linux/net/ieee802154/6lowpan_rtnl.c
Phoebe Buckheister b70ab2e87f ieee802154: enforce consistent endianness in the 802.15.4 stack
Enable sparse warnings about endianness, replace the remaining fields
regarding network operations without explicit endianness annotations
with such that are annotated, and propagate this through the entire
stack.

Uses of ieee802154_addr_sa are not changed yet, this patch is only
concerned with all other fields (such as address filters, operation
parameters and the likes).

Signed-off-by: Phoebe Buckheister <phoebe.buckheister@itwm.fraunhofer.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-14 22:15:26 -04:00

664 lines
17 KiB
C

/* Copyright 2011, Siemens AG
* written by Alexander Smirnov <alex.bluesman.smirnov@gmail.com>
*/
/* Based on patches from Jon Smirl <jonsmirl@gmail.com>
* Copyright (c) 2011 Jon Smirl <jonsmirl@gmail.com>
*
* 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.
*/
/* Jon's code is based on 6lowpan implementation for Contiki which is:
* Copyright (c) 2008, Swedish Institute of Computer Science.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the Institute nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <linux/bitops.h>
#include <linux/if_arp.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/netdevice.h>
#include <net/af_ieee802154.h>
#include <net/ieee802154.h>
#include <net/ieee802154_netdev.h>
#include <net/6lowpan.h>
#include <net/ipv6.h>
#include "reassembly.h"
static LIST_HEAD(lowpan_devices);
/* private device info */
struct lowpan_dev_info {
struct net_device *real_dev; /* real WPAN device ptr */
struct mutex dev_list_mtx; /* mutex for list ops */
__be16 fragment_tag;
};
struct lowpan_dev_record {
struct net_device *ldev;
struct list_head list;
};
static inline struct
lowpan_dev_info *lowpan_dev_info(const struct net_device *dev)
{
return netdev_priv(dev);
}
static inline void lowpan_address_flip(u8 *src, u8 *dest)
{
int i;
for (i = 0; i < IEEE802154_ADDR_LEN; i++)
(dest)[IEEE802154_ADDR_LEN - i - 1] = (src)[i];
}
static int lowpan_header_create(struct sk_buff *skb,
struct net_device *dev,
unsigned short type, const void *_daddr,
const void *_saddr, unsigned int len)
{
const u8 *saddr = _saddr;
const u8 *daddr = _daddr;
struct ieee802154_addr_sa sa, da;
/* TODO:
* if this package isn't ipv6 one, where should it be routed?
*/
if (type != ETH_P_IPV6)
return 0;
if (!saddr)
saddr = dev->dev_addr;
raw_dump_inline(__func__, "saddr", (unsigned char *)saddr, 8);
raw_dump_inline(__func__, "daddr", (unsigned char *)daddr, 8);
lowpan_header_compress(skb, dev, type, daddr, saddr, len);
/* NOTE1: I'm still unsure about the fact that compression and WPAN
* header are created here and not later in the xmit. So wait for
* an opinion of net maintainers.
