/**
* Removes from the specified list of candidates providers connected to a registrar that does not
* match the IP address that we are receiving a request from.
*
* @param candidates the list of providers we've like to filter.
* @param request the request that we are currently dispatching
*/
private void filterByAddress(List<ProtocolProviderServiceSipImpl> candidates, Request request) {
Iterator<ProtocolProviderServiceSipImpl> iterPP = candidates.iterator();
while (iterPP.hasNext()) {
ProtocolProviderServiceSipImpl candidate = iterPP.next();
if (candidate.getRegistrarConnection() == null) {
// RegistrarLess connections are ok
continue;
}
if (!candidate.getRegistrarConnection().isRegistrarless()
&& !candidate.getRegistrarConnection().isRequestFromSameConnection(request)) {
iterPP.remove();
}
}
}
/**
* Find the <tt>ProtocolProviderServiceSipImpl</tt> (one of our "candidate recipient" listeners)
* which this <tt>request</tt> should be dispatched to. The strategy is to look first at the
* request URI, and then at the To field to find a matching candidate for dispatching. Note that
* this method takes a <tt>Request</tt> as param, and not a <tt>ServerTransaction</tt>, because
* sometimes <tt>RequestEvent</tt>s have no associated <tt>ServerTransaction</tt>.
*
* @param request the <tt>Request</tt> to find a recipient for.
* @return a suitable <tt>ProtocolProviderServiceSipImpl</tt>.
*/
private ProtocolProviderServiceSipImpl findTargetFor(Request request) {
if (request == null) {
logger.error("request shouldn't be null.");
return null;
}
List<ProtocolProviderServiceSipImpl> currentListenersCopy =
new ArrayList<ProtocolProviderServiceSipImpl>(this.getSipListeners());
// Let's first narrow down candidate choice by comparing
// addresses and ports (no point in delivering to a provider with a
// non matching IP address since they will reject it anyway).
filterByAddress(currentListenersCopy, request);
if (currentListenersCopy.size() == 0) {
logger.error("no listeners");
return null;
}
URI requestURI = request.getRequestURI();
if (requestURI.isSipURI()) {
String requestUser = ((SipURI) requestURI).getUser();
List<ProtocolProviderServiceSipImpl> candidates =
new ArrayList<ProtocolProviderServiceSipImpl>();
// check if the Request-URI username is
// one of ours usernames
for (ProtocolProviderServiceSipImpl listener : currentListenersCopy) {
String ourUserID = listener.getAccountID().getUserID();
// logger.trace(ourUserID + " *** " + requestUser);
if (ourUserID.equals(requestUser)) {
if (logger.isTraceEnabled())
logger.trace("suitable candidate found: " + listener.getAccountID());
candidates.add(listener);
}
}
// the perfect match
// every other case is approximation
if (candidates.size() == 1) {
ProtocolProviderServiceSipImpl perfectMatch = candidates.get(0);
if (logger.isTraceEnabled())
logger.trace("Will dispatch to \"" + perfectMatch.getAccountID() + "\"");
return perfectMatch;
}
// more than one account match
if (candidates.size() > 1) {
// check if a custom param exists in the contact
// address (set for registrar accounts)
for (ProtocolProviderServiceSipImpl candidate : candidates) {
String hostValue =
((SipURI) requestURI).getParameter(SipStackSharing.CONTACT_ADDRESS_CUSTOM_PARAM_NAME);
if (hostValue == null) continue;
if (hostValue.equals(candidate.getContactAddressCustomParamValue())) {
if (logger.isTraceEnabled())
logger.trace(
"Will dispatch to \""
+ candidate.getAccountID()
+ "\" because "
+ "\" the custom param was set");
return candidate;
}
}
// Past this point, our guess is not reliable. We try to find
// the "least worst" match based on parameters like the To field
// check if the To header field host part
// matches any of our SIP hosts
for (ProtocolProviderServiceSipImpl candidate : candidates) {
URI fromURI = ((FromHeader) request.getHeader(FromHeader.NAME)).getAddress().getURI();
if (fromURI.isSipURI() == false) continue;
SipURI ourURI = (SipURI) candidate.getOurSipAddress((SipURI) fromURI).getURI();
String ourHost = ourURI.getHost();
URI toURI = ((ToHeader) request.getHeader(ToHeader.NAME)).getAddress().getURI();
if (toURI.isSipURI() == false) continue;
String toHost = ((SipURI) toURI).getHost();
// logger.trace(toHost + "***" + ourHost);
if (toHost.equals(ourHost)) {
if (logger.isTraceEnabled())
logger.trace(
"Will dispatch to \""
+ candidate.getAccountID()
+ "\" because "
+ "host in the To: is the same as in our AOR");
return candidate;
}
}
// fallback on the first candidate
ProtocolProviderServiceSipImpl target = candidates.iterator().next();
logger.info(
"Will randomly dispatch to \""
+ target.getAccountID()
+ "\" because there is ambiguity on the username from"
+ " the Request-URI");
if (logger.isTraceEnabled()) logger.trace("\n" + request);
return target;
}
// fallback on any account
ProtocolProviderServiceSipImpl target = currentListenersCopy.iterator().next();
if (logger.isDebugEnabled())
logger.debug(
"Will randomly dispatch to \""
+ target.getAccountID()
+ "\" because the username in the Request-URI "
+ "is unknown or empty");
if (logger.isTraceEnabled()) logger.trace("\n" + request);
return target;
} else {
logger.error("Request-URI is not a SIP URI, dropping");
}
return null;
}