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 #include <linux/export.h>
25 #include <linux/pid_namespace.h>
26
27 #include <net/net_namespace.h>
28 #include <net/sock.h>
29
30 #include <net/ipv6.h>
31 #include <net/ndisc.h>
32 #include <net/protocol.h>
33 #include <net/ip6_route.h>
34 #include <net/addrconf.h>
35 #include <net/rawv6.h>
36 #include <net/icmp.h>
37 #include <net/transp_v6.h>
38
39 #include <asm/uaccess.h>
40
41 #define FL_MIN_LINGER 6 /* Minimal linger. It is set to 6sec specified
42 in old IPv6 RFC. Well, it was reasonable value.
43 */
44 #define FL_MAX_LINGER 60 /* Maximal linger timeout */
45
46 /* FL hash table */
47
48 #define FL_MAX_PER_SOCK 32
49 #define FL_MAX_SIZE 4096
50 #define FL_HASH_MASK 255
51 #define FL_HASH(l) (ntohl(l)&FL_HASH_MASK)
52
53 static atomic_t fl_size = ATOMIC_INIT(0);
54 static struct ip6_flowlabel __rcu *fl_ht[FL_HASH_MASK+1];
55
56 static void ip6_fl_gc(unsigned long dummy);
57 static DEFINE_TIMER(ip6_fl_gc_timer, ip6_fl_gc, 0, 0);
58
59 /* FL hash table lock: it protects only of GC */
60
61 static DEFINE_SPINLOCK(ip6_fl_lock);
62
63 /* Big socket sock */
64
65 static DEFINE_SPINLOCK(ip6_sk_fl_lock);
66
67 #define for_each_fl_rcu(hash, fl) \
68 for (fl = rcu_dereference_bh(fl_ht[(hash)]); \
69 fl != NULL; \
70 fl = rcu_dereference_bh(fl->next))
71 #define for_each_fl_continue_rcu(fl) \
72 for (fl = rcu_dereference_bh(fl->next); \
73 fl != NULL; \
74 fl = rcu_dereference_bh(fl->next))
75
76 #define for_each_sk_fl_rcu(np, sfl) \
77 for (sfl = rcu_dereference_bh(np->ipv6_fl_list); \
78 sfl != NULL; \
79 sfl = rcu_dereference_bh(sfl->next))
80
__fl_lookup(struct net * net,__be32 label)81 static inline struct ip6_flowlabel *__fl_lookup(struct net *net, __be32 label)
82 {
83 struct ip6_flowlabel *fl;
84
85 for_each_fl_rcu(FL_HASH(label), fl) {
86 if (fl->label == label && net_eq(fl->fl_net, net))
87 return fl;
88 }
89 return NULL;
90 }
91
fl_lookup(struct net * net,__be32 label)92 static struct ip6_flowlabel *fl_lookup(struct net *net, __be32 label)
93 {
94 struct ip6_flowlabel *fl;
95
96 rcu_read_lock_bh();
97 fl = __fl_lookup(net, label);
98 if (fl && !atomic_inc_not_zero(&fl->users))
99 fl = NULL;
100 rcu_read_unlock_bh();
101 return fl;
102 }
103
104
fl_free(struct ip6_flowlabel * fl)105 static void fl_free(struct ip6_flowlabel *fl)
106 {
107 if (fl) {
108 if (fl->share == IPV6_FL_S_PROCESS)
109 put_pid(fl->owner.pid);
110 release_net(fl->fl_net);
111 kfree(fl->opt);
112 kfree_rcu(fl, rcu);
113 }
114 }
115
fl_release(struct ip6_flowlabel * fl)116 static void fl_release(struct ip6_flowlabel *fl)
117 {
118 spin_lock_bh(&ip6_fl_lock);
119
120 fl->lastuse = jiffies;
