pingxelflut/net_socket.cpp

#include "net_socket.hpp"
#include <linux/in6.h>
#include <iostream>
#include <linux/ip.h>
#include <linux/in6.h>

namespace net {
  net_socket::net_socket(const std::string& iface){
    /* Open PF_PACKET socket, listening for EtherType ETHER_TYPE */
    if ((sockfd = socket(PF_PACKET, SOCK_RAW, htons(ETH_P_ALL))) == -1) {
      perror("listener: socket");
      throw;
    }

    /* Set interface to promiscuous mode - do we need to do this every time? */
    // strncpy(ifopts.ifr_name, iface.c_str(), IFNAMSIZ - 1);
    ioctl(sockfd, SIOCGIFFLAGS, &ifopts);
    ifopts.ifr_flags |= IFF_PROMISC;
    ioctl(sockfd, SIOCSIFFLAGS, &ifopts);
    /* Allow the socket to be reused - incase connection is closed prematurely */
    if (setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, &sockopt, sizeof sockopt) ==
        -1) {
      perror("setsockopt");
      close(sockfd);
      exit(EXIT_FAILURE);
    }
    /* Bind to device */
    if (setsockopt(sockfd, SOL_SOCKET, SO_BINDTODEVICE, iface.c_str(), IFNAMSIZ - 1) ==
        -1) {
      perror("SO_BINDTODEVICE");
      close(sockfd);
      exit(EXIT_FAILURE);
    }
#ifndef NET_PREFIX
    my_prefix = {{0xfc00, 0x0000, 0x0000, 0x0000}};
#else
    my_prefix = {NET_PREFIX};
#endif

  }

  types::pixel net_socket::recv(){
    bool pixel_valid = false;
    while(!pixel_valid){
      numbytes = recvfrom(sockfd, buf, BUF_SIZ, 0, NULL, NULL);
      // std::array<uint8_t, 6> recv_mac;
      // std::copy(std::begin(eh->ether_dhost), std::end(eh->ether_dhost), std::begin(recv_mac));
      if (iph->version != 6) {
        continue;
      }
      /* Get source IP */
      // memcpy(&((struct sockaddr_in6 *)&their_addr)->sin6_addr.s6_addr,
      //        &((struct ipv6hdr *)iph)->saddr, sizeof(struct in6_addr));
      /* Get dest IP */
      memcpy(&((struct sockaddr_in6 *)&our_addr)->sin6_addr.s6_addr,
             &((struct ipv6hdr *)iph)->daddr, sizeof(struct in6_addr));
      std::array<uint16_t, 4> recv_prefix;
      for (size_t i=0; i<4; ++i){
        recv_prefix[i] = ntohs(((struct sockaddr_in6 *)&our_addr)->sin6_addr.s6_addr16[i]);
      }
      if (my_prefix != recv_prefix){
        continue;
      }
      pixel_valid = true;
    }
    return types::pixel((uint8_t *)&(((struct sockaddr_in6 *)&our_addr)->sin6_addr.s6_addr) + 8);
  }
    /* Look up my device IP addr if possible */
}