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/* 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 *wdev)
{
skb->dev = wdev->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 *wdev,
struct packet_type *pt, struct net_device *orig_wdev)
{
struct ieee802154_hdr hdr;
struct net_device *ldev;
int ret;
if (wdev->type != ARPHRD_IEEE802154)
goto drop;
ldev = wdev->ieee802154_ptr->lowpan_dev;
if (!ldev || !netif_running(ldev))
goto drop;
skb = skb_share_check(skb, GFP_ATOMIC);
if (!skb)
goto drop;
if (skb->pkt_type == PACKET_OTHERHOST)
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, wdev);
} 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, wdev);
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, wdev);
} 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, wdev);
} 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);
}
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