grub/grub-core/net/udp.c

#include <grub/net.h>
#include <grub/net/udp.h>
#include <grub/net/ip.h>
#include <grub/net/netbuff.h>
#include <grub/time.h>

grub_err_t
grub_net_send_udp_packet (const grub_net_socket_t socket,
			  struct grub_net_buff *nb)
{
  struct udphdr *udph;
  grub_err_t err;

  err = grub_netbuff_push (nb, sizeof (*udph));
  if (err)
    return err;

  udph = (struct udphdr *) nb->data;
  udph->src = grub_cpu_to_be16 (socket->in_port);
  udph->dst = grub_cpu_to_be16 (socket->out_port);

  /* No chechksum. */
  udph->chksum = 0;
  udph->len = grub_cpu_to_be16 (nb->tail - nb->data);

  return grub_net_send_ip_packet (socket->inf, &(socket->out_nla), nb);
}

grub_err_t
grub_net_recv_udp_packet (struct grub_net_buff * nb,
			  struct grub_net_network_level_interface * inf)
{
  struct udphdr *udph;
  grub_net_socket_t sock;
  udph = (struct udphdr *) nb->data;
  grub_netbuff_pull (nb, sizeof (*udph));

  FOR_NET_SOCKETS (sock)
  {
    if (grub_be_to_cpu16 (udph->dst) == sock->in_port
	&& inf == sock->inf && sock->app)
      {
	if (sock->status == 0)
	  sock->out_port = grub_be_to_cpu16 (udph->src);

	/* App protocol remove its own reader.  */
	sock->app->read (sock, nb);

	/* If there is data, puts packet in socket list. */
	if ((nb->tail - nb->data) > 0)
	  grub_net_put_packet (&sock->packs, nb);
	else
	  grub_netbuff_free (nb);
	return GRUB_ERR_NONE;
      }
  }
  if (grub_be_to_cpu16 (udph->dst) == 68)
    grub_net_process_dhcp (nb, inf->card);
  grub_netbuff_free (nb);
  return GRUB_ERR_NONE;
}