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6lowpan: handling 6lowpan fragmentation via inet_frag api

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This patch drops the current way of 6lowpan fragmentation on receiving
side and replace it with a implementation which use the inet_frag api.
The old fragmentation handling has some race conditions and isn't
rfc4944 compatible. Also adding support to match fragments on
destination address, source address, tag value and datagram_size
which is missing in the current implementation.

Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Alexander Aring 2014-02-28 07:32:50 +01:00 committed by David S. Miller
parent 633fc86ff6
commit 7240cdec60
5 changed files with 690 additions and 209 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

9
include/net/netns/ieee802154_6lowpan.h
View file

@ -7,7 +7,16 @@
#ifndef __NETNS_IEEE802154_6LOWPAN_H__
#define __NETNS_IEEE802154_6LOWPAN_H__
struct netns_sysctl_lowpan {
#ifdef CONFIG_SYSCTL
struct ctl_table_header *frags_hdr;
#endif
};
struct netns_ieee802154_lowpan {
struct netns_sysctl_lowpan sysctl;
struct netns_frags frags;
u16 max_dsize;
};
#endif

258
net/ieee802154/6lowpan_rtnl.c
View file

@ -54,6 +54,7 @@
#include <net/ieee802154_netdev.h>
#include <net/ipv6.h>
#include "reassembly.h"
#include "6lowpan.h"
static LIST_HEAD(lowpan_devices);
@ -70,18 +71,6 @@ struct lowpan_dev_record {
struct list_head list;
};
struct lowpan_fragment {
struct sk_buff *skb; /* skb to be assembled */
u16 length; /* length to be assemled */
u32 bytes_rcv; /* bytes received */
u16 tag; /* current fragment tag */
struct timer_list timer; /* assembling timer */
struct list_head list; /* fragments list */
};
static LIST_HEAD(lowpan_fragments);
static DEFINE_SPINLOCK(flist_lock);
static inline struct
lowpan_dev_info *lowpan_dev_info(const struct net_device *dev)
{
@ -179,69 +168,6 @@ static int lowpan_give_skb_to_devices(struct sk_buff *skb,
return stat;
}
static void lowpan_fragment_timer_expired(unsigned long entry_addr)
{
struct lowpan_fragment *entry = (struct lowpan_fragment *)entry_addr;
pr_debug("timer expired for frame with tag %d\n", entry->tag);
list_del(&entry->list);
dev_kfree_skb(entry->skb);
kfree(entry);
}
static struct lowpan_fragment *
lowpan_alloc_new_frame(struct sk_buff *skb, u16 len, u16 tag)
{
struct lowpan_fragment *frame;
frame = kzalloc(sizeof(struct lowpan_fragment),
GFP_ATOMIC);
if (!frame)
goto frame_err;
INIT_LIST_HEAD(&frame->list);
frame->length = len;
frame->tag = tag;
/* allocate buffer for frame assembling */
frame->skb = netdev_alloc_skb_ip_align(skb->dev, frame->length +
sizeof(struct ipv6hdr));
if (!frame->skb)
goto skb_err;
frame->skb->priority = skb->priority;
/* reserve headroom for uncompressed ipv6 header */
skb_reserve(frame->skb, sizeof(struct ipv6hdr));
skb_put(frame->skb, frame->length);
/* copy the first control block to keep a
* trace of the link-layer addresses in case
* of a link-local compressed address
*/
memcpy(frame->skb->cb, skb->cb, sizeof(skb->cb));
init_timer(&frame->timer);
/* time out is the same as for ipv6 - 60 sec */
frame->timer.expires = jiffies + LOWPAN_FRAG_TIMEOUT;
frame->timer.data = (unsigned long)frame;
frame->timer.function = lowpan_fragment_timer_expired;
add_timer(&frame->timer);
list_add_tail(&frame->list, &lowpan_fragments);
return frame;
skb_err:
kfree(frame);
frame_err:
return NULL;
}
static int process_data(struct sk_buff *skb)
{
u8 iphc0, iphc1;
@ -255,94 +181,6 @@ static int process_data(struct sk_buff *skb)
if (lowpan_fetch_skb_u8(skb, &iphc0))
goto drop;
/* fragments assembling */
switch (iphc0 & LOWPAN_DISPATCH_MASK) {
case LOWPAN_DISPATCH_FRAG1:
case LOWPAN_DISPATCH_FRAGN:
{
struct lowpan_fragment *frame;
/* slen stores the rightmost 8 bits of the 11 bits length */
