static void Request(DHCPRequest dhcpRequest)
{
var type = dhcpRequest.GetMsgType();
var mac = ByteArrayToString(dhcpRequest.GetChaddr());
// IP for client
IPAddress ip;
if (!leases.TryGetValue(mac, out ip))
{
ip = new IPAddress(new byte[] { 10, 0, 0, nextIP++ });
leases[mac] = ip;
}
Console.WriteLine(type.ToString() + " request from " + mac + ", it will be " + ip.ToString());
var options = dhcpRequest.GetAllOptions();
Console.Write("Options:");
foreach (DHCPOption option in options.Keys)
{
Console.WriteLine(option.ToString() + ": " + ByteArrayToString(options[option]));
}
// Lets show some request info
var requestedOptions = dhcpRequest.GetRequestedOptionsList();
if (requestedOptions != null)
{
Console.Write("Requested options:");
foreach (DHCPOption option in requestedOptions) Console.Write(" " + option.ToString());
Console.WriteLine();
}
// Option 82 info
var relayInfoN = dhcpRequest.GetRelayInfo();
if (relayInfoN != null)
{
var relayInfo = (RelayInfo)relayInfoN;
if (relayInfo.AgentCircuitID != null) Console.WriteLine("Relay agent circuit ID: " + ByteArrayToString(relayInfo.AgentCircuitID));
if (relayInfo.AgentRemoteID != null) Console.WriteLine("Relay agent remote ID: " + ByteArrayToString(relayInfo.AgentRemoteID));
}
Console.WriteLine();
var replyOptions = new DHCPReplyOptions();
// Options should be filled with valid data. Only requested options will be sent.
replyOptions.SubnetMask = IPAddress.Parse("255.255.255.0");
replyOptions.DomainName = "SharpDHCPServer";
replyOptions.ServerIdentifier = IPAddress.Parse("10.0.0.1");
replyOptions.RouterIP = IPAddress.Parse("10.0.0.1");
replyOptions.DomainNameServers = new IPAddress[] { IPAddress.Parse("192.168.100.2"), IPAddress.Parse("192.168.100.3") };
// Some static routes
replyOptions.StaticRoutes = new NetworkRoute[] {
new NetworkRoute(IPAddress.Parse("10.0.0.0"), IPAddress.Parse("255.0.0.0"), IPAddress.Parse("10.0.0.1")),
new NetworkRoute(IPAddress.Parse("192.168.0.0"), IPAddress.Parse("255.255.0.0"), IPAddress.Parse("10.0.0.1")),
new NetworkRoute(IPAddress.Parse("172.16.0.0"), IPAddress.Parse("255.240.0.0"), IPAddress.Parse("10.0.0.1")),
new NetworkRoute(IPAddress.Parse("80.252.130.248"), IPAddress.Parse("255.255.255.248"), IPAddress.Parse("10.0.0.1")),
new NetworkRoute(IPAddress.Parse("80.252.128.88"), IPAddress.Parse("255.255.255.248"), IPAddress.Parse("10.0.0.1")),
};
// Lets send reply to client!
