ipv6: When we droped a packet, we should return NET_RX_DROP instead of 0
[linux-2.6.git] / net / ipv6 / ip6_flowlabel.c
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
24 #include <net/net_namespace.h>
25 #include <net/sock.h>
26
27 #include <net/ipv6.h>
28 #include <net/ndisc.h>
29 #include <net/protocol.h>
30 #include <net/ip6_route.h>
31 #include <net/addrconf.h>
32 #include <net/rawv6.h>
33 #include <net/icmp.h>
34 #include <net/transp_v6.h>
35
36 #include <asm/uaccess.h>
37
38 #define FL_MIN_LINGER   6       /* Minimal linger. It is set to 6sec specified
39                                    in old IPv6 RFC. Well, it was reasonable value.
40                                  */
41 #define FL_MAX_LINGER   60      /* Maximal linger timeout */
42
43 /* FL hash table */
44
45 #define FL_MAX_PER_SOCK 32
46 #define FL_MAX_SIZE     4096
47 #define FL_HASH_MASK    255
48 #define FL_HASH(l)      (ntohl(l)&FL_HASH_MASK)
49
50 static atomic_t fl_size = ATOMIC_INIT(0);
51 static struct ip6_flowlabel *fl_ht[FL_HASH_MASK+1];
52
53 static void ip6_fl_gc(unsigned long dummy);
54 static DEFINE_TIMER(ip6_fl_gc_timer, ip6_fl_gc, 0, 0);
55
56 /* FL hash table lock: it protects only of GC */
57
58 static DEFINE_RWLOCK(ip6_fl_lock);
59
60 /* Big socket sock */
61
62 static DEFINE_RWLOCK(ip6_sk_fl_lock);
63
64
65 static inline struct ip6_flowlabel *__fl_lookup(struct net *net, __be32 label)
66 {
67         struct ip6_flowlabel *fl;
68
69         for (fl=fl_ht[FL_HASH(label)]; fl; fl = fl->next) {
70                 if (fl->label == label && fl->fl_net == net)
71                         return fl;
72         }
73         return NULL;
74 }
75
76 static struct ip6_flowlabel *fl_lookup(struct net *net, __be32 label)
77 {
78         struct ip6_flowlabel *fl;
79
80         read_lock_bh(&ip6_fl_lock);
81         fl = __fl_lookup(net, label);
82         if (fl)
83                 atomic_inc(&fl->users);
84         read_unlock_bh(&ip6_fl_lock);
85         return fl;
86 }
87
88
89 static void fl_free(struct ip6_flowlabel *fl)
90 {
91         if (fl) {
92                 release_net(fl->fl_net);
93                 kfree(fl->opt);
94         }
95         kfree(fl);
96 }
97
98 static void fl_release(struct ip6_flowlabel *fl)
99 {
100         write_lock_bh(&ip6_fl_lock);
101
102         fl->lastuse = jiffies;
103         if (atomic_dec_and_test(&fl->users)) {
104                 unsigned long ttd = fl->lastuse + fl->linger;
105                 if (time_after(ttd, fl->expires))
106                         fl->expires = ttd;
107                 ttd = fl->expires;
108                 if (fl->opt && fl->share == IPV6_FL_S_EXCL) {
109                         struct ipv6_txoptions *opt = fl->opt;
110                         fl->opt = NULL;
111                         kfree(opt);
112                 }
113                 if (!timer_pending(&ip6_fl_gc_timer) ||
114                     time_after(ip6_fl_gc_timer.expires, ttd))
115                         mod_timer(&ip6_fl_gc_timer, ttd);
116         }
117         write_unlock_bh(&ip6_fl_lock);
118 }
119
120 static void ip6_fl_gc(unsigned long dummy)
121 {
122         int i;
123         unsigned long now = jiffies;
124         unsigned long sched = 0;
125
126         write_lock(&ip6_fl_lock);
127
128         for (i=0; i<=FL_HASH_MASK; i++) {
129                 struct ip6_flowlabel *fl, **flp;
130                 flp = &fl_ht[i];
131                 while ((fl=*flp) != NULL) {
132                         if (atomic_read(&fl->users) == 0) {
133                                 unsigned long ttd = fl->lastuse + fl->linger;
134                                 if (time_after(ttd, fl->expires))
135                                         fl->expires = ttd;
136                                 ttd = fl->expires;
137                                 if (time_after_eq(now, ttd)) {
138                                         *flp = fl->next;
139                                         fl_free(fl);
140                                         atomic_dec(&fl_size);
141                                         continue;
142                                 }
143                                 if (!sched || time_before(ttd, sched))
