1 /*
2 * net/sched/cls_u32.c Ugly (or Universal) 32bit key Packet Classifier.
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 * The filters are packed to hash tables of key nodes
12 * with a set of 32bit key/mask pairs at every node.
13 * Nodes reference next level hash tables etc.
14 *
15 * This scheme is the best universal classifier I managed to
16 * invent; it is not super-fast, but it is not slow (provided you
17 * program it correctly), and general enough. And its relative
18 * speed grows as the number of rules becomes larger.
19 *
20 * It seems that it represents the best middle point between
21 * speed and manageability both by human and by machine.
22 *
23 * It is especially useful for link sharing combined with QoS;
24 * pure RSVP doesn't need such a general approach and can use
25 * much simpler (and faster) schemes, sort of cls_rsvp.c.
26 *
27 * JHS: We should remove the CONFIG_NET_CLS_IND from here
28 * eventually when the meta match extension is made available
29 *
30 * nfmark match added by Catalin(ux aka Dino) BOIE <catab at umbrella.ro>
31 */
32
33 #include <linux/module.h>
34 #include <linux/slab.h>
35 #include <linux/types.h>
36 #include <linux/kernel.h>
37 #include <linux/string.h>
38 #include <linux/errno.h>
39 #include <linux/percpu.h>
40 #include <linux/rtnetlink.h>
41 #include <linux/skbuff.h>
42 #include <linux/bitmap.h>
43 #include <net/netlink.h>
44 #include <net/act_api.h>
45 #include <net/pkt_cls.h>
46 #include <linux/netdevice.h>
47
48 struct tc_u_knode {
49 struct tc_u_knode __rcu *next;
50 u32 handle;
51 struct tc_u_hnode __rcu *ht_up;
52 struct tcf_exts exts;
53 #ifdef CONFIG_NET_CLS_IND
54 int ifindex;
55 #endif
56 u8 fshift;
57 struct tcf_result res;
58 struct tc_u_hnode __rcu *ht_down;
59 #ifdef CONFIG_CLS_U32_PERF
60 struct tc_u32_pcnt __percpu *pf;
61 #endif
62 u32 flags;
63 #ifdef CONFIG_CLS_U32_MARK
64 u32 val;
65 u32 mask;
66 u32 __percpu *pcpu_success;
67 #endif
68 struct tcf_proto *tp;
69 struct rcu_head rcu;
70 /* The 'sel' field MUST be the last field in structure to allow for
71 * tc_u32_keys allocated at end of structure.
72 */
73 struct tc_u32_sel sel;
74 };
75
76 struct tc_u_hnode {
77 struct tc_u_hnode __rcu *next;
78 u32 handle;
79 u32 prio;
80 struct tc_u_common *tp_c;
81 int refcnt;
82 unsigned int divisor;
83 struct rcu_head rcu;
84 /* The 'ht' field MUST be the last field in structure to allow for
85 * more entries allocated at end of structure.
86 */
87 struct tc_u_knode __rcu *ht[1];
88 };
89
90 struct tc_u_common {
91 struct tc_u_hnode __rcu *hlist;
92 struct Qdisc *q;
93 int refcnt;
94 u32 hgenerator;
95 struct rcu_head rcu;
96 };
97
u32_hash_fold(__be32 key,const struct tc_u32_sel * sel,u8 fshift)98 static inline unsigned int u32_hash_fold(__be32 key,
99 const struct tc_u32_sel *sel,
100 u8 fshift)
101 {
102 unsigned int h = ntohl(key & sel->hmask) >> fshift;
103
104 return h;
105 }
106
u32_classify(struct sk_buff * skb,const struct tcf_proto * tp,struct tcf_result * res)107 static int u32_classify(struct sk_buff *skb, const struct tcf_proto *tp,
108 struct tcf_result *res)
109 {
110 struct {
111 struct tc_u_knode *knode;
112 unsigned int off;
113 } stack[TC_U32_MAXDEPTH];
114
115 struct tc_u_hnode *ht = rcu_dereference_bh(tp->root);
116 unsigned int off = skb_network_offset(skb);
117 struct tc_u_knode *n;
118 int sdepth = 0;
119 int off2 = 0;
120 int sel = 0;
121 #ifdef CONFIG_CLS_U32_PERF
122 int j;
123 #endif
124 int i, r;
125
126 next_ht:
127 n = rcu_dereference_bh(ht->ht[sel]);
128
129 next_knode:
130 if (n) {
131 struct tc_u32_key *key = n->sel.keys;
132
133 #ifdef CONFIG_CLS_U32_PERF
134 __this_cpu_inc(n->pf->rcnt);
135 j = 0;
136 #endif
137
138 if (tc_skip_sw(n->flags)) {
139 n = rcu_dereference_bh(n->next);
140 goto next_knode;
141 }
142
143 #ifdef CONFIG_CLS_U32_MARK
144 if ((skb->mark & n->mask) != n->val) {
145 n = rcu_dereference_bh(n->next);
146 goto next_knode;
147 } else {
148 __this_cpu_inc(*n->pcpu_success);
149 }
150 #endif
151
152 for (i = n->sel.nkeys; i > 0; i--, key++) {
153 int toff = off + key->off + (off2 & key->offmask);
154 __be32 *data, hdata;
155
156 if (skb_headroom(skb) + toff > INT_MAX)
157 goto out;
158
159 data = skb_header_pointer(skb, toff, 4, &hdata);
160 if (!data)
161 goto out;
162 if ((*data ^ key->val) & key->mask) {
163 n = rcu_dereference_bh(n->next);
164 goto next_knode;
165 }
166 #ifdef CONFIG_CLS_U32_PERF
167 __this_cpu_inc(n->pf->kcnts[j]);
168 j++;
169 #endif
170 }
171
172 ht = rcu_dereference_bh(n->ht_down);
173 if (!ht) {
174 check_terminal:
175 if (n->sel.flags & TC_U32_TERMINAL) {
176
177 *res = n->res;
178 #ifdef CONFIG_NET_CLS_IND
179 if (!tcf_match_indev(skb, n->ifindex)) {
180 n = rcu_dereference_bh(n->next);
181 goto next_knode;
182 }
183 #endif
184 #ifdef CONFIG_CLS_U32_PERF
185 __this_cpu_inc(n->pf->rhit);
186 #endif
187 r = tcf_exts_exec(skb, &n->exts, res);
188 if (r < 0) {