u8 slen, offset = 0;
u16 len, tag;
bool found = false;
if (lowpan_fetch_skb_u8(skb, &slen) || /* frame length */
lowpan_fetch_skb_u16(skb, &tag)) /* fragment tag */
goto drop;
/* adds the 3 MSB to the 8 LSB to retrieve the 11 bits length */
len = ((iphc0 & 7) << 8) | slen;
if ((iphc0 & LOWPAN_DISPATCH_MASK) == LOWPAN_DISPATCH_FRAG1) {
pr_debug("%s received a FRAG1 packet (tag: %d, "
"size of the entire IP packet: %d)",
__func__, tag, len);
} else { /* FRAGN */
if (lowpan_fetch_skb_u8(skb, &offset))
goto unlock_and_drop;
pr_debug("%s received a FRAGN packet (tag: %d, "
"size of the entire IP packet: %d, "
"offset: %d)", __func__, tag, len, offset * 8);
}
/*
* check if frame assembling with the same tag is
* already in progress
*/
spin_lock_bh(&flist_lock);
list_for_each_entry(frame, &lowpan_fragments, list)
if (frame->tag == tag) {
found = true;
break;
}
/* alloc new frame structure */
if (!found) {
pr_debug("%s first fragment received for tag %d, "
"begin packet reassembly", __func__, tag);
frame = lowpan_alloc_new_frame(skb, len, tag);
if (!frame)
goto unlock_and_drop;
}
/* if payload fits buffer, copy it */
if (likely((offset * 8 + skb->len) <= frame->length))
skb_copy_to_linear_data_offset(frame->skb, offset * 8,
skb->data, skb->len);
else
goto unlock_and_drop;
frame->bytes_rcv += skb->len;
/* frame assembling complete */
if ((frame->bytes_rcv == frame->length) &&
frame->timer.expires > jiffies) {
/* if timer haven't expired - first of all delete it */
del_timer_sync(&frame->timer);
list_del(&frame->list);
spin_unlock_bh(&flist_lock);
pr_debug("%s successfully reassembled fragment "
"(tag %d)", __func__, tag);
dev_kfree_skb(skb);
skb = frame->skb;
kfree(frame);
if (lowpan_fetch_skb_u8(skb, &iphc0))
goto drop;
break;
}
spin_unlock_bh(&flist_lock);
return kfree_skb(skb), 0;
}
default:
break;
}
if (lowpan_fetch_skb_u8(skb, &iphc1))
goto drop;
@ -355,8 +193,6 @@ static int process_data(struct sk_buff *skb)
IEEE802154_ADDR_LEN, iphc0, iphc1,
lowpan_give_skb_to_devices);
unlock_and_drop:
spin_unlock_bh(&flist_lock);
drop:
kfree_skb(skb);
return -EINVAL;
@ -603,44 +439,53 @@ 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;
goto drop_skb;
if (dev->type != ARPHRD_IEEE802154)
goto drop;
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) {
/* Copy the packet so that the IPv6 header is
* properly aligned.
*/
local_skb = skb_copy_expand(skb, NET_SKB_PAD - 1,
skb_tailroom(skb), GFP_ATOMIC);
if (!local_skb)
goto drop;
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);
lowpan_give_skb_to_devices(local_skb, NULL);
kfree_skb(local_skb);
kfree_skb(skb);
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 */
case LOWPAN_DISPATCH_FRAG1: /* first fragment header */
case LOWPAN_DISPATCH_FRAGN: /* next fragments headers */
local_skb = skb_clone(skb, GFP_ATOMIC);
if (!local_skb)
ret = process_data(local_skb);
if (ret == NET_RX_DROP)
goto drop;
process_data(local_skb);
kfree_skb(skb);
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;
@ -648,9 +493,9 @@ static int lowpan_rcv(struct sk_buff *skb, struct net_device *dev,
}
return NET_RX_SUCCESS;
drop:
drop_skb:
kfree_skb(skb);
drop:
return NET_RX_DROP;
}
@ -778,43 +623,40 @@ static int __init lowpan_init_module(void)
{
int err = 0;
err = lowpan_netlink_init();
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) {
dev_remove_pack(&lowpan_packet_type);
lowpan_netlink_fini();
}
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)
{
struct lowpan_fragment *frame, *tframe;
lowpan_netlink_fini();
dev_remove_pack(&lowpan_packet_type);
unregister_netdevice_notifier(&lowpan_dev_notifier);
lowpan_net_frag_exit();
/* Now 6lowpan packet_type is removed, so no new fragments are
* expected on RX, therefore that's the time to clean incomplete
* fragments.
