reassembly.c revision ac18e7509e7df327e30d6e073a787d922eaf211d 
1/*
2 *	IPv6 fragment reassembly
3 *	Linux INET6 implementation
4 *
5 *	Authors:
6 *	Pedro Roque		<roque@di.fc.ul.pt>
7 *
8 *	$Id: reassembly.c,v 1.26 2001/03/07 22:00:57 davem Exp $
9 *
10 *	Based on: net/ipv4/ip_fragment.c
11 *
12 *	This program is free software; you can redistribute it and/or
13 *      modify it under the terms of the GNU General Public License
14 *      as published by the Free Software Foundation; either version
15 *      2 of the License, or (at your option) any later version.
16 */
17
18/*
19 *	Fixes:
20 *	Andi Kleen	Make it work with multiple hosts.
21 *			More RFC compliance.
22 *
23 *      Horst von Brand Add missing #include <linux/string.h>
24 *	Alexey Kuznetsov	SMP races, threading, cleanup.
25 *	Patrick McHardy		LRU queue of frag heads for evictor.
26 *	Mitsuru KANDA @USAGI	Register inet6_protocol{}.
27 *	David Stevens and
28 *	YOSHIFUJI,H. @USAGI	Always remove fragment header to
29 *				calculate ICV correctly.
30 */
31#include <linux/errno.h>
32#include <linux/types.h>
33#include <linux/string.h>
34#include <linux/socket.h>
35#include <linux/sockios.h>
36#include <linux/jiffies.h>
37#include <linux/net.h>
38#include <linux/list.h>
39#include <linux/netdevice.h>
40#include <linux/in6.h>
41#include <linux/ipv6.h>
42#include <linux/icmpv6.h>
43#include <linux/random.h>
44#include <linux/jhash.h>
45#include <linux/skbuff.h>
46
47#include <net/sock.h>
48#include <net/snmp.h>
49
50#include <net/ipv6.h>
51#include <net/ip6_route.h>
52#include <net/protocol.h>
53#include <net/transp_v6.h>
54#include <net/rawv6.h>
55#include <net/ndisc.h>
56#include <net/addrconf.h>
57#include <net/inet_frag.h>
58
59struct ip6frag_skb_cb
60{
61	struct inet6_skb_parm	h;
62	int			offset;
63};
64
65#define FRAG6_CB(skb)	((struct ip6frag_skb_cb*)((skb)->cb))
66
67
68/*
69 *	Equivalent of ipv4 struct ipq
70 */
71
72struct frag_queue
73{
74	struct inet_frag_queue	q;
75
76	__be32			id;		/* fragment id		*/
77	struct in6_addr		saddr;
78	struct in6_addr		daddr;
79
80	int			iif;
81	unsigned int		csum;
82	__u16			nhoffset;
83};
84
85static struct inet_frags ip6_frags;
86
87int ip6_frag_nqueues(void)
88{
89	return ip6_frags.nqueues;
90}
91
92int ip6_frag_mem(void)
93{
94	return atomic_read(&ip6_frags.mem);
95}
96
97static int ip6_frag_reasm(struct frag_queue *fq, struct sk_buff *prev,
98			  struct net_device *dev);
99
100/*
101 * callers should be careful not to use the hash value outside the ipfrag_lock
102 * as doing so could race with ipfrag_hash_rnd being recalculated.
