Linux编程之——获取网络IP地址、子网掩码和网卡MAC地址

一、获取网络IP地址

 

char* FIT_GetIpAddr(char* eth)
{
    int fd = 0;
    int iLen = 0;

    int i = 0;
    struct ifreq ifr;
    struct ifreq inter;

    if(NULL == eth)
    {
        return FIT_NULL_IPADDR;
    }

    memset( &inter, 0, sizeof(inter) );
    iLen = strlen(eth);

    fd = socket( PF_INET, SOCK_DGRAM, 0 );
    if( -1 == fd )
    {
        return FIT_NULL_IPADDR;
    }

    memcpy( inter.ifr_name, eth, iLen );
    if (setsockopt( fd, SOL_SOCKET, SO_BINDTODEVICE, (char *)&inter, sizeof(inter)) < 0)
    {
        close(fd);
        return FIT_NULL_IPADDR;
    }

    memset( &ifr,0,sizeof(ifr) );
    memcpy( ifr.ifr_name, eth, iLen );

    if( ioctl(fd, SIOCGIFADDR, &ifr) < 0 )
    {
        close( fd );
        return FIT_NULL_IPADDR;
    }

    if (((ifr.ifr_flags) & IFF_UP) && ((ifr.ifr_flags) & IFF_RUNNING))
    {
        close( fd);
        return inet_ntoa(((struct sockaddr_in*)&(ifr.ifr_addr))->sin_addr);
    }

    close( fd );
    return FIT_NULL_IPADDR;
}

二、获取子网掩码

char* FIT_GetMask(char* eth)
{
    int fd = 0;
    int iLen = 0;

    int i = 0;
    struct ifreq ifr;
    struct ifreq inter;

    if (NULL == eth)
    {
        return FIT_NULL_IPADDR;
    }

    memset( &inter, 0, sizeof(inter) );
    iLen = strlen(eth);

    fd = socket( PF_INET, SOCK_DGRAM, 0 );
    if( -1 == fd )
    {
        return FIT_NULL_IPADDR;
    }

    memcpy( inter.ifr_name, eth, iLen );
    if (setsockopt( fd, SOL_SOCKET, SO_BINDTODEVICE, (char *)&inter, sizeof(inter)) < 0)
    {
        close(fd);
        return FIT_NULL_IPADDR;
    }

    memset( &ifr,0,sizeof(ifr) );
    memcpy( ifr.ifr_name, eth, iLen );

    if( ioctl(fd, SIOCGIFNETMASK, &ifr) < 0 )
    {
        close( fd );
        return FIT_NULL_IPADDR;
    }

    close( fd);

    return inet_ntoa(((struct sockaddr_in*)&(ifr.ifr_addr))->sin_addr);
}

三、获取网卡MAC

char *FIT_GetMac( const char *eth )
{
    int fd = -1;
    int len = 0;

    struct ifreq ifr;
    struct ifreq ifc;

    if(NULL == eth) {
        return FIT_NULL_MACADDR;
    }

    memset(&ifc, 0, sizeof(ifc));
    len = strlen(eth);

    fd = socket( PF_INET, SOCK_DGRAM, 0 );
    if( -1 == fd ) {
        return FIT_NULL_MACADDR;
    }

    memcpy( ifc.ifr_name, eth, len );
    if(setsockopt( fd, SOL_SOCKET, SO_BINDTODEVICE, (char *)&ifc, sizeof(ifc)) < 0 ) {
        close( fd );
        return FIT_NULL_MACADDR;
    }

    memset( &ifr, 0, sizeof(ifr) );
    memcpy( ifr.ifr_name, eth, len );

    if( ioctl( fd, SIOCGIFHWADDR, &ifr) < 0 ) {
        close( fd );
        return FIT_NULL_MACADDR;
    }

    close( fd );

    return ether_ntoa(ifr.ifr_hwaddr.sa_data);
}

说明：
        1、#define     FIT_NULL_IPADDR       "0.0.0.0"
        2、#define     FIT_NULL_MACADDR    "0:0:0:0:0:0"