test_ip.cpp

读取FreeBSD之外的其他Unix下IP层所有接口

#include <iostream>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
#include <net/if.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <sys/socket.h>

using namespace std;

#define MaxIFs 8


int get_ip()
{
    int fd;
    struct ifconf if_conf; /* net/if.h */
    struct sockaddr_in *sin;
	struct in_addr test;
	inet_aton(sin, test);

    fd = socket(PF_INET, SOCK_DGRAM, 0);

    if_conf.ifc_req = (struct ifreq *)malloc(MaxIFs * sizeof(struct ifreq));
    if_conf.ifc_len = MaxIFs * sizeof(struct ifreq);

    if(ioctl(fd, SIOCGIFCONF, &if_conf) == -1)
    {
        perror("ioctl");
        close(fd);
        return 1;
    }
    close(fd);

    printf("all network interfaces\n");
    for (unsigned int i = 0; i < if_conf.ifc_len / sizeof(struct ifreq); i++)
    {
        sin = (struct sockaddr_in *)&if_conf.ifc_req[i].ifr_addr;
        {
            char buf[64];
            const char *p;
            p = inet_ntop(AF_INET, &sin->sin_addr, buf, sizeof(buf));
            if (p == NULL)
            {
                perror("inet_ntop");
                exit(1);
            }
            else
            {
                printf("%8s", if_conf.ifc_req[i].ifr_name);
                printf(": %s\n", p);
            }
        }
    }

    free(if_conf.ifc_req);

    return 0;
}

bool check_ipaddr(const char *szIPAddr)
{
	struct in_addr inp;
	if ( !inet_aton(szIPAddr, &inp) ) 
	{
		cout << "The format of IP address :" << szIPAddr << " is mistaken." <<endl;
		return false;
	}
	unsigned long ulIP = ntohl(inp.s_addr);

	//printf("ulIP = %x\n",ulIP);

	//1.0.0.0         ⅹ   16777216 (01000000)
	//126.255.255.255 ⅹ 2130706431 (7EFFFFFF)
	//128.0.0.0       ⅹ 2147483648 (80000000)
	//191.255.255.255 ⅹ 3221225471 (BFFFFFFF)
	//192.0.0.0       ⅹ 3221225472 (C0000000)
	//223.255.255.255 ⅹ 3758096383 (DFFFFFFF)
	if((ulIP <= 0x01000000) ||
	   (ulIP >= 0x7EFFFFFF && ulIP <= 0x80000000) ||
	   (ulIP >= 0xBFFFFFFF && ulIP <= 0xC0000000) ||
	   (ulIP >= 0xDFFFFFFF))
	{
	    cout << "IP address :" << szIPAddr << " which cannot be set is set." <<endl;
        return false;
	}

    cout << "IP address :" << szIPAddr << " is a validate IP." <<endl;
	return true;
}

int test_ip()
{
    check_ipaddr("10.0.0.1");
    check_ipaddr("127.0.0.1");
    check_ipaddr("1.0.0.0");
    check_ipaddr("126.255.255.255");
    check_ipaddr("191.255.255.255");
    check_ipaddr("223.255.255.255");
    check_ipaddr("255.255.255.255");
    
    get_ip();
    return 0;
}