[mirror_ubuntu-bionic-kernel.git] / net / sched / cls_tcindex.c

/*
 * net/sched/cls_tcindex.c	Packet classifier for skb->tc_index
 *
 * Written 1998,1999 by Werner Almesberger, EPFL ICA
 */

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

/*
 * Passing parameters to the root seems to be done more awkwardly than really
 * necessary. At least, u32 doesn't seem to use such dirty hacks. To be
 * verified. FIXME.
 */

#define PERFECT_HASH_THRESHOLD	64	/* use perfect hash if not bigger */
#define DEFAULT_HASH_SIZE	64	/* optimized for diffserv */


struct tcindex_filter_result {
	struct tcf_exts		exts;
	struct tcf_result	res;
};

struct tcindex_filter {
	u16 key;
	struct tcindex_filter_result result;
	struct tcindex_filter *next;
};


struct tcindex_data {
	struct tcindex_filter_result *perfect; /* perfect hash; NULL if none */
	struct tcindex_filter **h; /* imperfect hash; only used if !perfect;
				      NULL if unused */
	u16 mask;		/* AND key with mask */
	int shift;		/* shift ANDed key to the right */
	int hash;		/* hash table size; 0 if undefined */
	int alloc_hash;		/* allocated size */
	int fall_through;	/* 0: only classify if explicit match */
};

static inline int
tcindex_filter_is_set(struct tcindex_filter_result *r)
{
	return tcf_exts_is_predicative(&r->exts) || r->res.classid;
}

static struct tcindex_filter_result *
tcindex_lookup(struct tcindex_data *p, u16 key)
{
	struct tcindex_filter *f;

	if (p->perfect)
		return tcindex_filter_is_set(p->perfect + key) ?
			p->perfect + key : NULL;
	else if (p->h) {
		for (f = p->h[key % p->hash]; f; f = f->next)
			if (f->key == key)
				return &f->result;
	}

	return NULL;
}


static int tcindex_classify(struct sk_buff *skb, const struct tcf_proto *tp,
			    struct tcf_result *res)
{
	struct tcindex_data *p = tp->root;
	struct tcindex_filter_result *f;
	int key = (skb->tc_index & p->mask) >> p->shift;

	pr_debug("tcindex_classify(skb %p,tp %p,res %p),p %p\n",
		 skb, tp, res, p);

	f = tcindex_lookup(p, key);
	if (!f) {
		if (!p->fall_through)
			return -1;
		res->classid = TC_H_MAKE(TC_H_MAJ(tp->q->handle), key);
		res->class = 0;
		pr_debug("alg 0x%x\n", res->classid);
		return 0;
	}
	*res = f->res;
	pr_debug("map 0x%x\n", res->classid);

	return tcf_exts_exec(skb, &f->exts, res);
}


static unsigned long tcindex_get(struct tcf_proto *tp, u32 handle)
{
	struct tcindex_data *p = tp->root;
	struct tcindex_filter_result *r;

	pr_debug("tcindex_get(tp %p,handle 0x%08x)\n", tp, handle);
	if (p->perfect && handle >= p->alloc_hash)
		return 0;
	r = tcindex_lookup(p, handle);
	return r && tcindex_filter_is_set(r) ? (unsigned long) r : 0UL;
}


static void tcindex_put(struct tcf_proto *tp, unsigned long f)
{
	pr_debug("tcindex_put(tp %p,f 0x%lx)\n", tp, f);
}


static int tcindex_init(struct tcf_proto *tp)
{
	struct tcindex_data *p;

	pr_debug("tcindex_init(tp %p)\n", tp);
	p = kzalloc(sizeof(struct tcindex_data), GFP_KERNEL);
	if (!p)
		return -ENOMEM;

	p->mask = 0xffff;
	p->hash = DEFAULT_HASH_SIZE;
	p->fall_through = 1;

	tp->root = p;
	return 0;
}


static int
__tcindex_delete(struct tcf_proto *tp, unsigned long arg, int lock)
{
	struct tcindex_data *p = tp->root;
	struct tcindex_filter_result *r = (struct tcindex_filter_result *) arg;
	struct tcindex_filter *f = NULL;

	pr_debug("tcindex_delete(tp %p,arg 0x%lx),p %p,f %p\n", tp, arg, p, f);
	if (p->perfect) {
		if (!r->res.class)
			return -ENOENT;
	} else {
		int i;
		struct tcindex_filter **walk = NULL;

		for (i = 0; i < p->hash; i++)
			for (walk = p->h+i; *walk; walk = &(*walk)->next)
				if (&(*walk)->result == r)
					goto found;
		return -ENOENT;

found:
		f = *walk;
		if (lock)
			tcf_tree_lock(tp);
		*walk = f->next;
		if (lock)
			tcf_tree_unlock(tp);
	}
	tcf_unbind_filter(tp, &r->res);
	tcf_exts_destroy(tp, &r->exts);
	kfree(f);
	return 0;
}

