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/in6.h>
19 #include <linux/proc_fs.h>
20 #include <linux/seq_file.h>
21 #include <linux/slab.h>
22 #include <linux/export.h>
23 #include <linux/pid_namespace.h>
24
25 #include <net/net_namespace.h>
26 #include <net/sock.h>
27
28 #include <net/ipv6.h>
29 #include <net/rawv6.h>
30 #include <net/transp_v6.h>
31
32 #include <linux/uaccess.h>
33
34 #define FL_MIN_LINGER 6 /* Minimal linger. It is set to 6sec specified
35 in old IPv6 RFC. Well, it was reasonable value.
36 */
37 #define FL_MAX_LINGER 150 /* Maximal linger timeout */
38
39 /* FL hash table */
40
41 #define FL_MAX_PER_SOCK 32
42 #define FL_MAX_SIZE 4096
43 #define FL_HASH_MASK 255
44 #define FL_HASH(l) (ntohl(l)&FL_HASH_MASK)
45
46 static atomic_t fl_size = ATOMIC_INIT(0);
47 static struct ip6_flowlabel __rcu *fl_ht[FL_HASH_MASK+1];
48
49 static void ip6_fl_gc(unsigned long dummy);
50 static DEFINE_TIMER(ip6_fl_gc_timer, ip6_fl_gc, 0, 0);
51
52 /* FL hash table lock: it protects only of GC */
53
54 static DEFINE_SPINLOCK(ip6_fl_lock);
55
56 /* Big socket sock */
57
58 static DEFINE_SPINLOCK(ip6_sk_fl_lock);
59
60 #define for_each_fl_rcu(hash, fl) \
61 for (fl = rcu_dereference_bh(fl_ht[(hash)]); \
62 fl != NULL; \
63 fl = rcu_dereference_bh(fl->next))
64 #define for_each_fl_continue_rcu(fl) \
65 for (fl = rcu_dereference_bh(fl->next); \
66 fl != NULL; \
67 fl = rcu_dereference_bh(fl->next))
68
69 #define for_each_sk_fl_rcu(np, sfl) \
70 for (sfl = rcu_dereference_bh(np->ipv6_fl_list); \
71 sfl != NULL; \
72 sfl = rcu_dereference_bh(sfl->next))
73
__fl_lookup(struct net * net,__be32 label)74 static inline struct ip6_flowlabel *__fl_lookup(struct net *net, __be32 label)
75 {
76 struct ip6_flowlabel *fl;
77
78 for_each_fl_rcu(FL_HASH(label), fl) {
79 if (fl->label == label && net_eq(fl->fl_net, net))
80 return fl;
81 }
82 return NULL;
83 }
84
fl_lookup(struct net * net,__be32 label)85 static struct ip6_flowlabel *fl_lookup(struct net *net, __be32 label)
86 {
87 struct ip6_flowlabel *fl;
88
89 rcu_read_lock_bh();
90 fl = __fl_lookup(net, label);
91 if (fl && !atomic_inc_not_zero(&fl->users))
92 fl = NULL;
93 rcu_read_unlock_bh();
94 return fl;
95 }
96
fl_free_rcu(struct rcu_head * head)97 static void fl_free_rcu(struct rcu_head *head)
98 {
99 struct ip6_flowlabel *fl = container_of(head, struct ip6_flowlabel, rcu);
100
101 if (fl->share == IPV6_FL_S_PROCESS)
102 put_pid(fl->owner.pid);
103 kfree(fl->opt);
104 kfree(fl);
105 }
106
107
fl_free(struct ip6_flowlabel * fl)108 static void fl_free(struct ip6_flowlabel *fl)
109 {
110 if (fl)
111 call_rcu(&fl->rcu, fl_free_rcu);
112 }
113
fl_release(struct ip6_flowlabel * fl)114 static void fl_release(struct ip6_flowlabel *fl)
115 {