121 if (atomic_dec_and_test(&fl->users)) {
122 unsigned long ttd = fl->lastuse + fl->linger;
123 if (time_after(ttd, fl->expires))
124 fl->expires = ttd;
125 ttd = fl->expires;
126 if (fl->opt && fl->share == IPV6_FL_S_EXCL) {
127 struct ipv6_txoptions *opt = fl->opt;
128 fl->opt = NULL;
129 kfree(opt);
130 }
131 if (!timer_pending(&ip6_fl_gc_timer) ||
132 time_after(ip6_fl_gc_timer.expires, ttd))
133 mod_timer(&ip6_fl_gc_timer, ttd);
134 }
135 spin_unlock_bh(&ip6_fl_lock);
136 }
137
ip6_fl_gc(unsigned long dummy)138 static void ip6_fl_gc(unsigned long dummy)
139 {
140 int i;
141 unsigned long now = jiffies;
142 unsigned long sched = 0;
143
144 spin_lock(&ip6_fl_lock);
145
146 for (i=0; i<=FL_HASH_MASK; i++) {
147 struct ip6_flowlabel *fl;
148 struct ip6_flowlabel __rcu **flp;
149
150 flp = &fl_ht[i];
151 while ((fl = rcu_dereference_protected(*flp,
152 lockdep_is_held(&ip6_fl_lock))) != NULL) {
153 if (atomic_read(&fl->users) == 0) {
154 unsigned long ttd = fl->lastuse + fl->linger;
155 if (time_after(ttd, fl->expires))
156 fl->expires = ttd;
157 ttd = fl->expires;
158 if (time_after_eq(now, ttd)) {
159 *flp = fl->next;
160 fl_free(fl);
161 atomic_dec(&fl_size);
162 continue;
163 }
164 if (!sched || time_before(ttd, sched))
165 sched = ttd;
166 }
167 flp = &fl->next;
168 }
169 }
170 if (!sched && atomic_read(&fl_size))
171 sched = now + FL_MAX_LINGER;
172 if (sched) {
173 mod_timer(&ip6_fl_gc_timer, sched);
174 }
175 spin_unlock(&ip6_fl_lock);
176 }
177
ip6_fl_purge(struct net * net)178 static void __net_exit ip6_fl_purge(struct net *net)
179 {
180 int i;
181
182 spin_lock(&ip6_fl_lock);
183 for (i = 0; i <= FL_HASH_MASK; i++) {
184 struct ip6_flowlabel *fl;
185 struct ip6_flowlabel __rcu **flp;
186
187 flp = &fl_ht[i];
188 while ((fl = rcu_dereference_protected(*flp,
189 lockdep_is_held(&ip6_fl_lock))) != NULL) {
190 if (net_eq(fl->fl_net, net) &&
191 atomic_read(&fl->users) == 0) {
192 *flp = fl->next;
193 fl_free(fl);
194 atomic_dec(&fl_size);
195 continue;
196 }
197 flp = &fl->next;
198 }
199 }
200 spin_unlock(&ip6_fl_lock);
201 }
202
fl_intern(struct net * net,struct ip6_flowlabel * fl,__be32 label)203 static struct ip6_flowlabel *fl_intern(struct net *net,
204 struct ip6_flowlabel *fl, __be32 label)
205 {
206 struct ip6_flowlabel *lfl;
207
208 fl->label = label & IPV6_FLOWLABEL_MASK;
209
210 spin_lock_bh(&ip6_fl_lock);
211 if (label == 0) {
212 for (;;) {
213 fl->label = htonl(net_random())&IPV6_FLOWLABEL_MASK;
214 if (fl->label) {
215 lfl = __fl_lookup(net, fl->label);
216 if (lfl == NULL)
217 break;
218 }
219 }
220 } else {
221 /*
222 * we dropper the ip6_fl_lock, so this entry could reappear
223 * and we need to recheck with it.
