grub/grub-core/net/ip.c
2011-04-01 05:42:34 -03:00

100 lines
2.2 KiB
C

#include <grub/net/ip.h>
#include <grub/misc.h>
#include <grub/net/arp.h>
#include <grub/net/udp.h>
#include <grub/net/ethernet.h>
#include <grub/net.h>
#include <grub/net/netbuff.h>
#include <grub/mm.h>
grub_uint16_t
ipchksum(void *ipv, int len)
{
grub_uint16_t *ip = (grub_uint16_t *)ipv;
grub_uint32_t sum = 0;
len >>= 1;
while (len--)
{
sum += grub_be_to_cpu16 (*(ip++));
if (sum > 0xFFFF)
sum -= 0xFFFF;
}
return grub_cpu_to_be16 ((~sum) & 0x0000FFFF);
}
grub_err_t
grub_net_send_ip_packet (struct grub_net_network_level_interface *inf,
const grub_net_network_level_address_t *target,
struct grub_net_buff *nb)
{
struct iphdr *iph;
static int id = 0x2400;
grub_net_link_level_address_t ll_target_addr;
grub_err_t err;
grub_netbuff_push (nb, sizeof(*iph));
iph = (struct iphdr *) nb->data;
iph->verhdrlen = ((4 << 4) | 5);
iph->service = 0;
iph->len = grub_cpu_to_be16 (nb->tail - nb-> data);
iph->ident = grub_cpu_to_be16 (++id);
iph->frags = 0;
iph->ttl = 0xff;
iph->protocol = 0x11;
iph->src = inf->address.ipv4;
iph->dest = target->ipv4;
iph->chksum = 0 ;
iph->chksum = ipchksum((void *)nb->data, sizeof(*iph));
/* Determine link layer target address via ARP. */
err = grub_net_arp_resolve (inf, target, &ll_target_addr);
if (err)
return err;
return send_ethernet_packet (inf, nb, ll_target_addr, GRUB_NET_ETHERTYPE_IP);
}
/*
static int
ip_filter (struct grub_net_buff *nb)
{
struct iphdr *iph = (struct iphdr *) nb->data;
grub_err_t err;
if (nb->end - nb->data < (signed) sizeof (*iph))
return 0;
if (iph->protocol != 0x11 ||
iph->dest != inf->address.ipv4)
return 0;
grub_netbuff_pull (nb, sizeof (iph));
err = grub_net_put_packet (&inf->nl_pending, nb);
if (err)
{
grub_print_error ();
return 0;
}
return 1;
}
*/
grub_err_t
grub_net_recv_ip_packets (struct grub_net_buff *nb)
{
struct iphdr *iph = (struct iphdr *) nb->data;
grub_netbuff_pull (nb, sizeof (*iph));
switch (iph->protocol)
{
case IP_UDP:
return grub_net_recv_udp_packet (nb);
break;
default:
grub_netbuff_free (nb);
break;
}
return GRUB_ERR_NONE;
}