116 spin_lock_bh(&ip6_fl_lock);
117
118 fl->lastuse = jiffies;
119 if (atomic_dec_and_test(&fl->users)) {
120 unsigned long ttd = fl->lastuse + fl->linger;
121 if (time_after(ttd, fl->expires))
122 fl->expires = ttd;
123 ttd = fl->expires;
124 if (fl->opt && fl->share == IPV6_FL_S_EXCL) {
125 struct ipv6_txoptions *opt = fl->opt;
126 fl->opt = NULL;
127 kfree(opt);
128 }
129 if (!timer_pending(&ip6_fl_gc_timer) ||
130 time_after(ip6_fl_gc_timer.expires, ttd))
131 mod_timer(&ip6_fl_gc_timer, ttd);
132 }
133 spin_unlock_bh(&ip6_fl_lock);
134 }
135
ip6_fl_gc(unsigned long dummy)136 static void ip6_fl_gc(unsigned long dummy)
137 {
138 int i;
139 unsigned long now = jiffies;
140 unsigned long sched = 0;
141
142 spin_lock(&ip6_fl_lock);
143
144 for (i = 0; i <= FL_HASH_MASK; i++) {
145 struct ip6_flowlabel *fl;
146 struct ip6_flowlabel __rcu **flp;
147
148 flp = &fl_ht[i];
149 while ((fl = rcu_dereference_protected(*flp,
150 lockdep_is_held(&ip6_fl_lock))) != NULL) {
151 if (atomic_read(&fl->users) == 0) {
152 unsigned long ttd = fl->lastuse + fl->linger;
153 if (time_after(ttd, fl->expires))
154 fl->expires = ttd;
155 ttd = fl->expires;
156 if (time_after_eq(now, ttd)) {
157 *flp = fl->next;
158 fl_free(fl);
159 atomic_dec(&fl_size);
160 continue;
161 }
162 if (!sched || time_before(ttd, sched))
163 sched = ttd;
164 }
165 flp = &fl->next;
166 }
167 }
168 if (!sched && atomic_read(&fl_size))
169 sched = now + FL_MAX_LINGER;
170 if (sched) {
171 mod_timer(&ip6_fl_gc_timer, sched);
172 }
173 spin_unlock(&ip6_fl_lock);
174 }
175
ip6_fl_purge(struct net * net)176 static void __net_exit ip6_fl_purge(struct net *net)
177 {
178 int i;
179
180 spin_lock_bh(&ip6_fl_lock);
181 for (i = 0; i <= FL_HASH_MASK; i++) {
182 struct ip6_flowlabel *fl;
183 struct ip6_flowlabel __rcu **flp;
184
185 flp = &fl_ht[i];
186 while ((fl = rcu_dereference_protected(*flp,
187 lockdep_is_held(&ip6_fl_lock))) != NULL) {
188 if (net_eq(fl->fl_net, net) &&
189 atomic_read(&fl->users) == 0) {
190 *flp = fl->next;
191 fl_free(fl);
192 atomic_dec(&fl_size);
193 continue;
194 }
195 flp = &fl->next;
196 }
197 }
198 spin_unlock_bh(&ip6_fl_lock);
199 }
200
fl_intern(struct net * net,struct ip6_flowlabel * fl,__be32 label)201 static struct ip6_flowlabel *fl_intern(struct net *net,
202 struct ip6_flowlabel *fl, __be32 label)
203 {
204 struct ip6_flowlabel *lfl;
205
206 fl->label = label & IPV6_FLOWLABEL_MASK;
207
208 spin_lock_bh(&ip6_fl_lock);
209 if (label == 0) {
210 for (;;) {
211 fl->label = htonl(prandom_u32())&IPV6_FLOWLABEL_MASK;
212 if (fl->label) {
213 lfl = __fl_lookup(net, fl->label);
214 if (!lfl)
215 break;
216 }
217 }
218 } else {
219 /*
220 * we dropper the ip6_fl_lock, so this entry could reappear
221 * and we need to recheck with it.