189 n = rcu_dereference_bh(n->next);
190 goto next_knode;
191 }
192
193 return r;
194 }
195 n = rcu_dereference_bh(n->next);
196 goto next_knode;
197 }
198
199 /* PUSH */
200 if (sdepth >= TC_U32_MAXDEPTH)
201 goto deadloop;
202 stack[sdepth].knode = n;
203 stack[sdepth].off = off;
204 sdepth++;
205
206 ht = rcu_dereference_bh(n->ht_down);
207 sel = 0;
208 if (ht->divisor) {
209 __be32 *data, hdata;
210
211 data = skb_header_pointer(skb, off + n->sel.hoff, 4,
212 &hdata);
213 if (!data)
214 goto out;
215 sel = ht->divisor & u32_hash_fold(*data, &n->sel,
216 n->fshift);
217 }
218 if (!(n->sel.flags & (TC_U32_VAROFFSET | TC_U32_OFFSET | TC_U32_EAT)))
219 goto next_ht;
220
221 if (n->sel.flags & (TC_U32_OFFSET | TC_U32_VAROFFSET)) {
222 off2 = n->sel.off + 3;
223 if (n->sel.flags & TC_U32_VAROFFSET) {
224 __be16 *data, hdata;
225
226 data = skb_header_pointer(skb,
227 off + n->sel.offoff,
228 2, &hdata);
229 if (!data)
230 goto out;
231 off2 += ntohs(n->sel.offmask & *data) >>
232 n->sel.offshift;
233 }
234 off2 &= ~3;
235 }
236 if (n->sel.flags & TC_U32_EAT) {
237 off += off2;
238 off2 = 0;
239 }
240
241 if (off < skb->len)
242 goto next_ht;
243 }
244
245 /* POP */
246 if (sdepth--) {
247 n = stack[sdepth].knode;
248 ht = rcu_dereference_bh(n->ht_up);
249 off = stack[sdepth].off;
250 goto check_terminal;
251 }
252 out:
253 return -1;
254
255 deadloop:
256 net_warn_ratelimited("cls_u32: dead loop\n");
257 return -1;
258 }
259
u32_lookup_ht(struct tc_u_common * tp_c,u32 handle)260 static struct tc_u_hnode *u32_lookup_ht(struct tc_u_common *tp_c, u32 handle)
261 {
262 struct tc_u_hnode *ht;
263
264 for (ht = rtnl_dereference(tp_c->hlist);
265 ht;
266 ht = rtnl_dereference(ht->next))
267 if (ht->handle == handle)
268 break;
269
270 return ht;
271 }
272
u32_lookup_key(struct tc_u_hnode * ht,u32 handle)273 static struct tc_u_knode *u32_lookup_key(struct tc_u_hnode *ht, u32 handle)
274 {
275 unsigned int sel;
276 struct tc_u_knode *n = NULL;
277
278 sel = TC_U32_HASH(handle);
279 if (sel > ht->divisor)
280 goto out;
281
282 for (n = rtnl_dereference(ht->ht[sel]);
283 n;
284 n = rtnl_dereference(n->next))
285 if (n->handle == handle)
286 break;
287 out:
288 return n;
289 }
290
291
u32_get(struct tcf_proto * tp,u32 handle)292 static unsigned long u32_get(struct tcf_proto *tp, u32 handle)
293 {
294 struct tc_u_hnode *ht;
295 struct tc_u_common *tp_c = tp->data;
296
297 if (TC_U32_HTID(handle) == TC_U32_ROOT)
298 ht = rtnl_dereference(tp->root);
299 else
300 ht = u32_lookup_ht(tp_c, TC_U32_HTID(handle));
301
302 if (!ht)
303 return 0;
304
305 if (TC_U32_KEY(handle) == 0)
306 return (unsigned long)ht;
307
308 return (unsigned long)u32_lookup_key(ht, handle);
309 }
310
gen_new_htid(struct tc_u_common * tp_c)311 static u32 gen_new_htid(struct tc_u_common *tp_c)
312 {
313 int i = 0x800;
314
315 /* hgenerator only used inside rtnl lock it is safe to increment
316 * without read _copy_ update semantics
317 */
318 do {
319 if (++tp_c->hgenerator == 0x7FF)
320 tp_c->hgenerator = 1;
321 } while (--i > 0 && u32_lookup_ht(tp_c, (tp_c->hgenerator|0x800)<<20));
322
323 return i > 0 ? (tp_c->hgenerator|0x800)<<20 : 0;
324 }
325
u32_init(struct tcf_proto * tp)326 static int u32_init(struct tcf_proto *tp)
327 {
328 struct tc_u_hnode *root_ht;
329 struct tc_u_common *tp_c;
330
331 tp_c = tp->q->u32_node;
332
333 root_ht = kzalloc(sizeof(*root_ht), GFP_KERNEL);
334 if (root_ht == NULL)
335 return -ENOBUFS;
336
337 root_ht->divisor = 0;
338 root_ht->refcnt++;
339 root_ht->handle = tp_c ? gen_new_htid(tp_c) : 0x80000000;
340 root_ht->prio = tp->prio;
341
342 if (tp_c == NULL) {
343 tp_c = kzalloc(sizeof(*tp_c), GFP_KERNEL);
344 if (tp_c == NULL) {
345 kfree(root_ht);
346 return -ENOBUFS;
347 }
348 tp_c->q = tp->q;
349 tp->q->u32_node = tp_c;
350 }
351
352 tp_c->refcnt++;
353 RCU_INIT_POINTER(root_ht->next, tp_c->hlist);
354 rcu_assign_pointer(tp_c->hlist, root_ht);
355 root_ht->tp_c = tp_c;
356
357 rcu_assign_pointer(tp->root, root_ht);
358 tp->data = tp_c;
359 return 0;
360 }
361
u32_destroy_key(struct tcf_proto * tp,struct tc_u_knode * n,bool free_pf)362 static int u32_destroy_key(struct tcf_proto *tp, struct tc_u_knode *n,
363 bool free_pf)
364 {
365 tcf_exts_destroy(&n->exts);
366 if (n->ht_down)
367 n->ht_down->refcnt--;
368 #ifdef CONFIG_CLS_U32_PERF
369 if (free_pf)
370 free_percpu(n->pf);
371 #endif
372 #ifdef CONFIG_CLS_U32_MARK
373 if (free_pf)
374 free_percpu(n->pcpu_success);
375 #endif
376 kfree(n);
377 return 0;
378 }
379
380 /* u32_delete_key_rcu should be called when free'ing a copied
381 * version of a tc_u_knode obtained from u32_init_knode(). When
382 * copies are obtained from u32_init_knode() the statistics are
383 * shared between the old and new copies to allow readers to
384 * continue to update the statistics during the copy. To support
385 * this the u32_delete_key_rcu variant does not free the percpu
386 * statistics.
