[linux-2.6-block.git] / net / sched / cls_route.c

/*
 * net/sched/cls_route.c	ROUTE4 classifier.
 *
 *		This program is free software; you can redistribute it and/or
 *		modify it under the terms of the GNU General Public License
 *		as published by the Free Software Foundation; either version
 *		2 of the License, or (at your option) any later version.
 *
 * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
 */

#include <linux/module.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/skbuff.h>
#include <net/dst.h>
#include <net/route.h>
#include <net/netlink.h>
#include <net/act_api.h>
#include <net/pkt_cls.h>

/*
 * 1. For now we assume that route tags < 256.
 *    It allows to use direct table lookups, instead of hash tables.
 * 2. For now we assume that "from TAG" and "fromdev DEV" statements
 *    are mutually  exclusive.
 * 3. "to TAG from ANY" has higher priority, than "to ANY from XXX"
 */
struct route4_fastmap {
	struct route4_filter		*filter;
	u32				id;
	int				iif;
};

struct route4_head {
	struct route4_fastmap		fastmap[16];
	struct route4_bucket __rcu	*table[256 + 1];
	struct rcu_head			rcu;
};

struct route4_bucket {
	/* 16 FROM buckets + 16 IIF buckets + 1 wildcard bucket */
	struct route4_filter __rcu	*ht[16 + 16 + 1];
	struct rcu_head			rcu;
};

struct route4_filter {
	struct route4_filter __rcu	*next;
	u32			id;
	int			iif;

	struct tcf_result	res;
	struct tcf_exts		exts;
	u32			handle;
	struct route4_bucket	*bkt;
	struct tcf_proto	*tp;
	struct rcu_work		rwork;
};

#define ROUTE4_FAILURE ((struct route4_filter *)(-1L))

static inline int route4_fastmap_hash(u32 id, int iif)
{
	return id & 0xF;
}

static DEFINE_SPINLOCK(fastmap_lock);
static void
route4_reset_fastmap(struct route4_head *head)
{
	spin_lock_bh(&fastmap_lock);
	memset(head->fastmap, 0, sizeof(head->fastmap));
	spin_unlock_bh(&fastmap_lock);
}

static void
route4_set_fastmap(struct route4_head *head, u32 id, int iif,
		   struct route4_filter *f)
{
	int h = route4_fastmap_hash(id, iif);

	/* fastmap updates must look atomic to aling id, iff, filter */
	spin_lock_bh(&fastmap_lock);
	head->fastmap[h].id = id;
	head->fastmap[h].iif = iif;
	head->fastmap[h].filter = f;
	spin_unlock_bh(&fastmap_lock);
}

static inline int route4_hash_to(u32 id)
{
	return id & 0xFF;
}

static inline int route4_hash_from(u32 id)
{
	return (id >> 16) & 0xF;
}

static inline int route4_hash_iif(int iif)
{
	return 16 + ((iif >> 16) & 0xF);
}

static inline int route4_hash_wild(void)
{
	return 32;
}

#define ROUTE4_APPLY_RESULT()					\
{								\
	*res = f->res;						\
	if (tcf_exts_has_actions(&f->exts)) {			\
		int r = tcf_exts_exec(skb, &f->exts, res);	\
		if (r < 0) {					\
			dont_cache = 1;				\
			continue;				\
		}						\
		return r;					\
	} else if (!dont_cache)					\
		route4_set_fastmap(head, id, iif, f);		\
	return 0;						\
}

static int route4_classify(struct sk_buff *skb, const struct tcf_proto *tp,
			   struct tcf_result *res)
{
	struct route4_head *head = rcu_dereference_bh(tp->root);
	struct dst_entry *dst;
	struct route4_bucket *b;
	struct route4_filter *f;
	u32 id, h;
	int iif, dont_cache = 0;

	dst = skb_dst(skb);
	if (!dst)
		goto failure;

	id = dst->tclassid;

	iif = inet_iif(skb);

	h = route4_fastmap_hash(id, iif);

	spin_lock(&fastmap_lock);
	if (id == head->fastmap[h].id &&
	    iif == head->fastmap[h].iif &&
	    (f = head->fastmap[h].filter) != NULL) {
		if (f == ROUTE4_FAILURE) {
			spin_unlock(&fastmap_lock);
			goto failure;
		}

		*res = f->res;
		spin_unlock(&fastmap_lock);
		return 0;
	}
	spin_unlock(&fastmap_lock);

	h = route4_hash_to(id);

restart:
	b = rcu_dereference_bh(head->table[h]);
	if (b) {
		for (f = rcu_dereference_bh(b->ht[route4_hash_from(id)]);
		     f;
		     f = rcu_dereference_bh(f->next))
			if (f->id == id)
				ROUTE4_APPLY_RESULT();

		for (f = rcu_dereference_bh(b->ht[route4_hash_iif(iif)]);
		     f;
		     f = rcu_dereference_bh(f->next))
			if (f->iif == iif)
				ROUTE4_APPLY_RESULT();

		for (f = rcu_dereference_bh(b->ht[route4_hash_wild()]);
		     f;
		     f = rcu_dereference_bh(f->next))
			ROUTE4_APPLY_RESULT();
	}
	if (h < 256) {
		h = 256;
		id &= ~0xFFFF;
		goto restart;
	}

	if (!dont_cache)
		route4_set_fastmap(head, id, iif, ROUTE4_FAILURE);
failure:
	return -1;
}

static inline u32 to_hash(u32 id)
{
	u32 h = id & 0xFF;

	if (id & 0x8000)
		h += 256;
	return h;
}

static inline u32 from_hash(u32 id)
{
	id &= 0xFFFF;
	if (id == 0xFFFF)
		return 32;
	if (!(id & 0x8000)) {
		if (id > 255)
			return 256;
		return id & 0xF;
	}
	return 16 + (id & 0xF);
}

static void *route4_get(struct tcf_proto *tp, u32 handle)
{
	struct route4_head *head = rtnl_dereference(tp->root);
	struct route4_bucket *b;
	struct route4_filter *f;
	unsigned int h1, h2;

	h1 = to_hash(handle);
	if (h1 > 256)
		return NULL;

