[deliverable/linux.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_head		rcu;
};

#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_is_available(&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;
	if (head == NULL)
		goto old_method;

	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;

old_method:
	if (id && (TC_H_MAJ(id) == 0 ||
		   !(TC_H_MAJ(id^tp->q->handle)))) {
		res->classid = id;
		res->class = 0;
		return 0;
	}
	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 unsigned long 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;

	if (!head)
		return 0;

	h1 = to_hash(handle);
	if (h1 > 256)
		return 0;

	h2 = from_hash(handle >> 16);
	if (h2 > 32)
		return 0;

	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 (unsigned long)f;
	}
	return 0;
}

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 rcu_head *head)
{
	struct route4_filter *f = container_of(head, struct route4_filter, rcu);

	tcf_exts_destroy(&f->exts);
	kfree(f);
}

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

	if (head == NULL)
		return true;

	if (!force) {
		for (h1 = 0; h1 <= 256; h1++) {
			if (rcu_access_pointer(head->table[h1]))
				return false;
		}
	}

	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);
					call_rcu(&f->rcu, route4_delete_filter);
				}
			}
			RCU_INIT_POINTER(head->table[h1], NULL);
			kfree_rcu(b, rcu);
		}
	}
	RCU_INIT_POINTER(tp->root, NULL);
	kfree_rcu(head, rcu);
	return true;
}

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

	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);
			call_rcu(&f->rcu, route4_delete_filter);

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

				rt = rtnl_dereference(b->ht[i]);
				if (rt)
					return 0;
			}

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

			return 0;
		}
	}
	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)
{
	u32 id = 0, to = 0, nhandle = 0x8000;
	struct route4_filter *fp;
	unsigned int h1;
	struct route4_bucket *b;
	struct tcf_exts e;
	int err;

	err = tcf_exts_init(&e, TCA_ROUTE4_ACT, TCA_ROUTE4_POLICE);
	if (err < 0)
		return err;
	err = tcf_exts_validate(net, tp, tb, est, &e, ovr);
	if (err < 0)
		goto errout;

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

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

	if (handle && new) {
		nhandle |= handle & 0x7F00;
		if (nhandle != handle)
			goto errout;
	}

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

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

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

	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);
	}

	tcf_exts_change(tp, &f->exts, &e);

	return 0;
errout:
	tcf_exts_destroy(&e);
	return err;
}

static int route4_change(struct net *net, struct sk_buff *in_skb,
		       struct tcf_proto *tp, unsigned long base,
		       u32 handle,
		       struct nlattr **tca,
		       unsigned long *arg, bool ovr)
{
	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);
	if (err < 0)
		return err;

	fold = (struct route4_filter *)*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);
	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;

	netif_keep_dst(qdisc_dev(tp->q));
	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 = (unsigned long)f;
	if (fold) {
		tcf_unbind_filter(tp, &fold->res);
		call_rcu(&fold->rcu, route4_delete_filter);
	}
	return 0;

errout:
	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, (unsigned long)f, arg) < 0) {
						arg->stop = 1;
						return;
					}
					arg->count++;
				}
			}
		}
	}
}