static int tcindex_delete(struct tcf_proto *tp, unsigned long arg)
{
	return __tcindex_delete(tp, arg, 1);
}

static inline int
valid_perfect_hash(struct tcindex_data *p)
{
	return  p->hash > (p->mask >> p->shift);
}

static const struct nla_policy tcindex_policy[TCA_TCINDEX_MAX + 1] = {
	[TCA_TCINDEX_HASH]		= { .type = NLA_U32 },
	[TCA_TCINDEX_MASK]		= { .type = NLA_U16 },
	[TCA_TCINDEX_SHIFT]		= { .type = NLA_U32 },
	[TCA_TCINDEX_FALL_THROUGH]	= { .type = NLA_U32 },
	[TCA_TCINDEX_CLASSID]		= { .type = NLA_U32 },
};

static int
tcindex_set_parms(struct net *net, struct tcf_proto *tp, unsigned long base,
		  u32 handle, struct tcindex_data *p,
		  struct tcindex_filter_result *r, struct nlattr **tb,
		  struct nlattr *est, bool ovr)
{
	int err, balloc = 0;
	struct tcindex_filter_result new_filter_result, *old_r = r;
	struct tcindex_filter_result cr;
	struct tcindex_data cp;
	struct tcindex_filter *f = NULL; /* make gcc behave */
	struct tcf_exts e;

	tcf_exts_init(&e, TCA_TCINDEX_ACT, TCA_TCINDEX_POLICE);
	err = tcf_exts_validate(net, tp, tb, est, &e, ovr);
	if (err < 0)
		return err;

	memcpy(&cp, p, sizeof(cp));
	memset(&new_filter_result, 0, sizeof(new_filter_result));
	tcf_exts_init(&new_filter_result.exts, TCA_TCINDEX_ACT, TCA_TCINDEX_POLICE);

	if (old_r)
		memcpy(&cr, r, sizeof(cr));
	else {
		memset(&cr, 0, sizeof(cr));
		tcf_exts_init(&cr.exts, TCA_TCINDEX_ACT, TCA_TCINDEX_POLICE);
	}

	if (tb[TCA_TCINDEX_HASH])
		cp.hash = nla_get_u32(tb[TCA_TCINDEX_HASH]);

	if (tb[TCA_TCINDEX_MASK])
		cp.mask = nla_get_u16(tb[TCA_TCINDEX_MASK]);

	if (tb[TCA_TCINDEX_SHIFT])
		cp.shift = nla_get_u32(tb[TCA_TCINDEX_SHIFT]);

	err = -EBUSY;
	/* Hash already allocated, make sure that we still meet the
	 * requirements for the allocated hash.
	 */
	if (cp.perfect) {
		if (!valid_perfect_hash(&cp) ||
		    cp.hash > cp.alloc_hash)
			goto errout;
	} else if (cp.h && cp.hash != cp.alloc_hash)
		goto errout;

	err = -EINVAL;
	if (tb[TCA_TCINDEX_FALL_THROUGH])
		cp.fall_through = nla_get_u32(tb[TCA_TCINDEX_FALL_THROUGH]);

	if (!cp.hash) {
		/* Hash not specified, use perfect hash if the upper limit
		 * of the hashing index is below the threshold.
		 */
		if ((cp.mask >> cp.shift) < PERFECT_HASH_THRESHOLD)
			cp.hash = (cp.mask >> cp.shift) + 1;
		else
			cp.hash = DEFAULT_HASH_SIZE;
	}

	if (!cp.perfect && !cp.h)
		cp.alloc_hash = cp.hash;

	/* Note: this could be as restrictive as if (handle & ~(mask >> shift))
	 * but then, we'd fail handles that may become valid after some future
	 * mask change. While this is extremely unlikely to ever matter,
	 * the check below is safer (and also more backwards-compatible).
	 */
	if (cp.perfect || valid_perfect_hash(&cp))
		if (handle >= cp.alloc_hash)
			goto errout;


	err = -ENOMEM;
	if (!cp.perfect && !cp.h) {
		if (valid_perfect_hash(&cp)) {
			cp.perfect = kcalloc(cp.hash, sizeof(*r), GFP_KERNEL);
			if (!cp.perfect)
				goto errout;
			balloc = 1;
		} else {
			cp.h = kcalloc(cp.hash, sizeof(f), GFP_KERNEL);
			if (!cp.h)
				goto errout;
			balloc = 2;
		}
	}

	if (cp.perfect)
		r = cp.perfect + handle;
	else
		r = tcindex_lookup(&cp, handle) ? : &new_filter_result;

	if (r == &new_filter_result) {
		f = kzalloc(sizeof(*f), GFP_KERNEL);
		if (!f)
			goto errout_alloc;
	}