103 */
104static unsigned int ip6qhashfn(__be32 id, struct in6_addr *saddr,
105			       struct in6_addr *daddr)
106{
107	u32 a, b, c;
108
109	a = (__force u32)saddr->s6_addr32[0];
110	b = (__force u32)saddr->s6_addr32[1];
111	c = (__force u32)saddr->s6_addr32[2];
112
113	a += JHASH_GOLDEN_RATIO;
114	b += JHASH_GOLDEN_RATIO;
115	c += ip6_frags.rnd;
116	__jhash_mix(a, b, c);
117
118	a += (__force u32)saddr->s6_addr32[3];
119	b += (__force u32)daddr->s6_addr32[0];
120	c += (__force u32)daddr->s6_addr32[1];
121	__jhash_mix(a, b, c);
122
123	a += (__force u32)daddr->s6_addr32[2];
124	b += (__force u32)daddr->s6_addr32[3];
125	c += (__force u32)id;
126	__jhash_mix(a, b, c);
127
128	return c & (INETFRAGS_HASHSZ - 1);
129}
130
131static unsigned int ip6_hashfn(struct inet_frag_queue *q)
132{
133	struct frag_queue *fq;
134
135	fq = container_of(q, struct frag_queue, q);
136	return ip6qhashfn(fq->id, &fq->saddr, &fq->daddr);
137}
138
139int ip6_frag_match(struct inet_frag_queue *q, void *a)
140{
141	struct frag_queue *fq;
142	struct ip6_create_arg *arg = a;
143
144	fq = container_of(q, struct frag_queue, q);
145	return (fq->id == arg->id &&
146			ipv6_addr_equal(&fq->saddr, arg->src) &&
147			ipv6_addr_equal(&fq->daddr, arg->dst));
148}
149EXPORT_SYMBOL(ip6_frag_match);
150
151/* Memory Tracking Functions. */
152static inline void frag_kfree_skb(struct sk_buff *skb, int *work)
153{
154	if (work)
155		*work -= skb->truesize;
156	atomic_sub(skb->truesize, &ip6_frags.mem);
157	kfree_skb(skb);
158}
159
160void ip6_frag_init(struct inet_frag_queue *q, void *a)
161{
162	struct frag_queue *fq = container_of(q, struct frag_queue, q);
163	struct ip6_create_arg *arg = a;
164
165	fq->id = arg->id;
166	ipv6_addr_copy(&fq->saddr, arg->src);
167	ipv6_addr_copy(&fq->daddr, arg->dst);
168}
169EXPORT_SYMBOL(ip6_frag_init);
170
171/* Destruction primitives. */
172
173static __inline__ void fq_put(struct frag_queue *fq)
174{
175	inet_frag_put(&fq->q, &ip6_frags);
176}
177
178/* Kill fq entry. It is not destroyed immediately,
179 * because caller (and someone more) holds reference count.
180 */
181static __inline__ void fq_kill(struct frag_queue *fq)
182{
183	inet_frag_kill(&fq->q, &ip6_frags);
184}
185
186static void ip6_evictor(struct inet6_dev *idev)
187{
188	int evicted;
189
190	evicted = inet_frag_evictor(&ip6_frags);
191	if (evicted)
192		IP6_ADD_STATS_BH(idev, IPSTATS_MIB_REASMFAILS, evicted);
193}
194
195static void ip6_frag_expire(unsigned long data)
196{
197	struct frag_queue *fq;
198	struct net_device *dev = NULL;
199
200	fq = container_of((struct inet_frag_queue *)data, struct frag_queue, q);
201
202	spin_lock(&fq->q.lock);
203
204	if (fq->q.last_in & COMPLETE)
205		goto out;
206
207	fq_kill(fq);
208
209	dev = dev_get_by_index(&init_net, fq->iif);
210	if (!dev)
211		goto out;
212
213	rcu_read_lock();
214	IP6_INC_STATS_BH(__in6_dev_get(dev), IPSTATS_MIB_REASMTIMEOUT);
215	IP6_INC_STATS_BH(__in6_dev_get(dev), IPSTATS_MIB_REASMFAILS);
216	rcu_read_unlock();
217
218	/* Don't send error if the first segment did not arrive. */
219	if (!(fq->q.last_in&FIRST_IN) || !fq->q.fragments)
220		goto out;
221
222	/*
223	   But use as source device on which LAST ARRIVED
224	   segment was received. And do not use fq->dev
225	   pointer directly, device might already disappeared.
