netfilter: nf_tables: Add meta expression key for bridge interface name

NFT_META_BRI_IIFNAME to get packet input bridge interface name NFT_META_BRI_OIFNAME to get packet output bridge interface name Such meta key are accessible only through NFPROTO_BRIDGE family, on a dedicated nft meta module: nft_meta_bridge. Suggested-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: nf_tables: Add meta expression key for bridge interface name
NFT_META_BRI_IIFNAME to get packet input bridge interface name NFT_META_BRI_OIFNAME to get packet output bridge interface name Such meta key are accessible only through NFPROTO_BRIDGE family, on a dedicated nft meta module: nft_meta_bridge. Suggested-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Tomasz Bursztyka · Pablo Neira Ayuso
1 parent aa45660c6b
Showing 5 changed files with 158 additions and 2 deletions Side-by-side Diff
include/uapi/linux/netfilter/nf_tables.h
net/bridge/Makefile
net/bridge/netfilter/Kconfig
net/bridge/netfilter/Makefile
net/bridge/netfilter/nft_meta_bridge.c
@@ -563,6 +563,8 @@
  * @NFT_META_SECMARK: packet secmark (skb->secmark)
  * @NFT_META_NFPROTO: netfilter protocol
  * @NFT_META_L4PROTO: layer 4 protocol number
+ * @NFT_META_BRI_IIFNAME: packet input bridge interface name
+ * @NFT_META_BRI_OIFNAME: packet output bridge interface name
  */
 enum nft_meta_keys {
 	NFT_META_LEN,
@@ -582,6 +584,8 @@
 	NFT_META_SECMARK,
 	NFT_META_NFPROTO,
 	NFT_META_L4PROTO,
+	NFT_META_BRI_IIFNAME,
+	NFT_META_BRI_OIFNAME,
 };
  
 /**
@@ -16,5 +16,5 @@
  
 bridge-$(CONFIG_BRIDGE_VLAN_FILTERING) += br_vlan.o
  
-obj-$(CONFIG_BRIDGE_NF_EBTABLES) += netfilter/
+obj-$(CONFIG_BRIDGE_NETFILTER) += netfilter/
@@ -2,13 +2,25 @@
 # Bridge netfilter configuration
 #
 #
-config NF_TABLES_BRIDGE
+menuconfig NF_TABLES_BRIDGE
 	depends on NF_TABLES
+	select BRIDGE_NETFILTER
 	tristate "Ethernet Bridge nf_tables support"
  
+if NF_TABLES_BRIDGE
+
+config NFT_BRIDGE_META
+	tristate "Netfilter nf_table bridge meta support"
+	depends on NFT_META
+	help
+	  Add support for bridge dedicated meta key.
+
+endif # NF_TABLES_BRIDGE
+
 menuconfig BRIDGE_NF_EBTABLES
 	tristate "Ethernet Bridge tables (ebtables) support"
 	depends on BRIDGE && NETFILTER
+	select BRIDGE_NETFILTER
 	select NETFILTER_XTABLES
 	help
 	  ebtables is a general, extensible frame/packet identification
@@ -3,6 +3,7 @@
 #
  
 obj-$(CONFIG_NF_TABLES_BRIDGE) += nf_tables_bridge.o
+obj-$(CONFIG_NFT_BRIDGE_META)  += nft_meta_bridge.o
  
