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v5.4
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * net/sched/cls_route.c	ROUTE4 classifier.
  4 *
  5 * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
  6 */
  7
  8#include <linux/module.h>
  9#include <linux/slab.h>
 10#include <linux/types.h>
 11#include <linux/kernel.h>
 12#include <linux/string.h>
 13#include <linux/errno.h>
 14#include <linux/skbuff.h>
 15#include <net/dst.h>
 16#include <net/route.h>
 17#include <net/netlink.h>
 18#include <net/act_api.h>
 19#include <net/pkt_cls.h>
 
 20
 21/*
 22 * 1. For now we assume that route tags < 256.
 23 *    It allows to use direct table lookups, instead of hash tables.
 24 * 2. For now we assume that "from TAG" and "fromdev DEV" statements
 25 *    are mutually  exclusive.
 26 * 3. "to TAG from ANY" has higher priority, than "to ANY from XXX"
 27 */
 28struct route4_fastmap {
 29	struct route4_filter		*filter;
 30	u32				id;
 31	int				iif;
 32};
 33
 34struct route4_head {
 35	struct route4_fastmap		fastmap[16];
 36	struct route4_bucket __rcu	*table[256 + 1];
 37	struct rcu_head			rcu;
 38};
 39
 40struct route4_bucket {
 41	/* 16 FROM buckets + 16 IIF buckets + 1 wildcard bucket */
 42	struct route4_filter __rcu	*ht[16 + 16 + 1];
 43	struct rcu_head			rcu;
 44};
 45
 46struct route4_filter {
 47	struct route4_filter __rcu	*next;
 48	u32			id;
 49	int			iif;
 50
 51	struct tcf_result	res;
 52	struct tcf_exts		exts;
 53	u32			handle;
 54	struct route4_bucket	*bkt;
 55	struct tcf_proto	*tp;
 56	struct rcu_work		rwork;
 57};
 58
 59#define ROUTE4_FAILURE ((struct route4_filter *)(-1L))
 60
 61static inline int route4_fastmap_hash(u32 id, int iif)
 62{
 63	return id & 0xF;
 64}
 65
 66static DEFINE_SPINLOCK(fastmap_lock);
 67static void
 68route4_reset_fastmap(struct route4_head *head)
 69{
 70	spin_lock_bh(&fastmap_lock);
 71	memset(head->fastmap, 0, sizeof(head->fastmap));
 72	spin_unlock_bh(&fastmap_lock);
 73}
 74
 75static void
 76route4_set_fastmap(struct route4_head *head, u32 id, int iif,
 77		   struct route4_filter *f)
 78{
 79	int h = route4_fastmap_hash(id, iif);
 80
 81	/* fastmap updates must look atomic to aling id, iff, filter */
 82	spin_lock_bh(&fastmap_lock);
 83	head->fastmap[h].id = id;
 84	head->fastmap[h].iif = iif;
 85	head->fastmap[h].filter = f;
 86	spin_unlock_bh(&fastmap_lock);
 87}
 88
 89static inline int route4_hash_to(u32 id)
 90{
 91	return id & 0xFF;
 92}
 93
 94static inline int route4_hash_from(u32 id)
 95{
 96	return (id >> 16) & 0xF;
 97}
 98
 99static inline int route4_hash_iif(int iif)
100{
101	return 16 + ((iif >> 16) & 0xF);
102}
103
104static inline int route4_hash_wild(void)
105{
106	return 32;
107}
108
109#define ROUTE4_APPLY_RESULT()					\
110{								\
111	*res = f->res;						\
112	if (tcf_exts_has_actions(&f->exts)) {			\
113		int r = tcf_exts_exec(skb, &f->exts, res);	\
114		if (r < 0) {					\
115			dont_cache = 1;				\
116			continue;				\
117		}						\
118		return r;					\
119	} else if (!dont_cache)					\
120		route4_set_fastmap(head, id, iif, f);		\
121	return 0;						\
122}
123
124static int route4_classify(struct sk_buff *skb, const struct tcf_proto *tp,
125			   struct tcf_result *res)
 
126{
127	struct route4_head *head = rcu_dereference_bh(tp->root);
128	struct dst_entry *dst;
129	struct route4_bucket *b;
130	struct route4_filter *f;
131	u32 id, h;
132	int iif, dont_cache = 0;
133
134	dst = skb_dst(skb);
135	if (!dst)
136		goto failure;
137
138	id = dst->tclassid;
139
140	iif = inet_iif(skb);
141
142	h = route4_fastmap_hash(id, iif);
143
144	spin_lock(&fastmap_lock);
145	if (id == head->fastmap[h].id &&
146	    iif == head->fastmap[h].iif &&
147	    (f = head->fastmap[h].filter) != NULL) {
148		if (f == ROUTE4_FAILURE) {
149			spin_unlock(&fastmap_lock);
150			goto failure;
151		}
152
153		*res = f->res;
154		spin_unlock(&fastmap_lock);
155		return 0;
156	}
157	spin_unlock(&fastmap_lock);
158
159	h = route4_hash_to(id);
160
161restart:
162	b = rcu_dereference_bh(head->table[h]);
163	if (b) {
164		for (f = rcu_dereference_bh(b->ht[route4_hash_from(id)]);
165		     f;
