1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
|
/*
* 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 = 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_memcpy ((char *) nb->data + etherhdr_size - 6, &vlantag_id, 2);
grub_memcpy ((char *) nb->data + etherhdr_size - 4, (char *) &(inf->vlantag), 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) == VLANTAG_IDENTIFIER)
{
vlantag = 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;
}
|
