The simplest sniffer

Here's the source code of the simplest sniffer using Winsock.

// Coded by rev __
#include <stdafx.h>
#include <winsock2.h>
#include <mstcpip.h>

// Buffer for receiving data
#define MAX_PACKET_SIZE 65535
static BYTE Buffer[MAX_PACKET_SIZE];

int _tmain(int argc, _TCHAR *argv[])
{
  WSADATA wsadata; // Initialize WinSock.
  SOCKET RawSocket; // Listening Socket
  unsigned long flag = 1; // Ôëàã PROMISC Âêë/âûêë.

  // Initialize WS2_32
  WSAStartup(MAKEWORD(2, 2), &wsadata);
  // Create RAW-socket
  RawSocket = socket(AF_INET, SOCK_RAW, IPPROTO_IP);

  // Determine host name
  char HostName[256];
  gethostname(HostName, sizeof(HostName));
  printf("HostName = %s \n", HostName);

  // Determine information from host name
  PHOSTENT pLocalHostEnt;
  pLocalHostEnt = gethostbyname(HostName);

  // Prepare buffer SockAddr with ip address of host
  SOCKADDR_IN SockAddr;
  ZeroMemory(&SockAddr, sizeof(SockAddr));
  SockAddr.sin_family = AF_INET;
  SockAddr.sin_addr.s_addr = ((in_addr*)pLocalHostEnt->h_addr_list[0])->s_addr;
  // Bind socket
  bind(RawSocket, (SOCKADDR*) &SockAddr, sizeof(SOCKADDR));

  // Switching network card in "promiscuous mode" to capture all packets
  ioctlsocket(RawSocket, SIO_RCVALL, &flag);

  // Receive IP-packets.
  while (true)
  {

    int count;

    count = recv(RawSocket, (char*)Buffer, sizeof(Buffer), 0);
    printf("Len = %d \n", count);

    // --- code for processing and recording the captured IP-packet ---
  }

  closesocket(RawSocket);
  WSACleanup();
}