166		     f = rcu_dereference_bh(f->next))
167			if (f->id == id)
168				ROUTE4_APPLY_RESULT();
169
170		for (f = rcu_dereference_bh(b->ht[route4_hash_iif(iif)]);
171		     f;
172		     f = rcu_dereference_bh(f->next))
173			if (f->iif == iif)
174				ROUTE4_APPLY_RESULT();
175
176		for (f = rcu_dereference_bh(b->ht[route4_hash_wild()]);
177		     f;
178		     f = rcu_dereference_bh(f->next))
179			ROUTE4_APPLY_RESULT();
180	}
181	if (h < 256) {
182		h = 256;
183		id &= ~0xFFFF;
184		goto restart;
185	}
186
187	if (!dont_cache)
188		route4_set_fastmap(head, id, iif, ROUTE4_FAILURE);
189failure:
190	return -1;
191}
192
193static inline u32 to_hash(u32 id)
194{
195	u32 h = id & 0xFF;
196
197	if (id & 0x8000)
198		h += 256;
199	return h;
200}
201
202static inline u32 from_hash(u32 id)
203{
204	id &= 0xFFFF;
205	if (id == 0xFFFF)
206		return 32;
207	if (!(id & 0x8000)) {
208		if (id > 255)
209			return 256;
210		return id & 0xF;
211	}
212	return 16 + (id & 0xF);
213}
214
215static void *route4_get(struct tcf_proto *tp, u32 handle)
216{
217	struct route4_head *head = rtnl_dereference(tp->root);
218	struct route4_bucket *b;
219	struct route4_filter *f;
220	unsigned int h1, h2;
221
222	h1 = to_hash(handle);
223	if (h1 > 256)
224		return NULL;
225
226	h2 = from_hash(handle >> 16);
227	if (h2 > 32)
228		return NULL;
229
230	b = rtnl_dereference(head->table[h1]);
231	if (b) {
232		for (f = rtnl_dereference(b->ht[h2]);
233		     f;
234		     f = rtnl_dereference(f->next))
235			if (f->handle == handle)
236				return f;
237	}
238	return NULL;
239}
240
241static int route4_init(struct tcf_proto *tp)
242{
243	struct route4_head *head;
244
245	head = kzalloc(sizeof(struct route4_head), GFP_KERNEL);
246	if (head == NULL)
247		return -ENOBUFS;
248
249	rcu_assign_pointer(tp->root, head);
250	return 0;
251}
252
253static void __route4_delete_filter(struct route4_filter *f)
254{
255	tcf_exts_destroy(&f->exts);
256	tcf_exts_put_net(&f->exts);
257	kfree(f);
258}
259
260static void route4_delete_filter_work(struct work_struct *work)
261{
262	struct route4_filter *f = container_of(to_rcu_work(work),
263					       struct route4_filter,
264					       rwork);
265	rtnl_lock();
266	__route4_delete_filter(f);
267	rtnl_unlock();
268}
269
270static void route4_queue_work(struct route4_filter *f)
271{
272	tcf_queue_work(&f->rwork, route4_delete_filter_work);
273}
274
275static void route4_destroy(struct tcf_proto *tp, bool rtnl_held,
276			   struct netlink_ext_ack *extack)
277{
278	struct route4_head *head = rtnl_dereference(tp->root);
279	int h1, h2;
280
281	if (head == NULL)
282		return;
283
284	for (h1 = 0; h1 <= 256; h1++) {
285		struct route4_bucket *b;
286
287		b = rtnl_dereference(head->table[h1]);
288		if (b) {
289			for (h2 = 0; h2 <= 32; h2++) {
290				struct route4_filter *f;
291
292				while ((f = rtnl_dereference(b->ht[h2])) != NULL) {
293					struct route4_filter *next;
294
295					next = rtnl_dereference(f->next);
296					RCU_INIT_POINTER(b->ht[h2], next);
297					tcf_unbind_filter(tp, &f->res);
298					if (tcf_exts_get_net(&f->exts))
299						route4_queue_work(f);
300					else
301						__route4_delete_filter(f);
302				}
303			}
304			RCU_INIT_POINTER(head->table[h1], NULL);
305			kfree_rcu(b, rcu);
306		}
307	}
308	kfree_rcu(head, rcu);
309}
310
311static int route4_delete(struct tcf_proto *tp, void *arg, bool *last,
312			 bool rtnl_held, struct netlink_ext_ack *extack)
313{
314	struct route4_head *head = rtnl_dereference(tp->root);
315	struct route4_filter *f = arg;
316	struct route4_filter __rcu **fp;
317	struct route4_filter *nf;
318	struct route4_bucket *b;
319	unsigned int h = 0;
320	int i, h1;
321
322	if (!head || !f)
323		return -EINVAL;
324
325	h = f->handle;
326	b = f->bkt;
327
328	fp = &b->ht[from_hash(h >> 16)];
329	for (nf = rtnl_dereference(*fp); nf;
330	     fp = &nf->next, nf = rtnl_dereference(*fp)) {
331		if (nf == f) {
332			/* unlink it */
333			RCU_INIT_POINTER(*fp, rtnl_dereference(f->next));
334
335			/* Remove any fastmap lookups that might ref filter
336			 * notice we unlink'd the filter so we can't get it
337			 * back in the fastmap.