 obj-$(CONFIG_BRIDGE_NF_EBTABLES) += ebtables.o
  
+/*
+ * Copyright (c) 2014 Intel Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/netlink.h>
+#include <linux/netfilter.h>
+#include <linux/netfilter/nf_tables.h>
+#include <net/netfilter/nf_tables.h>
+#include <net/netfilter/nft_meta.h>
+
+#include "../br_private.h"
+
+static void nft_meta_bridge_get_eval(const struct nft_expr *expr,
+				     struct nft_data data[NFT_REG_MAX + 1],
+				     const struct nft_pktinfo *pkt)
+{
+	const struct nft_meta *priv = nft_expr_priv(expr);
+	const struct net_device *in = pkt->in, *out = pkt->out;
+	struct nft_data *dest = &data[priv->dreg];
+	const struct net_bridge_port *p;
+
+	switch (priv->key) {
+	case NFT_META_BRI_IIFNAME:
+		if (in == NULL || (p = br_port_get_rcu(in)) == NULL)
+			goto err;
+		break;
+	case NFT_META_BRI_OIFNAME:
+		if (out == NULL || (p = br_port_get_rcu(out)) == NULL)
+			goto err;
+		break;
+	default:
+		goto out;
+	}
+
+	strncpy((char *)dest->data, p->br->dev->name, sizeof(dest->data));
+	return;
+out:
+	return nft_meta_get_eval(expr, data, pkt);
+err:
+	data[NFT_REG_VERDICT].verdict = NFT_BREAK;
+}
+
+static int nft_meta_bridge_get_init(const struct nft_ctx *ctx,
+				    const struct nft_expr *expr,
+				    const struct nlattr * const tb[])
+{
+	struct nft_meta *priv = nft_expr_priv(expr);
+	int err;
+
+	priv->key = ntohl(nla_get_be32(tb[NFTA_META_KEY]));
+	switch (priv->key) {
+	case NFT_META_BRI_IIFNAME:
+	case NFT_META_BRI_OIFNAME:
+		break;
+	default:
+		return nft_meta_get_init(ctx, expr, tb);
+	}
+
+	priv->dreg = ntohl(nla_get_be32(tb[NFTA_META_DREG]));
+	err = nft_validate_output_register(priv->dreg);
+	if (err < 0)
+		return err;
+
+	err = nft_validate_data_load(ctx, priv->dreg, NULL, NFT_DATA_VALUE);
+	if (err < 0)
+		return err;
+
+	return 0;
+}
+
+static struct nft_expr_type nft_meta_bridge_type;
+static const struct nft_expr_ops nft_meta_bridge_get_ops = {
+	.type		= &nft_meta_bridge_type,
+	.size		= NFT_EXPR_SIZE(sizeof(struct nft_meta)),
+	.eval		= nft_meta_bridge_get_eval,
+	.init		= nft_meta_bridge_get_init,
+	.dump		= nft_meta_get_dump,
+};
+
+static const struct nft_expr_ops nft_meta_bridge_set_ops = {
+	.type		= &nft_meta_bridge_type,
+	.size		= NFT_EXPR_SIZE(sizeof(struct nft_meta)),
+	.eval		= nft_meta_set_eval,
+	.init		= nft_meta_set_init,
+	.dump		= nft_meta_set_dump,
+};
+
+static const struct nft_expr_ops *
+nft_meta_bridge_select_ops(const struct nft_ctx *ctx,
+			   const struct nlattr * const tb[])
+{
+	if (tb[NFTA_META_KEY] == NULL)
+		return ERR_PTR(-EINVAL);
+
+	if (tb[NFTA_META_DREG] && tb[NFTA_META_SREG])
+		return ERR_PTR(-EINVAL);
+
+	if (tb[NFTA_META_DREG])
+		return &nft_meta_bridge_get_ops;
+
+	if (tb[NFTA_META_SREG])
+		return &nft_meta_bridge_set_ops;
+
+	return ERR_PTR(-EINVAL);
+}
+
+static struct nft_expr_type nft_meta_bridge_type __read_mostly = {
+	.family         = NFPROTO_BRIDGE,
+	.name           = "meta",
+	.select_ops     = &nft_meta_bridge_select_ops,
+	.policy         = nft_meta_policy,
+	.maxattr        = NFTA_META_MAX,
+	.owner          = THIS_MODULE,
+};
+
+static int __init nft_meta_bridge_module_init(void)
+{