224 *
225 * OTOH no need to search the active socket first, like it is
226 * done in ipv6_flowlabel_opt - sock is locked, so new entry
227 * with the same label can only appear on another sock
228 */
229 lfl = __fl_lookup(net, fl->label);
230 if (lfl != NULL) {
231 atomic_inc(&lfl->users);
232 spin_unlock_bh(&ip6_fl_lock);
233 return lfl;
234 }
235 }
236
237 fl->lastuse = jiffies;
238 fl->next = fl_ht[FL_HASH(fl->label)];
239 rcu_assign_pointer(fl_ht[FL_HASH(fl->label)], fl);
240 atomic_inc(&fl_size);
241 spin_unlock_bh(&ip6_fl_lock);
242 return NULL;
243 }
244
245
246
247 /* Socket flowlabel lists */
248
fl6_sock_lookup(struct sock * sk,__be32 label)249 struct ip6_flowlabel * fl6_sock_lookup(struct sock *sk, __be32 label)
250 {
251 struct ipv6_fl_socklist *sfl;
252 struct ipv6_pinfo *np = inet6_sk(sk);
253
254 label &= IPV6_FLOWLABEL_MASK;
255
256 rcu_read_lock_bh();
257 for_each_sk_fl_rcu(np, sfl) {
258 struct ip6_flowlabel *fl = sfl->fl;
259 if (fl->label == label) {
260 fl->lastuse = jiffies;
261 atomic_inc(&fl->users);
262 rcu_read_unlock_bh();
263 return fl;
264 }
265 }
266 rcu_read_unlock_bh();
267 return NULL;
268 }
269
270 EXPORT_SYMBOL_GPL(fl6_sock_lookup);
271
fl6_free_socklist(struct sock * sk)272 void fl6_free_socklist(struct sock *sk)
273 {
274 struct ipv6_pinfo *np = inet6_sk(sk);
275 struct ipv6_fl_socklist *sfl;
276
277 if (!rcu_access_pointer(np->ipv6_fl_list))
278 return;
279
280 spin_lock_bh(&ip6_sk_fl_lock);
281 while ((sfl = rcu_dereference_protected(np->ipv6_fl_list,
282 lockdep_is_held(&ip6_sk_fl_lock))) != NULL) {
283 np->ipv6_fl_list = sfl->next;
284 spin_unlock_bh(&ip6_sk_fl_lock);
285
286 fl_release(sfl->fl);
287 kfree_rcu(sfl, rcu);
288
289 spin_lock_bh(&ip6_sk_fl_lock);
290 }
291 spin_unlock_bh(&ip6_sk_fl_lock);
292 }
293
294 /* Service routines */
295
296
297 /*
298 It is the only difficult place. flowlabel enforces equal headers
299 before and including routing header, however user may supply options
300 following rthdr.
301 */
302
fl6_merge_options(struct ipv6_txoptions * opt_space,struct ip6_flowlabel * fl,struct ipv6_txoptions * fopt)303 struct ipv6_txoptions *fl6_merge_options(struct ipv6_txoptions * opt_space,
304 struct ip6_flowlabel * fl,
305 struct ipv6_txoptions * fopt)
306 {
307 struct ipv6_txoptions * fl_opt = fl->opt;
308
309 if (fopt == NULL || fopt->opt_flen == 0)
310 return fl_opt;
311
312 if (fl_opt != NULL) {
313 opt_space->hopopt = fl_opt->hopopt;
314 opt_space->dst0opt = fl_opt->dst0opt;
315 opt_space->srcrt = fl_opt->srcrt;
316 opt_space->opt_nflen = fl_opt->opt_nflen;
317 } else {
318 if (fopt->opt_nflen == 0)
319 return fopt;
320 opt_space->hopopt = NULL;
321 opt_space->dst0opt = NULL;
322 opt_space->srcrt = NULL;
323 opt_space->opt_nflen = 0;
324 }
325 opt_space->dst1opt = fopt->dst1opt;
326 opt_space->opt_flen = fopt->opt_flen;
327 return opt_space;
328 }
329 EXPORT_SYMBOL_GPL(fl6_merge_options);
