org.apache.sshd.common.kex.extension

Class DefaultClientKexExtensionHandler

java.lang.Object

org.apache.sshd.common.util.logging.AbstractLoggingBean

org.apache.sshd.common.kex.extension.DefaultClientKexExtensionHandler

All Implemented Interfaces:

KexExtensionHandler

public class DefaultClientKexExtensionHandler
extends AbstractLoggingBean
implements KexExtensionHandler

Detects if the server sends a "server-sig-algs" and updates the client session by adding the "rsa-sha2-256/512" signature factories (if not already added). Note: experimental - used for development purposes and as an example

Author:

Apache MINA SSHD Project

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.sshd.common.kex.extension.KexExtensionHandler

KexExtensionHandler.AvailabilityPhase, KexExtensionHandler.KexPhase

Field Summary

Fields

Modifier and Type	Field and Description
static AttributeRepository.AttributeKey<Map<KexProposalOption,String>>	CLIENT_PROPOSAL_KEY Session AttributeRepository.AttributeKey used to store the client's proposal
static NavigableSet<String>	DEFAULT_EXTRA_SIGNATURES
static DefaultClientKexExtensionHandler	INSTANCE
static AttributeRepository.AttributeKey<Map<KexProposalOption,String>>	SERVER_PROPOSAL_KEY Session AttributeRepository.AttributeKey used to store the server's proposal

Fields inherited from class org.apache.sshd.common.util.logging.AbstractLoggingBean

log

Constructor Summary

Constructors

Constructor and Description
DefaultClientKexExtensionHandler()

Method Summary

Modifier and Type	Method and Description
boolean	handleKexExtensionRequest(Session session, int index, int count, String name, byte[] data) Invoked by KexExtensionHandler.handleKexExtensionsMessage(Session, Buffer) in order to handle a specific extension.
void	handleKexInitProposal(Session session, boolean initiator, Map<KexProposalOption,String> proposal) Invoked when a peer is ready to send the KEX options proposal or has received such a proposal.
boolean	isKexExtensionsAvailable(Session session, KexExtensionHandler.AvailabilityPhase phase)
int	resolvePreferredSignaturePosition(Session session, List<? extends NamedFactory<Signature>> factories, NamedFactory<Signature> factory)
List<NamedFactory<Signature>>	resolveRequestedSignatureFactories(Session session, Collection<String> extraAlgos)
NamedFactory<Signature>	resolveRequestedSignatureFactory(Session session, String name)
List<NamedFactory<Signature>>	resolveUpdatedSignatureFactories(Session session, List<NamedFactory<Signature>> available, Collection<String> extraAlgos) Checks if the extra signature algorithms are already included in the available ones, and adds the extra ones (if supported).
List<NamedFactory<Signature>>	updateAvailableSignatureFactories(Session session, Collection<String> extraAlgos)
List<NamedFactory<Signature>>	updateAvailableSignatureFactories(Session session, List<NamedFactory<Signature>> available, Collection<? extends NamedFactory<Signature>> toAdd)

Methods inherited from class org.apache.sshd.common.util.logging.AbstractLoggingBean

getSimplifiedLogger

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.apache.sshd.common.kex.extension.KexExtensionHandler

handleKexCompressionMessage, handleKexExtensionNegotiation, handleKexExtensionsMessage, sendKexExtensions

Field Detail

CLIENT_PROPOSAL_KEY

public static final AttributeRepository.AttributeKey<Map<KexProposalOption,String>> CLIENT_PROPOSAL_KEY

Session AttributeRepository.AttributeKey used to store the client's proposal

SERVER_PROPOSAL_KEY

public static final AttributeRepository.AttributeKey<Map<KexProposalOption,String>> SERVER_PROPOSAL_KEY