	if (tb[TCA_TCINDEX_CLASSID]) {
		cr.res.classid = nla_get_u32(tb[TCA_TCINDEX_CLASSID]);
		tcf_bind_filter(tp, &cr.res, base);
	}

	tcf_exts_change(tp, &cr.exts, &e);

	tcf_tree_lock(tp);
	if (old_r && old_r != r)
		memset(old_r, 0, sizeof(*old_r));

	memcpy(p, &cp, sizeof(cp));
	memcpy(r, &cr, sizeof(cr));

	if (r == &new_filter_result) {
		struct tcindex_filter **fp;

		f->key = handle;
		f->result = new_filter_result;
		f->next = NULL;
		for (fp = p->h+(handle % p->hash); *fp; fp = &(*fp)->next)
			/* nothing */;
		*fp = f;
	}
	tcf_tree_unlock(tp);

	return 0;

errout_alloc:
	if (balloc == 1)
		kfree(cp.perfect);
	else if (balloc == 2)
		kfree(cp.h);
errout:
	tcf_exts_destroy(tp, &e);
	return err;
}

static int
tcindex_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 nlattr *opt = tca[TCA_OPTIONS];
	struct nlattr *tb[TCA_TCINDEX_MAX + 1];
	struct tcindex_data *p = tp->root;
	struct tcindex_filter_result *r = (struct tcindex_filter_result *) *arg;
	int err;

	pr_debug("tcindex_change(tp %p,handle 0x%08x,tca %p,arg %p),opt %p,"
	    "p %p,r %p,*arg 0x%lx\n",
	    tp, handle, tca, arg, opt, p, r, arg ? *arg : 0L);

	if (!opt)
		return 0;

	err = nla_parse_nested(tb, TCA_TCINDEX_MAX, opt, tcindex_policy);
	if (err < 0)
		return err;

	return tcindex_set_parms(net, tp, base, handle, p, r, tb,
				 tca[TCA_RATE], ovr);
}


static void tcindex_walk(struct tcf_proto *tp, struct tcf_walker *walker)
{
	struct tcindex_data *p = tp->root;
	struct tcindex_filter *f, *next;
	int i;

	pr_debug("tcindex_walk(tp %p,walker %p),p %p\n", tp, walker, p);
	if (p->perfect) {
		for (i = 0; i < p->hash; i++) {
			if (!p->perfect[i].res.class)
				continue;
			if (walker->count >= walker->skip) {
				if (walker->fn(tp,
				    (unsigned long) (p->perfect+i), walker)
				     < 0) {
					walker->stop = 1;
					return;
				}
			}
			walker->count++;
		}
	}
	if (!p->h)
		return;
	for (i = 0; i < p->hash; i++) {
		for (f = p->h[i]; f; f = next) {
			next = f->next;
			if (walker->count >= walker->skip) {
				if (walker->fn(tp, (unsigned long) &f->result,
				    walker) < 0) {
					walker->stop = 1;
					return;
				}
			}
			walker->count++;
		}
	}
}


static int tcindex_destroy_element(struct tcf_proto *tp,
    unsigned long arg, struct tcf_walker *walker)
{
	return __tcindex_delete(tp, arg, 0);
}


static void tcindex_destroy(struct tcf_proto *tp)
{
	struct tcindex_data *p = tp->root;
	struct tcf_walker walker;

	pr_debug("tcindex_destroy(tp %p),p %p\n", tp, p);
	walker.count = 0;
	walker.skip = 0;
	walker.fn = &tcindex_destroy_element;
	tcindex_walk(tp, &walker);
	kfree(p->perfect);
	kfree(p->h);
	kfree(p);
	tp->root = NULL;
}


static int tcindex_dump(struct net *net, struct tcf_proto *tp, unsigned long fh,
    struct sk_buff *skb, struct tcmsg *t)
{
	struct tcindex_data *p = tp->root;
	struct tcindex_filter_result *r = (struct tcindex_filter_result *) fh;
	unsigned char *b = skb_tail_pointer(skb);
	struct nlattr *nest;

	pr_debug("tcindex_dump(tp %p,fh 0x%lx,skb %p,t %p),p %p,r %p,b %p\n",
		 tp, fh, skb, t, p, r, b);
	pr_debug("p->perfect %p p->h %p\n", p->perfect, p->h);

