sipprocessor.cpp

a open source project in linux for peer to peer on seep

#include "SipProcessor.h"
#include "Database.h"
#include "time.h"
#include <sstream>
using namespace std;

// Init static members
const string SipProcessor::INVITE = "INVITE";
const string SipProcessor::REGISTER = "REGISTER";
const string SipProcessor::ACK = "ACK";
const string SipProcessor::SIP_HEADER_OK = "SIP/2.0 200 OK";
const string SipProcessor::SIP_HEADER_TRYING = "SIP/2.0 100 Trying";
const string SipProcessor::SIP_HEADER_MOVED_TEMPORARILY = "SIP/2.0 302 Moved Temporarily";
//const string SipProcessor::SIP_HEADER_MOVED_TEMPORARILY = "SIP/2.0 305 Use Proxy";

// Constructor
SipProcessor::SipProcessor(UDPServerSocket* sSocket, IPAddress* callerIP, int cPort) {
	log = new Logger("SipProcessor");
	serverSocket = sSocket;
	callerIPSource = callerIP;
	callerPort = cPort;
}

// Destructor
SipProcessor::~SipProcessor() {
}

// Processes a SIP request.
void SipProcessor::processRequest(const string& request) {
	originalRequest = request;
	log->debug("Request received.");
	
	istringstream is;
	is.str(request);
	string line;
	getline(is, line);
	if (line.find(REGISTER) == 0) {
		processRegister();
	} else if (line.find(INVITE) == 0) {
		processInvite();
	} else if (line.find(ACK) == 0) {
		processAck();
	} else {
		sendRequestNotSupported();
	}
}


// Private methods

void SipProcessor::processRegister() {
	log->debug("Entering processRegister...");
	
	istringstream is(originalRequest);
	ostringstream responseStream;
	string line;
	
	responseStream << SIP_HEADER_OK << endl;
	
	string contactLine;
	
	// Copy needed lines from request to response
	for (getline(is, line); line != ""; getline(is, line)) {
		if (line.find("Via:") == 0) {
			responseStream << line << endl;
		} else if (line.find("To:") == 0) {
			responseStream << line << endl;
		} else if (line.find("From:") == 0) {
			responseStream << line << endl;
		} else if (line.find("Call-ID:") == 0) {
			responseStream << line << endl;
		} else if (line.find("CSeq:") == 0) {
			responseStream << line << endl;
			responseStream << "Date: " << getDateAndTime() << endl;
		} else if (line.find("Contact:") == 0) {
			responseStream << line << endl;
			contactLine = line;
		} else if (line.find("Content-Length:") == 0) {
			responseStream << line << endl << endl;
		} 
	}
	
	// Prepare contact data, will be needed by SipServer
	if (!splitContactData(contactLine)) {
		log->debug("Eror reading contact data from: " + contactLine);
		sendServerError();
		return;
	}
	
	// Everything ok -> send response to requestor
	string response = responseStream.str();
	log->debug("Sending REGISTER ok to requestor: + " + response);
	int bytesTransferred = serverSocket->SendDatagram(response.c_str(), response.size(), *callerIPSource, callerPort);
    log->debug(" - sent bytes: " , bytesTransferred);
	
	// Publish the values in the kademlia network
	log->debug("Publishing the user data in kademlia...");
	Database* db = Database::getInstance();
	string name = responseContact[0];
	string data = name + "@" + responseContact[1];
	if (responseContact[2] != "") {
		data += ":" + responseContact[2]; // if port is not default
	}
	int countPublished = db->put(name, data);
	if (countPublished < 1) {
		log->debug("ERROR: Could not publish: " + data);
	}
	log->debug("Processing REGISTER ok :)");
}

void SipProcessor::processInvite() {
	log->debug("Entering processInvite...");
	int bytesTransferred = 0;
	
	// First send trying
	string tryingMessage = createTryingMessage();
	log->debug("Sending TRYING to caller...");
	log->debug("Trying message:\n" + tryingMessage);
	bytesTransferred = serverSocket->SendDatagram(tryingMessage.c_str(), tryingMessage.size(), *callerIPSource, callerPort);
	log->debug(" - sent bytes: " , bytesTransferred);
	
	
	// Prepare invite request with data from kademlia
	string inviteRequest = prepareInvite();
	
	if (inviteRequest == "") {
		// "" indicates error
		// Error processing is done in prepareInvite() so we just return.
		return;
	}
	
