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 <linux/netdevice.h>
44 #include <linux/hash.h>
45 #include <net/netlink.h>
46 #include <net/act_api.h>
47 #include <net/pkt_cls.h>
48 #include <linux/netdevice.h>
49
50 struct tc_u_knode {
51 struct tc_u_knode __rcu *next;
52 u32 handle;
53 struct tc_u_hnode __rcu *ht_up;
54 struct tcf_exts exts;
55 #ifdef CONFIG_NET_CLS_IND
56 int ifindex;
57 #endif
58 u8 fshift;
59 struct tcf_result res;
60 struct tc_u_hnode __rcu *ht_down;
61 #ifdef CONFIG_CLS_U32_PERF
62 struct tc_u32_pcnt __percpu *pf;
63 #endif
64 u32 flags;
65 #ifdef CONFIG_CLS_U32_MARK
66 u32 val;
67 u32 mask;
68 u32 __percpu *pcpu_success;
69 #endif
70 struct tcf_proto *tp;
71 union {
72 struct work_struct work;
73 struct rcu_head rcu;
74 };
75 /* The 'sel' field MUST be the last field in structure to allow for
76 * tc_u32_keys allocated at end of structure.
77 */
78 struct tc_u32_sel sel;
79 };
80
81 struct tc_u_hnode {
82 struct tc_u_hnode __rcu *next;
83 u32 handle;
84 u32 prio;
85 struct tc_u_common *tp_c;
86 int refcnt;
87 unsigned int divisor;
88 struct rcu_head rcu;
89 /* The 'ht' field MUST be the last field in structure to allow for
90 * more entries allocated at end of structure.
91 */
92 struct tc_u_knode __rcu *ht[1];
93 };
94
95 struct tc_u_common {
96 struct tc_u_hnode __rcu *hlist;
97 struct Qdisc *q;
98 int refcnt;
99 u32 hgenerator;
100 struct hlist_node hnode;
101 struct rcu_head rcu;
102 };
103
u32_hash_fold(__be32 key,const struct tc_u32_sel * sel,u8 fshift)104 static inline unsigned int u32_hash_fold(__be32 key,
105 const struct tc_u32_sel *sel,
106 u8 fshift)
107 {
108 unsigned int h = ntohl(key & sel->hmask) >> fshift;
109
110 return h;
111 }
112
u32_classify(struct sk_buff * skb,const struct tcf_proto * tp,struct tcf_result * res)113 static int u32_classify(struct sk_buff *skb, const struct tcf_proto *tp,
114 struct tcf_result *res)
115 {
116 struct {
117 struct tc_u_knode *knode;
118 unsigned int off;
119 } stack[TC_U32_MAXDEPTH];
120
121 struct tc_u_hnode *ht = rcu_dereference_bh(tp->root);
122 unsigned int off = skb_network_offset(skb);
123 struct tc_u_knode *n;
124 int sdepth = 0;
125 int off2 = 0;
126 int sel = 0;
127 #ifdef CONFIG_CLS_U32_PERF
128 int j;
129 #endif
130 int i, r;
131
132 next_ht:
133 n = rcu_dereference_bh(ht->ht[sel]);
134
135 next_knode:
136 if (n) {
137 struct tc_u32_key *key = n->sel.keys;
138
139 #ifdef CONFIG_CLS_U32_PERF
140 __this_cpu_inc(n->pf->rcnt);
141 j = 0;
142 #endif
143
144 if (tc_skip_sw(n->flags)) {
145 n = rcu_dereference_bh(n->next);
146 goto next_knode;
147 }
148
149 #ifdef CONFIG_CLS_U32_MARK
150 if ((skb->mark & n->mask) != n->val) {
151 n = rcu_dereference_bh(n->next);
152 goto next_knode;
153 } else {
154 __this_cpu_inc(*n->pcpu_success);
155 }
156 #endif
157
158 for (i = n->sel.nkeys; i > 0; i--, key++) {
159 int toff = off + key->off + (off2 & key->offmask);
160 __be32 *data, hdata;
161
162 if (skb_headroom(skb) + toff > INT_MAX)
163 goto out;
164
165 data = skb_header_pointer(skb, toff, 4, &hdata);
166 if (!data)
167 goto out;
168 if ((*data ^ key->val) & key->mask) {
169 n = rcu_dereference_bh(n->next);
170 goto next_knode;
171 }
172 #ifdef CONFIG_CLS_U32_PERF
173 __this_cpu_inc(n->pf->kcnts[j]);
174 j++;
175 #endif
176 }
177
178 ht = rcu_dereference_bh(n->ht_down);
179 if (!ht) {
180 check_terminal:
181 if (n->sel.flags & TC_U32_TERMINAL) {
182
183 *res = n->res;
184 #ifdef CONFIG_NET_CLS_IND
185 if (!tcf_match_indev(skb, n->ifindex)) {
186 n = rcu_dereference_bh(n->next);
187 goto next_knode;
188 }
189 #endif
190 #ifdef CONFIG_CLS_U32_PERF
191 __this_cpu_inc(n->pf->rhit);
192 #endif
193 r = tcf_exts_exec(skb, &n->exts, res);
194 if (r < 0) {
195 n = rcu_dereference_bh(n->next);
196 goto next_knode;
197 }
198
199 return r;
200 }
201 n = rcu_dereference_bh(n->next);
202 goto next_knode;
203 }
204
205 /* PUSH */
206 if (sdepth >= TC_U32_MAXDEPTH)
207 goto deadloop;
208 stack[sdepth].knode = n;
209 stack[sdepth].off = off;
210 sdepth++;
211
212 ht = rcu_dereference_bh(n->ht_down);
213 sel = 0;
214 if (ht->divisor) {
215 __be32 *data, hdata;
216
217 data = skb_header_pointer(skb, off + n->sel.hoff, 4,
218 &hdata);
219 if (!data)
220 goto out;
221 sel = ht->divisor & u32_hash_fold(*data, &n->sel,
222 n->fshift);
223 }
224 if (!(n->sel.flags & (TC_U32_VAROFFSET | TC_U32_OFFSET | TC_U32_EAT)))
225 goto next_ht;
226
227 if (n->sel.flags & (TC_U32_OFFSET | TC_U32_VAROFFSET)) {
228 off2 = n->sel.off + 3;
229 if (n->sel.flags & TC_U32_VAROFFSET) {
230 __be16 *data, hdata;
231
232 data = skb_header_pointer(skb,
233 off + n->sel.offoff,
234 2, &hdata);
235 if (!data)
236 goto out;
237 off2 += ntohs(n->sel.offmask & *data) >>
238 n->sel.offshift;
239 }
240 off2 &= ~3;
241 }
242 if (n->sel.flags & TC_U32_EAT) {
