1/*
2 *	ip6_flowlabel.c		IPv6 flowlabel manager.
3 *
4 *	This program is free software; you can redistribute it and/or
5 *      modify it under the terms of the GNU General Public License
6 *      as published by the Free Software Foundation; either version
7 *      2 of the License, or (at your option) any later version.
8 *
9 *	Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
10 */
11
12#include <linux/capability.h>
13#include <linux/errno.h>
14#include <linux/types.h>
15#include <linux/socket.h>
16#include <linux/net.h>
17#include <linux/netdevice.h>
18#include <linux/if_arp.h>
19#include <linux/in6.h>
20#include <linux/route.h>
21#include <linux/proc_fs.h>
22#include <linux/seq_file.h>
23#include <linux/slab.h>
24
25#include <net/net_namespace.h>
26#include <net/sock.h>
27
28#include <net/ipv6.h>
29#include <net/ndisc.h>
30#include <net/protocol.h>
31#include <net/ip6_route.h>
32#include <net/addrconf.h>
33#include <net/rawv6.h>
34#include <net/icmp.h>
35#include <net/transp_v6.h>
36
37#include <asm/uaccess.h>
38
39#define FL_MIN_LINGER	6	/* Minimal linger. It is set to 6sec specified
40				   in old IPv6 RFC. Well, it was reasonable value.
41				 */
42#define FL_MAX_LINGER	60	/* Maximal linger timeout */
43
44/* FL hash table */
45
46#define FL_MAX_PER_SOCK	32
47#define FL_MAX_SIZE	4096
48#define FL_HASH_MASK	255
49#define FL_HASH(l)	(ntohl(l)&FL_HASH_MASK)
50
51static atomic_t fl_size = ATOMIC_INIT(0);
52static struct ip6_flowlabel *fl_ht[FL_HASH_MASK+1];
53
54static void ip6_fl_gc(unsigned long dummy);
55static DEFINE_TIMER(ip6_fl_gc_timer, ip6_fl_gc, 0, 0);
56
57/* FL hash table lock: it protects only of GC */
58
59static DEFINE_RWLOCK(ip6_fl_lock);
60
61/* Big socket sock */
62
63static DEFINE_RWLOCK(ip6_sk_fl_lock);
64
65
66static inline struct ip6_flowlabel *__fl_lookup(struct net *net, __be32 label)
67{
68	struct ip6_flowlabel *fl;
69
70	for (fl=fl_ht[FL_HASH(label)]; fl; fl = fl->next) {
71		if (fl->label == label && net_eq(fl->fl_net, net))
72			return fl;
73	}
74	return NULL;
75}
76
77static struct ip6_flowlabel *fl_lookup(struct net *net, __be32 label)
78{
79	struct ip6_flowlabel *fl;
80
81	read_lock_bh(&ip6_fl_lock);
82	fl = __fl_lookup(net, label);
83	if (fl)
84		atomic_inc(&fl->users);
85	read_unlock_bh(&ip6_fl_lock);
86	return fl;
87}
88
89
90static void fl_free(struct ip6_flowlabel *fl)
91{
92	if (fl) {
93		release_net(fl->fl_net);
94		kfree(fl->opt);
95	}
96	kfree(fl);
97}
98
99static void fl_release(struct ip6_flowlabel *fl)
100{
101	write_lock_bh(&ip6_fl_lock);