static int route4_dump(struct net *net, struct tcf_proto *tp, unsigned long fh,
		       struct sk_buff *skb, struct tcmsg *t)
{
	struct route4_filter *f = (struct route4_filter *)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 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,
	.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 JF	59	struct tcf_proto *tp;
1109c005 JF	60	struct rcu_head rcu;
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; \
	116	if (tcf_exts_is_available(&f->exts)) { \
	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;
	143	if (head == NULL)
	144	goto old_method;
	145
92101b3b	146	iif = inet_iif(skb);
1da177e4 LT	147
1da177e4 LT	148	h = route4_fastmap_hash(id, iif);
1109c005 JF	149
1109c005 JF	150	spin_lock(&fastmap_lock);
1da177e4 LT	151	if (id == head->fastmap[h].id &&
	152	iif == head->fastmap[h].iif &&
	153	(f = head->fastmap[h].filter) != NULL) {
1109c005 JF	154	if (f == ROUTE4_FAILURE) {
1109c005 JF	155	spin_unlock(&fastmap_lock);
1da177e4	156	goto failure;
1109c005	157	}
1da177e4 LT	158
1da177e4 LT	159	*res = f->res;
1109c005	160	spin_unlock(&fastmap_lock);
1da177e4 LT	161	return 0;
1da177e4 LT	162	}
1109c005	163	spin_unlock(&fastmap_lock);
1da177e4 LT	164
	165	h = route4_hash_to(id);
	166
	167	restart:
1109c005	168	b = rcu_dereference_bh(head->table[h]);
cc7ec456	169	if (b) {
1109c005 JF	170	for (f = rcu_dereference_bh(b->ht[route4_hash_from(id)]);
	171	f;
	172	f = rcu_dereference_bh(f->next))
1da177e4 LT	173	if (f->id == id)
	174	ROUTE4_APPLY_RESULT();
	175
1109c005 JF	176	for (f = rcu_dereference_bh(b->ht[route4_hash_iif(iif)]);
	177	f;
	178	f = rcu_dereference_bh(f->next))
1da177e4 LT	179	if (f->iif == iif)
	180	ROUTE4_APPLY_RESULT();
	181
1109c005 JF	182	for (f = rcu_dereference_bh(b->ht[route4_hash_wild()]);
	183	f;
	184	f = rcu_dereference_bh(f->next))
1da177e4	185	ROUTE4_APPLY_RESULT();
1da177e4 LT	186	}
	187	if (h < 256) {
	188	h = 256;
	189	id &= ~0xFFFF;
	190	goto restart;
	191	}
	192
	193	if (!dont_cache)
	194	route4_set_fastmap(head, id, iif, ROUTE4_FAILURE);
	195	failure:
	196	return -1;
	197
	198	old_method:
	199	if (id && (TC_H_MAJ(id) == 0 \|\|
	200	!(TC_H_MAJ(id^tp->q->handle)))) {
	201	res->classid = id;
	202	res->class = 0;
	203	return 0;
	204	}
	205	return -1;
	206	}
	207
	208	static inline u32 to_hash(u32 id)
	209	{
cc7ec456 ED	210	u32 h = id & 0xFF;
	211
	212	if (id & 0x8000)
1da177e4 LT	213	h += 256;
	214	return h;
	215	}
	216
	217	static inline u32 from_hash(u32 id)
	218	{
	219	id &= 0xFFFF;
	220	if (id == 0xFFFF)
	221	return 32;
	222	if (!(id & 0x8000)) {
	223	if (id > 255)
	224	return 256;
cc7ec456	225	return id & 0xF;
1da177e4	226	}
cc7ec456	227	return 16 + (id & 0xF);
1da177e4 LT	228	}
	229
	230	static unsigned long route4_get(struct tcf_proto *tp, u32 handle)
	231	{
1109c005	232	struct route4_head *head = rtnl_dereference(tp->root);
1da177e4 LT	233	struct route4_bucket *b;
1da177e4 LT	234	struct route4_filter *f;
cc7ec456	235	unsigned int h1, h2;
1da177e4 LT	236
	237	if (!head)
	238	return 0;
	239
	240	h1 = to_hash(handle);
	241	if (h1 > 256)
	242	return 0;
	243
cc7ec456	244	h2 = from_hash(handle >> 16);
1da177e4 LT	245	if (h2 > 32)
	246	return 0;
	247
