xref: /linux/net/sched/cls_u32.c (revision 8fdb05de0e2db89d8f56144c60ab784812e8c3b7)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * net/sched/cls_u32.c	Ugly (or Universal) 32bit key Packet Classifier.
4  *
5  * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
6  *
7  *	The filters are packed to hash tables of key nodes
8  *	with a set of 32bit key/mask pairs at every node.
9  *	Nodes reference next level hash tables etc.
10  *
11  *	This scheme is the best universal classifier I managed to
12  *	invent; it is not super-fast, but it is not slow (provided you
13  *	program it correctly), and general enough.  And its relative
14  *	speed grows as the number of rules becomes larger.
15  *
16  *	It seems that it represents the best middle point between
17  *	speed and manageability both by human and by machine.
18  *
19  *	It is especially useful for link sharing combined with QoS;
20  *	pure RSVP doesn't need such a general approach and can use
21  *	much simpler (and faster) schemes, sort of cls_rsvp.c.
22  *
23  *	nfmark match added by Catalin(ux aka Dino) BOIE <catab at umbrella.ro>
24  */
25 
26 #include <linux/module.h>
27 #include <linux/slab.h>
28 #include <linux/types.h>
29 #include <linux/kernel.h>
30 #include <linux/string.h>
31 #include <linux/errno.h>
32 #include <linux/percpu.h>
33 #include <linux/rtnetlink.h>
34 #include <linux/skbuff.h>
35 #include <linux/bitmap.h>
36 #include <linux/netdevice.h>
37 #include <linux/hash.h>
38 #include <net/netlink.h>
39 #include <net/act_api.h>
40 #include <net/pkt_cls.h>
41 #include <linux/idr.h>
42 #include <net/tc_wrapper.h>
43 
44 struct tc_u_knode {
45 	struct tc_u_knode __rcu	*next;
46 	u32			handle;
47 	struct tc_u_hnode __rcu	*ht_up;
48 	struct tcf_exts		exts;
49 	int			ifindex;
50 	u8			fshift;
51 	struct tcf_result	res;
52 	struct tc_u_hnode __rcu	*ht_down;
53 #ifdef CONFIG_CLS_U32_PERF
54 	struct tc_u32_pcnt __percpu *pf;
55 #endif
56 	u32			flags;
57 	unsigned int		in_hw_count;
58 #ifdef CONFIG_CLS_U32_MARK
59 	u32			val;
60 	u32			mask;
61 	u32 __percpu		*pcpu_success;
62 #endif
63 	struct rcu_work		rwork;
64 	/* The 'sel' field MUST be the last field in structure to allow for
65 	 * tc_u32_keys allocated at end of structure.
66 	 */
67 	struct tc_u32_sel	sel;
68 };
69 
70 struct tc_u_hnode {
71 	struct tc_u_hnode __rcu	*next;
72 	u32			handle;
73 	u32			prio;
74 	refcount_t		refcnt;
75 	unsigned int		divisor;
76 	struct idr		handle_idr;
77 	bool			is_root;
78 	struct rcu_head		rcu;
79 	u32			flags;
80 	/* The 'ht' field MUST be the last field in structure to allow for
81 	 * more entries allocated at end of structure.
82 	 */
83 	struct tc_u_knode __rcu	*ht[];
84 };
85 
86 struct tc_u_common {
87 	struct tc_u_hnode __rcu	*hlist;
88 	void			*ptr;
89 	refcount_t		refcnt;
90 	struct idr		handle_idr;
91 	struct hlist_node	hnode;
92 	long			knodes;
93 };
94 
handle2id(u32 h)95 static u32 handle2id(u32 h)
96 {
97 	return ((h & 0x80000000) ? ((h >> 20) & 0x7FF) : h);
98 }
99 
id2handle(u32 id)100 static u32 id2handle(u32 id)
101 {
102 	return (id | 0x800U) << 20;
103 }
104 
u32_hash_fold(__be32 key,const struct tc_u32_sel * sel,u8 fshift)105 static inline unsigned int u32_hash_fold(__be32 key,
106 					 const struct tc_u32_sel *sel,
107 					 u8 fshift)
108 {
109 	unsigned int h = ntohl(key & sel->hmask) >> fshift;
110 
111 	return h;
112 }
113 
u32_classify(struct sk_buff * skb,const struct tcf_proto * tp,struct tcf_result * res)114 TC_INDIRECT_SCOPE int u32_classify(struct sk_buff *skb,
115 				   const struct tcf_proto *tp,
116 				   struct tcf_result *res)
117 {
118 	struct {
119 		struct tc_u_knode *knode;
120 		unsigned int	  off;
121 	} stack[TC_U32_MAXDEPTH];
122 
123 	struct tc_u_hnode *ht = rcu_dereference_bh(tp->root);
124 	unsigned int off = skb_network_offset(skb);
125 	struct tc_u_knode *n;
126 	int sdepth = 0;
127 	int off2 = 0;
128 	int sel = 0;
129 #ifdef CONFIG_CLS_U32_PERF
130 	int j;
131 #endif
132 	int i, r;
133 
134 next_ht:
135 	n = rcu_dereference_bh(ht->ht[sel]);
136 
137 next_knode:
138 	if (n) {
139 		struct tc_u32_key *key = n->sel.keys;
140 
141 #ifdef CONFIG_CLS_U32_PERF
142 		__this_cpu_inc(n->pf->rcnt);
143 		j = 0;
144 #endif
145 
146 		if (tc_skip_sw(n->flags)) {
147 			n = rcu_dereference_bh(n->next);
148 			goto next_knode;
149 		}
150 
151 #ifdef CONFIG_CLS_U32_MARK
152 		if ((skb->mark & n->mask) != n->val) {
153 			n = rcu_dereference_bh(n->next);
154 			goto next_knode;
155 		} else {
156 			__this_cpu_inc(*n->pcpu_success);
157 		}
158 #endif
159 
160 		for (i = n->sel.nkeys; i > 0; i--, key++) {
161 			int toff = off + key->off + (off2 & key->offmask);
162 			__be32 *data, hdata;
163 
164 			data = skb_header_pointer_careful(skb, toff, 4,
165 							  &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 				if (!tcf_match_indev(skb, n->ifindex)) {
185 					n = rcu_dereference_bh(n->next);
186 					goto next_knode;
187 				}
188 #ifdef CONFIG_CLS_U32_PERF
189 				__this_cpu_inc(n->pf->rhit);
190 #endif
191 				r = tcf_exts_exec(skb, &n->exts, res);
192 				if (r < 0) {
193 					n = rcu_dereference_bh(n->next);
194 					goto next_knode;
195 				}
196 
197 				return r;
198 			}
199 			n = rcu_dereference_bh(n->next);
200 			goto next_knode;
201 		}
202 
203 		/* PUSH */
204 		if (sdepth >= TC_U32_MAXDEPTH)
205 			goto deadloop;
206 		stack[sdepth].knode = n;
207 		stack[sdepth].off = off;
208 		sdepth++;
209 
210 		ht = rcu_dereference_bh(n->ht_down);
211 		sel = 0;
212 		if (ht->divisor) {
213 			__be32 *data, hdata;
214 
215 			data = skb_header_pointer_careful(skb,
216 							  off + n->sel.hoff,
217 							  4, &hdata);
218 			if (!data)
219 				goto out;
220 			sel = ht->divisor & u32_hash_fold(*data, &n->sel,
221 							  n->fshift);
222 		}
223 		if (!(n->sel.flags & (TC_U32_VAROFFSET | TC_U32_OFFSET | TC_U32_EAT)))
224 			goto next_ht;
225 