226	 */
227	fq->q.fragments->dev = dev;
228	icmpv6_send(fq->q.fragments, ICMPV6_TIME_EXCEED, ICMPV6_EXC_FRAGTIME, 0, dev);
229out:
230	if (dev)
231		dev_put(dev);
232	spin_unlock(&fq->q.lock);
233	fq_put(fq);
234}
235
236static __inline__ struct frag_queue *
237fq_find(struct net *net, __be32 id, struct in6_addr *src, struct in6_addr *dst,
238	struct inet6_dev *idev)
239{
240	struct inet_frag_queue *q;
241	struct ip6_create_arg arg;
242	unsigned int hash;
243
244	arg.id = id;
245	arg.src = src;
246	arg.dst = dst;
247	hash = ip6qhashfn(id, src, dst);
248
249	q = inet_frag_find(&net->ipv6.frags, &ip6_frags, &arg, hash);
250	if (q == NULL)
251		goto oom;
252
253	return container_of(q, struct frag_queue, q);
254
255oom:
256	IP6_INC_STATS_BH(idev, IPSTATS_MIB_REASMFAILS);
257	return NULL;
258}
259
260static int ip6_frag_queue(struct frag_queue *fq, struct sk_buff *skb,
261			   struct frag_hdr *fhdr, int nhoff)
262{
263	struct sk_buff *prev, *next;
264	struct net_device *dev;
265	int offset, end;
266
267	if (fq->q.last_in & COMPLETE)
268		goto err;
269
270	offset = ntohs(fhdr->frag_off) & ~0x7;
271	end = offset + (ntohs(ipv6_hdr(skb)->payload_len) -
272			((u8 *)(fhdr + 1) - (u8 *)(ipv6_hdr(skb) + 1)));
273
274	if ((unsigned int)end > IPV6_MAXPLEN) {
275		IP6_INC_STATS_BH(ip6_dst_idev(skb->dst),
276				 IPSTATS_MIB_INHDRERRORS);
277		icmpv6_param_prob(skb, ICMPV6_HDR_FIELD,
278				  ((u8 *)&fhdr->frag_off -
279				   skb_network_header(skb)));
280		return -1;
281	}
282
283	if (skb->ip_summed == CHECKSUM_COMPLETE) {
284		const unsigned char *nh = skb_network_header(skb);
285		skb->csum = csum_sub(skb->csum,
286				     csum_partial(nh, (u8 *)(fhdr + 1) - nh,
287						  0));
288	}
289
290	/* Is this the final fragment? */
291	if (!(fhdr->frag_off & htons(IP6_MF))) {
292		/* If we already have some bits beyond end
293		 * or have different end, the segment is corrupted.
294		 */
295		if (end < fq->q.len ||
296		    ((fq->q.last_in & LAST_IN) && end != fq->q.len))
297			goto err;
298		fq->q.last_in |= LAST_IN;
299		fq->q.len = end;
300	} else {
301		/* Check if the fragment is rounded to 8 bytes.
302		 * Required by the RFC.
303		 */
304		if (end & 0x7) {
305			/* RFC2460 says always send parameter problem in
306			 * this case. -DaveM
307			 */
308			IP6_INC_STATS_BH(ip6_dst_idev(skb->dst),
309					 IPSTATS_MIB_INHDRERRORS);
310			icmpv6_param_prob(skb, ICMPV6_HDR_FIELD,
311					  offsetof(struct ipv6hdr, payload_len));
312			return -1;
313		}
314		if (end > fq->q.len) {
315			/* Some bits beyond end -> corruption. */
316			if (fq->q.last_in & LAST_IN)
317				goto err;
318			fq->q.len = end;
319		}
320	}
321
322	if (end == offset)
323		goto err;
324
325	/* Point into the IP datagram 'data' part. */
326	if (!pskb_pull(skb, (u8 *) (fhdr + 1) - skb->data))
327		goto err;
328
329	if (pskb_trim_rcsum(skb, end - offset))
330		goto err;
331
332	/* Find out which fragments are in front and at the back of us
333	 * in the chain of fragments so far.  We must know where to put
334	 * this fragment, right?
335	 */
336	prev = NULL;
337	for(next = fq->q.fragments; next != NULL; next = next->next) {
338		if (FRAG6_CB(next)->offset >= offset)
339			break;	/* bingo! */
340		prev = next;
341	}
342
343	/* We found where to put this one.  Check for overlap with
344	 * preceding fragment, and, if needed, align things so that
345	 * any overlaps are eliminated.
346	 */
347	if (prev) {
348		int i = (FRAG6_CB(prev)->offset + prev->len) - offset;
349
350		if (i > 0) {
351			offset += i;
352			if (end <= offset)
353				goto err;
354			if (!pskb_pull(skb, i))
355				goto err;
356			if (skb->ip_summed != CHECKSUM_UNNECESSARY)
357				skb->ip_summed = CHECKSUM_NONE;
358		}
359	}
360
361	/* Look for overlap with succeeding segments.
362	 * If we can merge fragments, do it.
363	 */
364	while (next && FRAG6_CB(next)->offset < end) {
365		int i = end - FRAG6_CB(next)->offset; /* overlap is 'i' bytes */
366
367		if (i < next->len) {
368			/* Eat head of the next overlapped fragment
369			 * and leave the loop. The next ones cannot overlap.
