基于网卡序号双网卡数据共享(网卡转发)
基于网卡序号：ifr.ifr_ifindex;
实现网卡之间的数据转发
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#define RET_ERROR -1
#define RET_FAIL 0
#define RET_SUCCESS 1
#define NIC1_NIC_IND 1
#define NIC2_NIC_IND 2
int g_eth1_index = 0;
int g_eth2_index = 0;
const char ETH_NIC_DEV1[16] = "eth0";
const char ETH_NIC_DEV2[16] = "eth1";
/*
函数名称：inline int active_dev( const int sockFd, const char * dev)
功能说明：激活网口
输入参数：
sockFd:套接字描述符
dev：对应的网口
输出参数：无
返回值：
int 成功返回1，失败返回0
关系函数：socket（）
线程安全：否
*/
static int active_dev(const int sockFd, const char* dev)
{
int ret;
struct ifreq req;
bzero(&req, sizeof(struct ifreq));
strncpy(req.ifr_name, dev, sizeof(req.ifr_name));
ret = ioctl(sockFd, SIOCGIFFLAGS, &req);
if (ret == -1)
{
return(RET_FAIL);
}
req.ifr_flags |= IFF_UP;
ret = ioctl(sockFd, SIOCSIFFLAGS, &req);
if (ret == -1)
{
return(RET_FAIL);
}
return(RET_SUCCESS);
}
/*
函数名称：inline int open_socket( int & sockFd)
功能说明：新建套接字。
输入参数：sockFd:套接字描述符
输出参数：无
返回值：
int 成功返回新建的套接字描述符，失败返回0
关系函数：无
线程安全：否
*/
int open_socket(void)
{
struct ifreq ifr;
int s;
int ret;
int sockFd = 0;
sockFd = socket(PF_PACKET, SOCK_RAW, htons(ETH_P_ALL));
if (sockFd < 0)
{
exit(0);
}
ret = active_dev(sockFd, ETH_NIC_DEV1);
if (ret == RET_FAIL)
{
close(sockFd);
exit(0);
}
strncpy(ifr.ifr_name, ETH_NIC_DEV1, sizeof(ifr.ifr_name));
s = ioctl(sockFd, SIOCGIFFLAGS, &ifr);
if (s < 0)
{
close(sockFd);
exit(0);
}
ifr.ifr_flags |= IFF_PROMISC;
ifr.ifr_flags |= IFF_UP;
s = ioctl(sockFd, SIOCSIFFLAGS, &ifr);
if (s < 0)
{
}
ioctl(sockFd, SIOCGIFINDEX, &ifr);
//sl.sll_ifindex = ifr.ifr_ifindex;
g_eth1_index = ifr.ifr_ifindex;
ret = active_dev(sockFd, ETH_NIC_DEV2);
if (ret == RET_FAIL)
{
close(sockFd);
exit(0);
}
strncpy(ifr.ifr_name, ETH_NIC_DEV2, sizeof(ifr.ifr_name));
s = ioctl(sockFd, SIOCGIFFLAGS, &ifr);
if (s < 0)
{
close(sockFd);
exit(0);
}
ifr.ifr_flags |= IFF_PROMISC;
ifr.ifr_flags |= IFF_UP;
s = ioctl(sockFd, SIOCSIFFLAGS, &ifr);
if (s < 0)
{
}
ioctl(sockFd, SIOCGIFINDEX, &ifr);
//sl.sll_ifindex = ifr.ifr_ifindex;
g_eth2_index = ifr.ifr_ifindex;
return(sockFd);
}
/*
函数名称：inline int set_sockopt( const int sockFd)
功能说明：对新建的套接字进行设置。
输入参数：
sockFd:套接字描述符
输出参数：无
返回值：
int 成功返回0，失败返回0
关系函数：无
线程安全：否
*/
int set_sockopt(const int sockFd)
{
int optval = 0;
int optlen = 0;
int ret;
ret = getsockopt(sockFd, SOL_SOCKET, SO_RCVBUF, &optval, (socklen_t*)&optlen);
if (ret < 0)
{
return(RET_FAIL);
}
optval = 1024 * 128;// * 16;
