Linux中ifreq 结构体分析和使用 及其在项目中的简单应用

[基础知识说明]

结构原型:

/*
* Interface request structure used for socket
* ioctl's. All interface ioctl's must have parameter
* definitions which begin with ifr_name. The
* remainder may be interface specific.
*/

struct ifreq
{
#define IFHWADDRLEN 6
union
{
char ifrn_name[IFNAMSIZ]; /* if name, e.g. "en0" */
} ifr_ifrn;

union {
struct sockaddr ifru_addr;
struct sockaddr ifru_dstaddr;
struct sockaddr ifru_broadaddr;
struct sockaddr ifru_netmask;
struct sockaddr ifru_hwaddr;
short ifru_flags;
int ifru_ivalue;
int ifru_mtu;
struct ifmap ifru_map;
char ifru_slave[IFNAMSIZ]; /* Just fits the size */
char ifru_newname[IFNAMSIZ];
void __user * ifru_data;
struct if_settings ifru_settings;
} ifr_ifru;
};

#define ifr_name ifr_ifrn.ifrn_name /* interface name */
#define ifr_hwaddr ifr_ifru.ifru_hwaddr /* MAC address */
#define ifr_addr ifr_ifru.ifru_addr /* address */
#define ifr_dstaddr ifr_ifru.ifru_dstaddr /* other end of p-p lnk */
#define ifr_broadaddr ifr_ifru.ifru_broadaddr /* broadcast address */
#define ifr_netmask ifr_ifru.ifru_netmask /* interface net mask */
#define ifr_flags ifr_ifru.ifru_flags /* flags */
#define ifr_metric ifr_ifru.ifru_ivalue /* metric */
#define ifr_mtu ifr_ifru.ifru_mtu /* mtu */
#define ifr_map ifr_ifru.ifru_map /* device map */
#define ifr_slave ifr_ifru.ifru_slave /* slave device */
#define ifr_data ifr_ifru.ifru_data /* for use by interface */
#define ifr_ifindex ifr_ifru.ifru_ivalue /* interface index */
#define ifr_bandwidth ifr_ifru.ifru_ivalue /* link bandwidth */
#define ifr_qlen ifr_ifru.ifru_ivalue /* Queue length */
#define ifr_newname ifr_ifru.ifru_newname /* New name */
#define ifr_settings ifr_ifru.ifru_settings /* Device/proto settings*/

基本介绍:

ifreq结构定义在/usr/include/net/if.h，用来配置ip地址，激活接口，配置MTU等接口信息的。其中包含了一个接口的名字和具体内容——（是个共用体，有可能是IP地址，广播地址，子网掩码，MAC号，MTU或其他内容）。ifreq包含在ifconf结构中。而ifconf结构通常是用来保存所有接口的信息的。

举例说明：

在Linux系统中，ifconfig命令是通过ioctl接口与内核通信，例如，当系统管理员输入如下命令来改变接口eth0的MTU大小：

ifconfig eth0 mtu 1250

ifconfig命令首先打开一个socket，然后通过系统管理员输入的参数初始化一个数据结构，并通过ioctl调用将数据传送到内核。SIOCSIFMTU是命令标识符。

struct ifreq data;
fd = socket(PF_INET, SOCK_DGRAM, 0);
< ... initialize "data" ...>
err = ioctl(fd, SIOCSIFMTU, &data);

[举例应用]

/**
*
* \brief   通过广播socket获取系统eth0当前IP地址
*
* \param   pAddr   存储IP地址的内存地址，不小于16个字节。
*
* \Return  0       成功
*          else    失败
*/
int  GetSysIpBySocket(char* pAddr)
{
if ( pAddr == NULL )
{
return RET_ERR_PARAM;
}

struct sockaddr_in *sin;
struct ifreq        ifr;

int sock = socket(AF_INET,SOCK_DGRAM,0);
if(sock <= 0)
{
perror("socket error!\n");
return RET_ERROR;
}

strcpy(ifr.ifr_name,"eth0");

if(ioctl(sock,SIOCGIFADDR,&ifr) < 0)
{
perror("ioctl error\n");
close(sock);
return RET_ERROR;
}
else
{
sin = (struct sockaddr_in *)&(ifr.ifr_addr);
strcpy(pAddr, inet_ntoa(sin->sin_addr));
close(sock);
}
return RET_OK;
}

