原始套接字

原始套接字
套接字类型指定为SOCK_RAW
socket(AF_INET, SOCK_STREAM, 0);
创建原始套接字时 第三个参数将成为IP头中协议域的值

发送ICMP报文时 必须由程序自己计算校验和
FUNC：将数据以字为单位 加到一个双字中

如果数据长度是奇数 最后一个字节将被扩展到字 

最后将这个双子的高16位和低16位相加后取反

// 原始套接字.cpp : 定义控制台应用程序的入口点。
//

#include "stdafx.h"

#include <WinSock2.h>
#include <Windows.h>
#pragma comment(lib,"ws2_32.lib")

class CInitSock		
{
public:
	CInitSock(BYTE minorVer = 2, BYTE majorVer = 2)
	{
		// 初始化WS2_32.dll
		WSADATA wsaData;
		WORD sockVersion = MAKEWORD(minorVer, majorVer);
		if(::WSAStartup(sockVersion, &wsaData) != 0)
		{
			exit(0);
		}
	}
	~CInitSock()
	{	
		::WSACleanup();	
	}
};

CInitSock theSock;
typedef struct icmp_hdr
{
	unsigned char   icmp_type;		// 消息类型
	unsigned char   icmp_code;		// 代码
	unsigned short  icmp_checksum;	// 校验和
	// 下面是回显头
	unsigned short  icmp_id;		// 用来惟一标识此请求的ID号，通常设置为进程ID
	unsigned short  icmp_sequence;	// 序列号
	unsigned long   icmp_timestamp; // 时间戳
} ICMP_HDR, *PICMP_HDR;

typedef struct _IPHeader		// 20字节的IP头
{
	UCHAR     iphVerLen;      // 版本号和头长度（各占4位）
	UCHAR     ipTOS;          // 服务类型 
	USHORT    ipLength;       // 封包总长度，即整个IP报的长度
	USHORT    ipID;			  // 封包标识，惟一标识发送的每一个数据报
	USHORT    ipFlags;	      // 标志
	UCHAR     ipTTL;	      // 生存时间，就是TTL
	UCHAR     ipProtocol;     // 协议，可能是TCP、UDP、ICMP等
	USHORT    ipChecksum;     // 校验和
	ULONG     ipSource;       // 源IP地址
	ULONG     ipDestination;  // 目标IP地址
} IPHeader, *PIPHeader; 
#pragma region 检查校验和
USHORT CheckSum(USHORT* szBuffer,int size)
{

	unsigned long uCkSum = 0;
	//将数据以字为单位累加到uCkSum中
	while (size >1)
	{
		uCkSum += *szBuffer++;
		size -= sizeof(USHORT);
	}
	if (size)		//奇数
	{
		uCkSum += *(UCHAR*)szBuffer;
	}
	uCkSum = (uCkSum >> 16) + (uCkSum & 0xffff);
	uCkSum += (uCkSum >> 16);
	return (USHORT)(~uCkSum);
}
#pragma endregion 检查校验和

BOOL SetTimeout(SOCKET s, int nTime, BOOL bRecv)
{
	int ret = ::setsockopt(s, SOL_SOCKET, 
		bRecv ? SO_RCVTIMEO : SO_SNDTIMEO, (char*)&nTime, sizeof(nTime));
	return ret != SOCKET_ERROR;
}
int _tmain(int argc, _TCHAR* argv[])
{
	// 目的IP地址，即要Ping的IP地址
	char szDestIp[] = "127.0.0.1";	// 127.0.0.1

	// 创建原始套节字
	SOCKET sRaw = ::socket(AF_INET, SOCK_RAW, IPPROTO_ICMP);

	// 设置接收超时
	SetTimeout(sRaw, 1000, TRUE);

	// 设置目的地址
	SOCKADDR_IN dest;
	dest.sin_family = AF_INET;
	dest.sin_port = htons(0);
	dest.sin_addr.S_un.S_addr = inet_addr(szDestIp);

	// 创建ICMP封包
	char szBuffer[sizeof(ICMP_HDR) + 32];
	ICMP_HDR* pIcmp = (ICMP_HDR*)szBuffer;
	// 填写ICMP封包数据
	pIcmp->icmp_type = 8;	// 请求一个ICMP回显
	pIcmp->icmp_code = 0;
	pIcmp->icmp_id = (USHORT)::GetCurrentProcessId();
	pIcmp->icmp_checksum = 0;
	pIcmp->icmp_sequence = 0;
	// 填充数据部分，可以为任意
	memset(&szBuffer[sizeof(ICMP_HDR)], 'E', 32);