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

	if (!fh) {
		t->tcm_handle = ~0; /* whatever ... */
		if (nla_put_u32(skb, TCA_TCINDEX_HASH, p->hash) ||
		    nla_put_u16(skb, TCA_TCINDEX_MASK, p->mask) ||
		    nla_put_u32(skb, TCA_TCINDEX_SHIFT, p->shift) ||
		    nla_put_u32(skb, TCA_TCINDEX_FALL_THROUGH, p->fall_through))
			goto nla_put_failure;
		nla_nest_end(skb, nest);
	} else {
		if (p->perfect) {
			t->tcm_handle = r-p->perfect;
		} else {
			struct tcindex_filter *f;
			int i;

			t->tcm_handle = 0;
			for (i = 0; !t->tcm_handle && i < p->hash; i++) {
				for (f = p->h[i]; !t->tcm_handle && f;
				     f = f->next) {
					if (&f->result == r)
						t->tcm_handle = f->key;
				}
			}
		}
		pr_debug("handle = %d\n", t->tcm_handle);
		if (r->res.class &&
		    nla_put_u32(skb, TCA_TCINDEX_CLASSID, r->res.classid))
			goto nla_put_failure;

		if (tcf_exts_dump(skb, &r->exts) < 0)
			goto nla_put_failure;
		nla_nest_end(skb, nest);

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

	return skb->len;

nla_put_failure:
	nlmsg_trim(skb, b);
	return -1;
}

static struct tcf_proto_ops cls_tcindex_ops __read_mostly = {
	.kind		=	"tcindex",
	.classify	=	tcindex_classify,
	.init		=	tcindex_init,
	.destroy	=	tcindex_destroy,
	.get		=	tcindex_get,
	.put		=	tcindex_put,
	.change		=	tcindex_change,
	.delete		=	tcindex_delete,
	.walk		=	tcindex_walk,
	.dump		=	tcindex_dump,
	.owner		=	THIS_MODULE,
};

static int __init init_tcindex(void)
{
	return register_tcf_proto_ops(&cls_tcindex_ops);
}

static void __exit exit_tcindex(void)
{
	unregister_tcf_proto_ops(&cls_tcindex_ops);
}