/**
*
* \brief   通过广播socket获取系统eth0当前子网掩码
*
* \param   pMask   存储子网掩码的内存地址，不小于16个字节。
*
* \Return  0       成功
*          else    失败
*/
int  GetSysMaskBySocket(char* pMask)
{
if ( pMask == NULL )
{
return RET_ERR_PARAM;
}

struct sockaddr_in *sin;
struct ifreq        ifr;

int sock = socket(AF_INET,SOCK_DGRAM,0);
if(sock <= 0)
{
perror("socket error!\n");
return RET_ERROR;
}

strcpy(ifr.ifr_name,"eth0");

if(ioctl(sock,SIOCGIFNETMASK,&ifr) < 0)
{
perror("ioctl error\n");
close(sock);
return RET_ERROR;
}
else
{
sin = (struct sockaddr_in *)&(ifr.ifr_netmask);
strcpy(pMask, inet_ntoa(sin->sin_addr));
close(sock);
}

return RET_OK;
}

/**
*
* \brief   通过广播socket获取系统eth0当前IP地址和子网掩码
*
* \param   pAddr   存储IP地址的内存地址，不小于16个字节。
* \param   pMask   存储子网掩码的内存地址，不小于16个字节。
*
* \Return  0       成功
*          else    失败
*/
int GetSysIpMaskBySocket(char* pAddr, char* pMask)
{
if ( pAddr == NULL || pMask == NULL )
{
return RET_ERR_PARAM;
}

struct sockaddr_in *sin;
struct ifreq        ifr;

int sock = socket(AF_INET,SOCK_DGRAM,0);
if(sock <= 0)
{
perror("socket error!\n");
return RET_ERROR;
}

strcpy(ifr.ifr_name,"eth0");

if(ioctl(sock,SIOCGIFADDR,&ifr) < 0)
{
perror("ioctl SIOCGIFADDR error\n");
close(sock);
return RET_ERROR;
}
else
{
sin = (struct sockaddr_in *)&(ifr.ifr_addr);
strcpy(pAddr, inet_ntoa(sin->sin_addr));
}

if(ioctl(sock,SIOCGIFNETMASK,&ifr) < 0)
{
perror("ioctl SIOCGIFNETMASK error\n");
close(sock);
return RET_ERROR;
}
else
{
sin = (struct sockaddr_in *)&(ifr.ifr_netmask);
strcpy(pMask, inet_ntoa(sin->sin_addr));

}

close(sock);
return RET_OK;
}

/**
*
* \brief   通过ioctl获取系统eth0 Mac地址
*
* \param   pMask   存储 Mac地址的内存地址，不小于18个字节。
*
* \Return  0       成功
*          else    失败
*/
int  GetSysMacBySocket(char* pMac)
{
if ( pMac == NULL )
{
return RET_ERR_PARAM;
}

struct ifreq        ifr;

int sock = socket(AF_INET,SOCK_DGRAM,0);
if(sock <= 0)
{
perror("socket error!\n");
return RET_ERROR;
}

strcpy(ifr.ifr_name,"eth0");