	// 开始发送和接收ICMP封包
	USHORT	nSeq = 0;
	char recvBuf[1024];
	SOCKADDR_IN from;
	int nLen = sizeof(from);
	while(TRUE)
	{
		static int nCount = 0;
		int nRet;
		if(nCount++ == 4)
			break;
		pIcmp->icmp_checksum = 0;
		pIcmp->icmp_timestamp = ::GetTickCount();
		pIcmp->icmp_sequence = nSeq++;
		pIcmp->icmp_checksum = CheckSum((USHORT*)szBuffer, sizeof(ICMP_HDR) + 32);
		nRet = ::sendto(sRaw, szBuffer, sizeof(ICMP_HDR) + 32, 0, (SOCKADDR *)&dest, sizeof(dest));
		if(nRet == SOCKET_ERROR)
		{
			printf(" sendto() failed: %d 
", ::WSAGetLastError());	//以管理员权限开启
			return -1;
		}
		nRet = ::recvfrom(sRaw, recvBuf, 1024, 0, (sockaddr*)&from, &nLen);
		if(nRet == SOCKET_ERROR)
		{
			if(::WSAGetLastError() == WSAETIMEDOUT)
			{
				printf(" timed out
");
				continue;
			}
			printf(" recvfrom() failed: %d
", ::WSAGetLastError());
			return -1;
		}

		// 下面开始解析接收到的ICMP封包
		int nTick = ::GetTickCount();
		if(nRet < sizeof(IPHeader) + sizeof(ICMP_HDR))
		{
			printf(" Too few bytes from %s 
", ::inet_ntoa(from.sin_addr));
		}
		// 接收到的数据中包含IP头，IP头大小为20个字节，所以加20得到ICMP头
		ICMP_HDR* pRecvIcmp = (ICMP_HDR*)(recvBuf + 20); // (ICMP_HDR*)(recvBuf + sizeof(IPHeader));
		if(pRecvIcmp->icmp_type != 0)	// 回显
		{
			printf(" nonecho type %d recvd 
", pRecvIcmp->icmp_type);
			return -1;
		}

		if(pRecvIcmp->icmp_id != ::GetCurrentProcessId())
		{
			printf(" someone else's packet! 
");
			return -1;
		}

		printf(" %d bytes from %s:", nRet, inet_ntoa(from.sin_addr));
		printf(" icmp_seq = %d. ", pRecvIcmp->icmp_sequence);
		printf(" time: %d ms", nTick - pRecvIcmp->icmp_timestamp);
		printf(" 
");

		::Sleep(1000);
	}

	return 0;
}

　　

// 路由跟踪.cpp : 定义控制台应用程序的入口点。
//

#include "stdafx.h"

#include <WinSock2.h>
#include <Windows.h>
#include "Ws2tcpip.h"
#pragma comment (lib,"ws2_32.lib")

class CInitSock		
{
public:
	CInitSock(BYTE minorVer = 2, BYTE majorVer = 2)
	{
		// 初始化WS2_32.dll
		WSADATA wsaData;
		WORD sockVersion = MAKEWORD(minorVer, majorVer);
		if(::WSAStartup(sockVersion, &wsaData) != 0)
		{
			exit(0);
		}
	}
	~CInitSock()
	{	
		::WSACleanup();	
	}
};

CInitSock theSock;

typedef struct icmp_hdr
{
	unsigned char   icmp_type;		// 消息类型
	unsigned char   icmp_code;		// 代码
	unsigned short  icmp_checksum;	// 校验和
	// 下面是回显头
	unsigned short  icmp_id;		// 用来惟一标识此请求的ID号，通常设置为进程ID
	unsigned short  icmp_sequence;	// 序列号
	unsigned long   icmp_timestamp; // 时间戳
} ICMP_HDR, *PICMP_HDR;