*/
spin_lock_bh(&flist_lock);
list_for_each_entry_safe(frame, tframe, &lowpan_fragments, list) {
del_timer_sync(&frame->timer);
list_del(&frame->list);
dev_kfree_skb(frame->skb);
kfree(frame);
}
spin_unlock_bh(&flist_lock);
unregister_netdevice_notifier(&lowpan_dev_notifier);
}
module_init(lowpan_init_module);

2
net/ieee802154/Makefile
View file

@ -2,6 +2,6 @@ obj-$(CONFIG_IEEE802154) += ieee802154.o af_802154.o
obj-$(CONFIG_IEEE802154_6LOWPAN) += 6lowpan.o
obj-$(CONFIG_6LOWPAN_IPHC) += 6lowpan_iphc.o
6lowpan-y := 6lowpan_rtnl.o
6lowpan-y := 6lowpan_rtnl.o reassembly.o
ieee802154-y := netlink.o nl-mac.o nl-phy.o nl_policy.o wpan-class.o
af_802154-y := af_ieee802154.o raw.o dgram.o

564
net/ieee802154/reassembly.c Normal file
View file

@ -0,0 +1,564 @@
/* 6LoWPAN fragment reassembly
*
*
* Authors:
* Alexander Aring <aar@pengutronix.de>
*
* Based on: net/ipv6/reassembly.c
*
* This program 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
* 2 of the License, or (at your option) any later version.
*/
#define pr_fmt(fmt) "6LoWPAN: " fmt
#include <linux/net.h>
#include <linux/list.h>
#include <linux/netdevice.h>
#include <linux/random.h>
#include <linux/jhash.h>
#include <linux/skbuff.h>
#include <linux/slab.h>
#include <linux/export.h>
#include <net/ieee802154_netdev.h>
#include <net/ipv6.h>
#include <net/inet_frag.h>
#include "6lowpan.h"
#include "reassembly.h"
static struct inet_frags lowpan_frags;
static int lowpan_frag_reasm(struct lowpan_frag_queue *fq,
struct sk_buff *prev, struct net_device *dev);
static unsigned int lowpan_hash_frag(__be16 tag, __be16 d_size,
const struct ieee802154_addr *saddr,
const struct ieee802154_addr *daddr)
{
u32 c;
net_get_random_once(&lowpan_frags.rnd, sizeof(lowpan_frags.rnd));
c = jhash_3words(ieee802154_addr_hash(saddr),
ieee802154_addr_hash(daddr),
(__force u32)(tag + (d_size << 16)),
lowpan_frags.rnd);
return c & (INETFRAGS_HASHSZ - 1);
}
static unsigned int lowpan_hashfn(struct inet_frag_queue *q)
{
struct lowpan_frag_queue *fq;
fq = container_of(q, struct lowpan_frag_queue, q);
return lowpan_hash_frag(fq->tag, fq->d_size, &fq->saddr, &fq->daddr);
}
bool lowpan_frag_match(struct inet_frag_queue *q, void *a)
{
struct lowpan_frag_queue *fq;
struct lowpan_create_arg *arg = a;
fq = container_of(q, struct lowpan_frag_queue, q);
return fq->tag == arg->tag && fq->d_size == arg->d_size &&
ieee802154_addr_addr_equal(&fq->saddr, arg->src) &&
ieee802154_addr_addr_equal(&fq->daddr, arg->dst);
}
EXPORT_SYMBOL(lowpan_frag_match);
void lowpan_frag_init(struct inet_frag_queue *q, void *a)
{
struct lowpan_frag_queue *fq;
struct lowpan_create_arg *arg = a;
fq = container_of(q, struct lowpan_frag_queue, q);
fq->tag = arg->tag;
fq->d_size = arg->d_size;
fq->saddr = *arg->src;
fq->daddr = *arg->dst;
}
EXPORT_SYMBOL(lowpan_frag_init);
void lowpan_expire_frag_queue(struct frag_queue *fq, struct inet_frags *frags)
{
spin_lock(&fq->q.lock);
if (fq->q.last_in & INET_FRAG_COMPLETE)
goto out;
inet_frag_kill(&fq->q, frags);
out:
spin_unlock(&fq->q.lock);
inet_frag_put(&fq->q, frags);
}