if (type == DHCPMsgType.DHCPDISCOVER)
dhcpRequest.SendDHCPReply(DHCPMsgType.DHCPOFFER, ip, replyOptions);
if (type == DHCPMsgType.DHCPREQUEST)
dhcpRequest.SendDHCPReply(DHCPMsgType.DHCPACK, ip, replyOptions);
}
/// <summary>
/// Sends DHCP reply
/// </summary>
/// <param name="msgType">Type of DHCP message to send</param>
/// <param name="ip">IP for client</param>
/// <param name="replyData">Reply options (will be sent if requested)</param>
/// <param name="otherForceOptions">Force reply options (will be sent anyway)</param>
public void SendDHCPReply(DHCPMsgType msgType, IPAddress ip, DHCPReplyOptions replyData, Dictionary<DHCPOption, byte[]> otherForceOptions)
{
var replyBuffer = requestData;
replyBuffer.op = 2; // Reply
replyBuffer.yiaddr = ip.GetAddressBytes(); // Client's IP
replyBuffer.options = CreateOptionStruct(msgType, replyData, otherForceOptions); // Options
if (!string.IsNullOrEmpty(dhcpServer.ServerName))
{
var serverNameBytes = Encoding.ASCII.GetBytes(dhcpServer.ServerName);
int len = (serverNameBytes.Length > 63) ? 63 : serverNameBytes.Length;
Array.Copy(serverNameBytes, replyBuffer.sname, len);
replyBuffer.sname[len] = 0;
}
lock (requestSocket)
{
IPEndPoint endPoint;
if ((replyBuffer.giaddr[0] == 0) && (replyBuffer.giaddr[1] == 0) &&
(replyBuffer.giaddr[2] == 0) && (replyBuffer.giaddr[3] == 0))
{
requestSocket.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.Broadcast, true);
endPoint = new IPEndPoint(IPAddress.Broadcast, PORT_TO_SEND_TO_CLIENT);
}
else
{
requestSocket.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.Broadcast, false);
endPoint = new IPEndPoint(new IPAddress(replyBuffer.giaddr), PORT_TO_SEND_TO_RELAY);
}
var DataToSend = BuildDataStructure(replyBuffer);
requestSocket.SendTo(DataToSend, endPoint);
}
}
/// <summary>
/// Sends DHCP reply
/// </summary>
/// <param name="msgType">Type of DHCP message to send</param>
/// <param name="ip">IP for client</param>
/// <param name="replyData">Reply options (will be sent if requested)</param>
public void SendDHCPReply(DHCPMsgType msgType, IPAddress ip, DHCPReplyOptions replyData)
{
SendDHCPReply(msgType, ip, replyData, null);
}
private byte[] CreateOptionStruct(DHCPMsgType msgType, DHCPReplyOptions replyOptions, Dictionary<DHCPOption, byte[]> otherForceOptions)
{
byte[] resultOptions = null;
// Requested options
var reqList = GetRequestedOptionsList();
// Option82?
var relayInfo = this.GetOptionData(DHCPOption.RelayInfo);
CreateOptionElement(ref resultOptions, DHCPOption.DHCPMessageTYPE, new byte[] { (byte)msgType });
// Server identifier - our IP address
if ((replyOptions != null) && (replyOptions.ServerIdentifier != null))
CreateOptionElement(ref resultOptions, DHCPOption.ServerIdentifier, replyOptions.ServerIdentifier.GetAddressBytes());
// Requested options
if ((reqList != null) && (replyOptions != null))
foreach (DHCPOption i in reqList)
{
byte[] optionData = null;
// If it's force option - ignore it. We'll send it later.
if ((otherForceOptions != null) && (otherForceOptions.TryGetValue(i, out optionData)))
continue;
switch (i)
{
case DHCPOption.SubnetMask:
if (replyOptions.SubnetMask != null)
optionData = replyOptions.SubnetMask.GetAddressBytes();
break;
case DHCPOption.Router:
if (replyOptions.RouterIP != null)
optionData = replyOptions.RouterIP.GetAddressBytes();
break;
case DHCPOption.DomainNameServers:
if (replyOptions.DomainNameServers != null)
{
optionData = new byte[] { };
foreach (var dns in replyOptions.DomainNameServers)
{
var dnsserv = dns.GetAddressBytes();
Array.Resize(ref optionData, optionData.Length + 4);
Array.Copy(dnsserv, 0, optionData, optionData.Length - 4, 4);
}
}
break;
case DHCPOption.DomainName:
if (!string.IsNullOrEmpty(replyOptions.DomainName))
