private BroadcastMessage deserialize(byte[] buf)
{
MemoryStream ms = new MemoryStream(buf);
BroadcastMessage message = null;
#if GENERIC_SERIALIZATION
try {
SerializedPacket p = new SerializedPacket(ms);
message = (BroadcastMessage)PacketTypes.DecodeMessage(null, p);
} catch (Exception e) {
Trace.WriteLine(e.ToString(), this.GetType().ToString());
return(null);
}
#else
BinaryFormatter bf = new BinaryFormatter();
try {
message = (BroadcastMessage)bf.Deserialize(ms);
} catch (SerializationException se) {
Trace.WriteLine("Failed to deserialize a BroadcastMessage: " + se.Message, this.GetType().ToString());
return(null);
} catch (Exception e) {
Trace.WriteLine(e.ToString(), this.GetType().ToString());
return(null);
}
#endif
return(message);
}
private void ReceiveCallback(IAsyncResult ar)
{
UdpClient u = (UdpClient)ar.AsyncState;
byte[] receiveBuf = null;
IPEndPoint remoteEP = null;
try {
receiveBuf = u.EndReceive(ar, ref remoteEP);
}
catch (ObjectDisposedException ode) {
Trace.WriteLine("ReceiveCallback: " + ode.Message, this.GetType().ToString());
}
catch (Exception e) {
Trace.WriteLine("ReceiveCallback exception: " + e.ToString(), this.GetType().ToString());
}
finally {
m_MessageReceived.Set(); //Let the listen thread continue.
}
if (receiveBuf != null)
{
BroadcastMessage message = deserialize(receiveBuf);
if (message != null)
{
if (message.SenderID != m_LocalSenderID)
{
processMessage(message, DateTime.Now);
}
}
}
}
/// <summary>
/// Update the broadcast message
/// </summary>
private void UpdateMessage()
{
lock (m_BufferSyncObject) {
BroadcastMessage message = new BroadcastMessage(m_ServerEP, m_ParticipantName, m_ServerID, m_PresentationName, m_showIP);
m_MessageBuffer = Serialize(message, out m_MessageBufferLength);
}
}
/// <summary>
/// Update the broadcast message
/// </summary>
private void UpdateMessage()
{
lock (m_BufferSyncObject) {
BroadcastMessage message = new BroadcastMessage(m_ServerEP, m_ParticipantName, m_ServerID, m_PresentationName, m_showIP);
m_MessageBuffer = Serialize(message, out m_MessageBufferLength);
}
}
/// <summary>
/// Handle one inbound BroadcastMessage
/// </summary>
/// <param name="message"></param>
/// <param name="timestamp"></param>
private void processMessage(BroadcastMessage message, DateTime timestamp)
{
//List<InstructorAdvertisement> nonLocalPublicSubnets = new List<InstructorAdvertisement>();
foreach (IPEndPoint ep in message.EndPoints) {
InstructorAdvertisement ia = new InstructorAdvertisement(ep, message.HumanName, message.PresentationName, message.SenderID, message.ShowIP);
using(Synchronizer.Lock(this.SyncRoot)) {
if (m_InstructorAdvertisements.Contains(ia)) { //We already have the entry, just update the timestamp.
int index = m_InstructorAdvertisements.IndexOf(ia);
m_InstructorAdvertisements[index].Timestamp = DateTime.Now;
continue;
}
if (ep.AddressFamily.Equals(AddressFamily.InterNetwork)) { //IPv4
if (!isPrivateSubnet(ep.Address)) {
//If there are both local and non-local public subnets, keep only the local ones (plus multicast)
if (matchesAnyLocalSubnet(ep.Address)) {
Trace.WriteLine("Adding Instructor Table Entry: " + ia.ToString(), this.GetType().ToString());
m_InstructorAdvertisements.Add(ia); //Not a private subnet, add to the table.
