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12#include <linux/module.h>
13#include <linux/slab.h>
14#include <linux/types.h>
15#include <linux/kernel.h>
16#include <linux/string.h>
17#include <linux/errno.h>
18#include <linux/skbuff.h>
19#include <net/dst.h>
20#include <net/route.h>
21#include <net/netlink.h>
22#include <net/act_api.h>
23#include <net/pkt_cls.h>
24
25
26
27
28
29
30
31
32struct route4_fastmap {
33 struct route4_filter *filter;
34 u32 id;
35 int iif;
36};
37
38struct route4_head {
39 struct route4_fastmap fastmap[16];
40 struct route4_bucket __rcu *table[256 + 1];
41 struct rcu_head rcu;
42};
43
44struct route4_bucket {
45
46 struct route4_filter __rcu *ht[16 + 16 + 1];
47 struct rcu_head rcu;
48};
49
50struct route4_filter {
51 struct route4_filter __rcu *next;
52 u32 id;
53 int iif;
54
55 struct tcf_result res;
56 struct tcf_exts exts;
57 u32 handle;
58 struct route4_bucket *bkt;
59 struct tcf_proto *tp;
60 union {
61 struct work_struct work;
62 struct rcu_head rcu;
63 };
64};
65
66#define ROUTE4_FAILURE ((struct route4_filter *)(-1L))
67
68static inline int route4_fastmap_hash(u32 id, int iif)
69{
70 return id & 0xF;
71}
72
73static DEFINE_SPINLOCK(fastmap_lock);
74static void
75route4_reset_fastmap(struct route4_head *head)
76{
77 spin_lock_bh(&fastmap_lock);
78 memset(head->fastmap, 0, sizeof(head->fastmap));
79 spin_unlock_bh(&fastmap_lock);
80}
81
82static void
83route4_set_fastmap(struct route4_head *head, u32 id, int iif,
84 struct route4_filter *f)
85{
86 int h = route4_fastmap_hash(id, iif);
87
88
89 spin_lock_bh(&fastmap_lock);
90 head->fastmap[h].id = id;
91 head->fastmap[h].iif = iif;
92 head->fastmap[h].filter = f;
93 spin_unlock_bh(&fastmap_lock);
94}
95
96static inline int route4_hash_to(u32 id)
97{
98 return id & 0xFF;
99}
100
101static inline int route4_hash_from(u32 id)
102{
103 return (id >> 16) & 0xF;
104}
105
106static inline int route4_hash_iif(int iif)
107{
108 return 16 + ((iif >> 16) & 0xF);
109}
110
111static inline int route4_hash_wild(void)
112{
113 return 32;
114}
115
116#define ROUTE4_APPLY_RESULT() \
117{ \
118 *res = f->res; \
119 if (tcf_exts_has_actions(&f->exts)) { \
120 int r = tcf_exts_exec(skb, &f->exts, res); \
121 if (r < 0) { \
122 dont_cache = 1; \
123 continue; \
124 } \
125 return r; \
126 } else if (!dont_cache) \
127 route4_set_fastmap(head, id, iif, f); \
128 return 0; \
129}
130
131static int route4_classify(struct sk_buff *skb, const struct tcf_proto *tp,
132 struct tcf_result *res)
133{
134 struct route4_head *head = rcu_dereference_bh(tp->root);
135 struct dst_entry *dst;
136 struct route4_bucket *b;
137 struct route4_filter *f;
138 u32 id, h;
139 int iif, dont_cache = 0;
140
141 dst = skb_dst(skb);
142 if (!dst)
143 goto failure;
144
145 id = dst->tclassid;
146
147 iif = inet_iif(skb);
148
149 h = route4_fastmap_hash(id, iif);
150
151 spin_lock(&fastmap_lock);
152 if (id == head->fastmap[h].id &&
153 iif == head->fastmap[h].iif &&
154 (f = head->fastmap[h].filter) != NULL) {
155 if (f == ROUTE4_FAILURE) {