	h2 = from_hash(handle >> 16);
	if (h2 > 32)
		return NULL;

	b = rtnl_dereference(head->table[h1]);
	if (b) {
		for (f = rtnl_dereference(b->ht[h2]);
		     f;
		     f = rtnl_dereference(f->next))
			if (f->handle == handle)
				return f;
	}
	return NULL;
}

static int route4_init(struct tcf_proto *tp)
{
	struct route4_head *head;

	head = kzalloc(sizeof(struct route4_head), GFP_KERNEL);
	if (head == NULL)
		return -ENOBUFS;

	rcu_assign_pointer(tp->root, head);
	return 0;
}

static void __route4_delete_filter(struct route4_filter *f)
{
	tcf_exts_destroy(&f->exts);
	tcf_exts_put_net(&f->exts);
	kfree(f);
}

static void route4_delete_filter_work(struct work_struct *work)
{
	struct route4_filter *f = container_of(to_rcu_work(work),
					       struct route4_filter,
					       rwork);
	rtnl_lock();
	__route4_delete_filter(f);
	rtnl_unlock();
}

static void route4_queue_work(struct route4_filter *f)
{
	tcf_queue_work(&f->rwork, route4_delete_filter_work);
}

static void route4_destroy(struct tcf_proto *tp, struct netlink_ext_ack *extack)
{
	struct route4_head *head = rtnl_dereference(tp->root);
	int h1, h2;

	if (head == NULL)
		return;

	for (h1 = 0; h1 <= 256; h1++) {
		struct route4_bucket *b;

		b = rtnl_dereference(head->table[h1]);
		if (b) {
			for (h2 = 0; h2 <= 32; h2++) {
				struct route4_filter *f;

				while ((f = rtnl_dereference(b->ht[h2])) != NULL) {
					struct route4_filter *next;

					next = rtnl_dereference(f->next);
					RCU_INIT_POINTER(b->ht[h2], next);
					tcf_unbind_filter(tp, &f->res);
					if (tcf_exts_get_net(&f->exts))
						route4_queue_work(f);
					else
						__route4_delete_filter(f);
				}
			}
			RCU_INIT_POINTER(head->table[h1], NULL);
			kfree_rcu(b, rcu);
		}
	}
	kfree_rcu(head, rcu);
}

static int route4_delete(struct tcf_proto *tp, void *arg, bool *last,
			 struct netlink_ext_ack *extack)
{
	struct route4_head *head = rtnl_dereference(tp->root);
	struct route4_filter *f = arg;
	struct route4_filter __rcu **fp;
	struct route4_filter *nf;
	struct route4_bucket *b;
	unsigned int h = 0;
	int i, h1;

	if (!head || !f)
		return -EINVAL;

	h = f->handle;
	b = f->bkt;

	fp = &b->ht[from_hash(h >> 16)];
	for (nf = rtnl_dereference(*fp); nf;
	     fp = &nf->next, nf = rtnl_dereference(*fp)) {
		if (nf == f) {
			/* unlink it */
			RCU_INIT_POINTER(*fp, rtnl_dereference(f->next));

			/* Remove any fastmap lookups that might ref filter
			 * notice we unlink'd the filter so we can't get it
			 * back in the fastmap.
			 */
			route4_reset_fastmap(head);

			/* Delete it */
			tcf_unbind_filter(tp, &f->res);
			tcf_exts_get_net(&f->exts);
			tcf_queue_work(&f->rwork, route4_delete_filter_work);

			/* Strip RTNL protected tree */
			for (i = 0; i <= 32; i++) {
				struct route4_filter *rt;

				rt = rtnl_dereference(b->ht[i]);
				if (rt)
					goto out;
			}

			/* OK, session has no flows */
			RCU_INIT_POINTER(head->table[to_hash(h)], NULL);
			kfree_rcu(b, rcu);
			break;
		}
	}

out:
	*last = true;
	for (h1 = 0; h1 <= 256; h1++) {
		if (rcu_access_pointer(head->table[h1])) {
			*last = false;
			break;
		}
	}

	return 0;
}

static const struct nla_policy route4_policy[TCA_ROUTE4_MAX + 1] = {
	[TCA_ROUTE4_CLASSID]	= { .type = NLA_U32 },
	[TCA_ROUTE4_TO]		= { .type = NLA_U32 },
	[TCA_ROUTE4_FROM]	= { .type = NLA_U32 },
	[TCA_ROUTE4_IIF]	= { .type = NLA_U32 },
};

static int route4_set_parms(struct net *net, struct tcf_proto *tp,
			    unsigned long base, struct route4_filter *f,
			    u32 handle, struct route4_head *head,
			    struct nlattr **tb, struct nlattr *est, int new,
			    bool ovr, struct netlink_ext_ack *extack)
{
	u32 id = 0, to = 0, nhandle = 0x8000;
	struct route4_filter *fp;
	unsigned int h1;
	struct route4_bucket *b;
	int err;

	err = tcf_exts_validate(net, tp, tb, est, &f->exts, ovr, extack);
	if (err < 0)
		return err;

	if (tb[TCA_ROUTE4_TO]) {
		if (new && handle & 0x8000)
			return -EINVAL;
		to = nla_get_u32(tb[TCA_ROUTE4_TO]);
		if (to > 0xFF)
			return -EINVAL;
		nhandle = to;
	}

	if (tb[TCA_ROUTE4_FROM]) {
		if (tb[TCA_ROUTE4_IIF])
			return -EINVAL;
		id = nla_get_u32(tb[TCA_ROUTE4_FROM]);
		if (id > 0xFF)
			return -EINVAL;
		nhandle |= id << 16;
	} else if (tb[TCA_ROUTE4_IIF]) {
		id = nla_get_u32(tb[TCA_ROUTE4_IIF]);
		if (id > 0x7FFF)
			return -EINVAL;
		nhandle |= (id | 0x8000) << 16;
	} else
		nhandle |= 0xFFFF << 16;

	if (handle && new) {
		nhandle |= handle & 0x7F00;
		if (nhandle != handle)
			return -EINVAL;
	}

