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/*
* 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/env.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;
grub_uint8_t etherhdr_size;
grub_uint16_t vlantag_id = grub_cpu_to_be16_compile_time (VLANTAG_IDENTIFIER);
etherhdr_size = sizeof (*eth);
COMPILE_TIME_ASSERT (sizeof (*eth) + 4 < GRUB_NET_MAX_LINK_HEADER_SIZE);
/* Increase ethernet header in case of vlantag */
if (inf->vlantag != 0)
etherhdr_size += 4;
err = grub_netbuff_push (nb, etherhdr_size);
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;
}
/* Check and add a vlan-tag if needed. */
if (inf->vlantag != 0)
{
/* Move eth type to the right */
grub_memcpy ((char *) nb->data + etherhdr_size - 2,
(char *) nb->data + etherhdr_size - 6, 2);
/* Add the tag in the middle */
grub_uint16_t vlan = grub_cpu_to_be16 (inf->vlantag);
grub_memcpy ((char *) nb->data + etherhdr_size - 6, &vlantag_id, 2);
grub_memcpy ((char *) nb->data + etherhdr_size - 4, &vlan, 2);
}
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;
grub_uint8_t etherhdr_size = sizeof (*eth);
grub_uint16_t vlantag = 0;
/* Check if a vlan-tag is present. If so, the ethernet header is 4 bytes */
/* longer than the original one. The vlantag id is extracted and the header */
/* is reseted to the original size. */
if (grub_get_unaligned16 (nb->data + etherhdr_size - 2) == grub_cpu_to_be16_compile_time (VLANTAG_IDENTIFIER))
{
vlantag = grub_be_to_cpu16 (grub_get_unaligned16 (nb->data + etherhdr_size));
etherhdr_size += 4;
/* Move eth type to the original position */
grub_memcpy((char *) nb->data + etherhdr_size - 6,
(char *) nb->data + etherhdr_size - 2, 2);
}
eth = (struct etherhdr *) nb->data;
type = grub_be_to_cpu16 (eth->type);
err = grub_netbuff_pull (nb, etherhdr_size);
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, &vlantag);
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,
&vlantag);
}
grub_netbuff_free (nb);
return GRUB_ERR_NONE;
}
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