156 spin_unlock(&fastmap_lock);
157 goto failure;
158 }
159
160 *res = f->res;
161 spin_unlock(&fastmap_lock);
162 return 0;
163 }
164 spin_unlock(&fastmap_lock);
165
166 h = route4_hash_to(id);
167
168restart:
169 b = rcu_dereference_bh(head->table[h]);
170 if (b) {
171 for (f = rcu_dereference_bh(b->ht[route4_hash_from(id)]);
172 f;
173 f = rcu_dereference_bh(f->next))
174 if (f->id == id)
175 ROUTE4_APPLY_RESULT();
176
177 for (f = rcu_dereference_bh(b->ht[route4_hash_iif(iif)]);
178 f;
179 f = rcu_dereference_bh(f->next))
180 if (f->iif == iif)
181 ROUTE4_APPLY_RESULT();
182
183 for (f = rcu_dereference_bh(b->ht[route4_hash_wild()]);
184 f;
185 f = rcu_dereference_bh(f->next))
186 ROUTE4_APPLY_RESULT();
187 }
188 if (h < 256) {
189 h = 256;
190 id &= ~0xFFFF;
191 goto restart;
192 }
193
194 if (!dont_cache)
195 route4_set_fastmap(head, id, iif, ROUTE4_FAILURE);
196failure:
197 return -1;
198}
199
200static inline u32 to_hash(u32 id)
201{
202 u32 h = id & 0xFF;
203
204 if (id & 0x8000)
205 h += 256;
206 return h;
207}
208
209static inline u32 from_hash(u32 id)
210{
211 id &= 0xFFFF;
212 if (id == 0xFFFF)
213 return 32;
214 if (!(id & 0x8000)) {
215 if (id > 255)
216 return 256;
217 return id & 0xF;
218 }
219 return 16 + (id & 0xF);
220}
221
222static void *route4_get(struct tcf_proto *tp, u32 handle)
223{
224 struct route4_head *head = rtnl_dereference(tp->root);
225 struct route4_bucket *b;
226 struct route4_filter *f;
227 unsigned int h1, h2;
228
229 h1 = to_hash(handle);
230 if (h1 > 256)
231 return NULL;
232
233 h2 = from_hash(handle >> 16);
234 if (h2 > 32)
235 return NULL;
236
237 b = rtnl_dereference(head->table[h1]);
238 if (b) {
239 for (f = rtnl_dereference(b->ht[h2]);
240 f;
241 f = rtnl_dereference(f->next))
242 if (f->handle == handle)
243 return f;
244 }
245 return NULL;
246}
247
248static int route4_init(struct tcf_proto *tp)
249{
250 struct route4_head *head;
251
252 head = kzalloc(sizeof(struct route4_head), GFP_KERNEL);
253 if (head == NULL)
254 return -ENOBUFS;
255
256 rcu_assign_pointer(tp->root, head);
257 return 0;
258}
259
260static void __route4_delete_filter(struct route4_filter *f)
261{
262 tcf_exts_destroy(&f->exts);
263 tcf_exts_put_net(&f->exts);
264 kfree(f);
265}
266
267static void route4_delete_filter_work(struct work_struct *work)
268{
269 struct route4_filter *f = container_of(work, struct route4_filter, work);
270
271 rtnl_lock();
272 __route4_delete_filter(f);
273 rtnl_unlock();
274}
275
276static void route4_delete_filter(struct rcu_head *head)
277{
278 struct route4_filter *f = container_of(head, struct route4_filter, rcu);
279
280 INIT_WORK(&f->work, route4_delete_filter_work);
281 tcf_queue_work(&f->work);
282}
283
284static void route4_destroy(struct tcf_proto *tp, struct netlink_ext_ack *extack)
285{
286 struct route4_head *head = rtnl_dereference(tp->root);
287 int h1, h2;
288
289 if (head == NULL)
290 return;
291
292 for (h1 = 0; h1 <= 256; h1++) {
293 struct route4_bucket *b;
294
295 b = rtnl_dereference(head->table[h1]);
296 if (b) {