226 		if (n->sel.flags & (TC_U32_OFFSET | TC_U32_VAROFFSET)) {
227 			off2 = n->sel.off + 3;
228 			if (n->sel.flags & TC_U32_VAROFFSET) {
229 				__be16 *data, hdata;
230 
231 				data = skb_header_pointer_careful(skb,
232 							  off + n->sel.offoff,
233 							  2, &hdata);
234 				if (!data)
235 					goto out;
236 				off2 += ntohs(n->sel.offmask & *data) >>
237 					n->sel.offshift;
238 			}
239 			off2 &= ~3;
240 		}
241 		if (n->sel.flags & TC_U32_EAT) {
242 			off += off2;
243 			off2 = 0;
244 		}
245 
246 		if (off < skb->len)
247 			goto next_ht;
248 	}
249 
250 	/* POP */
251 	if (sdepth--) {
252 		n = stack[sdepth].knode;
253 		ht = rcu_dereference_bh(n->ht_up);
254 		off = stack[sdepth].off;
255 		goto check_terminal;
256 	}
257 out:
258 	return -1;
259 
260 deadloop:
261 	net_warn_ratelimited("cls_u32: dead loop\n");
262 	return -1;
263 }
264 
u32_lookup_ht(struct tc_u_common * tp_c,u32 handle)265 static struct tc_u_hnode *u32_lookup_ht(struct tc_u_common *tp_c, u32 handle)
266 {
267 	struct tc_u_hnode *ht;
268 
269 	for (ht = rtnl_dereference(tp_c->hlist);
270 	     ht;
271 	     ht = rtnl_dereference(ht->next))
272 		if (ht->handle == handle)
273 			break;
274 
275 	return ht;
276 }
277 
u32_lookup_key(struct tc_u_hnode * ht,u32 handle)278 static struct tc_u_knode *u32_lookup_key(struct tc_u_hnode *ht, u32 handle)
279 {
280 	unsigned int sel;
281 	struct tc_u_knode *n = NULL;
282 
283 	sel = TC_U32_HASH(handle);
284 	if (sel > ht->divisor)
285 		goto out;
286 
287 	for (n = rtnl_dereference(ht->ht[sel]);
288 	     n;
289 	     n = rtnl_dereference(n->next))
290 		if (n->handle == handle)
291 			break;
292 out:
293 	return n;
294 }
295 
296 
u32_get(struct tcf_proto * tp,u32 handle)297 static void *u32_get(struct tcf_proto *tp, u32 handle)
298 {
299 	struct tc_u_hnode *ht;
300 	struct tc_u_common *tp_c = tp->data;
301 
302 	if (TC_U32_HTID(handle) == TC_U32_ROOT)
303 		ht = rtnl_dereference(tp->root);
304 	else
305 		ht = u32_lookup_ht(tp_c, TC_U32_HTID(handle));
306 
307 	if (!ht)
308 		return NULL;
309 
310 	if (TC_U32_KEY(handle) == 0)
311 		return ht;
312 
313 	return u32_lookup_key(ht, handle);
314 }
315 
316 /* Protected by rtnl lock */
gen_new_htid(struct tc_u_common * tp_c,struct tc_u_hnode * ptr)317 static u32 gen_new_htid(struct tc_u_common *tp_c, struct tc_u_hnode *ptr)
318 {
319 	int id = idr_alloc_cyclic(&tp_c->handle_idr, ptr, 1, 0x7FF, GFP_KERNEL);
320 	if (id < 0)
321 		return 0;
322 	return id2handle(id);
323 }
324 
325 static struct hlist_head *tc_u_common_hash;
326 
327 #define U32_HASH_SHIFT 10
328 #define U32_HASH_SIZE (1 << U32_HASH_SHIFT)
329 
tc_u_common_ptr(const struct tcf_proto * tp)330 static void *tc_u_common_ptr(const struct tcf_proto *tp)
331 {
332 	struct tcf_block *block = tp->chain->block;
333 
334 	/* The block sharing is currently supported only
335 	 * for classless qdiscs. In that case we use block
336 	 * for tc_u_common identification. In case the
337 	 * block is not shared, block->q is a valid pointer
338 	 * and we can use that. That works for classful qdiscs.
339 	 */
340 	if (tcf_block_shared(block))
341 		return block;
342 	else
343 		return block->q;
344 }
345 
tc_u_hash(void * key)346 static struct hlist_head *tc_u_hash(void *key)
347 {
348 	return tc_u_common_hash + hash_ptr(key, U32_HASH_SHIFT);
349 }
350 
tc_u_common_find(void * key)351 static struct tc_u_common *tc_u_common_find(void *key)
352 {
353 	struct tc_u_common *tc;
354 	hlist_for_each_entry(tc, tc_u_hash(key), hnode) {
355 		if (tc->ptr == key)
356 			return tc;
357 	}
358 	return NULL;
359 }
360 
u32_init(struct tcf_proto * tp)361 static int u32_init(struct tcf_proto *tp)
362 {
363 	struct tc_u_hnode *root_ht;
364 	void *key = tc_u_common_ptr(tp);
365 	struct tc_u_common *tp_c = tc_u_common_find(key);
366 
367 	root_ht = kzalloc(struct_size(root_ht, ht, 1), GFP_KERNEL);
368 	if (root_ht == NULL)
369 		return -ENOBUFS;
370 
371 	refcount_set(&root_ht->refcnt, 1);
372 	root_ht->handle = tp_c ? gen_new_htid(tp_c, root_ht) : id2handle(0);
373 	root_ht->prio = tp->prio;
374 	root_ht->is_root = true;
375 	idr_init(&root_ht->handle_idr);
376 
377 	if (tp_c == NULL) {
378 		tp_c = kzalloc(sizeof(*tp_c), GFP_KERNEL);
379 		if (tp_c == NULL) {
380 			kfree(root_ht);
381 			return -ENOBUFS;
382 		}
383 		refcount_set(&tp_c->refcnt, 1);
384 		tp_c->ptr = key;
385 		INIT_HLIST_NODE(&tp_c->hnode);
386 		idr_init(&tp_c->handle_idr);
387 
388 		hlist_add_head(&tp_c->hnode, tc_u_hash(key));
389 	} else {
390 		refcount_inc(&tp_c->refcnt);
391 	}
392 
393 	RCU_INIT_POINTER(root_ht->next, tp_c->hlist);
394 	rcu_assign_pointer(tp_c->hlist, root_ht);
395 
396 	/* root_ht must be destroyed when tcf_proto is destroyed */
397 	rcu_assign_pointer(tp->root, root_ht);
398 	tp->data = tp_c;
399 	return 0;
400 }
401 
__u32_destroy_key(struct tc_u_knode * n)402 static void __u32_destroy_key(struct tc_u_knode *n)
403 {
404 	struct tc_u_hnode *ht = rtnl_dereference(n->ht_down);
405 
406 	tcf_exts_destroy(&n->exts);
407 	if (ht && refcount_dec_and_test(&ht->refcnt))
408 		kfree(ht);
409 	kfree(n);
410 }
411 
u32_destroy_key(struct tc_u_knode * n,bool free_pf)412 static void u32_destroy_key(struct tc_u_knode *n, bool free_pf)
413 {
414 	tcf_exts_put_net(&n->exts);
415 #ifdef CONFIG_CLS_U32_PERF
416 	if (free_pf)
417 		free_percpu(n->pf);
418 #endif
419 #ifdef CONFIG_CLS_U32_MARK
420 	if (free_pf)
421 		free_percpu(n->pcpu_success);
422 #endif
423 	__u32_destroy_key(n);
424 }
425 
426 /* u32_delete_key_rcu should be called when free'ing a copied
427  * version of a tc_u_knode obtained from u32_init_knode(). When
428  * copies are obtained from u32_init_knode() the statistics are
429  * shared between the old and new copies to allow readers to
430  * continue to update the statistics during the copy. To support
431  * this the u32_delete_key_rcu variant does not free the percpu
432  * statistics.