222 *
223 * OTOH no need to search the active socket first, like it is
224 * done in ipv6_flowlabel_opt - sock is locked, so new entry
225 * with the same label can only appear on another sock
226 */
227 lfl = __fl_lookup(net, fl->label);
228 if (lfl) {
229 atomic_inc(&lfl->users);
230 spin_unlock_bh(&ip6_fl_lock);
231 return lfl;
232 }
233 }
234
235 fl->lastuse = jiffies;
236 fl->next = fl_ht[FL_HASH(fl->label)];
237 rcu_assign_pointer(fl_ht[FL_HASH(fl->label)], fl);
238 atomic_inc(&fl_size);
239 spin_unlock_bh(&ip6_fl_lock);
240 return NULL;
241 }
242
243
244
245 /* Socket flowlabel lists */
246
fl6_sock_lookup(struct sock * sk,__be32 label)247 struct ip6_flowlabel *fl6_sock_lookup(struct sock *sk, __be32 label)
248 {
249 struct ipv6_fl_socklist *sfl;
250 struct ipv6_pinfo *np = inet6_sk(sk);
251
252 label &= IPV6_FLOWLABEL_MASK;
253
254 rcu_read_lock_bh();
255 for_each_sk_fl_rcu(np, sfl) {
256 struct ip6_flowlabel *fl = sfl->fl;
257
258 if (fl->label == label && atomic_inc_not_zero(&fl->users)) {
259 fl->lastuse = jiffies;
260 rcu_read_unlock_bh();
261 return fl;
262 }
263 }
264 rcu_read_unlock_bh();
265 return NULL;
266 }
267 EXPORT_SYMBOL_GPL(fl6_sock_lookup);
268
fl6_free_socklist(struct sock * sk)269 void fl6_free_socklist(struct sock *sk)
270 {
271 struct ipv6_pinfo *np = inet6_sk(sk);
272 struct ipv6_fl_socklist *sfl;
273
274 if (!rcu_access_pointer(np->ipv6_fl_list))
275 return;
276
277 spin_lock_bh(&ip6_sk_fl_lock);
278 while ((sfl = rcu_dereference_protected(np->ipv6_fl_list,
279 lockdep_is_held(&ip6_sk_fl_lock))) != NULL) {
280 np->ipv6_fl_list = sfl->next;
281 spin_unlock_bh(&ip6_sk_fl_lock);
282
283 fl_release(sfl->fl);
284 kfree_rcu(sfl, rcu);
285
286 spin_lock_bh(&ip6_sk_fl_lock);
287 }
288 spin_unlock_bh(&ip6_sk_fl_lock);
289 }
290
291 /* Service routines */
292
293
294 /*
295 It is the only difficult place. flowlabel enforces equal headers
296 before and including routing header, however user may supply options
297 following rthdr.
298 */
299
fl6_merge_options(struct ipv6_txoptions * opt_space,struct ip6_flowlabel * fl,struct ipv6_txoptions * fopt)300 struct ipv6_txoptions *fl6_merge_options(struct ipv6_txoptions *opt_space,
301 struct ip6_flowlabel *fl,
302 struct ipv6_txoptions *fopt)
303 {
304 struct ipv6_txoptions *fl_opt = fl->opt;
305
306 if (!fopt || fopt->opt_flen == 0)
307 return fl_opt;
308
309 if (fl_opt) {
310 opt_space->hopopt = fl_opt->hopopt;
311 opt_space->dst0opt = fl_opt->dst0opt;
312 opt_space->srcrt = fl_opt->srcrt;
313 opt_space->opt_nflen = fl_opt->opt_nflen;
314 } else {
315 if (fopt->opt_nflen == 0)
316 return fopt;
317 opt_space->hopopt = NULL;
318 opt_space->dst0opt = NULL;
319 opt_space->srcrt = NULL;
320 opt_space->opt_nflen = 0;
321 }
322 opt_space->dst1opt = fopt->dst1opt;
323 opt_space->opt_flen = fopt->opt_flen;
324 opt_space->tot_len = fopt->tot_len;
325 return opt_space;
326 }
327 EXPORT_SYMBOL_GPL(fl6_merge_options);
328
check_linger(unsigned long ttl)329 static unsigned long check_linger(unsigned long ttl)