}
else if (isMulticastAddress(ep.Address)) {
Trace.WriteLine("Adding Instructor Table Entry: " + ia.ToString(), this.GetType().ToString());
ia.Multicast = true;
m_InstructorAdvertisements.Add(ia); //Not a private subnet, add to the table.
}
else {
//nonLocalPublicSubnets.Add(ia);
}
}
else {
//If it is a private subnet, the listener also needs to be on that subnet
//In effect, we can't talk to NAT'ed hosts directly unless we are also on the same NAT'ed network.
//Otherwise, we would have to connect to a port forwarding router.
if (matchesAnyLocalSubnet(ep.Address)) {
Trace.WriteLine("Adding Instructor Table Entry: " + ia.ToString(), this.GetType().ToString());
m_InstructorAdvertisements.Add(ia);
}
}
}
else if (ep.AddressFamily.Equals(AddressFamily.InterNetworkV6)) {
if (BroadcastManager.UseIPv6) {
//Don't show any IPv6 entries unless IPv6 is enabled on the local system.
//TODO: To correctly handle link local and site local, we need to do a bit more work here.
Trace.WriteLine("Adding Instructor Table Entry: " + ia.ToString(), this.GetType().ToString());
m_InstructorAdvertisements.Add(ia);
}
}
}
}
//Are there cases were we would want to show the non-local public subnet addresses?
}
/// <summary>
/// Handle one inbound BroadcastMessage
/// </summary>
/// <param name="message"></param>
/// <param name="timestamp"></param>
private void processMessage(BroadcastMessage message, DateTime timestamp)
{
//List<InstructorAdvertisement> nonLocalPublicSubnets = new List<InstructorAdvertisement>();
foreach (IPEndPoint ep in message.EndPoints)
{
InstructorAdvertisement ia = new InstructorAdvertisement(ep, message.HumanName, message.PresentationName, message.SenderID, message.ShowIP);
using (Synchronizer.Lock(this.SyncRoot)) {
if (m_InstructorAdvertisements.Contains(ia)) //We already have the entry, just update the timestamp.
{
int index = m_InstructorAdvertisements.IndexOf(ia);
m_InstructorAdvertisements[index].Timestamp = DateTime.Now;
continue;
}
if (ep.AddressFamily.Equals(AddressFamily.InterNetwork)) //IPv4
{
if (!isPrivateSubnet(ep.Address))
{
//If there are both local and non-local public subnets, keep only the local ones (plus multicast)
if (matchesAnyLocalSubnet(ep.Address))
{
Trace.WriteLine("Adding Instructor Table Entry: " + ia.ToString(), this.GetType().ToString());
m_InstructorAdvertisements.Add(ia); //Not a private subnet, add to the table.
}
else if (isMulticastAddress(ep.Address))
{
Trace.WriteLine("Adding Instructor Table Entry: " + ia.ToString(), this.GetType().ToString());
ia.Multicast = true;
m_InstructorAdvertisements.Add(ia); //Not a private subnet, add to the table.
}
else
{
//nonLocalPublicSubnets.Add(ia);
}
}
else
{
//If it is a private subnet, the listener also needs to be on that subnet
//In effect, we can't talk to NAT'ed hosts directly unless we are also on the same NAT'ed network.
//Otherwise, we would have to connect to a port forwarding router.
if (matchesAnyLocalSubnet(ep.Address))
{
Trace.WriteLine("Adding Instructor Table Entry: " + ia.ToString(), this.GetType().ToString());
m_InstructorAdvertisements.Add(ia);
}
}
}
else if (ep.AddressFamily.Equals(AddressFamily.InterNetworkV6))
{
if (BroadcastManager.UseIPv6)
{
//Don't show any IPv6 entries unless IPv6 is enabled on the local system.
//TODO: To correctly handle link local and site local, we need to do a bit more work here.
Trace.WriteLine("Adding Instructor Table Entry: " + ia.ToString(), this.GetType().ToString());
m_InstructorAdvertisements.Add(ia);
}
}
}
}
//Are there cases were we would want to show the non-local public subnet addresses?
}