243 off += off2;
244 off2 = 0;
245 }
246
247 if (off < skb->len)
248 goto next_ht;
249 }
250
251 /* POP */
252 if (sdepth--) {
253 n = stack[sdepth].knode;
254 ht = rcu_dereference_bh(n->ht_up);
255 off = stack[sdepth].off;
256 goto check_terminal;
257 }
258 out:
259 return -1;
260
261 deadloop:
262 net_warn_ratelimited("cls_u32: dead loop\n");
263 return -1;
264 }
265
u32_lookup_ht(struct tc_u_common * tp_c,u32 handle)266 static struct tc_u_hnode *u32_lookup_ht(struct tc_u_common *tp_c, u32 handle)
267 {
268 struct tc_u_hnode *ht;
269
270 for (ht = rtnl_dereference(tp_c->hlist);
271 ht;
272 ht = rtnl_dereference(ht->next))
273 if (ht->handle == handle)
274 break;
275
276 return ht;
277 }
278
u32_lookup_key(struct tc_u_hnode * ht,u32 handle)279 static struct tc_u_knode *u32_lookup_key(struct tc_u_hnode *ht, u32 handle)
280 {
281 unsigned int sel;
282 struct tc_u_knode *n = NULL;
283
284 sel = TC_U32_HASH(handle);
285 if (sel > ht->divisor)
286 goto out;
287
288 for (n = rtnl_dereference(ht->ht[sel]);
289 n;
290 n = rtnl_dereference(n->next))
291 if (n->handle == handle)
292 break;
293 out:
294 return n;
295 }
296
297
u32_get(struct tcf_proto * tp,u32 handle)298 static void *u32_get(struct tcf_proto *tp, u32 handle)
299 {
300 struct tc_u_hnode *ht;
301 struct tc_u_common *tp_c = tp->data;
302
303 if (TC_U32_HTID(handle) == TC_U32_ROOT)
304 ht = rtnl_dereference(tp->root);
305 else
306 ht = u32_lookup_ht(tp_c, TC_U32_HTID(handle));
307
308 if (!ht)
309 return NULL;
310
311 if (TC_U32_KEY(handle) == 0)
312 return ht;
313
314 return u32_lookup_key(ht, handle);
315 }
316
gen_new_htid(struct tc_u_common * tp_c)317 static u32 gen_new_htid(struct tc_u_common *tp_c)
318 {
319 int i = 0x800;
320
321 /* hgenerator only used inside rtnl lock it is safe to increment
322 * without read _copy_ update semantics
323 */
324 do {
325 if (++tp_c->hgenerator == 0x7FF)
326 tp_c->hgenerator = 1;
327 } while (--i > 0 && u32_lookup_ht(tp_c, (tp_c->hgenerator|0x800)<<20));
328
329 return i > 0 ? (tp_c->hgenerator|0x800)<<20 : 0;
330 }
331
332 static struct hlist_head *tc_u_common_hash;
333
334 #define U32_HASH_SHIFT 10
335 #define U32_HASH_SIZE (1 << U32_HASH_SHIFT)
336
tc_u_hash(const struct tcf_proto * tp)337 static unsigned int tc_u_hash(const struct tcf_proto *tp)
338 {
339 struct net_device *dev = tp->q->dev_queue->dev;
340 u32 qhandle = tp->q->handle;
341 int ifindex = dev->ifindex;
342
343 return hash_64((u64)ifindex << 32 | qhandle, U32_HASH_SHIFT);
344 }
345
tc_u_common_find(const struct tcf_proto * tp)346 static struct tc_u_common *tc_u_common_find(const struct tcf_proto *tp)
347 {
348 struct tc_u_common *tc;
349 unsigned int h;
350
351 h = tc_u_hash(tp);
352 hlist_for_each_entry(tc, &tc_u_common_hash[h], hnode) {
353 if (tc->q == tp->q)
354 return tc;
355 }
356 return NULL;
357 }
358
u32_init(struct tcf_proto * tp)359 static int u32_init(struct tcf_proto *tp)
360 {
361 struct tc_u_hnode *root_ht;
362 struct tc_u_common *tp_c;
363 unsigned int h;
364
365 tp_c = tc_u_common_find(tp);
366
367 root_ht = kzalloc(sizeof(*root_ht), GFP_KERNEL);
368 if (root_ht == NULL)
369 return -ENOBUFS;
370
371 root_ht->refcnt++;
372 root_ht->handle = tp_c ? gen_new_htid(tp_c) : 0x80000000;
373 root_ht->prio = tp->prio;
374
375 if (tp_c == NULL) {
376 tp_c = kzalloc(sizeof(*tp_c), GFP_KERNEL);
377 if (tp_c == NULL) {
378 kfree(root_ht);
379 return -ENOBUFS;
380 }
381 tp_c->q = tp->q;
382 INIT_HLIST_NODE(&tp_c->hnode);
383
384 h = tc_u_hash(tp);
385 hlist_add_head(&tp_c->hnode, &tc_u_common_hash[h]);
386 }
387
388 tp_c->refcnt++;
389 RCU_INIT_POINTER(root_ht->next, tp_c->hlist);
390 rcu_assign_pointer(tp_c->hlist, root_ht);
391 root_ht->tp_c = tp_c;
392
393 rcu_assign_pointer(tp->root, root_ht);
394 tp->data = tp_c;
395 return 0;
396 }
397
u32_destroy_key(struct tcf_proto * tp,struct tc_u_knode * n,bool free_pf)398 static int u32_destroy_key(struct tcf_proto *tp, struct tc_u_knode *n,
399 bool free_pf)
400 {
401 struct tc_u_hnode *ht = rtnl_dereference(n->ht_down);
402
403 tcf_exts_destroy(&n->exts);
404 tcf_exts_put_net(&n->exts);
405 if (ht && --ht->refcnt == 0)
406 kfree(ht);
407 #ifdef CONFIG_CLS_U32_PERF
408 if (free_pf)
409 free_percpu(n->pf);
410 #endif
411 #ifdef CONFIG_CLS_U32_MARK
412 if (free_pf)
413 free_percpu(n->pcpu_success);
414 #endif
415 kfree(n);
416 return 0;
417 }
418
419 /* u32_delete_key_rcu should be called when free'ing a copied
420 * version of a tc_u_knode obtained from u32_init_knode(). When
421 * copies are obtained from u32_init_knode() the statistics are
422 * shared between the old and new copies to allow readers to
423 * continue to update the statistics during the copy. To support
424 * this the u32_delete_key_rcu variant does not free the percpu
425 * statistics.