433  */
u32_delete_key_work(struct work_struct * work)434 static void u32_delete_key_work(struct work_struct *work)
435 {
436 	struct tc_u_knode *key = container_of(to_rcu_work(work),
437 					      struct tc_u_knode,
438 					      rwork);
439 	rtnl_lock();
440 	u32_destroy_key(key, false);
441 	rtnl_unlock();
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(to_rcu_work(work),
454 					      struct tc_u_knode,
455 					      rwork);
456 	rtnl_lock();
457 	u32_destroy_key(key, true);
458 	rtnl_unlock();
459 }
460 
u32_delete_key(struct tcf_proto * tp,struct tc_u_knode * key)461 static int u32_delete_key(struct tcf_proto *tp, struct tc_u_knode *key)
462 {
463 	struct tc_u_common *tp_c = tp->data;
464 	struct tc_u_knode __rcu **kp;
465 	struct tc_u_knode *pkp;
466 	struct tc_u_hnode *ht = rtnl_dereference(key->ht_up);
467 
468 	if (ht) {
469 		kp = &ht->ht[TC_U32_HASH(key->handle)];
470 		for (pkp = rtnl_dereference(*kp); pkp;
471 		     kp = &pkp->next, pkp = rtnl_dereference(*kp)) {
472 			if (pkp == key) {
473 				RCU_INIT_POINTER(*kp, key->next);
474 				tp_c->knodes--;
475 
476 				tcf_unbind_filter(tp, &key->res);
477 				idr_remove(&ht->handle_idr, key->handle);
478 				tcf_exts_get_net(&key->exts);
479 				tcf_queue_work(&key->rwork, u32_delete_key_freepf_work);
480 				return 0;
481 			}
482 		}
483 	}
484 	WARN_ON(1);
485 	return 0;
486 }
487 
u32_clear_hw_hnode(struct tcf_proto * tp,struct tc_u_hnode * h,struct netlink_ext_ack * extack)488 static void u32_clear_hw_hnode(struct tcf_proto *tp, struct tc_u_hnode *h,
489 			       struct netlink_ext_ack *extack)
490 {
491 	struct tcf_block *block = tp->chain->block;
492 	struct tc_cls_u32_offload cls_u32 = {};
493 
494 	tc_cls_common_offload_init(&cls_u32.common, tp, h->flags, extack);
495 	cls_u32.command = TC_CLSU32_DELETE_HNODE;
496 	cls_u32.hnode.divisor = h->divisor;
497 	cls_u32.hnode.handle = h->handle;
498 	cls_u32.hnode.prio = h->prio;
499 
500 	tc_setup_cb_call(block, TC_SETUP_CLSU32, &cls_u32, false, true);
501 }
502 
u32_replace_hw_hnode(struct tcf_proto * tp,struct tc_u_hnode * h,u32 flags,struct netlink_ext_ack * extack)503 static int u32_replace_hw_hnode(struct tcf_proto *tp, struct tc_u_hnode *h,
504 				u32 flags, struct netlink_ext_ack *extack)
505 {
506 	struct tcf_block *block = tp->chain->block;
507 	struct tc_cls_u32_offload cls_u32 = {};
508 	bool skip_sw = tc_skip_sw(flags);
509 	bool offloaded = false;
510 	int err;
511 
512 	tc_cls_common_offload_init(&cls_u32.common, tp, flags, extack);
513 	cls_u32.command = TC_CLSU32_NEW_HNODE;
514 	cls_u32.hnode.divisor = h->divisor;
515 	cls_u32.hnode.handle = h->handle;
516 	cls_u32.hnode.prio = h->prio;
517 
518 	err = tc_setup_cb_call(block, TC_SETUP_CLSU32, &cls_u32, skip_sw, true);
519 	if (err < 0) {
520 		u32_clear_hw_hnode(tp, h, NULL);
521 		return err;
522 	} else if (err > 0) {
523 		offloaded = true;
524 	}
525 
526 	if (skip_sw && !offloaded)
527 		return -EINVAL;
528 
529 	return 0;
530 }
531 
u32_remove_hw_knode(struct tcf_proto * tp,struct tc_u_knode * n,struct netlink_ext_ack * extack)532 static void u32_remove_hw_knode(struct tcf_proto *tp, struct tc_u_knode *n,
533 				struct netlink_ext_ack *extack)
534 {
535 	struct tcf_block *block = tp->chain->block;
536 	struct tc_cls_u32_offload cls_u32 = {};
537 
538 	tc_cls_common_offload_init(&cls_u32.common, tp, n->flags, extack);
539 	cls_u32.command = TC_CLSU32_DELETE_KNODE;
540 	cls_u32.knode.handle = n->handle;
541 
542 	tc_setup_cb_destroy(block, tp, TC_SETUP_CLSU32, &cls_u32, false,
543 			    &n->flags, &n->in_hw_count, true);
544 }
545 
u32_replace_hw_knode(struct tcf_proto * tp,struct tc_u_knode * n,u32 flags,struct netlink_ext_ack * extack)546 static int u32_replace_hw_knode(struct tcf_proto *tp, struct tc_u_knode *n,
547 				u32 flags, struct netlink_ext_ack *extack)
548 {
549 	struct tc_u_hnode *ht = rtnl_dereference(n->ht_down);
550 	struct tcf_block *block = tp->chain->block;
551 	struct tc_cls_u32_offload cls_u32 = {};
552 	bool skip_sw = tc_skip_sw(flags);
553 	int err;
554 
555 	tc_cls_common_offload_init(&cls_u32.common, tp, flags, extack);
556 	cls_u32.command = TC_CLSU32_REPLACE_KNODE;
557 	cls_u32.knode.handle = n->handle;
558 	cls_u32.knode.fshift = n->fshift;
559 #ifdef CONFIG_CLS_U32_MARK
560 	cls_u32.knode.val = n->val;
561 	cls_u32.knode.mask = n->mask;
562 #else
563 	cls_u32.knode.val = 0;
564 	cls_u32.knode.mask = 0;
565 #endif
566 	cls_u32.knode.sel = &n->sel;
567 	cls_u32.knode.res = &n->res;
568 	cls_u32.knode.exts = &n->exts;
569 	if (n->ht_down)
570 		cls_u32.knode.link_handle = ht->handle;
571 
572 	err = tc_setup_cb_add(block, tp, TC_SETUP_CLSU32, &cls_u32, skip_sw,
573 			      &n->flags, &n->in_hw_count, true);
574 	if (err) {
575 		u32_remove_hw_knode(tp, n, NULL);
576 		return err;
577 	}
578 
579 	if (skip_sw && !(n->flags & TCA_CLS_FLAGS_IN_HW))
580 		return -EINVAL;
581 
582 	return 0;
583 }
584 
u32_clear_hnode(struct tcf_proto * tp,struct tc_u_hnode * ht,struct netlink_ext_ack * extack)585 static void u32_clear_hnode(struct tcf_proto *tp, struct tc_u_hnode *ht,
586 			    struct netlink_ext_ack *extack)
587 {
588 	struct tc_u_common *tp_c = tp->data;
589 	struct tc_u_knode *n;
590 	unsigned int h;
591 
592 	for (h = 0; h <= ht->divisor; h++) {
593 		while ((n = rtnl_dereference(ht->ht[h])) != NULL) {
594 			RCU_INIT_POINTER(ht->ht[h],
595 					 rtnl_dereference(n->next));
596 			tp_c->knodes--;
597 			tcf_unbind_filter(tp, &n->res);
598 			u32_remove_hw_knode(tp, n, extack);
599 			idr_remove(&ht->handle_idr, n->handle);
600 			if (tcf_exts_get_net(&n->exts))
601 				tcf_queue_work(&n->rwork, u32_delete_key_freepf_work);
602 			else
603 				u32_destroy_key(n, true);
604 		}
605 	}
606 }
607 
u32_destroy_hnode(struct tcf_proto * tp,struct tc_u_hnode * ht,struct netlink_ext_ack * extack)608 static int u32_destroy_hnode(struct tcf_proto *tp, struct tc_u_hnode *ht,
609 			     struct netlink_ext_ack *extack)
610 {
611 	struct tc_u_common *tp_c = tp->data;
612 	struct tc_u_hnode __rcu **hn;
613 	struct tc_u_hnode *phn;
614 
615 	u32_clear_hnode(tp, ht, extack);
616 
617 	hn = &tp_c->hlist;
618 	for (phn = rtnl_dereference(*hn);