	h1 = to_hash(nhandle);
	b = rtnl_dereference(head->table[h1]);
	if (!b) {
		b = kzalloc(sizeof(struct route4_bucket), GFP_KERNEL);
		if (b == NULL)
			return -ENOBUFS;

		rcu_assign_pointer(head->table[h1], b);
	} else {
		unsigned int h2 = from_hash(nhandle >> 16);

		for (fp = rtnl_dereference(b->ht[h2]);
		     fp;
		     fp = rtnl_dereference(fp->next))
			if (fp->handle == f->handle)
				return -EEXIST;
	}

	if (tb[TCA_ROUTE4_TO])
		f->id = to;

	if (tb[TCA_ROUTE4_FROM])
		f->id = to | id<<16;
	else if (tb[TCA_ROUTE4_IIF])
		f->iif = id;

	f->handle = nhandle;
	f->bkt = b;
	f->tp = tp;

	if (tb[TCA_ROUTE4_CLASSID]) {
		f->res.classid = nla_get_u32(tb[TCA_ROUTE4_CLASSID]);
		tcf_bind_filter(tp, &f->res, base);
	}

	return 0;
}

static int route4_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,
			 struct netlink_ext_ack *extack)
{
	struct route4_head *head = rtnl_dereference(tp->root);
	struct route4_filter __rcu **fp;
	struct route4_filter *fold, *f1, *pfp, *f = NULL;
	struct route4_bucket *b;
	struct nlattr *opt = tca[TCA_OPTIONS];
	struct nlattr *tb[TCA_ROUTE4_MAX + 1];
	unsigned int h, th;
	int err;
	bool new = true;

	if (opt == NULL)
		return handle ? -EINVAL : 0;

	err = nla_parse_nested(tb, TCA_ROUTE4_MAX, opt, route4_policy, NULL);
	if (err < 0)
		return err;

	fold = *arg;
	if (fold && handle && fold->handle != handle)
			return -EINVAL;

	err = -ENOBUFS;
	f = kzalloc(sizeof(struct route4_filter), GFP_KERNEL);
	if (!f)
		goto errout;

	err = tcf_exts_init(&f->exts, TCA_ROUTE4_ACT, TCA_ROUTE4_POLICE);
	if (err < 0)
		goto errout;

	if (fold) {
		f->id = fold->id;
		f->iif = fold->iif;
		f->res = fold->res;
		f->handle = fold->handle;

		f->tp = fold->tp;
		f->bkt = fold->bkt;
		new = false;
	}

	err = route4_set_parms(net, tp, base, f, handle, head, tb,
			       tca[TCA_RATE], new, ovr, extack);
	if (err < 0)
		goto errout;

	h = from_hash(f->handle >> 16);
	fp = &f->bkt->ht[h];
	for (pfp = rtnl_dereference(*fp);
	     (f1 = rtnl_dereference(*fp)) != NULL;
	     fp = &f1->next)
		if (f->handle < f1->handle)
			break;

	tcf_block_netif_keep_dst(tp->chain->block);
	rcu_assign_pointer(f->next, f1);
	rcu_assign_pointer(*fp, f);

	if (fold && fold->handle && f->handle != fold->handle) {
		th = to_hash(fold->handle);
		h = from_hash(fold->handle >> 16);
		b = rtnl_dereference(head->table[th]);
		if (b) {
			fp = &b->ht[h];
			for (pfp = rtnl_dereference(*fp); pfp;
			     fp = &pfp->next, pfp = rtnl_dereference(*fp)) {
				if (pfp == f) {
					*fp = f->next;
					break;
				}
			}
		}
	}

	route4_reset_fastmap(head);
	*arg = f;
	if (fold) {
		tcf_unbind_filter(tp, &fold->res);
		tcf_exts_get_net(&fold->exts);
		tcf_queue_work(&fold->rwork, route4_delete_filter_work);
	}
	return 0;

errout:
	if (f)
		tcf_exts_destroy(&f->exts);
	kfree(f);
	return err;
}

static void route4_walk(struct tcf_proto *tp, struct tcf_walker *arg)
{
	struct route4_head *head = rtnl_dereference(tp->root);
	unsigned int h, h1;

	if (head == NULL)
		arg->stop = 1;

	if (arg->stop)
		return;

	for (h = 0; h <= 256; h++) {
		struct route4_bucket *b = rtnl_dereference(head->table[h]);

		if (b) {
			for (h1 = 0; h1 <= 32; h1++) {
				struct route4_filter *f;

				for (f = rtnl_dereference(b->ht[h1]);
				     f;
				     f = rtnl_dereference(f->next)) {
					if (arg->count < arg->skip) {
						arg->count++;
						continue;
					}
					if (arg->fn(tp, f, arg) < 0) {
						arg->stop = 1;
						return;
					}
					arg->count++;
				}
			}
		}
	}
}

static int route4_dump(struct net *net, struct tcf_proto *tp, void *fh,
		       struct sk_buff *skb, struct tcmsg *t)
{
	struct route4_filter *f = fh;
	struct nlattr *nest;
	u32 id;

	if (f == NULL)
		return skb->len;

	t->tcm_handle = f->handle;

	nest = nla_nest_start(skb, TCA_OPTIONS);
	if (nest == NULL)
		goto nla_put_failure;

	if (!(f->handle & 0x8000)) {
		id = f->id & 0xFF;
		if (nla_put_u32(skb, TCA_ROUTE4_TO, id))
			goto nla_put_failure;
	}
	if (f->handle & 0x80000000) {
		if ((f->handle >> 16) != 0xFFFF &&
		    nla_put_u32(skb, TCA_ROUTE4_IIF, f->iif))
			goto nla_put_failure;
	} else {
		id = f->id >> 16;
		if (nla_put_u32(skb, TCA_ROUTE4_FROM, id))
			goto nla_put_failure;
	}
	if (f->res.classid &&
	    nla_put_u32(skb, TCA_ROUTE4_CLASSID, f->res.classid))
		goto nla_put_failure;

	if (tcf_exts_dump(skb, &f->exts) < 0)
		goto nla_put_failure;

	nla_nest_end(skb, nest);

