Initial import

1 files changed, 674 insertions, 0 deletions

diff --git a/net/sched/cls_route.c b/net/sched/cls_route.c
new file mode 100644
index 000000000..08a3b0a6f
--- /dev/null
+++ b/net/sched/cls_route.c
@@ -0,0 +1,674 @@
+/*
+ * 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)
+{
+	int err;
+	u32 id = 0, to = 0, nhandle = 0x8000;
+	struct route4_filter *fp;
+	unsigned int h1;
+	struct route4_bucket *b;
+	struct tcf_exts e;
+
+	tcf_exts_init(&e, TCA_ROUTE4_ACT, TCA_ROUTE4_POLICE);
+	err = tcf_exts_validate(net, tp, tb, est, &e, ovr);
+	if (err < 0)
+		return err;
+
+	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;
+
+	tcf_exts_init(&f->exts, TCA_ROUTE4_ACT, TCA_ROUTE4_POLICE);
+	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:
+	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");