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 <asm/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 int junk;
383
384 err = -ENOMEM;
385 fl->opt = kmalloc(sizeof(*fl->opt) + olen, GFP_KERNEL);
386 if (!fl->opt)
387 goto done;
388
389 memset(fl->opt, 0, sizeof(*fl->opt));
390 fl->opt->tot_len = sizeof(*fl->opt) + olen;
391 err = -EFAULT;
392 if (copy_from_user(fl->opt+1, optval+CMSG_ALIGN(sizeof(*freq)), olen))
393 goto done;
394
395 msg.msg_controllen = olen;
396 msg.msg_control = (void *)(fl->opt+1);
397 memset(&flowi6, 0, sizeof(flowi6));
398
399 err = ip6_datagram_send_ctl(net, sk, &msg, &flowi6, fl->opt,
400 &junk, &junk, &junk);
401 if (err)
402 goto done;
403 err = -EINVAL;
404 if (fl->opt->opt_flen)
405 goto done;
406 if (fl->opt->opt_nflen == 0) {
407 kfree(fl->opt);
408 fl->opt = NULL;
409 }
410 }
411
412 fl->fl_net = net;
413 fl->expires = jiffies;
414 err = fl6_renew(fl, freq->flr_linger, freq->flr_expires);
415 if (err)
416 goto done;
417 fl->share = freq->flr_share;
418 addr_type = ipv6_addr_type(&freq->flr_dst);
419 if ((addr_type & IPV6_ADDR_MAPPED) ||
420 addr_type == IPV6_ADDR_ANY) {
421 err = -EINVAL;
422 goto done;
423 }
424 fl->dst = freq->flr_dst;
425 atomic_set(&fl->users, 1);
426 switch (fl->share) {
427 case IPV6_FL_S_EXCL:
428 case IPV6_FL_S_ANY:
429 break;
430 case IPV6_FL_S_PROCESS:
431 fl->owner.pid = get_task_pid(current, PIDTYPE_PID);
432 break;
433 case IPV6_FL_S_USER:
434 fl->owner.uid = current_euid();
435 break;
436 default:
437 err = -EINVAL;
438 goto done;
439 }
440 return fl;
441
442 done:
443 fl_free(fl);
444 *err_p = err;
445 return NULL;
446 }
447
mem_check(struct sock * sk)448 static int mem_check(struct sock *sk)
449 {
450 struct ipv6_pinfo *np = inet6_sk(sk);
451 struct ipv6_fl_socklist *sfl;
452 int room = FL_MAX_SIZE - atomic_read(&fl_size);
453 int count = 0;
454
455 if (room > FL_MAX_SIZE - FL_MAX_PER_SOCK)
456 return 0;
457
458 rcu_read_lock_bh();
459 for_each_sk_fl_rcu(np, sfl)
460 count++;
461 rcu_read_unlock_bh();
462
463 if (room <= 0 ||
464 ((count >= FL_MAX_PER_SOCK ||
465 (count > 0 && room < FL_MAX_SIZE/2) || room < FL_MAX_SIZE/4) &&
466 !capable(CAP_NET_ADMIN)))
467 return -ENOBUFS;
468
469 return 0;
470 }
471
fl_link(struct ipv6_pinfo * np,struct ipv6_fl_socklist * sfl,struct ip6_flowlabel * fl)472 static inline void fl_link(struct ipv6_pinfo *np, struct ipv6_fl_socklist *sfl,
473 struct ip6_flowlabel *fl)
474 {
475 spin_lock_bh(&ip6_sk_fl_lock);
476 sfl->fl = fl;
477 sfl->next = np->ipv6_fl_list;
478 rcu_assign_pointer(np->ipv6_fl_list, sfl);
479 spin_unlock_bh(&ip6_sk_fl_lock);
480 }
481
ipv6_flowlabel_opt_get(struct sock * sk,struct in6_flowlabel_req * freq,int flags)482 int ipv6_flowlabel_opt_get(struct sock *sk, struct in6_flowlabel_req *freq,