338			 */
339			route4_reset_fastmap(head);
340
341			/* Delete it */
342			tcf_unbind_filter(tp, &f->res);
343			tcf_exts_get_net(&f->exts);
344			tcf_queue_work(&f->rwork, route4_delete_filter_work);
345
346			/* Strip RTNL protected tree */
347			for (i = 0; i <= 32; i++) {
348				struct route4_filter *rt;
349
350				rt = rtnl_dereference(b->ht[i]);
351				if (rt)
352					goto out;
353			}
354
355			/* OK, session has no flows */
356			RCU_INIT_POINTER(head->table[to_hash(h)], NULL);
357			kfree_rcu(b, rcu);
358			break;
359		}
360	}
361
362out:
363	*last = true;
364	for (h1 = 0; h1 <= 256; h1++) {
365		if (rcu_access_pointer(head->table[h1])) {
366			*last = false;
367			break;
368		}
369	}
370
371	return 0;
372}
373
374static const struct nla_policy route4_policy[TCA_ROUTE4_MAX + 1] = {
375	[TCA_ROUTE4_CLASSID]	= { .type = NLA_U32 },
376	[TCA_ROUTE4_TO]		= { .type = NLA_U32 },
377	[TCA_ROUTE4_FROM]	= { .type = NLA_U32 },
378	[TCA_ROUTE4_IIF]	= { .type = NLA_U32 },
379};
380
381static int route4_set_parms(struct net *net, struct tcf_proto *tp,
382			    unsigned long base, struct route4_filter *f,
383			    u32 handle, struct route4_head *head,
384			    struct nlattr **tb, struct nlattr *est, int new,
385			    bool ovr, struct netlink_ext_ack *extack)
386{
387	u32 id = 0, to = 0, nhandle = 0x8000;
388	struct route4_filter *fp;
389	unsigned int h1;
390	struct route4_bucket *b;
391	int err;
392
393	err = tcf_exts_validate(net, tp, tb, est, &f->exts, ovr, true, extack);
394	if (err < 0)
395		return err;
396
397	if (tb[TCA_ROUTE4_TO]) {
398		if (new && handle & 0x8000)
399			return -EINVAL;
400		to = nla_get_u32(tb[TCA_ROUTE4_TO]);
401		if (to > 0xFF)
402			return -EINVAL;
403		nhandle = to;
404	}
405
406	if (tb[TCA_ROUTE4_FROM]) {
407		if (tb[TCA_ROUTE4_IIF])
408			return -EINVAL;
409		id = nla_get_u32(tb[TCA_ROUTE4_FROM]);
410		if (id > 0xFF)
411			return -EINVAL;
412		nhandle |= id << 16;
413	} else if (tb[TCA_ROUTE4_IIF]) {
414		id = nla_get_u32(tb[TCA_ROUTE4_IIF]);
415		if (id > 0x7FFF)
416			return -EINVAL;
417		nhandle |= (id | 0x8000) << 16;
418	} else
419		nhandle |= 0xFFFF << 16;
420
421	if (handle && new) {
422		nhandle |= handle & 0x7F00;
423		if (nhandle != handle)
424			return -EINVAL;
425	}
426
 
 
 
 
 
427	h1 = to_hash(nhandle);
428	b = rtnl_dereference(head->table[h1]);
429	if (!b) {
430		b = kzalloc(sizeof(struct route4_bucket), GFP_KERNEL);
431		if (b == NULL)
432			return -ENOBUFS;
433
434		rcu_assign_pointer(head->table[h1], b);
435	} else {
436		unsigned int h2 = from_hash(nhandle >> 16);
437
438		for (fp = rtnl_dereference(b->ht[h2]);
439		     fp;
440		     fp = rtnl_dereference(fp->next))
441			if (fp->handle == f->handle)
442				return -EEXIST;
443	}
444
445	if (tb[TCA_ROUTE4_TO])
446		f->id = to;
447
448	if (tb[TCA_ROUTE4_FROM])
449		f->id = to | id<<16;
450	else if (tb[TCA_ROUTE4_IIF])
451		f->iif = id;
452
453	f->handle = nhandle;
454	f->bkt = b;
455	f->tp = tp;
456
457	if (tb[TCA_ROUTE4_CLASSID]) {
458		f->res.classid = nla_get_u32(tb[TCA_ROUTE4_CLASSID]);
459		tcf_bind_filter(tp, &f->res, base);
460	}
461
462	return 0;
463}
464
465static int route4_change(struct net *net, struct sk_buff *in_skb,
466			 struct tcf_proto *tp, unsigned long base, u32 handle,
467			 struct nlattr **tca, void **arg, bool ovr,
468			 bool rtnl_held, struct netlink_ext_ack *extack)
469{
470	struct route4_head *head = rtnl_dereference(tp->root);
471	struct route4_filter __rcu **fp;
472	struct route4_filter *fold, *f1, *pfp, *f = NULL;
473	struct route4_bucket *b;
474	struct nlattr *opt = tca[TCA_OPTIONS];
475	struct nlattr *tb[TCA_ROUTE4_MAX + 1];
476	unsigned int h, th;
477	int err;
478	bool new = true;
479
 
 
 
 
 
480	if (opt == NULL)
481		return handle ? -EINVAL : 0;
482
483	err = nla_parse_nested_deprecated(tb, TCA_ROUTE4_MAX, opt,
484					  route4_policy, NULL);
485	if (err < 0)
486		return err;
487
488	fold = *arg;
489	if (fold && handle && fold->handle != handle)
490			return -EINVAL;
491
492	err = -ENOBUFS;
493	f = kzalloc(sizeof(struct route4_filter), GFP_KERNEL);
494	if (!f)
495		goto errout;
496
497	err = tcf_exts_init(&f->exts, net, TCA_ROUTE4_ACT, TCA_ROUTE4_POLICE);
498	if (err < 0)
499		goto errout;
500
501	if (fold) {
502		f->id = fold->id;
503		f->iif = fold->iif;
504		f->res = fold->res;
