 [on_ssh_channel_request](#on_ssh_channel_request-event). *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 [set_ssh_param](#set_ssh_param-method). 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 [set_ssh_param](#set_ssh_param-method). # get_ssh_param_bytes method Reads a field from a Secure Shell (SSH) packet's payload. ## Syntax ```text def get_ssh_param_bytes(payload: bytes, field: str) -> bytes: ... ``` ## Remarks This method is the same as calling [get_ssh_param](#get_ssh_param-method), but it returns raw bytes instead of strings. # open_channel method Opens a new SSHChannel . ## Syntax ```text def open_channel(connection_id: int, channel_type: str) -> str: ... ``` ## 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 open_channel, and data can be sent over it with [send_channel_data](#send_channel_data-method). *ChannelType* represents the type of Secure Shell (SSH) channel to be opened. The most common type of channel is "session". If the call to open_channel succeeds, an SSHChannel will be created and added to the channels collection. # reset method This method will reset the class. ## Syntax ```text def reset() -> None: ... ``` ## Remarks This method will reset the class's properties to their default values. # send_bytes method Sends binary data to the specified channel. ## Syntax ```text def send_bytes(channel_id: int, data: bytes) -> None: ... ``` ## Remarks This method sends binary data to the channel identified by *ChannelId*. To send text, use the [send_text](#send_text-method) method instead. # send_channel_data method Sends data over a Secure Shell (SSH) channel. ## Syntax ```text def send_channel_data(channel_id: int, data: bytes) -> None: ... ``` ## Remarks This method can be used to send arbitrary data to the channel with the specified *ChannelId*. # send_ssh_packet method Sends an encoded Secure Shell (SSH) packet to the server. ## Syntax ```text def send_ssh_packet(channel_id: int, packet_type: int, payload: bytes) -> None: ... ``` ## 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 [set_ssh_param](#set_ssh_param-method). When send_ssh_packet is called, the class will finish building the packet, encrypt it for transport, and send it to the server. # send_text method Sends text to the specified channel. ## Syntax ```text def send_text(channel_id: int, text: str) -> None: ... ``` ## Remarks This method sends text to the client identified by *ChannelId*. To send binary data, use the [send_bytes](#send_bytes-method) method instead. # set_ssh_param method Writes a field to the end of a payload. ## Syntax ```text def set_ssh_param(payload: bytes, field_type: str, field_value: str) -> bytes: ... ``` ## Remarks This method is used to build the payload portion of a Secure Shell (SSH) packet to be sent later by a call to [send_ssh_packet](#send_ssh_packet-method). *Payload* should contain the result of a previous call to set_ssh_param. *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. # shutdown method This method shuts down the server. ## Syntax ```text def shutdown() -> None: ... ``` ## Remarks This method shuts down the server. Calling this method is equivalent to calling [stop_listening](#stop_listening-method) and then breaking every client connection by calling [disconnect](#disconnect-method). # start_listening method This method starts listening for incoming connections. ## Syntax ```text def start_listening() -> None: ... ``` ## Remarks This method begins listening for incoming connections on the port specified by [local_port](#local_port-property). Once listening, events will fire as new clients connect and data are transferred. To stop listening for new connections, call [stop_listening](#stop_listening-method). To stop listening for new connections and to disconnect all existing clients, call [shutdown](#shutdown-method). # stop_listening method This method stops listening for new connections. ## Syntax ```text def stop_listening() -> None: ... ``` ## Remarks This method stops listening for new connections. After being called, any new connection attempts will be rejected. Calling this method does not disconnect existing connections. To stop listening and to disconnect all existing clients, call [shutdown](#shutdown-method) instead. # on_connected event Fired immediately after a connection completes (or fails). ## Syntax ```text class SSHServerConnectedEventParams(object): @property def connection_id() -> int: ... @property def status_code() -> int: ... @property def description() -> str: ... @property def cert_store_type() -> int: ... @cert_store_type.setter def cert_store_type(value) -> None: ... @property def cert_store() -> str: ... @cert_store.setter def cert_store(value) -> None: ... @property def cert_password() -> str: ... @cert_password.setter def cert_password(value) -> None: ... @property def cert_subject() -> str: ... @cert_subject.setter def cert_subject(value) -> None: ... # In class SSHServer: @property def on_connected() -> Callable[[SSHServerConnectedEventParams], None]: ... @on_connected.setter def on_connected(event_hook: Callable[[SSHServerConnectedEventParams], None]) -> None: ... ``` ## Remarks If the connection is made normally, *StatusCode* is 0, and *Description* is "OK". If the connection fails, *StatusCode* has the error code returned by the system. *Description* contains a description of this code. The value of *StatusCode* is equal to the value of the system error. Please refer to the [Error Codes](#sshserver-errors) section for more information. *ConnectionId* is the connection Id of the client requesting the connection. *CertStoreType* is the store type of the alternate certificate to use for this connection. 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 property can take one of the following values: ```csharp sftp.SSHCert = new Certificate(CertStoreTypes.cstPKCS11, @"C:\Program Files\OpenSC Project\OpenSC\pkcs11\opensc-pkcs11.dll", "123456", // PIN "CN=cert_subject"); sftp.SSHUser = "test"; sftp.SSHLogon("myhost", 22); ``` ```csharp 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); ``` | | | | --- | --- | | 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, create a new Certificate object and pass cstPKCS11 as the [](#f_StoreType), the full path of the PKCS#11 DLL as the [](#f_Store), and the PIN as the [](#f_StorePassword). Code Example. SSH Authentication with Security Key (without CertMgr): Alternatively, collect the necessary data using the [CertMgr](CertMgr.md#CertMgr) class by calling the [list_store_certificates](CertMgr.md#CertMgr_m_ListStoreCertificates) method after setting the corresponding properties accordingly. The certificate information returned in the [on_cert_list](CertMgr.md#CertMgr_e_CertList) event's CertEncoded parameter may be saved for later use. When using a certificate obtained with this approach, pass the previously saved security key information as the [](#f_Store) and set [](#f_StorePassword) to the PIN. Code Example. SSH Authentication with Security Key (with CertMgr): | | 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. | *CertStore* is the store name or location of the alternate certificate to use for this connection. 