102
103	fl->lastuse = jiffies;
104	if (atomic_dec_and_test(&fl->users)) {
105		unsigned long ttd = fl->lastuse + fl->linger;
106		if (time_after(ttd, fl->expires))
107			fl->expires = ttd;
108		ttd = fl->expires;
109		if (fl->opt && fl->share == IPV6_FL_S_EXCL) {
110			struct ipv6_txoptions *opt = fl->opt;
111			fl->opt = NULL;
112			kfree(opt);
113		}
114		if (!timer_pending(&ip6_fl_gc_timer) ||
115		    time_after(ip6_fl_gc_timer.expires, ttd))
116			mod_timer(&ip6_fl_gc_timer, ttd);
117	}
118	write_unlock_bh(&ip6_fl_lock);
119}
120
121static void ip6_fl_gc(unsigned long dummy)
122{
123	int i;
124	unsigned long now = jiffies;
125	unsigned long sched = 0;
126
127	write_lock(&ip6_fl_lock);
128
129	for (i=0; i<=FL_HASH_MASK; i++) {
130		struct ip6_flowlabel *fl, **flp;
131		flp = &fl_ht[i];
132		while ((fl=*flp) != NULL) {
133			if (atomic_read(&fl->users) == 0) {
134				unsigned long ttd = fl->lastuse + fl->linger;
135				if (time_after(ttd, fl->expires))
136					fl->expires = ttd;
137				ttd = fl->expires;
138				if (time_after_eq(now, ttd)) {
139					*flp = fl->next;
140					fl_free(fl);
141					atomic_dec(&fl_size);
142					continue;
143				}
144				if (!sched || time_before(ttd, sched))
145					sched = ttd;
146			}
147			flp = &fl->next;
148		}
149	}
150	if (!sched && atomic_read(&fl_size))
151		sched = now + FL_MAX_LINGER;
152	if (sched) {
153		mod_timer(&ip6_fl_gc_timer, sched);
154	}
155	write_unlock(&ip6_fl_lock);
156}
157
158static void __net_exit ip6_fl_purge(struct net *net)
159{
160	int i;
161
162	write_lock(&ip6_fl_lock);
163	for (i = 0; i <= FL_HASH_MASK; i++) {
164		struct ip6_flowlabel *fl, **flp;
165		flp = &fl_ht[i];
166		while ((fl = *flp) != NULL) {
167			if (net_eq(fl->fl_net, net) &&
168			    atomic_read(&fl->users) == 0) {
169				*flp = fl->next;
170				fl_free(fl);
171				atomic_dec(&fl_size);
172				continue;
173			}
174			flp = &fl->next;
175		}
176	}
177	write_unlock(&ip6_fl_lock);
178}
179
180static struct ip6_flowlabel *fl_intern(struct net *net,
181				       struct ip6_flowlabel *fl, __be32 label)
182{
183	struct ip6_flowlabel *lfl;
184
185	fl->label = label & IPV6_FLOWLABEL_MASK;
186
187	write_lock_bh(&ip6_fl_lock);
188	if (label == 0) {
189		for (;;) {
190			fl->label = htonl(net_random())&IPV6_FLOWLABEL_MASK;
191			if (fl->label) {
192				lfl = __fl_lookup(net, fl->label);
193				if (lfl == NULL)
194					break;
195			}
196		}
197	} else {
198		/*
199		 * we dropper the ip6_fl_lock, so this entry could reappear
200		 * and we need to recheck with it.