387 */
u32_delete_key_rcu(struct rcu_head * rcu)388 static void u32_delete_key_rcu(struct rcu_head *rcu)
389 {
390 struct tc_u_knode *key = container_of(rcu, struct tc_u_knode, rcu);
391
392 u32_destroy_key(key->tp, key, false);
393 }
394
395 /* u32_delete_key_freepf_rcu is the rcu callback variant
396 * that free's the entire structure including the statistics
397 * percpu variables. Only use this if the key is not a copy
398 * returned by u32_init_knode(). See u32_delete_key_rcu()
399 * for the variant that should be used with keys return from
400 * u32_init_knode()
401 */
u32_delete_key_freepf_rcu(struct rcu_head * rcu)402 static void u32_delete_key_freepf_rcu(struct rcu_head *rcu)
403 {
404 struct tc_u_knode *key = container_of(rcu, struct tc_u_knode, rcu);
405
406 u32_destroy_key(key->tp, key, true);
407 }
408
u32_delete_key(struct tcf_proto * tp,struct tc_u_knode * key)409 static int u32_delete_key(struct tcf_proto *tp, struct tc_u_knode *key)
410 {
411 struct tc_u_knode __rcu **kp;
412 struct tc_u_knode *pkp;
413 struct tc_u_hnode *ht = rtnl_dereference(key->ht_up);
414
415 if (ht) {
416 kp = &ht->ht[TC_U32_HASH(key->handle)];
417 for (pkp = rtnl_dereference(*kp); pkp;
418 kp = &pkp->next, pkp = rtnl_dereference(*kp)) {
419 if (pkp == key) {
420 RCU_INIT_POINTER(*kp, key->next);
421
422 tcf_unbind_filter(tp, &key->res);
423 call_rcu(&key->rcu, u32_delete_key_freepf_rcu);
424 return 0;
425 }
426 }
427 }
428 WARN_ON(1);
429 return 0;
430 }
431
u32_remove_hw_knode(struct tcf_proto * tp,u32 handle)432 static void u32_remove_hw_knode(struct tcf_proto *tp, u32 handle)
433 {
434 struct net_device *dev = tp->q->dev_queue->dev;
435 struct tc_cls_u32_offload u32_offload = {0};
436 struct tc_to_netdev offload;
437
438 offload.type = TC_SETUP_CLSU32;
439 offload.cls_u32 = &u32_offload;
440
441 if (tc_should_offload(dev, tp, 0)) {
442 offload.cls_u32->command = TC_CLSU32_DELETE_KNODE;
443 offload.cls_u32->knode.handle = handle;
444 dev->netdev_ops->ndo_setup_tc(dev, tp->q->handle,
445 tp->protocol, &offload);
446 }
447 }
448
u32_replace_hw_hnode(struct tcf_proto * tp,struct tc_u_hnode * h,u32 flags)449 static int u32_replace_hw_hnode(struct tcf_proto *tp, struct tc_u_hnode *h,
450 u32 flags)
451 {
452 struct net_device *dev = tp->q->dev_queue->dev;
453 struct tc_cls_u32_offload u32_offload = {0};
454 struct tc_to_netdev offload;
455 int err;
456
457 if (!tc_should_offload(dev, tp, flags))
458 return tc_skip_sw(flags) ? -EINVAL : 0;
459
460 offload.type = TC_SETUP_CLSU32;
461 offload.cls_u32 = &u32_offload;
462
463 offload.cls_u32->command = TC_CLSU32_NEW_HNODE;
464 offload.cls_u32->hnode.divisor = h->divisor;
465 offload.cls_u32->hnode.handle = h->handle;
466 offload.cls_u32->hnode.prio = h->prio;
467
468 err = dev->netdev_ops->ndo_setup_tc(dev, tp->q->handle,
469 tp->protocol, &offload);
470 if (tc_skip_sw(flags))
471 return err;
472
473 return 0;
474 }
475
u32_clear_hw_hnode(struct tcf_proto * tp,struct tc_u_hnode * h)476 static void u32_clear_hw_hnode(struct tcf_proto *tp, struct tc_u_hnode *h)
477 {
478 struct net_device *dev = tp->q->dev_queue->dev;
479 struct tc_cls_u32_offload u32_offload = {0};
480 struct tc_to_netdev offload;
481
482 offload.type = TC_SETUP_CLSU32;
483 offload.cls_u32 = &u32_offload;
484
485 if (tc_should_offload(dev, tp, 0)) {
486 offload.cls_u32->command = TC_CLSU32_DELETE_HNODE;
487 offload.cls_u32->hnode.divisor = h->divisor;
488 offload.cls_u32->hnode.handle = h->handle;
489 offload.cls_u32->hnode.prio = h->prio;
490
491 dev->netdev_ops->ndo_setup_tc(dev, tp->q->handle,
492 tp->protocol, &offload);
493 }
494 }
495
u32_replace_hw_knode(struct tcf_proto * tp,struct tc_u_knode * n,u32 flags)496 static int u32_replace_hw_knode(struct tcf_proto *tp, struct tc_u_knode *n,
497 u32 flags)
498 {