EXPORT_SYMBOL(lowpan_expire_frag_queue);
static void lowpan_frag_expire(unsigned long data)
{
struct frag_queue *fq;
struct net *net;
fq = container_of((struct inet_frag_queue *)data, struct frag_queue, q);
net = container_of(fq->q.net, struct net, ieee802154_lowpan.frags);
lowpan_expire_frag_queue(fq, &lowpan_frags);
}
static inline struct lowpan_frag_queue *
fq_find(struct net *net, const struct ieee802154_frag_info *frag_info,
const struct ieee802154_addr *src, const struct ieee802154_addr *dst)
{
struct inet_frag_queue *q;
struct lowpan_create_arg arg;
unsigned int hash;
arg.tag = frag_info->d_tag;
arg.d_size = frag_info->d_size;
arg.src = src;
arg.dst = dst;
read_lock(&lowpan_frags.lock);
hash = lowpan_hash_frag(frag_info->d_tag, frag_info->d_size, src, dst);
q = inet_frag_find(&net->ieee802154_lowpan.frags,
&lowpan_frags, &arg, hash);
if (IS_ERR_OR_NULL(q)) {
inet_frag_maybe_warn_overflow(q, pr_fmt());
return NULL;
}
return container_of(q, struct lowpan_frag_queue, q);
}
static int lowpan_frag_queue(struct lowpan_frag_queue *fq,
struct sk_buff *skb, const u8 frag_type)
{
struct sk_buff *prev, *next;
struct net_device *dev;
int end, offset;
if (fq->q.last_in & INET_FRAG_COMPLETE)
goto err;
offset = mac_cb(skb)->frag_info.d_offset << 3;
end = mac_cb(skb)->frag_info.d_size;
/* Is this the final fragment? */
if (offset + skb->len == end) {
/* If we already have some bits beyond end
* or have different end, the segment is corrupted.
*/
if (end < fq->q.len ||
((fq->q.last_in & INET_FRAG_LAST_IN) && end != fq->q.len))
goto err;
fq->q.last_in |= INET_FRAG_LAST_IN;
fq->q.len = end;
} else {
if (end > fq->q.len) {
/* Some bits beyond end -> corruption. */
if (fq->q.last_in & INET_FRAG_LAST_IN)
goto err;
fq->q.len = end;
}
}
/* Find out which fragments are in front and at the back of us
* in the chain of fragments so far. We must know where to put
* this fragment, right?
*/
prev = fq->q.fragments_tail;
if (!prev || mac_cb(prev)->frag_info.d_offset <
mac_cb(skb)->frag_info.d_offset) {
next = NULL;
goto found;
}
prev = NULL;
for (next = fq->q.fragments; next != NULL; next = next->next) {
if (mac_cb(next)->frag_info.d_offset >=
mac_cb(skb)->frag_info.d_offset)
break; /* bingo! */
prev = next;
}
found:
/* Insert this fragment in the chain of fragments. */
skb->next = next;
if (!next)
fq->q.fragments_tail = skb;
if (prev)
prev->next = skb;
else
fq->q.fragments = skb;
dev = skb->dev;
if (dev)
skb->dev = NULL;
fq->q.stamp = skb->tstamp;
if (frag_type == LOWPAN_DISPATCH_FRAG1) {
/* Calculate uncomp. 6lowpan header to estimate full size */
fq->q.meat += lowpan_uncompress_size(skb, NULL);
fq->q.last_in |= INET_FRAG_FIRST_IN;
} else {
fq->q.meat += skb->len;
}
add_frag_mem_limit(&fq->q, skb->truesize);
if (fq->q.last_in == (INET_FRAG_FIRST_IN | INET_FRAG_LAST_IN) &&
fq->q.meat == fq->q.len) {
int res;
unsigned long orefdst = skb->_skb_refdst;
skb->_skb_refdst = 0UL;
res = lowpan_frag_reasm(fq, prev, dev);
skb->_skb_refdst = orefdst;
return res;
}
inet_frag_lru_move(&fq->q);
return -1;
err:
kfree_skb(skb);
return -1;
}
/* Check if this packet is complete.