201		 *
202		 * OTOH no need to search the active socket first, like it is
203		 * done in ipv6_flowlabel_opt - sock is locked, so new entry
204		 * with the same label can only appear on another sock
205		 */
206		lfl = __fl_lookup(net, fl->label);
207		if (lfl != NULL) {
208			atomic_inc(&lfl->users);
209			write_unlock_bh(&ip6_fl_lock);
210			return lfl;
211		}
212	}
213
214	fl->lastuse = jiffies;
215	fl->next = fl_ht[FL_HASH(fl->label)];
216	fl_ht[FL_HASH(fl->label)] = fl;
217	atomic_inc(&fl_size);
218	write_unlock_bh(&ip6_fl_lock);
219	return NULL;
220}
221
222
223
224/* Socket flowlabel lists */
225
226struct ip6_flowlabel * fl6_sock_lookup(struct sock *sk, __be32 label)
227{
228	struct ipv6_fl_socklist *sfl;
229	struct ipv6_pinfo *np = inet6_sk(sk);
230
231	label &= IPV6_FLOWLABEL_MASK;
232
233	read_lock_bh(&ip6_sk_fl_lock);
234	for (sfl=np->ipv6_fl_list; sfl; sfl = sfl->next) {
235		struct ip6_flowlabel *fl = sfl->fl;
236		if (fl->label == label) {
237			fl->lastuse = jiffies;
238			atomic_inc(&fl->users);
239			read_unlock_bh(&ip6_sk_fl_lock);
240			return fl;
241		}
242	}
243	read_unlock_bh(&ip6_sk_fl_lock);
244	return NULL;
245}
246
247EXPORT_SYMBOL_GPL(fl6_sock_lookup);
248
249void fl6_free_socklist(struct sock *sk)
250{
251	struct ipv6_pinfo *np = inet6_sk(sk);
252	struct ipv6_fl_socklist *sfl;
253
254	while ((sfl = np->ipv6_fl_list) != NULL) {
255		np->ipv6_fl_list = sfl->next;
256		fl_release(sfl->fl);
257		kfree(sfl);
258	}
259}
260
261/* Service routines */
262
263
264/*
265   It is the only difficult place. flowlabel enforces equal headers
266   before and including routing header, however user may supply options
267   following rthdr.
268 */
269
270struct ipv6_txoptions *fl6_merge_options(struct ipv6_txoptions * opt_space,
271					 struct ip6_flowlabel * fl,
272					 struct ipv6_txoptions * fopt)
273{
274	struct ipv6_txoptions * fl_opt = fl->opt;
275
276	if (fopt == NULL || fopt->opt_flen == 0)
277		return fl_opt;
278
279	if (fl_opt != NULL) {
280		opt_space->hopopt = fl_opt->hopopt;
281		opt_space->dst0opt = fl_opt->dst0opt;
282		opt_space->srcrt = fl_opt->srcrt;
283		opt_space->opt_nflen = fl_opt->opt_nflen;
284	} else {
285		if (fopt->opt_nflen == 0)
286			return fopt;
287		opt_space->hopopt = NULL;
288		opt_space->dst0opt = NULL;
289		opt_space->srcrt = NULL;
290		opt_space->opt_nflen = 0;
291	}
292	opt_space->dst1opt = fopt->dst1opt;
293	opt_space->opt_flen = fopt->opt_flen;
294	return opt_space;
295}
296
297static unsigned long check_linger(unsigned long ttl)
298{
299	if (ttl < FL_MIN_LINGER)
300		return FL_MIN_LINGER*HZ;
301	if (ttl > FL_MAX_LINGER && !capable(CAP_NET_ADMIN))
302		return 0;
303	return ttl*HZ;
304}
305
306static int fl6_renew(struct ip6_flowlabel *fl, unsigned long linger, unsigned long expires)
307{
308	linger = check_linger(linger);
309	if (!linger)
310		return -EPERM;
311	expires = check_linger(expires);
312	if (!expires)
313		return -EPERM;
314	fl->lastuse = jiffies;
315	if (time_before(fl->linger, linger))