330
check_linger(unsigned long ttl)331 static unsigned long check_linger(unsigned long ttl)
332 {
333 if (ttl < FL_MIN_LINGER)
334 return FL_MIN_LINGER*HZ;
335 if (ttl > FL_MAX_LINGER && !capable(CAP_NET_ADMIN))
336 return 0;
337 return ttl*HZ;
338 }
339
fl6_renew(struct ip6_flowlabel * fl,unsigned long linger,unsigned long expires)340 static int fl6_renew(struct ip6_flowlabel *fl, unsigned long linger, unsigned long expires)
341 {
342 linger = check_linger(linger);
343 if (!linger)
344 return -EPERM;
345 expires = check_linger(expires);
346 if (!expires)
347 return -EPERM;
348 fl->lastuse = jiffies;
349 if (time_before(fl->linger, linger))
350 fl->linger = linger;
351 if (time_before(expires, fl->linger))
352 expires = fl->linger;
353 if (time_before(fl->expires, fl->lastuse + expires))
354 fl->expires = fl->lastuse + expires;
355 return 0;
356 }
357
358 static struct ip6_flowlabel *
fl_create(struct net * net,struct sock * sk,struct in6_flowlabel_req * freq,char __user * optval,int optlen,int * err_p)359 fl_create(struct net *net, struct sock *sk, struct in6_flowlabel_req *freq,
360 char __user *optval, int optlen, int *err_p)
361 {
362 struct ip6_flowlabel *fl = NULL;
363 int olen;
364 int addr_type;
365 int err;
366
367 olen = optlen - CMSG_ALIGN(sizeof(*freq));
368 err = -EINVAL;
369 if (olen > 64 * 1024)
370 goto done;
371
372 err = -ENOMEM;
373 fl = kzalloc(sizeof(*fl), GFP_KERNEL);
374 if (fl == NULL)
375 goto done;
376
377 if (olen > 0) {
378 struct msghdr msg;
379 struct flowi6 flowi6;
380 int junk;
381
382 err = -ENOMEM;
383 fl->opt = kmalloc(sizeof(*fl->opt) + olen, GFP_KERNEL);
384 if (fl->opt == NULL)
385 goto done;
386
387 memset(fl->opt, 0, sizeof(*fl->opt));
388 fl->opt->tot_len = sizeof(*fl->opt) + olen;
389 err = -EFAULT;
390 if (copy_from_user(fl->opt+1, optval+CMSG_ALIGN(sizeof(*freq)), olen))
391 goto done;
392
393 msg.msg_controllen = olen;
394 msg.msg_control = (void*)(fl->opt+1);
395 memset(&flowi6, 0, sizeof(flowi6));
396
397 err = ip6_datagram_send_ctl(net, sk, &msg, &flowi6, fl->opt,
398 &junk, &junk, &junk);
399 if (err)
400 goto done;
401 err = -EINVAL;
402 if (fl->opt->opt_flen)
403 goto done;
404 if (fl->opt->opt_nflen == 0) {
405 kfree(fl->opt);
406 fl->opt = NULL;
407 }
408 }
409
410 fl->fl_net = hold_net(net);
411 fl->expires = jiffies;
412 err = fl6_renew(fl, freq->flr_linger, freq->flr_expires);
413 if (err)
414 goto done;
415 fl->share = freq->flr_share;
416 addr_type = ipv6_addr_type(&freq->flr_dst);
417 if ((addr_type & IPV6_ADDR_MAPPED) ||
418 addr_type == IPV6_ADDR_ANY) {
419 err = -EINVAL;
420 goto done;
421 }
422 fl->dst = freq->flr_dst;
423 atomic_set(&fl->users, 1);
424 switch (fl->share) {
425 case IPV6_FL_S_EXCL:
426 case IPV6_FL_S_ANY:
427 break;
428 case IPV6_FL_S_PROCESS:
429 fl->owner.pid = get_task_pid(current, PIDTYPE_PID);
430 break;
431 case IPV6_FL_S_USER:
432 fl->owner.uid = current_euid();