1109c005	248	b = rtnl_dereference(head->table[h1]);
cc7ec456	249	if (b) {
1109c005 JF	250	for (f = rtnl_dereference(b->ht[h2]);
	251	f;
	252	f = rtnl_dereference(f->next))
1da177e4 LT	253	if (f->handle == handle)
	254	return (unsigned long)f;
	255	}
	256	return 0;
	257	}
	258
1da177e4 LT	259	static int route4_init(struct tcf_proto *tp)
1da177e4 LT	260	{
a05c2d11 WC	261	struct route4_head *head;
	262
	263	head = kzalloc(sizeof(struct route4_head), GFP_KERNEL);
	264	if (head == NULL)
	265	return -ENOBUFS;
	266
	267	rcu_assign_pointer(tp->root, head);
1da177e4 LT	268	return 0;
	269	}
	270
cc7ec456	271	static void
1109c005	272	route4_delete_filter(struct rcu_head *head)
1da177e4	273	{
1109c005	274	struct route4_filter *f = container_of(head, struct route4_filter, rcu);
1109c005	275
18d0264f	276	tcf_exts_destroy(&f->exts);
1da177e4 LT	277	kfree(f);
	278	}
	279
1e052be6	280	static bool route4_destroy(struct tcf_proto *tp, bool force)
1da177e4	281	{
1109c005	282	struct route4_head *head = rtnl_dereference(tp->root);
1da177e4 LT	283	int h1, h2;
	284
	285	if (head == NULL)
1e052be6 CW	286	return true;
	287
	288	if (!force) {
	289	for (h1 = 0; h1 <= 256; h1++) {
	290	if (rcu_access_pointer(head->table[h1]))
	291	return false;
	292	}
	293	}
1da177e4	294
cc7ec456	295	for (h1 = 0; h1 <= 256; h1++) {
1da177e4 LT	296	struct route4_bucket *b;
1da177e4 LT	297
1109c005	298	b = rtnl_dereference(head->table[h1]);
cc7ec456 ED	299	if (b) {
cc7ec456 ED	300	for (h2 = 0; h2 <= 32; h2++) {
1da177e4 LT	301	struct route4_filter *f;
1da177e4 LT	302
1109c005 JF	303	while ((f = rtnl_dereference(b->ht[h2])) != NULL) {
	304	struct route4_filter *next;
	305
	306	next = rtnl_dereference(f->next);
	307	RCU_INIT_POINTER(b->ht[h2], next);
18cdb37e	308	tcf_unbind_filter(tp, &f->res);
1109c005	309	call_rcu(&f->rcu, route4_delete_filter);
1da177e4 LT	310	}
1da177e4 LT	311	}
1109c005 JF	312	RCU_INIT_POINTER(head->table[h1], NULL);
1109c005 JF	313	kfree_rcu(b, rcu);
1da177e4 LT	314	}
1da177e4 LT	315	}
1109c005 JF	316	RCU_INIT_POINTER(tp->root, NULL);
1109c005 JF	317	kfree_rcu(head, rcu);
1e052be6	318	return true;
1da177e4 LT	319	}
	320
	321	static int route4_delete(struct tcf_proto *tp, unsigned long arg)
	322	{
1109c005 JF	323	struct route4_head *head = rtnl_dereference(tp->root);
	324	struct route4_filter f = (struct route4_filter )arg;
	325	struct route4_filter __rcu **fp;
	326	struct route4_filter *nf;
1da177e4	327	struct route4_bucket *b;
1109c005	328	unsigned int h = 0;
1da177e4 LT	329	int i;
	330
	331	if (!head \|\| !f)
	332	return -EINVAL;
	333
	334	h = f->handle;
	335	b = f->bkt;
	336
1109c005 JF	337	fp = &b->ht[from_hash(h >> 16)];
	338	for (nf = rtnl_dereference(*fp); nf;
	339	fp = &nf->next, nf = rtnl_dereference(*fp)) {
	340	if (nf == f) {
	341	/* unlink it */
	342	RCU_INIT_POINTER(*fp, rtnl_dereference(f->next));
1da177e4	343
1109c005 JF	344	/* Remove any fastmap lookups that might ref filter
	345	* notice we unlink'd the filter so we can't get it
	346	* back in the fastmap.
	347	*/
	348	route4_reset_fastmap(head);
1da177e4	349
1109c005	350	/* Delete it */
18cdb37e	351	tcf_unbind_filter(tp, &f->res);
1109c005	352	call_rcu(&f->rcu, route4_delete_filter);
