Package org.apache.sshd.common.session

Interface ReservedSessionMessagesHandler

All Superinterfaces:

EventListener, SshdEventListener

All Known Implementing Classes:

ReservedSessionMessagesHandlerAdapter

public interface ReservedSessionMessagesHandler
extends SshdEventListener

Provides a way to listen and handle the SSH_MSG_IGNORE and SSH_MSG_DEBUG messages that are received by a session, as well as proprietary and/or extension messages and behavior.

Author:

Apache MINA SSHD Project

Method Summary

Modifier and Type	Method	Description
default void	handleDebugMessage(Session session, Buffer buffer)	Invoked when an SSH_MSG_DEBUG packet is received
default void	handleIgnoreMessage(Session session, Buffer buffer)	Invoked when an SSH_MSG_IGNORE packet is received
default boolean	handleUnimplementedMessage(Session session, int cmd, Buffer buffer)	Invoked when a packet with an un-implemented message is received - including SSH_MSG_UNIMPLEMENTED itself
default IoWriteFuture	sendIdentification(Session session, String version, List<String> extraLines)	Send the initial version exchange identification in and independent manner
default IoWriteFuture	sendKexInitRequest(Session session, Map<KexProposalOption,String> proposal, Buffer packet)	Invoked before sending the SSH_MSG_KEXINIT packet
default boolean	sendReservedHeartbeat(ConnectionService service)	Invoked if the user configured usage of a proprietary heartbeat mechanism.

Method Detail

sendIdentification

default IoWriteFuture sendIdentification(Session session,
                                         String version,
                                         List<String> extraLines)
                                  throws Exception

Send the initial version exchange identification in and independent manner

Parameters:

session - The Session through which the version is exchange is being managed

version - The version line that was resolved - Note: since this string is part of the KEX and is cached in the calling session, any changes to it require updating the session's cached value.

extraLines - Extra lines to be sent - valid only for server sessions. Note:/B> the handler may modify these lines and return null thus signaling the session to proceed with sending the identification

Returns:

A IoWriteFuture that can be used to wait for the data to be sent successfully. If null then the session will send the identification, otherwise it is assumed that the handler has sent it.

Throws:

Exception - if failed to handle the callback

See Also:

RFC 4253 - section 4.2 - Protocol Version Exchange

sendKexInitRequest

default IoWriteFuture sendKexInitRequest(Session session,
                                         Map<KexProposalOption,String> proposal,
                                         Buffer packet)
                                  throws Exception

Invoked before sending the SSH_MSG_KEXINIT packet

Parameters:

session - The Session through which the key exchange is being managed

proposal - The KEX proposal that was used to build the packet

packet - The packet containing the fully encoded message - Caveat: this packet later serves as part of the key generation, so care must be taken if manipulating it.

Returns:

A non-null IoWriteFuture to signal that handler took care of the KEX packet delivery.

Throws:

Exception - if failed to handle the callback

handleIgnoreMessage

default void handleIgnoreMessage(Session session,
                                 Buffer buffer)
                          throws Exception

Invoked when an SSH_MSG_IGNORE packet is received

Parameters:

session - The Session through which the message was received

buffer - The Buffer containing the data

Throws:

Exception - If failed to handle the message

See Also:

RFC 4253 - section 11.2

handleDebugMessage

default void handleDebugMessage(Session session,
                                Buffer buffer)
                         throws Exception

Invoked when an SSH_MSG_DEBUG packet is received

Parameters:

session - The Session through which the message was received

buffer - The Buffer containing the data

Throws:

Exception - If failed to handle the message

See Also:

RFC 4253 - section 11.3

handleUnimplementedMessage

default boolean handleUnimplementedMessage(Session session,
                                           int cmd,
                                           Buffer buffer)
                                    throws Exception

Invoked when a packet with an un-implemented message is received - including SSH_MSG_UNIMPLEMENTED itself

Parameters:

session - The Session through which the message was received

cmd - The received (un-implemented) command

buffer - The Buffer containing the data - positioned just beyond the command

Returns:

true if message handled internally, false if should return a SSH_MSG_UNIMPLEMENTED reply (default behavior)

Throws:

Exception - If failed to handle the message

See Also:

RFC 4253 - section 11.4

sendReservedHeartbeat

default boolean sendReservedHeartbeat(ConnectionService service)
                               throws Exception

Invoked if the user configured usage of a proprietary heartbeat mechanism. Note: by default throws UnsupportedOperationException so users who configure a proprietary heartbeat mechanism option must provide an implementation for this method.

Parameters:

service - The ConnectionService through which the heartbeat is being executed.

Returns:

true whether heartbeat actually sent - Note: used mainly for debugging purposes.

Throws:

Exception - If failed to send the heartbeat - Note: causes associated session termination.