* Returns NULL on failure by any reason, and pointer
* to current nexthdr field in reassembled frame.
*
* It is called with locked fq, and caller must check that
* queue is eligible for reassembly i.e. it is not COMPLETE,
* the last and the first frames arrived and all the bits are here.
*/
static int lowpan_frag_reasm(struct lowpan_frag_queue *fq, struct sk_buff *prev,
struct net_device *dev)
{
struct sk_buff *fp, *head = fq->q.fragments;
int sum_truesize;
inet_frag_kill(&fq->q, &lowpan_frags);
/* Make the one we just received the head. */
if (prev) {
head = prev->next;
fp = skb_clone(head, GFP_ATOMIC);
if (!fp)
goto out_oom;
fp->next = head->next;
if (!fp->next)
fq->q.fragments_tail = fp;
prev->next = fp;
skb_morph(head, fq->q.fragments);
head->next = fq->q.fragments->next;
consume_skb(fq->q.fragments);
fq->q.fragments = head;
}
/* Head of list must not be cloned. */
if (skb_unclone(head, GFP_ATOMIC))
goto out_oom;
/* If the first fragment is fragmented itself, we split
* it to two chunks: the first with data and paged part
* and the second, holding only fragments.
*/
if (skb_has_frag_list(head)) {
struct sk_buff *clone;
int i, plen = 0;
clone = alloc_skb(0, GFP_ATOMIC);
if (!clone)
goto out_oom;
clone->next = head->next;
head->next = clone;
skb_shinfo(clone)->frag_list = skb_shinfo(head)->frag_list;
skb_frag_list_init(head);
for (i = 0; i < skb_shinfo(head)->nr_frags; i++)
plen += skb_frag_size(&skb_shinfo(head)->frags[i]);
clone->len = head->data_len - plen;
clone->data_len = clone->len;
head->data_len -= clone->len;
head->len -= clone->len;
add_frag_mem_limit(&fq->q, clone->truesize);
}
WARN_ON(head == NULL);
sum_truesize = head->truesize;
for (fp = head->next; fp;) {
bool headstolen;
int delta;
struct sk_buff *next = fp->next;
sum_truesize += fp->truesize;
if (skb_try_coalesce(head, fp, &headstolen, &delta)) {
kfree_skb_partial(fp, headstolen);
} else {
if (!skb_shinfo(head)->frag_list)
skb_shinfo(head)->frag_list = fp;
head->data_len += fp->len;
head->len += fp->len;
head->truesize += fp->truesize;
}
fp = next;
}
sub_frag_mem_limit(&fq->q, sum_truesize);
head->next = NULL;
head->dev = dev;
head->tstamp = fq->q.stamp;
fq->q.fragments = NULL;
fq->q.fragments_tail = NULL;
return 1;
out_oom:
net_dbg_ratelimited("lowpan_frag_reasm: no memory for reassembly\n");
return -1;
}
static int lowpan_get_frag_info(struct sk_buff *skb, const u8 frag_type,
struct ieee802154_frag_info *frag_info)
{
bool fail;
u8 pattern = 0, low = 0;
fail = lowpan_fetch_skb(skb, &pattern, 1);
fail |= lowpan_fetch_skb(skb, &low, 1);
frag_info->d_size = (pattern & 7) << 8 | low;
fail |= lowpan_fetch_skb(skb, &frag_info->d_tag, 2);
if (frag_type == LOWPAN_DISPATCH_FRAGN) {
fail |= lowpan_fetch_skb(skb, &frag_info->d_offset, 1);
} else {
skb_reset_network_header(skb);
frag_info->d_offset = 0;
}
if (unlikely(fail))
return -EIO;
return 0;
}
int lowpan_frag_rcv(struct sk_buff *skb, const u8 frag_type)
{
struct lowpan_frag_queue *fq;
struct net *net = dev_net(skb->dev);
struct ieee802154_frag_info *frag_info = &mac_cb(skb)->frag_info;