505		f->handle = fold->handle;
506
507		f->tp = fold->tp;
508		f->bkt = fold->bkt;
509		new = false;
510	}
511
512	err = route4_set_parms(net, tp, base, f, handle, head, tb,
513			       tca[TCA_RATE], new, ovr, extack);
514	if (err < 0)
515		goto errout;
516
517	h = from_hash(f->handle >> 16);
518	fp = &f->bkt->ht[h];
519	for (pfp = rtnl_dereference(*fp);
520	     (f1 = rtnl_dereference(*fp)) != NULL;
521	     fp = &f1->next)
522		if (f->handle < f1->handle)
523			break;
524
525	tcf_block_netif_keep_dst(tp->chain->block);
526	rcu_assign_pointer(f->next, f1);
527	rcu_assign_pointer(*fp, f);
528
529	if (fold && fold->handle && f->handle != fold->handle) {
530		th = to_hash(fold->handle);
531		h = from_hash(fold->handle >> 16);
532		b = rtnl_dereference(head->table[th]);
533		if (b) {
534			fp = &b->ht[h];
535			for (pfp = rtnl_dereference(*fp); pfp;
536			     fp = &pfp->next, pfp = rtnl_dereference(*fp)) {
537				if (pfp == f) {
538					*fp = f->next;
539					break;
540				}
541			}
542		}
543	}
544
545	route4_reset_fastmap(head);
546	*arg = f;
547	if (fold) {
548		tcf_unbind_filter(tp, &fold->res);
549		tcf_exts_get_net(&fold->exts);
550		tcf_queue_work(&fold->rwork, route4_delete_filter_work);
551	}
552	return 0;
553
554errout:
555	if (f)
556		tcf_exts_destroy(&f->exts);
557	kfree(f);
558	return err;
559}
560
561static void route4_walk(struct tcf_proto *tp, struct tcf_walker *arg,
562			bool rtnl_held)
563{
564	struct route4_head *head = rtnl_dereference(tp->root);
565	unsigned int h, h1;
566
567	if (head == NULL || arg->stop)
568		return;
569
570	for (h = 0; h <= 256; h++) {
571		struct route4_bucket *b = rtnl_dereference(head->table[h]);
572
573		if (b) {
574			for (h1 = 0; h1 <= 32; h1++) {
575				struct route4_filter *f;
576
577				for (f = rtnl_dereference(b->ht[h1]);
578				     f;
579				     f = rtnl_dereference(f->next)) {
580					if (arg->count < arg->skip) {
581						arg->count++;
582						continue;
583					}
584					if (arg->fn(tp, f, arg) < 0) {
585						arg->stop = 1;
586						return;
587					}
588					arg->count++;
589				}
590			}
591		}
592	}
593}
594
595static int route4_dump(struct net *net, struct tcf_proto *tp, void *fh,
596		       struct sk_buff *skb, struct tcmsg *t, bool rtnl_held)
597{
598	struct route4_filter *f = fh;
599	struct nlattr *nest;
600	u32 id;
601
602	if (f == NULL)
603		return skb->len;
604
605	t->tcm_handle = f->handle;
606
607	nest = nla_nest_start_noflag(skb, TCA_OPTIONS);
608	if (nest == NULL)
609		goto nla_put_failure;
610
611	if (!(f->handle & 0x8000)) {
612		id = f->id & 0xFF;
613		if (nla_put_u32(skb, TCA_ROUTE4_TO, id))
614			goto nla_put_failure;
615	}
616	if (f->handle & 0x80000000) {
617		if ((f->handle >> 16) != 0xFFFF &&
618		    nla_put_u32(skb, TCA_ROUTE4_IIF, f->iif))
619			goto nla_put_failure;
620	} else {
621		id = f->id >> 16;
622		if (nla_put_u32(skb, TCA_ROUTE4_FROM, id))
623			goto nla_put_failure;
624	}
625	if (f->res.classid &&
626	    nla_put_u32(skb, TCA_ROUTE4_CLASSID, f->res.classid))
627		goto nla_put_failure;
628
629	if (tcf_exts_dump(skb, &f->exts) < 0)
630		goto nla_put_failure;
631
632	nla_nest_end(skb, nest);
633
634	if (tcf_exts_dump_stats(skb, &f->exts) < 0)
635		goto nla_put_failure;
636
637	return skb->len;
638
639nla_put_failure:
640	nla_nest_cancel(skb, nest);
641	return -1;
642}
643
644static void route4_bind_class(void *fh, u32 classid, unsigned long cl)
 
645{
646	struct route4_filter *f = fh;
647
648	if (f && f->res.classid == classid)
649		f->res.class = cl;
650}
651
652static struct tcf_proto_ops cls_route4_ops __read_mostly = {
653	.kind		=	"route",
654	.classify	=	route4_classify,
655	.init		=	route4_init,
656	.destroy	=	route4_destroy,
657	.get		=	route4_get,
658	.change		=	route4_change,
659	.delete		=	route4_delete,
660	.walk		=	route4_walk,
661	.dump		=	route4_dump,
662	.bind_class	=	route4_bind_class,
663	.owner		=	THIS_MODULE,
664};
665
666static int __init init_route4(void)
667{
668	return register_tcf_proto_ops(&cls_route4_ops);
669}
670
671static void __exit exit_route4(void)
672{
673	unregister_tcf_proto_ops(&cls_route4_ops);
674}
675
676module_init(init_route4)
677module_exit(exit_route4)
678MODULE_LICENSE("GPL");
v6.2
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * net/sched/cls_route.c	ROUTE4 classifier.