499 struct tc_u_hnode *ht = rtnl_dereference(n->ht_down);
500 struct net_device *dev = tp->q->dev_queue->dev;
501 struct tc_cls_u32_offload u32_offload = {0};
502 struct tc_to_netdev offload;
503 int err;
504
505 offload.type = TC_SETUP_CLSU32;
506 offload.cls_u32 = &u32_offload;
507
508 if (!tc_should_offload(dev, tp, flags))
509 return tc_skip_sw(flags) ? -EINVAL : 0;
510
511 offload.cls_u32->command = TC_CLSU32_REPLACE_KNODE;
512 offload.cls_u32->knode.handle = n->handle;
513 offload.cls_u32->knode.fshift = n->fshift;
514 #ifdef CONFIG_CLS_U32_MARK
515 offload.cls_u32->knode.val = n->val;
516 offload.cls_u32->knode.mask = n->mask;
517 #else
518 offload.cls_u32->knode.val = 0;
519 offload.cls_u32->knode.mask = 0;
520 #endif
521 offload.cls_u32->knode.sel = &n->sel;
522 offload.cls_u32->knode.exts = &n->exts;
523 if (n->ht_down)
524 offload.cls_u32->knode.link_handle = ht->handle;
525
526 err = dev->netdev_ops->ndo_setup_tc(dev, tp->q->handle,
527 tp->protocol, &offload);
528 if (tc_skip_sw(flags))
529 return err;
530
531 return 0;
532 }
533
u32_clear_hnode(struct tcf_proto * tp,struct tc_u_hnode * ht)534 static void u32_clear_hnode(struct tcf_proto *tp, struct tc_u_hnode *ht)
535 {
536 struct tc_u_knode *n;
537 unsigned int h;
538
539 for (h = 0; h <= ht->divisor; h++) {
540 while ((n = rtnl_dereference(ht->ht[h])) != NULL) {
541 RCU_INIT_POINTER(ht->ht[h],
542 rtnl_dereference(n->next));
543 tcf_unbind_filter(tp, &n->res);
544 u32_remove_hw_knode(tp, n->handle);
545 call_rcu(&n->rcu, u32_delete_key_freepf_rcu);
546 }
547 }
548 }
549
u32_destroy_hnode(struct tcf_proto * tp,struct tc_u_hnode * ht)550 static int u32_destroy_hnode(struct tcf_proto *tp, struct tc_u_hnode *ht)
551 {
552 struct tc_u_common *tp_c = tp->data;
553 struct tc_u_hnode __rcu **hn;
554 struct tc_u_hnode *phn;
555
556 WARN_ON(ht->refcnt);
557
558 u32_clear_hnode(tp, ht);
559
560 hn = &tp_c->hlist;
561 for (phn = rtnl_dereference(*hn);
562 phn;
563 hn = &phn->next, phn = rtnl_dereference(*hn)) {
564 if (phn == ht) {
565 u32_clear_hw_hnode(tp, ht);
566 RCU_INIT_POINTER(*hn, ht->next);
567 kfree_rcu(ht, rcu);
568 return 0;
569 }
570 }
571
572 return -ENOENT;
573 }
574
ht_empty(struct tc_u_hnode * ht)575 static bool ht_empty(struct tc_u_hnode *ht)
576 {
577 unsigned int h;
578
579 for (h = 0; h <= ht->divisor; h++)
580 if (rcu_access_pointer(ht->ht[h]))
581 return false;
582
583 return true;
584 }
585
u32_destroy(struct tcf_proto * tp,bool force)586 static bool u32_destroy(struct tcf_proto *tp, bool force)
587 {
588 struct tc_u_common *tp_c = tp->data;
589 struct tc_u_hnode *root_ht = rtnl_dereference(tp->root);
590
591 WARN_ON(root_ht == NULL);
592
593 if (!force) {
594 if (root_ht) {
595 if (root_ht->refcnt > 1)
596 return false;
597 if (root_ht->refcnt == 1) {
598 if (!ht_empty(root_ht))
599 return false;
600 }
601 }
602
603 if (tp_c->refcnt > 1)
604 return false;
605
606 if (tp_c->refcnt == 1) {
607 struct tc_u_hnode *ht;
608
609 for (ht = rtnl_dereference(tp_c->hlist);
610 ht;
611 ht = rtnl_dereference(ht->next))
612 if (!ht_empty(ht))
613 return false;
614 }
615 }
616
617 if (root_ht && --root_ht->refcnt == 0)
618 u32_destroy_hnode(tp, root_ht);
619
620 if (--tp_c->refcnt == 0) {
621 struct tc_u_hnode *ht;
622
623 tp->q->u32_node = NULL;
624
625 for (ht = rtnl_dereference(tp_c->hlist);
626 ht;
627 ht = rtnl_dereference(ht->next)) {
628 ht->refcnt--;
629 u32_clear_hnode(tp, ht);
630 }
631
632 while ((ht = rtnl_dereference(tp_c->hlist)) != NULL) {
633 RCU_INIT_POINTER(tp_c->hlist, ht->next);
634 kfree_rcu(ht, rcu);
635 }
636
637 kfree(tp_c);
638 }
639
640 tp->data = NULL;
641 return true;
642 }
643
u32_delete(struct tcf_proto * tp,unsigned long arg)644 static int u32_delete(struct tcf_proto *tp, unsigned long arg)
645 {
646 struct tc_u_hnode *ht = (struct tc_u_hnode *)arg;