	if (tcf_exts_dump_stats(skb, &f->exts) < 0)
		goto nla_put_failure;

	return skb->len;

nla_put_failure:
	nla_nest_cancel(skb, nest);
	return -1;
}

static void route4_bind_class(void *fh, u32 classid, unsigned long cl)
{
	struct route4_filter *f = fh;

	if (f && f->res.classid == classid)
		f->res.class = cl;
}

static struct tcf_proto_ops cls_route4_ops __read_mostly = {
	.kind		=	"route",
	.classify	=	route4_classify,
	.init		=	route4_init,
	.destroy	=	route4_destroy,
	.get		=	route4_get,
	.change		=	route4_change,
	.delete		=	route4_delete,
	.walk		=	route4_walk,
	.dump		=	route4_dump,
	.bind_class	=	route4_bind_class,
	.owner		=	THIS_MODULE,
};

static int __init init_route4(void)
{
	return register_tcf_proto_ops(&cls_route4_ops);
}

static void __exit exit_route4(void)
{
	unregister_tcf_proto_ops(&cls_route4_ops);
}

module_init(init_route4)
module_exit(exit_route4)
MODULE_LICENSE("GPL");
Commit	Line	Data
1da177e4 LT	1	/*
	2	* net/sched/cls_route.c ROUTE4 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
	12	#include <linux/module.h>
5a0e3ad6	13	#include <linux/slab.h>
1da177e4 LT	14	#include <linux/types.h>
1da177e4 LT	15	#include <linux/kernel.h>
1da177e4	16	#include <linux/string.h>
1da177e4	17	#include <linux/errno.h>
1da177e4	18	#include <linux/skbuff.h>
0ba48053 PM	19	#include <net/dst.h>
	20	#include <net/route.h>
	21	#include <net/netlink.h>
1da177e4 LT	22	#include <net/act_api.h>
	23	#include <net/pkt_cls.h>
	24
	25	/*
cc7ec456 ED	26	* 1. For now we assume that route tags < 256.
	27	* It allows to use direct table lookups, instead of hash tables.
	28	* 2. For now we assume that "from TAG" and "fromdev DEV" statements
	29	* are mutually exclusive.
	30	* 3. "to TAG from ANY" has higher priority, than "to ANY from XXX"
1da177e4	31	*/
cc7ec456	32	struct route4_fastmap {
1109c005 JF	33	struct route4_filter *filter;
	34	u32 id;
	35	int iif;
1da177e4 LT	36	};
1da177e4 LT	37
cc7ec456	38	struct route4_head {
1109c005 JF	39	struct route4_fastmap fastmap[16];
	40	struct route4_bucket __rcu *table[256 + 1];
	41	struct rcu_head rcu;
1da177e4 LT	42	};
1da177e4 LT	43
cc7ec456	44	struct route4_bucket {
1da177e4	45	/* 16 FROM buckets + 16 IIF buckets + 1 wildcard bucket */
1109c005 JF	46	struct route4_filter __rcu *ht[16 + 16 + 1];
1109c005 JF	47	struct rcu_head rcu;
1da177e4 LT	48	};
1da177e4 LT	49
cc7ec456	50	struct route4_filter {
1109c005	51	struct route4_filter __rcu *next;
1da177e4 LT	52	u32 id;
	53	int iif;
	54
	55	struct tcf_result res;
	56	struct tcf_exts exts;
	57	u32 handle;
	58	struct route4_bucket *bkt;
1109c005	59	struct tcf_proto *tp;
aaa908ff	60	struct rcu_work rwork;
1da177e4 LT	61	};
1da177e4 LT	62
cc7ec456	63	#define ROUTE4_FAILURE ((struct route4_filter *)(-1L))
1da177e4	64
cc7ec456	65	static inline int route4_fastmap_hash(u32 id, int iif)
1da177e4	66	{
cc7ec456	67	return id & 0xF;
1da177e4 LT	68	}
1da177e4 LT	69
1109c005	70	static DEFINE_SPINLOCK(fastmap_lock);
cc7ec456	71	static void
1109c005	72	route4_reset_fastmap(struct route4_head *head)
1da177e4	73	{
1109c005	74	spin_lock_bh(&fastmap_lock);
1da177e4	75	memset(head->fastmap, 0, sizeof(head->fastmap));
1109c005	76	spin_unlock_bh(&fastmap_lock);
1da177e4 LT	77	}
1da177e4 LT	78
cc7ec456	79	static void
1da177e4 LT	80	route4_set_fastmap(struct route4_head *head, u32 id, int iif,
	81	struct route4_filter *f)
	82	{
	83	int h = route4_fastmap_hash(id, iif);
cc7ec456	84
1109c005 JF	85	/* fastmap updates must look atomic to aling id, iff, filter */
1109c005 JF	86	spin_lock_bh(&fastmap_lock);
1da177e4 LT	87	head->fastmap[h].id = id;
	88	head->fastmap[h].iif = iif;
	89	head->fastmap[h].filter = f;
1109c005	90	spin_unlock_bh(&fastmap_lock);
1da177e4 LT	91	}
1da177e4 LT	92
cc7ec456	93	static inline int route4_hash_to(u32 id)
1da177e4	94	{
cc7ec456	95	return id & 0xFF;
1da177e4 LT	96	}
1da177e4 LT	97
cc7ec456	98	static inline int route4_hash_from(u32 id)
1da177e4	99	{
cc7ec456	100	return (id >> 16) & 0xF;
1da177e4 LT	101	}
1da177e4 LT	102
cc7ec456	103	static inline int route4_hash_iif(int iif)
1da177e4	104	{
cc7ec456	105	return 16 + ((iif >> 16) & 0xF);
1da177e4 LT	106	}
1da177e4 LT	107
cc7ec456	108	static inline int route4_hash_wild(void)
1da177e4 LT	109	{
	110	return 32;