+	return nft_register_expr(&nft_meta_bridge_type);
+}
+
+static void __exit nft_meta_bridge_module_exit(void)
+{
+	nft_unregister_expr(&nft_meta_bridge_type);
+}
+
+module_init(nft_meta_bridge_module_init);
+module_exit(nft_meta_bridge_module_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>");
+MODULE_ALIAS_NFT_AF_EXPR(AF_BRIDGE, "meta");
...	...	@@ -563,6 +563,8 @@
563	563	* @NFT_META_SECMARK: packet secmark (skb->secmark)
564	564	* @NFT_META_NFPROTO: netfilter protocol
565	565	* @NFT_META_L4PROTO: layer 4 protocol number
	566	+ * @NFT_META_BRI_IIFNAME: packet input bridge interface name
	567	+ * @NFT_META_BRI_OIFNAME: packet output bridge interface name
566	568	*/
567	569	enum nft_meta_keys {
568	570	NFT_META_LEN,
...	...	@@ -582,6 +584,8 @@
582	584	NFT_META_SECMARK,
583	585	NFT_META_NFPROTO,
584	586	NFT_META_L4PROTO,
	587	+ NFT_META_BRI_IIFNAME,
	588	+ NFT_META_BRI_OIFNAME,
585	589	};
586	590
587	591	/**
...	...	@@ -16,5 +16,5 @@
16	16
17	17	bridge-$(CONFIG_BRIDGE_VLAN_FILTERING) += br_vlan.o
18	18
19		-obj-$(CONFIG_BRIDGE_NF_EBTABLES) += netfilter/
	19	+obj-$(CONFIG_BRIDGE_NETFILTER) += netfilter/
...	...	@@ -2,13 +2,25 @@
2	2	# Bridge netfilter configuration
3	3	#
4	4	#
5		-config NF_TABLES_BRIDGE
	5	+menuconfig NF_TABLES_BRIDGE
6	6	depends on NF_TABLES
	7	+ select BRIDGE_NETFILTER
7	8	tristate "Ethernet Bridge nf_tables support"
8	9
	10	+if NF_TABLES_BRIDGE
	11	+
	12	+config NFT_BRIDGE_META
	13	+ tristate "Netfilter nf_table bridge meta support"
	14	+ depends on NFT_META
	15	+ help
	16	+ Add support for bridge dedicated meta key.
	17	+
	18	+endif # NF_TABLES_BRIDGE
	19	+
9	20	menuconfig BRIDGE_NF_EBTABLES
10	21	tristate "Ethernet Bridge tables (ebtables) support"
11	22	depends on BRIDGE && NETFILTER
	23	+ select BRIDGE_NETFILTER
12	24	select NETFILTER_XTABLES
13	25	help
14	26	ebtables is a general, extensible frame/packet identification
...	...	@@ -3,6 +3,7 @@
3	3	#
4	4
5	5	obj-$(CONFIG_NF_TABLES_BRIDGE) += nf_tables_bridge.o
	6	+obj-$(CONFIG_NFT_BRIDGE_META) += nft_meta_bridge.o
6	7
7	8	obj-$(CONFIG_BRIDGE_NF_EBTABLES) += ebtables.o
8	9
	1	+/*
	2	+ * Copyright (c) 2014 Intel Corporation
	3	+ *
	4	+ * This program is free software; you can redistribute it and/or modify
	5	+ * it under the terms of the GNU General Public License version 2 as
	6	+ * published by the Free Software Foundation.
	7	+ *
	8	+ */
	9	+
	10	+#include <linux/kernel.h>
	11	+#include <linux/init.h>
	12	+#include <linux/module.h>
	13	+#include <linux/netlink.h>
	14	+#include <linux/netfilter.h>
	15	+#include <linux/netfilter/nf_tables.h>
	16	+#include <net/netfilter/nf_tables.h>
	17	+#include <net/netfilter/nft_meta.h>
	18	+
	19	+#include "../br_private.h"
	20	+
	21	+static void nft_meta_bridge_get_eval(const struct nft_expr *expr,
	22	+ struct nft_data data[NFT_REG_MAX + 1],
	23	+ const struct nft_pktinfo *pkt)
	24	+{
	25	+ const struct nft_meta *priv = nft_expr_priv(expr);
	26	+ const struct net_device in = pkt->in, out = pkt->out;
	27	+ struct nft_data *dest = &data[priv->dreg];
	28	+ const struct net_bridge_port *p;
	29	+
	30	+ switch (priv->key) {
	31	+ case NFT_META_BRI_IIFNAME:
	32	+ if (in == NULL \|\| (p = br_port_get_rcu(in)) == NULL)