330 {
331 if (ttl < FL_MIN_LINGER)
332 return FL_MIN_LINGER*HZ;
333 if (ttl > FL_MAX_LINGER && !capable(CAP_NET_ADMIN))
334 return 0;
335 return ttl*HZ;
336 }
337
fl6_renew(struct ip6_flowlabel * fl,unsigned long linger,unsigned long expires)338 static int fl6_renew(struct ip6_flowlabel *fl, unsigned long linger, unsigned long expires)
339 {
340 linger = check_linger(linger);
341 if (!linger)
342 return -EPERM;
343 expires = check_linger(expires);
344 if (!expires)
345 return -EPERM;
346
347 spin_lock_bh(&ip6_fl_lock);
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 spin_unlock_bh(&ip6_fl_lock);
356
357 return 0;
358 }
359
360 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)361 fl_create(struct net *net, struct sock *sk, struct in6_flowlabel_req *freq,
362 char __user *optval, int optlen, int *err_p)
363 {
364 struct ip6_flowlabel *fl = NULL;
365 int olen;
366 int addr_type;
367 int err;
368
369 olen = optlen - CMSG_ALIGN(sizeof(*freq));
370 err = -EINVAL;
371 if (olen > 64 * 1024)
372 goto done;
373
374 err = -ENOMEM;
375 fl = kzalloc(sizeof(*fl), GFP_KERNEL);
376 if (!fl)
377 goto done;
378
379 if (olen > 0) {
380 struct msghdr msg;
381 struct flowi6 flowi6;
382 struct sockcm_cookie sockc_junk;
383 struct ipcm6_cookie ipc6;
384
385 err = -ENOMEM;
386 fl->opt = kmalloc(sizeof(*fl->opt) + olen, GFP_KERNEL);
387 if (!fl->opt)
388 goto done;
389
390 memset(fl->opt, 0, sizeof(*fl->opt));
391 fl->opt->tot_len = sizeof(*fl->opt) + olen;
392 err = -EFAULT;
393 if (copy_from_user(fl->opt+1, optval+CMSG_ALIGN(sizeof(*freq)), olen))
394 goto done;
395
396 msg.msg_controllen = olen;
397 msg.msg_control = (void *)(fl->opt+1);
398 memset(&flowi6, 0, sizeof(flowi6));
399
400 ipc6.opt = fl->opt;
401 err = ip6_datagram_send_ctl(net, sk, &msg, &flowi6, &ipc6, &sockc_junk);
402 if (err)
403 goto done;
404 err = -EINVAL;
405 if (fl->opt->opt_flen)
406 goto done;
407 if (fl->opt->opt_nflen == 0) {
408 kfree(fl->opt);
409 fl->opt = NULL;
410 }
411 }
412
413 fl->fl_net = net;
414 fl->expires = jiffies;
415 err = fl6_renew(fl, freq->flr_linger, freq->flr_expires);
416 if (err)
417 goto done;
418 fl->share = freq->flr_share;
419 addr_type = ipv6_addr_type(&freq->flr_dst);
420 if ((addr_type & IPV6_ADDR_MAPPED) ||
421 addr_type == IPV6_ADDR_ANY) {
422 err = -EINVAL;
423 goto done;
424 }
425 fl->dst = freq->flr_dst;
426 atomic_set(&fl->users, 1);
427 switch (fl->share) {
428 case IPV6_FL_S_EXCL:
429 case IPV6_FL_S_ANY:
430 break;
431 case IPV6_FL_S_PROCESS:
432 fl->owner.pid = get_task_pid(current, PIDTYPE_PID);
433 break;
434 case IPV6_FL_S_USER:
435 fl->owner.uid = current_euid();
436 break;
437 default:
438 err = -EINVAL;
439 goto done;
440 }
441 return fl;
442
443 done:
444 fl_free(fl);
445 *err_p = err;
446 return NULL;
447 }
448
mem_check(struct sock * sk)449 static int mem_check(struct sock *sk)
450 {
451 struct ipv6_pinfo *np = inet6_sk(sk);
452 struct ipv6_fl_socklist *sfl;
453 int room = FL_MAX_SIZE - atomic_read(&fl_size);
454 int count = 0;
455