optionData = System.Text.Encoding.ASCII.GetBytes(replyOptions.DomainName);
break;
case DHCPOption.ServerIdentifier:
if (replyOptions.ServerIdentifier != null)
optionData = replyOptions.ServerIdentifier.GetAddressBytes();
break;
case DHCPOption.LogServer:
if (replyOptions.LogServerIP != null)
optionData = replyOptions.LogServerIP.GetAddressBytes();
break;
case DHCPOption.StaticRoutes:
case DHCPOption.StaticRoutesWin:
if (replyOptions.StaticRoutes != null)
{
optionData = new byte[] { };
foreach (var route in replyOptions.StaticRoutes)
{
var routeData = route.BuildRouteData();
Array.Resize(ref optionData, optionData.Length + routeData.Length);
Array.Copy(routeData, 0, optionData, optionData.Length - routeData.Length, routeData.Length);
}
}
break;
default:
replyOptions.OtherRequestedOptions.TryGetValue(i, out optionData);
break;
}
if (optionData != null)
CreateOptionElement(ref resultOptions, i, optionData);
}
if (GetMsgType() != DHCPMsgType.DHCPINFORM)
{
// Lease time
if (replyOptions != null)
{
var leaseTime = new byte[4];
leaseTime[3] = (byte)(replyOptions.IPAddressLeaseTime);
leaseTime[2] = (byte)(replyOptions.IPAddressLeaseTime >> 8);
leaseTime[1] = (byte)(replyOptions.IPAddressLeaseTime >> 16);
leaseTime[0] = (byte)(replyOptions.IPAddressLeaseTime >> 24);
CreateOptionElement(ref resultOptions, DHCPOption.IPAddressLeaseTime, leaseTime);
leaseTime[3] = (byte)(replyOptions.RenewalTimeValue_T1);
leaseTime[2] = (byte)(replyOptions.RenewalTimeValue_T1 >> 8);
leaseTime[1] = (byte)(replyOptions.RenewalTimeValue_T1 >> 16);
leaseTime[0] = (byte)(replyOptions.RenewalTimeValue_T1 >> 24);
CreateOptionElement(ref resultOptions, DHCPOption.RenewalTimeValue_T1, leaseTime);
leaseTime[3] = (byte)(replyOptions.RebindingTimeValue_T2);
leaseTime[2] = (byte)(replyOptions.RebindingTimeValue_T2 >> 8);
leaseTime[1] = (byte)(replyOptions.RebindingTimeValue_T2 >> 16);
leaseTime[0] = (byte)(replyOptions.RebindingTimeValue_T2 >> 24);
CreateOptionElement(ref resultOptions, DHCPOption.RebindingTimeValue_T2, leaseTime);
}
}
// Other requested options
if (otherForceOptions != null)
foreach (var option in otherForceOptions.Keys)
{
CreateOptionElement(ref resultOptions, option, otherForceOptions[option]);
if (option == DHCPOption.RelayInfo) relayInfo = null;
}
// Option 82? Send it back!
if (relayInfo != null)
CreateOptionElement(ref resultOptions, DHCPOption.RelayInfo, relayInfo);
// Create the end option
Array.Resize(ref resultOptions, resultOptions.Length + 1);
Array.Copy(new byte[] { 255 }, 0, resultOptions, resultOptions.Length - 1, 1);
return resultOptions;
}
/// <summary>
/// Sends DHCP reply
/// </summary>
/// <param name="msgType">Type of DHCP message to send</param>
/// <param name="ip">IP for client</param>
/// <param name="replyData">Reply options (will be sent if requested)</param>
public void SendDHCPReply(DHCPMsgType msgType, IPAddress ip, DHCPReplyOptions replyData)
{
SendDHCPReply(msgType, ip, replyData, null);
}
private byte[] CreateOptionStruct(DHCPMsgType msgType, DHCPReplyOptions replyOptions, Dictionary <DHCPOption, byte[]> otherForceOptions)
{
byte[] resultOptions = null;
// Requested options
var reqList = GetRequestedOptionsList();
// Option82?
var relayInfo = this.GetOptionData(DHCPOption.RelayInfo);
CreateOptionElement(ref resultOptions, DHCPOption.DHCPMessageTYPE, new byte[] { (byte)msgType });
// Server identifier - our IP address
if ((replyOptions != null) && (replyOptions.ServerIdentifier != null))
{
CreateOptionElement(ref resultOptions, DHCPOption.ServerIdentifier, replyOptions.ServerIdentifier.GetAddressBytes());
}
// Requested options
if ((reqList != null) && (replyOptions != null))
{
foreach (DHCPOption i in reqList)
{
byte[] optionData = null;
// If it's force option - ignore it. We'll send it later.
