linux 设置网络API --- 开/关网卡、设置/获取Mac地址

标签：des   blog   os   使用   io   ar   2014   问题   cti   

最近在做项目过程中，由于在多线程中使用system函数，有时候出现莫名程序异常终止，最后决定替换所有的system函数，但是对于设置mac地址这个函数试了很多次都没有成功；今天在此总结下原因：

1. 编写的关闭/打开网卡函数没有延时；（一般情况设置开关网卡可能需要初始化，所以如果开关连续可能没有初始化成功，你可以试试在嵌入式Linux命令行下快速的开关网卡，也是没有反应的）

2. 类型转换问题；（由于为了便捷，使用sscanf提取mac字符串，如果使用8bit提取%x,转换出错，最后只能使用32bit，再一个个赋值即可）

#include <stdio.h>
#include <stdlib.h>
#include <sys/ioctl.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <net/if.h>
#include <netinet/in.h>

typedef signed   char   INT8S;
typedef unsigned char 	INT8U;
typedef signed   short  INT16S;
typedef unsigned short  INT16U;
typedef signed 	 int    INT32S;
typedef unsigned int    INT32U;



//add by lightd, 2014-06-04
//============================================================================
//Function:    ifconfig_ethx_down_API 
//Description: 关闭本地指定网卡 - eg: ifconfig eth0 down
//Input: 			 
//Output: 		 
//Return: 		 			
//Others:	   None
//============================================================================
INT8S ifconfig_ethx_down_API(const INT8U *interface_name)
{
	INT32S 		 sock_fd;
	struct ifreq ifr;
	int			 selector; 
	 
	//传入参数合法性检测
	if(interface_name == NULL)
	{
		fprintf(stdout, "%s:%d: args invalid!", __FUNCTION__, __LINE__);
		return -1;
	}
	
	//禁止关闭回环
	if(strncmp((char *)interface_name, (char *)"lo", 2) == 0)
    {
       fprintf(stdout, "%s:%d: You can't pull down interface lo!",  __FUNCTION__, __LINE__);
       return 0;    
    }
   
    sock_fd = socket(AF_INET, SOCK_DGRAM, 0);
    if(sock_fd < 0)
    {
        fprintf(stdout, "%s:%d: socket failed!",  __FUNCTION__, __LINE__);
        return -2;
    }

    sprintf(ifr.ifr_name, "%s", interface_name);
   
    if(ioctl(sock_fd, SIOCGIFFLAGS, &ifr) < 0)
    {
        fprintf(stdout, "%s:%d: ioctl failed 1!",  __FUNCTION__, __LINE__);
        return -3;
    }
	
	selector = IFF_UP;
    ifr.ifr_flags &= ~selector; 
    if(ioctl(sock_fd, SIOCSIFFLAGS, &ifr) < 0)
    {
        fprintf(stdout, "%s:%d: ioctl failed 2!",  __FUNCTION__, __LINE__);
        return -4;
    }

	close( sock_fd );
	
    return 0;
}

//add by lightd, 2014-06-04
//============================================================================
//Function:    ifconfig_ethx_up_API 
//Description: 打开本地指定网卡 - eg: ifconfig eth0 up
//Input: 			 
//Output: 		 
//Return: 		 			
//Others:			 None
//============================================================================
INT8S ifconfig_ethx_up_API(const INT8U *interface_name)
{
	INT32S		 	sock_fd;
	struct ifreq 	ifr;
	int			 	selector; 
	
	//传入参数合法性检测
	if(interface_name == NULL)
	{
		fprintf(stdout, "%s:%d: args invalid!",  __FUNCTION__, __LINE__);
		return -1;
	}

	sock_fd = socket(AF_INET, SOCK_DGRAM, 0);
	if(sock_fd < 0)
	{
		fprintf(stdout, "%s:%d: create socket failed!",  __FUNCTION__, __LINE__);
		return -2;
	}
	
	sprintf(ifr.ifr_name, "%s", interface_name);
	if(ioctl(sock_fd, SIOCGIFFLAGS, &ifr) < 0)
	{
		fprintf(stdout, "%s:%d: ioctl error 1",  __FUNCTION__, __LINE__);
		return -3;
	}
	
	selector = (IFF_UP | IFF_RUNNING);
	ifr.ifr_flags |= selector;  
	if(ioctl(sock_fd, SIOCSIFFLAGS, &ifr) < 0)
	{
		fprintf(stdout, "%s:%d: ioctl error 2",  __FUNCTION__, __LINE__);
		return -4;
	}

	close( sock_fd );
	
	return 0;	
}



//add by lightd, 2014-06-04
//============================================================================
//Function:    SetLocalMACAddr_API 
//Description: 设置本地指定网卡的MAC
//Input: 			 
//Output: 		 
//Return: 		 			
//Others:	   None
//Test result: 测试结果 - 连续调用20次不出错
//============================================================================
INT8S SetLocalMACAddr_API(const INT8U *interface_name, const INT8U *str_macaddr)  
{
	int 			ret;  
	int 			sock_fd;  
    struct ifreq 	ifr;      
	INT32U 			mac2bit[6];
	
	//传入参数合法性检测
	if(interface_name == NULL || str_macaddr == NULL)
	{
		fprintf(stdout, "%s:%d: args invalid!",  __FUNCTION__, __LINE__);
		return -1;
	}
	
	//提取mac格式 
	sscanf((char *)str_macaddr, "%02X:%02X:%02X:%02X:%02X:%02X", (INT8U *)&mac2bit[0], (INT8U *)&mac2bit[1], (INT8U *)&mac2bit[2], (INT8U *)&mac2bit[3], (INT8U *)&mac2bit[4], (INT8U *)&mac2bit[5]);
	
    sock_fd = socket(PF_INET, SOCK_DGRAM, 0);  
    if (sock_fd < 0)  
    {  
		perror("socket error");  	  
        return -2;  
    }  
	