456 if (room > FL_MAX_SIZE - FL_MAX_PER_SOCK)
457 return 0;
458
459 rcu_read_lock_bh();
460 for_each_sk_fl_rcu(np, sfl)
461 count++;
462 rcu_read_unlock_bh();
463
464 if (room <= 0 ||
465 ((count >= FL_MAX_PER_SOCK ||
466 (count > 0 && room < FL_MAX_SIZE/2) || room < FL_MAX_SIZE/4) &&
467 !capable(CAP_NET_ADMIN)))
468 return -ENOBUFS;
469
470 return 0;
471 }
472
fl_link(struct ipv6_pinfo * np,struct ipv6_fl_socklist * sfl,struct ip6_flowlabel * fl)473 static inline void fl_link(struct ipv6_pinfo *np, struct ipv6_fl_socklist *sfl,
474 struct ip6_flowlabel *fl)
475 {
476 spin_lock_bh(&ip6_sk_fl_lock);
477 sfl->fl = fl;
478 sfl->next = np->ipv6_fl_list;
479 rcu_assign_pointer(np->ipv6_fl_list, sfl);
480 spin_unlock_bh(&ip6_sk_fl_lock);
481 }
482
ipv6_flowlabel_opt_get(struct sock * sk,struct in6_flowlabel_req * freq,int flags)483 int ipv6_flowlabel_opt_get(struct sock *sk, struct in6_flowlabel_req *freq,
484 int flags)
485 {
486 struct ipv6_pinfo *np = inet6_sk(sk);
487 struct ipv6_fl_socklist *sfl;
488
489 if (flags & IPV6_FL_F_REMOTE) {
490 freq->flr_label = np->rcv_flowinfo & IPV6_FLOWLABEL_MASK;
491 return 0;
492 }
493
494 if (np->repflow) {
495 freq->flr_label = np->flow_label;
496 return 0;
497 }
498
499 rcu_read_lock_bh();
500
501 for_each_sk_fl_rcu(np, sfl) {
502 if (sfl->fl->label == (np->flow_label & IPV6_FLOWLABEL_MASK)) {
503 spin_lock_bh(&ip6_fl_lock);
504 freq->flr_label = sfl->fl->label;
505 freq->flr_dst = sfl->fl->dst;
506 freq->flr_share = sfl->fl->share;
507 freq->flr_expires = (sfl->fl->expires - jiffies) / HZ;
508 freq->flr_linger = sfl->fl->linger / HZ;
509
510 spin_unlock_bh(&ip6_fl_lock);
511 rcu_read_unlock_bh();
512 return 0;
513 }
514 }
515 rcu_read_unlock_bh();
516
517 return -ENOENT;
518 }
519
ipv6_flowlabel_opt(struct sock * sk,char __user * optval,int optlen)520 int ipv6_flowlabel_opt(struct sock *sk, char __user *optval, int optlen)
521 {
522 int uninitialized_var(err);
523 struct net *net = sock_net(sk);
524 struct ipv6_pinfo *np = inet6_sk(sk);
525 struct in6_flowlabel_req freq;
526 struct ipv6_fl_socklist *sfl1 = NULL;
527 struct ipv6_fl_socklist *sfl;
528 struct ipv6_fl_socklist __rcu **sflp;
529 struct ip6_flowlabel *fl, *fl1 = NULL;
530
531
532 if (optlen < sizeof(freq))
533 return -EINVAL;
534
535 if (copy_from_user(&freq, optval, sizeof(freq)))
536 return -EFAULT;
537
538 switch (freq.flr_action) {
539 case IPV6_FL_A_PUT:
540 if (freq.flr_flags & IPV6_FL_F_REFLECT) {
541 if (sk->sk_protocol != IPPROTO_TCP)
542 return -ENOPROTOOPT;
543 if (!np->repflow)
544 return -ESRCH;
545 np->flow_label = 0;
546 np->repflow = 0;
547 return 0;
548 }
549 spin_lock_bh(&ip6_sk_fl_lock);
550 for (sflp = &np->ipv6_fl_list;
551 (sfl = rcu_dereference_protected(*sflp,
552 lockdep_is_held(&ip6_sk_fl_lock))) != NULL;
553 sflp = &sfl->next) {
554 if (sfl->fl->label == freq.flr_label) {
555 if (freq.flr_label == (np->flow_label&IPV6_FLOWLABEL_MASK))
556 np->flow_label &= ~IPV6_FLOWLABEL_MASK;
557 *sflp = sfl->next;
558 spin_unlock_bh(&ip6_sk_fl_lock);