	111	}
	112
	113	#define ROUTE4_APPLY_RESULT() \
	114	{ \
	115	*res = f->res; \
6fc6d06e	116	if (tcf_exts_has_actions(&f->exts)) { \
1da177e4 LT	117	int r = tcf_exts_exec(skb, &f->exts, res); \
	118	if (r < 0) { \
	119	dont_cache = 1; \
	120	continue; \
	121	} \
	122	return r; \
	123	} else if (!dont_cache) \
	124	route4_set_fastmap(head, id, iif, f); \
	125	return 0; \
	126	}
	127
dc7f9f6e	128	static int route4_classify(struct sk_buff skb, const struct tcf_proto tp,
1da177e4 LT	129	struct tcf_result *res)
1da177e4 LT	130	{
1109c005	131	struct route4_head *head = rcu_dereference_bh(tp->root);
1da177e4 LT	132	struct dst_entry *dst;
	133	struct route4_bucket *b;
	134	struct route4_filter *f;
	135	u32 id, h;
	136	int iif, dont_cache = 0;
	137
cc7ec456 ED	138	dst = skb_dst(skb);
cc7ec456 ED	139	if (!dst)
1da177e4 LT	140	goto failure;
	141
	142	id = dst->tclassid;
1da177e4	143
92101b3b	144	iif = inet_iif(skb);
1da177e4 LT	145
1da177e4 LT	146	h = route4_fastmap_hash(id, iif);
1109c005 JF	147
1109c005 JF	148	spin_lock(&fastmap_lock);
1da177e4 LT	149	if (id == head->fastmap[h].id &&
	150	iif == head->fastmap[h].iif &&
	151	(f = head->fastmap[h].filter) != NULL) {
1109c005 JF	152	if (f == ROUTE4_FAILURE) {
1109c005 JF	153	spin_unlock(&fastmap_lock);
1da177e4	154	goto failure;
1109c005	155	}
1da177e4 LT	156
1da177e4 LT	157	*res = f->res;
1109c005	158	spin_unlock(&fastmap_lock);
1da177e4 LT	159	return 0;
1da177e4 LT	160	}
1109c005	161	spin_unlock(&fastmap_lock);
1da177e4 LT	162
	163	h = route4_hash_to(id);
	164
	165	restart:
1109c005	166	b = rcu_dereference_bh(head->table[h]);
cc7ec456	167	if (b) {
1109c005 JF	168	for (f = rcu_dereference_bh(b->ht[route4_hash_from(id)]);
	169	f;
	170	f = rcu_dereference_bh(f->next))
1da177e4 LT	171	if (f->id == id)
	172	ROUTE4_APPLY_RESULT();
	173
1109c005 JF	174	for (f = rcu_dereference_bh(b->ht[route4_hash_iif(iif)]);
	175	f;
	176	f = rcu_dereference_bh(f->next))
1da177e4 LT	177	if (f->iif == iif)
	178	ROUTE4_APPLY_RESULT();
	179
1109c005 JF	180	for (f = rcu_dereference_bh(b->ht[route4_hash_wild()]);
	181	f;
	182	f = rcu_dereference_bh(f->next))
1da177e4	183	ROUTE4_APPLY_RESULT();
1da177e4 LT	184	}
	185	if (h < 256) {
	186	h = 256;
	187	id &= ~0xFFFF;
	188	goto restart;
	189	}
	190
	191	if (!dont_cache)
	192	route4_set_fastmap(head, id, iif, ROUTE4_FAILURE);
	193	failure:
	194	return -1;
1da177e4 LT	195	}
	196
	197	static inline u32 to_hash(u32 id)
	198	{
cc7ec456 ED	199	u32 h = id & 0xFF;
	200
	201	if (id & 0x8000)
1da177e4 LT	202	h += 256;
	203	return h;
	204	}
	205
	206	static inline u32 from_hash(u32 id)
	207	{
	208	id &= 0xFFFF;
	209	if (id == 0xFFFF)
	210	return 32;
	211	if (!(id & 0x8000)) {
	212	if (id > 255)
	213	return 256;
cc7ec456	214	return id & 0xF;
1da177e4	215	}
cc7ec456	216	return 16 + (id & 0xF);
1da177e4 LT	217	}
1da177e4 LT	218
8113c095	219	static void route4_get(struct tcf_proto tp, u32 handle)
1da177e4	220	{
1109c005	221	struct route4_head *head = rtnl_dereference(tp->root);
1da177e4 LT	222	struct route4_bucket *b;
1da177e4 LT	223	struct route4_filter *f;
cc7ec456	224	unsigned int h1, h2;
1da177e4	225
1da177e4 LT	226	h1 = to_hash(handle);
1da177e4 LT	227	if (h1 > 256)
8113c095	228	return NULL;
1da177e4	229
cc7ec456	230	h2 = from_hash(handle >> 16);
1da177e4	231	if (h2 > 32)
8113c095	232	return NULL;
1da177e4	233
1109c005	234	b = rtnl_dereference(head->table[h1]);
cc7ec456	235	if (b) {
1109c005 JF	236	for (f = rtnl_dereference(b->ht[h2]);
	237	f;
	238	f = rtnl_dereference(f->next))
1da177e4	239	if (f->handle == handle)
8113c095	240	return f;
1da177e4	241	}
8113c095	242	return NULL;
1da177e4 LT	243	}
1da177e4 LT	244
1da177e4 LT	245	static int route4_init(struct tcf_proto *tp)
1da177e4 LT	246	{
a05c2d11 WC	247	struct route4_head *head;
	248
	249	head = kzalloc(sizeof(struct route4_head), GFP_KERNEL);
	250	if (head == NULL)
	251	return -ENOBUFS;
	252
	253	rcu_assign_pointer(tp->root, head);
1da177e4 LT	254	return 0;
	255	}
	256
3fd51de5 CW	257	static void __route4_delete_filter(struct route4_filter *f)
	258	{
	259	tcf_exts_destroy(&f->exts);
	260	tcf_exts_put_net(&f->exts);
	261	kfree(f);
	262	}
	263
c2f3f31d	264	static void route4_delete_filter_work(struct work_struct *work)
1da177e4	265	{
