// コンストラクタ（構築）
public DhcpOption53(DhcpPacket.MessageType message_type)
: this()
{
this._Code = 53;
this.message_type_ = message_type;
this._bytes = new byte[1] {
(byte)message_type
};
}
// コンストラクタ
// 受信パケットの Parameter Request List ベース
public DhcpOptions(DhcpPacket.MessageType message_type, PhysicalAddress chaddr, DhcpOption55 dhcpoption55, DhcpLeases dhcplease)
: this()
{
if (message_type == DhcpPacket.MessageType.DHCPOFFER)
{
BuildDHCPOFFER(chaddr, dhcpoption55, dhcplease);
}
if (message_type == DhcpPacket.MessageType.DHCPACK)
{
BuildDHCPACK(chaddr, dhcpoption55, dhcplease);
}
}
// コンストラクタ
// その他のパケットをベースに作成
public DhcpPacket(DhcpPacket basePacket, DhcpPacket.MessageType message_type, DhcpLeases dhcplease)
: this()
{
if (message_type == MessageType.DHCPOFFER)
{
BuildDHCPOFFER(basePacket, dhcplease);
}
if (message_type == MessageType.DHCPACK)
{
BuildDHCPACK(basePacket, dhcplease);
}
}
// 解析
public override void Analyze()
{
this.message_type_ = (DhcpPacket.MessageType)(this._bytes[0]);
if (
(DhcpPacket.MessageType.DHCPDISCOVER <= this.message_type_) &&
(this.message_type_ <= DhcpPacket.MessageType.DHCPINFORM)
)
{
// OK
}
else
{
this.message_type_ = DhcpPacket.MessageType.unknown;
}
}
// UDP送信
private void SendUDP(IPAddress sourceIPAddress, int sourcePort, IPAddress remoteIPAddress, int remotePort)
{
// 送信元
var localEP = new IPEndPoint(sourceIPAddress, sourcePort);
// 送信先
var remoteEP = new IPEndPoint(remoteIPAddress, remotePort);
// 送信データ
DhcpPacket rcv_packet = new DhcpPacket(this.lastRcvBytes_);
DhcpPacket.MessageType snd_message_type =
(rcv_packet.message_type_ == DhcpPacket.MessageType.DHCPDISCOVER)? DhcpPacket.MessageType.DHCPOFFER:
(rcv_packet.message_type_ == DhcpPacket.MessageType.DHCPREQUEST)? DhcpPacket.MessageType.DHCPACK:
DhcpPacket.MessageType.unknown;
if (snd_message_type == DhcpPacket.MessageType.unknown)
{
return;
}
DhcpPacket snd_packet = new DhcpPacket(rcv_packet, snd_message_type, this.dhcplease_);
byte[] msg = snd_packet.GetPacketBytes();
//データを文字列に変換する
string rcvMsg = "0x" + snd_packet.xid_.ToString("X4") + ", " + snd_packet.message_type_;
//送信したデータの情報をRichTextBoxに表示する
string displayMsg = string.Format("{0} [{1} ({2})] > {3}",
DateTime.Now.ToString("HH:mm:ss.fff"), remoteEP.Address, remoteEP.Port, rcvMsg);
textBoxRcvData.BeginInvoke(
new Action <string>(ShowReceivedString), displayMsg);
// 送信イベントデータ
var ev = new SocketAsyncEventArgs();
ev.RemoteEndPoint = remoteEP;
ev.SetBuffer(msg, 0, msg.Length);
// UDP送信
var socket = new Socket(SocketType.Dgram, ProtocolType.Udp);
socket.Bind(localEP); // bindしたIP、ポートと異なる送信元としたい（場合がある）のでudpClient_は使用しない
socket.SendToAsync(ev); // 非同期で送信
socket.Shutdown(SocketShutdown.Both);
socket.Close();
}