559 fl_release(sfl->fl);
560 kfree_rcu(sfl, rcu);
561 return 0;
562 }
563 }
564 spin_unlock_bh(&ip6_sk_fl_lock);
565 return -ESRCH;
566
567 case IPV6_FL_A_RENEW:
568 rcu_read_lock_bh();
569 for_each_sk_fl_rcu(np, sfl) {
570 if (sfl->fl->label == freq.flr_label) {
571 err = fl6_renew(sfl->fl, freq.flr_linger, freq.flr_expires);
572 rcu_read_unlock_bh();
573 return err;
574 }
575 }
576 rcu_read_unlock_bh();
577
578 if (freq.flr_share == IPV6_FL_S_NONE &&
579 ns_capable(net->user_ns, CAP_NET_ADMIN)) {
580 fl = fl_lookup(net, freq.flr_label);
581 if (fl) {
582 err = fl6_renew(fl, freq.flr_linger, freq.flr_expires);
583 fl_release(fl);
584 return err;
585 }
586 }
587 return -ESRCH;
588
589 case IPV6_FL_A_GET:
590 if (freq.flr_flags & IPV6_FL_F_REFLECT) {
591 struct net *net = sock_net(sk);
592 if (net->ipv6.sysctl.flowlabel_consistency) {
593 net_info_ratelimited("Can not set IPV6_FL_F_REFLECT if flowlabel_consistency sysctl is enable\n");
594 return -EPERM;
595 }
596
597 if (sk->sk_protocol != IPPROTO_TCP)
598 return -ENOPROTOOPT;
599
600 np->repflow = 1;
601 return 0;
602 }
603
604 if (freq.flr_label & ~IPV6_FLOWLABEL_MASK)
605 return -EINVAL;
606
607 if (net->ipv6.sysctl.flowlabel_state_ranges &&
608 (freq.flr_label & IPV6_FLOWLABEL_STATELESS_FLAG))
609 return -ERANGE;
610
611 fl = fl_create(net, sk, &freq, optval, optlen, &err);
612 if (!fl)
613 return err;
614 sfl1 = kmalloc(sizeof(*sfl1), GFP_KERNEL);
615
616 if (freq.flr_label) {
617 err = -EEXIST;
618 rcu_read_lock_bh();
619 for_each_sk_fl_rcu(np, sfl) {
620 if (sfl->fl->label == freq.flr_label) {
621 if (freq.flr_flags&IPV6_FL_F_EXCL) {
622 rcu_read_unlock_bh();
623 goto done;
624 }
625 fl1 = sfl->fl;
626 if (!atomic_inc_not_zero(&fl1->users))
627 fl1 = NULL;
628 break;
629 }
630 }
631 rcu_read_unlock_bh();
632
633 if (!fl1)
634 fl1 = fl_lookup(net, freq.flr_label);
635 if (fl1) {
636 recheck:
637 err = -EEXIST;
638 if (freq.flr_flags&IPV6_FL_F_EXCL)
639 goto release;
640 err = -EPERM;
641 if (fl1->share == IPV6_FL_S_EXCL ||
642 fl1->share != fl->share ||
643 ((fl1->share == IPV6_FL_S_PROCESS) &&
644 (fl1->owner.pid != fl->owner.pid)) ||
645 ((fl1->share == IPV6_FL_S_USER) &&
646 !uid_eq(fl1->owner.uid, fl->owner.uid)))
647 goto release;
648
649 err = -ENOMEM;
650 if (!sfl1)
651 goto release;
652 if (fl->linger > fl1->linger)
653 fl1->linger = fl->linger;
654 if ((long)(fl->expires - fl1->expires) > 0)
655 fl1->expires = fl->expires;
656 fl_link(np, sfl1, fl1);
657 fl_free(fl);
658 return 0;
659
660 release:
661 fl_release(fl1);
662 goto done;
663 }
664 }
665 err = -ENOENT;
666 if (!(freq.flr_flags&IPV6_FL_F_CREATE))
667 goto done;
668
669 err = -ENOMEM;
670 if (!sfl1)
671 goto done;
672
673 err = mem_check(sk);
674 if (err != 0)
675 goto done;
676
677 fl1 = fl_intern(net, fl, freq.flr_label);
678 if (fl1)
679 goto recheck;
680
681 if (!freq.flr_label) {
682 if (copy_to_user(&((struct in6_flowlabel_req __user *) optval)->flr_label,
683 &fl->label, sizeof(fl->label))) {
684 /* Intentionally ignore fault. */
685 }