144                                         sched = ttd;
145                         }
146                         flp = &fl->next;
147                 }
148         }
149         if (!sched && atomic_read(&fl_size))
150                 sched = now + FL_MAX_LINGER;
151         if (sched) {
152                 mod_timer(&ip6_fl_gc_timer, sched);
153         }
154         write_unlock(&ip6_fl_lock);
155 }
156
157 static void ip6_fl_purge(struct net *net)
158 {
159         int i;
160
161         write_lock(&ip6_fl_lock);
162         for (i = 0; i <= FL_HASH_MASK; i++) {
163                 struct ip6_flowlabel *fl, **flp;
164                 flp = &fl_ht[i];
165                 while ((fl = *flp) != NULL) {
166                         if (fl->fl_net == net && atomic_read(&fl->users) == 0) {
167                                 *flp = fl->next;
168                                 fl_free(fl);
169                                 atomic_dec(&fl_size);
170                                 continue;
171                         }
172                         flp = &fl->next;
173                 }
174         }
175         write_unlock(&ip6_fl_lock);
176 }
177
178 static struct ip6_flowlabel *fl_intern(struct net *net,
179                                        struct ip6_flowlabel *fl, __be32 label)
180 {
181         struct ip6_flowlabel *lfl;
182
183         fl->label = label & IPV6_FLOWLABEL_MASK;
184
185         write_lock_bh(&ip6_fl_lock);
186         if (label == 0) {
187                 for (;;) {
188                         fl->label = htonl(net_random())&IPV6_FLOWLABEL_MASK;
189                         if (fl->label) {
190                                 lfl = __fl_lookup(net, fl->label);
191                                 if (lfl == NULL)
192                                         break;
193                         }
194                 }
195         } else {
196                 /*
197                  * we dropper the ip6_fl_lock, so this entry could reappear
198                  * and we need to recheck with it.
199                  *
200                  * OTOH no need to search the active socket first, like it is
201                  * done in ipv6_flowlabel_opt - sock is locked, so new entry
202                  * with the same label can only appear on another sock
203                  */
204                 lfl = __fl_lookup(net, fl->label);
205                 if (lfl != NULL) {
206                         atomic_inc(&lfl->users);
207                         write_unlock_bh(&ip6_fl_lock);
208                         return lfl;
209                 }
210         }
211
212         fl->lastuse = jiffies;
213         fl->next = fl_ht[FL_HASH(fl->label)];
214         fl_ht[FL_HASH(fl->label)] = fl;
215         atomic_inc(&fl_size);
216         write_unlock_bh(&ip6_fl_lock);
217         return NULL;
218 }
219
220
221
222 /* Socket flowlabel lists */
223
224 struct ip6_flowlabel * fl6_sock_lookup(struct sock *sk, __be32 label)
225 {
226         struct ipv6_fl_socklist *sfl;
227         struct ipv6_pinfo *np = inet6_sk(sk);
228
229         label &= IPV6_FLOWLABEL_MASK;
230
231         read_lock_bh(&ip6_sk_fl_lock);
232         for (sfl=np->ipv6_fl_list; sfl; sfl = sfl->next) {
233                 struct ip6_flowlabel *fl = sfl->fl;
234                 if (fl->label == label) {
235                         fl->lastuse = jiffies;
236                         atomic_inc(&fl->users);
237                         read_unlock_bh(&ip6_sk_fl_lock);
238                         return fl;
239                 }
240         }
241         read_unlock_bh(&ip6_sk_fl_lock);
242         return NULL;
243 }
244
245 EXPORT_SYMBOL_GPL(fl6_sock_lookup);
246
247 void fl6_free_socklist(struct sock *sk)
248 {
249         struct ipv6_pinfo *np = inet6_sk(sk);
250         struct ipv6_fl_socklist *sfl;
251
252         while ((sfl = np->ipv6_fl_list) != NULL) {
253                 np->ipv6_fl_list = sfl->next;
254                 fl_release(sfl->fl);
255                 kfree(sfl);
256         }
257 }
258
259 /* Service routines */
260
261
262 /*
263    It is the only difficult place. flowlabel enforces equal headers
264    before and including routing header, however user may supply options
265    following rthdr.