  4 *
  5 * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
  6 */
  7
  8#include <linux/module.h>
  9#include <linux/slab.h>
 10#include <linux/types.h>
 11#include <linux/kernel.h>
 12#include <linux/string.h>
 13#include <linux/errno.h>
 14#include <linux/skbuff.h>
 15#include <net/dst.h>
 16#include <net/route.h>
 17#include <net/netlink.h>
 18#include <net/act_api.h>
 19#include <net/pkt_cls.h>
 20#include <net/tc_wrapper.h>
 21
 22/*
 23 * 1. For now we assume that route tags < 256.
 24 *    It allows to use direct table lookups, instead of hash tables.
 25 * 2. For now we assume that "from TAG" and "fromdev DEV" statements
 26 *    are mutually  exclusive.
 27 * 3. "to TAG from ANY" has higher priority, than "to ANY from XXX"
 28 */
 29struct route4_fastmap {
 30	struct route4_filter		*filter;
 31	u32				id;
 32	int				iif;
 33};
 34
 35struct route4_head {
 36	struct route4_fastmap		fastmap[16];
 37	struct route4_bucket __rcu	*table[256 + 1];
 38	struct rcu_head			rcu;
 39};
 40
 41struct route4_bucket {
 42	/* 16 FROM buckets + 16 IIF buckets + 1 wildcard bucket */
 43	struct route4_filter __rcu	*ht[16 + 16 + 1];
 44	struct rcu_head			rcu;
 45};
 46
 47struct route4_filter {
 48	struct route4_filter __rcu	*next;
 49	u32			id;
 50	int			iif;
 51
 52	struct tcf_result	res;
 53	struct tcf_exts		exts;
 54	u32			handle;
 55	struct route4_bucket	*bkt;
 56	struct tcf_proto	*tp;
 57	struct rcu_work		rwork;
 58};
 59
 60#define ROUTE4_FAILURE ((struct route4_filter *)(-1L))
 61
 62static inline int route4_fastmap_hash(u32 id, int iif)
 63{
 64	return id & 0xF;
 65}
 66
 67static DEFINE_SPINLOCK(fastmap_lock);
 68static void
 69route4_reset_fastmap(struct route4_head *head)
 70{
 71	spin_lock_bh(&fastmap_lock);
 72	memset(head->fastmap, 0, sizeof(head->fastmap));
 73	spin_unlock_bh(&fastmap_lock);
 74}
 75
 76static void
 77route4_set_fastmap(struct route4_head *head, u32 id, int iif,
 78		   struct route4_filter *f)
 79{
 80	int h = route4_fastmap_hash(id, iif);
 81
 82	/* fastmap updates must look atomic to aling id, iff, filter */
 83	spin_lock_bh(&fastmap_lock);
 84	head->fastmap[h].id = id;
 85	head->fastmap[h].iif = iif;
 86	head->fastmap[h].filter = f;
 87	spin_unlock_bh(&fastmap_lock);
 88}
 89
 90static inline int route4_hash_to(u32 id)
 91{
 92	return id & 0xFF;
 93}
 94
 95static inline int route4_hash_from(u32 id)
 96{
 97	return (id >> 16) & 0xF;
 98}
 99
100static inline int route4_hash_iif(int iif)
101{
102	return 16 + ((iif >> 16) & 0xF);
103}
104
105static inline int route4_hash_wild(void)
106{
107	return 32;
108}
109
110#define ROUTE4_APPLY_RESULT()					\
111{								\
112	*res = f->res;						\
113	if (tcf_exts_has_actions(&f->exts)) {			\
114		int r = tcf_exts_exec(skb, &f->exts, res);	\
115		if (r < 0) {					\
116			dont_cache = 1;				\
117			continue;				\
118		}						\
119		return r;					\
120	} else if (!dont_cache)					\
121		route4_set_fastmap(head, id, iif, f);		\
122	return 0;						\
123}
124
125TC_INDIRECT_SCOPE int route4_classify(struct sk_buff *skb,
126				      const struct tcf_proto *tp,
127				      struct tcf_result *res)
128{
129	struct route4_head *head = rcu_dereference_bh(tp->root);
130	struct dst_entry *dst;
131	struct route4_bucket *b;
132	struct route4_filter *f;
133	u32 id, h;
134	int iif, dont_cache = 0;
135
136	dst = skb_dst(skb);
137	if (!dst)
138		goto failure;
139
140	id = dst->tclassid;
141
142	iif = inet_iif(skb);
143
144	h = route4_fastmap_hash(id, iif);
145
146	spin_lock(&fastmap_lock);
147	if (id == head->fastmap[h].id &&
148	    iif == head->fastmap[h].iif &&
149	    (f = head->fastmap[h].filter) != NULL) {
150		if (f == ROUTE4_FAILURE) {
151			spin_unlock(&fastmap_lock);
152			goto failure;
153		}
154
155		*res = f->res;
156		spin_unlock(&fastmap_lock);
157		return 0;
158	}
159	spin_unlock(&fastmap_lock);
160
161	h = route4_hash_to(id);
162
163restart:
164	b = rcu_dereference_bh(head->table[h]);
165	if (b) {
166		for (f = rcu_dereference_bh(b->ht[route4_hash_from(id)]);
167		     f;
168		     f = rcu_dereference_bh(f->next))