370			 */
371			if (!pskb_pull(next, i))
372				goto err;
373			FRAG6_CB(next)->offset += i;	/* next fragment */
374			fq->q.meat -= i;
375			if (next->ip_summed != CHECKSUM_UNNECESSARY)
376				next->ip_summed = CHECKSUM_NONE;
377			break;
378		} else {
379			struct sk_buff *free_it = next;
380
381			/* Old fragment is completely overridden with
382			 * new one drop it.
383			 */
384			next = next->next;
385
386			if (prev)
387				prev->next = next;
388			else
389				fq->q.fragments = next;
390
391			fq->q.meat -= free_it->len;
392			frag_kfree_skb(free_it, NULL);
393		}
394	}
395
396	FRAG6_CB(skb)->offset = offset;
397
398	/* Insert this fragment in the chain of fragments. */
399	skb->next = next;
400	if (prev)
401		prev->next = skb;
402	else
403		fq->q.fragments = skb;
404
405	dev = skb->dev;
406	if (dev) {
407		fq->iif = dev->ifindex;
408		skb->dev = NULL;
409	}
410	fq->q.stamp = skb->tstamp;
411	fq->q.meat += skb->len;
412	atomic_add(skb->truesize, &ip6_frags.mem);
413
414	/* The first fragment.
415	 * nhoffset is obtained from the first fragment, of course.
416	 */
417	if (offset == 0) {
418		fq->nhoffset = nhoff;
419		fq->q.last_in |= FIRST_IN;
420	}
421
422	if (fq->q.last_in == (FIRST_IN | LAST_IN) && fq->q.meat == fq->q.len)
423		return ip6_frag_reasm(fq, prev, dev);
424
425	write_lock(&ip6_frags.lock);
426	list_move_tail(&fq->q.lru_list, &ip6_frags.lru_list);
427	write_unlock(&ip6_frags.lock);
428	return -1;
429
430err:
431	IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_REASMFAILS);
432	kfree_skb(skb);
433	return -1;
434}
435
436/*
437 *	Check if this packet is complete.
438 *	Returns NULL on failure by any reason, and pointer
439 *	to current nexthdr field in reassembled frame.
440 *
441 *	It is called with locked fq, and caller must check that
442 *	queue is eligible for reassembly i.e. it is not COMPLETE,
443 *	the last and the first frames arrived and all the bits are here.
444 */
445static int ip6_frag_reasm(struct frag_queue *fq, struct sk_buff *prev,
446			  struct net_device *dev)
447{
448	struct sk_buff *fp, *head = fq->q.fragments;
449	int    payload_len;
450	unsigned int nhoff;
451
452	fq_kill(fq);
453
454	/* Make the one we just received the head. */
455	if (prev) {
456		head = prev->next;
457		fp = skb_clone(head, GFP_ATOMIC);
458
459		if (!fp)
460			goto out_oom;
461
462		fp->next = head->next;
463		prev->next = fp;
464
465		skb_morph(head, fq->q.fragments);
466		head->next = fq->q.fragments->next;
467
468		kfree_skb(fq->q.fragments);
469		fq->q.fragments = head;
470	}
471
472	BUG_TRAP(head != NULL);
473	BUG_TRAP(FRAG6_CB(head)->offset == 0);
474
475	/* Unfragmented part is taken from the first segment. */
476	payload_len = ((head->data - skb_network_header(head)) -
477		       sizeof(struct ipv6hdr) + fq->q.len -
478		       sizeof(struct frag_hdr));
479	if (payload_len > IPV6_MAXPLEN)
480		goto out_oversize;
481
482	/* Head of list must not be cloned. */
483	if (skb_cloned(head) && pskb_expand_head(head, 0, 0, GFP_ATOMIC))
484		goto out_oom;
485
486	/* If the first fragment is fragmented itself, we split
487	 * it to two chunks: the first with data and paged part
488	 * and the second, holding only fragments. */
489	if (skb_shinfo(head)->frag_list) {
490		struct sk_buff *clone;
491		int i, plen = 0;
492
493		if ((clone = alloc_skb(0, GFP_ATOMIC)) == NULL)
494			goto out_oom;
495		clone->next = head->next;