316		fl->linger = linger;
317	if (time_before(expires, fl->linger))
318		expires = fl->linger;
319	if (time_before(fl->expires, fl->lastuse + expires))
320		fl->expires = fl->lastuse + expires;
321	return 0;
322}
323
324static struct ip6_flowlabel *
325fl_create(struct net *net, struct in6_flowlabel_req *freq, char __user *optval,
326	  int optlen, int *err_p)
327{
328	struct ip6_flowlabel *fl = NULL;
329	int olen;
330	int addr_type;
331	int err;
332
333	olen = optlen - CMSG_ALIGN(sizeof(*freq));
334	err = -EINVAL;
335	if (olen > 64 * 1024)
336		goto done;
337
338	err = -ENOMEM;
339	fl = kzalloc(sizeof(*fl), GFP_KERNEL);
340	if (fl == NULL)
341		goto done;
342
343	if (olen > 0) {
344		struct msghdr msg;
345		struct flowi flowi;
346		int junk;
347
348		err = -ENOMEM;
349		fl->opt = kmalloc(sizeof(*fl->opt) + olen, GFP_KERNEL);
350		if (fl->opt == NULL)
351			goto done;
352
353		memset(fl->opt, 0, sizeof(*fl->opt));
354		fl->opt->tot_len = sizeof(*fl->opt) + olen;
355		err = -EFAULT;
356		if (copy_from_user(fl->opt+1, optval+CMSG_ALIGN(sizeof(*freq)), olen))
357			goto done;
358
359		msg.msg_controllen = olen;
360		msg.msg_control = (void*)(fl->opt+1);
361		flowi.oif = 0;
362
363		err = datagram_send_ctl(net, &msg, &flowi, fl->opt, &junk,
364					&junk, &junk);
365		if (err)
366			goto done;
367		err = -EINVAL;
368		if (fl->opt->opt_flen)
369			goto done;
370		if (fl->opt->opt_nflen == 0) {
371			kfree(fl->opt);
372			fl->opt = NULL;
373		}
374	}
375
376	fl->fl_net = hold_net(net);
377	fl->expires = jiffies;
378	err = fl6_renew(fl, freq->flr_linger, freq->flr_expires);
379	if (err)
380		goto done;
381	fl->share = freq->flr_share;
382	addr_type = ipv6_addr_type(&freq->flr_dst);
383	if ((addr_type & IPV6_ADDR_MAPPED) ||
384	    addr_type == IPV6_ADDR_ANY) {
385		err = -EINVAL;
386		goto done;
387	}
388	ipv6_addr_copy(&fl->dst, &freq->flr_dst);
389	atomic_set(&fl->users, 1);
390	switch (fl->share) {
391	case IPV6_FL_S_EXCL:
392	case IPV6_FL_S_ANY:
393		break;
394	case IPV6_FL_S_PROCESS:
395		fl->owner = current->pid;
396		break;
397	case IPV6_FL_S_USER:
398		fl->owner = current_euid();
399		break;
400	default:
401		err = -EINVAL;
402		goto done;
403	}
404	return fl;
405
406done:
407	fl_free(fl);
408	*err_p = err;
409	return NULL;
410}
411
412static int mem_check(struct sock *sk)
413{
414	struct ipv6_pinfo *np = inet6_sk(sk);
415	struct ipv6_fl_socklist *sfl;
416	int room = FL_MAX_SIZE - atomic_read(&fl_size);
417	int count = 0;
418
419	if (room > FL_MAX_SIZE - FL_MAX_PER_SOCK)
420		return 0;
421
422	for (sfl = np->ipv6_fl_list; sfl; sfl = sfl->next)
423		count++;
424
425	if (room <= 0 ||
426	    ((count >= FL_MAX_PER_SOCK ||
427	      (count > 0 && room < FL_MAX_SIZE/2) || room < FL_MAX_SIZE/4) &&
428	     !capable(CAP_NET_ADMIN)))
429		return -ENOBUFS;
430
431	return 0;
432}
433
434static int ipv6_hdr_cmp(struct ipv6_opt_hdr *h1, struct ipv6_opt_hdr *h2)
435{
436	if (h1 == h2)
437		return 0;
438	if (h1 == NULL || h2 == NULL)