Session AttributeRepository.AttributeKey used to store the server's proposal

DEFAULT_EXTRA_SIGNATURES

public static final NavigableSet<String> DEFAULT_EXTRA_SIGNATURES

INSTANCE

public static final DefaultClientKexExtensionHandler INSTANCE

Constructor Detail

DefaultClientKexExtensionHandler

public DefaultClientKexExtensionHandler()

Method Detail

isKexExtensionsAvailable

public boolean isKexExtensionsAvailable(Session session,
                                        KexExtensionHandler.AvailabilityPhase phase)
                                 throws IOException

Specified by:

isKexExtensionsAvailable in interface KexExtensionHandler

Parameters:

session - The Session about to execute KEX

phase - The KexExtensionHandler.AvailabilityPhase hint as to why the query is being made

Returns:

true whether to KEX extensions are supported/allowed for the session

Throws:

IOException - If failed to process the request

handleKexInitProposal

public void handleKexInitProposal(Session session,
                                  boolean initiator,
                                  Map<KexProposalOption,String> proposal)
                           throws IOException

Description copied from interface: KexExtensionHandler

Invoked when a peer is ready to send the KEX options proposal or has received such a proposal. Note: this method is called during the negotiation phase even if isKexExtensionsAvailable returns false for the session.

Specified by:

handleKexInitProposal in interface KexExtensionHandler

Parameters:

session - The Session initiating or receiving the proposal

initiator - true if the proposal is about to be sent, false if this is a proposal received from the peer.

proposal - The proposal contents - Caveat emptor: the proposal is modifiable i.e., the handler can modify before being sent or before being processed (if incoming)

Throws:

IOException - If failed to handle the request

handleKexExtensionRequest

public boolean handleKexExtensionRequest(Session session,
                                         int index,
                                         int count,
                                         String name,
                                         byte[] data)
                                  throws IOException

Description copied from interface: KexExtensionHandler

Invoked by KexExtensionHandler.handleKexExtensionsMessage(Session, Buffer) in order to handle a specific extension.

Specified by:

handleKexExtensionRequest in interface KexExtensionHandler

Parameters:

session - The Session through which the message was received

index - The 0-based extension index

count - The total extensions in the message

name - The extension name

data - The extension data

Returns:

true whether to proceed to the next extension or stop processing the rest

Throws:

IOException - If failed to handle the extension

updateAvailableSignatureFactories

public List<NamedFactory<Signature>> updateAvailableSignatureFactories(Session session,
                                                                       Collection<String> extraAlgos)
                                                                throws IOException

Throws:

IOException

resolveUpdatedSignatureFactories

public List<NamedFactory<Signature>> resolveUpdatedSignatureFactories(Session session,
                                                                      List<NamedFactory<Signature>> available,
                                                                      Collection<String> extraAlgos)
                                                               throws IOException

Checks if the extra signature algorithms are already included in the available ones, and adds the extra ones (if supported).

Parameters:

session - The Session for which the resolution occurs

available - The available signature factories

extraAlgos - The extra requested signatures - ignored if null/empty

Returns:

The resolved signature factories - same as input if nothing added

Throws:

IOException - If failed to resolve the factories

updateAvailableSignatureFactories

public List<NamedFactory<Signature>> updateAvailableSignatureFactories(Session session,
                                                                       List<NamedFactory<Signature>> available,
                                                                       Collection<? extends NamedFactory<Signature>> toAdd)
                                                                throws IOException

Throws:

IOException

resolvePreferredSignaturePosition

public int resolvePreferredSignaturePosition(Session session,
                                             List<? extends NamedFactory<Signature>> factories,
                                             NamedFactory<Signature> factory)
                                      throws IOException

Throws:

IOException

resolveRequestedSignatureFactories

public List<NamedFactory<Signature>> resolveRequestedSignatureFactories(Session session,
                                                                        Collection<String> extraAlgos)
                                                                 throws IOException

Throws:

IOException

resolveRequestedSignatureFactory

public NamedFactory<Signature> resolveRequestedSignatureFactory(Session session,
                                                                String name)
                                                         throws IOException

Throws:

IOException