*/
/* NOTE2: to be absolutely correct, we must derive PANid information
* from MAC subif of the 'dev' and 'real_dev' network devices, but
* this isn't implemented in mainline yet, so currently we assign 0xff
*/
mac_cb(skb)->flags = IEEE802154_FC_TYPE_DATA;
mac_cb(skb)->seq = ieee802154_mlme_ops(dev)->get_dsn(dev);
/* prepare wpan address data */
sa.addr_type = IEEE802154_ADDR_LONG;
sa.pan_id = le16_to_cpu(ieee802154_mlme_ops(dev)->get_pan_id(dev));
memcpy(&(sa.hwaddr), saddr, 8);
/* intra-PAN communications */
da.pan_id = sa.pan_id;
/* if the destination address is the broadcast address, use the
* corresponding short address
*/
if (lowpan_is_addr_broadcast(daddr)) {
da.addr_type = IEEE802154_ADDR_SHORT;
da.short_addr = IEEE802154_ADDR_BROADCAST;
} else {
da.addr_type = IEEE802154_ADDR_LONG;
memcpy(&(da.hwaddr), daddr, IEEE802154_ADDR_LEN);
/* request acknowledgment */
mac_cb(skb)->flags |= MAC_CB_FLAG_ACKREQ;
}
return dev_hard_header(skb, lowpan_dev_info(dev)->real_dev,
type, (void *)&da, (void *)&sa, skb->len);
}
static int lowpan_give_skb_to_devices(struct sk_buff *skb,
struct net_device *dev)
{
struct lowpan_dev_record *entry;
struct sk_buff *skb_cp;
int stat = NET_RX_SUCCESS;
rcu_read_lock();
list_for_each_entry_rcu(entry, &lowpan_devices, list)
if (lowpan_dev_info(entry->ldev)->real_dev == skb->dev) {
skb_cp = skb_copy(skb, GFP_ATOMIC);
if (!skb_cp) {
stat = -ENOMEM;
break;
}
skb_cp->dev = entry->ldev;
stat = netif_rx(skb_cp);
}
rcu_read_unlock();
return stat;
}
static int process_data(struct sk_buff *skb)
{
u8 iphc0, iphc1;
const struct ieee802154_addr_sa *_saddr, *_daddr;
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)
goto drop;
if (lowpan_fetch_skb_u8(skb, &iphc0))
goto drop;
if (lowpan_fetch_skb_u8(skb, &iphc1))
goto drop;
_saddr = &mac_cb(skb)->sa;
_daddr = &mac_cb(skb)->da;
return lowpan_process_data(skb, skb->dev, (u8 *)_saddr->hwaddr,
_saddr->addr_type, IEEE802154_ADDR_LEN,
(u8 *)_daddr->hwaddr, _daddr->addr_type,
IEEE802154_ADDR_LEN, iphc0, iphc1,
lowpan_give_skb_to_devices);
drop:
kfree_skb(skb);
return -EINVAL;
}
static int lowpan_set_address(struct net_device *dev, void *p)
{
struct sockaddr *sa = p;
if (netif_running(dev))
return -EBUSY;
/* TODO: validate addr */
memcpy(dev->dev_addr, sa->sa_data, dev->addr_len);
return 0;
}
static int
lowpan_fragment_xmit(struct sk_buff *skb, u8 *head,
int mlen, int plen, int offset, int type)
{
struct sk_buff *frag;
int hlen;
hlen = (type == LOWPAN_DISPATCH_FRAG1) ?
LOWPAN_FRAG1_HEAD_SIZE : LOWPAN_FRAGN_HEAD_SIZE;
raw_dump_inline(__func__, "6lowpan fragment header", head, hlen);
frag = netdev_alloc_skb(skb->dev,
hlen + mlen + plen + IEEE802154_MFR_SIZE);
if (!frag)
return -ENOMEM;
frag->priority = skb->priority;
/* copy header, MFR and payload */
skb_put(frag, mlen);
skb_copy_to_linear_data(frag, skb_mac_header(skb), mlen);
skb_put(frag, hlen);
skb_copy_to_linear_data_offset(frag, mlen, head, hlen);
skb_put(frag, plen);
skb_copy_to_linear_data_offset(frag, mlen + hlen,
skb_network_header(skb) + offset, plen);
raw_dump_table(__func__, " raw fragment dump", frag->data, frag->len);
return dev_queue_xmit(frag);
}
static int