426 */
u32_delete_key_work(struct work_struct * work)427 static void u32_delete_key_work(struct work_struct *work)
428 {
429 struct tc_u_knode *key = container_of(work, struct tc_u_knode, work);
430
431 rtnl_lock();
432 u32_destroy_key(key->tp, key, false);
433 rtnl_unlock();
434 }
435
u32_delete_key_rcu(struct rcu_head * rcu)436 static void u32_delete_key_rcu(struct rcu_head *rcu)
437 {
438 struct tc_u_knode *key = container_of(rcu, struct tc_u_knode, rcu);
439
440 INIT_WORK(&key->work, u32_delete_key_work);
441 tcf_queue_work(&key->work);
442 }
443
444 /* u32_delete_key_freepf_rcu is the rcu callback variant
445 * that free's the entire structure including the statistics
446 * percpu variables. Only use this if the key is not a copy
447 * returned by u32_init_knode(). See u32_delete_key_rcu()
448 * for the variant that should be used with keys return from
449 * u32_init_knode()
450 */
u32_delete_key_freepf_work(struct work_struct * work)451 static void u32_delete_key_freepf_work(struct work_struct *work)
452 {
453 struct tc_u_knode *key = container_of(work, struct tc_u_knode, work);
454
455 rtnl_lock();
456 u32_destroy_key(key->tp, key, true);
457 rtnl_unlock();
458 }
459
u32_delete_key_freepf_rcu(struct rcu_head * rcu)460 static void u32_delete_key_freepf_rcu(struct rcu_head *rcu)
461 {
462 struct tc_u_knode *key = container_of(rcu, struct tc_u_knode, rcu);
463
464 INIT_WORK(&key->work, u32_delete_key_freepf_work);
465 tcf_queue_work(&key->work);
466 }
467
u32_delete_key(struct tcf_proto * tp,struct tc_u_knode * key)468 static int u32_delete_key(struct tcf_proto *tp, struct tc_u_knode *key)
469 {
470 struct tc_u_knode __rcu **kp;
471 struct tc_u_knode *pkp;
472 struct tc_u_hnode *ht = rtnl_dereference(key->ht_up);
473
474 if (ht) {
475 kp = &ht->ht[TC_U32_HASH(key->handle)];
476 for (pkp = rtnl_dereference(*kp); pkp;
477 kp = &pkp->next, pkp = rtnl_dereference(*kp)) {
478 if (pkp == key) {
479 RCU_INIT_POINTER(*kp, key->next);
480
481 tcf_unbind_filter(tp, &key->res);
482 tcf_exts_get_net(&key->exts);
483 call_rcu(&key->rcu, u32_delete_key_freepf_rcu);
484 return 0;
485 }
486 }
487 }
488 WARN_ON(1);
489 return 0;
490 }
491
u32_remove_hw_knode(struct tcf_proto * tp,u32 handle)492 static void u32_remove_hw_knode(struct tcf_proto *tp, u32 handle)
493 {
494 struct net_device *dev = tp->q->dev_queue->dev;
495 struct tc_cls_u32_offload cls_u32 = {};
496
497 if (!tc_should_offload(dev, 0))
498 return;
499
500 tc_cls_common_offload_init(&cls_u32.common, tp);
501 cls_u32.command = TC_CLSU32_DELETE_KNODE;
502 cls_u32.knode.handle = handle;
503
504 dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_CLSU32, &cls_u32);
505 }
506
u32_replace_hw_hnode(struct tcf_proto * tp,struct tc_u_hnode * h,u32 flags)507 static int u32_replace_hw_hnode(struct tcf_proto *tp, struct tc_u_hnode *h,
508 u32 flags)
509 {
510 struct net_device *dev = tp->q->dev_queue->dev;
511 struct tc_cls_u32_offload cls_u32 = {};
512 int err;
513
514 if (!tc_should_offload(dev, flags))
515 return tc_skip_sw(flags) ? -EINVAL : 0;
516
517 tc_cls_common_offload_init(&cls_u32.common, tp);
518 cls_u32.command = TC_CLSU32_NEW_HNODE;
519 cls_u32.hnode.divisor = h->divisor;
520 cls_u32.hnode.handle = h->handle;
521 cls_u32.hnode.prio = h->prio;
522
523 err = dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_CLSU32, &cls_u32);
524 if (tc_skip_sw(flags))
525 return err;
526
527 return 0;
528 }
529
u32_clear_hw_hnode(struct tcf_proto * tp,struct tc_u_hnode * h)530 static void u32_clear_hw_hnode(struct tcf_proto *tp, struct tc_u_hnode *h)
531 {
532 struct net_device *dev = tp->q->dev_queue->dev;
533 struct tc_cls_u32_offload cls_u32 = {};
534
535 if (!tc_should_offload(dev, 0))
536 return;
537
538 tc_cls_common_offload_init(&cls_u32.common, tp);
539 cls_u32.command = TC_CLSU32_DELETE_HNODE;
540 cls_u32.hnode.divisor = h->divisor;
