Send DLNA devices message to only the matched interface

This will be the right way for multiple interfaces, or the client will
receive all devices message with different IP addresses and could not
detect which one could access.

And provide one option DlnaOptions.SendOnlyMatchedHost to fallback to old
behaviour if this commit missed something.

1 files changed, 7 insertions, 6 deletions

diff --git a/RSSDP/SsdpCommunicationsServer.cs b/RSSDP/SsdpCommunicationsServer.cs
index 9da906b49..ea4d79c99 100644
--- a/RSSDP/SsdpCommunicationsServer.cs
+++ b/RSSDP/SsdpCommunicationsServer.cs
@@ -240,15 +240,15 @@ namespace Rssdp.Infrastructure
             }
         }
 
-        public Task SendMulticastMessage(string message, CancellationToken cancellationToken)
+        public Task SendMulticastMessage(string message, IpAddressInfo fromLocalIpAddress, CancellationToken cancellationToken)
         {
-            return SendMulticastMessage(message, SsdpConstants.UdpResendCount, cancellationToken);
+            return SendMulticastMessage(message, SsdpConstants.UdpResendCount, fromLocalIpAddress, cancellationToken);
         }
 
         /// <summary>
         /// Sends a message to the SSDP multicast address and port.
         /// </summary>
-        public async Task SendMulticastMessage(string message, int sendCount, CancellationToken cancellationToken)
+        public async Task SendMulticastMessage(string message, int sendCount, IpAddressInfo fromLocalIpAddress, CancellationToken cancellationToken)
         {
             if (message == null) throw new ArgumentNullException(nameof(message));
 
@@ -268,7 +268,7 @@ namespace Rssdp.Infrastructure
                     IpAddress = new IpAddressInfo(SsdpConstants.MulticastLocalAdminAddress, IpAddressFamily.InterNetwork),
                     Port = SsdpConstants.MulticastPort
 
-                }, cancellationToken).ConfigureAwait(false);
+                }, fromLocalIpAddress, cancellationToken).ConfigureAwait(false);
 
                 await Task.Delay(100, cancellationToken).ConfigureAwait(false);
             }
@@ -336,14 +336,15 @@ namespace Rssdp.Infrastructure
 
         #region Private Methods
 
-        private Task SendMessageIfSocketNotDisposed(byte[] messageData, IpEndPointInfo destination, CancellationToken cancellationToken)
+        private Task SendMessageIfSocketNotDisposed(byte[] messageData, IpEndPointInfo destination, IpAddressInfo fromLocalIpAddress, CancellationToken cancellationToken)
         {
             var sockets = _sendSockets;
             if (sockets != null)
             {
                 sockets = sockets.ToList();
 
-                var tasks = sockets.Select(s => SendFromSocket(s, messageData, destination, cancellationToken));
+                var tasks = sockets.Where(s => (fromLocalIpAddress == null || fromLocalIpAddress.Equals(s.LocalIPAddress)))
+                    .Select(s => SendFromSocket(s, messageData, destination, cancellationToken));
                 return Task.WhenAll(tasks);
             }