問題描述

我正在用混雜模式編寫一個帶有原始套接字的程序，我需要原始套接字而不是嗅探我發送的數據包.我只需要通過以太網 rx 線(而不是 tx 線)讀取數據.可能嗎?

I am writing a program with a Raw Socket in promiscuous mode and I need the raw socket not sniff the packet I send. I need to read only the data over the ethernet rx wire (not the tx wire). It's posible?

非常感謝.

推薦答案

解決方案是查看讀取的數據包是否為 PACKET_OUTGOING.使用此選項，您可以區分放入以太網 tx 線的數據包和從 rx 線讀取的數據包.

The solution is to look in the read packet if it is a PACKET_OUTGOING. Using this option you can diference the packet you put in the ethernet tx wire and the packet you read from the rx wire.

以混雜模式打開套接字:

Open the Socket in promiscuous mode:

char* i = "eth0";
int fd;
struct ifreq ifr;
struct sockaddr_ll interfaceAddr;
struct packet_mreq mreq;

if ((fd = socket(PF_PACKET,SOCK_RAW,htons(ETH_P_ALL))) < 0)
    return -1;

memset(&interfaceAddr,0,sizeof(interfaceAddr));
memset(&ifr,0,sizeof(ifr));
memset(&mreq,0,sizeof(mreq));

memcpy(&ifr.ifr_name,i,IFNAMSIZ);
ioctl(fd,SIOCGIFINDEX,&ifr);

interfaceAddr.sll_ifindex = ifr.ifr_ifindex;
interfaceAddr.sll_family = AF_PACKET;

if (bind(fd, (struct sockaddr *)&interfaceAddr,sizeof(interfaceAddr)) < 0)
    return -2;


mreq.mr_ifindex = ifr.ifr_ifindex;
mreq.mr_type = PACKET_MR_PROMISC;
mreq.mr_alen = 6;

if (setsockopt(fd,SOL_PACKET,PACKET_ADD_MEMBERSHIP,
     (void*)&mreq,(socklen_t)sizeof(mreq)) < 0)
        return -3;
//...

并閱讀.現在，我們可以區分 Rx 和 Tx 以太網線:

And read. Now, We can differentiate between the Rx and Tx ethernet wire:

unsigned char buf[1500];
struct sockaddr_ll addr;
socklen_t addr_len = sizeof(addr);
n = recvfrom(fd, buf, 2000, 0, (struct sockaddr*)&addr, &addr_len);
if (n <= 0)
{
    //Error reading
}
else if (addr.sll_pkttype == PACKET_OUTGOING)
{
    //The read data are not writing by me.
    //Use only this data to copy in the other network.
}

這就是全部.使用它我不會讀取我寫的數據.當我將網絡 1 幀復制到網絡 2 并將網絡 2 幀復制到網絡 1 時，我避免了循環.

And it's all. Using it I don't read the data I write. I avoid the loop when I copy the network 1 frames to network 2 and the network 2 frames to network 1.

這篇關于原始套接字混雜模式不嗅探我寫的內容的文章就介紹到這了，希望我們推薦的答案對大家有所幫助，也希望大家多多支持html5模板網！