1da177e4	353
1109c005 JF	354	/* Strip RTNL protected tree */
	355	for (i = 0; i <= 32; i++) {
	356	struct route4_filter *rt;
	357
	358	rt = rtnl_dereference(b->ht[i]);
	359	if (rt)
1da177e4	360	return 0;
1109c005	361	}
1da177e4 LT	362
1da177e4 LT	363	/* OK, session has no flows */
1109c005 JF	364	RCU_INIT_POINTER(head->table[to_hash(h)], NULL);
1109c005 JF	365	kfree_rcu(b, rcu);
1da177e4	366
1da177e4 LT	367	return 0;
	368	}
	369	}
	370	return 0;
	371	}
	372
6fa8c014 PM	373	static const struct nla_policy route4_policy[TCA_ROUTE4_MAX + 1] = {
	374	[TCA_ROUTE4_CLASSID] = { .type = NLA_U32 },
	375	[TCA_ROUTE4_TO] = { .type = NLA_U32 },
	376	[TCA_ROUTE4_FROM] = { .type = NLA_U32 },
	377	[TCA_ROUTE4_IIF] = { .type = NLA_U32 },
	378	};
	379
c1b52739 BL	380	static int route4_set_parms(struct net net, struct tcf_proto tp,
	381	unsigned long base, struct route4_filter *f,
	382	u32 handle, struct route4_head *head,
2f7ef2f8 CW	383	struct nlattr *tb, struct nlattr est, int new,
2f7ef2f8 CW	384	bool ovr)
1da177e4	385	{
1da177e4 LT	386	u32 id = 0, to = 0, nhandle = 0x8000;
	387	struct route4_filter *fp;
	388	unsigned int h1;
	389	struct route4_bucket *b;
	390	struct tcf_exts e;
b9a24bb7	391	int err;
1da177e4	392
b9a24bb7	393	err = tcf_exts_init(&e, TCA_ROUTE4_ACT, TCA_ROUTE4_POLICE);
1da177e4 LT	394	if (err < 0)
1da177e4 LT	395	return err;
b9a24bb7 WC	396	err = tcf_exts_validate(net, tp, tb, est, &e, ovr);
	397	if (err < 0)
	398	goto errout;
1da177e4 LT	399
1da177e4 LT	400	err = -EINVAL;
add93b61	401	if (tb[TCA_ROUTE4_TO]) {
1da177e4 LT	402	if (new && handle & 0x8000)
1da177e4 LT	403	goto errout;
1587bac4	404	to = nla_get_u32(tb[TCA_ROUTE4_TO]);
1da177e4 LT	405	if (to > 0xFF)
	406	goto errout;
	407	nhandle = to;
	408	}
	409
add93b61 PM	410	if (tb[TCA_ROUTE4_FROM]) {
add93b61 PM	411	if (tb[TCA_ROUTE4_IIF])
1da177e4	412	goto errout;
1587bac4	413	id = nla_get_u32(tb[TCA_ROUTE4_FROM]);
1da177e4 LT	414	if (id > 0xFF)
	415	goto errout;
	416	nhandle \|= id << 16;
add93b61	417	} else if (tb[TCA_ROUTE4_IIF]) {
1587bac4	418	id = nla_get_u32(tb[TCA_ROUTE4_IIF]);
1da177e4 LT	419	if (id > 0x7FFF)
	420	goto errout;
	421	nhandle \|= (id \| 0x8000) << 16;
	422	} else
	423	nhandle \|= 0xFFFF << 16;
	424
	425	if (handle && new) {
	426	nhandle \|= handle & 0x7F00;
	427	if (nhandle != handle)
	428	goto errout;
	429	}
	430
	431	h1 = to_hash(nhandle);
1109c005	432	b = rtnl_dereference(head->table[h1]);
cc7ec456	433	if (!b) {
1da177e4	434	err = -ENOBUFS;
0da974f4	435	b = kzalloc(sizeof(struct route4_bucket), GFP_KERNEL);
1da177e4 LT	436	if (b == NULL)
1da177e4 LT	437	goto errout;
1da177e4	438
1109c005	439	rcu_assign_pointer(head->table[h1], b);
1da177e4 LT	440	} else {
1da177e4 LT	441	unsigned int h2 = from_hash(nhandle >> 16);
cc7ec456	442
1da177e4	443	err = -EEXIST;
1109c005 JF	444	for (fp = rtnl_dereference(b->ht[h2]);
	445	fp;
	446	fp = rtnl_dereference(fp->next))
1da177e4 LT	447	if (fp->handle == f->handle)
	448	goto errout;
	449	}
	450
add93b61	451	if (tb[TCA_ROUTE4_TO])
1da177e4 LT	452	f->id = to;
1da177e4 LT	453
add93b61	454	if (tb[TCA_ROUTE4_FROM])
1da177e4	455	f->id = to \| id<<16;
add93b61	456	else if (tb[TCA_ROUTE4_IIF])
1da177e4 LT	457	f->iif = id;
	458