541 cls_u32.hnode.handle = h->handle;
542 cls_u32.hnode.prio = h->prio;
543
544 dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_CLSU32, &cls_u32);
545 }
546
u32_replace_hw_knode(struct tcf_proto * tp,struct tc_u_knode * n,u32 flags)547 static int u32_replace_hw_knode(struct tcf_proto *tp, struct tc_u_knode *n,
548 u32 flags)
549 {
550 struct net_device *dev = tp->q->dev_queue->dev;
551 struct tc_cls_u32_offload cls_u32 = {};
552 int err;
553
554 if (!tc_should_offload(dev, flags))
555 return tc_skip_sw(flags) ? -EINVAL : 0;
556
557 tc_cls_common_offload_init(&cls_u32.common, tp);
558 cls_u32.command = TC_CLSU32_REPLACE_KNODE;
559 cls_u32.knode.handle = n->handle;
560 cls_u32.knode.fshift = n->fshift;
561 #ifdef CONFIG_CLS_U32_MARK
562 cls_u32.knode.val = n->val;
563 cls_u32.knode.mask = n->mask;
564 #else
565 cls_u32.knode.val = 0;
566 cls_u32.knode.mask = 0;
567 #endif
568 cls_u32.knode.sel = &n->sel;
569 cls_u32.knode.exts = &n->exts;
570 if (n->ht_down)
571 cls_u32.knode.link_handle = n->ht_down->handle;
572
573 err = dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_CLSU32, &cls_u32);
574
575 if (!err)
576 n->flags |= TCA_CLS_FLAGS_IN_HW;
577
578 if (tc_skip_sw(flags))
579 return err;
580
581 return 0;
582 }
583
u32_clear_hnode(struct tcf_proto * tp,struct tc_u_hnode * ht)584 static void u32_clear_hnode(struct tcf_proto *tp, struct tc_u_hnode *ht)
585 {
586 struct tc_u_knode *n;
587 unsigned int h;
588
589 for (h = 0; h <= ht->divisor; h++) {
590 while ((n = rtnl_dereference(ht->ht[h])) != NULL) {
591 RCU_INIT_POINTER(ht->ht[h],
592 rtnl_dereference(n->next));
593 tcf_unbind_filter(tp, &n->res);
594 u32_remove_hw_knode(tp, n->handle);
595 if (tcf_exts_get_net(&n->exts))
596 call_rcu(&n->rcu, u32_delete_key_freepf_rcu);
597 else
598 u32_destroy_key(n->tp, n, true);
599 }
600 }
601 }
602
u32_destroy_hnode(struct tcf_proto * tp,struct tc_u_hnode * ht)603 static int u32_destroy_hnode(struct tcf_proto *tp, struct tc_u_hnode *ht)
604 {
605 struct tc_u_common *tp_c = tp->data;
606 struct tc_u_hnode __rcu **hn;
607 struct tc_u_hnode *phn;
608
609 WARN_ON(ht->refcnt);
610
611 u32_clear_hnode(tp, ht);
612
613 hn = &tp_c->hlist;
614 for (phn = rtnl_dereference(*hn);
615 phn;
616 hn = &phn->next, phn = rtnl_dereference(*hn)) {
617 if (phn == ht) {
618 u32_clear_hw_hnode(tp, ht);
619 RCU_INIT_POINTER(*hn, ht->next);
620 kfree_rcu(ht, rcu);
621 return 0;
622 }
623 }
624
625 return -ENOENT;
626 }
627
ht_empty(struct tc_u_hnode * ht)628 static bool ht_empty(struct tc_u_hnode *ht)
629 {
630 unsigned int h;
631
632 for (h = 0; h <= ht->divisor; h++)
633 if (rcu_access_pointer(ht->ht[h]))
634 return false;
635
636 return true;
637 }
638
u32_destroy(struct tcf_proto * tp)639 static void u32_destroy(struct tcf_proto *tp)
640 {
641 struct tc_u_common *tp_c = tp->data;
642 struct tc_u_hnode *root_ht = rtnl_dereference(tp->root);
643
644 WARN_ON(root_ht == NULL);
645
646 if (root_ht && --root_ht->refcnt == 0)
647 u32_destroy_hnode(tp, root_ht);
648
649 if (--tp_c->refcnt == 0) {
650 struct tc_u_hnode *ht;
651
652 hlist_del(&tp_c->hnode);
653
654 while ((ht = rtnl_dereference(tp_c->hlist)) != NULL) {
655 u32_clear_hnode(tp, ht);
656 RCU_INIT_POINTER(tp_c->hlist, ht->next);
657
658 /* u32_destroy_key() will later free ht for us, if it's
659 * still referenced by some knode
660 */
661 if (--ht->refcnt == 0)
662 kfree_rcu(ht, rcu);
663 }
664
665 kfree(tp_c);
666 }
667
668 tp->data = NULL;
669 }
670
u32_delete(struct tcf_proto * tp,void * arg,bool * last)671 static int u32_delete(struct tcf_proto *tp, void *arg, bool *last)
672 {
673 struct tc_u_hnode *ht = arg;
674 struct tc_u_hnode *root_ht = rtnl_dereference(tp->root);
675 struct tc_u_common *tp_c = tp->data;
676 int ret = 0;
677
678 if (ht == NULL)
679 goto out;
680
681 if (TC_U32_KEY(ht->handle)) {