if(ioctl(sock,SIOCGIFHWADDR,&ifr) < 0)
{
perror("ioctl SIOCGIFHWADDR error\n");
close(sock);
return RET_ERROR;
}
else
{
sprintf(pMac, "%02x:%02x:%02x:%02x:%02x:%02x",
(unsigned char)ifr.ifr_hwaddr.sa_data[0],
(unsigned char)ifr.ifr_hwaddr.sa_data[1],
(unsigned char)ifr.ifr_hwaddr.sa_data[2],
(unsigned char)ifr.ifr_hwaddr.sa_data[3],
(unsigned char)ifr.ifr_hwaddr.sa_data[4],
(unsigned char)ifr.ifr_hwaddr.sa_data[5]);
}

close(sock);
return RET_OK;
}

参考H CPP文件

/*
* =====================================================================================
*
*       Filename:  ipconfig.h
*
*    Description:  基于ifconfig命令，获取、配置系统当前网络配置参数。
*
*        Version:  1.0
*        Created:  11/23/2012 01:42:16 PM HKT
*       Revision:  none
*       Compiler:  gcc
*
*         Author:
*        Company:
*
* =====================================================================================
*/

#ifndef  IPCONFIG_INC
#define  IPCONFIG_INC

bool IsIpValid   (const char* pAddr);
bool IsMaskValid (const char* pNetMask);
bool IsMacValid  (const char* pMac);
bool IsGatewayValid(const char* pGateway);

int  GetSysIp    (char* pAddr);
int  GetSysMask  (char* pMask);
int  GetSysIpMask(char* pAddr, char* pMask);
int  GetSysMac   (char* pMac);
int  GetSysGateway(char* pGateway);
int  GetSysBroadcast(const char* pAddr, const char* pMask, char* pBc);

int  GetSysIpBySocket    (char* pAddr);
int  GetSysMaskBySocket  (char* pMask);
int  GetSysIpMaskBySocket(char* pAddr, char* pMask);
int  GetSysMacBySocket   (char* pMac);

int  SetSysIp    (const char* pAddr);
int  SetSysMask  (const char* pNetMask);
int  SetSysMac   (const char* pMac);
int  SetSysIpMask(const char* pAddr, const char* pNetMask);
int  SetSysGateway(const char* pGateway);

#endif   /* ----- #ifndef IPCONFIG_INC  ----- */

/*
* =====================================================================================
*
*       Filename:  ipconfig.cpp
*
*    Description:  基于ifconfig命令，获取、配置系统当前网络配置参数。
*
*        Version:  1.0
*        Created:  11/23/2012 11:35:52 AM HKT
*       Revision:  none
*       Compiler:  gcc
*
*         Author:   (),
*        Company:
*
* =====================================================================================
*/

#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>
#ifdef __linux__
#include <unistd.h>
#endif
#include <sys/file.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <net/if.h>
#include <sys/ioctl.h>
#include "RcsFile.h"
#include "lederror.h"

static const unsigned int IPADDR_LEN  = 15;//IP地址长度
static const unsigned int MACADDR_LEN = 17;//MAC地址长度

/**
* \brief 判断字符是否为十六进制表示字符，即0~f。
*/
bool IsHexChar(char hex)
{
return ( ( hex >= '0' && hex <= '9' )    ||
( hex >= 'a' && hex <= 'f' ) ||
( hex >= 'A' && hex <= 'F' ) );
}

int HexCharToInt(char hex)
{
int val = -1;

if( hex >= '0' && hex <= '9' )
{
val = hex - '0';
}
else if( hex >= 'a' && hex <= 'f' )
{
val = hex - 'a' + 10;
}
else if( hex >= 'A' && hex <= 'F' )
{
val = hex - 'A' + 10;
}

return val;
}

/**
* \brief 判断输入ip是否有效
*
* \return true   有效
*            false  无效
*/
bool IsIpValid(const char* pAddr)
{
if ( NULL == pAddr )
{
return false;
}
struct in_addr addr;
if ( inet_aton ( pAddr, &addr ) == 0 )
{
return false;
}

char* destIp = ( char* ) inet_ntoa ( addr );
if ( 0 != strcmp ( pAddr, destIp ) )
{
return false;
}

return true;
}

/**
* \brief 判断输入netmask字符串是否有效
*
* \param    pNetMask    表示netmask的字符串指针
*
* \return  true         有效
* \return  false         无效
*/
bool IsMaskValid(const char* pNetMask)
{
bool ret = false;

if ( !IsIpValid(pNetMask) )
{
return ret;
}

unsigned int mask = ntohl( inet_addr(pNetMask) );

