4 files changed, 270 insertions, 0 deletions

diff --git a/include/uapi/linux/pkt_cls.h b/include/uapi/linux/pkt_cls.h
index 5702e933dc07..a32494887e01 100644
--- a/include/uapi/linux/pkt_cls.h
+++ b/include/uapi/linux/pkt_cls.h
@@ -433,6 +433,17 @@ enum {
 
 #define TCA_FLOWER_MAX (__TCA_FLOWER_MAX - 1)
 
+/* Match-all classifier */
+
+enum {
+	TCA_MATCHALL_UNSPEC,
+	TCA_MATCHALL_CLASSID,
+	TCA_MATCHALL_ACT,
+	__TCA_MATCHALL_MAX,
+};
+
+#define TCA_MATCHALL_MAX (__TCA_MATCHALL_MAX - 1)
+
 /* Extended Matches */
 
 struct tcf_ematch_tree_hdr {
diff --git a/net/sched/Kconfig b/net/sched/Kconfig
index b148302bbaf2..ccf931b3b94c 100644
--- a/net/sched/Kconfig
+++ b/net/sched/Kconfig
@@ -494,6 +494,16 @@ config NET_CLS_FLOWER
 	  To compile this code as a module, choose M here: the module will
 	  be called cls_flower.
 
+config NET_CLS_MATCHALL
+	tristate "Match-all classifier"
+	select NET_CLS
+	---help---
+	  If you say Y here, you will be able to classify packets based on
+	  nothing. Every packet will match.
+
+	  To compile this code as a module, choose M here: the module will
+	  be called cls_matchall.
+
 config NET_EMATCH
 	bool "Extended Matches"
 	select NET_CLS
diff --git a/net/sched/Makefile b/net/sched/Makefile
index 84bddb373517..ae088a5a9d95 100644
--- a/net/sched/Makefile
+++ b/net/sched/Makefile
@@ -60,6 +60,7 @@ obj-$(CONFIG_NET_CLS_FLOW)	+= cls_flow.o
 obj-$(CONFIG_NET_CLS_CGROUP)	+= cls_cgroup.o
 obj-$(CONFIG_NET_CLS_BPF)	+= cls_bpf.o
 obj-$(CONFIG_NET_CLS_FLOWER)	+= cls_flower.o
+obj-$(CONFIG_NET_CLS_MATCHALL)	+= cls_matchall.o
 obj-$(CONFIG_NET_EMATCH)	+= ematch.o
 obj-$(CONFIG_NET_EMATCH_CMP)	+= em_cmp.o
 obj-$(CONFIG_NET_EMATCH_NBYTE)	+= em_nbyte.o
diff --git a/net/sched/cls_matchall.c b/net/sched/cls_matchall.c
new file mode 100644
index 000000000000..8a6b4de7a99a
--- /dev/null
+++ b/net/sched/cls_matchall.c
@@ -0,0 +1,248 @@
+/*
+ * net/sched/cls_matchll.c		Match-all classifier
+ *
+ * Copyright (c) 2016 Jiri Pirko <jiri@mellanox.com>
+ *
+ * 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.
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/module.h>
+
+#include <net/sch_generic.h>
+#include <net/pkt_cls.h>
+
+struct cls_mall_filter {
+	struct tcf_exts exts;
+	struct tcf_result res;
+	u32 handle;
+	struct rcu_head	rcu;
+};
+
+struct cls_mall_head {
+	struct cls_mall_filter *filter;
+	struct rcu_head	rcu;
+};
+
+static int mall_classify(struct sk_buff *skb, const struct tcf_proto *tp,
+			 struct tcf_result *res)
+{
+	struct cls_mall_head *head = rcu_dereference_bh(tp->root);
+	struct cls_mall_filter *f = head->filter;
+
+	return tcf_exts_exec(skb, &f->exts, res);
+}
+
+static int mall_init(struct tcf_proto *tp)
+{
+	struct cls_mall_head *head;
+
+	head = kzalloc(sizeof(*head), GFP_KERNEL);
+	if (!head)
+		return -ENOBUFS;
+
+	rcu_assign_pointer(tp->root, head);
+
+	return 0;
+}
+
+static void mall_destroy_filter(struct rcu_head *head)
+{
+	struct cls_mall_filter *f = container_of(head, struct cls_mall_filter, rcu);
+
+	tcf_exts_destroy(&f->exts);
+	kfree(f);
+}
+
+static bool mall_destroy(struct tcf_proto *tp, bool force)
+{
+	struct cls_mall_head *head = rtnl_dereference(tp->root);
+
+	if (!force && head->filter)
+		return false;
+
+	if (head->filter)
+		call_rcu(&head->filter->rcu, mall_destroy_filter);
+	RCU_INIT_POINTER(tp->root, NULL);
+	kfree_rcu(head, rcu);
+	return true;
+}
+
+static unsigned long mall_get(struct tcf_proto *tp, u32 handle)
+{
+	struct cls_mall_head *head = rtnl_dereference(tp->root);
+	struct cls_mall_filter *f = head->filter;