682 u32_remove_hw_knode(tp, ht->handle);
683 ret = u32_delete_key(tp, (struct tc_u_knode *)ht);
684 goto out;
685 }
686
687 if (root_ht == ht)
688 return -EINVAL;
689
690 if (ht->refcnt == 1) {
691 ht->refcnt--;
692 u32_destroy_hnode(tp, ht);
693 } else {
694 return -EBUSY;
695 }
696
697 out:
698 *last = true;
699 if (root_ht) {
700 if (root_ht->refcnt > 1) {
701 *last = false;
702 goto ret;
703 }
704 if (root_ht->refcnt == 1) {
705 if (!ht_empty(root_ht)) {
706 *last = false;
707 goto ret;
708 }
709 }
710 }
711
712 if (tp_c->refcnt > 1) {
713 *last = false;
714 goto ret;
715 }
716
717 if (tp_c->refcnt == 1) {
718 struct tc_u_hnode *ht;
719
720 for (ht = rtnl_dereference(tp_c->hlist);
721 ht;
722 ht = rtnl_dereference(ht->next))
723 if (!ht_empty(ht)) {
724 *last = false;
725 break;
726 }
727 }
728
729 ret:
730 return ret;
731 }
732
733 #define NR_U32_NODE (1<<12)
gen_new_kid(struct tc_u_hnode * ht,u32 handle)734 static u32 gen_new_kid(struct tc_u_hnode *ht, u32 handle)
735 {
736 struct tc_u_knode *n;
737 unsigned long i;
738 unsigned long *bitmap = kzalloc(BITS_TO_LONGS(NR_U32_NODE) * sizeof(unsigned long),
739 GFP_KERNEL);
740 if (!bitmap)
741 return handle | 0xFFF;
742
743 for (n = rtnl_dereference(ht->ht[TC_U32_HASH(handle)]);
744 n;
745 n = rtnl_dereference(n->next))
746 set_bit(TC_U32_NODE(n->handle), bitmap);
747
748 i = find_next_zero_bit(bitmap, NR_U32_NODE, 0x800);
749 if (i >= NR_U32_NODE)
750 i = find_next_zero_bit(bitmap, NR_U32_NODE, 1);
751
752 kfree(bitmap);
753 return handle | (i >= NR_U32_NODE ? 0xFFF : i);
754 }
755
756 static const struct nla_policy u32_policy[TCA_U32_MAX + 1] = {
757 [TCA_U32_CLASSID] = { .type = NLA_U32 },
758 [TCA_U32_HASH] = { .type = NLA_U32 },
759 [TCA_U32_LINK] = { .type = NLA_U32 },
760 [TCA_U32_DIVISOR] = { .type = NLA_U32 },
761 [TCA_U32_SEL] = { .len = sizeof(struct tc_u32_sel) },
762 [TCA_U32_INDEV] = { .type = NLA_STRING, .len = IFNAMSIZ },
763 [TCA_U32_MARK] = { .len = sizeof(struct tc_u32_mark) },
764 [TCA_U32_FLAGS] = { .type = NLA_U32 },
765 };
766
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)767 static int u32_set_parms(struct net *net, struct tcf_proto *tp,
768 unsigned long base, struct tc_u_hnode *ht,
769 struct tc_u_knode *n, struct nlattr **tb,
770 struct nlattr *est, bool ovr)
771 {
772 int err;
773
774 err = tcf_exts_validate(net, tp, tb, est, &n->exts, ovr);
775 if (err < 0)
776 return err;
777
778 if (tb[TCA_U32_LINK]) {
779 u32 handle = nla_get_u32(tb[TCA_U32_LINK]);
780 struct tc_u_hnode *ht_down = NULL, *ht_old;
781
782 if (TC_U32_KEY(handle))
783 return -EINVAL;
784
785 if (handle) {
786 ht_down = u32_lookup_ht(ht->tp_c, handle);
787
788 if (ht_down == NULL)
789 return -EINVAL;
790 ht_down->refcnt++;
791 }
792
793 ht_old = rtnl_dereference(n->ht_down);
794 rcu_assign_pointer(n->ht_down, ht_down);
795
796 if (ht_old)
797 ht_old->refcnt--;
798 }
799 if (tb[TCA_U32_CLASSID]) {
800 n->res.classid = nla_get_u32(tb[TCA_U32_CLASSID]);
801 tcf_bind_filter(tp, &n->res, base);
802 }
803
804 #ifdef CONFIG_NET_CLS_IND
805 if (tb[TCA_U32_INDEV]) {
806 int ret;
807 ret = tcf_change_indev(net, tb[TCA_U32_INDEV]);
808 if (ret < 0)
809 return -EINVAL;
810 n->ifindex = ret;
811 }
812 #endif
813 return 0;
814 }
815
u32_replace_knode(struct tcf_proto * tp,struct tc_u_common * tp_c,struct tc_u_knode * n)816 static void u32_replace_knode(struct tcf_proto *tp, struct tc_u_common *tp_c,
817 struct tc_u_knode *n)
818 {
819 struct tc_u_knode __rcu **ins;
820 struct tc_u_knode *pins;
821 struct tc_u_hnode *ht;
822
823 if (TC_U32_HTID(n->handle) == TC_U32_ROOT)
824 ht = rtnl_dereference(tp->root);
825 else
826 ht = u32_lookup_ht(tp_c, TC_U32_HTID(n->handle));
827
828 ins = &ht->ht[TC_U32_HASH(n->handle)];
829
830 /* The node must always exist for it to be replaced if this is not the
831 * case then something went very wrong elsewhere.