//最高8位必须全为0，且不能为0xffffff
if ( mask < 0xff || mask == 0xffffffff )
{
return ret;
}

for ( int i = 23; i >= 0; --i )
{
if ( (mask & (1 << i)) > 0 )
{
continue;
}
if ( (mask << (8 + 23 - i)) > 0 )
{
ret = false;
break;
}
ret = true;
break;
}

return ret;
}

/**
* \brief 判断输入mac字符串是否有效
*
* \param    pMac    表示mac地址的字符串指针
*
* \return  true     有效
* \return  false     无效
*/
bool IsMacValid(const char* pMac)
{
if ( NULL == pMac || strlen ( pMac ) != MACADDR_LEN )
{
return false;
}

//MAC的第一个字节必须为偶数
if( HexCharToInt(*(pMac+1)) % 2 != 0 )
{
return false;
}

for ( unsigned int index = 0; index < MACADDR_LEN; ++index )
{
if ( 0 == ( ( index + 1 ) % 3 ) ) //不检查间隔为3的字符
{
continue;
}

//字符必须为十六进制表示字符，即0~f。
char val = ( * ( pMac + index ) );
if ( !IsHexChar(val) )
{
return false;
}
}

return true;
}

/**
* \brief 判断输入网关字符串是否有效
*
* \param    pGateway    表示网关地址的字符串指针
*
* \return  true     有效
* \return  false     无效
*/
bool IsGatewayValid(const char* pGateway)
{
return IsIpValid(pGateway);
}

/**
*
* \brief      获取系统eth0当前IP地址
*
* \param    pAddr    存储IP地址的内存地址，不小于16个字节。
*
* \Return  0        成功
*            else    失败
*/
int  GetSysIp(char* pAddr)
{
const char FILE_NAME[] = "/tmp/ipaddr.txt";
const char SCRIPT[]    = "ifconfig eth0 | grep inet | cut -d: -f2 | cut -d' ' -f1 > /tmp/ipaddr.txt";
FILE*       handle      = NULL;
char*       delimiter   = NULL;

if ( pAddr == NULL )
{
return RET_ERR_PARAM;
}

if ( system(SCRIPT) != 0 )
{
fprintf(stderr, "Execute command '%s'error: %s\n", SCRIPT, strerror(errno));
goto FAILED;
}

if ( (handle = fopen(FILE_NAME, "r")) != NULL )
{
fgets(pAddr, IPADDR_LEN-1, handle);
}
else
{
fprintf(stderr, "Open file %s error: %s\n", FILE_NAME, strerror(errno));
goto FAILED;
}

fclose(handle);

if ( (delimiter = strchr(pAddr, '\x0a')) != NULL )
{
*delimiter = '\0';
}

unlink(FILE_NAME);
return RET_OK;

FAILED:
unlink(FILE_NAME);
return RET_ERROR;
}

/**
*
* \brief      获取系统eth0当前子网掩码
*
* \param    pMask    存储子网掩码的内存地址，不小于16个字节。
*
* \Return  0        成功
*            else    失败
*/
int  GetSysMask(char* pMask)
{
const char FILE_NAME[] = "/tmp/netmask.txt";
const char SCRIPT[]    = "ifconfig eth0 | grep Mask | cut -dk -f2 | cut -d: -f2 > /tmp/netmask.txt";
FILE*       handle      = NULL;
char*       delimiter   = NULL;

