private void TryFireArpReplyReceied(Common.IPv4Address ip, Common.MacAddress mac)
{
try
{
ArpReplyReceived(ip, mac);
}
catch
{
}
}
public Common.MacAddress ResolveIP(Common.IPv4Address ip)
{
// Do we already know?
if (ArpCache.ContainsKey(ip.AsString) && (ArpCache[ip.AsString].Expiration > DateTime.Now || ArpCache[ip.AsString].Type == ArpEntryType.Static))
{
Common.MacAddress mac = ArpCache[ip.AsString].Mac;
if (DisableCache)
{
ArpCache.Clear();
}
return(mac);
}
// Is this the broadcast IP for our network?
if (ip.AsString == _client.Configuration.BroadcastAddress.AsString)
{
return(Common.MacAddress.Broadcast);
}
// Is this me?
if (ip.AsString == _client.Configuration.IpAddress.AsString)
{
return(_client.Configuration.MacAddress);
}
// Is this IP in our subnet?
if (!Common.IPv4Address.IsInSameSubnet(ip, _client.Configuration.IpAddress, _client.Configuration.SubnetMask))
{
return(ResolveIP(_client.Configuration.DefaultGateway));
}
// We don't know. Send packet and wait for response.
SendArpResolutionPacket(ip);
DateTime now = DateTime.Now;
while ((DateTime.Now - now).TotalSeconds < TIMEOUT)
{
if (ArpCache.ContainsKey(ip.AsString) && (ArpCache[ip.AsString].Expiration > DateTime.Now || ArpCache[ip.AsString].Type == ArpEntryType.Static))
{
Common.MacAddress mac = ArpCache[ip.AsString].Mac;
if (DisableCache)
{
ArpCache.Clear();
}
}
System.Threading.Thread.Sleep(100);
}
if (ArpCache.ContainsKey(ip.AsString))
{
return(ArpCache[ip.AsString].Mac);
}
throw new IpResolutionFailed(ip);
}
public void AddStaticEntry(Common.IPv4Address ip, Common.MacAddress mac)
{
ArpCacheEntry entry = new ArpCacheEntry()
{
Ip = ip,
Mac = mac,
Expiration = DateTime.Now,
Type = ArpEntryType.Static,
};
if (ArpCache.ContainsKey(ip.AsString))
{
ArpCache[ip.AsString] = entry;
}
else
{
ArpCache.AddOrUpdate(ip.AsString, entry, null);
}
TryFireArpCacheChanged();
}
public override void OnReceivePacket(Common.PacketData pdata)
{
var packet = pdata.Packet;
var arp = packet.Ethernet.Arp;
var senderMac = new Common.MacAddress(arp.SenderHardwareAddress.ToArray());
var destMac = new Common.MacAddress(arp.TargetHardwareAddress.ToArray());
var senderIp = new Common.IPv4Address(arp.SenderProtocolAddress.ToArray());
var destIp = new Common.IPv4Address(arp.TargetProtocolAddress.ToArray());
// We can cache their MAC and IP
if (AcceptGratuitousReplies || destMac.AsString != Common.MacAddress.Broadcast.AsString)
{
ArpCache.AddOrUpdate(senderIp.AsString, new ArpCacheEntry()
{
Mac = senderMac,
Ip = senderIp,
Type = ArpEntryType.Dynamic,
Expiration = GetNextExpirationTime(),
}, (str, myarp) => myarp);
if (arp.Operation == ArpOperation.Reply)
{
TryFireArpReplyReceied(senderIp, senderMac);
}
// Fire the Cache Changed event
TryFireArpCacheChanged();
}
// If it is a request for our IP, respond
if (arp.Operation == ArpOperation.Request && destIp.AsString == _client.Configuration.IpAddress.AsString)
{
// Send Reply Packet
SendArpReplyPacket(senderIp);
}
}