496		head->next = clone;
497		skb_shinfo(clone)->frag_list = skb_shinfo(head)->frag_list;
498		skb_shinfo(head)->frag_list = NULL;
499		for (i=0; i<skb_shinfo(head)->nr_frags; i++)
500			plen += skb_shinfo(head)->frags[i].size;
501		clone->len = clone->data_len = head->data_len - plen;
502		head->data_len -= clone->len;
503		head->len -= clone->len;
504		clone->csum = 0;
505		clone->ip_summed = head->ip_summed;
506		atomic_add(clone->truesize, &ip6_frags.mem);
507	}
508
509	/* We have to remove fragment header from datagram and to relocate
510	 * header in order to calculate ICV correctly. */
511	nhoff = fq->nhoffset;
512	skb_network_header(head)[nhoff] = skb_transport_header(head)[0];
513	memmove(head->head + sizeof(struct frag_hdr), head->head,
514		(head->data - head->head) - sizeof(struct frag_hdr));
515	head->mac_header += sizeof(struct frag_hdr);
516	head->network_header += sizeof(struct frag_hdr);
517
518	skb_shinfo(head)->frag_list = head->next;
519	skb_reset_transport_header(head);
520	skb_push(head, head->data - skb_network_header(head));
521	atomic_sub(head->truesize, &ip6_frags.mem);
522
523	for (fp=head->next; fp; fp = fp->next) {
524		head->data_len += fp->len;
525		head->len += fp->len;
526		if (head->ip_summed != fp->ip_summed)
527			head->ip_summed = CHECKSUM_NONE;
528		else if (head->ip_summed == CHECKSUM_COMPLETE)
529			head->csum = csum_add(head->csum, fp->csum);
530		head->truesize += fp->truesize;
531		atomic_sub(fp->truesize, &ip6_frags.mem);
532	}
533
534	head->next = NULL;
535	head->dev = dev;
536	head->tstamp = fq->q.stamp;
537	ipv6_hdr(head)->payload_len = htons(payload_len);
538	IP6CB(head)->nhoff = nhoff;
539
540	/* Yes, and fold redundant checksum back. 8) */
541	if (head->ip_summed == CHECKSUM_COMPLETE)
542		head->csum = csum_partial(skb_network_header(head),
543					  skb_network_header_len(head),
544					  head->csum);
545
546	rcu_read_lock();
547	IP6_INC_STATS_BH(__in6_dev_get(dev), IPSTATS_MIB_REASMOKS);
548	rcu_read_unlock();
549	fq->q.fragments = NULL;
550	return 1;
551
552out_oversize:
553	if (net_ratelimit())
554		printk(KERN_DEBUG "ip6_frag_reasm: payload len = %d\n", payload_len);
555	goto out_fail;
556out_oom:
557	if (net_ratelimit())
558		printk(KERN_DEBUG "ip6_frag_reasm: no memory for reassembly\n");
559out_fail:
560	rcu_read_lock();
561	IP6_INC_STATS_BH(__in6_dev_get(dev), IPSTATS_MIB_REASMFAILS);
562	rcu_read_unlock();
563	return -1;
564}
565
566static int ipv6_frag_rcv(struct sk_buff *skb)
567{
568	struct frag_hdr *fhdr;
569	struct frag_queue *fq;
570	struct ipv6hdr *hdr = ipv6_hdr(skb);
571	struct net *net;
572
573	IP6_INC_STATS_BH(ip6_dst_idev(skb->dst), IPSTATS_MIB_REASMREQDS);
574
575	/* Jumbo payload inhibits frag. header */
576	if (hdr->payload_len==0) {
577		IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_INHDRERRORS);
578		icmpv6_param_prob(skb, ICMPV6_HDR_FIELD,
579				  skb_network_header_len(skb));
580		return -1;
581	}
582	if (!pskb_may_pull(skb, (skb_transport_offset(skb) +
583				 sizeof(struct frag_hdr)))) {
584		IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_INHDRERRORS);
585		icmpv6_param_prob(skb, ICMPV6_HDR_FIELD,
586				  skb_network_header_len(skb));
587		return -1;
588	}
589
590	hdr = ipv6_hdr(skb);
591	fhdr = (struct frag_hdr *)skb_transport_header(skb);
592
593	if (!(fhdr->frag_off & htons(0xFFF9))) {
594		/* It is not a fragmented frame */
595		skb->transport_header += sizeof(struct frag_hdr);