if ( pMask == NULL )
{
return RET_ERR_PARAM;
}

if ( system(SCRIPT) != 0 )
{
fprintf(stderr, "Execute command '%s'error: %s\n", SCRIPT, strerror(errno));
goto FAILED;
}

if ( (handle = fopen(FILE_NAME, "r")) != NULL )
{
fgets(pMask, IPADDR_LEN+1, handle);
}
else
{
fprintf(stderr, "Open file %s error: %s\n", FILE_NAME, strerror(errno));
goto FAILED;
}

fclose(handle);

if ( (delimiter = strchr(pMask, '\x0a')) != NULL )
{
*delimiter = '\0';
}

unlink(FILE_NAME);
return RET_OK;

FAILED:
unlink(FILE_NAME);
return RET_ERROR;
}

/**
*
* \brief      获取系统eth0当前IP地址和子网掩码
*
* \param    pAddr    存储IP地址的内存地址，不小于16个字节。
* \param    pMask    存储子网掩码的内存地址，不小于16个字节。
*
* \Return  0        成功
*            else    失败
*/
int GetSysIpMask(char* pAddr, char* pMask)
{

const char FILE_NAME[] = "/tmp/ipmask.txt";
const char SCRIPT[]    = "ifconfig eth0 | grep -i mask > /tmp/ipmask.txt";
char       info[128]   = {0};
char       *delimiter  = NULL;
FILE       *handle     = NULL;

if ( pAddr == NULL || pMask == NULL )
{
return RET_ERR_PARAM;
}

if ( system(SCRIPT) != 0 )
{
fprintf(stderr, "Execute command '%s'error: %s\n", SCRIPT, strerror(errno));
goto FAILED;
}

if ( (handle = fopen(FILE_NAME, "r")) != NULL )
{

fread(info, 128, 1, handle);

char* ipbegin = strstr(info, "addr:");
if( ipbegin )
{
ipbegin += 5;
sscanf(ipbegin, "%s", pAddr);
}

char* maskbegin = strstr(info, "Mask:");
if( maskbegin )
{
maskbegin += 5;
sscanf(maskbegin, "%s", pMask);
}

fclose(handle);
}
else
{
fprintf(stderr, "Open file %s error: %s\n", FILE_NAME, strerror(errno));
goto FAILED;
}

if ( (delimiter = strchr(pAddr, '\x0a')) != NULL )
{
*delimiter = '\0';
}

if ( (delimiter = strchr(pMask, '\x0a')) != NULL )
{
*delimiter = '\0';
}

unlink(FILE_NAME);
return RET_OK;

FAILED:
unlink(FILE_NAME);
return RET_ERROR;
}

/**
*
* \brief      获取系统eth0 Mac地址
*
* \param    pMask    存储 Mac地址的内存地址，不小于18个字节。
*
* \Return  0        成功
*            else    失败
*/
int  GetSysMac(char* pMac)
{
const char FILE_NAME[] = "/tmp/ipmac.txt";
const char SCRIPT[]    = "ifconfig eth0 | grep HWaddr|tr -s ' '|cut -d ' ' -f 5 > /tmp/ipmac.txt";
FILE*       handle      = NULL;
char*       delimiter   = NULL;

if ( pMac == NULL )
{
return RET_ERR_PARAM;
}

if ( system(SCRIPT) != 0 )
{
fprintf(stderr, "Execute command '%s'error: %s\n", SCRIPT, strerror(errno));
goto FAILED;
}

if ( (handle = fopen(FILE_NAME, "r")) != NULL )
{
fgets(pMac, MACADDR_LEN+1, handle);
}
else
{
fprintf(stderr, "Open file %s error: %s\n", FILE_NAME, strerror(errno));
goto FAILED;
}

fclose(handle);

if ( (delimiter = strchr(pMac, '\x0a')) != NULL )
{
*delimiter = '\0';
}

unlink(FILE_NAME);
return RET_OK;