647 struct tc_u_hnode *root_ht = rtnl_dereference(tp->root);
648
649 if (ht == NULL)
650 return 0;
651
652 if (TC_U32_KEY(ht->handle)) {
653 u32_remove_hw_knode(tp, ht->handle);
654 return u32_delete_key(tp, (struct tc_u_knode *)ht);
655 }
656
657 if (root_ht == ht)
658 return -EINVAL;
659
660 if (ht->refcnt == 1) {
661 ht->refcnt--;
662 u32_destroy_hnode(tp, ht);
663 } else {
664 return -EBUSY;
665 }
666
667 return 0;
668 }
669
670 #define NR_U32_NODE (1<<12)
gen_new_kid(struct tc_u_hnode * ht,u32 handle)671 static u32 gen_new_kid(struct tc_u_hnode *ht, u32 handle)
672 {
673 struct tc_u_knode *n;
674 unsigned long i;
675 unsigned long *bitmap = kzalloc(BITS_TO_LONGS(NR_U32_NODE) * sizeof(unsigned long),
676 GFP_KERNEL);
677 if (!bitmap)
678 return handle | 0xFFF;
679
680 for (n = rtnl_dereference(ht->ht[TC_U32_HASH(handle)]);
681 n;
682 n = rtnl_dereference(n->next))
683 set_bit(TC_U32_NODE(n->handle), bitmap);
684
685 i = find_next_zero_bit(bitmap, NR_U32_NODE, 0x800);
686 if (i >= NR_U32_NODE)
687 i = find_next_zero_bit(bitmap, NR_U32_NODE, 1);
688
689 kfree(bitmap);
690 return handle | (i >= NR_U32_NODE ? 0xFFF : i);
691 }
692
693 static const struct nla_policy u32_policy[TCA_U32_MAX + 1] = {
694 [TCA_U32_CLASSID] = { .type = NLA_U32 },
695 [TCA_U32_HASH] = { .type = NLA_U32 },
696 [TCA_U32_LINK] = { .type = NLA_U32 },
697 [TCA_U32_DIVISOR] = { .type = NLA_U32 },
698 [TCA_U32_SEL] = { .len = sizeof(struct tc_u32_sel) },
699 [TCA_U32_INDEV] = { .type = NLA_STRING, .len = IFNAMSIZ },
700 [TCA_U32_MARK] = { .len = sizeof(struct tc_u32_mark) },
701 [TCA_U32_FLAGS] = { .type = NLA_U32 },
702 };
703
u32_set_parms(struct net * net,struct tcf_proto * tp,unsigned long base,struct tc_u_hnode * ht,struct tc_u_knode * n,struct nlattr ** tb,struct nlattr * est,bool ovr)704 static int u32_set_parms(struct net *net, struct tcf_proto *tp,
705 unsigned long base, struct tc_u_hnode *ht,
706 struct tc_u_knode *n, struct nlattr **tb,
707 struct nlattr *est, bool ovr)
708 {
709 struct tcf_exts e;
710 int err;
711
712 err = tcf_exts_init(&e, TCA_U32_ACT, TCA_U32_POLICE);
713 if (err < 0)
714 return err;
715 err = tcf_exts_validate(net, tp, tb, est, &e, ovr);
716 if (err < 0)
717 goto errout;
718
719 err = -EINVAL;
720 if (tb[TCA_U32_LINK]) {
721 u32 handle = nla_get_u32(tb[TCA_U32_LINK]);
722 struct tc_u_hnode *ht_down = NULL, *ht_old;
723
724 if (TC_U32_KEY(handle))
725 goto errout;
726
727 if (handle) {
728 ht_down = u32_lookup_ht(ht->tp_c, handle);
729
730 if (ht_down == NULL)
731 goto errout;
732 ht_down->refcnt++;
733 }
734
735 ht_old = rtnl_dereference(n->ht_down);
736 rcu_assign_pointer(n->ht_down, ht_down);
737
738 if (ht_old)
739 ht_old->refcnt--;
740 }
741 if (tb[TCA_U32_CLASSID]) {
742 n->res.classid = nla_get_u32(tb[TCA_U32_CLASSID]);
743 tcf_bind_filter(tp, &n->res, base);
744 }
745
746 #ifdef CONFIG_NET_CLS_IND
747 if (tb[TCA_U32_INDEV]) {
748 int ret;
749 ret = tcf_change_indev(net, tb[TCA_U32_INDEV]);
750 if (ret < 0)
751 goto errout;
752 n->ifindex = ret;
753 }
754 #endif
755 tcf_exts_change(tp, &n->exts, &e);
756
757 return 0;
758 errout:
759 tcf_exts_destroy(&e);
760 return err;
761 }
762
u32_replace_knode(struct tcf_proto * tp,struct tc_u_common * tp_c,struct tc_u_knode * n)763 static void u32_replace_knode(struct tcf_proto *tp, struct tc_u_common *tp_c,
764 struct tc_u_knode *n)
765 {
766 struct tc_u_knode __rcu **ins;
767 struct tc_u_knode *pins;
768 struct tc_u_hnode *ht;
769
770 if (TC_U32_HTID(n->handle) == TC_U32_ROOT)
771 ht = rtnl_dereference(tp->root);
772 else
773 ht = u32_lookup_ht(tp_c, TC_U32_HTID(n->handle));
774
775 ins = &ht->ht[TC_U32_HASH(n->handle)];
776
777 /* The node must always exist for it to be replaced if this is not the
778 * case then something went very wrong elsewhere.
