grub/grub-core/net/ethernet.c

135 lines
3.5 KiB
C

/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2010,2011 Free Software Foundation, Inc.
*
* GRUB is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* GRUB is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with GRUB. If not, see <http://www.gnu.org/licenses/>.
*/
#include <grub/misc.h>
#include <grub/mm.h>
#include <grub/net/ethernet.h>
#include <grub/net/ip.h>
#include <grub/net/arp.h>
#include <grub/net/netbuff.h>
#include <grub/net.h>
#include <grub/time.h>
#include <grub/net/arp.h>
#define LLCADDRMASK 0x7f
struct etherhdr
{
grub_uint8_t dst[6];
grub_uint8_t src[6];
grub_uint16_t type;
} GRUB_PACKED;
struct llchdr
{
grub_uint8_t dsap;
grub_uint8_t ssap;
grub_uint8_t ctrl;
} GRUB_PACKED;
struct snaphdr
{
grub_uint8_t oui[3];
grub_uint16_t type;
} GRUB_PACKED;
grub_err_t
send_ethernet_packet (struct grub_net_network_level_interface *inf,
struct grub_net_buff *nb,
grub_net_link_level_address_t target_addr,
grub_net_ethertype_t ethertype)
{
struct etherhdr *eth;
grub_err_t err;
COMPILE_TIME_ASSERT (sizeof (*eth) < GRUB_NET_MAX_LINK_HEADER_SIZE);
err = grub_netbuff_push (nb, sizeof (*eth));
if (err)
return err;
eth = (struct etherhdr *) nb->data;
grub_memcpy (eth->dst, target_addr.mac, 6);
grub_memcpy (eth->src, inf->hwaddress.mac, 6);
eth->type = grub_cpu_to_be16 (ethertype);
if (!inf->card->opened)
{
err = GRUB_ERR_NONE;
if (inf->card->driver->open)
err = inf->card->driver->open (inf->card);
if (err)
return err;
inf->card->opened = 1;
}
return inf->card->driver->send (inf->card, nb);
}
grub_err_t
grub_net_recv_ethernet_packet (struct grub_net_buff *nb,
struct grub_net_card *card)
{
struct etherhdr *eth;
struct llchdr *llch;
struct snaphdr *snaph;
grub_net_ethertype_t type;
grub_net_link_level_address_t hwaddress;
grub_net_link_level_address_t src_hwaddress;
grub_err_t err;
eth = (struct etherhdr *) nb->data;
type = grub_be_to_cpu16 (eth->type);
err = grub_netbuff_pull (nb, sizeof (*eth));
if (err)
return err;
if (type <= 1500)
{
llch = (struct llchdr *) nb->data;
type = llch->dsap & LLCADDRMASK;
if (llch->dsap == 0xaa && llch->ssap == 0xaa && llch->ctrl == 0x3)
{
err = grub_netbuff_pull (nb, sizeof (*llch));
if (err)
return err;
snaph = (struct snaphdr *) nb->data;
type = snaph->type;
}
}
hwaddress.type = GRUB_NET_LINK_LEVEL_PROTOCOL_ETHERNET;
grub_memcpy (hwaddress.mac, eth->dst, sizeof (hwaddress.mac));
src_hwaddress.type = GRUB_NET_LINK_LEVEL_PROTOCOL_ETHERNET;
grub_memcpy (src_hwaddress.mac, eth->src, sizeof (src_hwaddress.mac));
switch (type)
{
/* ARP packet. */
case GRUB_NET_ETHERTYPE_ARP:
grub_net_arp_receive (nb, card);
grub_netbuff_free (nb);
return GRUB_ERR_NONE;
/* IP packet. */
case GRUB_NET_ETHERTYPE_IP:
case GRUB_NET_ETHERTYPE_IP6:
return grub_net_recv_ip_packets (nb, card, &hwaddress, &src_hwaddress);
}
grub_netbuff_free (nb);
return GRUB_ERR_NONE;
}