if ((otherForceOptions != null) && (otherForceOptions.TryGetValue(i, out optionData)))
{
continue;
}
switch (i)
{
case DHCPOption.SubnetMask:
if (replyOptions.SubnetMask != null)
{
optionData = replyOptions.SubnetMask.GetAddressBytes();
}
break;
case DHCPOption.Router:
if (replyOptions.RouterIP != null)
{
optionData = replyOptions.RouterIP.GetAddressBytes();
}
break;
case DHCPOption.DomainNameServers:
if (replyOptions.DomainNameServers != null)
{
optionData = new byte[] { };
foreach (var dns in replyOptions.DomainNameServers)
{
var dnsserv = dns.GetAddressBytes();
Array.Resize(ref optionData, optionData.Length + 4);
Array.Copy(dnsserv, 0, optionData, optionData.Length - 4, 4);
}
}
break;
case DHCPOption.DomainName:
if (!string.IsNullOrEmpty(replyOptions.DomainName))
{
optionData = System.Text.Encoding.ASCII.GetBytes(replyOptions.DomainName);
}
break;
case DHCPOption.ServerIdentifier:
if (replyOptions.ServerIdentifier != null)
{
optionData = replyOptions.ServerIdentifier.GetAddressBytes();
}
break;
case DHCPOption.LogServer:
if (replyOptions.LogServerIP != null)
{
optionData = replyOptions.LogServerIP.GetAddressBytes();
}
break;
case DHCPOption.StaticRoutes:
case DHCPOption.StaticRoutesWin:
if (replyOptions.StaticRoutes != null)
{
optionData = new byte[] { };
foreach (var route in replyOptions.StaticRoutes)
{
var routeData = route.BuildRouteData();
Array.Resize(ref optionData, optionData.Length + routeData.Length);
Array.Copy(routeData, 0, optionData, optionData.Length - routeData.Length, routeData.Length);
}
}
break;
default:
replyOptions.OtherRequestedOptions.TryGetValue(i, out optionData);
break;
}
if (optionData != null)
{
CreateOptionElement(ref resultOptions, i, optionData);
}
}
}
if (GetMsgType() != DHCPMsgType.DHCPINFORM)
{
// Lease time
if (replyOptions != null)
{
var leaseTime = new byte[4];
leaseTime[3] = (byte)(replyOptions.IPAddressLeaseTime);
leaseTime[2] = (byte)(replyOptions.IPAddressLeaseTime >> 8);
leaseTime[1] = (byte)(replyOptions.IPAddressLeaseTime >> 16);
leaseTime[0] = (byte)(replyOptions.IPAddressLeaseTime >> 24);
CreateOptionElement(ref resultOptions, DHCPOption.IPAddressLeaseTime, leaseTime);
leaseTime[3] = (byte)(replyOptions.RenewalTimeValue_T1);
leaseTime[2] = (byte)(replyOptions.RenewalTimeValue_T1 >> 8);
leaseTime[1] = (byte)(replyOptions.RenewalTimeValue_T1 >> 16);
leaseTime[0] = (byte)(replyOptions.RenewalTimeValue_T1 >> 24);
CreateOptionElement(ref resultOptions, DHCPOption.RenewalTimeValue_T1, leaseTime);
leaseTime[3] = (byte)(replyOptions.RebindingTimeValue_T2);
leaseTime[2] = (byte)(replyOptions.RebindingTimeValue_T2 >> 8);
leaseTime[1] = (byte)(replyOptions.RebindingTimeValue_T2 >> 16);
leaseTime[0] = (byte)(replyOptions.RebindingTimeValue_T2 >> 24);
CreateOptionElement(ref resultOptions, DHCPOption.RebindingTimeValue_T2, leaseTime);
}
}
// Other requested options
if (otherForceOptions != null)
{
foreach (var option in otherForceOptions.Keys)
{
CreateOptionElement(ref resultOptions, option, otherForceOptions[option]);
if (option == DHCPOption.RelayInfo)
{
relayInfo = null;
}
}
}
// Option 82? Send it back!
if (relayInfo != null)
{
CreateOptionElement(ref resultOptions, DHCPOption.RelayInfo, relayInfo);
}
// Create the end option
Array.Resize(ref resultOptions, resultOptions.Length + 1);
Array.Copy(new byte[] { 255 }, 0, resultOptions, resultOptions.Length - 1, 1);
return(resultOptions);
}