832 */
833 for (pins = rtnl_dereference(*ins); ;
834 ins = &pins->next, pins = rtnl_dereference(*ins))
835 if (pins->handle == n->handle)
836 break;
837
838 RCU_INIT_POINTER(n->next, pins->next);
839 rcu_assign_pointer(*ins, n);
840 }
841
u32_init_knode(struct tcf_proto * tp,struct tc_u_knode * n)842 static struct tc_u_knode *u32_init_knode(struct tcf_proto *tp,
843 struct tc_u_knode *n)
844 {
845 struct tc_u_knode *new;
846 struct tc_u32_sel *s = &n->sel;
847
848 new = kzalloc(sizeof(*n) + s->nkeys*sizeof(struct tc_u32_key),
849 GFP_KERNEL);
850
851 if (!new)
852 return NULL;
853
854 RCU_INIT_POINTER(new->next, n->next);
855 new->handle = n->handle;
856 RCU_INIT_POINTER(new->ht_up, n->ht_up);
857
858 #ifdef CONFIG_NET_CLS_IND
859 new->ifindex = n->ifindex;
860 #endif
861 new->fshift = n->fshift;
862 new->res = n->res;
863 new->flags = n->flags;
864 RCU_INIT_POINTER(new->ht_down, n->ht_down);
865
866 /* bump reference count as long as we hold pointer to structure */
867 if (new->ht_down)
868 new->ht_down->refcnt++;
869
870 #ifdef CONFIG_CLS_U32_PERF
871 /* Statistics may be incremented by readers during update
872 * so we must keep them in tact. When the node is later destroyed
873 * a special destroy call must be made to not free the pf memory.
874 */
875 new->pf = n->pf;
876 #endif
877
878 #ifdef CONFIG_CLS_U32_MARK
879 new->val = n->val;
880 new->mask = n->mask;
881 /* Similarly success statistics must be moved as pointers */
882 new->pcpu_success = n->pcpu_success;
883 #endif
884 new->tp = tp;
885 memcpy(&new->sel, s, sizeof(*s) + s->nkeys*sizeof(struct tc_u32_key));
886
887 if (tcf_exts_init(&new->exts, TCA_U32_ACT, TCA_U32_POLICE)) {
888 kfree(new);
889 return NULL;
890 }
891
892 return new;
893 }
894
u32_change(struct net * net,struct sk_buff * in_skb,struct tcf_proto * tp,unsigned long base,u32 handle,struct nlattr ** tca,void ** arg,bool ovr)895 static int u32_change(struct net *net, struct sk_buff *in_skb,
896 struct tcf_proto *tp, unsigned long base, u32 handle,
897 struct nlattr **tca, void **arg, bool ovr)
898 {
899 struct tc_u_common *tp_c = tp->data;
900 struct tc_u_hnode *ht;
901 struct tc_u_knode *n;
902 struct tc_u32_sel *s;
903 struct nlattr *opt = tca[TCA_OPTIONS];
904 struct nlattr *tb[TCA_U32_MAX + 1];
905 u32 htid, flags = 0;
906 size_t sel_size;
907 int err;
908 #ifdef CONFIG_CLS_U32_PERF
909 size_t size;
910 #endif
911
912 if (opt == NULL)
913 return handle ? -EINVAL : 0;
914
915 err = nla_parse_nested(tb, TCA_U32_MAX, opt, u32_policy, NULL);
916 if (err < 0)
917 return err;
918
919 if (tb[TCA_U32_FLAGS]) {
920 flags = nla_get_u32(tb[TCA_U32_FLAGS]);
921 if (!tc_flags_valid(flags))
922 return -EINVAL;
923 }
924
925 n = *arg;
926 if (n) {
927 struct tc_u_knode *new;
928
929 if (TC_U32_KEY(n->handle) == 0)
930 return -EINVAL;
931
932 if ((n->flags ^ flags) &
933 ~(TCA_CLS_FLAGS_IN_HW | TCA_CLS_FLAGS_NOT_IN_HW))
934 return -EINVAL;
935
936 new = u32_init_knode(tp, n);
937 if (!new)
938 return -ENOMEM;
939
940 err = u32_set_parms(net, tp, base,
941 rtnl_dereference(n->ht_up), new, tb,
942 tca[TCA_RATE], ovr);
943
944 if (err) {
945 u32_destroy_key(tp, new, false);
946 return err;
947 }
948
949 err = u32_replace_hw_knode(tp, new, flags);
950 if (err) {
951 u32_destroy_key(tp, new, false);
952 return err;
953 }
954
955 if (!tc_in_hw(new->flags))
956 new->flags |= TCA_CLS_FLAGS_NOT_IN_HW;
957
958 u32_replace_knode(tp, tp_c, new);
959 tcf_unbind_filter(tp, &n->res);
960 tcf_exts_get_net(&n->exts);
961 call_rcu(&n->rcu, u32_delete_key_rcu);
962 return 0;
963 }
964
965 if (tb[TCA_U32_DIVISOR]) {
966 unsigned int divisor = nla_get_u32(tb[TCA_U32_DIVISOR]);
967
968 if (--divisor > 0x100)
969 return -EINVAL;
970 if (TC_U32_KEY(handle))
971 return -EINVAL;
972 if (handle == 0) {
973 handle = gen_new_htid(tp->data);
974 if (handle == 0)
975 return -ENOMEM;
976 }
977 ht = kzalloc(sizeof(*ht) + divisor*sizeof(void *), GFP_KERNEL);
978 if (ht == NULL)
979 return -ENOBUFS;
980 ht->tp_c = tp_c;
981 ht->refcnt = 1;
982 ht->divisor = divisor;
983 ht->handle = handle;
984 ht->prio = tp->prio;
985
986 err = u32_replace_hw_hnode(tp, ht, flags);
987 if (err) {
988 kfree(ht);
989 return err;
990 }
991
992 RCU_INIT_POINTER(ht->next, tp_c->hlist);