433 break;
434 default:
435 err = -EINVAL;
436 goto done;
437 }
438 return fl;
439
440 done:
441 fl_free(fl);
442 *err_p = err;
443 return NULL;
444 }
445
mem_check(struct sock * sk)446 static int mem_check(struct sock *sk)
447 {
448 struct ipv6_pinfo *np = inet6_sk(sk);
449 struct ipv6_fl_socklist *sfl;
450 int room = FL_MAX_SIZE - atomic_read(&fl_size);
451 int count = 0;
452
453 if (room > FL_MAX_SIZE - FL_MAX_PER_SOCK)
454 return 0;
455
456 for_each_sk_fl_rcu(np, sfl)
457 count++;
458
459 if (room <= 0 ||
460 ((count >= FL_MAX_PER_SOCK ||
461 (count > 0 && room < FL_MAX_SIZE/2) || room < FL_MAX_SIZE/4) &&
462 !capable(CAP_NET_ADMIN)))
463 return -ENOBUFS;
464
465 return 0;
466 }
467
ipv6_hdr_cmp(struct ipv6_opt_hdr * h1,struct ipv6_opt_hdr * h2)468 static bool ipv6_hdr_cmp(struct ipv6_opt_hdr *h1, struct ipv6_opt_hdr *h2)
469 {
470 if (h1 == h2)
471 return false;
472 if (h1 == NULL || h2 == NULL)
473 return true;
474 if (h1->hdrlen != h2->hdrlen)
475 return true;
476 return memcmp(h1+1, h2+1, ((h1->hdrlen+1)<<3) - sizeof(*h1));
477 }
478
ipv6_opt_cmp(struct ipv6_txoptions * o1,struct ipv6_txoptions * o2)479 static bool ipv6_opt_cmp(struct ipv6_txoptions *o1, struct ipv6_txoptions *o2)
480 {
481 if (o1 == o2)
482 return false;
483 if (o1 == NULL || o2 == NULL)
484 return true;
485 if (o1->opt_nflen != o2->opt_nflen)
486 return true;
487 if (ipv6_hdr_cmp(o1->hopopt, o2->hopopt))
488 return true;
489 if (ipv6_hdr_cmp(o1->dst0opt, o2->dst0opt))
490 return true;
491 if (ipv6_hdr_cmp((struct ipv6_opt_hdr *)o1->srcrt, (struct ipv6_opt_hdr *)o2->srcrt))
492 return true;
493 return false;
494 }
495
fl_link(struct ipv6_pinfo * np,struct ipv6_fl_socklist * sfl,struct ip6_flowlabel * fl)496 static inline void fl_link(struct ipv6_pinfo *np, struct ipv6_fl_socklist *sfl,
497 struct ip6_flowlabel *fl)
498 {
499 spin_lock_bh(&ip6_sk_fl_lock);
500 sfl->fl = fl;
501 sfl->next = np->ipv6_fl_list;
502 rcu_assign_pointer(np->ipv6_fl_list, sfl);
503 spin_unlock_bh(&ip6_sk_fl_lock);
504 }
505
ipv6_flowlabel_opt(struct sock * sk,char __user * optval,int optlen)506 int ipv6_flowlabel_opt(struct sock *sk, char __user *optval, int optlen)
507 {
508 int uninitialized_var(err);
509 struct net *net = sock_net(sk);
510 struct ipv6_pinfo *np = inet6_sk(sk);
511 struct in6_flowlabel_req freq;
512 struct ipv6_fl_socklist *sfl1=NULL;
513 struct ipv6_fl_socklist *sfl;
514 struct ipv6_fl_socklist __rcu **sflp;
515 struct ip6_flowlabel *fl, *fl1 = NULL;
516
517
518 if (optlen < sizeof(freq))
519 return -EINVAL;
520
521 if (copy_from_user(&freq, optval, sizeof(freq)))
522 return -EFAULT;
523
524 switch (freq.flr_action) {
525 case IPV6_FL_A_PUT:
526 spin_lock_bh(&ip6_sk_fl_lock);
527 for (sflp = &np->ipv6_fl_list;
528 (sfl = rcu_dereference(*sflp))!=NULL;
529 sflp = &sfl->next) {
530 if (sfl->fl->label == freq.flr_label) {
531 if (freq.flr_label == (np->flow_label&IPV6_FLOWLABEL_MASK))