297 for (h2 = 0; h2 <= 32; h2++) {
298 struct route4_filter *f;
299
300 while ((f = rtnl_dereference(b->ht[h2])) != NULL) {
301 struct route4_filter *next;
302
303 next = rtnl_dereference(f->next);
304 RCU_INIT_POINTER(b->ht[h2], next);
305 tcf_unbind_filter(tp, &f->res);
306 if (tcf_exts_get_net(&f->exts))
307 call_rcu(&f->rcu, route4_delete_filter);
308 else
309 __route4_delete_filter(f);
310 }
311 }
312 RCU_INIT_POINTER(head->table[h1], NULL);
313 kfree_rcu(b, rcu);
314 }
315 }
316 kfree_rcu(head, rcu);
317}
318
319static int route4_delete(struct tcf_proto *tp, void *arg, bool *last,
320 struct netlink_ext_ack *extack)
321{
322 struct route4_head *head = rtnl_dereference(tp->root);
323 struct route4_filter *f = arg;
324 struct route4_filter __rcu **fp;
325 struct route4_filter *nf;
326 struct route4_bucket *b;
327 unsigned int h = 0;
328 int i, h1;
329
330 if (!head || !f)
331 return -EINVAL;
332
333 h = f->handle;
334 b = f->bkt;
335
336 fp = &b->ht[from_hash(h >> 16)];
337 for (nf = rtnl_dereference(*fp); nf;
338 fp = &nf->next, nf = rtnl_dereference(*fp)) {
339 if (nf == f) {
340
341 RCU_INIT_POINTER(*fp, rtnl_dereference(f->next));
342
343
344
345
346
347 route4_reset_fastmap(head);
348
349
350 tcf_unbind_filter(tp, &f->res);
351 tcf_exts_get_net(&f->exts);
352 call_rcu(&f->rcu, route4_delete_filter);
353
354
355 for (i = 0; i <= 32; i++) {
356 struct route4_filter *rt;
357
358 rt = rtnl_dereference(b->ht[i]);
359 if (rt)
360 goto out;
361 }
362
363
364 RCU_INIT_POINTER(head->table[to_hash(h)], NULL);
365 kfree_rcu(b, rcu);
366 break;
367 }
368 }
369
370out:
371 *last = true;
372 for (h1 = 0; h1 <= 256; h1++) {
373 if (rcu_access_pointer(head->table[h1])) {
374 *last = false;
375 break;
376 }
377 }
378
379 return 0;
380}
381
382static const struct nla_policy route4_policy[TCA_ROUTE4_MAX + 1] = {
383 [TCA_ROUTE4_CLASSID] = { .type = NLA_U32 },
384 [TCA_ROUTE4_TO] = { .type = NLA_U32 },
385 [TCA_ROUTE4_FROM] = { .type = NLA_U32 },
386 [TCA_ROUTE4_IIF] = { .type = NLA_U32 },
387};
388
389static int route4_set_parms(struct net *net, struct tcf_proto *tp,
390 unsigned long base, struct route4_filter *f,
391 u32 handle, struct route4_head *head,
392 struct nlattr **tb, struct nlattr *est, int new,
393 bool ovr, struct netlink_ext_ack *extack)
394{
395 u32 id = 0, to = 0, nhandle = 0x8000;
396 struct route4_filter *fp;
397 unsigned int h1;
398 struct route4_bucket *b;
399 int err;
400
401 err = tcf_exts_validate(net, tp, tb, est, &f->exts, ovr, extack);
402 if (err < 0)
403 return err;
404
405 if (tb[TCA_ROUTE4_TO]) {
406 if (new && handle & 0x8000)
407 return -EINVAL;
408 to = nla_get_u32(tb[TCA_ROUTE4_TO]);
409 if (to > 0xFF)
410 return -EINVAL;
411 nhandle = to;
412 }
413
414 if (tb[TCA_ROUTE4_FROM]) {
415 if (tb[TCA_ROUTE4_IIF])
416 return -EINVAL;
417 id = nla_get_u32(tb[TCA_ROUTE4_FROM]);
418 if (id > 0xFF)
419 return -EINVAL;
420 nhandle |= id << 16;
421 } else if (tb[TCA_ROUTE4_IIF]) {
422 id = nla_get_u32(tb[TCA_ROUTE4_IIF]);
423 if (id > 0x7FFF)
424 return -EINVAL;
425 nhandle |= (id | 0x8000) << 16;