module_init(init_tcindex)
module_exit(exit_tcindex)
MODULE_LICENSE("GPL");
Commit	Line	Data
1da177e4 LT	1	/*
	2	* net/sched/cls_tcindex.c Packet classifier for skb->tc_index
	3	*
	4	* Written 1998,1999 by Werner Almesberger, EPFL ICA
	5	*/
	6
1da177e4 LT	7	#include <linux/module.h>
	8	#include <linux/types.h>
	9	#include <linux/kernel.h>
	10	#include <linux/skbuff.h>
	11	#include <linux/errno.h>
5a0e3ad6	12	#include <linux/slab.h>
1da177e4	13	#include <net/act_api.h>
dc5fc579	14	#include <net/netlink.h>
1da177e4	15	#include <net/pkt_cls.h>
1da177e4	16
1da177e4 LT	17	/*
	18	* Passing parameters to the root seems to be done more awkwardly than really
	19	* necessary. At least, u32 doesn't seem to use such dirty hacks. To be
	20	* verified. FIXME.
	21	*/
	22
	23	#define PERFECT_HASH_THRESHOLD 64 /* use perfect hash if not bigger */
	24	#define DEFAULT_HASH_SIZE 64 /* optimized for diffserv */
	25
	26
1da177e4 LT	27	struct tcindex_filter_result {
	28	struct tcf_exts exts;
	29	struct tcf_result res;
	30	};
	31
	32	struct tcindex_filter {
	33	u16 key;
	34	struct tcindex_filter_result result;
	35	struct tcindex_filter *next;
	36	};
	37
	38
	39	struct tcindex_data {
	40	struct tcindex_filter_result perfect; / perfect hash; NULL if none */
	41	struct tcindex_filter *h; / imperfect hash; only used if !perfect;
	42	NULL if unused */
	43	u16 mask; /* AND key with mask */
	44	int shift; /* shift ANDed key to the right */
	45	int hash; /* hash table size; 0 if undefined */
	46	int alloc_hash; /* allocated size */
	47	int fall_through; /* 0: only classify if explicit match */
	48	};
	49
1da177e4 LT	50	static inline int
	51	tcindex_filter_is_set(struct tcindex_filter_result *r)
	52	{
	53	return tcf_exts_is_predicative(&r->exts) \|\| r->res.classid;
	54	}
	55
	56	static struct tcindex_filter_result *
	57	tcindex_lookup(struct tcindex_data *p, u16 key)
	58	{
	59	struct tcindex_filter *f;
	60
	61	if (p->perfect)
	62	return tcindex_filter_is_set(p->perfect + key) ?
	63	p->perfect + key : NULL;
	64	else if (p->h) {
	65	for (f = p->h[key % p->hash]; f; f = f->next)
	66	if (f->key == key)
	67	return &f->result;
	68	}
	69
	70	return NULL;
	71	}
	72
	73
dc7f9f6e	74	static int tcindex_classify(struct sk_buff skb, const struct tcf_proto tp,
1da177e4 LT	75	struct tcf_result *res)
1da177e4 LT	76	{
a8701a6c	77	struct tcindex_data *p = tp->root;
1da177e4 LT	78	struct tcindex_filter_result *f;
	79	int key = (skb->tc_index & p->mask) >> p->shift;
	80
aa767bfe SH	81	pr_debug("tcindex_classify(skb %p,tp %p,res %p),p %p\n",
aa767bfe SH	82	skb, tp, res, p);
1da177e4 LT	83
	84	f = tcindex_lookup(p, key);
	85	if (!f) {
	86	if (!p->fall_through)
	87	return -1;
	88	res->classid = TC_H_MAKE(TC_H_MAJ(tp->q->handle), key);
	89	res->class = 0;
aa767bfe	90	pr_debug("alg 0x%x\n", res->classid);
1da177e4 LT	91	return 0;
	92	}
	93	*res = f->res;
aa767bfe	94	pr_debug("map 0x%x\n", res->classid);
1da177e4 LT	95
	96	return tcf_exts_exec(skb, &f->exts, res);
	97	}
	98
	99
	100	static unsigned long tcindex_get(struct tcf_proto *tp, u32 handle)
	101	{
a8701a6c	102	struct tcindex_data *p = tp->root;
1da177e4 LT	103	struct tcindex_filter_result *r;
1da177e4 LT	104
aa767bfe	105	pr_debug("tcindex_get(tp %p,handle 0x%08x)\n", tp, handle);
1da177e4 LT	106	if (p->perfect && handle >= p->alloc_hash)
	107	return 0;
	108	r = tcindex_lookup(p, handle);
	109	return r && tcindex_filter_is_set(r) ? (unsigned long) r : 0UL;
	110	}
	111
	112
	113	static void tcindex_put(struct tcf_proto *tp, unsigned long f)
	114	{
aa767bfe	115	pr_debug("tcindex_put(tp %p,f 0x%lx)\n", tp, f);
1da177e4 LT	116	}
	117
	118
	119	static int tcindex_init(struct tcf_proto *tp)
	120	{
	121	struct tcindex_data *p;
	122
aa767bfe SH	123	pr_debug("tcindex_init(tp %p)\n", tp);
aa767bfe SH	124	p = kzalloc(sizeof(struct tcindex_data), GFP_KERNEL);
1da177e4 LT	125	if (!p)
	126	return -ENOMEM;