532 np->flow_label &= ~IPV6_FLOWLABEL_MASK;
533 *sflp = rcu_dereference(sfl->next);
534 spin_unlock_bh(&ip6_sk_fl_lock);
535 fl_release(sfl->fl);
536 kfree_rcu(sfl, rcu);
537 return 0;
538 }
539 }
540 spin_unlock_bh(&ip6_sk_fl_lock);
541 return -ESRCH;
542
543 case IPV6_FL_A_RENEW:
544 rcu_read_lock_bh();
545 for_each_sk_fl_rcu(np, sfl) {
546 if (sfl->fl->label == freq.flr_label) {
547 err = fl6_renew(sfl->fl, freq.flr_linger, freq.flr_expires);
548 rcu_read_unlock_bh();
549 return err;
550 }
551 }
552 rcu_read_unlock_bh();
553
554 if (freq.flr_share == IPV6_FL_S_NONE &&
555 ns_capable(net->user_ns, CAP_NET_ADMIN)) {
556 fl = fl_lookup(net, freq.flr_label);
557 if (fl) {
558 err = fl6_renew(fl, freq.flr_linger, freq.flr_expires);
559 fl_release(fl);
560 return err;
561 }
562 }
563 return -ESRCH;
564
565 case IPV6_FL_A_GET:
566 if (freq.flr_label & ~IPV6_FLOWLABEL_MASK)
567 return -EINVAL;
568
569 fl = fl_create(net, sk, &freq, optval, optlen, &err);
570 if (fl == NULL)
571 return err;
572 sfl1 = kmalloc(sizeof(*sfl1), GFP_KERNEL);
573
574 if (freq.flr_label) {
575 err = -EEXIST;
576 rcu_read_lock_bh();
577 for_each_sk_fl_rcu(np, sfl) {
578 if (sfl->fl->label == freq.flr_label) {
579 if (freq.flr_flags&IPV6_FL_F_EXCL) {
580 rcu_read_unlock_bh();
581 goto done;
582 }
583 fl1 = sfl->fl;
584 atomic_inc(&fl1->users);
585 break;
586 }
587 }
588 rcu_read_unlock_bh();
589
590 if (fl1 == NULL)
591 fl1 = fl_lookup(net, freq.flr_label);
592 if (fl1) {
593 recheck:
594 err = -EEXIST;
595 if (freq.flr_flags&IPV6_FL_F_EXCL)
596 goto release;
597 err = -EPERM;
598 if (fl1->share == IPV6_FL_S_EXCL ||
599 fl1->share != fl->share ||
600 ((fl1->share == IPV6_FL_S_PROCESS) &&
601 (fl1->owner.pid == fl->owner.pid)) ||
602 ((fl1->share == IPV6_FL_S_USER) &&
603 uid_eq(fl1->owner.uid, fl->owner.uid)))
604 goto release;
605
606 err = -EINVAL;
607 if (!ipv6_addr_equal(&fl1->dst, &fl->dst) ||
608 ipv6_opt_cmp(fl1->opt, fl->opt))
609 goto release;
610
611 err = -ENOMEM;
612 if (sfl1 == NULL)
613 goto release;
614 if (fl->linger > fl1->linger)
615 fl1->linger = fl->linger;
616 if ((long)(fl->expires - fl1->expires) > 0)
617 fl1->expires = fl->expires;
618 fl_link(np, sfl1, fl1);
619 fl_free(fl);
620 return 0;
621
622 release:
623 fl_release(fl1);
624 goto done;
625 }
626 }
627 err = -ENOENT;
628 if (!(freq.flr_flags&IPV6_FL_F_CREATE))
629 goto done;
630
631 err = -ENOMEM;
632 if (sfl1 == NULL || (err = mem_check(sk)) != 0)
633 goto done;
634
635 fl1 = fl_intern(net, fl, freq.flr_label);
636 if (fl1 != NULL)
637 goto recheck;
638
639 if (!freq.flr_label) {
640 if (copy_to_user(&((struct in6_flowlabel_req __user *) optval)->flr_label,
641 &fl->label, sizeof(fl->label))) {
642 /* Intentionally ignore fault. */
643 }
644 }
645
646 fl_link(np, sfl1, fl);
647 return 0;
648
649 default:
650 return -EINVAL;
651 }
652
653 done:
654 fl_free(fl);
655 kfree(sfl1);
656 return err;
657 }
658