426 } else
427 nhandle |= 0xFFFF << 16;
428
429 if (handle && new) {
430 nhandle |= handle & 0x7F00;
431 if (nhandle != handle)
432 return -EINVAL;
433 }
434
435 h1 = to_hash(nhandle);
436 b = rtnl_dereference(head->table[h1]);
437 if (!b) {
438 b = kzalloc(sizeof(struct route4_bucket), GFP_KERNEL);
439 if (b == NULL)
440 return -ENOBUFS;
441
442 rcu_assign_pointer(head->table[h1], b);
443 } else {
444 unsigned int h2 = from_hash(nhandle >> 16);
445
446 for (fp = rtnl_dereference(b->ht[h2]);
447 fp;
448 fp = rtnl_dereference(fp->next))
449 if (fp->handle == f->handle)
450 return -EEXIST;
451 }
452
453 if (tb[TCA_ROUTE4_TO])
454 f->id = to;
455
456 if (tb[TCA_ROUTE4_FROM])
457 f->id = to | id<<16;
458 else if (tb[TCA_ROUTE4_IIF])
459 f->iif = id;
460
461 f->handle = nhandle;
462 f->bkt = b;
463 f->tp = tp;
464
465 if (tb[TCA_ROUTE4_CLASSID]) {
466 f->res.classid = nla_get_u32(tb[TCA_ROUTE4_CLASSID]);
467 tcf_bind_filter(tp, &f->res, base);
468 }
469
470 return 0;
471}
472
473static int route4_change(struct net *net, struct sk_buff *in_skb,
474 struct tcf_proto *tp, unsigned long base, u32 handle,
475 struct nlattr **tca, void **arg, bool ovr,
476 struct netlink_ext_ack *extack)
477{
478 struct route4_head *head = rtnl_dereference(tp->root);
479 struct route4_filter __rcu **fp;
480 struct route4_filter *fold, *f1, *pfp, *f = NULL;
481 struct route4_bucket *b;
482 struct nlattr *opt = tca[TCA_OPTIONS];
483 struct nlattr *tb[TCA_ROUTE4_MAX + 1];
484 unsigned int h, th;
485 int err;
486 bool new = true;
487
488 if (opt == NULL)
489 return handle ? -EINVAL : 0;
490
491 err = nla_parse_nested(tb, TCA_ROUTE4_MAX, opt, route4_policy, NULL);
492 if (err < 0)
493 return err;
494
495 fold = *arg;
496 if (fold && handle && fold->handle != handle)
497 return -EINVAL;
498
499 err = -ENOBUFS;
500 f = kzalloc(sizeof(struct route4_filter), GFP_KERNEL);
501 if (!f)
502 goto errout;
503
504 err = tcf_exts_init(&f->exts, TCA_ROUTE4_ACT, TCA_ROUTE4_POLICE);
505 if (err < 0)
506 goto errout;
507
508 if (fold) {
509 f->id = fold->id;
510 f->iif = fold->iif;
511 f->res = fold->res;
512 f->handle = fold->handle;
513
514 f->tp = fold->tp;
515 f->bkt = fold->bkt;
516 new = false;
517 }
518
519 err = route4_set_parms(net, tp, base, f, handle, head, tb,
520 tca[TCA_RATE], new, ovr, extack);
521 if (err < 0)
522 goto errout;
523
524 h = from_hash(f->handle >> 16);
525 fp = &f->bkt->ht[h];
526 for (pfp = rtnl_dereference(*fp);
527 (f1 = rtnl_dereference(*fp)) != NULL;
528 fp = &f1->next)
529 if (f->handle < f1->handle)
530 break;
531
532 tcf_block_netif_keep_dst(tp->chain->block);
533 rcu_assign_pointer(f->next, f1);
534 rcu_assign_pointer(*fp, f);
535
536 if (fold && fold->handle && f->handle != fold->handle) {
537 th = to_hash(fold->handle);
538 h = from_hash(fold->handle >> 16);
539 b = rtnl_dereference(head->table[th]);
540 if (b) {
541 fp = &b->ht[h];
542 for (pfp = rtnl_dereference(*fp); pfp;
543 fp = &pfp->next, pfp = rtnl_dereference(*fp)) {
544 if (pfp == f) {
545 *fp = f->next;
546 break;
547 }
548 }
