arch/all-pc/boot/grub2-aros/grub-core/net/ethernet.c

   1 /*
   2  *  GRUB  --  GRand Unified Bootloader
   3  *  Copyright (C) 2010,2011  Free Software Foundation, Inc.
   4  *
   5  *  GRUB is free software: you can redistribute it and/or modify
   6  *  it under the terms of the GNU General Public License as published by
   7  *  the Free Software Foundation, either version 3 of the License, or
   8  *  (at your option) any later version.
   9  *
  10  *  GRUB is distributed in the hope that it will be useful,
  11  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  *  GNU General Public License for more details.
  14  *
  15  *  You should have received a copy of the GNU General Public License
  16  *  along with GRUB.  If not, see <http://www.gnu.org/licenses/>.
  17  */
  18
  19 #include <grub/misc.h>
  20 #include <grub/mm.h>
  21 #include <grub/net/ethernet.h>
  22 #include <grub/net/ip.h>
  23 #include <grub/net/arp.h>
  24 #include <grub/net/netbuff.h>
  25 #include <grub/net.h>
  26 #include <grub/time.h>
  27 #include <grub/net/arp.h>
  28
  29 #define LLCADDRMASK 0x7f
  30
  31 struct etherhdr
  32 {
  33   grub_uint8_t dst[6];
  34   grub_uint8_t src[6];
  35   grub_uint16_t type;
  36 } GRUB_PACKED;
  37
  38 struct llchdr
  39 {
  40   grub_uint8_t dsap;
  41   grub_uint8_t ssap;
  42   grub_uint8_t ctrl;
  43 } GRUB_PACKED;
  44
  45 struct snaphdr
  46 {
  47   grub_uint8_t oui[3];
  48   grub_uint16_t type;
  49 } GRUB_PACKED;
  50
  51 grub_err_t
  52 send_ethernet_packet (struct grub_net_network_level_interface *inf,
  53                       struct grub_net_buff *nb,
  54                       grub_net_link_level_address_t target_addr,
  55                       grub_net_ethertype_t ethertype)
  56 {
  57   struct etherhdr *eth;
  58   grub_err_t err;
  59
  60   COMPILE_TIME_ASSERT (sizeof (*eth) < GRUB_NET_MAX_LINK_HEADER_SIZE);
  61
  62   err = grub_netbuff_push (nb, sizeof (*eth));
  63   if (err)
  64     return err;
  65   eth = (struct etherhdr *) nb->data;
  66   grub_memcpy (eth->dst, target_addr.mac, 6);
  67   grub_memcpy (eth->src, inf->hwaddress.mac, 6);
  68
  69   eth->type = grub_cpu_to_be16 (ethertype);
  70   if (!inf->card->opened)
  71     {
  72       err = GRUB_ERR_NONE;
  73       if (inf->card->driver->open)
  74         err = inf->card->driver->open (inf->card);
  75       if (err)
  76         return err;
  77       inf->card->opened = 1;
  78     }
  79   return inf->card->driver->send (inf->card, nb);
  80 }
  81
  82 grub_err_t
  83 grub_net_recv_ethernet_packet (struct grub_net_buff *nb,
  84                                struct grub_net_card *card)
  85 {
  86   struct etherhdr *eth;
  87   struct llchdr *llch;
  88   struct snaphdr *snaph;
  89   grub_net_ethertype_t type;
  90   grub_net_link_level_address_t hwaddress;
  91   grub_net_link_level_address_t src_hwaddress;
  92   grub_err_t err;
  93
  94   eth = (struct etherhdr *) nb->data;
  95   type = grub_be_to_cpu16 (eth->type);
  96   err = grub_netbuff_pull (nb, sizeof (*eth));
  97   if (err)
  98     return err;
  99
 100   if (type <= 1500)
 101     {
 102       llch = (struct llchdr *) nb->data;
 103       type = llch->dsap & LLCADDRMASK;
 104
 105       if (llch->dsap == 0xaa && llch->ssap == 0xaa && llch->ctrl == 0x3)
 106         {
 107           err = grub_netbuff_pull (nb, sizeof (*llch));
 108           if (err)
 109             return err;
 110           snaph = (struct snaphdr *) nb->data;
 111           type = snaph->type;
 112         }
 113     }
 114
 115   hwaddress.type = GRUB_NET_LINK_LEVEL_PROTOCOL_ETHERNET;
 116   grub_memcpy (hwaddress.mac, eth->dst, sizeof (hwaddress.mac));
 117   src_hwaddress.type = GRUB_NET_LINK_LEVEL_PROTOCOL_ETHERNET;
 118   grub_memcpy (src_hwaddress.mac, eth->src, sizeof (src_hwaddress.mac));
 119
 120   switch (type)
 121     {
 122       /* ARP packet. */
 123     case GRUB_NET_ETHERTYPE_ARP:
 124       grub_net_arp_receive (nb, card);
 125       grub_netbuff_free (nb);
 126       return GRUB_ERR_NONE;
 127       /* IP packet.  */
 128     case GRUB_NET_ETHERTYPE_IP:
 129     case GRUB_NET_ETHERTYPE_IP6:
 130       return grub_net_recv_ip_packets (nb, card, &hwaddress, &src_hwaddress);
 131     }
 132   grub_netbuff_free (nb);
 133   return GRUB_ERR_NONE;
 134 }