779 */
780 for (pins = rtnl_dereference(*ins); ;
781 ins = &pins->next, pins = rtnl_dereference(*ins))
782 if (pins->handle == n->handle)
783 break;
784
785 RCU_INIT_POINTER(n->next, pins->next);
786 rcu_assign_pointer(*ins, n);
787 }
788
u32_init_knode(struct tcf_proto * tp,struct tc_u_knode * n)789 static struct tc_u_knode *u32_init_knode(struct tcf_proto *tp,
790 struct tc_u_knode *n)
791 {
792 struct tc_u_hnode *ht = rtnl_dereference(n->ht_down);
793 struct tc_u32_sel *s = &n->sel;
794 struct tc_u_knode *new;
795
796 new = kzalloc(sizeof(*n) + s->nkeys*sizeof(struct tc_u32_key),
797 GFP_KERNEL);
798
799 if (!new)
800 return NULL;
801
802 RCU_INIT_POINTER(new->next, n->next);
803 new->handle = n->handle;
804 RCU_INIT_POINTER(new->ht_up, n->ht_up);
805
806 #ifdef CONFIG_NET_CLS_IND
807 new->ifindex = n->ifindex;
808 #endif
809 new->fshift = n->fshift;
810 new->res = n->res;
811 new->flags = n->flags;
812 RCU_INIT_POINTER(new->ht_down, ht);
813
814 /* bump reference count as long as we hold pointer to structure */
815 if (ht)
816 ht->refcnt++;
817
818 #ifdef CONFIG_CLS_U32_PERF
819 /* Statistics may be incremented by readers during update
820 * so we must keep them in tact. When the node is later destroyed
821 * a special destroy call must be made to not free the pf memory.
822 */
823 new->pf = n->pf;
824 #endif
825
826 #ifdef CONFIG_CLS_U32_MARK
827 new->val = n->val;
828 new->mask = n->mask;
829 /* Similarly success statistics must be moved as pointers */
830 new->pcpu_success = n->pcpu_success;
831 #endif
832 new->tp = tp;
833 memcpy(&new->sel, s, sizeof(*s) + s->nkeys*sizeof(struct tc_u32_key));
834
835 if (tcf_exts_init(&new->exts, TCA_U32_ACT, TCA_U32_POLICE)) {
836 kfree(new);
837 return NULL;
838 }
839
840 return new;
841 }
842
u32_change(struct net * net,struct sk_buff * in_skb,struct tcf_proto * tp,unsigned long base,u32 handle,struct nlattr ** tca,unsigned long * arg,bool ovr)843 static int u32_change(struct net *net, struct sk_buff *in_skb,
844 struct tcf_proto *tp, unsigned long base, u32 handle,
845 struct nlattr **tca, unsigned long *arg, bool ovr)
846 {
847 struct tc_u_common *tp_c = tp->data;
848 struct tc_u_hnode *ht;
849 struct tc_u_knode *n;
850 struct tc_u32_sel *s;
851 struct nlattr *opt = tca[TCA_OPTIONS];
852 struct nlattr *tb[TCA_U32_MAX + 1];
853 u32 htid, flags = 0;
854 int err;
855 #ifdef CONFIG_CLS_U32_PERF
856 size_t size;
857 #endif
858
859 if (opt == NULL)
860 return handle ? -EINVAL : 0;
861
862 err = nla_parse_nested(tb, TCA_U32_MAX, opt, u32_policy);
863 if (err < 0)
864 return err;
865
866 if (tb[TCA_U32_FLAGS]) {
867 flags = nla_get_u32(tb[TCA_U32_FLAGS]);
868 if (!tc_flags_valid(flags))
869 return -EINVAL;
870 }
871
872 n = (struct tc_u_knode *)*arg;
873 if (n) {
874 struct tc_u_knode *new;
875
876 if (TC_U32_KEY(n->handle) == 0)
877 return -EINVAL;
878
879 if (n->flags != flags)
880 return -EINVAL;
881
882 new = u32_init_knode(tp, n);
883 if (!new)
884 return -ENOMEM;
885
886 err = u32_set_parms(net, tp, base,
887 rtnl_dereference(n->ht_up), new, tb,
888 tca[TCA_RATE], ovr);
889
890 if (err) {
891 u32_destroy_key(tp, new, false);
892 return err;
893 }
894
895 err = u32_replace_hw_knode(tp, new, flags);
896 if (err) {
897 u32_destroy_key(tp, new, false);
898 return err;
899 }
900
901 u32_replace_knode(tp, tp_c, new);
902 tcf_unbind_filter(tp, &n->res);
903 call_rcu(&n->rcu, u32_delete_key_rcu);
904 return 0;
905 }
906
907 if (tb[TCA_U32_DIVISOR]) {
908 unsigned int divisor = nla_get_u32(tb[TCA_U32_DIVISOR]);
909
910 if (--divisor > 0x100)
911 return -EINVAL;
912 if (TC_U32_KEY(handle))
913 return -EINVAL;
914 if (handle == 0) {
915 handle = gen_new_htid(tp->data);
916 if (handle == 0)
917 return -ENOMEM;
918 }
919 ht = kzalloc(sizeof(*ht) + divisor*sizeof(void *), GFP_KERNEL);
920 if (ht == NULL)
921 return -ENOBUFS;
922 ht->tp_c = tp_c;
923 ht->refcnt = 1;
924 ht->divisor = divisor;
925 ht->handle = handle;
926 ht->prio = tp->prio;
927