lowpan_skb_fragmentation(struct sk_buff *skb, struct net_device *dev)
{
int err;
u16 dgram_offset, dgram_size, payload_length, header_length,
lowpan_size, frag_plen, offset;
__be16 tag;
u8 head[5];
header_length = skb->mac_len;
payload_length = skb->len - header_length;
tag = lowpan_dev_info(dev)->fragment_tag++;
lowpan_size = skb_network_header_len(skb);
dgram_size = lowpan_uncompress_size(skb, &dgram_offset) -
header_length;
/* first fragment header */
head[0] = LOWPAN_DISPATCH_FRAG1 | ((dgram_size >> 8) & 0x7);
head[1] = dgram_size & 0xff;
memcpy(head + 2, &tag, sizeof(tag));
/* calc the nearest payload length(divided to 8) for first fragment
* which fits into a IEEE802154_MTU
*/
frag_plen = round_down(IEEE802154_MTU - header_length -
LOWPAN_FRAG1_HEAD_SIZE - lowpan_size -
IEEE802154_MFR_SIZE, 8);
err = lowpan_fragment_xmit(skb, head, header_length,
frag_plen + lowpan_size, 0,
LOWPAN_DISPATCH_FRAG1);
if (err) {
pr_debug("%s unable to send FRAG1 packet (tag: %d)",
__func__, tag);
goto exit;
}
offset = lowpan_size + frag_plen;
dgram_offset += frag_plen;
/* next fragment header */
head[0] &= ~LOWPAN_DISPATCH_FRAG1;
head[0] |= LOWPAN_DISPATCH_FRAGN;
frag_plen = round_down(IEEE802154_MTU - header_length -
LOWPAN_FRAGN_HEAD_SIZE - IEEE802154_MFR_SIZE, 8);
while (payload_length - offset > 0) {
int len = frag_plen;
head[4] = dgram_offset >> 3;
if (payload_length - offset < len)
len = payload_length - offset;
err = lowpan_fragment_xmit(skb, head, header_length, len,
offset, LOWPAN_DISPATCH_FRAGN);
if (err) {
pr_debug("%s unable to send a FRAGN packet. (tag: %d, offset: %d)\n",
__func__, tag, offset);
goto exit;
}
offset += len;
dgram_offset += len;
}
exit:
return err;
}
static netdev_tx_t lowpan_xmit(struct sk_buff *skb, struct net_device *dev)
{
int err = -1;
pr_debug("package xmit\n");
skb->dev = lowpan_dev_info(dev)->real_dev;
if (skb->dev == NULL) {
pr_debug("ERROR: no real wpan device found\n");
goto error;
}
/* Send directly if less than the MTU minus the 2 checksum bytes. */
if (skb->len <= IEEE802154_MTU - IEEE802154_MFR_SIZE) {
err = dev_queue_xmit(skb);
goto out;
}
pr_debug("frame is too big, fragmentation is needed\n");
err = lowpan_skb_fragmentation(skb, dev);
error:
dev_kfree_skb(skb);
out:
if (err)
pr_debug("ERROR: xmit failed\n");
return (err < 0) ? NET_XMIT_DROP : err;
}
static struct wpan_phy *lowpan_get_phy(const struct net_device *dev)
{
struct net_device *real_dev = lowpan_dev_info(dev)->real_dev;
return ieee802154_mlme_ops(real_dev)->get_phy(real_dev);
}
static __le16 lowpan_get_pan_id(const struct net_device *dev)
{
struct net_device *real_dev = lowpan_dev_info(dev)->real_dev;
return ieee802154_mlme_ops(real_dev)->get_pan_id(real_dev);
}
static __le16 lowpan_get_short_addr(const struct net_device *dev)
{
struct net_device *real_dev = lowpan_dev_info(dev)->real_dev;
return ieee802154_mlme_ops(real_dev)->get_short_addr(real_dev);
}
static u8 lowpan_get_dsn(const struct net_device *dev)
{
struct net_device *real_dev = lowpan_dev_info(dev)->real_dev;
return ieee802154_mlme_ops(real_dev)->get_dsn(real_dev);
}
static struct header_ops lowpan_header_ops = {
.create = lowpan_header_create,
};
static struct lock_class_key lowpan_tx_busylock;