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. | 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). *CertPassword* is the password of the certificate store containing the alternate certificate to use for this connection. *CertSubject* is the subject of the alternate certificate to use for this connection. The special value *** matches any subject and will select the first certificate in the 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=example@email.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. # on_connection_request event This event is fired when a request for connection comes from a remote host. ## Syntax ```text class SSHServerConnectionRequestEventParams(object): @property def address() -> str: ... @property def port() -> int: ... @property def accept() -> bool: ... @accept.setter def accept(value) -> None: ... # In class SSHServer: @property def on_connection_request() -> Callable[[SSHServerConnectionRequestEventParams], None]: ... @on_connection_request.setter def on_connection_request(event_hook: Callable[[SSHServerConnectionRequestEventParams], None]) -> None: ... ``` ## Remarks This event indicates an incoming connection. The connection is accepted by default. *address* and *port* will contain information about the remote host requesting the inbound connection. If you want to refuse it, you can set the *accept* parameter to False. # on_disconnected event This event is fired when a connection is closed. ## Syntax ```text class SSHServerDisconnectedEventParams(object): @property def connection_id() -> int: ... @property def status_code() -> int: ... @property def description() -> str: ... # In class SSHServer: @property def on_disconnected() -> Callable[[SSHServerDisconnectedEventParams], None]: ... @on_disconnected.setter def on_disconnected(event_hook: Callable[[SSHServerDisconnectedEventParams], None]) -> None: ... ``` ## Remarks If the connection is broken normally, *status_code* is 0, and *description* is "OK". If the connection is broken for any other reason, *status_code* has the error code returned by the system. *description* contains a description of this code. The value of *status_code* is equal to the value of the system error. Please refer to the [Error Codes](#sshserver-errors) section for more information. # on_error event Fired when errors occur during data delivery. ## Syntax ```text class SSHServerErrorEventParams(object): @property def connection_id() -> int: ... @property def error_code() -> int: ... @property def description() -> str: ... # In class SSHServer: @property def on_error() -> Callable[[SSHServerErrorEventParams], None]: ... @on_error.setter def on_error(event_hook: Callable[[SSHServerErrorEventParams], None]) -> None: ... ``` ## Remarks The on_error event is fired in case of exceptional conditions during message processing. Normally the class fails with an error. *ConnectionId* contains an error code and *Description* contains a textual description of the error. For a list of valid error codes and their descriptions, please refer to the [Error Codes](#sshserver-errors) section. *ErrorCode* contains an error code and *Description* contains a textual description of the error. For a list of valid error codes and their descriptions, please refer to the [Error Codes](#sshserver-errors) section. # on_log event Fired once for each log message. ## Syntax ```text class SSHServerLogEventParams(object): @property def connection_id() -> int: ... @property def log_level() -> int: ... @property def message() -> str: ... @property def log_type() -> str: ... # In class SSHServer: @property def on_log() -> Callable[[SSHServerLogEventParams], None]: ... @on_log.setter def on_log(event_hook: Callable[[SSHServerLogEventParams], None]) -> None: ... ``` ## Remarks Fired once for each log message generated by the class. The verbosity is controlled by the [LogLevel](#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. *ConnectionId* specifies the connection to which the log message is applicable. # on_ssh_channel_closed event Fired when a channel is closed. ## Syntax ```text class SSHServerSSHChannelClosedEventParams(object): @property def connection_id() -> int: ... @property def channel_id() -> int: ... # In class SSHServer: @property def on_ssh_channel_closed() -> Callable[[SSHServerSSHChannelClosedEventParams], None]: ... @on_ssh_channel_closed.setter def on_ssh_channel_closed(event_hook: Callable[[SSHServerSSHChannelClosedEventParams], None]) -> None: ... ``` ## Remarks The on_ssh_channel_closed event is fired when a channel is closed on a Secure Shell (SSH) connection. *ConnectionId* identifies the connection. *ChannelId* identifies the channel. 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. # on_ssh_channel_data_in event Fired when data are received on a Secure Shell (SSH) channel. ## Syntax ```text class SSHServerSSHChannelDataInEventParams(object): @property def connection_id() -> int: ... @property def channel_id() -> int: ... @property def data() -> bytes: ... # In class SSHServer: @property def on_ssh_channel_data_in() -> Callable[[SSHServerSSHChannelDataInEventParams], None]: ... @on_ssh_channel_data_in.setter def on_ssh_channel_data_in(event_hook: Callable[[SSHServerSSHChannelDataInEventParams], None]) -> None: ... ``` ## Remarks Whenever a client sends data to an SSH channel, the on_ssh_channel_data_in event will fire. *ChannelId* will identify the channel receiving data. *Data* will contain the raw data being received. *ConnectionId* identifies the connection. *ChannelId* identifies the channel. 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. # on_ssh_channel_eof event Fired when the remote peer signals the end of the data stream for the channel. ## Syntax ```text class SSHServerSSHChannelEOFEventParams(object): @property def connection_id() -> int: ... @property def channel_id() -> int: ... # In class SSHServer: @property def on_ssh_channel_eof() -> Callable[[SSHServerSSHChannelEOFEventParams], None]: ... @on_ssh_channel_eof.setter def on_ssh_channel_eof(event_hook: Callable[[SSHServerSSHChannelEOFEventParams], None]) -> None: ... ``` ## Remarks The on_ssh_channel_eof event is fired when the end of the data stream for a channel on a Secure Shell (SSH) connection is reached. *ConnectionId* identifies the connection. *ChannelId* identifies the channel. 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. # on_ssh_channel_opened event Fired when a channel is successfully opened. ## Syntax ```text class SSHServerSSHChannelOpenedEventParams(object): @property def connection_id() -> int: ... @property def channel_id() -> int: ... # In class SSHServer: @property def on_ssh_channel_opened() -> Callable[[SSHServerSSHChannelOpenedEventParams], None]: ... @on_ssh_channel_opened.setter def on_ssh_channel_opened(event_hook: Callable[[SSHServerSSHChannelOpenedEventParams], None]) -> None: ... ``` ## Remarks The on_ssh_channel_opened event is fired when a channel is successfully opened on a Secure Shell (SSH) connection. *ConnectionId* identifies the connection. *ChannelId* identifies the channel. 