266  */
267
268 struct ipv6_txoptions *fl6_merge_options(struct ipv6_txoptions * opt_space,
269                                          struct ip6_flowlabel * fl,
270                                          struct ipv6_txoptions * fopt)
271 {
272         struct ipv6_txoptions * fl_opt = fl->opt;
273
274         if (fopt == NULL || fopt->opt_flen == 0)
275                 return fl_opt;
276
277         if (fl_opt != NULL) {
278                 opt_space->hopopt = fl_opt->hopopt;
279                 opt_space->dst0opt = fl_opt->dst0opt;
280                 opt_space->srcrt = fl_opt->srcrt;
281                 opt_space->opt_nflen = fl_opt->opt_nflen;
282         } else {
283                 if (fopt->opt_nflen == 0)
284                         return fopt;
285                 opt_space->hopopt = NULL;
286                 opt_space->dst0opt = NULL;
287                 opt_space->srcrt = NULL;
288                 opt_space->opt_nflen = 0;
289         }
290         opt_space->dst1opt = fopt->dst1opt;
291         opt_space->opt_flen = fopt->opt_flen;
292         return opt_space;
293 }
294
295 static unsigned long check_linger(unsigned long ttl)
296 {
297         if (ttl < FL_MIN_LINGER)
298                 return FL_MIN_LINGER*HZ;
299         if (ttl > FL_MAX_LINGER && !capable(CAP_NET_ADMIN))
300                 return 0;
301         return ttl*HZ;
302 }
303
304 static int fl6_renew(struct ip6_flowlabel *fl, unsigned long linger, unsigned long expires)
305 {
306         linger = check_linger(linger);
307         if (!linger)
308                 return -EPERM;
309         expires = check_linger(expires);
310         if (!expires)
311                 return -EPERM;
312         fl->lastuse = jiffies;
313         if (time_before(fl->linger, linger))
314                 fl->linger = linger;
315         if (time_before(expires, fl->linger))
316                 expires = fl->linger;
317         if (time_before(fl->expires, fl->lastuse + expires))
318                 fl->expires = fl->lastuse + expires;
319         return 0;
320 }
321
322 static struct ip6_flowlabel *
323 fl_create(struct net *net, struct in6_flowlabel_req *freq, char __user *optval,
324           int optlen, int *err_p)
325 {
326         struct ip6_flowlabel *fl;
327         int olen;
328         int addr_type;
329         int err;
330
331         err = -ENOMEM;
332         fl = kzalloc(sizeof(*fl), GFP_KERNEL);
333         if (fl == NULL)
334                 goto done;
335
336         olen = optlen - CMSG_ALIGN(sizeof(*freq));
337         if (olen > 0) {
338                 struct msghdr msg;
339                 struct flowi flowi;
340                 int junk;
341
342                 err = -ENOMEM;
343                 fl->opt = kmalloc(sizeof(*fl->opt) + olen, GFP_KERNEL);
344                 if (fl->opt == NULL)
345                         goto done;
346
347                 memset(fl->opt, 0, sizeof(*fl->opt));
348                 fl->opt->tot_len = sizeof(*fl->opt) + olen;
349                 err = -EFAULT;
350                 if (copy_from_user(fl->opt+1, optval+CMSG_ALIGN(sizeof(*freq)), olen))
351                         goto done;
352
353                 msg.msg_controllen = olen;
354                 msg.msg_control = (void*)(fl->opt+1);
355                 flowi.oif = 0;
356
357                 err = datagram_send_ctl(net, &msg, &flowi, fl->opt, &junk, &junk);
358                 if (err)
359                         goto done;
360                 err = -EINVAL;
361                 if (fl->opt->opt_flen)
362                         goto done;
363                 if (fl->opt->opt_nflen == 0) {
364                         kfree(fl->opt);
365                         fl->opt = NULL;
366                 }
367         }
368