483 int flags)
484 {
485 struct ipv6_pinfo *np = inet6_sk(sk);
486 struct ipv6_fl_socklist *sfl;
487
488 if (flags & IPV6_FL_F_REMOTE) {
489 freq->flr_label = np->rcv_flowinfo & IPV6_FLOWLABEL_MASK;
490 return 0;
491 }
492
493 if (np->repflow) {
494 freq->flr_label = np->flow_label;
495 return 0;
496 }
497
498 rcu_read_lock_bh();
499
500 for_each_sk_fl_rcu(np, sfl) {
501 if (sfl->fl->label == (np->flow_label & IPV6_FLOWLABEL_MASK)) {
502 spin_lock_bh(&ip6_fl_lock);
503 freq->flr_label = sfl->fl->label;
504 freq->flr_dst = sfl->fl->dst;
505 freq->flr_share = sfl->fl->share;
506 freq->flr_expires = (sfl->fl->expires - jiffies) / HZ;
507 freq->flr_linger = sfl->fl->linger / HZ;
508
509 spin_unlock_bh(&ip6_fl_lock);
510 rcu_read_unlock_bh();
511 return 0;
512 }
513 }
514 rcu_read_unlock_bh();
515
516 return -ENOENT;
517 }
518
ipv6_flowlabel_opt(struct sock * sk,char __user * optval,int optlen)519 int ipv6_flowlabel_opt(struct sock *sk, char __user *optval, int optlen)
520 {
521 int uninitialized_var(err);
522 struct net *net = sock_net(sk);
523 struct ipv6_pinfo *np = inet6_sk(sk);
524 struct in6_flowlabel_req freq;
525 struct ipv6_fl_socklist *sfl1 = NULL;
526 struct ipv6_fl_socklist *sfl;
527 struct ipv6_fl_socklist __rcu **sflp;
528 struct ip6_flowlabel *fl, *fl1 = NULL;
529
530
531 if (optlen < sizeof(freq))
532 return -EINVAL;
533
534 if (copy_from_user(&freq, optval, sizeof(freq)))
535 return -EFAULT;
536
537 switch (freq.flr_action) {
538 case IPV6_FL_A_PUT:
539 if (freq.flr_flags & IPV6_FL_F_REFLECT) {
540 if (sk->sk_protocol != IPPROTO_TCP)
541 return -ENOPROTOOPT;
542 if (!np->repflow)
543 return -ESRCH;
544 np->flow_label = 0;
545 np->repflow = 0;
546 return 0;
547 }
548 spin_lock_bh(&ip6_sk_fl_lock);
549 for (sflp = &np->ipv6_fl_list;
550 (sfl = rcu_dereference_protected(*sflp,
551 lockdep_is_held(&ip6_sk_fl_lock))) != NULL;
552 sflp = &sfl->next) {
553 if (sfl->fl->label == freq.flr_label) {
554 if (freq.flr_label == (np->flow_label&IPV6_FLOWLABEL_MASK))
555 np->flow_label &= ~IPV6_FLOWLABEL_MASK;
556 *sflp = sfl->next;
557 spin_unlock_bh(&ip6_sk_fl_lock);
558 fl_release(sfl->fl);
559 kfree_rcu(sfl, rcu);
560 return 0;
561 }
562 }
563 spin_unlock_bh(&ip6_sk_fl_lock);
564 return -ESRCH;
565
566 case IPV6_FL_A_RENEW:
567 rcu_read_lock_bh();
568 for_each_sk_fl_rcu(np, sfl) {
569 if (sfl->fl->label == freq.flr_label) {
570 err = fl6_renew(sfl->fl, freq.flr_linger, freq.flr_expires);
571 rcu_read_unlock_bh();
572 return err;
573 }
574 }
575 rcu_read_unlock_bh();
576
577 if (freq.flr_share == IPV6_FL_S_NONE &&
578 ns_capable(net->user_ns, CAP_NET_ADMIN)) {
579 fl = fl_lookup(net, freq.flr_label);
580 if (fl) {