619 	     phn;
620 	     hn = &phn->next, phn = rtnl_dereference(*hn)) {
621 		if (phn == ht) {
622 			u32_clear_hw_hnode(tp, ht, extack);
623 			idr_destroy(&ht->handle_idr);
624 			idr_remove(&tp_c->handle_idr, handle2id(ht->handle));
625 			RCU_INIT_POINTER(*hn, ht->next);
626 			kfree_rcu(ht, rcu);
627 			return 0;
628 		}
629 	}
630 
631 	return -ENOENT;
632 }
633 
u32_destroy(struct tcf_proto * tp,bool rtnl_held,struct netlink_ext_ack * extack)634 static void u32_destroy(struct tcf_proto *tp, bool rtnl_held,
635 			struct netlink_ext_ack *extack)
636 {
637 	struct tc_u_common *tp_c = tp->data;
638 	struct tc_u_hnode *root_ht = rtnl_dereference(tp->root);
639 
640 	WARN_ON(root_ht == NULL);
641 
642 	if (root_ht && refcount_dec_and_test(&root_ht->refcnt))
643 		u32_destroy_hnode(tp, root_ht, extack);
644 
645 	if (refcount_dec_and_test(&tp_c->refcnt)) {
646 		struct tc_u_hnode *ht;
647 
648 		hlist_del(&tp_c->hnode);
649 
650 		while ((ht = rtnl_dereference(tp_c->hlist)) != NULL) {
651 			u32_clear_hnode(tp, ht, extack);
652 			RCU_INIT_POINTER(tp_c->hlist, ht->next);
653 
654 			/* u32_destroy_key() will later free ht for us, if it's
655 			 * still referenced by some knode
656 			 */
657 			if (refcount_dec_and_test(&ht->refcnt))
658 				kfree_rcu(ht, rcu);
659 		}
660 
661 		idr_destroy(&tp_c->handle_idr);
662 		kfree(tp_c);
663 	}
664 
665 	tp->data = NULL;
666 }
667 
u32_delete(struct tcf_proto * tp,void * arg,bool * last,bool rtnl_held,struct netlink_ext_ack * extack)668 static int u32_delete(struct tcf_proto *tp, void *arg, bool *last,
669 		      bool rtnl_held, struct netlink_ext_ack *extack)
670 {
671 	struct tc_u_hnode *ht = arg;
672 	struct tc_u_common *tp_c = tp->data;
673 	int ret = 0;
674 
675 	if (TC_U32_KEY(ht->handle)) {
676 		u32_remove_hw_knode(tp, (struct tc_u_knode *)ht, extack);
677 		ret = u32_delete_key(tp, (struct tc_u_knode *)ht);
678 		goto out;
679 	}
680 
681 	if (ht->is_root) {
682 		NL_SET_ERR_MSG_MOD(extack, "Not allowed to delete root node");
683 		return -EINVAL;
684 	}
685 
686 	if (refcount_dec_if_one(&ht->refcnt)) {
687 		u32_destroy_hnode(tp, ht, extack);
688 	} else {
689 		NL_SET_ERR_MSG_MOD(extack, "Can not delete in-use filter");
690 		return -EBUSY;
691 	}
692 
693 out:
694 	*last = refcount_read(&tp_c->refcnt) == 1 && tp_c->knodes == 0;
695 	return ret;
696 }
697 
gen_new_kid(struct tc_u_hnode * ht,u32 htid)698 static u32 gen_new_kid(struct tc_u_hnode *ht, u32 htid)
699 {
700 	u32 index = htid | 0x800;
701 	u32 max = htid | 0xFFF;
702 
703 	if (idr_alloc_u32(&ht->handle_idr, NULL, &index, max, GFP_KERNEL)) {
704 		index = htid + 1;
705 		if (idr_alloc_u32(&ht->handle_idr, NULL, &index, max,
706 				 GFP_KERNEL))
707 			index = max;
708 	}
709 
710 	return index;
711 }
712 
713 static const struct nla_policy u32_policy[TCA_U32_MAX + 1] = {
714 	[TCA_U32_CLASSID]	= { .type = NLA_U32 },
715 	[TCA_U32_HASH]		= { .type = NLA_U32 },
716 	[TCA_U32_LINK]		= { .type = NLA_U32 },
717 	[TCA_U32_DIVISOR]	= { .type = NLA_U32 },
718 	[TCA_U32_SEL]		= { .len = sizeof(struct tc_u32_sel) },
719 	[TCA_U32_INDEV]		= { .type = NLA_STRING, .len = IFNAMSIZ },
720 	[TCA_U32_MARK]		= { .len = sizeof(struct tc_u32_mark) },
721 	[TCA_U32_FLAGS]		= { .type = NLA_U32 },
722 };
723 
u32_unbind_filter(struct tcf_proto * tp,struct tc_u_knode * n,struct nlattr ** tb)724 static void u32_unbind_filter(struct tcf_proto *tp, struct tc_u_knode *n,
725 			      struct nlattr **tb)
726 {
727 	if (tb[TCA_U32_CLASSID])
728 		tcf_unbind_filter(tp, &n->res);
729 }
730 
u32_bind_filter(struct tcf_proto * tp,struct tc_u_knode * n,unsigned long base,struct nlattr ** tb)731 static void u32_bind_filter(struct tcf_proto *tp, struct tc_u_knode *n,
732 			    unsigned long base, struct nlattr **tb)
733 {
734 	if (tb[TCA_U32_CLASSID]) {
735 		n->res.classid = nla_get_u32(tb[TCA_U32_CLASSID]);
736 		tcf_bind_filter(tp, &n->res, base);
737 	}
738 }
739 
u32_set_parms(struct net * net,struct tcf_proto * tp,struct tc_u_knode * n,struct nlattr ** tb,struct nlattr * est,u32 flags,u32 fl_flags,struct netlink_ext_ack * extack)740 static int u32_set_parms(struct net *net, struct tcf_proto *tp,
741 			 struct tc_u_knode *n, struct nlattr **tb,
742 			 struct nlattr *est, u32 flags, u32 fl_flags,
743 			 struct netlink_ext_ack *extack)
744 {
745 	int err, ifindex = -1;
746 
747 	err = tcf_exts_validate_ex(net, tp, tb, est, &n->exts, flags,
748 				   fl_flags, extack);
749 	if (err < 0)
750 		return err;
751 
752 	if (tb[TCA_U32_INDEV]) {
753 		ifindex = tcf_change_indev(net, tb[TCA_U32_INDEV], extack);
754 		if (ifindex < 0)
755 			return -EINVAL;
756 	}
757 
758 	if (tb[TCA_U32_LINK]) {
759 		u32 handle = nla_get_u32(tb[TCA_U32_LINK]);
760 		struct tc_u_hnode *ht_down = NULL, *ht_old;
761 
762 		if (TC_U32_KEY(handle)) {
763 			NL_SET_ERR_MSG_MOD(extack, "u32 Link handle must be a hash table");
764 			return -EINVAL;
765 		}
766 
767 		if (handle) {
768 			ht_down = u32_lookup_ht(tp->data, handle);
769 
770 			if (!ht_down) {
771 				NL_SET_ERR_MSG_MOD(extack, "Link hash table not found");
772 				return -EINVAL;
773 			}
774 			if (ht_down->is_root) {
775 				NL_SET_ERR_MSG_MOD(extack, "Not linking to root node");
776 				return -EINVAL;
777 			}
778 			refcount_inc(&ht_down->refcnt);
779 		}
780 
781 		ht_old = rtnl_dereference(n->ht_down);
782 		rcu_assign_pointer(n->ht_down, ht_down);
783 
784 		if (ht_old)
785 			refcount_dec(&ht_old->refcnt);
786 	}
787 
788 	if (ifindex >= 0)
789 		n->ifindex = ifindex;
790 
791 	return 0;
792 }
793 
u32_replace_knode(struct tcf_proto * tp,struct tc_u_common * tp_c,struct tc_u_knode * n)794 static void u32_replace_knode(struct tcf_proto *tp, struct tc_u_common *tp_c,
795 			      struct tc_u_knode *n)
796 {
797 	struct tc_u_knode __rcu **ins;
798 	struct tc_u_knode *pins;
799 	struct tc_u_hnode *ht;
800 
801 	if (TC_U32_HTID(n->handle) == TC_U32_ROOT)
802 		ht = rtnl_dereference(tp->root);
803 	else
804 		ht = u32_lookup_ht(tp_c, TC_U32_HTID(n->handle));
805 
806 	ins = &ht->ht[TC_U32_HASH(n->handle)];
807 
808 	/* The node must always exist for it to be replaced if this is not the
809 	 * case then something went very wrong elsewhere.