369         fl->fl_net = hold_net(net);
370         fl->expires = jiffies;
371         err = fl6_renew(fl, freq->flr_linger, freq->flr_expires);
372         if (err)
373                 goto done;
374         fl->share = freq->flr_share;
375         addr_type = ipv6_addr_type(&freq->flr_dst);
376         if ((addr_type&IPV6_ADDR_MAPPED)
377             || addr_type == IPV6_ADDR_ANY) {
378                 err = -EINVAL;
379                 goto done;
380         }
381         ipv6_addr_copy(&fl->dst, &freq->flr_dst);
382         atomic_set(&fl->users, 1);
383         switch (fl->share) {
384         case IPV6_FL_S_EXCL:
385         case IPV6_FL_S_ANY:
386                 break;
387         case IPV6_FL_S_PROCESS:
388                 fl->owner = current->pid;
389                 break;
390         case IPV6_FL_S_USER:
391                 fl->owner = current->euid;
392                 break;
393         default:
394                 err = -EINVAL;
395                 goto done;
396         }
397         return fl;
398
399 done:
400         fl_free(fl);
401         *err_p = err;
402         return NULL;
403 }
404
405 static int mem_check(struct sock *sk)
406 {
407         struct ipv6_pinfo *np = inet6_sk(sk);
408         struct ipv6_fl_socklist *sfl;
409         int room = FL_MAX_SIZE - atomic_read(&fl_size);
410         int count = 0;
411
412         if (room > FL_MAX_SIZE - FL_MAX_PER_SOCK)
413                 return 0;
414
415         for (sfl = np->ipv6_fl_list; sfl; sfl = sfl->next)
416                 count++;
417
418         if (room <= 0 ||
419             ((count >= FL_MAX_PER_SOCK ||
420              (count > 0 && room < FL_MAX_SIZE/2) || room < FL_MAX_SIZE/4)
421              && !capable(CAP_NET_ADMIN)))
422                 return -ENOBUFS;
423
424         return 0;
425 }
426
427 static int ipv6_hdr_cmp(struct ipv6_opt_hdr *h1, struct ipv6_opt_hdr *h2)
428 {
429         if (h1 == h2)
430                 return 0;
431         if (h1 == NULL || h2 == NULL)
432                 return 1;
433         if (h1->hdrlen != h2->hdrlen)
434                 return 1;
435         return memcmp(h1+1, h2+1, ((h1->hdrlen+1)<<3) - sizeof(*h1));
436 }
437
438 static int ipv6_opt_cmp(struct ipv6_txoptions *o1, struct ipv6_txoptions *o2)
439 {
440         if (o1 == o2)
441                 return 0;
442         if (o1 == NULL || o2 == NULL)
443                 return 1;
444         if (o1->opt_nflen != o2->opt_nflen)
445                 return 1;
446         if (ipv6_hdr_cmp(o1->hopopt, o2->hopopt))
447                 return 1;
448         if (ipv6_hdr_cmp(o1->dst0opt, o2->dst0opt))
449                 return 1;
450         if (ipv6_hdr_cmp((struct ipv6_opt_hdr *)o1->srcrt, (struct ipv6_opt_hdr *)o2->srcrt))
451                 return 1;
452         return 0;
453 }
454
455 static inline void fl_link(struct ipv6_pinfo *np, struct ipv6_fl_socklist *sfl,
456                 struct ip6_flowlabel *fl)
457 {
458         write_lock_bh(&ip6_sk_fl_lock);
459         sfl->fl = fl;
460         sfl->next = np->ipv6_fl_list;
461         np->ipv6_fl_list = sfl;
462         write_unlock_bh(&ip6_sk_fl_lock);
463 }
464
465 int ipv6_flowlabel_opt(struct sock *sk, char __user *optval, int optlen)
466 {
467         int err;
468         struct net *net = sock_net(sk);
469         struct ipv6_pinfo *np = inet6_sk(sk);
470         struct in6_flowlabel_req freq;
471         struct ipv6_fl_socklist *sfl1=NULL;
472         struct ipv6_fl_socklist *sfl, **sflp;
473         struct ip6_flowlabel *fl, *fl1 = NULL;
474
475
476         if (optlen < sizeof(freq))
477                 return -EINVAL;
478
479         if (copy_from_user(&freq, optval, sizeof(freq)))
480                 return -EFAULT;
481
482         switch (freq.flr_action) {