FAILED:
unlink(FILE_NAME);
return RET_ERROR;
}

/**
* \brief 获取系统网关地址。
*
* \return    RET_OK          成功
* \return     RET_ERROR   失败
*/
int GetSysGateway(char* pGateway)
{
const char FILE_NAME[] = "/tmp/ipgateway.txt";
const char SCRIPT[]    = "route  | grep default | cut -d' ' -f10 | cut -d' ' -f1 > /tmp/ipgateway.txt";
FILE*       handle      = NULL;
char*       delimiter   = NULL;

if ( pGateway == NULL )
{
return RET_ERR_PARAM;
}

if ( system(SCRIPT) != 0 )
{
fprintf(stderr, "Execute command '%s'error: %s\n", SCRIPT, strerror(errno));
goto FAILED;
}

if ( (handle = fopen(FILE_NAME, "r")) != NULL )
{
fgets(pGateway, IPADDR_LEN+1, handle);
}
else
{
fprintf(stderr, "Open file %s error: %s\n", FILE_NAME, strerror(errno));
goto FAILED;
}

fclose(handle);

if ( (delimiter = strchr(pGateway, '\x0a')) != NULL )
{
*delimiter = '\0';
}

unlink(FILE_NAME);
return RET_OK;

FAILED:
unlink(FILE_NAME);
return RET_ERROR;
}

int SetSysIp(const char* pAddr)
{
if ( !IsIpValid(pAddr) )
{
fprintf(stderr, "Input ip %s is invalid\n", pAddr);
return RET_ERROR;
}

char localip[80] = {0};

GetSysIp(localip);
if ( strcmp(localip, pAddr) == 0 )
{
return RET_OK;
}

fprintf(stderr, "[%s]: ip is %s\n", __FUNCTION__, pAddr);
sprintf(localip, "ifconfig eth0 %s up ", pAddr);
if ( system(localip) != 0 )
{
fprintf(stderr, "Execute command '%s' error: %s\n", localip, strerror(errno));
return RET_ERROR;
}

return ModifyRcs("LED_IP",pAddr);
}

int SetSysMask(const char* pMask)
{
if ( !IsMaskValid(pMask) )
{
fprintf(stderr, "Input netmask %s is invalid\n", pMask);
return RET_ERROR;
}

char netmask[80] = {0};

GetSysIp(netmask);
if ( strcmp(netmask, pMask) == 0 )
{
return RET_OK;
}

fprintf(stderr, "[%s]: netmask is %s\n", __FUNCTION__, pMask);
sprintf(netmask, "ifconfig eth0 netmask %s up ", pMask);
if ( system(netmask) != 0 )
{
fprintf(stderr, "Execute command '%s' error: %s\n", netmask, strerror(errno));
return RET_ERROR;
}

return ModifyRcs("LED_MASK",pMask);
}

int SetSysMac(const char* pMac)
{
if ( !IsMacValid(pMac) )
{
fprintf(stderr, "Input mac addr %s is invalid\n", pMac);
return RET_ERROR;
}

char mac[80] = {0};

GetSysMac(mac);
if ( strcmp(mac, pMac) == 0 )
{
return RET_OK;
}

fprintf(stderr, "[%s]: mac addr is %s\n", __FUNCTION__, pMac);

//shut down network
memset(mac, 0, sizeof(mac));
sprintf(mac, "ifconfig eth0 down");
if ( system(mac) != 0 )
{
fprintf(stderr, "Execute command '%s' error: %s\n", mac, strerror(errno));
return RET_ERROR;
}

//config mac address
memset(mac, 0, sizeof(mac));
sprintf(mac, "ifconfig eth0 hw ether %s", pMac);
if ( system(mac) != 0 )
{
fprintf(stderr, "Execute command '%s' error: %s\n", mac, strerror(errno));
return RET_ERROR;
}