810 	 */
811 	for (pins = rtnl_dereference(*ins); ;
812 	     ins = &pins->next, pins = rtnl_dereference(*ins))
813 		if (pins->handle == n->handle)
814 			break;
815 
816 	idr_replace(&ht->handle_idr, n, n->handle);
817 	RCU_INIT_POINTER(n->next, pins->next);
818 	rcu_assign_pointer(*ins, n);
819 }
820 
u32_init_knode(struct net * net,struct tcf_proto * tp,struct tc_u_knode * n)821 static struct tc_u_knode *u32_init_knode(struct net *net, struct tcf_proto *tp,
822 					 struct tc_u_knode *n)
823 {
824 	struct tc_u_hnode *ht = rtnl_dereference(n->ht_down);
825 	struct tc_u32_sel *s = &n->sel;
826 	struct tc_u_knode *new;
827 
828 	new = kzalloc(struct_size(new, sel.keys, s->nkeys), GFP_KERNEL);
829 	if (!new)
830 		return NULL;
831 
832 	RCU_INIT_POINTER(new->next, n->next);
833 	new->handle = n->handle;
834 	RCU_INIT_POINTER(new->ht_up, n->ht_up);
835 
836 	new->ifindex = n->ifindex;
837 	new->fshift = n->fshift;
838 	new->flags = n->flags;
839 	RCU_INIT_POINTER(new->ht_down, ht);
840 
841 #ifdef CONFIG_CLS_U32_PERF
842 	/* Statistics may be incremented by readers during update
843 	 * so we must keep them in tact. When the node is later destroyed
844 	 * a special destroy call must be made to not free the pf memory.
845 	 */
846 	new->pf = n->pf;
847 #endif
848 
849 #ifdef CONFIG_CLS_U32_MARK
850 	new->val = n->val;
851 	new->mask = n->mask;
852 	/* Similarly success statistics must be moved as pointers */
853 	new->pcpu_success = n->pcpu_success;
854 #endif
855 	memcpy(&new->sel, s, struct_size(s, keys, s->nkeys));
856 
857 	if (tcf_exts_init(&new->exts, net, TCA_U32_ACT, TCA_U32_POLICE)) {
858 		kfree(new);
859 		return NULL;
860 	}
861 
862 	/* bump reference count as long as we hold pointer to structure */
863 	if (ht)
864 		refcount_inc(&ht->refcnt);
865 
866 	return new;
867 }
868 
u32_change(struct net * net,struct sk_buff * in_skb,struct tcf_proto * tp,unsigned long base,u32 handle,struct nlattr ** tca,void ** arg,u32 flags,struct netlink_ext_ack * extack)869 static int u32_change(struct net *net, struct sk_buff *in_skb,
870 		      struct tcf_proto *tp, unsigned long base, u32 handle,
871 		      struct nlattr **tca, void **arg, u32 flags,
872 		      struct netlink_ext_ack *extack)
873 {
874 	struct tc_u_common *tp_c = tp->data;
875 	struct tc_u_hnode *ht;
876 	struct tc_u_knode *n;
877 	struct tc_u32_sel *s;
878 	struct nlattr *opt = tca[TCA_OPTIONS];
879 	struct nlattr *tb[TCA_U32_MAX + 1];
880 	u32 htid, userflags = 0;
881 	size_t sel_size;
882 	int err;
883 
884 	if (!opt) {
885 		if (handle) {
886 			NL_SET_ERR_MSG_MOD(extack, "Filter handle requires options");
887 			return -EINVAL;
888 		} else {
889 			return 0;
890 		}
891 	}
892 
893 	err = nla_parse_nested_deprecated(tb, TCA_U32_MAX, opt, u32_policy,
894 					  extack);
895 	if (err < 0)
896 		return err;
897 
898 	if (tb[TCA_U32_FLAGS]) {
899 		userflags = nla_get_u32(tb[TCA_U32_FLAGS]);
900 		if (!tc_flags_valid(userflags)) {
901 			NL_SET_ERR_MSG_MOD(extack, "Invalid filter flags");
902 			return -EINVAL;
903 		}
904 	}
905 
906 	n = *arg;
907 	if (n) {
908 		struct tc_u_knode *new;
909 
910 		if (TC_U32_KEY(n->handle) == 0) {
911 			NL_SET_ERR_MSG_MOD(extack, "Key node id cannot be zero");
912 			return -EINVAL;
913 		}
914 
915 		if ((n->flags ^ userflags) &
916 		    ~(TCA_CLS_FLAGS_IN_HW | TCA_CLS_FLAGS_NOT_IN_HW)) {
917 			NL_SET_ERR_MSG_MOD(extack, "Key node flags do not match passed flags");
918 			return -EINVAL;
919 		}
920 
921 		new = u32_init_knode(net, tp, n);
922 		if (!new)
923 			return -ENOMEM;
924 
925 		err = u32_set_parms(net, tp, new, tb, tca[TCA_RATE],
926 				    flags, new->flags, extack);
927 
928 		if (err) {
929 			__u32_destroy_key(new);
930 			return err;
931 		}
932 
933 		u32_bind_filter(tp, new, base, tb);
934 
935 		err = u32_replace_hw_knode(tp, new, flags, extack);
936 		if (err) {
937 			u32_unbind_filter(tp, new, tb);
938 
939 			if (tb[TCA_U32_LINK]) {
940 				struct tc_u_hnode *ht_old;
941 
942 				ht_old = rtnl_dereference(n->ht_down);
943 				if (ht_old)
944 					refcount_inc(&ht_old->refcnt);
945 			}
946 			__u32_destroy_key(new);
947 			return err;
948 		}
949 
950 		if (!tc_in_hw(new->flags))
951 			new->flags |= TCA_CLS_FLAGS_NOT_IN_HW;
952 
953 		tcf_proto_update_usesw(tp, new->flags);
954 
955 		u32_replace_knode(tp, tp_c, new);
956 		tcf_unbind_filter(tp, &n->res);
957 		tcf_exts_get_net(&n->exts);
958 		tcf_queue_work(&n->rwork, u32_delete_key_work);
959 		return 0;
960 	}
961 
962 	if (tb[TCA_U32_DIVISOR]) {
963 		unsigned int divisor = nla_get_u32(tb[TCA_U32_DIVISOR]);
964 
965 		if (!is_power_of_2(divisor)) {
966 			NL_SET_ERR_MSG_MOD(extack, "Divisor is not a power of 2");
967 			return -EINVAL;
968 		}
969 		if (divisor-- > 0x100) {