596		IP6_INC_STATS_BH(ip6_dst_idev(skb->dst), IPSTATS_MIB_REASMOKS);
597
598		IP6CB(skb)->nhoff = (u8 *)fhdr - skb_network_header(skb);
599		return 1;
600	}
601
602	net = skb->dev->nd_net;
603	if (atomic_read(&ip6_frags.mem) > init_net.ipv6.sysctl.frags.high_thresh)
604		ip6_evictor(ip6_dst_idev(skb->dst));
605
606	if ((fq = fq_find(net, fhdr->identification, &hdr->saddr, &hdr->daddr,
607			  ip6_dst_idev(skb->dst))) != NULL) {
608		int ret;
609
610		spin_lock(&fq->q.lock);
611
612		ret = ip6_frag_queue(fq, skb, fhdr, IP6CB(skb)->nhoff);
613
614		spin_unlock(&fq->q.lock);
615		fq_put(fq);
616		return ret;
617	}
618
619	IP6_INC_STATS_BH(ip6_dst_idev(skb->dst), IPSTATS_MIB_REASMFAILS);
620	kfree_skb(skb);
621	return -1;
622}
623
624static struct inet6_protocol frag_protocol =
625{
626	.handler	=	ipv6_frag_rcv,
627	.flags		=	INET6_PROTO_NOPOLICY,
628};
629
630#ifdef CONFIG_SYSCTL
631static struct ctl_table ip6_frags_ctl_table[] = {
632	{
633		.ctl_name	= NET_IPV6_IP6FRAG_HIGH_THRESH,
634		.procname	= "ip6frag_high_thresh",
635		.data		= &init_net.ipv6.sysctl.frags.high_thresh,
636		.maxlen		= sizeof(int),
637		.mode		= 0644,
638		.proc_handler	= &proc_dointvec
639	},
640	{
641		.ctl_name	= NET_IPV6_IP6FRAG_LOW_THRESH,
642		.procname	= "ip6frag_low_thresh",
643		.data		= &init_net.ipv6.sysctl.frags.low_thresh,
644		.maxlen		= sizeof(int),
645		.mode		= 0644,
646		.proc_handler	= &proc_dointvec
647	},
648	{
649		.ctl_name	= NET_IPV6_IP6FRAG_TIME,
650		.procname	= "ip6frag_time",
651		.data		= &init_net.ipv6.sysctl.frags.timeout,
652		.maxlen		= sizeof(int),
653		.mode		= 0644,
654		.proc_handler	= &proc_dointvec_jiffies,
655		.strategy	= &sysctl_jiffies,
656	},
657	{
658		.ctl_name	= NET_IPV6_IP6FRAG_SECRET_INTERVAL,
659		.procname	= "ip6frag_secret_interval",
660		.data		= &init_net.ipv6.sysctl.frags.secret_interval,
661		.maxlen		= sizeof(int),
662		.mode		= 0644,
663		.proc_handler	= &proc_dointvec_jiffies,
664		.strategy	= &sysctl_jiffies
665	},
666	{ }
667};
668
669static int ip6_frags_sysctl_register(struct net *net)
670{
671	struct ctl_table_header *hdr;
672
673	hdr = register_net_sysctl_table(net, net_ipv6_ctl_path,
674			ip6_frags_ctl_table);
675	return hdr == NULL ? -ENOMEM : 0;
676}
677#else
678static inline int ip6_frags_sysctl_register(struct net *net)
679{
680	return 0;
681}
682#endif
683
684static int ipv6_frags_init_net(struct net *net)
685{
686	ip6_frags.ctl = &net->ipv6.sysctl.frags;
687
688	net->ipv6.sysctl.frags.high_thresh = 256 * 1024;
689	net->ipv6.sysctl.frags.low_thresh = 192 * 1024;
690	net->ipv6.sysctl.frags.timeout = IPV6_FRAG_TIMEOUT;
691	net->ipv6.sysctl.frags.secret_interval = 10 * 60 * HZ;
692
693	return ip6_frags_sysctl_register(net);
694}
695
696int __init ipv6_frag_init(void)
697{
698	int ret;
699
700	ret = inet6_add_protocol(&frag_protocol, IPPROTO_FRAGMENT);
701	if (ret)
702		goto out;
703
704	ipv6_frags_init_net(&init_net);
705
706	ip6_frags.hashfn = ip6_hashfn;
707	ip6_frags.constructor = ip6_frag_init;
708	ip6_frags.destructor = NULL;
709	ip6_frags.skb_free = NULL;
710	ip6_frags.qsize = sizeof(struct frag_queue);
711	ip6_frags.match = ip6_frag_match;
712	ip6_frags.frag_expire = ip6_frag_expire;
713	inet_frags_init(&ip6_frags);
714out:
715	return ret;
716}
717
718void ipv6_frag_exit(void)
719{
720	inet_frags_fini(&ip6_frags);
721	inet6_del_protocol(&frag_protocol, IPPROTO_FRAGMENT);
722}
723