169			if (f->id == id)
170				ROUTE4_APPLY_RESULT();
171
172		for (f = rcu_dereference_bh(b->ht[route4_hash_iif(iif)]);
173		     f;
174		     f = rcu_dereference_bh(f->next))
175			if (f->iif == iif)
176				ROUTE4_APPLY_RESULT();
177
178		for (f = rcu_dereference_bh(b->ht[route4_hash_wild()]);
179		     f;
180		     f = rcu_dereference_bh(f->next))
181			ROUTE4_APPLY_RESULT();
182	}
183	if (h < 256) {
184		h = 256;
185		id &= ~0xFFFF;
186		goto restart;
187	}
188
189	if (!dont_cache)
190		route4_set_fastmap(head, id, iif, ROUTE4_FAILURE);
191failure:
192	return -1;
193}
194
195static inline u32 to_hash(u32 id)
196{
197	u32 h = id & 0xFF;
198
199	if (id & 0x8000)
200		h += 256;
201	return h;
202}
203
204static inline u32 from_hash(u32 id)
205{
206	id &= 0xFFFF;
207	if (id == 0xFFFF)
208		return 32;
209	if (!(id & 0x8000)) {
210		if (id > 255)
211			return 256;
212		return id & 0xF;
213	}
214	return 16 + (id & 0xF);
215}
216
217static void *route4_get(struct tcf_proto *tp, u32 handle)
218{
219	struct route4_head *head = rtnl_dereference(tp->root);
220	struct route4_bucket *b;
221	struct route4_filter *f;
222	unsigned int h1, h2;
223
224	h1 = to_hash(handle);
225	if (h1 > 256)
226		return NULL;
227
228	h2 = from_hash(handle >> 16);
229	if (h2 > 32)
230		return NULL;
231
232	b = rtnl_dereference(head->table[h1]);
233	if (b) {
234		for (f = rtnl_dereference(b->ht[h2]);
235		     f;
236		     f = rtnl_dereference(f->next))
237			if (f->handle == handle)
238				return f;
239	}
240	return NULL;
241}
242
243static int route4_init(struct tcf_proto *tp)
244{
245	struct route4_head *head;
246
247	head = kzalloc(sizeof(struct route4_head), GFP_KERNEL);
248	if (head == NULL)
249		return -ENOBUFS;
250
251	rcu_assign_pointer(tp->root, head);
252	return 0;
253}
254
255static void __route4_delete_filter(struct route4_filter *f)
256{
257	tcf_exts_destroy(&f->exts);
258	tcf_exts_put_net(&f->exts);
259	kfree(f);
260}
261
262static void route4_delete_filter_work(struct work_struct *work)
263{
264	struct route4_filter *f = container_of(to_rcu_work(work),
265					       struct route4_filter,
266					       rwork);
267	rtnl_lock();
268	__route4_delete_filter(f);
269	rtnl_unlock();
270}
271
272static void route4_queue_work(struct route4_filter *f)
273{
274	tcf_queue_work(&f->rwork, route4_delete_filter_work);
275}
276
277static void route4_destroy(struct tcf_proto *tp, bool rtnl_held,
278			   struct netlink_ext_ack *extack)
279{
280	struct route4_head *head = rtnl_dereference(tp->root);
281	int h1, h2;
282
283	if (head == NULL)
284		return;
285
286	for (h1 = 0; h1 <= 256; h1++) {
287		struct route4_bucket *b;
288
289		b = rtnl_dereference(head->table[h1]);
290		if (b) {
291			for (h2 = 0; h2 <= 32; h2++) {
292				struct route4_filter *f;
293
294				while ((f = rtnl_dereference(b->ht[h2])) != NULL) {
295					struct route4_filter *next;
296
297					next = rtnl_dereference(f->next);
298					RCU_INIT_POINTER(b->ht[h2], next);
299					tcf_unbind_filter(tp, &f->res);
300					if (tcf_exts_get_net(&f->exts))
301						route4_queue_work(f);
302					else
303						__route4_delete_filter(f);
304				}
305			}
306			RCU_INIT_POINTER(head->table[h1], NULL);
307			kfree_rcu(b, rcu);
308		}
309	}
310	kfree_rcu(head, rcu);
311}
312
313static int route4_delete(struct tcf_proto *tp, void *arg, bool *last,
314			 bool rtnl_held, struct netlink_ext_ack *extack)
315{
316	struct route4_head *head = rtnl_dereference(tp->root);
317	struct route4_filter *f = arg;
318	struct route4_filter __rcu **fp;
319	struct route4_filter *nf;
320	struct route4_bucket *b;
321	unsigned int h = 0;
322	int i, h1;
323
324	if (!head || !f)
325		return -EINVAL;
326
327	h = f->handle;
328	b = f->bkt;
329
330	fp = &b->ht[from_hash(h >> 16)];
331	for (nf = rtnl_dereference(*fp); nf;
332	     fp = &nf->next, nf = rtnl_dereference(*fp)) {
333		if (nf == f) {
334			/* unlink it */
335			RCU_INIT_POINTER(*fp, rtnl_dereference(f->next));
336
337			/* Remove any fastmap lookups that might ref filter
338			 * notice we unlink'd the filter so we can't get it
339			 * back in the fastmap.
