infoservice.dynamic
Class DynamicNetworkingHelper

java.lang.Object
  infoservice.dynamic.DynamicNetworkingHelper

public class DynamicNetworkingHelper
extends java.lang.Object

Constructor Summary

DynamicNetworkingHelper()

Method Summary

private org.w3c.dom.Document	constructAnswer(java.lang.String a_response) Constructs the answer for a connectivity request.
private java.lang.String	doPing(java.net.InetAddress a_Address, int a_port, long a_echoRequest) Actually executes the ping-like connectivity-test.
private int	extractPort(byte[] a_postData) Extracts the port from the POST data.
private boolean	isReachable(java.net.InetAddress a_Address, int a_port)
HttpResponseStructure	lastMixPostDynaCascade(byte[] a_postData) This method gets called when a last mix posts its cascade information to the InfoService Such a cascade is not yet established, so it is a temporary cascade an will be treated as such
HttpResponseStructure	mixPostConnectivityTest(java.net.InetAddress a_sourceAddress, byte[] a_postData) This method gets called when a mix asks the InfoService to verify its connectivity.

Methods inherited from class java.lang.Object

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

Constructor Detail

DynamicNetworkingHelper

public DynamicNetworkingHelper()

Method Detail

lastMixPostDynaCascade

public HttpResponseStructure lastMixPostDynaCascade(byte[] a_postData)

This method gets called when a last mix posts its cascade information to the InfoService Such a cascade is not yet established, so it is a temporary cascade an will be treated as such

Parameters:

a_postData - The data of the POST request

Returns:

HttpResponseStructure HTTP_RETURN_OK (no payload) or HTTP_RETURN_INTERNAL_SERVER_ERROR

mixPostConnectivityTest

public HttpResponseStructure mixPostConnectivityTest(java.net.InetAddress a_sourceAddress,
                                                     byte[] a_postData)

This method gets called when a mix asks the InfoService to verify its connectivity. Connectivity verification works as follows

• Mix sends /connectivity-request as HTTP-Post containing a XML structure with the port to be probed
• The InfoService opens a socket to the source address of the request to the requested port
• It then sends a random number as echo request (cp. ICMP echo request) to the mix
• The mix sends the payload (i.e. random number back over the socket
• InfoService responds with "OK" if it got the random number back, "Failed" otherwise

Parameters:

a_sourceAddress - The source address of the request

a_postData - The POST data containing a XML structure with the port

Returns:

HttpResponseStructure HTTP_RETURN_OK (containing the answer XML structure) or HTTP_RETURN_INTERNAL_SERVER_ERROR

constructAnswer

private org.w3c.dom.Document constructAnswer(java.lang.String a_response)

Constructs the answer for a connectivity request. It is an XML structure of the following type:

Parameters:

a_response -

Returns:

isReachable

private boolean isReachable(java.net.InetAddress a_Address,
                            int a_port)

doPing

private java.lang.String doPing(java.net.InetAddress a_Address,
                                int a_port,
                                long a_echoRequest)

Actually executes the ping-like connectivity-test. Sends a echoRequest to the querying mix and waits for the same token to come back from the mix

Parameters:

a_Address - The target address

a_port - The target port

a_echoRequest - The echoRequest to send

Returns:

The echoResponse from the mix

extractPort

private int extractPort(byte[] a_postData)

Extracts the port from the POST data. Creates a XML-Document and returns the value of the Port element.

Parameters:

a_postData - The POST data to parse

Returns:

The port or -1 if there was an error