439		return 1;
440	if (h1->hdrlen != h2->hdrlen)
441		return 1;
442	return memcmp(h1+1, h2+1, ((h1->hdrlen+1)<<3) - sizeof(*h1));
443}
444
445static int ipv6_opt_cmp(struct ipv6_txoptions *o1, struct ipv6_txoptions *o2)
446{
447	if (o1 == o2)
448		return 0;
449	if (o1 == NULL || o2 == NULL)
450		return 1;
451	if (o1->opt_nflen != o2->opt_nflen)
452		return 1;
453	if (ipv6_hdr_cmp(o1->hopopt, o2->hopopt))
454		return 1;
455	if (ipv6_hdr_cmp(o1->dst0opt, o2->dst0opt))
456		return 1;
457	if (ipv6_hdr_cmp((struct ipv6_opt_hdr *)o1->srcrt, (struct ipv6_opt_hdr *)o2->srcrt))
458		return 1;
459	return 0;
460}
461
462static inline void fl_link(struct ipv6_pinfo *np, struct ipv6_fl_socklist *sfl,
463		struct ip6_flowlabel *fl)
464{
465	write_lock_bh(&ip6_sk_fl_lock);
466	sfl->fl = fl;
467	sfl->next = np->ipv6_fl_list;
468	np->ipv6_fl_list = sfl;
469	write_unlock_bh(&ip6_sk_fl_lock);
470}
471
472int ipv6_flowlabel_opt(struct sock *sk, char __user *optval, int optlen)
473{
474	int uninitialized_var(err);
475	struct net *net = sock_net(sk);
476	struct ipv6_pinfo *np = inet6_sk(sk);
477	struct in6_flowlabel_req freq;
478	struct ipv6_fl_socklist *sfl1=NULL;
479	struct ipv6_fl_socklist *sfl, **sflp;
480	struct ip6_flowlabel *fl, *fl1 = NULL;
481
482
483	if (optlen < sizeof(freq))
484		return -EINVAL;
485
486	if (copy_from_user(&freq, optval, sizeof(freq)))
487		return -EFAULT;
488
489	switch (freq.flr_action) {
490	case IPV6_FL_A_PUT:
491		write_lock_bh(&ip6_sk_fl_lock);
492		for (sflp = &np->ipv6_fl_list; (sfl=*sflp)!=NULL; sflp = &sfl->next) {
493			if (sfl->fl->label == freq.flr_label) {
494				if (freq.flr_label == (np->flow_label&IPV6_FLOWLABEL_MASK))
495					np->flow_label &= ~IPV6_FLOWLABEL_MASK;
496				*sflp = sfl->next;
497				write_unlock_bh(&ip6_sk_fl_lock);
498				fl_release(sfl->fl);
499				kfree(sfl);
500				return 0;
501			}
502		}
503		write_unlock_bh(&ip6_sk_fl_lock);
504		return -ESRCH;
505
506	case IPV6_FL_A_RENEW:
507		read_lock_bh(&ip6_sk_fl_lock);
508		for (sfl = np->ipv6_fl_list; sfl; sfl = sfl->next) {
509			if (sfl->fl->label == freq.flr_label) {
510				err = fl6_renew(sfl->fl, freq.flr_linger, freq.flr_expires);
511				read_unlock_bh(&ip6_sk_fl_lock);
512				return err;
513			}
514		}
515		read_unlock_bh(&ip6_sk_fl_lock);
516
517		if (freq.flr_share == IPV6_FL_S_NONE && capable(CAP_NET_ADMIN)) {
518			fl = fl_lookup(net, freq.flr_label);
519			if (fl) {
520				err = fl6_renew(fl, freq.flr_linger, freq.flr_expires);
521				fl_release(fl);
522				return err;
523			}
524		}
525		return -ESRCH;
526
527	case IPV6_FL_A_GET:
528		if (freq.flr_label & ~IPV6_FLOWLABEL_MASK)
529			return -EINVAL;
530
531		fl = fl_create(net, &freq, optval, optlen, &err);
532		if (fl == NULL)
533			return err;
534		sfl1 = kmalloc(sizeof(*sfl1), GFP_KERNEL);
535
536		if (freq.flr_label) {
537			err = -EEXIST;
538			read_lock_bh(&ip6_sk_fl_lock);
539			for (sfl = np->ipv6_fl_list; sfl; sfl = sfl->next) {
540				if (sfl->fl->label == freq.flr_label) {