#pragma region 检查校验和
USHORT CheckSum(USHORT* szBuffer,int size)
{

	unsigned long uCkSum = 0;
	//将数据以字为单位累加到uCkSum中
	while (size >1)
	{
		uCkSum += *szBuffer++;
		size -= sizeof(USHORT);
	}
	if (size)		//奇数
	{
		uCkSum += *(UCHAR*)szBuffer;
	}
	uCkSum = (uCkSum >> 16) + (uCkSum & 0xffff);
	uCkSum += (uCkSum >> 16);
	return (USHORT)(~uCkSum);
}
#pragma endregion 检查校验和
BOOL SetTTL(SOCKET s, int nValue)
{
	int ret = ::setsockopt(s, IPPROTO_IP, IP_TTL, (char*)&nValue, sizeof(nValue));
	return ret != SOCKET_ERROR;
}
BOOL SetTimeout(SOCKET s, int nTime, BOOL bRecv)
{
	int ret = ::setsockopt(s, SOL_SOCKET, 
		bRecv ? SO_RCVTIMEO : SO_SNDTIMEO, (char*)&nTime, sizeof(nTime));
	return ret != SOCKET_ERROR;
}
int _tmain(int argc, _TCHAR* argv[])
{
	char *szDestIp = "192.168.0.103"; // 210.181.18.12910.16.115.25 61.55.66.30

	char recvBuf[1024] = { 0 };

	// 创建用于接收ICMP封包的原始套节字，绑定到本地端口
	SOCKET sRaw = ::socket(AF_INET, SOCK_RAW, IPPROTO_ICMP);
	sockaddr_in in;
	in.sin_family = AF_INET;
	in.sin_port = 0;
	in.sin_addr.S_un.S_addr = INADDR_ANY;
	if(::bind(sRaw, (sockaddr*)&in, sizeof(in)) == SOCKET_ERROR)
	{
		printf(" bind() failed 错误码: %d
",WSAGetLastError());
		return 0;
	}

	SetTimeout(sRaw, 5*1000,TRUE);

	// 创建用于发送UDP封包的套节字
	SOCKET sSend = ::socket(AF_INET, SOCK_DGRAM, 0);	

	SOCKADDR_IN destAddr;
	destAddr.sin_family = AF_INET;
	destAddr.sin_port = ::htons(22);
	destAddr.sin_addr.S_un.S_addr = ::inet_addr(szDestIp);


	int nTTL = 1;
	int nRet;
	ICMP_HDR *pICMPHdr;
	int nTick;	
	SOCKADDR_IN recvAddr;
	do
	{
		// 设置UDP封包的TTL值
		SetTTL(sSend, nTTL);
		nTick = ::GetTickCount();

		// 发送这个UDP封包
		nRet = ::sendto(sSend, "hello", 5, 0, (sockaddr*)&destAddr, sizeof(destAddr));
		if(nRet == SOCKET_ERROR)
		{
			printf(" sendto() failed 
");
			break;
		}


		// 等待接收路由器返回的ICMP报文
		int nLen = sizeof(recvAddr);
		nRet = ::recvfrom(sRaw, recvBuf, 1024, 0, (sockaddr*)&recvAddr, &nLen);
		if(nRet == SOCKET_ERROR)
		{
			if(::WSAGetLastError() == WSAETIMEDOUT)
			{
				printf(" time out 
");
				break;
			}
			else
			{
				printf(" recvfrom() failed 
");
				break;
			}
		}

		// 解析接收到的ICMP数据
		pICMPHdr = (ICMP_HDR*)&recvBuf[20]; // sizeof(IPHeader)

		if(pICMPHdr->icmp_type != 11 && pICMPHdr->icmp_type != 3 && pICMPHdr->icmp_code != 3)
		{
			printf(" Unexpected Type: %d , code: %d 
",
				pICMPHdr->icmp_type, pICMPHdr->icmp_code);
		}
		else
		{
			char *szIP = ::inet_ntoa(recvAddr.sin_addr);

			printf(" 第%d个路由器，IP地址：%s 
", nTTL, szIP);
			printf("      用时：%d毫秒 
", ::GetTickCount() - nTick);
		}

		if(destAddr.sin_addr.S_un.S_addr == recvAddr.sin_addr.S_un.S_addr)
		{	
			printf("目标可达 
");
			break;
		}

		printf("//------------------------------------// 
");

	}while(nTTL++ < 20);

	::closesocket(sRaw);
	::closesocket(sSend);
	return 0;
}