发送tcpsyn代码

⑴ 怎么用C/C++编写发送tcp/ip协议中的syn包

要先装pcap，用Winpcap构造 SYN的数据包

#include<iostream>
usingnamespacestd;
#include<pcap/pcap.h>
#pragmacomment(lib,"wpcap.lib")//要先装pcap，用Winpcap构造SYN的数据包

#include<winsock2.h>
#pragmacomment(lib,"ws2_32.lib")

#include"Packet_Header.h"

#defineMSG_MAXLEN58

USHORTchecksum(USHORT*buf,intsize)
{
	ULONGcksum=0;
	while(size>1)
	{
		cksum+=*buf++;
		size-=sizeof(USHORT);
	}
	if(size)
	{
		cksum+=*(USHORT*)buf;
	}
	cksum=(cksum>>16)+(cksum&0xffff);
	cksum+=(cksum>>16);

	return(USHORT)(~cksum);
}

intmain()
{
	pcap_if_t*alldevs;
	charerrbuf[PCAP_ERRBUF_SIZE]={};
	
	if(-1==pcap_findalldevs(&alldevs,errbuf))
	{
		cout<<"Getdevlisterror"<<endl;
		return-1;
	}

	for(pcap_if_t*d=alldevs;NULL!=d;d=d->next)
	{
		cout<<d->description<<endl;
	}

	pcap_t*pt=pcap_open_live(alldevs->name,65536,true,20,errbuf);
	if(NULL==pt)
	{
		cout<<"Opendeverror"<<endl;
		return-1;
	}

	UCHARSendMsg[MSG_MAXLEN]={0};

	PETHERHDRpethhdr=(PETHERHDR)SendMsg;
	pethhdr->ethDst[0]=0x00;//mac
	pethhdr->ethDst[1]=0x21;
	pethhdr->ethDst[2]=0x85;
	pethhdr->ethDst[3]=0x02;
	pethhdr->ethDst[4]=0x30;
	pethhdr->ethDst[5]=0x4e;
	
	pethhdr->ethSrc[0]=0x00;
	pethhdr->ethSrc[1]=0x23;
	pethhdr->ethSrc[2]=0x8b;
	pethhdr->ethSrc[3]=0xb6;
	pethhdr->ethSrc[4]=0xbd;
	pethhdr->ethSrc[5]=0xd7;

	pethhdr->ethtype=htons(0x0800);

	/*IPheader*/
	PIPHDRpiphdr=(PIPHDR)(SendMsg+sizeof(ETHERHDR));
	piphdr->ipv_l=(4<<4|(sizeof(IPHDR)/sizeof(ULONG)));
	piphdr->iptos=0;
	piphdr->iplen=htons(sizeof(SendMsg)-sizeof(ETHERHDR));
	//piphdr->ipID=htons(0x1234);//0xede6
	piphdr->ipTTL=58;
	piphdr->ipCheckSum=0;
	piphdr->ipProtocol=IPPROTO_TCP;
	piphdr->ipSrc=inet_addr("192.168.0.183");
	piphdr->ipDst=inet_addr("119.75.217.109");//119.75.217.109
	//发送给网络(ip119.75.217.109：80)
	piphdr->ipCheckSum=checksum((USHORT*)piphdr,sizeof(IPHDR));

	/*TCPheader*/
	PTCPHDRptcphdr=(PTCPHDR)(SendMsg+sizeof(ETHERHDR)+sizeof(IPHDR));
	ptcphdr->tcpSrcPort=htons(44523);
	ptcphdr->tcpDstPort=htons(80);
	ptcphdr->tcpSeq=htonl(0x7d2cb526);//0x7d2cb526
	ptcphdr->tcpAck=htonl(0);
	ptcphdr->tcpl_r=((sizeof(TCPHDR)/sizeof(ULONG))<<4|0);
	ptcphdr->tcpFlags=2;
	ptcphdr->tcpWnd=htons(2048);
	ptcphdr->tcpChkSum=0;
	ptcphdr->tcpUrp=0;

	UCHAR*tmpbuf=newUCHAR[sizeof(SendMsg)-sizeof(ETHERHDR)-sizeof(IPHDR)+sizeof(PSDHDR)];
	memset(tmpbuf,0,sizeof(TCPHDR)+sizeof(PSDHDR));
	PPSDHDRppsdhdr=(PPSDHDR)tmpbuf;
	ppsdhdr->psdSrcAddr=piphdr->ipSrc;
	ppsdhdr->psdDstAddr=piphdr->ipDst;
	ppsdhdr->psdzero=0;
	ppsdhdr->psdProto=IPPROTO_TCP;
	ppsdhdr->psdPackLen=htons(sizeof(SendMsg)-sizeof(ETHERHDR)-sizeof(IPHDR));

	memcpy(tmpbuf+sizeof(PSDHDR),SendMsg+sizeof(ETHERHDR)+sizeof(IPHDR),sizeof(tmpbuf+sizeof(PSDHDR)));

	ptcphdr->tcpChkSum=checksum((USHORT*)tmpbuf,sizeof(SendMsg)-sizeof(ETHERHDR)-sizeof(IPHDR));

	if(0!=pcap_sendpacket(pt,SendMsg,sizeof(SendMsg)))
	{
		cout<<"Error"<<endl;
	}

	system("pause");
	return0;
}

⑵ 以太网数据帧的监听与分析

楼上说的对，这不是一句两句话能说玩的，问题也不是一分钟两分钟能解决的了的，编写代码不是一天两天能搞定的。。。楼主，我劝你还是不要对这里报希望了