541					if (freq.flr_flags&IPV6_FL_F_EXCL) {
542						read_unlock_bh(&ip6_sk_fl_lock);
543						goto done;
544					}
545					fl1 = sfl->fl;
546					atomic_inc(&fl1->users);
547					break;
548				}
549			}
550			read_unlock_bh(&ip6_sk_fl_lock);
551
552			if (fl1 == NULL)
553				fl1 = fl_lookup(net, freq.flr_label);
554			if (fl1) {
555recheck:
556				err = -EEXIST;
557				if (freq.flr_flags&IPV6_FL_F_EXCL)
558					goto release;
559				err = -EPERM;
560				if (fl1->share == IPV6_FL_S_EXCL ||
561				    fl1->share != fl->share ||
562				    fl1->owner != fl->owner)
563					goto release;
564
565				err = -EINVAL;
566				if (!ipv6_addr_equal(&fl1->dst, &fl->dst) ||
567				    ipv6_opt_cmp(fl1->opt, fl->opt))
568					goto release;
569
570				err = -ENOMEM;
571				if (sfl1 == NULL)
572					goto release;
573				if (fl->linger > fl1->linger)
574					fl1->linger = fl->linger;
575				if ((long)(fl->expires - fl1->expires) > 0)
576					fl1->expires = fl->expires;
577				fl_link(np, sfl1, fl1);
578				fl_free(fl);
579				return 0;
580
581release:
582				fl_release(fl1);
583				goto done;
584			}
585		}
586		err = -ENOENT;
587		if (!(freq.flr_flags&IPV6_FL_F_CREATE))
588			goto done;
589
590		err = -ENOMEM;
591		if (sfl1 == NULL || (err = mem_check(sk)) != 0)
592			goto done;
593
594		fl1 = fl_intern(net, fl, freq.flr_label);
595		if (fl1 != NULL)
596			goto recheck;
597
598		if (!freq.flr_label) {
599			if (copy_to_user(&((struct in6_flowlabel_req __user *) optval)->flr_label,
600					 &fl->label, sizeof(fl->label))) {
601				/* Intentionally ignore fault. */
602			}
603		}
604
605		fl_link(np, sfl1, fl);
606		return 0;
607
608	default:
609		return -EINVAL;
610	}
611
612done:
613	fl_free(fl);
614	kfree(sfl1);
615	return err;
616}
617
618#ifdef CONFIG_PROC_FS
619
620struct ip6fl_iter_state {
621	struct seq_net_private p;
622	int bucket;
623};
624
625#define ip6fl_seq_private(seq)	((struct ip6fl_iter_state *)(seq)->private)
626
627static struct ip6_flowlabel *ip6fl_get_first(struct seq_file *seq)
628{
629	struct ip6_flowlabel *fl = NULL;
630	struct ip6fl_iter_state *state = ip6fl_seq_private(seq);
631	struct net *net = seq_file_net(seq);
632
633	for (state->bucket = 0; state->bucket <= FL_HASH_MASK; ++state->bucket) {
634		fl = fl_ht[state->bucket];
635
636		while (fl && !net_eq(fl->fl_net, net))
637			fl = fl->next;
638		if (fl)
639			break;
640	}
641	return fl;
642}
643
644static struct ip6_flowlabel *ip6fl_get_next(struct seq_file *seq, struct ip6_flowlabel *fl)
645{
646	struct ip6fl_iter_state *state = ip6fl_seq_private(seq);
647	struct net *net = seq_file_net(seq);
648
649	fl = fl->next;
650try_again:
651	while (fl && !net_eq(fl->fl_net, net))
652		fl = fl->next;
653
654	while (!fl) {
655		if (++state->bucket <= FL_HASH_MASK) {
656			fl = fl_ht[state->bucket];
657			goto try_again;
658		} else
659			break;
660	}
661	return fl;
662}
663
664static struct ip6_flowlabel *ip6fl_get_idx(struct seq_file *seq, loff_t pos)
665{
666	struct ip6_flowlabel *fl = ip6fl_get_first(seq);
