//?PcapTest.cpp?:?Defines?the?entry?point?for?the?console?application.
#include?“stdio.h“
#include?“pcap.h“
#include?“remote-ext.h“
#include?“winsock.h“
#include?
void?packet_hander（u_char?*paramconst?struct?pcap_pkthdr?*headerconst?u_char?*pkt_data）;
//4字節(jié)的IP地址
typedef?struct?ip_address
{
	u_char?byte1;
	u_char?byte2;
	u_char?byte3;
	u_char?byte4;
}ip_address;
//IP包頭
typedef?struct?ip_header?
{
	u_char?ver_ihl;????//版本?4bit?+?首部長度?4bit
	u_char?tos;?????//服務(wù)類型
	u_short?tlen;????//總長度
	u_short?identification;??
	u_short?flags_fo;
	u_char?ttl;????//存活時間?time?to?live
	u_char?proto;??//協(xié)議
	u_short?crc;
	ip_address?saddr;
	ip_address?daddr;
}ip_header;
//TCP包頭部結(jié)構(gòu)
typedef?struct?tcp_header?{
	WORD?SourPort;
	WORD?DestPort;
	DWORD?SeqNo;
	DWORD?AckNo;
	BYTE?Hlen;
	BYTE?Flag;
	WORD?WndSize;
	WORD?ChkSum;
	WORD?UrgPtr;
}tcp_header;
//TCP偽首部
typedef?struct?tcp_pseheader?
{
	ip_address?saddr;
	ip_address?daddr;
	u_char?placeholder;
	u_char?proto;
	WORD?tcplength;
}tcp_pseheader;
//UDP頭部結(jié)構(gòu)
typedef?struct?udp_header?
{
	u_short?sport;?//源端口
	u_short?dport;?//目的端口
	u_short?len;
	u_short?crc;
}udp_header;
//UDP偽首部
typedef?struct?psd
{
	ip_address?saddr;
	ip_address?daddr;
	char???????????mbz;
	char???????????ptcl;
	unsigned?short?udpl;
}PSD*PPSD;
//DNS結(jié)構(gòu)
typedef?struct?dns
{
	unsigned?short?id;
	unsigned?short?flags;
	unsigned?short?quests;
	unsigned?short?answers;
	unsigned?short?author;
	unsigned?short?addition;
}DNS*PDNS;
//DNS問題結(jié)構(gòu)
typedef?struct?query
{
	unsigned?short?type;
	unsigned?short?classes;
}QUERY*PQUERY;
//DNS回答結(jié)構(gòu)
typedef?struct?response
{
	unsigned?short?name;?
	unsigned?short?type;
	unsigned?short?classes;
	unsigned?short?ttl1;
	unsigned?short?ttl2;
	unsigned?short?length;
	unsigned?short?addr1;
	unsigned?short?addr2;
}RESPONSE*PRESPONSE;
typedef?struct?Author
{
	short?name;
	short?type;
	short?Class;
	int?ttl;
	short?datalength;
};
pcap_t?*adhandle;
int?main（int?argcchar?**argv）
{
	pcap_if_t*?alldevs;
	pcap_if_t*?d;
	int?i=0;
	int?inum;
	char?errbuf[PCAP_ERRBUF_SIZE];
	u_int?netmask;
	char?packet_filter[]=“ip?and?udp“;
	struct?bpf_program?fcode;

	if?（pcap_findalldevs_ex（PCAP_SRC_IF_STRINGNULL&alldevserrbuf）==-1）
	{
		fprintf（stderr“error?in?pcap_findalldevs_ex:%s\r\n“errbuf）;
		printf（“\r\n“）;
		
		return?0;
	}
	for?（d=alldevs;d;d=d->next）
	{
		printf（“%d.%s\n“++id->name）;
		printf（“\r\n“）;
		if?（d->description）
		{
			printf（（“{%s}\n“d->description））;
			printf（“\r\n“）;
		}
		else
		{
			
			printf（“{No?description}\n}“）;
			printf（“\r\n“）;
		}
	}
	if?（i?==?0）
	{
		printf（“{\r\nNo?interface?found!?Make?sure?WinPcap?is?install}“）;
		return?0;
		
	}
	printf（“Enter?the?interface?number{1-%d}:“i）;
	scanf（“%d“&inum）;
	
	if?（inum<1||inum>i）
	{
		printf（“\nInterface?number?out?of?range.\n“）;
		pcap_freealldevs（alldevs）;
		return?-1;
		
	}
	for?（d=alldevsi=0;i