	127
1da177e4 LT	128	p->mask = 0xffff;
	129	p->hash = DEFAULT_HASH_SIZE;
	130	p->fall_through = 1;
	131
	132	tp->root = p;
	133	return 0;
	134	}
	135
	136
	137	static int
	138	__tcindex_delete(struct tcf_proto *tp, unsigned long arg, int lock)
	139	{
a8701a6c	140	struct tcindex_data *p = tp->root;
1da177e4 LT	141	struct tcindex_filter_result r = (struct tcindex_filter_result ) arg;
	142	struct tcindex_filter *f = NULL;
	143
aa767bfe	144	pr_debug("tcindex_delete(tp %p,arg 0x%lx),p %p,f %p\n", tp, arg, p, f);
1da177e4 LT	145	if (p->perfect) {
	146	if (!r->res.class)
	147	return -ENOENT;
	148	} else {
	149	int i;
	150	struct tcindex_filter **walk = NULL;
	151
	152	for (i = 0; i < p->hash; i++)
	153	for (walk = p->h+i; walk; walk = &(walk)->next)
	154	if (&(*walk)->result == r)
	155	goto found;
	156	return -ENOENT;
	157
	158	found:
	159	f = *walk;
	160	if (lock)
	161	tcf_tree_lock(tp);
	162	*walk = f->next;
	163	if (lock)
	164	tcf_tree_unlock(tp);
	165	}
	166	tcf_unbind_filter(tp, &r->res);
	167	tcf_exts_destroy(tp, &r->exts);
a51482bd	168	kfree(f);
1da177e4 LT	169	return 0;
	170	}
	171
	172	static int tcindex_delete(struct tcf_proto *tp, unsigned long arg)
	173	{
	174	return __tcindex_delete(tp, arg, 1);
	175	}
	176
	177	static inline int
	178	valid_perfect_hash(struct tcindex_data *p)
	179	{
	180	return p->hash > (p->mask >> p->shift);
	181	}
	182
6fa8c014 PM	183	static const struct nla_policy tcindex_policy[TCA_TCINDEX_MAX + 1] = {
	184	[TCA_TCINDEX_HASH] = { .type = NLA_U32 },
	185	[TCA_TCINDEX_MASK] = { .type = NLA_U16 },
	186	[TCA_TCINDEX_SHIFT] = { .type = NLA_U32 },
	187	[TCA_TCINDEX_FALL_THROUGH] = { .type = NLA_U32 },
	188	[TCA_TCINDEX_CLASSID] = { .type = NLA_U32 },
	189	};
	190
1da177e4	191	static int
c1b52739 BL	192	tcindex_set_parms(struct net net, struct tcf_proto tp, unsigned long base,
	193	u32 handle, struct tcindex_data *p,
	194	struct tcindex_filter_result r, struct nlattr *tb,
2f7ef2f8	195	struct nlattr *est, bool ovr)
1da177e4 LT	196	{
	197	int err, balloc = 0;
	198	struct tcindex_filter_result new_filter_result, *old_r = r;
	199	struct tcindex_filter_result cr;
	200	struct tcindex_data cp;
	201	struct tcindex_filter f = NULL; / make gcc behave */
	202	struct tcf_exts e;
	203
5da57f42	204	tcf_exts_init(&e, TCA_TCINDEX_ACT, TCA_TCINDEX_POLICE);
2f7ef2f8	205	err = tcf_exts_validate(net, tp, tb, est, &e, ovr);
1da177e4 LT	206	if (err < 0)
1da177e4 LT	207	return err;
10297b99	208
1da177e4 LT	209	memcpy(&cp, p, sizeof(cp));
1da177e4 LT	210	memset(&new_filter_result, 0, sizeof(new_filter_result));
5da57f42	211	tcf_exts_init(&new_filter_result.exts, TCA_TCINDEX_ACT, TCA_TCINDEX_POLICE);
1da177e4 LT	212
	213	if (old_r)
	214	memcpy(&cr, r, sizeof(cr));
33be6271	215	else {
1da177e4	216	memset(&cr, 0, sizeof(cr));
5da57f42	217	tcf_exts_init(&cr.exts, TCA_TCINDEX_ACT, TCA_TCINDEX_POLICE);
33be6271	218	}
1da177e4	219
6fa8c014	220	if (tb[TCA_TCINDEX_HASH])
1587bac4	221	cp.hash = nla_get_u32(tb[TCA_TCINDEX_HASH]);
1da177e4	222
6fa8c014	223	if (tb[TCA_TCINDEX_MASK])
1587bac4	224	cp.mask = nla_get_u16(tb[TCA_TCINDEX_MASK]);
1da177e4	225
6fa8c014	226	if (tb[TCA_TCINDEX_SHIFT])
1587bac4	227	cp.shift = nla_get_u32(tb[TCA_TCINDEX_SHIFT]);
1da177e4 LT	228
	229	err = -EBUSY;
	230	/* Hash already allocated, make sure that we still meet the
	231	* requirements for the allocated hash.
	232	*/
	233	if (cp.perfect) {
	234	if (!valid_perfect_hash(&cp) \|\|
	235	cp.hash > cp.alloc_hash)
	236	goto errout;
	237	} else if (cp.h && cp.hash != cp.alloc_hash)
	238	goto errout;
	239
	240	err = -EINVAL;
6fa8c014	241	if (tb[TCA_TCINDEX_FALL_THROUGH])
1587bac4	242	cp.fall_through = nla_get_u32(tb[TCA_TCINDEX_FALL_THROUGH]);
1da177e4 LT	243
	244	if (!cp.hash) {
	245	/* Hash not specified, use perfect hash if the upper limit
	246	* of the hashing index is below the threshold.
	247	*/
	248	if ((cp.mask >> cp.shift) < PERFECT_HASH_THRESHOLD)