483         case IPV6_FL_A_PUT:
484                 write_lock_bh(&ip6_sk_fl_lock);
485                 for (sflp = &np->ipv6_fl_list; (sfl=*sflp)!=NULL; sflp = &sfl->next) {
486                         if (sfl->fl->label == freq.flr_label) {
487                                 if (freq.flr_label == (np->flow_label&IPV6_FLOWLABEL_MASK))
488                                         np->flow_label &= ~IPV6_FLOWLABEL_MASK;
489                                 *sflp = sfl->next;
490                                 write_unlock_bh(&ip6_sk_fl_lock);
491                                 fl_release(sfl->fl);
492                                 kfree(sfl);
493                                 return 0;
494                         }
495                 }
496                 write_unlock_bh(&ip6_sk_fl_lock);
497                 return -ESRCH;
498
499         case IPV6_FL_A_RENEW:
500                 read_lock_bh(&ip6_sk_fl_lock);
501                 for (sfl = np->ipv6_fl_list; sfl; sfl = sfl->next) {
502                         if (sfl->fl->label == freq.flr_label) {
503                                 err = fl6_renew(sfl->fl, freq.flr_linger, freq.flr_expires);
504                                 read_unlock_bh(&ip6_sk_fl_lock);
505                                 return err;
506                         }
507                 }
508                 read_unlock_bh(&ip6_sk_fl_lock);
509
510                 if (freq.flr_share == IPV6_FL_S_NONE && capable(CAP_NET_ADMIN)) {
511                         fl = fl_lookup(net, freq.flr_label);
512                         if (fl) {
513                                 err = fl6_renew(fl, freq.flr_linger, freq.flr_expires);
514                                 fl_release(fl);
515                                 return err;
516                         }
517                 }
518                 return -ESRCH;
519
520         case IPV6_FL_A_GET:
521                 if (freq.flr_label & ~IPV6_FLOWLABEL_MASK)
522                         return -EINVAL;
523
524                 fl = fl_create(net, &freq, optval, optlen, &err);
525                 if (fl == NULL)
526                         return err;
527                 sfl1 = kmalloc(sizeof(*sfl1), GFP_KERNEL);
528
529                 if (freq.flr_label) {
530                         err = -EEXIST;
531                         read_lock_bh(&ip6_sk_fl_lock);
532                         for (sfl = np->ipv6_fl_list; sfl; sfl = sfl->next) {
533                                 if (sfl->fl->label == freq.flr_label) {
534                                         if (freq.flr_flags&IPV6_FL_F_EXCL) {
535                                                 read_unlock_bh(&ip6_sk_fl_lock);
536                                                 goto done;
537                                         }
538                                         fl1 = sfl->fl;
539                                         atomic_inc(&fl1->users);
540                                         break;
541                                 }
542                         }
543                         read_unlock_bh(&ip6_sk_fl_lock);
544
545                         if (fl1 == NULL)
546                                 fl1 = fl_lookup(net, freq.flr_label);
547                         if (fl1) {
548 recheck:
549                                 err = -EEXIST;
550                                 if (freq.flr_flags&IPV6_FL_F_EXCL)
551                                         goto release;
552                                 err = -EPERM;
553                                 if (fl1->share == IPV6_FL_S_EXCL ||
554                                     fl1->share != fl->share ||
555                                     fl1->owner != fl->owner)