optlen = sizeof(optval);
ret = setsockopt(sockFd, SOL_SOCKET, SO_RCVBUF, &optval, (socklen_t)optlen);
if (ret < 0)
{
return(RET_FAIL);
}
ret = getsockopt(sockFd, SOL_SOCKET, SO_RCVBUF, &optval, (socklen_t*)&optlen);
if (ret < 0)
{
return(RET_FAIL);
}
optval = 1024 * 512;// * 8;
optlen = sizeof(optval);
ret = setsockopt(sockFd, SOL_SOCKET, SO_SNDBUF, &optval, (socklen_t)optlen);
if (ret < 0)
{
return(RET_FAIL);
}
ret = getsockopt(sockFd, SOL_SOCKET, SO_SNDBUF, &optval, (socklen_t*)&optlen);
if (ret < 0)
{
return(RET_FAIL);
}
return(RET_SUCCESS);
}
/*
函数名称：int recv_via_dev( const int sockFd, char & devInd,char * data, const
int len)
功能说明：封装的接收函数
输入参数：
sockFd:套接字描述符
devInd:网口标识
data:接收的数据
Len：接收数据的长度
输出参数：无
返回值：int 成功返回1，失败返回0
关系函数：无
线程安全：是
*/
int recv_via_dev(const int sockFd, int* devInd, char* data, int len)
{
int ret = 0;
struct sockaddr_ll sa;
socklen_t sz = sizeof(sa);
ret = recvfrom(sockFd, data, len, 0, (struct sockaddr*)&sa, &sz); //function defined in system
if (ret == -1)
{
return -1;
}
if (sa.sll_ifindex == g_eth1_index)
{
*devInd = NIC1_NIC_IND;
}
else if (sa.sll_ifindex == g_eth2_index)
{
*devInd = NIC2_NIC_IND;
}
else
{
return -1;
}
return(ret);
}
/*
函数名称：int send_via_dev( const int sockFd, const char devInd, char * & data,
int & len, unsigned short vlanid=0)
功能说明：封装的发送函数
输入参数：
sockFd:套接字描述符
devInd:网口标识
data:发送的数据
Len：发送数据的长度
vlanid:vlan标识
输出参数：无
返回值：int 成功返回1，失败返回0
关系函数：无
线程安全：是
*/
int send_via_dev(const int sockFd, int devInd, char* data, int len)
{
int ret = 0;
struct sockaddr_ll sa;
sa.sll_family = AF_INET;
memcpy(sa.sll_addr, data, 6);
sa.sll_halen = 6;
if (devInd == NIC1_NIC_IND)
{
sa.sll_ifindex = g_eth1_index;
}
else if (devInd == NIC2_NIC_IND)
{
sa.sll_ifindex = g_eth2_index;
}
else
{
return -1;
}
ret = sendto(sockFd, data, len, 0, (struct sockaddr*)&sa, sizeof(sa));
if (ret < 0)
{
}
return(ret);
}
int main(void)
{
char data[1500] = {0};
int sockFd = open_socket();
int devInd = 0;
int recvLen = 0;
struct ethhdr * eth;
set_sockopt(sockFd);
while(1)
{
recvLen = recv_via_dev(sockFd, &devInd, data, 1500);
if (recvLen >= 0)
{
//eth = (struct ethhdr*)data;
//printf("port eth%d recv proto %x\n", devInd, ntohs(eth->h_proto));
if (NIC1_NIC_IND == devInd)
{
devInd = NIC2_NIC_IND;
}
else if (NIC2_NIC_IND == devInd)
{
devInd = NIC1_NIC_IND;
}
send_via_dev(sockFd, devInd, data, recvLen);
}
//fflush(stdout);
//fflush(stderr);
}
return 0;
}