581 err = fl6_renew(fl, freq.flr_linger, freq.flr_expires);
582 fl_release(fl);
583 return err;
584 }
585 }
586 return -ESRCH;
587
588 case IPV6_FL_A_GET:
589 if (freq.flr_flags & IPV6_FL_F_REFLECT) {
590 struct net *net = sock_net(sk);
591 if (net->ipv6.sysctl.flowlabel_consistency) {
592 net_info_ratelimited("Can not set IPV6_FL_F_REFLECT if flowlabel_consistency sysctl is enable\n");
593 return -EPERM;
594 }
595
596 if (sk->sk_protocol != IPPROTO_TCP)
597 return -ENOPROTOOPT;
598
599 np->repflow = 1;
600 return 0;
601 }
602
603 if (freq.flr_label & ~IPV6_FLOWLABEL_MASK)
604 return -EINVAL;
605
606 if (net->ipv6.sysctl.flowlabel_state_ranges &&
607 (freq.flr_label & IPV6_FLOWLABEL_STATELESS_FLAG))
608 return -ERANGE;
609
610 fl = fl_create(net, sk, &freq, optval, optlen, &err);
611 if (!fl)
612 return err;
613 sfl1 = kmalloc(sizeof(*sfl1), GFP_KERNEL);
614
615 if (freq.flr_label) {
616 err = -EEXIST;
617 rcu_read_lock_bh();
618 for_each_sk_fl_rcu(np, sfl) {
619 if (sfl->fl->label == freq.flr_label) {
620 if (freq.flr_flags&IPV6_FL_F_EXCL) {
621 rcu_read_unlock_bh();
622 goto done;
623 }
624 fl1 = sfl->fl;
625 if (!atomic_inc_not_zero(&fl1->users))
626 fl1 = NULL;
627 break;
628 }
629 }
630 rcu_read_unlock_bh();
631
632 if (!fl1)
633 fl1 = fl_lookup(net, freq.flr_label);
634 if (fl1) {
635 recheck:
636 err = -EEXIST;
637 if (freq.flr_flags&IPV6_FL_F_EXCL)
638 goto release;
639 err = -EPERM;
640 if (fl1->share == IPV6_FL_S_EXCL ||
641 fl1->share != fl->share ||
642 ((fl1->share == IPV6_FL_S_PROCESS) &&
643 (fl1->owner.pid != fl->owner.pid)) ||
644 ((fl1->share == IPV6_FL_S_USER) &&
645 !uid_eq(fl1->owner.uid, fl->owner.uid)))
646 goto release;
647
648 err = -ENOMEM;
649 if (!sfl1)
650 goto release;
651 if (fl->linger > fl1->linger)
652 fl1->linger = fl->linger;
653 if ((long)(fl->expires - fl1->expires) > 0)
654 fl1->expires = fl->expires;
655 fl_link(np, sfl1, fl1);
656 fl_free(fl);
657 return 0;
658
659 release:
660 fl_release(fl1);
661 goto done;
662 }
663 }
664 err = -ENOENT;
665 if (!(freq.flr_flags&IPV6_FL_F_CREATE))
666 goto done;
667
668 err = -ENOMEM;
669 if (!sfl1)
670 goto done;
671
672 err = mem_check(sk);
673 if (err != 0)
674 goto done;
675
676 fl1 = fl_intern(net, fl, freq.flr_label);
677 if (fl1)
678 goto recheck;
679
680 if (!freq.flr_label) {
681 if (copy_to_user(&((struct in6_flowlabel_req __user *) optval)->flr_label,
682 &fl->label, sizeof(fl->label))) {
683 /* Intentionally ignore fault. */
684 }
685 }
686
687 fl_link(np, sfl1, fl);
688 return 0;
689
690 default:
691 return -EINVAL;
692 }
693
694 done:
695 fl_free(fl);
696 kfree(sfl1);
697 return err;
698 }
699
700 #ifdef CONFIG_PROC_FS
701
702 struct ip6fl_iter_state {
703 struct seq_net_private p;
704 struct pid_namespace *pid_ns;