340			 */
341			route4_reset_fastmap(head);
342
343			/* Delete it */
344			tcf_unbind_filter(tp, &f->res);
345			tcf_exts_get_net(&f->exts);
346			tcf_queue_work(&f->rwork, route4_delete_filter_work);
347
348			/* Strip RTNL protected tree */
349			for (i = 0; i <= 32; i++) {
350				struct route4_filter *rt;
351
352				rt = rtnl_dereference(b->ht[i]);
353				if (rt)
354					goto out;
355			}
356
357			/* OK, session has no flows */
358			RCU_INIT_POINTER(head->table[to_hash(h)], NULL);
359			kfree_rcu(b, rcu);
360			break;
361		}
362	}
363
364out:
365	*last = true;
366	for (h1 = 0; h1 <= 256; h1++) {
367		if (rcu_access_pointer(head->table[h1])) {
368			*last = false;
369			break;
370		}
371	}
372
373	return 0;
374}
375
376static const struct nla_policy route4_policy[TCA_ROUTE4_MAX + 1] = {
377	[TCA_ROUTE4_CLASSID]	= { .type = NLA_U32 },
378	[TCA_ROUTE4_TO]		= { .type = NLA_U32 },
379	[TCA_ROUTE4_FROM]	= { .type = NLA_U32 },
380	[TCA_ROUTE4_IIF]	= { .type = NLA_U32 },
381};
382
383static int route4_set_parms(struct net *net, struct tcf_proto *tp,
384			    unsigned long base, struct route4_filter *f,
385			    u32 handle, struct route4_head *head,
386			    struct nlattr **tb, struct nlattr *est, int new,
387			    u32 flags, struct netlink_ext_ack *extack)
388{
389	u32 id = 0, to = 0, nhandle = 0x8000;
390	struct route4_filter *fp;
391	unsigned int h1;
392	struct route4_bucket *b;
393	int err;
394
395	err = tcf_exts_validate(net, tp, tb, est, &f->exts, flags, extack);
396	if (err < 0)
397		return err;
398
399	if (tb[TCA_ROUTE4_TO]) {
400		if (new && handle & 0x8000)
401			return -EINVAL;
402		to = nla_get_u32(tb[TCA_ROUTE4_TO]);
403		if (to > 0xFF)
404			return -EINVAL;
405		nhandle = to;
406	}
407
408	if (tb[TCA_ROUTE4_FROM]) {
409		if (tb[TCA_ROUTE4_IIF])
410			return -EINVAL;
411		id = nla_get_u32(tb[TCA_ROUTE4_FROM]);
412		if (id > 0xFF)
413			return -EINVAL;
414		nhandle |= id << 16;
415	} else if (tb[TCA_ROUTE4_IIF]) {
416		id = nla_get_u32(tb[TCA_ROUTE4_IIF]);
417		if (id > 0x7FFF)
418			return -EINVAL;
419		nhandle |= (id | 0x8000) << 16;
420	} else
421		nhandle |= 0xFFFF << 16;
422
423	if (handle && new) {
424		nhandle |= handle & 0x7F00;
425		if (nhandle != handle)
426			return -EINVAL;
427	}
428
429	if (!nhandle) {
430		NL_SET_ERR_MSG(extack, "Replacing with handle of 0 is invalid");
431		return -EINVAL;
432	}
433
434	h1 = to_hash(nhandle);
435	b = rtnl_dereference(head->table[h1]);
436	if (!b) {
437		b = kzalloc(sizeof(struct route4_bucket), GFP_KERNEL);
438		if (b == NULL)
439			return -ENOBUFS;
440
441		rcu_assign_pointer(head->table[h1], b);
442	} else {
443		unsigned int h2 = from_hash(nhandle >> 16);
444
445		for (fp = rtnl_dereference(b->ht[h2]);
446		     fp;
447		     fp = rtnl_dereference(fp->next))
448			if (fp->handle == f->handle)
449				return -EEXIST;
450	}
451
452	if (tb[TCA_ROUTE4_TO])
453		f->id = to;
454
455	if (tb[TCA_ROUTE4_FROM])
456		f->id = to | id<<16;
457	else if (tb[TCA_ROUTE4_IIF])
458		f->iif = id;
459
460	f->handle = nhandle;
461	f->bkt = b;
462	f->tp = tp;
463
464	if (tb[TCA_ROUTE4_CLASSID]) {
465		f->res.classid = nla_get_u32(tb[TCA_ROUTE4_CLASSID]);
466		tcf_bind_filter(tp, &f->res, base);
467	}
468
469	return 0;
470}
471
472static int route4_change(struct net *net, struct sk_buff *in_skb,
473			 struct tcf_proto *tp, unsigned long base, u32 handle,
474			 struct nlattr **tca, void **arg, u32 flags,
475			 struct netlink_ext_ack *extack)
476{
477	struct route4_head *head = rtnl_dereference(tp->root);
478	struct route4_filter __rcu **fp;
479	struct route4_filter *fold, *f1, *pfp, *f = NULL;
480	struct route4_bucket *b;
481	struct nlattr *opt = tca[TCA_OPTIONS];
482	struct nlattr *tb[TCA_ROUTE4_MAX + 1];
483	unsigned int h, th;
484	int err;
485	bool new = true;
486
487	if (!handle) {
488		NL_SET_ERR_MSG(extack, "Creating with handle of 0 is invalid");
489		return -EINVAL;
490	}
491
492	if (opt == NULL)
493		return -EINVAL;
494
495	err = nla_parse_nested_deprecated(tb, TCA_ROUTE4_MAX, opt,
496					  route4_policy, NULL);
497	if (err < 0)
498		return err;
499
500	fold = *arg;
501	if (fold && fold->handle != handle)
502			return -EINVAL;
503
504	err = -ENOBUFS;
505	f = kzalloc(sizeof(struct route4_filter), GFP_KERNEL);
506	if (!f)
507		goto errout;
508