686 }
687
688 fl_link(np, sfl1, fl);
689 return 0;
690
691 default:
692 return -EINVAL;
693 }
694
695 done:
696 fl_free(fl);
697 kfree(sfl1);
698 return err;
699 }
700
701 #ifdef CONFIG_PROC_FS
702
703 struct ip6fl_iter_state {
704 struct seq_net_private p;
705 struct pid_namespace *pid_ns;
706 int bucket;
707 };
708
709 #define ip6fl_seq_private(seq) ((struct ip6fl_iter_state *)(seq)->private)
710
ip6fl_get_first(struct seq_file * seq)711 static struct ip6_flowlabel *ip6fl_get_first(struct seq_file *seq)
712 {
713 struct ip6_flowlabel *fl = NULL;
714 struct ip6fl_iter_state *state = ip6fl_seq_private(seq);
715 struct net *net = seq_file_net(seq);
716
717 for (state->bucket = 0; state->bucket <= FL_HASH_MASK; ++state->bucket) {
718 for_each_fl_rcu(state->bucket, fl) {
719 if (net_eq(fl->fl_net, net))
720 goto out;
721 }
722 }
723 fl = NULL;
724 out:
725 return fl;
726 }
727
ip6fl_get_next(struct seq_file * seq,struct ip6_flowlabel * fl)728 static struct ip6_flowlabel *ip6fl_get_next(struct seq_file *seq, struct ip6_flowlabel *fl)
729 {
730 struct ip6fl_iter_state *state = ip6fl_seq_private(seq);
731 struct net *net = seq_file_net(seq);
732
733 for_each_fl_continue_rcu(fl) {
734 if (net_eq(fl->fl_net, net))
735 goto out;
736 }
737
738 try_again:
739 if (++state->bucket <= FL_HASH_MASK) {
740 for_each_fl_rcu(state->bucket, fl) {
741 if (net_eq(fl->fl_net, net))
742 goto out;
743 }
744 goto try_again;
745 }
746 fl = NULL;
747
748 out:
749 return fl;
750 }
751
ip6fl_get_idx(struct seq_file * seq,loff_t pos)752 static struct ip6_flowlabel *ip6fl_get_idx(struct seq_file *seq, loff_t pos)
753 {
754 struct ip6_flowlabel *fl = ip6fl_get_first(seq);
755 if (fl)
756 while (pos && (fl = ip6fl_get_next(seq, fl)) != NULL)
757 --pos;
758 return pos ? NULL : fl;
759 }
760
ip6fl_seq_start(struct seq_file * seq,loff_t * pos)761 static void *ip6fl_seq_start(struct seq_file *seq, loff_t *pos)
762 __acquires(RCU)
763 {
764 rcu_read_lock_bh();
765 return *pos ? ip6fl_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
766 }
767
ip6fl_seq_next(struct seq_file * seq,void * v,loff_t * pos)768 static void *ip6fl_seq_next(struct seq_file *seq, void *v, loff_t *pos)
769 {
770 struct ip6_flowlabel *fl;
771
772 if (v == SEQ_START_TOKEN)
773 fl = ip6fl_get_first(seq);
774 else
775 fl = ip6fl_get_next(seq, v);
776 ++*pos;
777 return fl;
778 }
779
ip6fl_seq_stop(struct seq_file * seq,void * v)780 static void ip6fl_seq_stop(struct seq_file *seq, void *v)
781 __releases(RCU)
782 {
783 rcu_read_unlock_bh();
784 }
785
ip6fl_seq_show(struct seq_file * seq,void * v)786 static int ip6fl_seq_show(struct seq_file *seq, void *v)
787 {
788 struct ip6fl_iter_state *state = ip6fl_seq_private(seq);
789 if (v == SEQ_START_TOKEN) {
790 seq_puts(seq, "Label S Owner Users Linger Expires Dst Opt\n");
791 } else {
792 struct ip6_flowlabel *fl = v;
793 seq_printf(seq,
794 "%05X %-1d %-6d %-6d %-6ld %-8ld %pi6 %-4d\n",
795 (unsigned int)ntohl(fl->label),
796 fl->share,
797 ((fl->share == IPV6_FL_S_PROCESS) ?