667	if (fl)
668		while (pos && (fl = ip6fl_get_next(seq, fl)) != NULL)
669			--pos;
670	return pos ? NULL : fl;
671}
672
673static void *ip6fl_seq_start(struct seq_file *seq, loff_t *pos)
674	__acquires(ip6_fl_lock)
675{
676	read_lock_bh(&ip6_fl_lock);
677	return *pos ? ip6fl_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
678}
679
680static void *ip6fl_seq_next(struct seq_file *seq, void *v, loff_t *pos)
681{
682	struct ip6_flowlabel *fl;
683
684	if (v == SEQ_START_TOKEN)
685		fl = ip6fl_get_first(seq);
686	else
687		fl = ip6fl_get_next(seq, v);
688	++*pos;
689	return fl;
690}
691
692static void ip6fl_seq_stop(struct seq_file *seq, void *v)
693	__releases(ip6_fl_lock)
694{
695	read_unlock_bh(&ip6_fl_lock);
696}
697
698static int ip6fl_seq_show(struct seq_file *seq, void *v)
699{
700	if (v == SEQ_START_TOKEN)
701		seq_printf(seq, "%-5s %-1s %-6s %-6s %-6s %-8s %-32s %s\n",
702			   "Label", "S", "Owner", "Users", "Linger", "Expires", "Dst", "Opt");
703	else {
704		struct ip6_flowlabel *fl = v;
705		seq_printf(seq,
706			   "%05X %-1d %-6d %-6d %-6ld %-8ld %pi6 %-4d\n",
707			   (unsigned)ntohl(fl->label),
708			   fl->share,
709			   (unsigned)fl->owner,
710			   atomic_read(&fl->users),
711			   fl->linger/HZ,
712			   (long)(fl->expires - jiffies)/HZ,
713			   &fl->dst,
714			   fl->opt ? fl->opt->opt_nflen : 0);
715	}
716	return 0;
717}
718
719static const struct seq_operations ip6fl_seq_ops = {
720	.start	=	ip6fl_seq_start,
721	.next	=	ip6fl_seq_next,
722	.stop	=	ip6fl_seq_stop,
723	.show	=	ip6fl_seq_show,
724};
725
726static int ip6fl_seq_open(struct inode *inode, struct file *file)
727{
728	return seq_open_net(inode, file, &ip6fl_seq_ops,
729			    sizeof(struct ip6fl_iter_state));
730}
731
732static const struct file_operations ip6fl_seq_fops = {
733	.owner		=	THIS_MODULE,
734	.open		=	ip6fl_seq_open,
735	.read		=	seq_read,
736	.llseek		=	seq_lseek,
737	.release	=	seq_release_net,
738};
739
740static int __net_init ip6_flowlabel_proc_init(struct net *net)
741{
742	if (!proc_net_fops_create(net, "ip6_flowlabel",
743				  S_IRUGO, &ip6fl_seq_fops))
744		return -ENOMEM;
745	return 0;
746}
747
748static void __net_exit ip6_flowlabel_proc_fini(struct net *net)
749{
750	proc_net_remove(net, "ip6_flowlabel");
751}
752#else
753static inline int ip6_flowlabel_proc_init(struct net *net)
754{
755	return 0;
756}
757static inline void ip6_flowlabel_proc_fini(struct net *net)
758{
759}
760#endif
761
762static void __net_exit ip6_flowlabel_net_exit(struct net *net)
763{
764	ip6_fl_purge(net);
765	ip6_flowlabel_proc_fini(net);
766}
767
768static struct pernet_operations ip6_flowlabel_net_ops = {
769	.init = ip6_flowlabel_proc_init,
770	.exit = ip6_flowlabel_net_exit,
771};
772
773int ip6_flowlabel_init(void)
774{
775	return register_pernet_subsys(&ip6_flowlabel_net_ops);
776}
777
778void ip6_flowlabel_cleanup(void)
779{
780	del_timer(&ip6_fl_gc_timer);
781	unregister_pernet_subsys(&ip6_flowlabel_net_ops);
782}
783