928 err = u32_replace_hw_hnode(tp, ht, flags);
929 if (err) {
930 kfree(ht);
931 return err;
932 }
933
934 RCU_INIT_POINTER(ht->next, tp_c->hlist);
935 rcu_assign_pointer(tp_c->hlist, ht);
936 *arg = (unsigned long)ht;
937
938 return 0;
939 }
940
941 if (tb[TCA_U32_HASH]) {
942 htid = nla_get_u32(tb[TCA_U32_HASH]);
943 if (TC_U32_HTID(htid) == TC_U32_ROOT) {
944 ht = rtnl_dereference(tp->root);
945 htid = ht->handle;
946 } else {
947 ht = u32_lookup_ht(tp->data, TC_U32_HTID(htid));
948 if (ht == NULL)
949 return -EINVAL;
950 }
951 } else {
952 ht = rtnl_dereference(tp->root);
953 htid = ht->handle;
954 }
955
956 if (ht->divisor < TC_U32_HASH(htid))
957 return -EINVAL;
958
959 if (handle) {
960 if (TC_U32_HTID(handle) && TC_U32_HTID(handle^htid))
961 return -EINVAL;
962 handle = htid | TC_U32_NODE(handle);
963 } else
964 handle = gen_new_kid(ht, htid);
965
966 if (tb[TCA_U32_SEL] == NULL)
967 return -EINVAL;
968
969 s = nla_data(tb[TCA_U32_SEL]);
970
971 n = kzalloc(sizeof(*n) + s->nkeys*sizeof(struct tc_u32_key), GFP_KERNEL);
972 if (n == NULL)
973 return -ENOBUFS;
974
975 #ifdef CONFIG_CLS_U32_PERF
976 size = sizeof(struct tc_u32_pcnt) + s->nkeys * sizeof(u64);
977 n->pf = __alloc_percpu(size, __alignof__(struct tc_u32_pcnt));
978 if (!n->pf) {
979 kfree(n);
980 return -ENOBUFS;
981 }
982 #endif
983
984 memcpy(&n->sel, s, sizeof(*s) + s->nkeys*sizeof(struct tc_u32_key));
985 RCU_INIT_POINTER(n->ht_up, ht);
986 n->handle = handle;
987 n->fshift = s->hmask ? ffs(ntohl(s->hmask)) - 1 : 0;
988 n->flags = flags;
989 n->tp = tp;
990
991 err = tcf_exts_init(&n->exts, TCA_U32_ACT, TCA_U32_POLICE);
992 if (err < 0)
993 goto errout;
994
995 #ifdef CONFIG_CLS_U32_MARK
996 n->pcpu_success = alloc_percpu(u32);
997 if (!n->pcpu_success) {
998 err = -ENOMEM;
999 goto errout;
1000 }
1001
1002 if (tb[TCA_U32_MARK]) {
1003 struct tc_u32_mark *mark;
1004
1005 mark = nla_data(tb[TCA_U32_MARK]);
1006 n->val = mark->val;
1007 n->mask = mark->mask;
1008 }
1009 #endif
1010
1011 err = u32_set_parms(net, tp, base, ht, n, tb, tca[TCA_RATE], ovr);
1012 if (err == 0) {
1013 struct tc_u_knode __rcu **ins;
1014 struct tc_u_knode *pins;
1015
1016 err = u32_replace_hw_knode(tp, n, flags);
1017 if (err)
1018 goto errhw;
1019
1020 ins = &ht->ht[TC_U32_HASH(handle)];
1021 for (pins = rtnl_dereference(*ins); pins;
1022 ins = &pins->next, pins = rtnl_dereference(*ins))
1023 if (TC_U32_NODE(handle) < TC_U32_NODE(pins->handle))
1024 break;
1025
1026 RCU_INIT_POINTER(n->next, pins);
1027 rcu_assign_pointer(*ins, n);
1028 *arg = (unsigned long)n;
1029 return 0;
1030 }
1031
1032 errhw:
1033 #ifdef CONFIG_CLS_U32_MARK
1034 free_percpu(n->pcpu_success);
1035 #endif
1036
1037 errout:
1038 tcf_exts_destroy(&n->exts);
1039 #ifdef CONFIG_CLS_U32_PERF
1040 free_percpu(n->pf);
1041 #endif
1042 kfree(n);
1043 return err;
1044 }
1045
u32_walk(struct tcf_proto * tp,struct tcf_walker * arg)1046 static void u32_walk(struct tcf_proto *tp, struct tcf_walker *arg)
1047 {
1048 struct tc_u_common *tp_c = tp->data;
1049 struct tc_u_hnode *ht;
1050 struct tc_u_knode *n;
1051 unsigned int h;
1052
1053 if (arg->stop)
1054 return;
1055
1056 for (ht = rtnl_dereference(tp_c->hlist);
1057 ht;
1058 ht = rtnl_dereference(ht->next)) {
1059 if (ht->prio != tp->prio)
1060 continue;
1061 if (arg->count >= arg->skip) {
1062 if (arg->fn(tp, (unsigned long)ht, arg) < 0) {
1063 arg->stop = 1;
1064 return;
1065 }
1066 }
1067 arg->count++;
1068 for (h = 0; h <= ht->divisor; h++) {
1069 for (n = rtnl_dereference(ht->ht[h]);
1070 n;
1071 n = rtnl_dereference(n->next)) {
1072 if (arg->count < arg->skip) {
1073 arg->count++;
1074 continue;
1075 }
1076 if (arg->fn(tp, (unsigned long)n, arg) < 0) {
1077 arg->stop = 1;
1078 return;
1079 }
1080 arg->count++;
1081 }
1082 }
1083 }
1084 }
1085
u32_dump(struct net * net,struct tcf_proto * tp,unsigned long fh,struct sk_buff * skb,struct tcmsg * t)1086 static int u32_dump(struct net *net, struct tcf_proto *tp, unsigned long fh,