	//设置mac前，必须关闭对应的网卡 - 否则出错
    ret = ifconfig_ethx_down_API( interface_name );
	if(ret < 0)
	{
		fprintf(stdout, "%s:%d: close eth0 error",  __FUNCTION__, __LINE__);
		return -3;
	}
	sleep(1); //等待网卡关闭OK
	
    sprintf(ifr.ifr_ifrn.ifrn_name, "%s", interface_name);  
    ifr.ifr_ifru.ifru_hwaddr.sa_family = 1;  
	ifr.ifr_ifru.ifru_hwaddr.sa_data[0] = mac2bit[0];
	ifr.ifr_ifru.ifru_hwaddr.sa_data[1] = mac2bit[1];
	ifr.ifr_ifru.ifru_hwaddr.sa_data[2] = mac2bit[2];
	ifr.ifr_ifru.ifru_hwaddr.sa_data[3] = mac2bit[3];
	ifr.ifr_ifru.ifru_hwaddr.sa_data[4] = mac2bit[4];
	ifr.ifr_ifru.ifru_hwaddr.sa_data[5] = mac2bit[5];
	
    ret = ioctl(sock_fd, SIOCSIFHWADDR, &ifr);  
    if (ret != 0)  
    {  
		perror("set mac address erorr");
        return -4;  
    }  
	
	close( sock_fd );
	
    ret = ifconfig_ethx_up_API( interface_name );
	if(ret < 0)
	{
		fprintf(stdout, "%s:%d: open eth0 error!",  __FUNCTION__, __LINE__);
		return -5;
	}
	
	sleep(2); //等待网卡打开OK

	
    return 0;  
}

//add by lightd, 2014-06-04
//============================================================================
//Function:    GetLocalMACAddr_API 
//Description: 获取本地指定网卡的MAC
//Input: 			 
//Output: 		 
//Return: 		 			
//Others:	   None
//============================================================================
INT8S GetLocalMACAddr_API(const INT8U *interface_name, INT8U *str_macaddr)  
{  
    INT32S 		 sock_fd;  
    struct ifreq ifr_mac;  
	
	//传入参数合法性检测
	if(interface_name == NULL || str_macaddr == NULL)
	{
		fprintf(stdout, "%s:%d: args invalid!",  __FUNCTION__, __LINE__);
		return -1;
	}
	
    sock_fd = socket( AF_INET, SOCK_STREAM, 0 );  
    if( sock_fd == -1)  
    {  
        perror("create socket failed");  
		sprintf((char *)str_macaddr, "00:00:00:00:00:00");
        return -2;  
    }  
      
	//指定网卡
    memset(&ifr_mac, 0, sizeof(ifr_mac));     
    sprintf(ifr_mac.ifr_name, "%s", interface_name);     
  
	//获取指定网卡的mac地址
    if( (ioctl( sock_fd, SIOCGIFHWADDR, &ifr_mac)) < 0 ) 
    {  
        perror("mac ioctl error");  
		sprintf((char *)str_macaddr, "00:00:00:00:00:00");
        return -3;  
    }  
      
	close( sock_fd );  
	
    sprintf((char *)str_macaddr,"%02x:%02x:%02x:%02x:%02x:%02x",  
            (unsigned char)ifr_mac.ifr_hwaddr.sa_data[0],  
            (unsigned char)ifr_mac.ifr_hwaddr.sa_data[1],  
            (unsigned char)ifr_mac.ifr_hwaddr.sa_data[2],  
            (unsigned char)ifr_mac.ifr_hwaddr.sa_data[3],  
            (unsigned char)ifr_mac.ifr_hwaddr.sa_data[4],  
            (unsigned char)ifr_mac.ifr_hwaddr.sa_data[5]);  
  
    printf("local mac:<%s> \n", str_macaddr);      
    
    return 0;
}



int main(void)
{
	INT8U str_macaddr[20];
	
	memset(str_macaddr, 0, sizeof(str_macaddr));
	GetLocalMACAddr_API("eth0", str_macaddr);
	fprintf(stdout, "1 mac: %s\n", str_macaddr);
	
	//ifconfig_ethx_down_API("eth0");
		
	//system("ifconfig eth0 down");
	//usleep(500000);
	//system("ifconfig eth0 up");
	//usleep(500000);
	//sleep(1); //10ms
	//ifconfig_ethx_down_API("eth0");
	//sleep(1);
	
	SetLocalMACAddr_API("eth0", "08:00:11:22:33:44");
	//ifconfig_ethx_up_API("eth0");
	//ifconfig_ethx_up_API("eth0");
	//sleep(2); 
	
	memset(str_macaddr, 0, sizeof(str_macaddr));
	GetLocalMACAddr_API("eth0", str_macaddr);
	fprintf(stdout, "2 mac: %s\n", str_macaddr);
	
	system("ping 200.200.200.100");
	//usleep(50000); 
	//ifconfig_ethx_down_API("eth0");
	//ifconfig_ethx_up_API("eth0");

	//memset(str_macaddr, 0, sizeof(str_macaddr));
	//GetLocalMACAddr_API("eth0", str_macaddr);
	fprintf(stdout, "2 mac: %s\n", str_macaddr);
		
	return 0;
}

linux 设置网络API --- 开/关网卡、设置/获取Mac地址

标签：des   blog   os   使用   io   ar   2014   问题   cti   

原文地址：http://blog.csdn.net/dl0914791011/article/details/38959471