static struct lock_class_key lowpan_netdev_xmit_lock_key;
static void lowpan_set_lockdep_class_one(struct net_device *dev,
struct netdev_queue *txq,
void *_unused)
{
lockdep_set_class(&txq->_xmit_lock,
&lowpan_netdev_xmit_lock_key);
}
static int lowpan_dev_init(struct net_device *dev)
{
netdev_for_each_tx_queue(dev, lowpan_set_lockdep_class_one, NULL);
dev->qdisc_tx_busylock = &lowpan_tx_busylock;
return 0;
}
static const struct net_device_ops lowpan_netdev_ops = {
.ndo_init = lowpan_dev_init,
.ndo_start_xmit = lowpan_xmit,
.ndo_set_mac_address = lowpan_set_address,
};
static struct ieee802154_mlme_ops lowpan_mlme = {
.get_pan_id = lowpan_get_pan_id,
.get_phy = lowpan_get_phy,
.get_short_addr = lowpan_get_short_addr,
.get_dsn = lowpan_get_dsn,
};
static void lowpan_setup(struct net_device *dev)
{
dev->addr_len = IEEE802154_ADDR_LEN;
memset(dev->broadcast, 0xff, IEEE802154_ADDR_LEN);
dev->type = ARPHRD_IEEE802154;
/* Frame Control + Sequence Number + Address fields + Security Header */
dev->hard_header_len = 2 + 1 + 20 + 14;
dev->needed_tailroom = 2; /* FCS */
dev->mtu = 1281;
dev->tx_queue_len = 0;
dev->flags = IFF_BROADCAST | IFF_MULTICAST;
dev->watchdog_timeo = 0;
dev->netdev_ops = &lowpan_netdev_ops;
dev->header_ops = &lowpan_header_ops;
dev->ml_priv = &lowpan_mlme;
dev->destructor = free_netdev;
}
static int lowpan_validate(struct nlattr *tb[], struct nlattr *data[])
{
if (tb[IFLA_ADDRESS]) {
if (nla_len(tb[IFLA_ADDRESS]) != IEEE802154_ADDR_LEN)
return -EINVAL;
}
return 0;
}
static int lowpan_rcv(struct sk_buff *skb, struct net_device *dev,
struct packet_type *pt, struct net_device *orig_dev)
{
struct sk_buff *local_skb;
int ret;
if (!netif_running(dev))
goto drop_skb;
if (dev->type != ARPHRD_IEEE802154)
goto drop_skb;
local_skb = skb_clone(skb, GFP_ATOMIC);
if (!local_skb)
goto drop_skb;
kfree_skb(skb);
/* check that it's our buffer */
if (skb->data[0] == LOWPAN_DISPATCH_IPV6) {
local_skb->protocol = htons(ETH_P_IPV6);
local_skb->pkt_type = PACKET_HOST;
/* Pull off the 1-byte of 6lowpan header. */
skb_pull(local_skb, 1);
ret = lowpan_give_skb_to_devices(local_skb, NULL);
if (ret == NET_RX_DROP)
goto drop;
} else {
switch (skb->data[0] & 0xe0) {
case LOWPAN_DISPATCH_IPHC: /* ipv6 datagram */
ret = process_data(local_skb);
if (ret == NET_RX_DROP)
goto drop;
break;
case LOWPAN_DISPATCH_FRAG1: /* first fragment header */
ret = lowpan_frag_rcv(local_skb, LOWPAN_DISPATCH_FRAG1);
if (ret == 1) {
ret = process_data(local_skb);
if (ret == NET_RX_DROP)
goto drop;
}
break;
case LOWPAN_DISPATCH_FRAGN: /* next fragments headers */
ret = lowpan_frag_rcv(local_skb, LOWPAN_DISPATCH_FRAGN);
if (ret == 1) {
ret = process_data(local_skb);
if (ret == NET_RX_DROP)
goto drop;
}
break;
default:
break;
}
}
return NET_RX_SUCCESS;
drop_skb:
kfree_skb(skb);
drop:
return NET_RX_DROP;
}
static int lowpan_newlink(struct net *src_net, struct net_device *dev,
struct nlattr *tb[], struct nlattr *data[])
{
struct net_device *real_dev;
struct lowpan_dev_record *entry;
pr_debug("adding new link\n");
if (!tb[IFLA_LINK])
return -EINVAL;
/* find and hold real wpan device */
real_dev = dev_get_by_index(src_net, nla_get_u32(tb[IFLA_LINK]));