aaa908ff CW	266	struct route4_filter *f = container_of(to_rcu_work(work),
	267	struct route4_filter,
	268	rwork);
c2f3f31d	269	rtnl_lock();
3fd51de5	270	__route4_delete_filter(f);
c2f3f31d CW	271	rtnl_unlock();
	272	}
	273
aaa908ff	274	static void route4_queue_work(struct route4_filter *f)
c2f3f31d	275	{
aaa908ff	276	tcf_queue_work(&f->rwork, route4_delete_filter_work);
1da177e4 LT	277	}
1da177e4 LT	278
715df5ec	279	static void route4_destroy(struct tcf_proto tp, struct netlink_ext_ack extack)
1da177e4	280	{
1109c005	281	struct route4_head *head = rtnl_dereference(tp->root);
1da177e4 LT	282	int h1, h2;
	283
	284	if (head == NULL)
763dbf63	285	return;
1da177e4	286
cc7ec456	287	for (h1 = 0; h1 <= 256; h1++) {
1da177e4 LT	288	struct route4_bucket *b;
1da177e4 LT	289
1109c005	290	b = rtnl_dereference(head->table[h1]);
cc7ec456 ED	291	if (b) {
cc7ec456 ED	292	for (h2 = 0; h2 <= 32; h2++) {
1da177e4 LT	293	struct route4_filter *f;
1da177e4 LT	294
1109c005 JF	295	while ((f = rtnl_dereference(b->ht[h2])) != NULL) {
	296	struct route4_filter *next;
	297
	298	next = rtnl_dereference(f->next);
	299	RCU_INIT_POINTER(b->ht[h2], next);
18cdb37e	300	tcf_unbind_filter(tp, &f->res);
3fd51de5	301	if (tcf_exts_get_net(&f->exts))
aaa908ff	302	route4_queue_work(f);
3fd51de5 CW	303	else
3fd51de5 CW	304	__route4_delete_filter(f);
1da177e4 LT	305	}
1da177e4 LT	306	}
1109c005 JF	307	RCU_INIT_POINTER(head->table[h1], NULL);
1109c005 JF	308	kfree_rcu(b, rcu);
1da177e4 LT	309	}
1da177e4 LT	310	}
1109c005	311	kfree_rcu(head, rcu);
1da177e4 LT	312	}
1da177e4 LT	313
571acf21 AA	314	static int route4_delete(struct tcf_proto tp, void arg, bool *last,
571acf21 AA	315	struct netlink_ext_ack *extack)
1da177e4	316	{
1109c005	317	struct route4_head *head = rtnl_dereference(tp->root);
8113c095	318	struct route4_filter *f = arg;
1109c005 JF	319	struct route4_filter __rcu **fp;
1109c005 JF	320	struct route4_filter *nf;
1da177e4	321	struct route4_bucket *b;
1109c005	322	unsigned int h = 0;
763dbf63	323	int i, h1;
1da177e4 LT	324
	325	if (!head \|\| !f)
	326	return -EINVAL;
	327
	328	h = f->handle;
	329	b = f->bkt;
	330
1109c005 JF	331	fp = &b->ht[from_hash(h >> 16)];
	332	for (nf = rtnl_dereference(*fp); nf;
	333	fp = &nf->next, nf = rtnl_dereference(*fp)) {
	334	if (nf == f) {
	335	/* unlink it */
	336	RCU_INIT_POINTER(*fp, rtnl_dereference(f->next));
1da177e4	337
1109c005 JF	338	/* Remove any fastmap lookups that might ref filter
	339	* notice we unlink'd the filter so we can't get it
	340	* back in the fastmap.
	341	*/
	342	route4_reset_fastmap(head);
1da177e4	343
1109c005	344	/* Delete it */
18cdb37e	345	tcf_unbind_filter(tp, &f->res);
3fd51de5	346	tcf_exts_get_net(&f->exts);
aaa908ff	347	tcf_queue_work(&f->rwork, route4_delete_filter_work);
1da177e4	348
1109c005 JF	349	/* Strip RTNL protected tree */
	350	for (i = 0; i <= 32; i++) {
	351	struct route4_filter *rt;
	352
	353	rt = rtnl_dereference(b->ht[i]);
	354	if (rt)
763dbf63	355	goto out;
1109c005	356	}
1da177e4 LT	357
1da177e4 LT	358	/* OK, session has no flows */
1109c005 JF	359	RCU_INIT_POINTER(head->table[to_hash(h)], NULL);
1109c005 JF	360	kfree_rcu(b, rcu);
763dbf63 WC	361	break;
	362	}
	363	}
1da177e4	364
763dbf63 WC	365	out:
	366	*last = true;
	367	for (h1 = 0; h1 <= 256; h1++) {
	368	if (rcu_access_pointer(head->table[h1])) {
	369	*last = false;
	370	break;
1da177e4 LT	371	}
1da177e4 LT	372	}
763dbf63	373
1da177e4 LT	374	return 0;
	375	}
	376
6fa8c014 PM	377	static const struct nla_policy route4_policy[TCA_ROUTE4_MAX + 1] = {
	378	[TCA_ROUTE4_CLASSID] = { .type = NLA_U32 },
	379	[TCA_ROUTE4_TO] = { .type = NLA_U32 },
	380	[TCA_ROUTE4_FROM] = { .type = NLA_U32 },
	381	[TCA_ROUTE4_IIF] = { .type = NLA_U32 },
	382	};
	383
c1b52739 BL	384	static int route4_set_parms(struct net net, struct tcf_proto tp,
	385	unsigned long base, struct route4_filter *f,
	386	u32 handle, struct route4_head *head,
2f7ef2f8	387	struct nlattr *tb, struct nlattr est, int new,
50a56190	388	bool ovr, struct netlink_ext_ack *extack)
1da177e4	389	{
1da177e4 LT	390	u32 id = 0, to = 0, nhandle = 0x8000;
	391	struct route4_filter *fp;
	392	unsigned int h1;
	393	struct route4_bucket *b;
b9a24bb7	394	int err;
1da177e4	395
50a56190	396	err = tcf_exts_validate(net, tp, tb, est, &f->exts, ovr, extack);