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. # on_ssh_channel_open_request event Fired when a client attempts to open a new channel. ## Syntax ```text class SSHServerSSHChannelOpenRequestEventParams(object): @property def connection_id() -> int: ... @property def channel_id() -> int: ... @property def service() -> str: ... @property def parameters() -> bytes: ... @property def accept() -> bool: ... @accept.setter def accept(value) -> None: ... # In class SSHServer: @property def on_ssh_channel_open_request() -> Callable[[SSHServerSSHChannelOpenRequestEventParams], None]: ... @on_ssh_channel_open_request.setter def on_ssh_channel_open_request(event_hook: Callable[[SSHServerSSHChannelOpenRequestEventParams], None]) -> None: ... ``` ## Remarks This event is fired whenever a client attempts to open a new channel for a given connection. *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"). *Accept* must to be set to True to accept the channel open request. *ConnectionId* identifies the connection. *ChannelId* identifies the channel. If the channel open request contains extra information, it will be contained in *Parameters*; you can extract data from it using [get_ssh_param](#get_ssh_param-method) and [get_ssh_param_bytes](#get_ssh_param_bytes-method). 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). 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. # on_ssh_channel_ready_to_send event Fired when the class is ready to send data. ## Syntax ```text class SSHServerSSHChannelReadyToSendEventParams(object): @property def connection_id() -> int: ... @property def channel_id() -> int: ... # In class SSHServer: @property def on_ssh_channel_ready_to_send() -> Callable[[SSHServerSSHChannelReadyToSendEventParams], None]: ... @on_ssh_channel_ready_to_send.setter def on_ssh_channel_ready_to_send(event_hook: Callable[[SSHServerSSHChannelReadyToSendEventParams], None]) -> None: ... ``` ## Remarks This event fires when data can be sent over the Secure Shell (SSH) channel specified by *ChannelId* for the connection specified by *ConnectionId*. When a channel is opened, this event will fire once 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 on_ssh_channel_ready_to_send or [ready_to_send](#ready_to_send-property) 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 on_ssh_channel_ready_to_send and [ready_to_send](#ready_to_send-property) do not need to be monitored. # on_ssh_channel_request event Fired when the client sends a channel request to the SSHHost . ## Syntax ```text class SSHServerSSHChannelRequestEventParams(object): @property def connection_id() -> int: ... @property def channel_id() -> int: ... @property def request_type() -> str: ... @property def packet() -> bytes: ... @property def success() -> bool: ... @success.setter def success(value) -> None: ... # In class SSHServer: @property def on_ssh_channel_request() -> Callable[[SSHServerSSHChannelRequestEventParams], None]: ... @on_ssh_channel_request.setter def on_ssh_channel_request(event_hook: Callable[[SSHServerSSHChannelRequestEventParams], None]) -> None: ... ``` ## Remarks The client 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. *ConnectionId* identifies the connection making the request. *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, [on_ssh_channel_requested](#on_ssh_channel_requested-event) will fire with the same information in case the request requires further processing. 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. # on_ssh_channel_requested event Fired if the SSHChannelRequest was successful, any further processing for the channel request should be done here. ## Syntax ```text class SSHServerSSHChannelRequestedEventParams(object): @property def connection_id() -> int: ... @property def channel_id() -> int: ... @property def request_type() -> str: ... @property def packet() -> bytes: ... # In class SSHServer: @property def on_ssh_channel_requested() -> Callable[[SSHServerSSHChannelRequestedEventParams], None]: ... @on_ssh_channel_requested.setter def on_ssh_channel_requested(event_hook: Callable[[SSHServerSSHChannelRequestedEventParams], None]) -> None: ... ``` ## Remarks The client 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. *ConnectionId* identifies the connection making the request. *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. 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. # on_ssh_service_request event Fired when a client requests a service to be started. ## Syntax ```text class SSHServerSSHServiceRequestEventParams(object): @property def connection_id() -> int: ... @property def service() -> str: ... @property def accept() -> bool: ... @accept.setter def accept(value) -> None: ... # In class SSHServer: @property def on_ssh_service_request() -> Callable[[SSHServerSSHServiceRequestEventParams], None]: ... @on_ssh_service_request.setter def on_ssh_service_request(event_hook: Callable[[SSHServerSSHServiceRequestEventParams], None]) -> None: ... ``` ## Remarks The on_ssh_service_request event is fired when a client requests that a service be started for a particular connection, identified by *ConnectionId*. *Service* will be the name of the service the client wishes to start. If the connection is authenticated and the user has access to the service, set *Accept* to True to allow the SSHServer to accept the request. 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. # on_ssh_status event Fired to show the progress of the secure connection. ## Syntax ```text class SSHServerSSHStatusEventParams(object): @property def connection_id() -> int: ... @property def message() -> str: ... # In class SSHServer: @property def on_ssh_status() -> Callable[[SSHServerSSHStatusEventParams], None]: ... @on_ssh_status.setter def on_ssh_status(event_hook: Callable[[SSHServerSSHStatusEventParams], None]) -> None: ... ``` ## Remarks This event is fired for informational and logging purposes only. It is used to track the progress of the connection. # on_ssh_tunnel_closed event Fired when a connected client attempts to close a tunnel. ## Syntax ```text class SSHServerSSHTunnelClosedEventParams(object): @property def connection_id() -> int: ... @property def address() -> str: ... @property def port() -> int: ... # In class SSHServer: @property def on_ssh_tunnel_closed() -> Callable[[SSHServerSSHTunnelClosedEventParams], None]: ... @on_ssh_tunnel_closed.setter def on_ssh_tunnel_closed(event_hook: Callable[[SSHServerSSHTunnelClosedEventParams], None]) -> None: ... ``` ## Remarks This functionality is not yet implemented. This event fires when the connected client attempts to close a forward or reverse tunnel. # on_ssh_tunnel_requested event Fired when a connected client attempts to establish a forward or reverse tunnel. ## Syntax ```text class SSHServerSSHTunnelRequestedEventParams(object): @property def connection_id() -> int: ... @property def