//start network
memset(mac, 0, sizeof(mac));
sprintf(mac, "ifconfig eth0 up");
if ( system(mac) != 0 )
{
fprintf(stderr, "Execute command '%s' error: %s\n", mac, strerror(errno));
return RET_ERROR;
}

return ModifyRcs("LED_MAC",pMac);
}

/**
* \brief     设置ip和mask。
*
* \return    RET_OK         成功
* \return     RET_ERROR   失败
*/
int   SetSysIpMask(const char* pAddr, const char* pNetMask)
{
//判断ip和mask的有效性
if ( (!IsIpValid(pAddr)) || (!IsMaskValid(pNetMask)) )
{
fprintf(stderr, "Input ip %s or netmask %s is invalid\n", pAddr, pNetMask);
return RET_ERROR;
}

//设置ip和netmask
char script[80] = {0};
sprintf(script, "ifconfig eth0 %s netmask %s up ", pAddr, pNetMask);
if ( system(script) != 0 )
{
fprintf(stderr, "Execute command '%s' error: %s\n", script, strerror(errno));
return RET_ERROR;
}

ModifyRcs("LED_IP",pAddr);
return ModifyRcs("LED_MASK",pNetMask);
}

/**
* \brief     设置gateway。
*
* \return    RET_OK         成功
* \return     RET_ERROR   失败
*/
int   SetSysGateway(const char* pGateway)
{
if( pGateway && strlen(pGateway) == 0 )
{
//把网关删除，设为空
}
else
{
//判断gateway的有效性
if ( (!IsGatewayValid(pGateway)) )
{
fprintf(stderr, "Input Gateway %s is invalid\n", pGateway);
return RET_ERROR;
}
}

//设置gateway
char script[80] = {0};
sprintf(script, "route del default ");
if ( system(script) != 0 )
{
fprintf(stderr, "Execute command '%s' error: %s\n", script, strerror(errno));
}

if( strlen(pGateway) )
{
sprintf(script, "route add default gw %s  ", pGateway);
if ( system(script) != 0 )
{
fprintf(stderr, "Execute command '%s' error: %s\n", script, strerror(errno));
return RET_ERROR;
}
}

return ModifyRcs("LED_GATEWAY",pGateway);
}

/**
* \brief 根据IP和子网掩码获取本网段广播地址。
*/
int  GetSysBroadcast(const char* pAddr, const char* pMask, char* pBc)
{
if( !pAddr || !pMask || !pBc )
{
return RET_ERR_PARAM;
}

if( !IsIpValid(pAddr) || !IsMaskValid(pMask) )
{
return RET_ERR_PARAM;
}

unsigned int ip   = ntohl( inet_addr(pAddr) );
unsigned int mask = ntohl( inet_addr(pMask) );
unsigned int bc   = (ip & mask) | (~mask);

struct in_addr bcAddr;
bcAddr.s_addr = htonl(bc);

char *tmp = inet_ntoa(bcAddr);
memcpy(pBc, tmp, strlen(tmp));

return RET_OK;
}

/**
*
* \brief      通过广播socket获取系统eth0当前IP地址
*
* \param    pAddr    存储IP地址的内存地址，不小于16个字节。
*
* \Return  0        成功
*            else    失败
*/
int  GetSysIpBySocket(char* pAddr)
{
if ( pAddr == NULL )
{
return RET_ERR_PARAM;
}

struct sockaddr_in *sin;
struct ifreq        ifr;

int sock = socket(AF_INET,SOCK_DGRAM,0);
if(sock <= 0)
{
perror("socket error!\n");
return RET_ERROR;
}

strcpy(ifr.ifr_name,"eth0");

if(ioctl(sock,SIOCGIFADDR,&ifr) < 0)
{
perror("ioctl error\n");
close(sock);
return RET_ERROR;
}
else
{
sin = (struct sockaddr_in *)&(ifr.ifr_addr);
strcpy(pAddr, inet_ntoa(sin->sin_addr));
close(sock);
}