	459	f->handle = nhandle;
	460	f->bkt = b;
1109c005	461	f->tp = tp;
1da177e4	462
add93b61	463	if (tb[TCA_ROUTE4_CLASSID]) {
1587bac4	464	f->res.classid = nla_get_u32(tb[TCA_ROUTE4_CLASSID]);
1da177e4 LT	465	tcf_bind_filter(tp, &f->res, base);
	466	}
	467
	468	tcf_exts_change(tp, &f->exts, &e);
	469
	470	return 0;
	471	errout:
18d0264f	472	tcf_exts_destroy(&e);
1da177e4 LT	473	return err;
	474	}
	475
c1b52739	476	static int route4_change(struct net net, struct sk_buff in_skb,
af4c6641	477	struct tcf_proto *tp, unsigned long base,
1da177e4	478	u32 handle,
add93b61	479	struct nlattr **tca,
2f7ef2f8	480	unsigned long *arg, bool ovr)
1da177e4	481	{
1109c005 JF	482	struct route4_head *head = rtnl_dereference(tp->root);
	483	struct route4_filter __rcu **fp;
	484	struct route4_filter fold, f1, pfp, f = NULL;
1da177e4	485	struct route4_bucket *b;
add93b61 PM	486	struct nlattr *opt = tca[TCA_OPTIONS];
add93b61 PM	487	struct nlattr *tb[TCA_ROUTE4_MAX + 1];
1da177e4	488	unsigned int h, th;
1da177e4	489	int err;
1109c005	490	bool new = true;
1da177e4 LT	491
	492	if (opt == NULL)
	493	return handle ? -EINVAL : 0;
	494
6fa8c014	495	err = nla_parse_nested(tb, TCA_ROUTE4_MAX, opt, route4_policy);
cee63723 PM	496	if (err < 0)
cee63723 PM	497	return err;
1da177e4	498
1109c005 JF	499	fold = (struct route4_filter )arg;
1109c005 JF	500	if (fold && handle && fold->handle != handle)
1da177e4 LT	501	return -EINVAL;
1da177e4 LT	502
1da177e4	503	err = -ENOBUFS;
0da974f4	504	f = kzalloc(sizeof(struct route4_filter), GFP_KERNEL);
1109c005	505	if (!f)
1da177e4	506	goto errout;
1da177e4	507
b9a24bb7 WC	508	err = tcf_exts_init(&f->exts, TCA_ROUTE4_ACT, TCA_ROUTE4_POLICE);
	509	if (err < 0)
	510	goto errout;
	511
1109c005 JF	512	if (fold) {
	513	f->id = fold->id;
	514	f->iif = fold->iif;
	515	f->res = fold->res;
	516	f->handle = fold->handle;
	517
	518	f->tp = fold->tp;
	519	f->bkt = fold->bkt;
	520	new = false;
	521	}
	522
c1b52739	523	err = route4_set_parms(net, tp, base, f, handle, head, tb,
1109c005	524	tca[TCA_RATE], new, ovr);
1da177e4 LT	525	if (err < 0)
	526	goto errout;
	527
1da177e4	528	h = from_hash(f->handle >> 16);
1109c005 JF	529	fp = &f->bkt->ht[h];
	530	for (pfp = rtnl_dereference(*fp);
	531	(f1 = rtnl_dereference(*fp)) != NULL;
	532	fp = &f1->next)
1da177e4 LT	533	if (f->handle < f1->handle)
	534	break;
	535
02875878	536	netif_keep_dst(qdisc_dev(tp->q));
1109c005 JF	537	rcu_assign_pointer(f->next, f1);
1109c005 JF	538	rcu_assign_pointer(*fp, f);
1da177e4	539
1109c005 JF	540	if (fold && fold->handle && f->handle != fold->handle) {
	541	th = to_hash(fold->handle);
	542	h = from_hash(fold->handle >> 16);
	543	b = rtnl_dereference(head->table[th]);
cc7ec456	544	if (b) {
1109c005 JF	545	fp = &b->ht[h];
	546	for (pfp = rtnl_dereference(*fp); pfp;
	547	fp = &pfp->next, pfp = rtnl_dereference(*fp)) {
	548	if (pfp == f) {
1da177e4 LT	549	*fp = f->next;
	550	break;
	551	}
	552	}
	553	}
	554	}
1da177e4	555
1109c005	556	route4_reset_fastmap(head);
1da177e4	557	*arg = (unsigned long)f;
18cdb37e JF	558	if (fold) {
18cdb37e JF	559	tcf_unbind_filter(tp, &fold->res);
1109c005	560	call_rcu(&fold->rcu, route4_delete_filter);
18cdb37e	561	}
1da177e4 LT	562	return 0;
	563