direction() -> int: ... @property def address() -> str: ... @property def port() -> int: ... @port.setter def port(value) -> None: ... @property def accept() -> bool: ... @accept.setter def accept(value) -> None: ... # In class SSHServer: @property def on_ssh_tunnel_requested() -> Callable[[SSHServerSSHTunnelRequestedEventParams], None]: ... @on_ssh_tunnel_requested.setter def on_ssh_tunnel_requested(event_hook: Callable[[SSHServerSSHTunnelRequestedEventParams], None]) -> None: ... ``` ## Remarks This functionality is not yet implemented. This event fires when the connected client attempts to establish a forward or reverse tunnel. A forward tunnel, after being established, will forward all traffic from the client to a specified hostname and port. A reverse tunnel, after being established, will listen for incoming traffic on the same machine where [SSHServer](#sshserver-class) is running and any data received on that port will be forwarded to the client who requested the reverse tunnel. # on_ssh_user_auth_request event Fired when a client attempts to authenticate a connection. ## Syntax ```text class SSHServerSSHUserAuthRequestEventParams(object): @property def connection_id() -> int: ... @property def user() -> str: ... @property def service() -> str: ... @property def auth_method() -> str: ... @property def auth_param() -> str: ... @property def accept() -> bool: ... @accept.setter def accept(value) -> None: ... @property def partial_success() -> bool: ... @partial_success.setter def partial_success(value) -> None: ... @property def available_methods() -> str: ... @available_methods.setter def available_methods(value) -> None: ... @property def key_algorithm() -> str: ... # In class SSHServer: @property def on_ssh_user_auth_request() -> Callable[[SSHServerSSHUserAuthRequestEventParams], None]: ... @on_ssh_user_auth_request.setter def on_ssh_user_auth_request(event_hook: Callable[[SSHServerSSHUserAuthRequestEventParams], None]) -> None: ... ``` ## Remarks The on_ssh_user_auth_request event fires when a Secure Shell (SSH) client attempts to authenticate itself on a particular connection. *ConnectionId* will identify the connection being authenticated. *User* will be the name of the account requesting authentication, and *Service* will contain the name of the service the client is wishing to access. *AuthMethod* will denote which method the client is attempting to use to authenticate itself. *AuthParam* will contain the value of the authentication token used by the client. If the token is acceptable, you may set *Accept* to True to allow the class to authenticate the client. If it is not, set *Accept* to False. Connecting clients will initially attempt authentication with an *AuthMethod* of "none". This is done with the expectation that the request will fail and the server will send a list of supported methods back to the client. In your implementation, check the *AuthMethod* parameter; if it is "none", you should set *AvailableMethods* and reject the request. The client will select one of the available methods and reauthenticate. You may set *AvailableMethods* to a comma-delimited string of authentication methods that are available for the user. This list will be sent back to the client so that it may perform further authentication attempts. The following is a list of methods implemented by the class: | | | | --- | --- | | none | This authentication method is used by most Secure Shell (SSH) clients to obtain the list of authentication methods available for the user's account. In most cases, you should not accept a request using this authentication method. | | password | AuthParam will contain the user-supplied password. If the password is correct, set Accept to True. | | publickey | AuthParam will contain an SSH2 public key blob. If the user's public key is acceptable, set Accept or PartialSuccess to True. The class will then handle verifying the digital signature and will respond to the client accordingly. | | keyboard-interactive | on_ssh_user_auth_request will fire multiple times for keyboard-interactive authentication: It will fire once for each response sent by the client in the SSH_MSG_USERAUTH_INFO_RESPONSE packet (one time for each prompt specified by the daemon). The index of each response will be specified as a suffix in AuthMethod, with AuthParam containing the response to the corresponding prompt (e.g., keyboard-interactive-1, keyboard-interactive-2, and so on). Finally, on_ssh_user_auth_request will fire one last time with AuthMethod set to "keyboard-interactive" and AuthParam set to an empty string. The daemon must set Accept to True every time to allow the authentication process to succeed. | The *PartialSuccess* parameter is used only when multifactor authentication is needed. To implement multifactor authentication when this event fires, first verify the *AuthParam* for the given *AuthMethod*. If accepted, set *PartialSuccess* to True and *Accept* to False. The client should then send the authentication request for a different form of authentication specified in *AvailableMethods*. You may continue to set *PartialSuccess* to True until all authentication requirements are satisfied. Once all requirements are satisfied set *Accept* to True. *KeyAlgorithm* holds the signing algorithm used when the client attempts public key authentication. Possible values are as follows: - ssh-rsa - rsa-sha2-256 - rsa-sha2-512 - ssh-dss - ecdsa-sha2-nistp256 - ecdsa-sha2-nistp384 - ecdsa-sha2-nistp521 - x509v3-sign-rsa - x509v3-sign-dss 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. # SSHServer Config Settings 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](#config-method) method. ### SSHServer Config Settings **AltSSHCertCount**: The number of records in the AltSSHCert configuration settings.This configuration setting controls the size of the following arrays: - [AltSSHCertStore](#AltSSHCertStore) - [AltSSHCertStorePassword](#AltSSHCertStorePassword) - [AltSSHCertStoreType](#AltSSHCertStoreType) - [AltSSHCertSubject](#AltSSHCertSubject) The array indices start at *0* and end at *AltSSHCertCount - 1*. The AltSSHCert configuration settings are used to specify alternative digital certificates to the one set using the ssh_cert. The server will determine the certificate to use during Secure Shell (SSH) negotiation based on the public key algorithm requested by the connecting client. A certificate with a private key is required for session authentication and encryption. The [AltSSHCertSubject](#AltSSHCertSubject) setting must be set last. When [AltSSHCertSubject](#AltSSHCertSubject) is set, a search is initiated in the [AltSSHCertStore](#AltSSHCertStore) and the certificate is loaded. The alternative server certificate specified by these settings must be configured before setting [listening](#listening-property) to *True*. For example: ```csharp sftpserver.Config("AltSSHCertCount =1"); sftpserver.Config("AltSSHCertStoreType[0]=7"); //PEM Key Blob sftpserver.Config("AltSSHCertStore[0]=" + ed25519Key); //PEM formatted string sftpserver.Config("AltSSHCertSubject[0]=*"); //Load the first (and only) certificate ``` **AltSSHCertStore[i]**: The name of the certificate store.The name of the certificate store. This configuration setting is used when specifying an alternative ssh_cert. The [AltSSHCertStoreType](#AltSSHCertStoreType) specifies the type of the certificate store specified by [AltSSHCertStore](#AltSSHCertStore). If the store is password protected, specify the password in the [AltSSHCertStorePassword](#AltSSHCertStorePassword). [AltSSHCertStore](#AltSSHCertStore) is used in conjunction with the [AltSSHCertSubject](#AltSSHCertSubject) field to specify the certificate. 