659 #ifdef CONFIG_PROC_FS
660
661 struct ip6fl_iter_state {
662 struct seq_net_private p;
663 struct pid_namespace *pid_ns;
664 int bucket;
665 };
666
667 #define ip6fl_seq_private(seq) ((struct ip6fl_iter_state *)(seq)->private)
668
ip6fl_get_first(struct seq_file * seq)669 static struct ip6_flowlabel *ip6fl_get_first(struct seq_file *seq)
670 {
671 struct ip6_flowlabel *fl = NULL;
672 struct ip6fl_iter_state *state = ip6fl_seq_private(seq);
673 struct net *net = seq_file_net(seq);
674
675 for (state->bucket = 0; state->bucket <= FL_HASH_MASK; ++state->bucket) {
676 for_each_fl_rcu(state->bucket, fl) {
677 if (net_eq(fl->fl_net, net))
678 goto out;
679 }
680 }
681 fl = NULL;
682 out:
683 return fl;
684 }
685
ip6fl_get_next(struct seq_file * seq,struct ip6_flowlabel * fl)686 static struct ip6_flowlabel *ip6fl_get_next(struct seq_file *seq, struct ip6_flowlabel *fl)
687 {
688 struct ip6fl_iter_state *state = ip6fl_seq_private(seq);
689 struct net *net = seq_file_net(seq);
690
691 for_each_fl_continue_rcu(fl) {
692 if (net_eq(fl->fl_net, net))
693 goto out;
694 }
695
696 try_again:
697 if (++state->bucket <= FL_HASH_MASK) {
698 for_each_fl_rcu(state->bucket, fl) {
699 if (net_eq(fl->fl_net, net))
700 goto out;
701 }
702 goto try_again;
703 }
704 fl = NULL;
705
706 out:
707 return fl;
708 }
709
ip6fl_get_idx(struct seq_file * seq,loff_t pos)710 static struct ip6_flowlabel *ip6fl_get_idx(struct seq_file *seq, loff_t pos)
711 {
712 struct ip6_flowlabel *fl = ip6fl_get_first(seq);
713 if (fl)
714 while (pos && (fl = ip6fl_get_next(seq, fl)) != NULL)
715 --pos;
716 return pos ? NULL : fl;
717 }
718
ip6fl_seq_start(struct seq_file * seq,loff_t * pos)719 static void *ip6fl_seq_start(struct seq_file *seq, loff_t *pos)
720 __acquires(RCU)
721 {
722 rcu_read_lock_bh();
723 return *pos ? ip6fl_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
724 }
725
ip6fl_seq_next(struct seq_file * seq,void * v,loff_t * pos)726 static void *ip6fl_seq_next(struct seq_file *seq, void *v, loff_t *pos)
727 {
728 struct ip6_flowlabel *fl;
729
730 if (v == SEQ_START_TOKEN)
731 fl = ip6fl_get_first(seq);
732 else
733 fl = ip6fl_get_next(seq, v);
734 ++*pos;
735 return fl;
736 }
737
ip6fl_seq_stop(struct seq_file * seq,void * v)738 static void ip6fl_seq_stop(struct seq_file *seq, void *v)
739 __releases(RCU)
740 {
741 rcu_read_unlock_bh();
742 }
743
ip6fl_seq_show(struct seq_file * seq,void * v)744 static int ip6fl_seq_show(struct seq_file *seq, void *v)
745 {
746 struct ip6fl_iter_state *state = ip6fl_seq_private(seq);
747 if (v == SEQ_START_TOKEN)
748 seq_printf(seq, "%-5s %-1s %-6s %-6s %-6s %-8s %-32s %s\n",
749 "Label", "S", "Owner", "Users", "Linger", "Expires", "Dst", "Opt");
750 else {
751 struct ip6_flowlabel *fl = v;
752 seq_printf(seq,
753 "%05X %-1d %-6d %-6d %-6ld %-8ld %pi6 %-4d\n",
754 (unsigned int)ntohl(fl->label),
755 fl->share,
756 ((fl->share == IPV6_FL_S_PROCESS) ?
