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
|
/* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2
* as published by the Free Software Foundation.
*
* This program 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.
*/
#include <linux/if_arp.h>
#include <net/6lowpan.h>
#include <net/ieee802154_netdev.h>
#include "6lowpan_i.h"
static int lowpan_give_skb_to_device(struct sk_buff *skb,
struct net_device *dev)
{
skb->dev = dev->ieee802154_ptr->lowpan_dev;
skb->protocol = htons(ETH_P_IPV6);
skb->pkt_type = PACKET_HOST;
return netif_rx(skb);
}
static int
iphc_decompress(struct sk_buff *skb, const struct ieee802154_hdr *hdr)
{
u8 iphc0, iphc1;
struct ieee802154_addr_sa sa, da;
void *sap, *dap;
raw_dump_table(__func__, "raw skb data dump", skb->data, skb->len);
/* at least two bytes will be used for the encoding */
if (skb->len < 2)
return -EINVAL;
if (lowpan_fetch_skb_u8(skb, &iphc0))
return -EINVAL;
if (lowpan_fetch_skb_u8(skb, &iphc1))
return -EINVAL;
ieee802154_addr_to_sa(&sa, &hdr->source);
ieee802154_addr_to_sa(&da, &hdr->dest);
if (sa.addr_type == IEEE802154_ADDR_SHORT)
sap = &sa.short_addr;
else
sap = &sa.hwaddr;
if (da.addr_type == IEEE802154_ADDR_SHORT)
dap = &da.short_addr;
else
dap = &da.hwaddr;
return lowpan_header_decompress(skb, skb->dev, sap, sa.addr_type,
IEEE802154_ADDR_LEN, dap, da.addr_type,
IEEE802154_ADDR_LEN, iphc0, iphc1);
}
static int lowpan_rcv(struct sk_buff *skb, struct net_device *dev,
struct packet_type *pt, struct net_device *orig_dev)
{
struct ieee802154_hdr hdr;
int ret;
skb = skb_share_check(skb, GFP_ATOMIC);
if (!skb)
goto drop;
if (!netif_running(dev))
goto drop_skb;
if (skb->pkt_type == PACKET_OTHERHOST)
goto drop_skb;
if (dev->type != ARPHRD_IEEE802154)
goto drop_skb;
if (ieee802154_hdr_peek_addrs(skb, &hdr) < 0)
goto drop_skb;
/* check that it's our buffer */
if (skb->data[0] == LOWPAN_DISPATCH_IPV6) {
/* Pull off the 1-byte of 6lowpan header. */
skb_pull(skb, 1);
return lowpan_give_skb_to_device(skb, dev);
} else {
switch (skb->data[0] & 0xe0) {
case LOWPAN_DISPATCH_IPHC: /* ipv6 datagram */
ret = iphc_decompress(skb, &hdr);
if (ret < 0)
goto drop_skb;
return lowpan_give_skb_to_device(skb, dev);
case LOWPAN_DISPATCH_FRAG1: /* first fragment header */
ret = lowpan_frag_rcv(skb, LOWPAN_DISPATCH_FRAG1);
if (ret == 1) {
ret = iphc_decompress(skb, &hdr);
if (ret < 0)
goto drop_skb;
return lowpan_give_skb_to_device(skb, dev);
} else if (ret == -1) {
return NET_RX_DROP;
} else {
return NET_RX_SUCCESS;
}
case LOWPAN_DISPATCH_FRAGN: /* next fragments headers */
ret = lowpan_frag_rcv(skb, LOWPAN_DISPATCH_FRAGN);
if (ret == 1) {
ret = iphc_decompress(skb, &hdr);
if (ret < 0)
goto drop_skb;
return lowpan_give_skb_to_device(skb, dev);
} else if (ret == -1) {
return NET_RX_DROP;
} else {
return NET_RX_SUCCESS;
}
default:
break;
}
}
drop_skb:
kfree_skb(skb);
drop:
return NET_RX_DROP;
}
static struct packet_type lowpan_packet_type = {
.type = htons(ETH_P_IEEE802154),
.func = lowpan_rcv,
};
void lowpan_rx_init(void)
{
dev_add_pack(&lowpan_packet_type);
}
void lowpan_rx_exit(void)
{
dev_remove_pack(&lowpan_packet_type);
}
|