556                                         goto release;
557
558                                 err = -EINVAL;
559                                 if (!ipv6_addr_equal(&fl1->dst, &fl->dst) ||
560                                     ipv6_opt_cmp(fl1->opt, fl->opt))
561                                         goto release;
562
563                                 err = -ENOMEM;
564                                 if (sfl1 == NULL)
565                                         goto release;
566                                 if (fl->linger > fl1->linger)
567                                         fl1->linger = fl->linger;
568                                 if ((long)(fl->expires - fl1->expires) > 0)
569                                         fl1->expires = fl->expires;
570                                 fl_link(np, sfl1, fl1);
571                                 fl_free(fl);
572                                 return 0;
573
574 release:
575                                 fl_release(fl1);
576                                 goto done;
577                         }
578                 }
579                 err = -ENOENT;
580                 if (!(freq.flr_flags&IPV6_FL_F_CREATE))
581                         goto done;
582
583                 err = -ENOMEM;
584                 if (sfl1 == NULL || (err = mem_check(sk)) != 0)
585                         goto done;
586
587                 fl1 = fl_intern(net, fl, freq.flr_label);
588                 if (fl1 != NULL)
589                         goto recheck;
590
591                 if (!freq.flr_label) {
592                         if (copy_to_user(&((struct in6_flowlabel_req __user *) optval)->flr_label,
593                                          &fl->label, sizeof(fl->label))) {
594                                 /* Intentionally ignore fault. */
595                         }
596                 }
597
598                 fl_link(np, sfl1, fl);
599                 return 0;
600
601         default:
602                 return -EINVAL;
603         }
604
605 done:
606         fl_free(fl);
607         kfree(sfl1);
608         return err;
609 }
610
611 #ifdef CONFIG_PROC_FS
612
613 struct ip6fl_iter_state {
614         struct seq_net_private p;
615         int bucket;
616 };
617
618 #define ip6fl_seq_private(seq)  ((struct ip6fl_iter_state *)(seq)->private)
619
620 static struct ip6_flowlabel *ip6fl_get_first(struct seq_file *seq)
621 {
622         struct ip6_flowlabel *fl = NULL;
623         struct ip6fl_iter_state *state = ip6fl_seq_private(seq);
624         struct net *net = seq_file_net(seq);
625
626         for (state->bucket = 0; state->bucket <= FL_HASH_MASK; ++state->bucket) {
627                 fl = fl_ht[state->bucket];
628
629                 while (fl && fl->fl_net != net)
630                         fl = fl->next;
631                 if (fl)
632                         break;
633         }
634         return fl;
635 }
636
637 static struct ip6_flowlabel *ip6fl_get_next(struct seq_file *seq, struct ip6_flowlabel *fl)
638 {
639         struct ip6fl_iter_state *state = ip6fl_seq_private(seq);
640         struct net *net = seq_file_net(seq);
641
642         fl = fl->next;
643 try_again:
644         while (fl && fl->fl_net != net)
645                 fl = fl->next;
646
647         while (!fl) {
648                 if (++state->bucket <= FL_HASH_MASK) {
649                         fl = fl_ht[state->bucket];
650                         goto try_again;
651                 } else
652                         break;
653         }
654         return fl;
655 }
656
657 static struct ip6_flowlabel *ip6fl_get_idx(struct seq_file *seq, loff_t pos)
658 {
659         struct ip6_flowlabel *fl = ip6fl_get_first(seq);
660         if (fl)
661                 while (pos && (fl = ip6fl_get_next(seq, fl)) != NULL)