cc7ec456	249	cp.hash = (cp.mask >> cp.shift) + 1;
1da177e4 LT	250	else
	251	cp.hash = DEFAULT_HASH_SIZE;
	252	}
	253
	254	if (!cp.perfect && !cp.h)
	255	cp.alloc_hash = cp.hash;
	256
	257	/* Note: this could be as restrictive as if (handle & ~(mask >> shift))
	258	* but then, we'd fail handles that may become valid after some future
	259	* mask change. While this is extremely unlikely to ever matter,
	260	* the check below is safer (and also more backwards-compatible).
	261	*/
	262	if (cp.perfect \|\| valid_perfect_hash(&cp))
	263	if (handle >= cp.alloc_hash)
	264	goto errout;
	265
	266
	267	err = -ENOMEM;
	268	if (!cp.perfect && !cp.h) {
	269	if (valid_perfect_hash(&cp)) {
0da974f4	270	cp.perfect = kcalloc(cp.hash, sizeof(*r), GFP_KERNEL);
1da177e4 LT	271	if (!cp.perfect)
1da177e4 LT	272	goto errout;
1da177e4 LT	273	balloc = 1;
1da177e4 LT	274	} else {
0da974f4	275	cp.h = kcalloc(cp.hash, sizeof(f), GFP_KERNEL);
1da177e4 LT	276	if (!cp.h)
1da177e4 LT	277	goto errout;
1da177e4 LT	278	balloc = 2;
	279	}
	280	}
	281
	282	if (cp.perfect)
	283	r = cp.perfect + handle;
	284	else
	285	r = tcindex_lookup(&cp, handle) ? : &new_filter_result;
	286
	287	if (r == &new_filter_result) {
0da974f4	288	f = kzalloc(sizeof(*f), GFP_KERNEL);
1da177e4 LT	289	if (!f)
1da177e4 LT	290	goto errout_alloc;
10297b99	291	}
1da177e4	292
add93b61	293	if (tb[TCA_TCINDEX_CLASSID]) {
1587bac4	294	cr.res.classid = nla_get_u32(tb[TCA_TCINDEX_CLASSID]);
1da177e4	295	tcf_bind_filter(tp, &cr.res, base);
10297b99	296	}
1da177e4 LT	297
	298	tcf_exts_change(tp, &cr.exts, &e);
	299
	300	tcf_tree_lock(tp);
	301	if (old_r && old_r != r)
	302	memset(old_r, 0, sizeof(*old_r));
	303
	304	memcpy(p, &cp, sizeof(cp));
	305	memcpy(r, &cr, sizeof(cr));
	306
	307	if (r == &new_filter_result) {
	308	struct tcindex_filter **fp;
	309
	310	f->key = handle;
	311	f->result = new_filter_result;
	312	f->next = NULL;
	313	for (fp = p->h+(handle % p->hash); fp; fp = &(fp)->next)
	314	/* nothing */;
	315	*fp = f;
10297b99	316	}
1da177e4 LT	317	tcf_tree_unlock(tp);
	318
	319	return 0;
	320
	321	errout_alloc:
	322	if (balloc == 1)
	323	kfree(cp.perfect);
	324	else if (balloc == 2)
	325	kfree(cp.h);
	326	errout:
	327	tcf_exts_destroy(tp, &e);
	328	return err;
	329	}
	330
	331	static int
c1b52739	332	tcindex_change(struct net net, struct sk_buff in_skb,
af4c6641	333	struct tcf_proto *tp, unsigned long base, u32 handle,
2f7ef2f8	334	struct nlattr *tca, unsigned long arg, bool ovr)
1da177e4	335	{
add93b61 PM	336	struct nlattr *opt = tca[TCA_OPTIONS];
add93b61 PM	337	struct nlattr *tb[TCA_TCINDEX_MAX + 1];
a8701a6c	338	struct tcindex_data *p = tp->root;
1da177e4	339	struct tcindex_filter_result r = (struct tcindex_filter_result ) *arg;
cee63723	340	int err;
1da177e4	341
aa767bfe	342	pr_debug("tcindex_change(tp %p,handle 0x%08x,tca %p,arg %p),opt %p,"
1da177e4 LT	343	"p %p,r %p,*arg 0x%lx\n",
	344	tp, handle, tca, arg, opt, p, r, arg ? *arg : 0L);
	345
	346	if (!opt)
	347	return 0;
	348
6fa8c014	349	err = nla_parse_nested(tb, TCA_TCINDEX_MAX, opt, tcindex_policy);
cee63723 PM	350	if (err < 0)
cee63723 PM	351	return err;
1da177e4	352
c1b52739	353	return tcindex_set_parms(net, tp, base, handle, p, r, tb,
2f7ef2f8	354	tca[TCA_RATE], ovr);
1da177e4 LT	355	}
	356
	357
	358	static void tcindex_walk(struct tcf_proto tp, struct tcf_walker walker)
	359	{
a8701a6c	360	struct tcindex_data *p = tp->root;
aa767bfe	361	struct tcindex_filter f, next;
1da177e4 LT	362	int i;
1da177e4 LT	363
aa767bfe	364	pr_debug("tcindex_walk(tp %p,walker %p),p %p\n", tp, walker, p);
1da177e4 LT	365	if (p->perfect) {
	366	for (i = 0; i < p->hash; i++) {
	367	if (!p->perfect[i].res.class)
	368	continue;
	369	if (walker->count >= walker->skip) {
	370	if (walker->fn(tp,
	371	(unsigned long) (p->perfect+i), walker)
	372	< 0) {
	373	walker->stop = 1;
	374	return;
	375	}
	376	}