705 int bucket;
706 };
707
708 #define ip6fl_seq_private(seq) ((struct ip6fl_iter_state *)(seq)->private)
709
ip6fl_get_first(struct seq_file * seq)710 static struct ip6_flowlabel *ip6fl_get_first(struct seq_file *seq)
711 {
712 struct ip6_flowlabel *fl = NULL;
713 struct ip6fl_iter_state *state = ip6fl_seq_private(seq);
714 struct net *net = seq_file_net(seq);
715
716 for (state->bucket = 0; state->bucket <= FL_HASH_MASK; ++state->bucket) {
717 for_each_fl_rcu(state->bucket, fl) {
718 if (net_eq(fl->fl_net, net))
719 goto out;
720 }
721 }
722 fl = NULL;
723 out:
724 return fl;
725 }
726
ip6fl_get_next(struct seq_file * seq,struct ip6_flowlabel * fl)727 static struct ip6_flowlabel *ip6fl_get_next(struct seq_file *seq, struct ip6_flowlabel *fl)
728 {
729 struct ip6fl_iter_state *state = ip6fl_seq_private(seq);
730 struct net *net = seq_file_net(seq);
731
732 for_each_fl_continue_rcu(fl) {
733 if (net_eq(fl->fl_net, net))
734 goto out;
735 }
736
737 try_again:
738 if (++state->bucket <= FL_HASH_MASK) {
739 for_each_fl_rcu(state->bucket, fl) {
740 if (net_eq(fl->fl_net, net))
741 goto out;
742 }
743 goto try_again;
744 }
745 fl = NULL;
746
747 out:
748 return fl;
749 }
750
ip6fl_get_idx(struct seq_file * seq,loff_t pos)751 static struct ip6_flowlabel *ip6fl_get_idx(struct seq_file *seq, loff_t pos)
752 {
753 struct ip6_flowlabel *fl = ip6fl_get_first(seq);
754 if (fl)
755 while (pos && (fl = ip6fl_get_next(seq, fl)) != NULL)
756 --pos;
757 return pos ? NULL : fl;
758 }
759
ip6fl_seq_start(struct seq_file * seq,loff_t * pos)760 static void *ip6fl_seq_start(struct seq_file *seq, loff_t *pos)
761 __acquires(RCU)
762 {
763 rcu_read_lock_bh();
764 return *pos ? ip6fl_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
765 }
766
ip6fl_seq_next(struct seq_file * seq,void * v,loff_t * pos)767 static void *ip6fl_seq_next(struct seq_file *seq, void *v, loff_t *pos)
768 {
769 struct ip6_flowlabel *fl;
770
771 if (v == SEQ_START_TOKEN)
772 fl = ip6fl_get_first(seq);
773 else
774 fl = ip6fl_get_next(seq, v);
775 ++*pos;
776 return fl;
777 }
778
ip6fl_seq_stop(struct seq_file * seq,void * v)779 static void ip6fl_seq_stop(struct seq_file *seq, void *v)
780 __releases(RCU)
781 {
782 rcu_read_unlock_bh();
783 }
784
ip6fl_seq_show(struct seq_file * seq,void * v)785 static int ip6fl_seq_show(struct seq_file *seq, void *v)
786 {
787 struct ip6fl_iter_state *state = ip6fl_seq_private(seq);
788 if (v == SEQ_START_TOKEN) {
789 seq_puts(seq, "Label S Owner Users Linger Expires Dst Opt\n");
790 } else {
791 struct ip6_flowlabel *fl = v;
792 seq_printf(seq,
793 "%05X %-1d %-6d %-6d %-6ld %-8ld %pi6 %-4d\n",
794 (unsigned int)ntohl(fl->label),
795 fl->share,
796 ((fl->share == IPV6_FL_S_PROCESS) ?