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. | 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). **AltSSHCertStorePassword[i]**: The password used to open the certificate store.If the certificate store requires a password, this configuration setting can be used to specify that password. This setting is used when specifying an alternative ssh_cert **AltSSHCertStoreType[i]**: The type of certificate store.This configuration setting specifies the type of certificate store. This setting is used when specifying an alternate ssh_cert. Possible values are as follows: | | | | --- | --- | | 0 | User - This is the 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 | Machine - For Windows, this specifies that the certificate store is a machine store. NOTE: This store type is not available in Java. | | 2 | PFXFile - The certificate store is the name of a PFX (PKCS12) file containing certificates. | | 3 | PFXBlob - The certificate store is a string (binary or Base64-encoded) representing a certificate store in PFX (PKCS12) format. | | 4 | JKSFile - The certificate store is the name of a Java Key Store (JKS) file containing certificates. NOTE: This store type is available only in Java. | | 5 | JKSBlob - 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 available only in Java. | | 6 | PEMKeyFile - The certificate store is the name of a PEM-encoded file that contains a private key and an optional certificate. | | 7 | PEMKeyBlob - The certificate store is a string (binary or Base64-encoded) that contains a private key and an optional certificate. | | 14 | PPKFile - The certificate store is the name of a file that contains a PPK (PuTTY Private Key). | | 15 | PPKBlob - The certificate store is a string (binary) that contains a PPK (PuTTY Private Key). | | 16 | XMLFile - The certificate store is the name of a file that contains a certificate in XML format. | | 17 | XMLBlob - The certificate store is a string that contains a certificate in XML format. | **AltSSHCertSubject[i]**: The alternative certificate subject.The subject of the certificate. This configuration setting is used when specifying an alternative ssh_cert. The special value of *** may be used to select the first certificate in the store. **ClientSSHVersionString[ConnectionId]**: The client's version string.This configuration setting returns a connected client's SSH version string. It may be queried inside [on_ssh_user_auth_request](#on_ssh_user_auth_request-event). ```csharp sftpserver1.OnSSHUserAuthRequest += (obj, ev) => { Console.WriteLine(sftpserver1.Config("ClientSSHVersionString[" + ev.ConnectionId + "]")); }; ``` **FireAuthRequestAfterSig**: Whether to fire an informational event after the public key signature has been verified.When performing public key authentication, the connecting client will present both the public key as well as a signature to verify ownership of the corresponding private key. The class will automatically verify the signature and respond to the client to indicate whether the signature could be verified and the connection can continue. This configuration setting controls whether an additional informational event fires to report the result of the signature verification. If set to *true*, the [on_ssh_user_auth_request](#on_ssh_user_auth_request-event) event will fire twice per public key authentication attempt. The first time the event fires for public key authentication as usual. After verification of the signature has taken place, the [on_ssh_user_auth_request](#on_ssh_user_auth_request-event) will fire again, and the *AuthMethod* parameter will contain the string *sigstatus*. The *AuthParam* parameter will contain a value of *0* (invalid signature) or *1* (valid signature). If the signature is invalid, it will always result in a rejected authentication attempt. **KeyboardInteractivePrompts[ConnectionId]**: Specifies custom keyboard-interactive prompts for particular connections.By default, setting the keyboard_interactive_prompts property will cause those prompts to be used for every user attempting to connect. This setting can be used to override the keyboard_interactive_prompts property and provide unique prompts for certain connections. This configuration setting takes a list of prompts to display to the client, and each prompt includes an 'echo' parameter to specify whether or not to echo the client's response to the prompt. The prompt and the echo parameter should be separated by a comma (","), and each prompt should be separated by a semicolon (";"). For example: "KeyboardInteractivePrompts[connId]=First prompt,echo=false;Second prompt,echo=true" This configuration setting can be set anywhere in code, but it is necessary to know the ConnectionId for the specific connection beforehand; as such, it is generally recommended to set this configuration inside the [on_ssh_user_auth_request](#on_ssh_user_auth_request-event) event. Because connecting clients initially attempt to connect with and *AuthMethod* of 'none' (with the understanding that this attempt will fail, and the SSH server will advertise which authentication methods it supports), it is recommended to check the *AuthMethod*, *User*, and *ConnectionId* parameters of the [on_ssh_user_auth_request](#on_ssh_user_auth_request-event) event and set this configuration setting accordingly. When SSHServer displays keyboard-interactive prompts, it will first check to see if this configuration setting is populated for the current ConnectionId. If it is, the prompts set here will be used instead of those set in the keyboard_interactive_prompts property. Otherwise, the keyboard_interactive_prompts property will function as normal. **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:** ```text 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 [on_log](#on_log-event) 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. | **MaxAuthAttempts**: The maximum authentication attempts allowed before forcing a disconnect.This configuration setting specifies the maximum amount of authentication attempts that will be allowed before forcibly disconnecting the client. **NegotiatedStrictKex[ConnectionId]**: Returns whether strict key exchange was negotiated to be used.Returns whether strict key exchange (strict kex) was negotiated during the SSH handshake. This is a per-connection configuration setting accessed by passing the ConnectionId. If