	377	walker->count++;
	378	}
	379	}
	380	if (!p->h)
	381	return;
	382	for (i = 0; i < p->hash; i++) {
	383	for (f = p->h[i]; f; f = next) {
	384	next = f->next;
	385	if (walker->count >= walker->skip) {
aa767bfe	386	if (walker->fn(tp, (unsigned long) &f->result,
1da177e4 LT	387	walker) < 0) {
	388	walker->stop = 1;
	389	return;
	390	}
	391	}
	392	walker->count++;
	393	}
	394	}
	395	}
	396
	397
	398	static int tcindex_destroy_element(struct tcf_proto *tp,
	399	unsigned long arg, struct tcf_walker *walker)
	400	{
	401	return __tcindex_delete(tp, arg, 0);
	402	}
	403
	404
	405	static void tcindex_destroy(struct tcf_proto *tp)
	406	{
a8701a6c	407	struct tcindex_data *p = tp->root;
1da177e4 LT	408	struct tcf_walker walker;
1da177e4 LT	409
aa767bfe	410	pr_debug("tcindex_destroy(tp %p),p %p\n", tp, p);
1da177e4 LT	411	walker.count = 0;
	412	walker.skip = 0;
	413	walker.fn = &tcindex_destroy_element;
aa767bfe	414	tcindex_walk(tp, &walker);
a51482bd JJ	415	kfree(p->perfect);
a51482bd JJ	416	kfree(p->h);
1da177e4 LT	417	kfree(p);
	418	tp->root = NULL;
	419	}
	420
	421
832d1d5b	422	static int tcindex_dump(struct net net, struct tcf_proto tp, unsigned long fh,
1da177e4 LT	423	struct sk_buff skb, struct tcmsg t)
1da177e4 LT	424	{
a8701a6c	425	struct tcindex_data *p = tp->root;
1da177e4	426	struct tcindex_filter_result r = (struct tcindex_filter_result ) fh;
27a884dc	427	unsigned char *b = skb_tail_pointer(skb);
4b3550ef	428	struct nlattr *nest;
1da177e4	429
aa767bfe SH	430	pr_debug("tcindex_dump(tp %p,fh 0x%lx,skb %p,t %p),p %p,r %p,b %p\n",
	431	tp, fh, skb, t, p, r, b);
	432	pr_debug("p->perfect %p p->h %p\n", p->perfect, p->h);
4b3550ef PM	433
	434	nest = nla_nest_start(skb, TCA_OPTIONS);
	435	if (nest == NULL)
	436	goto nla_put_failure;
	437
1da177e4 LT	438	if (!fh) {
1da177e4 LT	439	t->tcm_handle = ~0; /* whatever ... */
1b34ec43 DM	440	if (nla_put_u32(skb, TCA_TCINDEX_HASH, p->hash) \|\|
	441	nla_put_u16(skb, TCA_TCINDEX_MASK, p->mask) \|\|
	442	nla_put_u32(skb, TCA_TCINDEX_SHIFT, p->shift) \|\|
	443	nla_put_u32(skb, TCA_TCINDEX_FALL_THROUGH, p->fall_through))
	444	goto nla_put_failure;
4b3550ef	445	nla_nest_end(skb, nest);
1da177e4 LT	446	} else {
	447	if (p->perfect) {
	448	t->tcm_handle = r-p->perfect;
	449	} else {
	450	struct tcindex_filter *f;
	451	int i;
	452
	453	t->tcm_handle = 0;
	454	for (i = 0; !t->tcm_handle && i < p->hash; i++) {
	455	for (f = p->h[i]; !t->tcm_handle && f;
	456	f = f->next) {
	457	if (&f->result == r)
	458	t->tcm_handle = f->key;
	459	}
	460	}
	461	}
aa767bfe	462	pr_debug("handle = %d\n", t->tcm_handle);
1b34ec43 DM	463	if (r->res.class &&
	464	nla_put_u32(skb, TCA_TCINDEX_CLASSID, r->res.classid))
	465	goto nla_put_failure;
1da177e4	466
5da57f42	467	if (tcf_exts_dump(skb, &r->exts) < 0)
add93b61	468	goto nla_put_failure;
4b3550ef	469	nla_nest_end(skb, nest);
1da177e4	470
5da57f42	471	if (tcf_exts_dump_stats(skb, &r->exts) < 0)
add93b61	472	goto nla_put_failure;
1da177e4	473	}
10297b99	474
1da177e4 LT	475	return skb->len;
1da177e4 LT	476
add93b61	477	nla_put_failure:
dc5fc579	478	nlmsg_trim(skb, b);
1da177e4 LT	479	return -1;
	480	}
	481
2eb9d75c	482	static struct tcf_proto_ops cls_tcindex_ops __read_mostly = {
1da177e4 LT	483	.kind = "tcindex",
	484	.classify = tcindex_classify,
	485	.init = tcindex_init,
	486	.destroy = tcindex_destroy,
	487	.get = tcindex_get,
	488	.put = tcindex_put,
	489	.change = tcindex_change,
	490	.delete = tcindex_delete,
	491	.walk = tcindex_walk,
	492	.dump = tcindex_dump,
	493	.owner = THIS_MODULE,
	494	};
	495
	496	static int __init init_tcindex(void)
	497	{
	498	return register_tcf_proto_ops(&cls_tcindex_ops);
	499	}
	500
10297b99	501	static void __exit exit_tcindex(void)
1da177e4 LT	502	{
	503	unregister_tcf_proto_ops(&cls_tcindex_ops);
	504	}
	505
	506	module_init(init_tcindex)
	507	module_exit(exit_tcindex)
	508	MODULE_LICENSE("GPL");