993 rcu_assign_pointer(tp_c->hlist, ht);
994 *arg = ht;
995
996 return 0;
997 }
998
999 if (tb[TCA_U32_HASH]) {
1000 htid = nla_get_u32(tb[TCA_U32_HASH]);
1001 if (TC_U32_HTID(htid) == TC_U32_ROOT) {
1002 ht = rtnl_dereference(tp->root);
1003 htid = ht->handle;
1004 } else {
1005 ht = u32_lookup_ht(tp->data, TC_U32_HTID(htid));
1006 if (ht == NULL)
1007 return -EINVAL;
1008 }
1009 } else {
1010 ht = rtnl_dereference(tp->root);
1011 htid = ht->handle;
1012 }
1013
1014 if (ht->divisor < TC_U32_HASH(htid))
1015 return -EINVAL;
1016
1017 if (handle) {
1018 if (TC_U32_HTID(handle) && TC_U32_HTID(handle^htid))
1019 return -EINVAL;
1020 handle = htid | TC_U32_NODE(handle);
1021 } else
1022 handle = gen_new_kid(ht, htid);
1023
1024 if (tb[TCA_U32_SEL] == NULL)
1025 return -EINVAL;
1026
1027 s = nla_data(tb[TCA_U32_SEL]);
1028 sel_size = sizeof(*s) + sizeof(*s->keys) * s->nkeys;
1029 if (nla_len(tb[TCA_U32_SEL]) < sel_size)
1030 return -EINVAL;
1031
1032 n = kzalloc(offsetof(typeof(*n), sel) + sel_size, GFP_KERNEL);
1033 if (n == NULL)
1034 return -ENOBUFS;
1035
1036 #ifdef CONFIG_CLS_U32_PERF
1037 size = sizeof(struct tc_u32_pcnt) + s->nkeys * sizeof(u64);
1038 n->pf = __alloc_percpu(size, __alignof__(struct tc_u32_pcnt));
1039 if (!n->pf) {
1040 kfree(n);
1041 return -ENOBUFS;
1042 }
1043 #endif
1044
1045 memcpy(&n->sel, s, sel_size);
1046 RCU_INIT_POINTER(n->ht_up, ht);
1047 n->handle = handle;
1048 n->fshift = s->hmask ? ffs(ntohl(s->hmask)) - 1 : 0;
1049 n->flags = flags;
1050 n->tp = tp;
1051
1052 err = tcf_exts_init(&n->exts, TCA_U32_ACT, TCA_U32_POLICE);
1053 if (err < 0)
1054 goto errout;
1055
1056 #ifdef CONFIG_CLS_U32_MARK
1057 n->pcpu_success = alloc_percpu(u32);
1058 if (!n->pcpu_success) {
1059 err = -ENOMEM;
1060 goto errout;
1061 }
1062
1063 if (tb[TCA_U32_MARK]) {
1064 struct tc_u32_mark *mark;
1065
1066 mark = nla_data(tb[TCA_U32_MARK]);
1067 n->val = mark->val;
1068 n->mask = mark->mask;
1069 }
1070 #endif
1071
1072 err = u32_set_parms(net, tp, base, ht, n, tb, tca[TCA_RATE], ovr);
1073 if (err == 0) {
1074 struct tc_u_knode __rcu **ins;
1075 struct tc_u_knode *pins;
1076
1077 err = u32_replace_hw_knode(tp, n, flags);
1078 if (err)
1079 goto errhw;
1080
1081 if (!tc_in_hw(n->flags))
1082 n->flags |= TCA_CLS_FLAGS_NOT_IN_HW;
1083
1084 ins = &ht->ht[TC_U32_HASH(handle)];
1085 for (pins = rtnl_dereference(*ins); pins;
1086 ins = &pins->next, pins = rtnl_dereference(*ins))
1087 if (TC_U32_NODE(handle) < TC_U32_NODE(pins->handle))
1088 break;
1089
1090 RCU_INIT_POINTER(n->next, pins);
1091 rcu_assign_pointer(*ins, n);
1092 *arg = n;
1093 return 0;
1094 }
1095
1096 errhw:
1097 #ifdef CONFIG_CLS_U32_MARK
1098 free_percpu(n->pcpu_success);
1099 #endif
1100
1101 errout:
1102 tcf_exts_destroy(&n->exts);
1103 #ifdef CONFIG_CLS_U32_PERF
1104 free_percpu(n->pf);
1105 #endif
1106 kfree(n);
1107 return err;
1108 }
1109
u32_walk(struct tcf_proto * tp,struct tcf_walker * arg)1110 static void u32_walk(struct tcf_proto *tp, struct tcf_walker *arg)
1111 {
1112 struct tc_u_common *tp_c = tp->data;
1113 struct tc_u_hnode *ht;
1114 struct tc_u_knode *n;
1115 unsigned int h;
1116
1117 if (arg->stop)
1118 return;
1119
1120 for (ht = rtnl_dereference(tp_c->hlist);
1121 ht;
1122 ht = rtnl_dereference(ht->next)) {
1123 if (ht->prio != tp->prio)
1124 continue;
1125 if (arg->count >= arg->skip) {
1126 if (arg->fn(tp, ht, arg) < 0) {
1127 arg->stop = 1;
1128 return;
1129 }
1130 }
1131 arg->count++;
1132 for (h = 0; h <= ht->divisor; h++) {
1133 for (n = rtnl_dereference(ht->ht[h]);
1134 n;
1135 n = rtnl_dereference(n->next)) {
1136 if (arg->count < arg->skip) {
1137 arg->count++;
1138 continue;
1139 }
1140 if (arg->fn(tp, n, arg) < 0) {
1141 arg->stop = 1;
1142 return;
1143 }
1144 arg->count++;
1145 }
1146 }
1147 }
1148 }
1149
u32_bind_class(void * fh,u32 classid,unsigned long cl)1150 static void u32_bind_class(void *fh, u32 classid, unsigned long cl)
1151 {
1152 struct tc_u_knode *n = fh;
1153
1154 if (n && n->res.classid == classid)
1155 n->res.class = cl;
1156 }
1157
u32_dump(struct net * net,struct tcf_proto * tp,void * fh,struct sk_buff * skb,struct tcmsg * t)1158 static int u32_dump(struct net *net, struct tcf_proto *tp, void *fh,
1159 struct sk_buff *skb, struct tcmsg *t)
1160 {