757 pid_nr_ns(fl->owner.pid, state->pid_ns) :
758 ((fl->share == IPV6_FL_S_USER) ?
759 from_kuid_munged(seq_user_ns(seq), fl->owner.uid) :
760 0)),
761 atomic_read(&fl->users),
762 fl->linger/HZ,
763 (long)(fl->expires - jiffies)/HZ,
764 &fl->dst,
765 fl->opt ? fl->opt->opt_nflen : 0);
766 }
767 return 0;
768 }
769
770 static const struct seq_operations ip6fl_seq_ops = {
771 .start = ip6fl_seq_start,
772 .next = ip6fl_seq_next,
773 .stop = ip6fl_seq_stop,
774 .show = ip6fl_seq_show,
775 };
776
ip6fl_seq_open(struct inode * inode,struct file * file)777 static int ip6fl_seq_open(struct inode *inode, struct file *file)
778 {
779 struct seq_file *seq;
780 struct ip6fl_iter_state *state;
781 int err;
782
783 err = seq_open_net(inode, file, &ip6fl_seq_ops,
784 sizeof(struct ip6fl_iter_state));
785
786 if (!err) {
787 seq = file->private_data;
788 state = ip6fl_seq_private(seq);
789 rcu_read_lock();
790 state->pid_ns = get_pid_ns(task_active_pid_ns(current));
791 rcu_read_unlock();
792 }
793 return err;
794 }
795
ip6fl_seq_release(struct inode * inode,struct file * file)796 static int ip6fl_seq_release(struct inode *inode, struct file *file)
797 {
798 struct seq_file *seq = file->private_data;
799 struct ip6fl_iter_state *state = ip6fl_seq_private(seq);
800 put_pid_ns(state->pid_ns);
801 return seq_release_net(inode, file);
802 }
803
804 static const struct file_operations ip6fl_seq_fops = {
805 .owner = THIS_MODULE,
806 .open = ip6fl_seq_open,
807 .read = seq_read,
808 .llseek = seq_lseek,
809 .release = ip6fl_seq_release,
810 };
811
ip6_flowlabel_proc_init(struct net * net)812 static int __net_init ip6_flowlabel_proc_init(struct net *net)
813 {
814 if (!proc_create("ip6_flowlabel", S_IRUGO, net->proc_net,
815 &ip6fl_seq_fops))
816 return -ENOMEM;
817 return 0;
818 }
819
ip6_flowlabel_proc_fini(struct net * net)820 static void __net_exit ip6_flowlabel_proc_fini(struct net *net)
821 {
822 remove_proc_entry("ip6_flowlabel", net->proc_net);
823 }
824 #else
ip6_flowlabel_proc_init(struct net * net)825 static inline int ip6_flowlabel_proc_init(struct net *net)
826 {
827 return 0;
828 }
ip6_flowlabel_proc_fini(struct net * net)829 static inline void ip6_flowlabel_proc_fini(struct net *net)
830 {
831 }
832 #endif
833
ip6_flowlabel_net_exit(struct net * net)834 static void __net_exit ip6_flowlabel_net_exit(struct net *net)
835 {
836 ip6_fl_purge(net);
837 ip6_flowlabel_proc_fini(net);
838 }
839
840 static struct pernet_operations ip6_flowlabel_net_ops = {
841 .init = ip6_flowlabel_proc_init,
842 .exit = ip6_flowlabel_net_exit,
843 };
844
ip6_flowlabel_init(void)845 int ip6_flowlabel_init(void)
846 {
847 return register_pernet_subsys(&ip6_flowlabel_net_ops);
848 }
849
ip6_flowlabel_cleanup(void)850 void ip6_flowlabel_cleanup(void)
851 {
852 del_timer(&ip6_fl_gc_timer);
853 unregister_pernet_subsys(&ip6_flowlabel_net_ops);
854 }
855