private void retriveDb()
{
if (!Directory.Exists(DB_PATH))
{
Directory.CreateDirectory(DB_PATH);
}
if (File.Exists(DB_FILE))
{
String[] lines = File.ReadAllLines(DB_FILE);
foreach (String line in lines)
{
try
{
IpPoolItem item = IpPoolItem.valueOf(line);
item.status = IpPoolItem.Status.ACKED;
lease.Add(item.mac, item);
}
catch
{
Util.log("retrieve dhcp data fail: " + line);
}
}
Util.log("retrieve dhcp data, count " + lease.Count);
}
else
{
Util.log("no dhcp data file");
File.WriteAllText(DB_FILE, "");
}
}
public static IpPoolItem valueOf(String s)
{
String[] ss = s.Split(';');
IpPoolItem item = new IpPoolItem(ss[0], IPAddress.Parse(ss[1]), long.Parse(ss[2]));
return(item);
}
public IpPoolItem getPoolItem(String mac)
{
IpPoolItem item = null;
if (!lease.TryGetValue(mac, out item))
{
return(null);
}
return(item);
}
public IPAddress ackIP(String mac)
{
IpPoolItem item = null;
if (!lease.TryGetValue(mac, out item)) //already allocate address for this mac
{
return(null);
}
item.status = IpPoolItem.Status.ACKED;
return(item.ip);
}
public void release(String mac)
{
IpPoolItem item = null;
if (lease.TryGetValue(mac, out item))
{
lease.Remove(mac);
item.clearTick();
item.mac = null;
item.status = IpPoolItem.Status.NULL;
released.Enqueue(item);
//storeDb();
}
}
static void requestHandler(DHCPRequest dhcpRequest)
{
String mac = Util.bytesToMac(dhcpRequest.GetChaddr());
IPAddress si = new IPAddress(dhcpRequest.GetOptionData(DHCPOption.ServerIdentifier));
if (si != null && si.Equals(localAddress)) //client select this server
{
IPAddress requestIp = new IPAddress(dhcpRequest.GetOptionData(DHCPOption.RequestedIPAddress));
IPAddress ip = pool.ackIP(mac);
if (ip != null)
{
pool.storeDb();
dhcpRequest.SendDHCPReply(DHCPMsgType.DHCPACK, ip, defaultOptions);
sendNotify(DhcpNotify.NotifyType.REQUEST, String.Format("RTDhcpServer receives DHCP request message from {0}, ack {1}", mac, ip));
}
/*
* IPAddress ip = pool.getIP(mac);
* if (requestIp!=null && ip.Equals(requestIp))
* {
* pool.storeDb();
* dhcpRequest.SendDHCPReply(DHCPMsgType.DHCPACK, ip, options);
* sendNotify(DhcpNotify.NotifyType.REQUEST, String.Format("RTDhcpServer receives DHCP request message from {0}, ack {1}", mac, ip));
* } else
* {
* dhcpRequest.SendDHCPReply(DHCPMsgType.DHCPNAK, requestIp, options);
* pool.release(mac);
* sendNotify(DhcpNotify.NotifyType.REQUEST, String.Format("RTDhcpServer receives DHCP request message from {0}, nack {1}", mac, requestIp));
* }
*/
}
else
{
IpPoolItem item = pool.getPoolItem(mac);
if (item != null && item.status == IpPoolItem.Status.ACKED) //reuse previous allocated address
{
IPAddress ip = item.ip;
pool.storeDb();
dhcpRequest.SendDHCPReply(DHCPMsgType.DHCPACK, ip, defaultOptions);
sendNotify(DhcpNotify.NotifyType.REQUEST, String.Format("RTDhcpServer receives DHCP request(reuse) message from {0}, ack {1}", mac, ip));
}
else //not selected by client
{
pool.release(mac);
sendNotify(DhcpNotify.NotifyType.REQUEST, String.Format("RTDhcpServer receives DHCP request message from {0}, not selected by this client", mac));
}
}
}
public IPAddress offerIP(String mac, IPAddress preferIp)
{
IpPoolItem item = null;
if (!lease.TryGetValue(mac, out item)) //already allocate address for this mac
{
if (preferIp != null)
{
if (!containsIp(preferIp))
{
item = new IpPoolItem(preferIp);
}
}
if (item == null && released.Count > 0) //is there released address to be reused
{
lock (released)
{
item = released.Dequeue();
}
}
if (item == null) //find an available address
{
IPAddress ip = null;
ip = getAvailableAddress();
item = new IpPoolItem(ip);
}
item.mac = mac;
item.setTick();
item.status = IpPoolItem.Status.OFFERED;
lease[mac] = item;
//storeDb();
}
return(item.ip);
}