509	err = tcf_exts_init(&f->exts, net, TCA_ROUTE4_ACT, TCA_ROUTE4_POLICE);
510	if (err < 0)
511		goto errout;
512
513	if (fold) {
514		f->id = fold->id;
515		f->iif = fold->iif;
516		f->res = fold->res;
517		f->handle = fold->handle;
518
519		f->tp = fold->tp;
520		f->bkt = fold->bkt;
521		new = false;
522	}
523
524	err = route4_set_parms(net, tp, base, f, handle, head, tb,
525			       tca[TCA_RATE], new, flags, extack);
526	if (err < 0)
527		goto errout;
528
529	h = from_hash(f->handle >> 16);
530	fp = &f->bkt->ht[h];
531	for (pfp = rtnl_dereference(*fp);
532	     (f1 = rtnl_dereference(*fp)) != NULL;
533	     fp = &f1->next)
534		if (f->handle < f1->handle)
535			break;
536
537	tcf_block_netif_keep_dst(tp->chain->block);
538	rcu_assign_pointer(f->next, f1);
539	rcu_assign_pointer(*fp, f);
540
541	if (fold) {
542		th = to_hash(fold->handle);
543		h = from_hash(fold->handle >> 16);
544		b = rtnl_dereference(head->table[th]);
545		if (b) {
546			fp = &b->ht[h];
547			for (pfp = rtnl_dereference(*fp); pfp;
548			     fp = &pfp->next, pfp = rtnl_dereference(*fp)) {
549				if (pfp == fold) {
550					rcu_assign_pointer(*fp, fold->next);
551					break;
552				}
553			}
554		}
555	}
556
557	route4_reset_fastmap(head);
558	*arg = f;
559	if (fold) {
560		tcf_unbind_filter(tp, &fold->res);
561		tcf_exts_get_net(&fold->exts);
562		tcf_queue_work(&fold->rwork, route4_delete_filter_work);
563	}
564	return 0;
565
566errout:
567	if (f)
568		tcf_exts_destroy(&f->exts);
569	kfree(f);
570	return err;
571}
572
573static void route4_walk(struct tcf_proto *tp, struct tcf_walker *arg,
574			bool rtnl_held)
575{
576	struct route4_head *head = rtnl_dereference(tp->root);
577	unsigned int h, h1;
578
579	if (head == NULL || arg->stop)
580		return;
581
582	for (h = 0; h <= 256; h++) {
583		struct route4_bucket *b = rtnl_dereference(head->table[h]);
584
585		if (b) {
586			for (h1 = 0; h1 <= 32; h1++) {
587				struct route4_filter *f;
588
589				for (f = rtnl_dereference(b->ht[h1]);
590				     f;
591				     f = rtnl_dereference(f->next)) {
592					if (!tc_cls_stats_dump(tp, arg, f))
 
 
 
 
 
593						return;
 
 
594				}
595			}
596		}
597	}
598}
599
600static int route4_dump(struct net *net, struct tcf_proto *tp, void *fh,
601		       struct sk_buff *skb, struct tcmsg *t, bool rtnl_held)
602{
603	struct route4_filter *f = fh;
604	struct nlattr *nest;
605	u32 id;
606
607	if (f == NULL)
608		return skb->len;
609
610	t->tcm_handle = f->handle;
611
612	nest = nla_nest_start_noflag(skb, TCA_OPTIONS);
613	if (nest == NULL)
614		goto nla_put_failure;
615
616	if (!(f->handle & 0x8000)) {
617		id = f->id & 0xFF;
618		if (nla_put_u32(skb, TCA_ROUTE4_TO, id))
619			goto nla_put_failure;
620	}
621	if (f->handle & 0x80000000) {
622		if ((f->handle >> 16) != 0xFFFF &&
623		    nla_put_u32(skb, TCA_ROUTE4_IIF, f->iif))
624			goto nla_put_failure;
625	} else {
626		id = f->id >> 16;
627		if (nla_put_u32(skb, TCA_ROUTE4_FROM, id))
628			goto nla_put_failure;
629	}
630	if (f->res.classid &&
631	    nla_put_u32(skb, TCA_ROUTE4_CLASSID, f->res.classid))
632		goto nla_put_failure;
633
634	if (tcf_exts_dump(skb, &f->exts) < 0)
635		goto nla_put_failure;
636
637	nla_nest_end(skb, nest);
638
639	if (tcf_exts_dump_stats(skb, &f->exts) < 0)
640		goto nla_put_failure;
641
642	return skb->len;
643
644nla_put_failure:
645	nla_nest_cancel(skb, nest);
646	return -1;
647}
648
649static void route4_bind_class(void *fh, u32 classid, unsigned long cl, void *q,
650			      unsigned long base)
651{
652	struct route4_filter *f = fh;
653
654	tc_cls_bind_class(classid, cl, q, &f->res, base);
 
655}
656
657static struct tcf_proto_ops cls_route4_ops __read_mostly = {
658	.kind		=	"route",
659	.classify	=	route4_classify,
660	.init		=	route4_init,
661	.destroy	=	route4_destroy,
662	.get		=	route4_get,
663	.change		=	route4_change,
664	.delete		=	route4_delete,
665	.walk		=	route4_walk,
666	.dump		=	route4_dump,
667	.bind_class	=	route4_bind_class,
668	.owner		=	THIS_MODULE,
669};
670
671static int __init init_route4(void)
672{
673	return register_tcf_proto_ops(&cls_route4_ops);
674}
675
676static void __exit exit_route4(void)
677{
678	unregister_tcf_proto_ops(&cls_route4_ops);
679}
680
681module_init(init_route4)
682module_exit(exit_route4)
683MODULE_LICENSE("GPL");