int err;
err = lowpan_get_frag_info(skb, frag_type, frag_info);
if (err < 0)
goto err;
if (frag_info->d_size > net->ieee802154_lowpan.max_dsize)
goto err;
inet_frag_evictor(&net->ieee802154_lowpan.frags, &lowpan_frags, false);
fq = fq_find(net, frag_info, &mac_cb(skb)->sa, &mac_cb(skb)->da);
if (fq != NULL) {
int ret;
spin_lock(&fq->q.lock);
ret = lowpan_frag_queue(fq, skb, frag_type);
spin_unlock(&fq->q.lock);
inet_frag_put(&fq->q, &lowpan_frags);
return ret;
}
err:
kfree_skb(skb);
return -1;
}
EXPORT_SYMBOL(lowpan_frag_rcv);
#ifdef CONFIG_SYSCTL
static struct ctl_table lowpan_frags_ns_ctl_table[] = {
{
.procname = "6lowpanfrag_high_thresh",
.data = &init_net.ieee802154_lowpan.frags.high_thresh,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
{
.procname = "6lowpanfrag_low_thresh",
.data = &init_net.ieee802154_lowpan.frags.low_thresh,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
{
.procname = "6lowpanfrag_time",
.data = &init_net.ieee802154_lowpan.frags.timeout,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec_jiffies,
},
{
.procname = "6lowpanfrag_max_datagram_size",
.data = &init_net.ieee802154_lowpan.max_dsize,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
{ }
};
static struct ctl_table lowpan_frags_ctl_table[] = {
{
.procname = "6lowpanfrag_secret_interval",
.data = &lowpan_frags.secret_interval,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec_jiffies,
},
{ }
};
static int __net_init lowpan_frags_ns_sysctl_register(struct net *net)
{
struct ctl_table *table;
struct ctl_table_header *hdr;
table = lowpan_frags_ns_ctl_table;
if (!net_eq(net, &init_net)) {
table = kmemdup(table, sizeof(lowpan_frags_ns_ctl_table),
GFP_KERNEL);
if (table == NULL)
goto err_alloc;
table[0].data = &net->ieee802154_lowpan.frags.high_thresh;
table[1].data = &net->ieee802154_lowpan.frags.low_thresh;
table[2].data = &net->ieee802154_lowpan.frags.timeout;
table[2].data = &net->ieee802154_lowpan.max_dsize;
/* Don't export sysctls to unprivileged users */
if (net->user_ns != &init_user_ns)
table[0].procname = NULL;
}
hdr = register_net_sysctl(net, "net/ieee802154/6lowpan", table);
if (hdr == NULL)
goto err_reg;
net->ieee802154_lowpan.sysctl.frags_hdr = hdr;
return 0;
err_reg:
if (!net_eq(net, &init_net))
kfree(table);
err_alloc:
return -ENOMEM;
}
static void __net_exit lowpan_frags_ns_sysctl_unregister(struct net *net)
{
struct ctl_table *table;
table = net->ieee802154_lowpan.sysctl.frags_hdr->ctl_table_arg;
unregister_net_sysctl_table(net->ieee802154_lowpan.sysctl.frags_hdr);
if (!net_eq(net, &init_net))
kfree(table);
}
static struct ctl_table_header *lowpan_ctl_header;
static int lowpan_frags_sysctl_register(void)
{
lowpan_ctl_header = register_net_sysctl(&init_net,
"net/ieee802154/6lowpan",
lowpan_frags_ctl_table);
return lowpan_ctl_header == NULL ? -ENOMEM : 0;
}
static void lowpan_frags_sysctl_unregister(void)
{
unregister_net_sysctl_table(lowpan_ctl_header);
}
#else
static inline int lowpan_frags_ns_sysctl_register(struct net *net)
{
return 0;
}