797 pid_nr_ns(fl->owner.pid, state->pid_ns) :
798 ((fl->share == IPV6_FL_S_USER) ?
799 from_kuid_munged(seq_user_ns(seq), fl->owner.uid) :
800 0)),
801 atomic_read(&fl->users),
802 fl->linger/HZ,
803 (long)(fl->expires - jiffies)/HZ,
804 &fl->dst,
805 fl->opt ? fl->opt->opt_nflen : 0);
806 }
807 return 0;
808 }
809
810 static const struct seq_operations ip6fl_seq_ops = {
811 .start = ip6fl_seq_start,
812 .next = ip6fl_seq_next,
813 .stop = ip6fl_seq_stop,
814 .show = ip6fl_seq_show,
815 };
816
ip6fl_seq_open(struct inode * inode,struct file * file)817 static int ip6fl_seq_open(struct inode *inode, struct file *file)
818 {
819 struct seq_file *seq;
820 struct ip6fl_iter_state *state;
821 int err;
822
823 err = seq_open_net(inode, file, &ip6fl_seq_ops,
824 sizeof(struct ip6fl_iter_state));
825
826 if (!err) {
827 seq = file->private_data;
828 state = ip6fl_seq_private(seq);
829 rcu_read_lock();
830 state->pid_ns = get_pid_ns(task_active_pid_ns(current));
831 rcu_read_unlock();
832 }
833 return err;
834 }
835
ip6fl_seq_release(struct inode * inode,struct file * file)836 static int ip6fl_seq_release(struct inode *inode, struct file *file)
837 {
838 struct seq_file *seq = file->private_data;
839 struct ip6fl_iter_state *state = ip6fl_seq_private(seq);
840 put_pid_ns(state->pid_ns);
841 return seq_release_net(inode, file);
842 }
843
844 static const struct file_operations ip6fl_seq_fops = {
845 .owner = THIS_MODULE,
846 .open = ip6fl_seq_open,
847 .read = seq_read,
848 .llseek = seq_lseek,
849 .release = ip6fl_seq_release,
850 };
851
ip6_flowlabel_proc_init(struct net * net)852 static int __net_init ip6_flowlabel_proc_init(struct net *net)
853 {
854 if (!proc_create("ip6_flowlabel", S_IRUGO, net->proc_net,
855 &ip6fl_seq_fops))
856 return -ENOMEM;
857 return 0;
858 }
859
ip6_flowlabel_proc_fini(struct net * net)860 static void __net_exit ip6_flowlabel_proc_fini(struct net *net)
861 {
862 remove_proc_entry("ip6_flowlabel", net->proc_net);
863 }
864 #else
ip6_flowlabel_proc_init(struct net * net)865 static inline int ip6_flowlabel_proc_init(struct net *net)
866 {
867 return 0;
868 }
ip6_flowlabel_proc_fini(struct net * net)869 static inline void ip6_flowlabel_proc_fini(struct net *net)
870 {
871 }
872 #endif
873
ip6_flowlabel_net_exit(struct net * net)874 static void __net_exit ip6_flowlabel_net_exit(struct net *net)
875 {
876 ip6_fl_purge(net);
877 ip6_flowlabel_proc_fini(net);
878 }
879
880 static struct pernet_operations ip6_flowlabel_net_ops = {
881 .init = ip6_flowlabel_proc_init,
882 .exit = ip6_flowlabel_net_exit,
883 };
884
ip6_flowlabel_init(void)885 int ip6_flowlabel_init(void)
886 {
887 return register_pernet_subsys(&ip6_flowlabel_net_ops);
888 }
889
ip6_flowlabel_cleanup(void)890 void ip6_flowlabel_cleanup(void)
891 {
892 del_timer(&ip6_fl_gc_timer);
893 unregister_pernet_subsys(&ip6_flowlabel_net_ops);
894 }
895