549 }
550 }
551
552 route4_reset_fastmap(head);
553 *arg = f;
554 if (fold) {
555 tcf_unbind_filter(tp, &fold->res);
556 tcf_exts_get_net(&fold->exts);
557 call_rcu(&fold->rcu, route4_delete_filter);
558 }
559 return 0;
560
561errout:
562 if (f)
563 tcf_exts_destroy(&f->exts);
564 kfree(f);
565 return err;
566}
567
568static void route4_walk(struct tcf_proto *tp, struct tcf_walker *arg)
569{
570 struct route4_head *head = rtnl_dereference(tp->root);
571 unsigned int h, h1;
572
573 if (head == NULL)
574 arg->stop = 1;
575
576 if (arg->stop)
577 return;
578
579 for (h = 0; h <= 256; h++) {
580 struct route4_bucket *b = rtnl_dereference(head->table[h]);
581
582 if (b) {
583 for (h1 = 0; h1 <= 32; h1++) {
584 struct route4_filter *f;
585
586 for (f = rtnl_dereference(b->ht[h1]);
587 f;
588 f = rtnl_dereference(f->next)) {
589 if (arg->count < arg->skip) {
590 arg->count++;
591 continue;
592 }
593 if (arg->fn(tp, f, arg) < 0) {
594 arg->stop = 1;
595 return;
596 }
597 arg->count++;
598 }
599 }
600 }
601 }
602}
603
604static int route4_dump(struct net *net, struct tcf_proto *tp, void *fh,
605 struct sk_buff *skb, struct tcmsg *t)
606{
607 struct route4_filter *f = fh;
608 struct nlattr *nest;
609 u32 id;
610
611 if (f == NULL)
612 return skb->len;
613
614 t->tcm_handle = f->handle;
615
616 nest = nla_nest_start(skb, TCA_OPTIONS);
617 if (nest == NULL)
618 goto nla_put_failure;
619
620 if (!(f->handle & 0x8000)) {
621 id = f->id & 0xFF;
622 if (nla_put_u32(skb, TCA_ROUTE4_TO, id))
623 goto nla_put_failure;
624 }
625 if (f->handle & 0x80000000) {
626 if ((f->handle >> 16) != 0xFFFF &&
627 nla_put_u32(skb, TCA_ROUTE4_IIF, f->iif))
628 goto nla_put_failure;
629 } else {
630 id = f->id >> 16;
631 if (nla_put_u32(skb, TCA_ROUTE4_FROM, id))
632 goto nla_put_failure;
633 }
634 if (f->res.classid &&
635 nla_put_u32(skb, TCA_ROUTE4_CLASSID, f->res.classid))
636 goto nla_put_failure;
637
638 if (tcf_exts_dump(skb, &f->exts) < 0)
639 goto nla_put_failure;
640
641 nla_nest_end(skb, nest);
642
643 if (tcf_exts_dump_stats(skb, &f->exts) < 0)
644 goto nla_put_failure;
645
646 return skb->len;
647
648nla_put_failure:
649 nla_nest_cancel(skb, nest);
650 return -1;
651}
652
653static void route4_bind_class(void *fh, u32 classid, unsigned long cl)
654{
655 struct route4_filter *f = fh;
656
657 if (f && f->res.classid == classid)
658 f->res.class = cl;
659}
660
661static struct tcf_proto_ops cls_route4_ops __read_mostly = {
662 .kind = "route",
663 .classify = route4_classify,
664 .init = route4_init,
665 .destroy = route4_destroy,
666 .get = route4_get,
667 .change = route4_change,
668 .delete = route4_delete,
669 .walk = route4_walk,
670 .dump = route4_dump,
671 .bind_class = route4_bind_class,
672 .owner = THIS_MODULE,
673};
674
675static int __init init_route4(void)
676{
677 return register_tcf_proto_ops(&cls_route4_ops);
678}
679
680static void __exit exit_route4(void)
681{
682 unregister_tcf_proto_ops(&cls_route4_ops);
683}
684
685module_init(init_route4)
686module_exit(exit_route4)
687MODULE_LICENSE("GPL");
688