1da177e4 LT	397	if (err < 0)
	398	return err;
	399
add93b61	400	if (tb[TCA_ROUTE4_TO]) {
1da177e4	401	if (new && handle & 0x8000)
8c98d571	402	return -EINVAL;
1587bac4	403	to = nla_get_u32(tb[TCA_ROUTE4_TO]);
1da177e4	404	if (to > 0xFF)
8c98d571	405	return -EINVAL;
1da177e4 LT	406	nhandle = to;
	407	}
	408
add93b61 PM	409	if (tb[TCA_ROUTE4_FROM]) {
add93b61 PM	410	if (tb[TCA_ROUTE4_IIF])
8c98d571	411	return -EINVAL;
1587bac4	412	id = nla_get_u32(tb[TCA_ROUTE4_FROM]);
1da177e4	413	if (id > 0xFF)
8c98d571	414	return -EINVAL;
1da177e4	415	nhandle \|= id << 16;
add93b61	416	} else if (tb[TCA_ROUTE4_IIF]) {
1587bac4	417	id = nla_get_u32(tb[TCA_ROUTE4_IIF]);
1da177e4	418	if (id > 0x7FFF)
8c98d571	419	return -EINVAL;
1da177e4 LT	420	nhandle \|= (id \| 0x8000) << 16;
	421	} else
	422	nhandle \|= 0xFFFF << 16;
	423
	424	if (handle && new) {
	425	nhandle \|= handle & 0x7F00;
	426	if (nhandle != handle)
8c98d571	427	return -EINVAL;
1da177e4 LT	428	}
	429
	430	h1 = to_hash(nhandle);
1109c005	431	b = rtnl_dereference(head->table[h1]);
cc7ec456	432	if (!b) {
0da974f4	433	b = kzalloc(sizeof(struct route4_bucket), GFP_KERNEL);
1da177e4	434	if (b == NULL)
8c98d571	435	return -ENOBUFS;
1da177e4	436
1109c005	437	rcu_assign_pointer(head->table[h1], b);
1da177e4 LT	438	} else {
1da177e4 LT	439	unsigned int h2 = from_hash(nhandle >> 16);
cc7ec456	440
1109c005 JF	441	for (fp = rtnl_dereference(b->ht[h2]);
	442	fp;
	443	fp = rtnl_dereference(fp->next))
1da177e4	444	if (fp->handle == f->handle)
8c98d571	445	return -EEXIST;
1da177e4 LT	446	}
1da177e4 LT	447
add93b61	448	if (tb[TCA_ROUTE4_TO])
1da177e4 LT	449	f->id = to;
1da177e4 LT	450
add93b61	451	if (tb[TCA_ROUTE4_FROM])
1da177e4	452	f->id = to \| id<<16;
add93b61	453	else if (tb[TCA_ROUTE4_IIF])
1da177e4 LT	454	f->iif = id;
	455
	456	f->handle = nhandle;
	457	f->bkt = b;
1109c005	458	f->tp = tp;
1da177e4	459
add93b61	460	if (tb[TCA_ROUTE4_CLASSID]) {
1587bac4	461	f->res.classid = nla_get_u32(tb[TCA_ROUTE4_CLASSID]);
1da177e4 LT	462	tcf_bind_filter(tp, &f->res, base);
	463	}
	464
1da177e4	465	return 0;
1da177e4 LT	466	}
1da177e4 LT	467
c1b52739	468	static int route4_change(struct net net, struct sk_buff in_skb,
5a7a5555	469	struct tcf_proto *tp, unsigned long base, u32 handle,
7306db38 AA	470	struct nlattr tca, void arg, bool ovr,
7306db38 AA	471	struct netlink_ext_ack *extack)
1da177e4	472	{
1109c005 JF	473	struct route4_head *head = rtnl_dereference(tp->root);
	474	struct route4_filter __rcu **fp;
	475	struct route4_filter fold, f1, pfp, f = NULL;
1da177e4	476	struct route4_bucket *b;
add93b61 PM	477	struct nlattr *opt = tca[TCA_OPTIONS];
add93b61 PM	478	struct nlattr *tb[TCA_ROUTE4_MAX + 1];
1da177e4	479	unsigned int h, th;
1da177e4	480	int err;
1109c005	481	bool new = true;
1da177e4 LT	482
	483	if (opt == NULL)
	484	return handle ? -EINVAL : 0;
	485
fceb6435	486	err = nla_parse_nested(tb, TCA_ROUTE4_MAX, opt, route4_policy, NULL);
cee63723 PM	487	if (err < 0)
cee63723 PM	488	return err;
1da177e4	489
8113c095	490	fold = *arg;
1109c005	491	if (fold && handle && fold->handle != handle)
1da177e4 LT	492	return -EINVAL;
1da177e4 LT	493
1da177e4	494	err = -ENOBUFS;
0da974f4	495	f = kzalloc(sizeof(struct route4_filter), GFP_KERNEL);
1109c005	496	if (!f)
1da177e4	497	goto errout;
1da177e4	498
b9a24bb7 WC	499	err = tcf_exts_init(&f->exts, TCA_ROUTE4_ACT, TCA_ROUTE4_POLICE);
	500	if (err < 0)
	501	goto errout;
	502
1109c005 JF	503	if (fold) {
	504	f->id = fold->id;
	505	f->iif = fold->iif;
	506	f->res = fold->res;
	507	f->handle = fold->handle;
	508
	509	f->tp = fold->tp;
	510	f->bkt = fold->bkt;
	511	new = false;
	512	}
	513
c1b52739	514	err = route4_set_parms(net, tp, base, f, handle, head, tb,
50a56190	515	tca[TCA_RATE], new, ovr, extack);
1da177e4 LT	516	if (err < 0)
	517	goto errout;
	518
1da177e4	519	h = from_hash(f->handle >> 16);
1109c005 JF	520	fp = &f->bkt->ht[h];
	521	for (pfp = rtnl_dereference(*fp);
	522	(f1 = rtnl_dereference(*fp)) != NULL;
	523	fp = &f1->next)
1da177e4 LT	524	if (f->handle < f1->handle)
	525	break;
	526
f36fe1c4	527	tcf_block_netif_keep_dst(tp->chain->block);
1109c005 JF	528	rcu_assign_pointer(f->next, f1);
1109c005 JF	529	rcu_assign_pointer(*fp, f);