970 			NL_SET_ERR_MSG_MOD(extack, "Exceeded maximum 256 hash buckets");
971 			return -EINVAL;
972 		}
973 		if (TC_U32_KEY(handle)) {
974 			NL_SET_ERR_MSG_MOD(extack, "Divisor can only be used on a hash table");
975 			return -EINVAL;
976 		}
977 		ht = kzalloc(struct_size(ht, ht, divisor + 1), GFP_KERNEL);
978 		if (ht == NULL)
979 			return -ENOBUFS;
980 		if (handle == 0) {
981 			handle = gen_new_htid(tp->data, ht);
982 			if (handle == 0) {
983 				kfree(ht);
984 				return -ENOMEM;
985 			}
986 		} else {
987 			err = idr_alloc_u32(&tp_c->handle_idr, ht, &handle,
988 					    handle, GFP_KERNEL);
989 			if (err) {
990 				kfree(ht);
991 				return err;
992 			}
993 		}
994 		refcount_set(&ht->refcnt, 1);
995 		ht->divisor = divisor;
996 		ht->handle = handle;
997 		ht->prio = tp->prio;
998 		idr_init(&ht->handle_idr);
999 		ht->flags = userflags;
1000 
1001 		err = u32_replace_hw_hnode(tp, ht, userflags, extack);
1002 		if (err) {
1003 			idr_remove(&tp_c->handle_idr, handle2id(handle));
1004 			kfree(ht);
1005 			return err;
1006 		}
1007 
1008 		RCU_INIT_POINTER(ht->next, tp_c->hlist);
1009 		rcu_assign_pointer(tp_c->hlist, ht);
1010 		*arg = ht;
1011 
1012 		return 0;
1013 	}
1014 
1015 	if (tb[TCA_U32_HASH]) {
1016 		htid = nla_get_u32(tb[TCA_U32_HASH]);
1017 		if (TC_U32_HTID(htid) == TC_U32_ROOT) {
1018 			ht = rtnl_dereference(tp->root);
1019 			htid = ht->handle;
1020 		} else {
1021 			ht = u32_lookup_ht(tp->data, TC_U32_HTID(htid));
1022 			if (!ht) {
1023 				NL_SET_ERR_MSG_MOD(extack, "Specified hash table not found");
1024 				return -EINVAL;
1025 			}
1026 		}
1027 	} else {
1028 		ht = rtnl_dereference(tp->root);
1029 		htid = ht->handle;
1030 	}
1031 
1032 	if (ht->divisor < TC_U32_HASH(htid)) {
1033 		NL_SET_ERR_MSG_MOD(extack, "Specified hash table buckets exceed configured value");
1034 		return -EINVAL;
1035 	}
1036 
1037 	/* At this point, we need to derive the new handle that will be used to
1038 	 * uniquely map the identity of this table match entry. The
1039 	 * identity of the entry that we need to construct is 32 bits made of:
1040 	 *     htid(12b):bucketid(8b):node/entryid(12b)
1041 	 *
1042 	 * At this point _we have the table(ht)_ in which we will insert this
1043 	 * entry. We carry the table's id in variable "htid".
1044 	 * Note that earlier code picked the ht selection either by a) the user
1045 	 * providing the htid specified via TCA_U32_HASH attribute or b) when
1046 	 * no such attribute is passed then the root ht, is default to at ID
1047 	 * 0x[800][00][000]. Rule: the root table has a single bucket with ID 0.
1048 	 * If OTOH the user passed us the htid, they may also pass a bucketid of
1049 	 * choice. 0 is fine. For example a user htid is 0x[600][01][000] it is
1050 	 * indicating hash bucketid of 1. Rule: the entry/node ID _cannot_ be
1051 	 * passed via the htid, so even if it was non-zero it will be ignored.
1052 	 *
1053 	 * We may also have a handle, if the user passed one. The handle also
1054 	 * carries the same addressing of htid(12b):bucketid(8b):node/entryid(12b).
1055 	 * Rule: the bucketid on the handle is ignored even if one was passed;
1056 	 * rather the value on "htid" is always assumed to be the bucketid.
1057 	 */
1058 	if (handle) {
1059 		/* Rule: The htid from handle and tableid from htid must match */
1060 		if (TC_U32_HTID(handle) && TC_U32_HTID(handle ^ htid)) {
1061 			NL_SET_ERR_MSG_MOD(extack, "Handle specified hash table address mismatch");
1062 			return -EINVAL;
1063 		}
1064 		/* Ok, so far we have a valid htid(12b):bucketid(8b) but we
1065 		 * need to finalize the table entry identification with the last
1066 		 * part - the node/entryid(12b)). Rule: Nodeid _cannot be 0_ for
1067 		 * entries. Rule: nodeid of 0 is reserved only for tables(see
1068 		 * earlier code which processes TC_U32_DIVISOR attribute).
1069 		 * Rule: The nodeid can only be derived from the handle (and not
1070 		 * htid).
1071 		 * Rule: if the handle specified zero for the node id example
1072 		 * 0x60000000, then pick a new nodeid from the pool of IDs
1073 		 * this hash table has been allocating from.
1074 		 * If OTOH it is specified (i.e for example the user passed a
1075 		 * handle such as 0x60000123), then we use it generate our final
1076 		 * handle which is used to uniquely identify the match entry.
1077 		 */
1078 		if (!TC_U32_NODE(handle)) {
1079 			handle = gen_new_kid(ht, htid);
1080 		} else {
1081 			handle = htid | TC_U32_NODE(handle);
1082 			err = idr_alloc_u32(&ht->handle_idr, NULL, &handle,
1083 					    handle, GFP_KERNEL);
1084 			if (err)
1085 				return err;
1086 		}
1087 	} else {
1088 		/* The user did not give us a handle; lets just generate one
1089 		 * from the table's pool of nodeids.