+
+	if (f && f->handle == handle)
+		return (unsigned long) f;
+	return 0;
+}
+
+static const struct nla_policy mall_policy[TCA_MATCHALL_MAX + 1] = {
+	[TCA_MATCHALL_UNSPEC]		= { .type = NLA_UNSPEC },
+	[TCA_MATCHALL_CLASSID]		= { .type = NLA_U32 },
+};
+
+static int mall_set_parms(struct net *net, struct tcf_proto *tp,
+			  struct cls_mall_filter *f,
+			  unsigned long base, struct nlattr **tb,
+			  struct nlattr *est, bool ovr)
+{
+	struct tcf_exts e;
+	int err;
+
+	tcf_exts_init(&e, TCA_MATCHALL_ACT, 0);
+	err = tcf_exts_validate(net, tp, tb, est, &e, ovr);
+	if (err < 0)
+		return err;
+
+	if (tb[TCA_MATCHALL_CLASSID]) {
+		f->res.classid = nla_get_u32(tb[TCA_MATCHALL_CLASSID]);
+		tcf_bind_filter(tp, &f->res, base);
+	}
+
+	tcf_exts_change(tp, &f->exts, &e);
+
+	return 0;
+}
+
+static int mall_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 cls_mall_head *head = rtnl_dereference(tp->root);
+	struct cls_mall_filter *fold = (struct cls_mall_filter *) *arg;
+	struct cls_mall_filter *f;
+	struct nlattr *tb[TCA_MATCHALL_MAX + 1];
+	int err;
+
+	if (!tca[TCA_OPTIONS])
+		return -EINVAL;
+
+	if (head->filter)
+		return -EBUSY;
+
+	if (fold)
+		return -EINVAL;
+
+	err = nla_parse_nested(tb, TCA_MATCHALL_MAX,
+			       tca[TCA_OPTIONS], mall_policy);
+	if (err < 0)
+		return err;
+
+	f = kzalloc(sizeof(*f), GFP_KERNEL);
+	if (!f)
+		return -ENOBUFS;
+
+	tcf_exts_init(&f->exts, TCA_MATCHALL_ACT, 0);
+
+	if (!handle)
+		handle = 1;
+	f->handle = handle;
+
+	err = mall_set_parms(net, tp, f, base, tb, tca[TCA_RATE], ovr);
+	if (err)
+		goto errout;
+
+	*arg = (unsigned long) f;
+	rcu_assign_pointer(head->filter, f);
+
+	return 0;
+
+errout:
+	kfree(f);
+	return err;
+}
+
+static int mall_delete(struct tcf_proto *tp, unsigned long arg)
+{
+	struct cls_mall_head *head = rtnl_dereference(tp->root);
+	struct cls_mall_filter *f = (struct cls_mall_filter *) arg;
+
+	RCU_INIT_POINTER(head->filter, NULL);
+	tcf_unbind_filter(tp, &f->res);
+	call_rcu(&f->rcu, mall_destroy_filter);
+	return 0;
+}
+
+static void mall_walk(struct tcf_proto *tp, struct tcf_walker *arg)
+{
+	struct cls_mall_head *head = rtnl_dereference(tp->root);
+	struct cls_mall_filter *f = head->filter;
+
+	if (arg->count < arg->skip)
+		goto skip;
+	if (arg->fn(tp, (unsigned long) f, arg) < 0)
+		arg->stop = 1;
+skip:
+	arg->count++;
+}
+
+static int mall_dump(struct net *net, struct tcf_proto *tp, unsigned long fh,
+		     struct sk_buff *skb, struct tcmsg *t)
+{
+	struct cls_mall_filter *f = (struct cls_mall_filter *) fh;
+	struct nlattr *nest;
+
+	if (!f)
+		return skb->len;
+
+	t->tcm_handle = f->handle;
+
+	nest = nla_nest_start(skb, TCA_OPTIONS);
+	if (!nest)
+		goto nla_put_failure;
+
+	if (f->res.classid &&
+	    nla_put_u32(skb, TCA_MATCHALL_CLASSID, f->res.classid))
+		goto nla_put_failure;
+
+	if (tcf_exts_dump(skb, &f->exts))
+		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_mall_ops __read_mostly = {
+	.kind		= "matchall",
+	.classify	= mall_classify,
+	.init		= mall_init,
+	.destroy	= mall_destroy,
+	.get		= mall_get,
+	.change		= mall_change,
+	.delete		= mall_delete,
+	.walk		= mall_walk,
+	.dump		= mall_dump,
+	.owner		= THIS_MODULE,
+};
+
+static int __init cls_mall_init(void)
+{
+	return register_tcf_proto_ops(&cls_mall_ops);
+}
+
+static void __exit cls_mall_exit(void)
+{
+	unregister_tcf_proto_ops(&cls_mall_ops);
+}
+
+module_init(cls_mall_init);
+module_exit(cls_mall_exit);
+
+MODULE_AUTHOR("Jiri Pirko <jiri@mellanox.com>");
+MODULE_DESCRIPTION("Match-all classifier");
+MODULE_LICENSE("GPL v2");