1da177e4	530
1109c005 JF	531	if (fold && fold->handle && f->handle != fold->handle) {
	532	th = to_hash(fold->handle);
	533	h = from_hash(fold->handle >> 16);
	534	b = rtnl_dereference(head->table[th]);
cc7ec456	535	if (b) {
1109c005 JF	536	fp = &b->ht[h];
	537	for (pfp = rtnl_dereference(*fp); pfp;
	538	fp = &pfp->next, pfp = rtnl_dereference(*fp)) {
	539	if (pfp == f) {
1da177e4 LT	540	*fp = f->next;
	541	break;
	542	}
	543	}
	544	}
	545	}
1da177e4	546
1109c005	547	route4_reset_fastmap(head);
8113c095	548	*arg = f;
18cdb37e JF	549	if (fold) {
18cdb37e JF	550	tcf_unbind_filter(tp, &fold->res);
3fd51de5	551	tcf_exts_get_net(&fold->exts);
aaa908ff	552	tcf_queue_work(&fold->rwork, route4_delete_filter_work);
18cdb37e	553	}
1da177e4 LT	554	return 0;
	555
	556	errout:
21641c2e WC	557	if (f)
21641c2e WC	558	tcf_exts_destroy(&f->exts);
a51482bd	559	kfree(f);
1da177e4 LT	560	return err;
	561	}
	562
	563	static void route4_walk(struct tcf_proto tp, struct tcf_walker arg)
	564	{
1109c005	565	struct route4_head *head = rtnl_dereference(tp->root);
cc7ec456	566	unsigned int h, h1;
1da177e4 LT	567
	568	if (head == NULL)
	569	arg->stop = 1;
	570
	571	if (arg->stop)
	572	return;
	573
	574	for (h = 0; h <= 256; h++) {
1109c005	575	struct route4_bucket *b = rtnl_dereference(head->table[h]);
1da177e4 LT	576
	577	if (b) {
	578	for (h1 = 0; h1 <= 32; h1++) {
	579	struct route4_filter *f;
	580
1109c005 JF	581	for (f = rtnl_dereference(b->ht[h1]);
	582	f;
	583	f = rtnl_dereference(f->next)) {
1da177e4 LT	584	if (arg->count < arg->skip) {
	585	arg->count++;
	586	continue;
	587	}
8113c095	588	if (arg->fn(tp, f, arg) < 0) {
1da177e4 LT	589	arg->stop = 1;
	590	return;
	591	}
	592	arg->count++;
	593	}
	594	}
	595	}
	596	}
	597	}
	598
8113c095	599	static int route4_dump(struct net net, struct tcf_proto tp, void *fh,
1da177e4 LT	600	struct sk_buff skb, struct tcmsg t)
1da177e4 LT	601	{
8113c095	602	struct route4_filter *f = fh;
4b3550ef	603	struct nlattr *nest;
1da177e4 LT	604	u32 id;
	605
	606	if (f == NULL)
	607	return skb->len;
	608
	609	t->tcm_handle = f->handle;
	610
4b3550ef PM	611	nest = nla_nest_start(skb, TCA_OPTIONS);
	612	if (nest == NULL)
	613	goto nla_put_failure;
1da177e4	614
cc7ec456 ED	615	if (!(f->handle & 0x8000)) {
cc7ec456 ED	616	id = f->id & 0xFF;
1b34ec43 DM	617	if (nla_put_u32(skb, TCA_ROUTE4_TO, id))
1b34ec43 DM	618	goto nla_put_failure;
1da177e4	619	}
cc7ec456	620	if (f->handle & 0x80000000) {
1b34ec43 DM	621	if ((f->handle >> 16) != 0xFFFF &&
	622	nla_put_u32(skb, TCA_ROUTE4_IIF, f->iif))
	623	goto nla_put_failure;
1da177e4	624	} else {
cc7ec456	625	id = f->id >> 16;
1b34ec43 DM	626	if (nla_put_u32(skb, TCA_ROUTE4_FROM, id))
1b34ec43 DM	627	goto nla_put_failure;
1da177e4	628	}
1b34ec43 DM	629	if (f->res.classid &&
	630	nla_put_u32(skb, TCA_ROUTE4_CLASSID, f->res.classid))
	631	goto nla_put_failure;
1da177e4	632
5da57f42	633	if (tcf_exts_dump(skb, &f->exts) < 0)
add93b61	634	goto nla_put_failure;
1da177e4	635
4b3550ef	636	nla_nest_end(skb, nest);
1da177e4	637
5da57f42	638	if (tcf_exts_dump_stats(skb, &f->exts) < 0)
add93b61	639	goto nla_put_failure;
1da177e4 LT	640
	641	return skb->len;
	642
add93b61	643	nla_put_failure:
6ea3b446	644	nla_nest_cancel(skb, nest);
1da177e4 LT	645	return -1;
	646	}
	647
07d79fc7 CW	648	static void route4_bind_class(void *fh, u32 classid, unsigned long cl)
	649	{
	650	struct route4_filter *f = fh;
	651
	652	if (f && f->res.classid == classid)
	653	f->res.class = cl;
	654	}
	655
2eb9d75c	656	static struct tcf_proto_ops cls_route4_ops __read_mostly = {
1da177e4 LT	657	.kind = "route",
	658	.classify = route4_classify,
	659	.init = route4_init,
	660	.destroy = route4_destroy,
	661	.get = route4_get,
1da177e4 LT	662	.change = route4_change,
	663	.delete = route4_delete,
	664	.walk = route4_walk,
	665	.dump = route4_dump,
07d79fc7	666	.bind_class = route4_bind_class,
1da177e4 LT	667	.owner = THIS_MODULE,
	668	};
	669
	670	static int __init init_route4(void)
	671	{
	672	return register_tcf_proto_ops(&cls_route4_ops);
	673	}
	674
	675	static void __exit exit_route4(void)
	676	{
	677	unregister_tcf_proto_ops(&cls_route4_ops);
	678	}
	679
	680	module_init(init_route4)
	681	module_exit(exit_route4)
	682	MODULE_LICENSE("GPL");