1087 struct sk_buff *skb, struct tcmsg *t)
1088 {
1089 struct tc_u_knode *n = (struct tc_u_knode *)fh;
1090 struct tc_u_hnode *ht_up, *ht_down;
1091 struct nlattr *nest;
1092
1093 if (n == NULL)
1094 return skb->len;
1095
1096 t->tcm_handle = n->handle;
1097
1098 nest = nla_nest_start(skb, TCA_OPTIONS);
1099 if (nest == NULL)
1100 goto nla_put_failure;
1101
1102 if (TC_U32_KEY(n->handle) == 0) {
1103 struct tc_u_hnode *ht = (struct tc_u_hnode *)fh;
1104 u32 divisor = ht->divisor + 1;
1105
1106 if (nla_put_u32(skb, TCA_U32_DIVISOR, divisor))
1107 goto nla_put_failure;
1108 } else {
1109 #ifdef CONFIG_CLS_U32_PERF
1110 struct tc_u32_pcnt *gpf;
1111 int cpu;
1112 #endif
1113
1114 if (nla_put(skb, TCA_U32_SEL,
1115 sizeof(n->sel) + n->sel.nkeys*sizeof(struct tc_u32_key),
1116 &n->sel))
1117 goto nla_put_failure;
1118
1119 ht_up = rtnl_dereference(n->ht_up);
1120 if (ht_up) {
1121 u32 htid = n->handle & 0xFFFFF000;
1122 if (nla_put_u32(skb, TCA_U32_HASH, htid))
1123 goto nla_put_failure;
1124 }
1125 if (n->res.classid &&
1126 nla_put_u32(skb, TCA_U32_CLASSID, n->res.classid))
1127 goto nla_put_failure;
1128
1129 ht_down = rtnl_dereference(n->ht_down);
1130 if (ht_down &&
1131 nla_put_u32(skb, TCA_U32_LINK, ht_down->handle))
1132 goto nla_put_failure;
1133
1134 if (n->flags && nla_put_u32(skb, TCA_U32_FLAGS, n->flags))
1135 goto nla_put_failure;
1136
1137 #ifdef CONFIG_CLS_U32_MARK
1138 if ((n->val || n->mask)) {
1139 struct tc_u32_mark mark = {.val = n->val,
1140 .mask = n->mask,
1141 .success = 0};
1142 int cpum;
1143
1144 for_each_possible_cpu(cpum) {
1145 __u32 cnt = *per_cpu_ptr(n->pcpu_success, cpum);
1146
1147 mark.success += cnt;
1148 }
1149
1150 if (nla_put(skb, TCA_U32_MARK, sizeof(mark), &mark))
1151 goto nla_put_failure;
1152 }
1153 #endif
1154
1155 if (tcf_exts_dump(skb, &n->exts) < 0)
1156 goto nla_put_failure;
1157
1158 #ifdef CONFIG_NET_CLS_IND
1159 if (n->ifindex) {
1160 struct net_device *dev;
1161 dev = __dev_get_by_index(net, n->ifindex);
1162 if (dev && nla_put_string(skb, TCA_U32_INDEV, dev->name))
1163 goto nla_put_failure;
1164 }
1165 #endif
1166 #ifdef CONFIG_CLS_U32_PERF
1167 gpf = kzalloc(sizeof(struct tc_u32_pcnt) +
1168 n->sel.nkeys * sizeof(u64),
1169 GFP_KERNEL);
1170 if (!gpf)
1171 goto nla_put_failure;
1172
1173 for_each_possible_cpu(cpu) {
1174 int i;
1175 struct tc_u32_pcnt *pf = per_cpu_ptr(n->pf, cpu);
1176
1177 gpf->rcnt += pf->rcnt;
1178 gpf->rhit += pf->rhit;
1179 for (i = 0; i < n->sel.nkeys; i++)
1180 gpf->kcnts[i] += pf->kcnts[i];
1181 }
1182
1183 if (nla_put_64bit(skb, TCA_U32_PCNT,
1184 sizeof(struct tc_u32_pcnt) +
1185 n->sel.nkeys * sizeof(u64),
1186 gpf, TCA_U32_PAD)) {
1187 kfree(gpf);
1188 goto nla_put_failure;
1189 }
1190 kfree(gpf);
1191 #endif
1192 }
1193
1194 nla_nest_end(skb, nest);
1195
1196 if (TC_U32_KEY(n->handle))
1197 if (tcf_exts_dump_stats(skb, &n->exts) < 0)
1198 goto nla_put_failure;
1199 return skb->len;
1200
1201 nla_put_failure:
1202 nla_nest_cancel(skb, nest);
1203 return -1;
1204 }
1205
1206 static struct tcf_proto_ops cls_u32_ops __read_mostly = {
1207 .kind = "u32",
1208 .classify = u32_classify,
1209 .init = u32_init,
1210 .destroy = u32_destroy,
1211 .get = u32_get,
1212 .change = u32_change,
1213 .delete = u32_delete,
1214 .walk = u32_walk,
1215 .dump = u32_dump,
1216 .owner = THIS_MODULE,
1217 };
1218
init_u32(void)1219 static int __init init_u32(void)
1220 {
1221 pr_info("u32 classifier\n");
1222 #ifdef CONFIG_CLS_U32_PERF
1223 pr_info(" Performance counters on\n");
1224 #endif
1225 #ifdef CONFIG_NET_CLS_IND
1226 pr_info(" input device check on\n");
1227 #endif
1228 #ifdef CONFIG_NET_CLS_ACT
1229 pr_info(" Actions configured\n");
1230 #endif
1231 return register_tcf_proto_ops(&cls_u32_ops);
1232 }
1233
exit_u32(void)1234 static void __exit exit_u32(void)
1235 {
1236 unregister_tcf_proto_ops(&cls_u32_ops);
1237 }
1238
1239 module_init(init_u32)
1240 module_exit(exit_u32)
1241 MODULE_LICENSE("GPL");
1242