return RET_OK;
}

/**
*
* \brief      通过广播socket获取系统eth0当前子网掩码
*
* \param    pMask    存储子网掩码的内存地址，不小于16个字节。
*
* \Return  0        成功
*            else    失败
*/
int  GetSysMaskBySocket(char* pMask)
{
if ( pMask == NULL )
{
return RET_ERR_PARAM;
}

struct sockaddr_in *sin;
struct ifreq        ifr;

int sock = socket(AF_INET,SOCK_DGRAM,0);
if(sock <= 0)
{
perror("socket error!\n");
return RET_ERROR;
}

strcpy(ifr.ifr_name,"eth0");

if(ioctl(sock,SIOCGIFNETMASK,&ifr) < 0)
{
perror("ioctl error\n");
close(sock);
return RET_ERROR;
}
else
{
sin = (struct sockaddr_in *)&(ifr.ifr_netmask);
strcpy(pMask, inet_ntoa(sin->sin_addr));
close(sock);
}

return RET_OK;
}

/**
*
* \brief      通过广播socket获取系统eth0当前IP地址和子网掩码
*
* \param    pAddr    存储IP地址的内存地址，不小于16个字节。
* \param    pMask    存储子网掩码的内存地址，不小于16个字节。
*
* \Return  0        成功
*            else    失败
*/
int GetSysIpMaskBySocket(char* pAddr, char* pMask)
{
if ( pAddr == NULL || pMask == NULL )
{
return RET_ERR_PARAM;
}

struct sockaddr_in *sin;
struct ifreq        ifr;

int sock = socket(AF_INET,SOCK_DGRAM,0);
if(sock <= 0)
{
perror("socket error!\n");
return RET_ERROR;
}

strcpy(ifr.ifr_name,"eth0");

if(ioctl(sock,SIOCGIFADDR,&ifr) < 0)
{
perror("ioctl SIOCGIFADDR error\n");
close(sock);
return RET_ERROR;
}
else
{
sin = (struct sockaddr_in *)&(ifr.ifr_addr);
strcpy(pAddr, inet_ntoa(sin->sin_addr));
}

if(ioctl(sock,SIOCGIFNETMASK,&ifr) < 0)
{
perror("ioctl SIOCGIFNETMASK error\n");
close(sock);
return RET_ERROR;
}
else
{
sin = (struct sockaddr_in *)&(ifr.ifr_netmask);
strcpy(pMask, inet_ntoa(sin->sin_addr));

}

close(sock);
return RET_OK;
}

/**
*
* \brief      通过ioctl获取系统eth0 Mac地址
*
* \param    pMask    存储 Mac地址的内存地址，不小于18个字节。
*
* \Return  0        成功
*            else    失败
*/
int  GetSysMacBySocket(char* pMac)
{
if ( pMac == NULL )
{
return RET_ERR_PARAM;
}

struct ifreq        ifr;

int sock = socket(AF_INET,SOCK_DGRAM,0);
if(sock <= 0)
{
perror("socket error!\n");
return RET_ERROR;
}

strcpy(ifr.ifr_name,"eth0");

if(ioctl(sock,SIOCGIFHWADDR,&ifr) < 0)
{
perror("ioctl SIOCGIFHWADDR error\n");
close(sock);
return RET_ERROR;
}
else
{
sprintf(pMac, "%02x:%02x:%02x:%02x:%02x:%02x",
(unsigned char)ifr.ifr_hwaddr.sa_data[0],
(unsigned char)ifr.ifr_hwaddr.sa_data[1],
(unsigned char)ifr.ifr_hwaddr.sa_data[2],
(unsigned char)ifr.ifr_hwaddr.sa_data[3],
(unsigned char)ifr.ifr_hwaddr.sa_data[4],
(unsigned char)ifr.ifr_hwaddr.sa_data[5]);
}

close(sock);
return RET_OK;
}