strict kex is being used, then this will return *"True"*. If strict kex is not being used, then this will return *"False"*. ```text component.Config("NegotiatedStrictKex[connId]") ``` **ServerSSHVersionString**: The SSH version string sent to connecting clients.This configuration setting specifies the version string value that is sent to all connecting clients. This may be set to specify server specific information. The default value is "SSH-2.0-IPWorks SSH Daemon 2024". When setting your own value, it must begin with "SSH-2.0-" because this is a standard format that specifies the supported SSH version. **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](#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](#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](SSHReverseTunnel.md#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 - gss-group16-sha512 - gss-nistp256-sha256 - gss-curve25519-sha256 - gss-group14-sha1 - gss-gex-sha1 - mlkem768x25519-sha256 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,mlkem768x25519-sha256,diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,diffie-hellman-group1-sha1,gss-group14-sha256,gss-group16-sha512,gss-nistp256-sha256,gss-curve25519-sha256,gss-group14-sha1,gss-gex-sha1*. **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 allowed signature algorithms used by a client performing public key authentication.This configuration setting specifies a list of signature algorithms that a client is allowed to use when authenticating to the server using public key authentication. This applies only when public key authentication is performed by the client. The configuration setting should be a comma-separated list of algorithms. When a client connects, the server will verify that the client performing the public key authentication has used one of the specified signature algorithms. If the client uses a signature algorithm that is not in the list, the connection will be rejected. Possible values areas 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,x509v3-sign-rsa,ssh-dss,x509v3-sign-dss,ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,ssh-ed25519*. **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: ```text *SSH-1.99-*,*SSH-2.0-*,*SSH-2.99-* ``` **UserAuthBanner[ConnectionId]**: A custom user authentication banner.This configuration setting specifies a custom user authentication banner, which may be sent to give the client more information regarding an authentication attempt. "ConnectionId" specifies the particular connection to send the message to. This configuration option is effective only when set within the [on_ssh_user_auth_request](#on_ssh_user_auth_request-event) event. **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. | ### TCPServer Config Settings **AllowedClients**: A comma-separated list of host names or IP addresses that can access the class.This configuration setting defines a comma-separated list of host names or IPv4 addresses that may access the class. The wildcard character "*" is supported. The default value is "*" and all connections are accepted. When a client connects, the client's address is checked against the list defined here. If there is no match, the [on_connection_request](#on_connection_request-event) event fires with an *Accept* value set to *False*. If no action is taken within the [on_connection_request](#on_connection_request-event) event, the client will be disconnected. **BindExclusively**: Whether or not the component considers a local port reserved for exclusive use.If this is *True* (default), the component will bind to the local port with the ExclusiveAddressUse option set, meaning that nothing else can bind to the same port. Also the component will not be able to bind to local ports that are already in use by some other instance, and attempts to do so will result in failure. **BlockedClients**: A comma-separated list of host names or IP addresses that cannot access the class.This configuration setting defines a comma-separated list of host names or IPv4 addresses that cannot access the class.The default value is "" and all connections are accepted. When a client connects, the client's address is checked against the list defined here. If there is a match, the [on_connection_request](#on_connection_request-event) event fires with an *Accept* value set to *False*. If no action is taken within the [on_connection_request](#on_connection_request-event) event, the client will not be connected. **ConnectionUID**: The unique connectionId for a connection.Connection Ids may be reused as clients connect and disconnect. Querying ConnectionUID will return a unique identifier for that connection Id. If the specified connection Id does not exist, then ConnectionUID will return 0. For example: *Connection5UID = obj.config("ConnectionUID[5]")* **DefaultConnectionTimeout**: The inactivity timeout applied to the SSL handshake.This configuration setting specifies the inactivity (in seconds) to apply to incoming Secure Sockets Layer (SSL) connections. When set to a positive value, if the other end is unresponsive for the specified number of seconds, the connection will timeout. This is not applicable to the entire handshake. It is applicable only to the inactivity of the connecting client during the handshake if a response is expected and none is received within the timeout window. The default value is 0, and no connection-specific timeout is applied. NOTE: This is applicable only to incoming SSL connections. This should be set only if there is a specific reason to do so. **InBufferSize**: The size in bytes of the incoming queue of the socket. This is the size of an internal queue in the Transmission Control Protocol (TCP)/IP stack. You can increase or decrease its size depending on the amount of data that you will be receiving. Increasing the value of the [InBufferSize](#InBufferSize) setting can provide significant improvements in performance in some cases. Some TCP/IP implementations do not support variable buffer sizes. If that is the case, when the class is activated, the [InBufferSize](#InBufferSize) reverts to its defined size. The same thing will happen if you attempt to make it too large or too small. [InBufferSize](#InBufferSize) is shared among incoming connections. When the setting is set, the corresponding value is set for incoming connections as they are accepted. Existing connections are not modified. **KeepAliveInterval**: The retry interval, in milliseconds, to be used when a TCP keep-alive packet is sent and no response is received.A TCP keep-alive packet will be sent after a period of inactivity, as defined by [KeepAliveTime](#KeepAliveTime). If no acknowledgment is received from the remote host, the keep-alive packet will be sent again. This setting specifies the interval at which the successive keep-alive packets are sent in milliseconds. If this value is not specified here, the system default is 1 second. This setting is applicable to all connections. NOTE: This value is not applicable in macOS. **KeepAliveRetryCount**: The number of keep-alive packets to be sent before the remotehost is considered disconnected.A TCP keep-alive packet will be sent after a period of inactivity, as defined by [KeepAliveTime](#KeepAliveTime). If no acknowledgment is received from the remote host, the keep-alive packet will be sent again. This setting specifies the number of times that the keep-alive packets will be sent again before the remote host is considered disconnected. If this value is not specified here, the system default is 9. NOTE: This configuration setting is available only in the Unix platform, and it is not supported in macOS or FreeBSD. **KeepAliveTime**: The inactivity time in milliseconds before a TCP keep-alive packet is sent.By default, the operating system will determine the time a connection is idle before a TCP keep-alive packet is sent. If this value is not specified here, the system default is 2 hours. In many cases, a shorter interval is more useful. Set this value to the desired interval in milliseconds. This setting is applicable to all connections. **MaxConnections**: The maximum number of connections available. This is the maximum number of connections available. This setting must be set before [listening](#listening-property) is set to *True*, and once set, it can no longer be changed for the current instance of the class. The maximum value for this setting is 100,000 connections. Use this setting with caution. Extremely large values may affect performance. The default value is 1000. NOTE: Unix/Linux operating systems limit the number of simultaneous connections to 1024. **MaxReadTime**: The maximum time spent reading data from each connection.This setting specifies the maximum time in milliseconds that the class will spend reading data from a particular connection before servicing other connections. When a single client is sending data to the class at a high rate this setting is used to ensure that other connections are serviced in a timely manner. Specifying a positive value prevents a single client from monopolizing the class's resources. The special value of *0* indicates no limit and is generally not recommended. The default value is *50* (milliseconds). **OutBufferSize**: The size in bytes of the outgoing queue of the socket.This is the size of an internal queue in the TCP/IP stack. You can increase or decrease its size depending on the amount of data that you will be sending. Increasing the value of the [OutBufferSize](#OutBufferSize) setting can provide significant improvements in performance in some cases. Some TCP/IP implementations do not support variable buffer sizes. If that is the case, when the class is activated the [OutBufferSize](#OutBufferSize) reverts to its defined size. The same thing will happen if you attempt to make it too large or too small. [OutBufferSize](#OutBufferSize) is shared among incoming connections. When the setting is set, the corresponding value is set for incoming connections as they are accepted. Existing connections are not modified. **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. **UseIOCP**: Whether to use the completion port I/O model.The default value is *False*. When set to *True*, the class will use an I/O Completion Port (IOCP) to manage operations on sockets. A single completion port allows the asynchronous notification of network events on an entire group of sockets. This setting must be set before [listening](#listening-property) is set to *True*. Nothing else is required to begin accepting IOCP connections. One major benefit to using this model is that there will be no thread blocked waiting for a request to complete. The system notifies the process through an Asynchronous Procedure Call (APC) once the device driver finishes servicing the I/O request. IOCP allows a single I/O worker thread handle multiple clients' input/output "fairly". NOTE: When set to *True*, this setting will automatically set [UseWindowsMessages](#UseWindowsMessages) to *False*. **UseIPv6**: Whether to use IPv6.When set to 0 (default), the class will use IPv4 exclusively. When set to 1, the class will use IPv6 exclusively. When set to 2, the class will listen for both IPv4 and IPv6 connections. If IPv6 is not available on the system, only IPv4 will be used. The default value is 0. Possible values are as follows: | | | | --- | --- | | 0 | IPv4 Only | | 1 | IPv6 Only | | 2 | IPv6 and IPv4 | **UseWindowsMessages**: Whether to use the WSAAsyncSelect I/O model.The default value is *True*, and the class will receive a Windows message-based notification of network events. Turning on Windows message notifications allows the application to get connect, send, receive, and socket closure network event notifications on a socket. This setting must be set before [listening](#listening-property) is set to *True*. Nothing else is required to begin accepting connections using the Windows message queue. In high-traffic environments, messages will be discarded if the queue is full. Additionally, because a single window procedure will service all events on thousands of sockets, the Windows message queue is not scalable from a performance perspective. If this setting is set to *False*, the class will instead use the Winsock *select* model instead. ### 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. **CodePage**: The system code page used for Unicode to Multibyte translations.The default code page is Unicode UTF-8 (65001). The following is a list of valid code page identifiers: | | | | --- | --- | | Identifier | Name | | 037 | IBM EBCDIC - U.S./Canada | | 437 | OEM - United States | | 500 | IBM EBCDIC - International | | 708 | Arabic - ASMO 708 | | 709 | Arabic - ASMO 449+, BCON V4 | | 710 | Arabic - Transparent Arabic | | 720 | Arabic - Transparent ASMO | | 737 | OEM - Greek (formerly 437G) | | 775 | OEM - Baltic | | 850 | OEM - Multilingual Latin I | | 852 | OEM - Latin II | | 855 | OEM - Cyrillic (primarily Russian) | | 857 | OEM - Turkish | | 858 | OEM - Multilingual Latin I + Euro symbol | | 860 | OEM - Portuguese | | 861 | OEM - Icelandic | | 862 | OEM - Hebrew | | 863 | OEM - Canadian-French | | 864 | OEM - Arabic | | 865 | OEM - Nordic | | 866 | OEM - Russian | | 869 | OEM - Modern Greek | | 870 | IBM EBCDIC - Multilingual/ROECE (Latin-2) | | 874 | ANSI/OEM - Thai (same as 28605, ISO 8859-15) | | 875 | IBM EBCDIC - Modern Greek | | 932 | ANSI/OEM - Japanese, Shift-JIS | | 936 | ANSI/OEM - Simplified Chinese (PRC, Singapore) | | 949 | ANSI/OEM - Korean (Unified Hangul Code) | | 950 | ANSI/OEM - Traditional Chinese (Taiwan; Hong Kong SAR, PRC) | | 1026 | IBM EBCDIC - Turkish (Latin-5) | | 1047 | IBM EBCDIC - Latin 1/Open System | | 1140 | IBM EBCDIC - U.S./Canada (037 + Euro symbol) | | 1141 | IBM EBCDIC - Germany (20273 + Euro symbol) | | 1142 | IBM EBCDIC - Denmark/Norway (20277 + Euro symbol) | | 1143 | IBM EBCDIC - Finland/Sweden (20278 + Euro symbol) | | 1144 | IBM EBCDIC - Italy (20280 + Euro symbol) | | 1145 | IBM EBCDIC - Latin America/Spain (20284 + Euro symbol) | | 1146 | IBM EBCDIC - United