jenkins.slaves

Class JnlpSlaveAgentProtocol

java.lang.Object

jenkins.AgentProtocol

jenkins.slaves.JnlpSlaveAgentProtocol

All Implemented Interfaces:

ExtensionPoint

@Extension
 @Symbol(value="jnlp")
public class JnlpSlaveAgentProtocol
extends AgentProtocol

AgentProtocol that accepts connection from agents.

Security

Once connected, remote agents can send in commands to be executed on the master, so in a way this is like an rsh service. Therefore, it is important that we reject connections from unauthorized remote agents.

We do this by computing HMAC of the agent name. This code is sent to the agent inside the .jnlp file (this file itself is protected by HTTP form-based authentication that we use everywhere else in Jenkins), and the agent sends this token back when it connects to the master. Unauthorized agents can't access the protected .jnlp file, so it can't impersonate a valid agent.

We don't want to force the inbound agents to be restarted whenever the server restarts, so right now this secret master key is generated once and used forever, which makes this whole scheme less secure.

Since:

1.467

Author:

Kohsuke Kawaguchi

Nested Class Summary

Nested classes/interfaces inherited from interface hudson.ExtensionPoint

ExtensionPoint.LegacyInstancesAreScopedToHudson

Field Summary

Fields

Modifier and Type	Field and Description
static HMACConfidentialKey	SLAVE_SECRET This secret value is used as a seed for agents.

Constructor Summary

Constructors

Constructor and Description
JnlpSlaveAgentProtocol()

Method Summary

Modifier and Type	Method and Description
String	getDisplayName() Returns the human readable protocol display name.
String	getName() Protocol name.
void	handle(Socket socket) Called by the connection handling thread to execute the protocol.
boolean	isDeprecated() Checks if the protocol is deprecated.
boolean	isOptIn() Allow experimental AgentProtocol implementations to declare being opt-in.
void	setHub(NioChannelSelector hub)

Methods inherited from class jenkins.AgentProtocol

all, isRequired, of

Methods inherited from class java.lang.Object

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

Field Detail

SLAVE_SECRET

public static final HMACConfidentialKey SLAVE_SECRET

This secret value is used as a seed for agents.

Constructor Detail

JnlpSlaveAgentProtocol

public JnlpSlaveAgentProtocol()

Method Detail

setHub

@Inject
public void setHub(NioChannelSelector hub)

isOptIn

public boolean isOptIn()

Allow experimental AgentProtocol implementations to declare being opt-in. Note that Jenkins.setAgentProtocols(Set) only records the protocols where the admin has made a conscious decision thus:

• if a protocol is opt-in, it records the admin enabling it
• if a protocol is opt-out, it records the admin disabling it

Implementations should not transition rapidly from opt-in -> opt-out -> opt-in. Implementations should never flip-flop: opt-in -> opt-out -> opt-in -> opt-out as that will basically clear any preference that an admin has set. This latter restriction should be ok as we only ever will be adding new protocols and retiring old ones.

Overrides:

isOptIn in class AgentProtocol

Returns:

true if the protocol requires explicit opt-in.

See Also:

Jenkins.setAgentProtocols(Set)

isDeprecated

public boolean isDeprecated()

Description copied from class: AgentProtocol

Checks if the protocol is deprecated.

Overrides:

isDeprecated in class AgentProtocol

getName

public String getName()

Description copied from class: AgentProtocol

Protocol name. This is a short string that consists of printable ASCII chars. Sent by the client to select the protocol.

Specified by:

getName in class AgentProtocol

Returns:

null to be disabled. This is useful for avoiding getting used until the protocol is properly configured.

getDisplayName

public String getDisplayName()

Returns the human readable protocol display name.

Overrides:

getDisplayName in class AgentProtocol

Returns:

the human readable protocol display name.

handle

public void handle(Socket socket)
            throws IOException,
                   InterruptedException

Description copied from class: AgentProtocol

Called by the connection handling thread to execute the protocol.

Specified by:

handle in class AgentProtocol

Throws:

IOException

InterruptedException