C++ Sockets: Enabling Promiscuous Mode in Windows

Question

I'm trying to modify my current socketing program to capture packets in promiscuous. What I currently have is able to capture packets normally. I've seen other answer for how to do this on Linux but I need to find a way to accomplish this on Windows.

Here is my code:

int main(int argc, char const *argv[])
{
    SOCKET s;                       //The bound socket
    struct sockaddr_in server;
    int recv_len;                   //Size of received data
    char udpbuf[BUFLEN];            //A buffer for the incoming data.
    float data;                     //The data in the packet

//Create a socket
if ((s = socket(AF_INET, SOCK_RAW, 0)) == INVALID_SOCKET)
{
    printf("Could not create socket : %d", WSAGetLastError());
}
printf("Socket created.\n");

//Prepare the sockaddr_in structure
server.sin_family = AF_INET;
server.sin_addr.s_addr = inet_addr(ADDR);
server.sin_port = htons(PORT);

//Bind socket to address
if (bind(s, (struct sockaddr *)&server, sizeof(server)) == SOCKET_ERROR)
{
    printf("Bind failed with error code : %d", WSAGetLastError());
    exit(EXIT_FAILURE);
}
puts("Bind done\n");

while (true)
{
    //Block statment. Code will wait until it detect packets.
    if ((recv_len = recvfrom(s, udpbuf, BUFLEN, 0, 0, 0)) == SOCKET_ERROR)
    {
        printf("recvfrom() failed with error code : %d", WSAGetLastError());
        exit(EXIT_FAILURE);
    }

return 0;
}

Answer 1

I'd recommend you to use the winpcap library. See www.winpcap.org. They have comprehensive documentation and examples on how to do this: https://www.winpcap.org/docs/docs_412/html/group__wpcap__tut3.html

E.g. Wireshark uses winpcap on windows.

Answer 2

Base on Remy Lebeau answer. I finially got the full working code. You will need #cgo LDFLAGS: -lWs2_32 if you are using cgo with golang.(It works on in cgo with golang and mingw-w64)

#include "winsock2.h"
#include "windows.h"
#include "Mstcpip.h"
#include <stdio.h>

#define BUFLEN 65536
#define ADDR "192.168.100.2" // change it to your ip on this machine
#define PORT 0
int main(int argc, char const *argv[]){
    WSADATA wsa;
    SOCKET s;                       //The bound socket
    struct sockaddr_in server;
    int recv_len;                   //Size of received data
    char udpbuf[BUFLEN];            //A buffer for the incoming data.
    //Initialize Winsock
    int err = WSAStartup(MAKEWORD(2,0), &wsa);
    if (err != 0){
        printf("Could not initialize Winsock : %d", err);
        exit(EXIT_FAILURE);
    }
    //Create a socket
    if ((s = socket(AF_INET, SOCK_RAW, IPPROTO_IP)) == INVALID_SOCKET){
        printf("Could not create socket : %d", WSAGetLastError());
        WSACleanup();
        exit(EXIT_FAILURE);
    }
    printf("Socket created.\n");
    //Prepare the sockaddr_in structure
    memset(&server, 0, sizeof(server));
    server.sin_family = AF_INET;
    server.sin_addr.s_addr = inet_addr(ADDR);
    server.sin_port = htons(PORT);
    //Bind socket to address
    if (bind(s, (struct sockaddr *)&server, sizeof(server)) == SOCKET_ERROR){
       printf("Bind failed with error code : %d", WSAGetLastError());
       closesocket(s);
       WSACleanup();
       exit(EXIT_FAILURE);
    }
    puts("Bind done\n");
    // enable promiscuous mode
    DWORD dwValue = RCVALL_ON;
    DWORD dwBytesReturned = 0;
    if (WSAIoctl(s, SIO_RCVALL, &dwValue, sizeof(dwValue), NULL, 0, &dwBytesReturned, NULL, NULL) == SOCKET_ERROR){
        printf("Ioctl failed with error code : %d", WSAGetLastError());
        closesocket(s);
        WSACleanup();
        exit(EXIT_FAILURE);
    }
    puts("Ioctl done\n");
    while (1){
        //Block statment. Code will wait until it detect packets.
        if ((recv_len = recvfrom(s, udpbuf, BUFLEN, 0, 0, 0)) == SOCKET_ERROR){
            printf("recvfrom() failed with error code : %d", WSAGetLastError());
            closesocket(s);
            WSACleanup();
            exit(EXIT_FAILURE);
        }
        printf("recvfrom() get %d, ",recv_len);
        for (int i = 0; i < recv_len; i++){
            printf("%02X", udpbuf[i]);
        }
        puts("\n");
    }
    closesocket(s);
    WSACleanup();
    return 0;
}