1161 struct tc_u_knode *n = fh;
1162 struct tc_u_hnode *ht_up, *ht_down;
1163 struct nlattr *nest;
1164
1165 if (n == NULL)
1166 return skb->len;
1167
1168 t->tcm_handle = n->handle;
1169
1170 nest = nla_nest_start(skb, TCA_OPTIONS);
1171 if (nest == NULL)
1172 goto nla_put_failure;
1173
1174 if (TC_U32_KEY(n->handle) == 0) {
1175 struct tc_u_hnode *ht = fh;
1176 u32 divisor = ht->divisor + 1;
1177
1178 if (nla_put_u32(skb, TCA_U32_DIVISOR, divisor))
1179 goto nla_put_failure;
1180 } else {
1181 #ifdef CONFIG_CLS_U32_PERF
1182 struct tc_u32_pcnt *gpf;
1183 int cpu;
1184 #endif
1185
1186 if (nla_put(skb, TCA_U32_SEL,
1187 sizeof(n->sel) + n->sel.nkeys*sizeof(struct tc_u32_key),
1188 &n->sel))
1189 goto nla_put_failure;
1190
1191 ht_up = rtnl_dereference(n->ht_up);
1192 if (ht_up) {
1193 u32 htid = n->handle & 0xFFFFF000;
1194 if (nla_put_u32(skb, TCA_U32_HASH, htid))
1195 goto nla_put_failure;
1196 }
1197 if (n->res.classid &&
1198 nla_put_u32(skb, TCA_U32_CLASSID, n->res.classid))
1199 goto nla_put_failure;
1200
1201 ht_down = rtnl_dereference(n->ht_down);
1202 if (ht_down &&
1203 nla_put_u32(skb, TCA_U32_LINK, ht_down->handle))
1204 goto nla_put_failure;
1205
1206 if (n->flags && nla_put_u32(skb, TCA_U32_FLAGS, n->flags))
1207 goto nla_put_failure;
1208
1209 #ifdef CONFIG_CLS_U32_MARK
1210 if ((n->val || n->mask)) {
1211 struct tc_u32_mark mark = {.val = n->val,
1212 .mask = n->mask,
1213 .success = 0};
1214 int cpum;
1215
1216 for_each_possible_cpu(cpum) {
1217 __u32 cnt = *per_cpu_ptr(n->pcpu_success, cpum);
1218
1219 mark.success += cnt;
1220 }
1221
1222 if (nla_put(skb, TCA_U32_MARK, sizeof(mark), &mark))
1223 goto nla_put_failure;
1224 }
1225 #endif
1226
1227 if (tcf_exts_dump(skb, &n->exts) < 0)
1228 goto nla_put_failure;
1229
1230 #ifdef CONFIG_NET_CLS_IND
1231 if (n->ifindex) {
1232 struct net_device *dev;
1233 dev = __dev_get_by_index(net, n->ifindex);
1234 if (dev && nla_put_string(skb, TCA_U32_INDEV, dev->name))
1235 goto nla_put_failure;
1236 }
1237 #endif
1238 #ifdef CONFIG_CLS_U32_PERF
1239 gpf = kzalloc(sizeof(struct tc_u32_pcnt) +
1240 n->sel.nkeys * sizeof(u64),
1241 GFP_KERNEL);
1242 if (!gpf)
1243 goto nla_put_failure;
1244
1245 for_each_possible_cpu(cpu) {
1246 int i;
1247 struct tc_u32_pcnt *pf = per_cpu_ptr(n->pf, cpu);
1248
1249 gpf->rcnt += pf->rcnt;
1250 gpf->rhit += pf->rhit;
1251 for (i = 0; i < n->sel.nkeys; i++)
1252 gpf->kcnts[i] += pf->kcnts[i];
1253 }
1254
1255 if (nla_put_64bit(skb, TCA_U32_PCNT,
1256 sizeof(struct tc_u32_pcnt) +
1257 n->sel.nkeys * sizeof(u64),
1258 gpf, TCA_U32_PAD)) {
1259 kfree(gpf);
1260 goto nla_put_failure;
1261 }
1262 kfree(gpf);
1263 #endif
1264 }
1265
1266 nla_nest_end(skb, nest);
1267
1268 if (TC_U32_KEY(n->handle))
1269 if (tcf_exts_dump_stats(skb, &n->exts) < 0)
1270 goto nla_put_failure;
1271 return skb->len;
1272
1273 nla_put_failure:
1274 nla_nest_cancel(skb, nest);
1275 return -1;
1276 }
1277
1278 static struct tcf_proto_ops cls_u32_ops __read_mostly = {
1279 .kind = "u32",
1280 .classify = u32_classify,
1281 .init = u32_init,
1282 .destroy = u32_destroy,
1283 .get = u32_get,
1284 .change = u32_change,
1285 .delete = u32_delete,
1286 .walk = u32_walk,
1287 .dump = u32_dump,
1288 .bind_class = u32_bind_class,
1289 .owner = THIS_MODULE,
1290 };
1291
init_u32(void)1292 static int __init init_u32(void)
1293 {
1294 int i, ret;
1295
1296 pr_info("u32 classifier\n");
1297 #ifdef CONFIG_CLS_U32_PERF
1298 pr_info(" Performance counters on\n");
1299 #endif
1300 #ifdef CONFIG_NET_CLS_IND
1301 pr_info(" input device check on\n");
1302 #endif
1303 #ifdef CONFIG_NET_CLS_ACT
1304 pr_info(" Actions configured\n");
1305 #endif
1306 tc_u_common_hash = kvmalloc_array(U32_HASH_SIZE,
1307 sizeof(struct hlist_head),
1308 GFP_KERNEL);
1309 if (!tc_u_common_hash)
1310 return -ENOMEM;
1311
1312 for (i = 0; i < U32_HASH_SIZE; i++)
1313 INIT_HLIST_HEAD(&tc_u_common_hash[i]);
1314
1315 ret = register_tcf_proto_ops(&cls_u32_ops);
1316 if (ret)
1317 kvfree(tc_u_common_hash);
1318 return ret;
1319 }
1320
exit_u32(void)1321 static void __exit exit_u32(void)
1322 {
1323 unregister_tcf_proto_ops(&cls_u32_ops);
1324 kvfree(tc_u_common_hash);
1325 }
1326
1327 module_init(init_u32)
1328 module_exit(exit_u32)
1329 MODULE_LICENSE("GPL");
1330