	33	+ goto err;
	34	+ break;
	35	+ case NFT_META_BRI_OIFNAME:
	36	+ if (out == NULL \|\| (p = br_port_get_rcu(out)) == NULL)
	37	+ goto err;
	38	+ break;
	39	+ default:
	40	+ goto out;
	41	+ }
	42	+
	43	+ strncpy((char *)dest->data, p->br->dev->name, sizeof(dest->data));
	44	+ return;
	45	+out:
	46	+ return nft_meta_get_eval(expr, data, pkt);
	47	+err:
	48	+ data[NFT_REG_VERDICT].verdict = NFT_BREAK;
	49	+}
	50	+
	51	+static int nft_meta_bridge_get_init(const struct nft_ctx *ctx,
	52	+ const struct nft_expr *expr,
	53	+ const struct nlattr * const tb[])
	54	+{
	55	+ struct nft_meta *priv = nft_expr_priv(expr);
	56	+ int err;
	57	+
	58	+ priv->key = ntohl(nla_get_be32(tb[NFTA_META_KEY]));
	59	+ switch (priv->key) {
	60	+ case NFT_META_BRI_IIFNAME:
	61	+ case NFT_META_BRI_OIFNAME:
	62	+ break;
	63	+ default:
	64	+ return nft_meta_get_init(ctx, expr, tb);
	65	+ }
	66	+
	67	+ priv->dreg = ntohl(nla_get_be32(tb[NFTA_META_DREG]));
	68	+ err = nft_validate_output_register(priv->dreg);
	69	+ if (err < 0)
	70	+ return err;
	71	+
	72	+ err = nft_validate_data_load(ctx, priv->dreg, NULL, NFT_DATA_VALUE);
	73	+ if (err < 0)
	74	+ return err;
	75	+
	76	+ return 0;
	77	+}
	78	+
	79	+static struct nft_expr_type nft_meta_bridge_type;
	80	+static const struct nft_expr_ops nft_meta_bridge_get_ops = {
	81	+ .type = &nft_meta_bridge_type,
	82	+ .size = NFT_EXPR_SIZE(sizeof(struct nft_meta)),
	83	+ .eval = nft_meta_bridge_get_eval,
	84	+ .init = nft_meta_bridge_get_init,
	85	+ .dump = nft_meta_get_dump,
	86	+};
	87	+
	88	+static const struct nft_expr_ops nft_meta_bridge_set_ops = {
	89	+ .type = &nft_meta_bridge_type,
	90	+ .size = NFT_EXPR_SIZE(sizeof(struct nft_meta)),
	91	+ .eval = nft_meta_set_eval,
	92	+ .init = nft_meta_set_init,
	93	+ .dump = nft_meta_set_dump,
	94	+};
	95	+
	96	+static const struct nft_expr_ops *
	97	+nft_meta_bridge_select_ops(const struct nft_ctx *ctx,
	98	+ const struct nlattr * const tb[])
	99	+{
	100	+ if (tb[NFTA_META_KEY] == NULL)
	101	+ return ERR_PTR(-EINVAL);
	102	+
	103	+ if (tb[NFTA_META_DREG] && tb[NFTA_META_SREG])
	104	+ return ERR_PTR(-EINVAL);
	105	+
	106	+ if (tb[NFTA_META_DREG])
	107	+ return &nft_meta_bridge_get_ops;
	108	+
	109	+ if (tb[NFTA_META_SREG])
	110	+ return &nft_meta_bridge_set_ops;
	111	+
	112	+ return ERR_PTR(-EINVAL);
	113	+}
	114	+
	115	+static struct nft_expr_type nft_meta_bridge_type __read_mostly = {
	116	+ .family = NFPROTO_BRIDGE,
	117	+ .name = "meta",
	118	+ .select_ops = &nft_meta_bridge_select_ops,
	119	+ .policy = nft_meta_policy,
	120	+ .maxattr = NFTA_META_MAX,
	121	+ .owner = THIS_MODULE,
	122	+};
	123	+
	124	+static int __init nft_meta_bridge_module_init(void)
	125	+{
	126	+ return nft_register_expr(&nft_meta_bridge_type);
	127	+}
	128	+
	129	+static void __exit nft_meta_bridge_module_exit(void)
	130	+{
	131	+ nft_unregister_expr(&nft_meta_bridge_type);
	132	+}
	133	+
	134	+module_init(nft_meta_bridge_module_init);
	135	+module_exit(nft_meta_bridge_module_exit);
	136	+
	137	+MODULE_LICENSE("GPL");
	138	+MODULE_AUTHOR("Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>");
	139	+MODULE_ALIAS_NFT_AF_EXPR(AF_BRIDGE, "meta");