1090 		 */
1091 		handle = gen_new_kid(ht, htid);
1092 	}
1093 
1094 	if (tb[TCA_U32_SEL] == NULL) {
1095 		NL_SET_ERR_MSG_MOD(extack, "Selector not specified");
1096 		err = -EINVAL;
1097 		goto erridr;
1098 	}
1099 
1100 	s = nla_data(tb[TCA_U32_SEL]);
1101 	sel_size = struct_size(s, keys, s->nkeys);
1102 	if (nla_len(tb[TCA_U32_SEL]) < sel_size) {
1103 		err = -EINVAL;
1104 		goto erridr;
1105 	}
1106 
1107 	n = kzalloc(struct_size(n, sel.keys, s->nkeys), GFP_KERNEL);
1108 	if (n == NULL) {
1109 		err = -ENOBUFS;
1110 		goto erridr;
1111 	}
1112 
1113 #ifdef CONFIG_CLS_U32_PERF
1114 	n->pf = __alloc_percpu(struct_size(n->pf, kcnts, s->nkeys),
1115 			       __alignof__(struct tc_u32_pcnt));
1116 	if (!n->pf) {
1117 		err = -ENOBUFS;
1118 		goto errfree;
1119 	}
1120 #endif
1121 
1122 	unsafe_memcpy(&n->sel, s, sel_size,
1123 		      /* A composite flex-array structure destination,
1124 		       * which was correctly sized with struct_size(),
1125 		       * bounds-checked against nla_len(), and allocated
1126 		       * above. */);
1127 	RCU_INIT_POINTER(n->ht_up, ht);
1128 	n->handle = handle;
1129 	n->fshift = s->hmask ? ffs(ntohl(s->hmask)) - 1 : 0;
1130 	n->flags = userflags;
1131 
1132 	err = tcf_exts_init(&n->exts, net, TCA_U32_ACT, TCA_U32_POLICE);
1133 	if (err < 0)
1134 		goto errout;
1135 
1136 #ifdef CONFIG_CLS_U32_MARK
1137 	n->pcpu_success = alloc_percpu(u32);
1138 	if (!n->pcpu_success) {
1139 		err = -ENOMEM;
1140 		goto errout;
1141 	}
1142 
1143 	if (tb[TCA_U32_MARK]) {
1144 		struct tc_u32_mark *mark;
1145 
1146 		mark = nla_data(tb[TCA_U32_MARK]);
1147 		n->val = mark->val;
1148 		n->mask = mark->mask;
1149 	}
1150 #endif
1151 
1152 	err = u32_set_parms(net, tp, n, tb, tca[TCA_RATE],
1153 			    flags, n->flags, extack);
1154 
1155 	u32_bind_filter(tp, n, base, tb);
1156 
1157 	if (err == 0) {
1158 		struct tc_u_knode __rcu **ins;
1159 		struct tc_u_knode *pins;
1160 
1161 		err = u32_replace_hw_knode(tp, n, flags, extack);
1162 		if (err)
1163 			goto errunbind;
1164 
1165 		if (!tc_in_hw(n->flags))
1166 			n->flags |= TCA_CLS_FLAGS_NOT_IN_HW;
1167 
1168 		tcf_proto_update_usesw(tp, n->flags);
1169 
1170 		ins = &ht->ht[TC_U32_HASH(handle)];
1171 		for (pins = rtnl_dereference(*ins); pins;
1172 		     ins = &pins->next, pins = rtnl_dereference(*ins))
1173 			if (TC_U32_NODE(handle) < TC_U32_NODE(pins->handle))
1174 				break;
1175 
1176 		RCU_INIT_POINTER(n->next, pins);
1177 		rcu_assign_pointer(*ins, n);
1178 		tp_c->knodes++;
1179 		*arg = n;
1180 		return 0;
1181 	}
1182 
1183 errunbind:
1184 	u32_unbind_filter(tp, n, tb);
1185 
1186 #ifdef CONFIG_CLS_U32_MARK
1187 	free_percpu(n->pcpu_success);
1188 #endif
1189 
1190 errout:
1191 	tcf_exts_destroy(&n->exts);
1192 #ifdef CONFIG_CLS_U32_PERF
1193 errfree:
1194 	free_percpu(n->pf);
1195 #endif
1196 	kfree(n);
1197 erridr:
1198 	idr_remove(&ht->handle_idr, handle);
1199 	return err;
1200 }
1201 
u32_walk(struct tcf_proto * tp,struct tcf_walker * arg,bool rtnl_held)1202 static void u32_walk(struct tcf_proto *tp, struct tcf_walker *arg,
1203 		     bool rtnl_held)
1204 {
1205 	struct tc_u_common *tp_c = tp->data;
1206 	struct tc_u_hnode *ht;
1207 	struct tc_u_knode *n;
1208 	unsigned int h;
1209 
1210 	if (arg->stop)
1211 		return;
1212 
1213 	for (ht = rtnl_dereference(tp_c->hlist);
1214 	     ht;
1215 	     ht = rtnl_dereference(ht->next)) {
1216 		if (ht->prio != tp->prio)
1217 			continue;
1218 
1219 		if (!tc_cls_stats_dump(tp, arg, ht))
1220 			return;
1221 
1222 		for (h = 0; h <= ht->divisor; h++) {
1223 			for (n = rtnl_dereference(ht->ht[h]);
1224 			     n;
1225 			     n = rtnl_dereference(n->next)) {
1226 				if (!tc_cls_stats_dump(tp, arg, n))
1227 					return;
1228 			}
1229 		}
1230 	}
1231 }
1232 
u32_reoffload_hnode(struct tcf_proto * tp,struct tc_u_hnode * ht,bool add,flow_setup_cb_t * cb,void * cb_priv,struct netlink_ext_ack * extack)1233 static int u32_reoffload_hnode(struct tcf_proto *tp, struct tc_u_hnode *ht,
1234 			       bool add, flow_setup_cb_t *cb, void *cb_priv,
1235 			       struct netlink_ext_ack *extack)
1236 {
1237 	struct tc_cls_u32_offload cls_u32 = {};
1238 	int err;
1239 
1240 	tc_cls_common_offload_init(&cls_u32.common, tp, ht->flags, extack);
1241 	cls_u32.command = add ? TC_CLSU32_NEW_HNODE : TC_CLSU32_DELETE_HNODE;
1242 	cls_u32.hnode.divisor = ht->divisor;
1243 	cls_u32.hnode.handle = ht->handle;
1244 	cls_u32.hnode.prio = ht->prio;
1245 
1246 	err = cb(TC_SETUP_CLSU32, &cls_u32, cb_priv);
1247 	if (err && add && tc_skip_sw(ht->flags))
1248 		return err;
1249 
1250 	return 0;
1251 }
1252 
u32_reoffload_knode(struct tcf_proto * tp,struct tc_u_knode * n,bool add,flow_setup_cb_t * cb,void * cb_priv,struct netlink_ext_ack * extack)1253 static int u32_reoffload_knode(struct tcf_proto *tp, struct tc_u_knode *n,
1254 			       bool add, flow_setup_cb_t *cb, void *cb_priv,
1255 			       struct netlink_ext_ack *extack)
1256 {
1257 	struct tc_u_hnode *ht = rtnl_dereference(n->ht_down);
1258 	struct tcf_block *block = tp->chain->block;
1259 	struct tc_cls_u32_offload cls_u32 = {};
1260 
1261 	tc_cls_common_offload_init(&cls_u32.common, tp, n->flags, extack);
1262 	cls_u32.command = add ?
1263 		TC_CLSU32_REPLACE_KNODE : TC_CLSU32_DELETE_KNODE;
1264 	cls_u32.knode.handle = n->handle;
1265 
1266 	if (add) {
1267 		cls_u32.knode.fshift = n->fshift;
1268 #ifdef CONFIG_CLS_U32_MARK
1269 		cls_u32.knode.val = n->val;
1270 		cls_u32.knode.mask = n->mask;
1271 #else
1272 		cls_u32.knode.val = 0;
1273 		cls_u32.knode.mask = 0;
1274 #endif
1275 		cls_u32.knode.sel = &n->sel;
1276 		cls_u32.knode.res = &n->res;
1277 		cls_u32.knode.exts = &n->exts;
1278 		if (n->ht_down)
1279 			cls_u32.knode.link_handle = ht->handle;
1280 	}
1281 
1282 	return tc_setup_cb_reoffload(block, tp, add, cb, TC_SETUP_CLSU32,
1283 				     &cls_u32, cb_priv, &n->flags,
1284 				     &n->in_hw_count);
1285 }
1286 
u32_reoffload(struct tcf_proto * tp,bool add,flow_setup_cb_t * cb,void * cb_priv,struct netlink_ext_ack * extack)1287 static int u32_reoffload(struct tcf_proto *tp, bool add, flow_setup_cb_t *cb,
1288 			 void *cb_priv, struct netlink_ext_ack *extack)
1289 {
1290 	struct tc_u_common *tp_c = tp->data;
1291 	struct tc_u_hnode *ht;
1292 	struct tc_u_knode *n;
1293 	unsigned int h;
1294 	int err;
1295 
1296 	for (ht = rtnl_dereference(tp_c->hlist);
1297 	     ht;
1298 	     ht = rtnl_dereference(ht->next)) {
1299 		if (ht->prio != tp->prio)
1300 			continue;
1301 
1302 		/* When adding filters to a new dev, try to offload the
1303 		 * hashtable first. When removing, do the filters before the
1304 		 * hashtable.