798 pid_nr_ns(fl->owner.pid, state->pid_ns) :
799 ((fl->share == IPV6_FL_S_USER) ?
800 from_kuid_munged(seq_user_ns(seq), fl->owner.uid) :
801 0)),
802 atomic_read(&fl->users),
803 fl->linger/HZ,
804 (long)(fl->expires - jiffies)/HZ,
805 &fl->dst,
806 fl->opt ? fl->opt->opt_nflen : 0);
807 }
808 return 0;
809 }
810
811 static const struct seq_operations ip6fl_seq_ops = {
812 .start = ip6fl_seq_start,
813 .next = ip6fl_seq_next,
814 .stop = ip6fl_seq_stop,
815 .show = ip6fl_seq_show,
816 };
817
ip6fl_seq_open(struct inode * inode,struct file * file)818 static int ip6fl_seq_open(struct inode *inode, struct file *file)
819 {
820 struct seq_file *seq;
821 struct ip6fl_iter_state *state;
822 int err;
823
824 err = seq_open_net(inode, file, &ip6fl_seq_ops,
825 sizeof(struct ip6fl_iter_state));
826
827 if (!err) {
828 seq = file->private_data;
829 state = ip6fl_seq_private(seq);
830 rcu_read_lock();
831 state->pid_ns = get_pid_ns(task_active_pid_ns(current));
832 rcu_read_unlock();
833 }
834 return err;
835 }
836
ip6fl_seq_release(struct inode * inode,struct file * file)837 static int ip6fl_seq_release(struct inode *inode, struct file *file)
838 {
839 struct seq_file *seq = file->private_data;
840 struct ip6fl_iter_state *state = ip6fl_seq_private(seq);
841 put_pid_ns(state->pid_ns);
842 return seq_release_net(inode, file);
843 }
844
845 static const struct file_operations ip6fl_seq_fops = {
846 .owner = THIS_MODULE,
847 .open = ip6fl_seq_open,
848 .read = seq_read,
849 .llseek = seq_lseek,
850 .release = ip6fl_seq_release,
851 };
852
ip6_flowlabel_proc_init(struct net * net)853 static int __net_init ip6_flowlabel_proc_init(struct net *net)
854 {
855 if (!proc_create("ip6_flowlabel", S_IRUGO, net->proc_net,
856 &ip6fl_seq_fops))
857 return -ENOMEM;
858 return 0;
859 }
860
ip6_flowlabel_proc_fini(struct net * net)861 static void __net_exit ip6_flowlabel_proc_fini(struct net *net)
862 {
863 remove_proc_entry("ip6_flowlabel", net->proc_net);
864 }
865 #else
ip6_flowlabel_proc_init(struct net * net)866 static inline int ip6_flowlabel_proc_init(struct net *net)
867 {
868 return 0;
869 }
ip6_flowlabel_proc_fini(struct net * net)870 static inline void ip6_flowlabel_proc_fini(struct net *net)
871 {
872 }
873 #endif
874
ip6_flowlabel_net_exit(struct net * net)875 static void __net_exit ip6_flowlabel_net_exit(struct net *net)
876 {
877 ip6_fl_purge(net);
878 ip6_flowlabel_proc_fini(net);
879 }
880
881 static struct pernet_operations ip6_flowlabel_net_ops = {
882 .init = ip6_flowlabel_proc_init,
883 .exit = ip6_flowlabel_net_exit,
884 };
885
ip6_flowlabel_init(void)886 int ip6_flowlabel_init(void)
887 {
888 return register_pernet_subsys(&ip6_flowlabel_net_ops);
889 }
890
ip6_flowlabel_cleanup(void)891 void ip6_flowlabel_cleanup(void)
892 {
893 del_timer(&ip6_fl_gc_timer);
894 unregister_pernet_subsys(&ip6_flowlabel_net_ops);
895 }
896