【C++】C++ 实现ping功能

发表于2021-02-12更新于2022-03-14字数统计689阅读时长6分阅读次数

目的

使用C++实现ping功能，用于在进行TCP/IP通讯前测试是否能与目标主机通讯。

原理

ping 命令是基于ICMP 协议来工作的，「ICMP」全称为Internet 控制报文协议( Internet Control Message Protocol)。基于ICMP协议向目标IP发送ICMP响应请求报文，目标主机收到这个报文之后，会向源IP回复一个ICMP响应应答报文。

C++实现

构建ICMPPing类实现上述功能。

  • icmp_ping.h：
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
#ifndef ICMPPING_H
#define ICMPPING_H

#include <Winsock2.h>
#include <iphlpapi.h> 

#pragma comment(lib,"Iphlpapi.lib")
#pragma comment(lib,"Ws2_32.lib")

class ICMPPing
{
private:
	typedef HANDLE(WINAPI* ICMPCREATEFILE)(VOID);
	typedef BOOL(WINAPI* ICMPCLOSEHANDLE)(HANDLE);
	typedef DWORD(WINAPI* ICMPSENDECHO)(HANDLE, DWORD, LPVOID, WORD, PIP_OPTION_INFORMATION, LPVOID, DWORD, DWORD);
private:
	ICMPPing();
public:
	~ICMPPing();
	static ICMPPing* GetInstance();
	// init ICMP function, return true for success, or for error
	BOOL Init();
	// ping host, return true for connect success, or for timeout
	BOOL Ping(const char* host);
private:
	static ICMPPing* icmp_ping_;
	// pointer of function
	ICMPCREATEFILE pIcmpCreateFile_;
	ICMPCLOSEHANDLE pIcmpCloseHandle_;
	ICMPSENDECHO pIcmpSendEcho_;
};

#endif
  • icmp_ping.cpp：
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
#include "icmp_ping.h"

ICMPPing* ICMPPing::icmp_ping_ = NULL;

ICMPPing::ICMPPing()
    : pIcmpCreateFile_(NULL),
    pIcmpCloseHandle_(NULL),
    pIcmpSendEcho_(NULL)
{
}

ICMPPing::~ICMPPing()
{
    delete icmp_ping_;
}

ICMPPing* ICMPPing::GetInstance()
{
    if (icmp_ping_ == NULL)
        icmp_ping_ = new ICMPPing;

    return icmp_ping_;
}

BOOL ICMPPing::Init()
{
    HINSTANCE hIcmp = LoadLibrary("ICMP.DLL");
    if (hIcmp == NULL)
    {
        return false;
    }
    pIcmpCreateFile_ = (ICMPCREATEFILE)GetProcAddress(hIcmp, "IcmpCreateFile");
    pIcmpCloseHandle_ = (ICMPCLOSEHANDLE)GetProcAddress(hIcmp, "IcmpCloseHandle");
    pIcmpSendEcho_ = (ICMPSENDECHO)GetProcAddress(hIcmp, "IcmpSendEcho");
    if ((pIcmpCreateFile_ == NULL) || (pIcmpCloseHandle_ == NULL) || (pIcmpSendEcho_ == NULL))
        return false;
    return true;
}

BOOL ICMPPing::Ping(const char* host)
{
    DWORD timeOut = 1000;  
    ULONG hAddr = inet_addr(host);  
    if (hAddr == INADDR_NONE)
    {
        hostent* hp = gethostbyname(host);   
        if (hp)
            memcpy(&hAddr, hp->h_addr_list, hp->h_length); 
        else
        {
            return false;
        }
    }
    HANDLE hIp = pIcmpCreateFile_();
    IP_OPTION_INFORMATION ipoi;
    memset(&ipoi, 0, sizeof(IP_OPTION_INFORMATION));
    ipoi.Ttl = 128;  

    unsigned char pSend[36];  
    memset(pSend, 'E', 32);

    int repSize = sizeof(ICMP_ECHO_REPLY) + 32;
    unsigned char pReply[100]; 
    ICMP_ECHO_REPLY* pEchoReply = (ICMP_ECHO_REPLY*)pReply;

    DWORD nPackets = pIcmpSendEcho_(hIp, hAddr, pSend, 32, &ipoi, pReply, repSize, timeOut);   

    if (pEchoReply->Status != 0)
    {
        pIcmpCloseHandle_(hIp);
        return false;
    }

    pIcmpCloseHandle_(hIp);
    return true;
}

该类使用单例模式，在主程序中使用时，通过调用GetInstance()函数返回类指针对象；之后通过Init()函数进行初始化，并判断返回值是否为false；最后调用Ping()函数验证是否能和目标主机进行通讯。

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
#include "icmp_ping.h"
#include <iostream>

int main()
{
    ICMPPing* icmp_ping = ICMPPing::GetInstance();

    if (!icmp_ping->Init())
        std::cout << "init error!" << std::endl;

    if (icmp_ping->Ping("192.168.0.12")){
        std::cout << "ping success!" << std::endl;
    } else{
        std::cout << "ping fail!" << std::endl;
    }

    return 0;
}

注意

若该类同时与其他包含有<Windows.h>的文件放在同一项目下编译时，会报重定义的错误，这是因为<Windows.h>中包含了<Winsock.h>头文件，而本类包含了<Winsock2.h>文件，因此会有重定义。解决方案：

在项目属性 ——> C/C++ ———> 预处理器 -------> 预处理器定义

增加如下定义

WIN32_LEAN_AND_MEAN

致谢

代码参考自http://www.cnblogs.com/guoyz1314/p/3527340.html