if (!real_dev)
return -ENODEV;
if (real_dev->type != ARPHRD_IEEE802154) {
dev_put(real_dev);
return -EINVAL;
}
lowpan_dev_info(dev)->real_dev = real_dev;
mutex_init(&lowpan_dev_info(dev)->dev_list_mtx);
entry = kzalloc(sizeof(*entry), GFP_KERNEL);
if (!entry) {
dev_put(real_dev);
lowpan_dev_info(dev)->real_dev = NULL;
return -ENOMEM;
}
entry->ldev = dev;
/* Set the lowpan harware address to the wpan hardware address. */
memcpy(dev->dev_addr, real_dev->dev_addr, IEEE802154_ADDR_LEN);
mutex_lock(&lowpan_dev_info(dev)->dev_list_mtx);
INIT_LIST_HEAD(&entry->list);
list_add_tail(&entry->list, &lowpan_devices);
mutex_unlock(&lowpan_dev_info(dev)->dev_list_mtx);
register_netdevice(dev);
return 0;
}
static void lowpan_dellink(struct net_device *dev, struct list_head *head)
{
struct lowpan_dev_info *lowpan_dev = lowpan_dev_info(dev);
struct net_device *real_dev = lowpan_dev->real_dev;
struct lowpan_dev_record *entry, *tmp;
ASSERT_RTNL();
mutex_lock(&lowpan_dev_info(dev)->dev_list_mtx);
list_for_each_entry_safe(entry, tmp, &lowpan_devices, list) {
if (entry->ldev == dev) {
list_del(&entry->list);
kfree(entry);
}
}
mutex_unlock(&lowpan_dev_info(dev)->dev_list_mtx);
mutex_destroy(&lowpan_dev_info(dev)->dev_list_mtx);
unregister_netdevice_queue(dev, head);
dev_put(real_dev);
}
static struct rtnl_link_ops lowpan_link_ops __read_mostly = {
.kind = "lowpan",
.priv_size = sizeof(struct lowpan_dev_info),
.setup = lowpan_setup,
.newlink = lowpan_newlink,
.dellink = lowpan_dellink,
.validate = lowpan_validate,
};
static inline int __init lowpan_netlink_init(void)
{
return rtnl_link_register(&lowpan_link_ops);
}
static inline void lowpan_netlink_fini(void)
{
rtnl_link_unregister(&lowpan_link_ops);
}
static int lowpan_device_event(struct notifier_block *unused,
unsigned long event, void *ptr)
{
struct net_device *dev = netdev_notifier_info_to_dev(ptr);
LIST_HEAD(del_list);
struct lowpan_dev_record *entry, *tmp;
if (dev->type != ARPHRD_IEEE802154)
goto out;
if (event == NETDEV_UNREGISTER) {
list_for_each_entry_safe(entry, tmp, &lowpan_devices, list) {
if (lowpan_dev_info(entry->ldev)->real_dev == dev)
lowpan_dellink(entry->ldev, &del_list);
}
unregister_netdevice_many(&del_list);
}
out:
return NOTIFY_DONE;
}
static struct notifier_block lowpan_dev_notifier = {
.notifier_call = lowpan_device_event,
};
static struct packet_type lowpan_packet_type = {
.type = htons(ETH_P_IEEE802154),
.func = lowpan_rcv,
};
static int __init lowpan_init_module(void)
{
int err = 0;
err = lowpan_net_frag_init();
if (err < 0)
goto out;
err = lowpan_netlink_init();
if (err < 0)
goto out_frag;
dev_add_pack(&lowpan_packet_type);
err = register_netdevice_notifier(&lowpan_dev_notifier);
if (err < 0)
goto out_pack;
return 0;
out_pack:
dev_remove_pack(&lowpan_packet_type);
lowpan_netlink_fini();
out_frag:
lowpan_net_frag_exit();
out:
return err;
}
static void __exit lowpan_cleanup_module(void)
{
lowpan_netlink_fini();
dev_remove_pack(&lowpan_packet_type);
lowpan_net_frag_exit();
unregister_netdevice_notifier(&lowpan_dev_notifier);
}
module_init(lowpan_init_module);
module_exit(lowpan_cleanup_module);
MODULE_LICENSE("GPL");
MODULE_ALIAS_RTNL_LINK("lowpan");