	564	errout:
b9a24bb7	565	tcf_exts_destroy(&f->exts);
a51482bd	566	kfree(f);
1da177e4 LT	567	return err;
	568	}
	569
	570	static void route4_walk(struct tcf_proto tp, struct tcf_walker arg)
	571	{
1109c005	572	struct route4_head *head = rtnl_dereference(tp->root);
cc7ec456	573	unsigned int h, h1;
1da177e4 LT	574
	575	if (head == NULL)
	576	arg->stop = 1;
	577
	578	if (arg->stop)
	579	return;
	580
	581	for (h = 0; h <= 256; h++) {
1109c005	582	struct route4_bucket *b = rtnl_dereference(head->table[h]);
1da177e4 LT	583
	584	if (b) {
	585	for (h1 = 0; h1 <= 32; h1++) {
	586	struct route4_filter *f;
	587
1109c005 JF	588	for (f = rtnl_dereference(b->ht[h1]);
	589	f;
	590	f = rtnl_dereference(f->next)) {
1da177e4 LT	591	if (arg->count < arg->skip) {
	592	arg->count++;
	593	continue;
	594	}
	595	if (arg->fn(tp, (unsigned long)f, arg) < 0) {
	596	arg->stop = 1;
	597	return;
	598	}
	599	arg->count++;
	600	}
	601	}
	602	}
	603	}
	604	}
	605
832d1d5b	606	static int route4_dump(struct net net, struct tcf_proto tp, unsigned long fh,
1da177e4 LT	607	struct sk_buff skb, struct tcmsg t)
1da177e4 LT	608	{
cc7ec456	609	struct route4_filter f = (struct route4_filter )fh;
4b3550ef	610	struct nlattr *nest;
1da177e4 LT	611	u32 id;
	612
	613	if (f == NULL)
	614	return skb->len;
	615
	616	t->tcm_handle = f->handle;
	617
4b3550ef PM	618	nest = nla_nest_start(skb, TCA_OPTIONS);
	619	if (nest == NULL)
	620	goto nla_put_failure;
1da177e4	621
cc7ec456 ED	622	if (!(f->handle & 0x8000)) {
cc7ec456 ED	623	id = f->id & 0xFF;
1b34ec43 DM	624	if (nla_put_u32(skb, TCA_ROUTE4_TO, id))
1b34ec43 DM	625	goto nla_put_failure;
1da177e4	626	}
cc7ec456	627	if (f->handle & 0x80000000) {
1b34ec43 DM	628	if ((f->handle >> 16) != 0xFFFF &&
	629	nla_put_u32(skb, TCA_ROUTE4_IIF, f->iif))
	630	goto nla_put_failure;
1da177e4	631	} else {
cc7ec456	632	id = f->id >> 16;
1b34ec43 DM	633	if (nla_put_u32(skb, TCA_ROUTE4_FROM, id))
1b34ec43 DM	634	goto nla_put_failure;
1da177e4	635	}
1b34ec43 DM	636	if (f->res.classid &&
	637	nla_put_u32(skb, TCA_ROUTE4_CLASSID, f->res.classid))
	638	goto nla_put_failure;
1da177e4	639
5da57f42	640	if (tcf_exts_dump(skb, &f->exts) < 0)
add93b61	641	goto nla_put_failure;
1da177e4	642
4b3550ef	643	nla_nest_end(skb, nest);
1da177e4	644
5da57f42	645	if (tcf_exts_dump_stats(skb, &f->exts) < 0)
add93b61	646	goto nla_put_failure;
1da177e4 LT	647
	648	return skb->len;
	649
add93b61	650	nla_put_failure:
6ea3b446	651	nla_nest_cancel(skb, nest);
1da177e4 LT	652	return -1;
	653	}
	654
2eb9d75c	655	static struct tcf_proto_ops cls_route4_ops __read_mostly = {
1da177e4 LT	656	.kind = "route",
	657	.classify = route4_classify,
	658	.init = route4_init,
	659	.destroy = route4_destroy,
	660	.get = route4_get,
1da177e4 LT	661	.change = route4_change,
	662	.delete = route4_delete,
	663	.walk = route4_walk,
	664	.dump = route4_dump,
	665	.owner = THIS_MODULE,
	666	};
	667
	668	static int __init init_route4(void)
	669	{
	670	return register_tcf_proto_ops(&cls_route4_ops);
	671	}
	672
	673	static void __exit exit_route4(void)
	674	{
	675	unregister_tcf_proto_ops(&cls_route4_ops);
	676	}
	677
	678	module_init(init_route4)
	679	module_exit(exit_route4)
	680	MODULE_LICENSE("GPL");