Kingdom (20285 + Euro symbol) | | 1147 | IBM EBCDIC - France (20297 + Euro symbol) | | 1148 | IBM EBCDIC - International (500 + Euro symbol) | | 1149 | IBM EBCDIC - Icelandic (20871 + Euro symbol) | | 1200 | Unicode UCS-2 Little-Endian (BMP of ISO 10646) | | 1201 | Unicode UCS-2 Big-Endian | | 1250 | ANSI - Central European | | 1251 | ANSI - Cyrillic | | 1252 | ANSI - Latin I | | 1253 | ANSI - Greek | | 1254 | ANSI - Turkish | | 1255 | ANSI - Hebrew | | 1256 | ANSI - Arabic | | 1257 | ANSI - Baltic | | 1258 | ANSI/OEM - Vietnamese | | 1361 | Korean (Johab) | | 10000 | MAC - Roman | | 10001 | MAC - Japanese | | 10002 | MAC - Traditional Chinese (Big5) | | 10003 | MAC - Korean | | 10004 | MAC - Arabic | | 10005 | MAC - Hebrew | | 10006 | MAC - Greek I | | 10007 | MAC - Cyrillic | | 10008 | MAC - Simplified Chinese (GB 2312) | | 10010 | MAC - Romania | | 10017 | MAC - Ukraine | | 10021 | MAC - Thai | | 10029 | MAC - Latin II | | 10079 | MAC - Icelandic | | 10081 | MAC - Turkish | | 10082 | MAC - Croatia | | 12000 | Unicode UCS-4 Little-Endian | | 12001 | Unicode UCS-4 Big-Endian | | 20000 | CNS - Taiwan | | 20001 | TCA - Taiwan | | 20002 | Eten - Taiwan | | 20003 | IBM5550 - Taiwan | | 20004 | TeleText - Taiwan | | 20005 | Wang - Taiwan | | 20105 | IA5 IRV International Alphabet No. 5 (7-bit) | | 20106 | IA5 German (7-bit) | | 20107 | IA5 Swedish (7-bit) | | 20108 | IA5 Norwegian (7-bit) | | 20127 | US-ASCII (7-bit) | | 20261 | T.61 | | 20269 | ISO 6937 Non-Spacing Accent | | 20273 | IBM EBCDIC - Germany | | 20277 | IBM EBCDIC - Denmark/Norway | | 20278 | IBM EBCDIC - Finland/Sweden | | 20280 | IBM EBCDIC - Italy | | 20284 | IBM EBCDIC - Latin America/Spain | | 20285 | IBM EBCDIC - United Kingdom | | 20290 | IBM EBCDIC - Japanese Katakana Extended | | 20297 | IBM EBCDIC - France | | 20420 | IBM EBCDIC - Arabic | | 20423 | IBM EBCDIC - Greek | | 20424 | IBM EBCDIC - Hebrew | | 20833 | IBM EBCDIC - Korean Extended | | 20838 | IBM EBCDIC - Thai | | 20866 | Russian - KOI8-R | | 20871 | IBM EBCDIC - Icelandic | | 20880 | IBM EBCDIC - Cyrillic (Russian) | | 20905 | IBM EBCDIC - Turkish | | 20924 | IBM EBCDIC - Latin-1/Open System (1047 + Euro symbol) | | 20932 | JIS X 0208-1990 & 0121-1990 | | 20936 | Simplified Chinese (GB2312) | | 21025 | IBM EBCDIC - Cyrillic (Serbian, Bulgarian) | | 21027 | Extended Alpha Lowercase | | 21866 | Ukrainian (KOI8-U) | | 28591 | ISO 8859-1 Latin I | | 28592 | ISO 8859-2 Central Europe | | 28593 | ISO 8859-3 Latin 3 | | 28594 | ISO 8859-4 Baltic | | 28595 | ISO 8859-5 Cyrillic | | 28596 | ISO 8859-6 Arabic | | 28597 | ISO 8859-7 Greek | | 28598 | ISO 8859-8 Hebrew | | 28599 | ISO 8859-9 Latin 5 | | 28605 | ISO 8859-15 Latin 9 | | 29001 | Europa 3 | | 38598 | ISO 8859-8 Hebrew | | 50220 | ISO 2022 Japanese with no halfwidth Katakana | | 50221 | ISO 2022 Japanese with halfwidth Katakana | | 50222 | ISO 2022 Japanese JIS X 0201-1989 | | 50225 | ISO 2022 Korean | | 50227 | ISO 2022 Simplified Chinese | | 50229 | ISO 2022 Traditional Chinese | | 50930 | Japanese (Katakana) Extended | | 50931 | US/Canada and Japanese | | 50933 | Korean Extended and Korean | | 50935 | Simplified Chinese Extended and Simplified Chinese | | 50936 | Simplified Chinese | | 50937 | US/Canada and Traditional Chinese | | 50939 | Japanese (Latin) Extended and Japanese | | 51932 | EUC - Japanese | | 51936 | EUC - Simplified Chinese | | 51949 | EUC - Korean | | 51950 | EUC - Traditional Chinese | | 52936 | HZ-GB2312 Simplified Chinese | | 54936 | Windows XP: GB18030 Simplified Chinese (4 Byte) | | 57002 | ISCII Devanagari | | 57003 | ISCII Bengali | | 57004 | ISCII Tamil | | 57005 | ISCII Telugu | | 57006 | ISCII Assamese | | 57007 | ISCII Oriya | | 57008 | ISCII Kannada | | 57009 | ISCII Malayalam | | 57010 | ISCII Gujarati | | 57011 | ISCII Punjabi | | 65000 | Unicode UTF-7 | | 65001 | Unicode UTF-8 | The following is a list of valid code page identifiers for Mac OS only: | | | | --- | --- | | Identifier | Name | | 1 | ASCII | | 2 | NEXTSTEP | | 3 | JapaneseEUC | | 4 | UTF8 | | 5 | ISOLatin1 | | 6 | Symbol | | 7 | NonLossyASCII | | 8 | ShiftJIS | | 9 | ISOLatin2 | | 10 | Unicode | | 11 | WindowsCP1251 | | 12 | WindowsCP1252 | | 13 | WindowsCP1253 | | 14 | WindowsCP1254 | | 15 | WindowsCP1250 | | 21 | ISO2022JP | | 30 | MacOSRoman | | 10 | UTF16String | | 0x90000100 | UTF16BigEndian | | 0x94000100 | UTF16LittleEndian | | 0x8c000100 | UTF32String | | 0x98000100 | UTF32BigEndian | | 0x9c000100 | UTF32LittleEndian | | 65536 | Proprietary | **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*. **ProcessIdleEvents**: Whether the class uses its internal event loop to process events when the main thread is idle.If set to False, the class will not fire internal idle events. Set this to False to use the class in a background thread on Mac OS. By default, this setting is True. **SelectWaitMillis**: The length of time in milliseconds the class will wait when DoEvents is called if there are no events to process.If there are no events to process when [do_events](#do_events-method) is called, the class will wait for the amount of time specified here before returning. The default value is 20. **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. 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](https://www.nsoftware.com/kb/articles/fips.rst) article. NOTE: This setting is applicable only on Windows. NOTE: Enabling FIPS compliance requires a special license; please contact [sales@nsoftware.com](mailto: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. On Windows, this setting is set to *False* by default. On Linux/macOS, this setting is set to *True* by default. To use the system security libraries for Linux, OpenSSL support must be enabled. For more information on how to enable OpenSSL, please refer to the [OpenSSL Notes](platforms.md) section. # SSHServer Errors ### SSHServer Errors | | | | --- | --- | | 1201 | Could not forward connection. A detailed message follows. | | 1202 | Could not forward connection/channel data. A detailed message follows. | | 1300 | Could not authenticate client. | | 1301 | No server certificate was specified or no private key found. | ### TCPServer Errors | | | | --- | --- | | 100 | You cannot change the remote_port at this time. A connection is in progress. | | 101 | You cannot change the remote_host at this time. A connection is in progress. | | 102 | The remote_host address is invalid (0.0.0.0). | | 104 | TCPServer is already listening. | | 106 | Cannot change [local_port](#local_port-property) when TCPServer is listening. | | 107 | Cannot change [local_host](#local_host-property) when TCPServer is listening. | | 108 | Cannot change [MaxConnections](#MaxConnections) when TCPServer is listening. | | 112 | You cannot change [MaxLineLength](#MaxLineLength) at this time. A connection is in progress. | | 116 | remote_port cannot be zero. Please specify a valid service port number. | | 126 | Invalid ConnectionId. | | 135 | Operation would block. | ### 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). |