static inline void lowpan_frags_ns_sysctl_unregister(struct net *net)
{
}
static inline int lowpan_frags_sysctl_register(void)
{
return 0;
}
static inline void lowpan_frags_sysctl_unregister(void)
{
}
#endif
static int __net_init lowpan_frags_init_net(struct net *net)
{
net->ieee802154_lowpan.frags.high_thresh = IPV6_FRAG_HIGH_THRESH;
net->ieee802154_lowpan.frags.low_thresh = IPV6_FRAG_LOW_THRESH;
net->ieee802154_lowpan.frags.timeout = IPV6_FRAG_TIMEOUT;
net->ieee802154_lowpan.max_dsize = 0xFFFF;
inet_frags_init_net(&net->ieee802154_lowpan.frags);
return lowpan_frags_ns_sysctl_register(net);
}
static void __net_exit lowpan_frags_exit_net(struct net *net)
{
lowpan_frags_ns_sysctl_unregister(net);
inet_frags_exit_net(&net->ieee802154_lowpan.frags, &lowpan_frags);
}
static struct pernet_operations lowpan_frags_ops = {
.init = lowpan_frags_init_net,
.exit = lowpan_frags_exit_net,
};
int __init lowpan_net_frag_init(void)
{
int ret;
ret = lowpan_frags_sysctl_register();
if (ret)
goto out;
ret = register_pernet_subsys(&lowpan_frags_ops);
if (ret)
goto err_pernet;
lowpan_frags.hashfn = lowpan_hashfn;
lowpan_frags.constructor = lowpan_frag_init;
lowpan_frags.destructor = NULL;
lowpan_frags.skb_free = NULL;
lowpan_frags.qsize = sizeof(struct frag_queue);
lowpan_frags.match = lowpan_frag_match;
lowpan_frags.frag_expire = lowpan_frag_expire;
lowpan_frags.secret_interval = 10 * 60 * HZ;
inet_frags_init(&lowpan_frags);
err_pernet:
lowpan_frags_sysctl_unregister();
out:
return ret;
}
void lowpan_net_frag_exit(void)
{
inet_frags_fini(&lowpan_frags);
lowpan_frags_sysctl_unregister();
unregister_pernet_subsys(&lowpan_frags_ops);
}

66
net/ieee802154/reassembly.h Normal file
View file

@ -0,0 +1,66 @@
#ifndef __IEEE802154_6LOWPAN_REASSEMBLY_H__
#define __IEEE802154_6LOWPAN_REASSEMBLY_H__
#include <net/inet_frag.h>
struct lowpan_create_arg {
__be16 tag;
u16 d_size;
const struct ieee802154_addr *src;
const struct ieee802154_addr *dst;
};
/* Equivalent of ipv4 struct ip
*/
struct lowpan_frag_queue {
struct inet_frag_queue q;
__be16 tag;
u16 d_size;
struct ieee802154_addr saddr;
struct ieee802154_addr daddr;
};
static inline u32 ieee802154_addr_hash(const struct ieee802154_addr *a)
{
switch (a->addr_type) {
case IEEE802154_ADDR_LONG:
return (__force u32)((((u32 *)a->hwaddr))[0] ^
((u32 *)(a->hwaddr))[1]);
case IEEE802154_ADDR_SHORT:
return (__force u32)(a->short_addr);
default:
return 0;
}
}
static inline bool ieee802154_addr_addr_equal(const struct ieee802154_addr *a1,
const struct ieee802154_addr *a2)
{
if (a1->pan_id != a2->pan_id)
return false;
if (a1->addr_type != a2->addr_type)
return false;
switch (a1->addr_type) {
case IEEE802154_ADDR_LONG:
if (memcmp(a1->hwaddr, a2->hwaddr, IEEE802154_ADDR_LEN))
return false;
break;
case IEEE802154_ADDR_SHORT:
if (a1->short_addr != a2->short_addr)
return false;
break;
default:
return false;
}
return true;
}
int lowpan_frag_rcv(struct sk_buff *skb, const u8 frag_type);
void lowpan_net_frag_exit(void);
int lowpan_net_frag_init(void);
#endif /* __IEEE802154_6LOWPAN_REASSEMBLY_H__ */