1305 		 */
1306 		if (add && !tc_skip_hw(ht->flags)) {
1307 			err = u32_reoffload_hnode(tp, ht, add, cb, cb_priv,
1308 						  extack);
1309 			if (err)
1310 				return err;
1311 		}
1312 
1313 		for (h = 0; h <= ht->divisor; h++) {
1314 			for (n = rtnl_dereference(ht->ht[h]);
1315 			     n;
1316 			     n = rtnl_dereference(n->next)) {
1317 				if (tc_skip_hw(n->flags))
1318 					continue;
1319 
1320 				err = u32_reoffload_knode(tp, n, add, cb,
1321 							  cb_priv, extack);
1322 				if (err)
1323 					return err;
1324 			}
1325 		}
1326 
1327 		if (!add && !tc_skip_hw(ht->flags))
1328 			u32_reoffload_hnode(tp, ht, add, cb, cb_priv, extack);
1329 	}
1330 
1331 	return 0;
1332 }
1333 
u32_bind_class(void * fh,u32 classid,unsigned long cl,void * q,unsigned long base)1334 static void u32_bind_class(void *fh, u32 classid, unsigned long cl, void *q,
1335 			   unsigned long base)
1336 {
1337 	struct tc_u_knode *n = fh;
1338 
1339 	tc_cls_bind_class(classid, cl, q, &n->res, base);
1340 }
1341 
u32_dump(struct net * net,struct tcf_proto * tp,void * fh,struct sk_buff * skb,struct tcmsg * t,bool rtnl_held)1342 static int u32_dump(struct net *net, struct tcf_proto *tp, void *fh,
1343 		    struct sk_buff *skb, struct tcmsg *t, bool rtnl_held)
1344 {
1345 	struct tc_u_knode *n = fh;
1346 	struct tc_u_hnode *ht_up, *ht_down;
1347 	struct nlattr *nest;
1348 
1349 	if (n == NULL)
1350 		return skb->len;
1351 
1352 	t->tcm_handle = n->handle;
1353 
1354 	nest = nla_nest_start_noflag(skb, TCA_OPTIONS);
1355 	if (nest == NULL)
1356 		goto nla_put_failure;
1357 
1358 	if (TC_U32_KEY(n->handle) == 0) {
1359 		struct tc_u_hnode *ht = fh;
1360 		u32 divisor = ht->divisor + 1;
1361 
1362 		if (nla_put_u32(skb, TCA_U32_DIVISOR, divisor))
1363 			goto nla_put_failure;
1364 	} else {
1365 #ifdef CONFIG_CLS_U32_PERF
1366 		struct tc_u32_pcnt *gpf;
1367 		int cpu;
1368 #endif
1369 
1370 		if (nla_put(skb, TCA_U32_SEL, struct_size(&n->sel, keys, n->sel.nkeys),
1371 			    &n->sel))
1372 			goto nla_put_failure;
1373 
1374 		ht_up = rtnl_dereference(n->ht_up);
1375 		if (ht_up) {
1376 			u32 htid = n->handle & 0xFFFFF000;
1377 			if (nla_put_u32(skb, TCA_U32_HASH, htid))
1378 				goto nla_put_failure;
1379 		}
1380 		if (n->res.classid &&
1381 		    nla_put_u32(skb, TCA_U32_CLASSID, n->res.classid))
1382 			goto nla_put_failure;
1383 
1384 		ht_down = rtnl_dereference(n->ht_down);
1385 		if (ht_down &&
1386 		    nla_put_u32(skb, TCA_U32_LINK, ht_down->handle))
1387 			goto nla_put_failure;
1388 
1389 		if (n->flags && nla_put_u32(skb, TCA_U32_FLAGS, n->flags))
1390 			goto nla_put_failure;
1391 
1392 #ifdef CONFIG_CLS_U32_MARK
1393 		if ((n->val || n->mask)) {
1394 			struct tc_u32_mark mark = {.val = n->val,
1395 						   .mask = n->mask,
1396 						   .success = 0};
1397 			int cpum;
1398 
1399 			for_each_possible_cpu(cpum) {
1400 				__u32 cnt = *per_cpu_ptr(n->pcpu_success, cpum);
1401 
1402 				mark.success += cnt;
1403 			}
1404 
1405 			if (nla_put(skb, TCA_U32_MARK, sizeof(mark), &mark))
1406 				goto nla_put_failure;
1407 		}
1408 #endif
1409 
1410 		if (tcf_exts_dump(skb, &n->exts) < 0)
1411 			goto nla_put_failure;
1412 
1413 		if (n->ifindex) {
1414 			struct net_device *dev;
1415 			dev = __dev_get_by_index(net, n->ifindex);
1416 			if (dev && nla_put_string(skb, TCA_U32_INDEV, dev->name))
1417 				goto nla_put_failure;
1418 		}
1419 #ifdef CONFIG_CLS_U32_PERF
1420 		gpf = kzalloc(struct_size(gpf, kcnts, n->sel.nkeys), GFP_KERNEL);
1421 		if (!gpf)
1422 			goto nla_put_failure;
1423 
1424 		for_each_possible_cpu(cpu) {
1425 			int i;
1426 			struct tc_u32_pcnt *pf = per_cpu_ptr(n->pf, cpu);
1427 
1428 			gpf->rcnt += pf->rcnt;
1429 			gpf->rhit += pf->rhit;
1430 			for (i = 0; i < n->sel.nkeys; i++)
1431 				gpf->kcnts[i] += pf->kcnts[i];
1432 		}
1433 
1434 		if (nla_put_64bit(skb, TCA_U32_PCNT, struct_size(gpf, kcnts, n->sel.nkeys),
1435 				  gpf, TCA_U32_PAD)) {
1436 			kfree(gpf);
1437 			goto nla_put_failure;
1438 		}
1439 		kfree(gpf);
1440 #endif
1441 	}
1442 
1443 	nla_nest_end(skb, nest);
1444 
1445 	if (TC_U32_KEY(n->handle))
1446 		if (tcf_exts_dump_stats(skb, &n->exts) < 0)
1447 			goto nla_put_failure;
1448 	return skb->len;
1449 
1450 nla_put_failure:
1451 	nla_nest_cancel(skb, nest);
1452 	return -1;
1453 }
1454 
1455 static struct tcf_proto_ops cls_u32_ops __read_mostly = {
1456 	.kind		=	"u32",
1457 	.classify	=	u32_classify,
1458 	.init		=	u32_init,
1459 	.destroy	=	u32_destroy,
1460 	.get		=	u32_get,
1461 	.change		=	u32_change,
1462 	.delete		=	u32_delete,
1463 	.walk		=	u32_walk,
1464 	.reoffload	=	u32_reoffload,
1465 	.dump		=	u32_dump,
1466 	.bind_class	=	u32_bind_class,
1467 	.owner		=	THIS_MODULE,
1468 };
1469 MODULE_ALIAS_NET_CLS("u32");
1470 
init_u32(void)1471 static int __init init_u32(void)
1472 {
1473 	int i, ret;
1474 
1475 	pr_info("u32 classifier\n");
1476 #ifdef CONFIG_CLS_U32_PERF
1477 	pr_info("    Performance counters on\n");
1478 #endif
1479 	pr_info("    input device check on\n");
1480 #ifdef CONFIG_NET_CLS_ACT
1481 	pr_info("    Actions configured\n");
1482 #endif
1483 	tc_u_common_hash = kvmalloc_array(U32_HASH_SIZE,
1484 					  sizeof(struct hlist_head),
1485 					  GFP_KERNEL);
1486 	if (!tc_u_common_hash)
1487 		return -ENOMEM;
1488 
1489 	for (i = 0; i < U32_HASH_SIZE; i++)
1490 		INIT_HLIST_HEAD(&tc_u_common_hash[i]);
1491 
1492 	ret = register_tcf_proto_ops(&cls_u32_ops);
1493 	if (ret)
1494 		kvfree(tc_u_common_hash);
1495 	return ret;
1496 }
1497 
exit_u32(void)1498 static void __exit exit_u32(void)
1499 {
1500 	unregister_tcf_proto_ops(&cls_u32_ops);
1501 	kvfree(tc_u_common_hash);
1502 }
1503 
1504 module_init(init_u32)
1505 module_exit(exit_u32)
1506 MODULE_DESCRIPTION("Universal 32bit based TC Classifier");
1507 MODULE_LICENSE("GPL");
1508