fix(metering): Catch exceptions when retrieving network interface (fixes #41) (#43)

For example if properties are unsupported due to disabled IPv6

Author: GermanCoding

src/SyncTrayzor/Services/Metering/NetworkCostManager.cs

@@ -48,16 +48,24 @@ await Task.Run(async () =>
 
         private async Task<bool> IsConnectionMeteredUnsafe(IPAddress address)
         {
-            var profile = await NetworkUtils.GetNetworkProfileForIpAddress(address);
-            if (profile == null)
+            try
             {
+                var profile = await NetworkUtils.GetNetworkProfileForIpAddress(address);
+                if (profile == null)
+                {
+                    return false;
+                }
+
+                var cost = profile.GetConnectionCost();
+                // A network is "metered" if it is not unrestricted or unknown:
+                return cost.NetworkCostType != NetworkCostType.Unrestricted &&
+                       cost.NetworkCostType != NetworkCostType.Unknown;
+            }
+            catch (Exception exception)
+            {
+                Logger.Warn(exception, $"Unable to retrieve network profile for IP {address}");
                 return false;
             }
-
-            var cost = profile.GetConnectionCost();
-            // A network is "metered" if it is not unrestricted or unknown:
-            return cost.NetworkCostType != NetworkCostType.Unrestricted &&
-                   cost.NetworkCostType != NetworkCostType.Unknown;
         }
 
         private void NetworkStatusChanged(object sender)

src/SyncTrayzor/Services/Metering/NetworkUtils.cs

@@ -106,24 +106,31 @@ public static NetworkInterface GetBestNetworkInterface(IPAddress remoteAddress)
         foreach (NetworkInterface networkInterface in NetworkInterface.GetAllNetworkInterfaces())
         {
             var ipProperties = networkInterface.GetIPProperties();
-            switch (remoteAddress.AddressFamily)
+            try
             {
-                case AddressFamily.InterNetwork:
-                    if (ipProperties.GetIPv4Properties().Index == interfaceIndex)
-                    {
-                        return networkInterface;
-                    }
-
-                    break;
-                case AddressFamily.InterNetworkV6:
-                    if (ipProperties.GetIPv6Properties().Index == interfaceIndex)
-                    {
-                        return networkInterface;
-                    }
-
-                    break;
-                default:
-                    throw new ArgumentOutOfRangeException(nameof(remoteAddress));
+                switch (remoteAddress.AddressFamily)
+                {
+                    case AddressFamily.InterNetwork:
+                        if (ipProperties.GetIPv4Properties().Index == interfaceIndex)
+                        {
+                            return networkInterface;
+                        }
+
+                        break;
+                    case AddressFamily.InterNetworkV6:
+                        if (ipProperties.GetIPv6Properties().Index == interfaceIndex)
+                        {
+                            return networkInterface;
+                        }
+
+                        break;
+                    default:
+                        throw new ArgumentOutOfRangeException(nameof(remoteAddress));
+                }
+            }
+            catch (NetworkInformationException)
+            {
+                // Interface does not support the IP address, ignore
             }
         }
 
@@ -133,6 +140,7 @@ public static NetworkInterface GetBestNetworkInterface(IPAddress remoteAddress)
     public static async Task<ConnectionProfile?> GetNetworkProfileForIpAddress(IPAddress remoteAddress)
     {
         var networkInterface = GetBestNetworkInterface(remoteAddress);
+
         var networkInterfaceGuid = Guid.Parse(networkInterface.Id);
         var adapters = NetworkInformation.GetConnectionProfiles()
             .Select(existingProfile => existingProfile.NetworkAdapter).Distinct();