662                         --pos;
663         return pos ? NULL : fl;
664 }
665
666 static void *ip6fl_seq_start(struct seq_file *seq, loff_t *pos)
667         __acquires(ip6_fl_lock)
668 {
669         read_lock_bh(&ip6_fl_lock);
670         return *pos ? ip6fl_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
671 }
672
673 static void *ip6fl_seq_next(struct seq_file *seq, void *v, loff_t *pos)
674 {
675         struct ip6_flowlabel *fl;
676
677         if (v == SEQ_START_TOKEN)
678                 fl = ip6fl_get_first(seq);
679         else
680                 fl = ip6fl_get_next(seq, v);
681         ++*pos;
682         return fl;
683 }
684
685 static void ip6fl_seq_stop(struct seq_file *seq, void *v)
686         __releases(ip6_fl_lock)
687 {
688         read_unlock_bh(&ip6_fl_lock);
689 }
690
691 static int ip6fl_seq_show(struct seq_file *seq, void *v)
692 {
693         if (v == SEQ_START_TOKEN)
694                 seq_printf(seq, "%-5s %-1s %-6s %-6s %-6s %-8s %-32s %s\n",
695                            "Label", "S", "Owner", "Users", "Linger", "Expires", "Dst", "Opt");
696         else {
697                 struct ip6_flowlabel *fl = v;
698                 seq_printf(seq,
699                            "%05X %-1d %-6d %-6d %-6ld %-8ld " NIP6_SEQFMT " %-4d\n",
700                            (unsigned)ntohl(fl->label),
701                            fl->share,
702                            (unsigned)fl->owner,
703                            atomic_read(&fl->users),
704                            fl->linger/HZ,
705                            (long)(fl->expires - jiffies)/HZ,
706                            NIP6(fl->dst),
707                            fl->opt ? fl->opt->opt_nflen : 0);
708         }
709         return 0;
710 }
711
712 static const struct seq_operations ip6fl_seq_ops = {
713         .start  =       ip6fl_seq_start,
714         .next   =       ip6fl_seq_next,
715         .stop   =       ip6fl_seq_stop,
716         .show   =       ip6fl_seq_show,
717 };
718
719 static int ip6fl_seq_open(struct inode *inode, struct file *file)
720 {
721         return seq_open_net(inode, file, &ip6fl_seq_ops,
722                             sizeof(struct ip6fl_iter_state));
723 }
724
725 static const struct file_operations ip6fl_seq_fops = {
726         .owner          =       THIS_MODULE,
727         .open           =       ip6fl_seq_open,
728         .read           =       seq_read,
729         .llseek         =       seq_lseek,
730         .release        =       seq_release_net,
731 };
732
733 static int ip6_flowlabel_proc_init(struct net *net)
734 {
735         if (!proc_net_fops_create(net, "ip6_flowlabel",
736                                   S_IRUGO, &ip6fl_seq_fops))
737                 return -ENOMEM;
738         return 0;
739 }
740
741 static void ip6_flowlabel_proc_fini(struct net *net)
742 {
743         proc_net_remove(net, "ip6_flowlabel");
744 }
745 #else
746 static inline int ip6_flowlabel_proc_init(struct net *net)
747 {
748         return 0;
749 }
750 static inline void ip6_flowlabel_proc_fini(struct net *net)
751 {
752         return ;
753 }
754 #endif
755
756 static inline void ip6_flowlabel_net_exit(struct net *net)
757 {
758         ip6_fl_purge(net);
759         ip6_flowlabel_proc_fini(net);
760 }
761
762 static struct pernet_operations ip6_flowlabel_net_ops = {
763         .init = ip6_flowlabel_proc_init,
764         .exit = ip6_flowlabel_net_exit,
765 };
766
767 int ip6_flowlabel_init(void)
768 {
769         return register_pernet_subsys(&ip6_flowlabel_net_ops);
770 }
771
772 void ip6_flowlabel_cleanup(void)
773 {
774         del_timer(&ip6_fl_gc_timer);
775         unregister_pernet_subsys(&ip6_flowlabel_net_ops);
776 }