	// Get the destination where to forward the message
	string name = responseContact[0];
	string ip = responseContact[1];
	string port = responseContact[2];
	if (port == "") {
		port = "5060";	// Def SIP port
	}
	int remotePort = atoi(port.c_str());
	
	// Create the socket to callee
	calleeSocket = new UDPConnectedSocket (false);
	calleeIPSource = ip.c_str();
	log->debug("Creating socket to callee, IP=" + ip + ", port=", remotePort);
	calleeSocket->Connect(calleeIPSource, remotePort);

	// Forward INVITE to callee
	string tempIP(calleeSocket->RemoteIPAddress().GetAddressString());
	log->debug("Forwarding INVITE Message to: IP = " + tempIP + ", port = ", calleeSocket->RemotePortNumber());
	bytesTransferred = calleeSocket->SendDatagram(inviteRequest.c_str(), inviteRequest.size());
	log->debug(" - sent bytes: ", bytesTransferred);
	
	char response[BUFFER_SIZE];
	response[0] = 0;
	
	// Wait for TRYING
	log->debug("Waiting for TRYING message");
	bytesTransferred = calleeSocket->ReceiveDatagram(response, BUFFER_SIZE);
	log->debug(" - received bytes: ", bytesTransferred);
	string returnResponse(response);
	log->debug("Response:\n" + returnResponse);

	// Forward TRYING to original requestor
	//bytesTransferred = serverSocket->SendDatagram(returnResponse.c_str(), returnResponse.size(), *callerIPSource, callerPort);
	//log->debug("TRYING forwarded...");
	//log->debug(" - sent bytes: " , bytesTransferred);

	// Wait for RINGING
	log->debug("Waiting for RINGING message...");
	bytesTransferred = calleeSocket->ReceiveDatagram(response, BUFFER_SIZE);
	log->debug(" - received bytes: ", bytesTransferred);
	returnResponse = response;
	log->debug("Response:\n" + returnResponse);

	// Forward the RINGING to original requestor
	bytesTransferred = serverSocket->SendDatagram(returnResponse.c_str(), returnResponse.size(), *callerIPSource, callerPort);
	log->debug("RINGING forwarded...");
	log->debug(" - sent bytes: " , bytesTransferred);

	// Wait for OK
	log->debug("Waiting for OK message...");
	bytesTransferred = calleeSocket->ReceiveDatagram(response, BUFFER_SIZE);
	log->debug(" - received bytes: ", bytesTransferred);
	returnResponse = response;
	log->debug("Response:\n" + returnResponse);

	// FOrward the OK to original requestor
	bytesTransferred = serverSocket->SendDatagram(returnResponse.c_str(), returnResponse.size(), *callerIPSource, callerPort);
	log->debug("OK forwarded...");
	log->debug(" - sent bytes: " , bytesTransferred);

	/*	
	// Wait for ACK from original requesor
	log->debug("Waiting for ACK message...");
	bytesTransferred = serverSocket->ReceiveDatagram(response, BUFFER_SIZE, *callerIPSource, callerPort);
	log->debug(" - received bytes: ", bytesTransferred);
	returnResponse = response;
	log->debug("Response:\n" + returnResponse);
	
	// Forward ACK to callee
	bytesTransferred = calleeSocket->SendDatagram(response, returnResponse.size());
	log->debug("ACK");
	log->debug(" - sent bytes: ", bytesTransferred);
	*/

	// Disconnect and release memory
	calleeSocket->DisConnect();
	delete calleeSocket;
	log->debug("Processing INVITE ok :))");
}

void SipProcessor::processAck() {
	log->debug("Entering processAck...");
	/*
	int bytesTransferred;
	
	istringstream is(originalRequest);
	string line;
	string contactLine;
	
	// Copy needed lines from request to response
	for (getline(is, line); line != ""; getline(is, line)) {
		if (line.find("To:") == 0) {
			if (!splitContactData(line)) {
				log->debug("Eror reading contact data from: " + contactLine);
				sendServerError();
				return;
			}
		} 
	}
	
	// Forward the ACK to the found address
	
	// Get the destination where to forward the message
	string name = responseContact[0];
	string ip = responseContact[1];
	string port = responseContact[2];
	if (port == "") {
		port = "5060";	// Def SIP port
	}
	int remotePort = atoi(port.c_str());
	
	// Create the socket to callee
	calleeSocket = new UDPConnectedSocket (false);
	calleeIPSource = ip.c_str();
	log->debug("Creating socket to callee, IP=" + ip + ", port=", remotePort);
	calleeSocket->Connect(calleeIPSource, remotePort);