netfilter: ipt_addrtype: rename to xt_addrtype

Followup patch will add ipv6 support.

ipt_addrtype.h is retained for compatibility reasons, but no longer used
by the kernel.

Signed-off-by: Florian Westphal <fwestphal@astaro.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>

3 files changed, 146 insertions, 0 deletions

diff --git a/net/netfilter/Kconfig b/net/netfilter/Kconfig
index 82a6e0d80f0..32bff6d86cb 100644
--- a/net/netfilter/Kconfig
+++ b/net/netfilter/Kconfig
@@ -649,6 +649,16 @@ config NETFILTER_XT_TARGET_TCPOPTSTRIP
 
 comment "Xtables matches"
 
+config NETFILTER_XT_MATCH_ADDRTYPE
+	tristate '"addrtype" address type match support'
+	depends on NETFILTER_ADVANCED
+	---help---
+	  This option allows you to match what routing thinks of an address,
+	  eg. UNICAST, LOCAL, BROADCAST, ...
+
+	  If you want to compile it as a module, say M here and read
+	  <file:Documentation/kbuild/modules.txt>.  If unsure, say `N'.
+
 config NETFILTER_XT_MATCH_CLUSTER
 	tristate '"cluster" match support'
 	depends on NF_CONNTRACK
diff --git a/net/netfilter/Makefile b/net/netfilter/Makefile
index d57a890eaee..1a02853df86 100644
--- a/net/netfilter/Makefile
+++ b/net/netfilter/Makefile
@@ -70,6 +70,7 @@ obj-$(CONFIG_NETFILTER_XT_TARGET_TRACE) += xt_TRACE.o
 obj-$(CONFIG_NETFILTER_XT_TARGET_IDLETIMER) += xt_IDLETIMER.o
 
 # matches
+obj-$(CONFIG_NETFILTER_XT_MATCH_ADDRTYPE) += xt_addrtype.o
 obj-$(CONFIG_NETFILTER_XT_MATCH_CLUSTER) += xt_cluster.o
 obj-$(CONFIG_NETFILTER_XT_MATCH_COMMENT) += xt_comment.o
 obj-$(CONFIG_NETFILTER_XT_MATCH_CONNBYTES) += xt_connbytes.o
diff --git a/net/netfilter/xt_addrtype.c b/net/netfilter/xt_addrtype.c
new file mode 100644
index 00000000000..e89c0b84583
--- /dev/null
+++ b/net/netfilter/xt_addrtype.c
@@ -0,0 +1,135 @@
+/*
+ *  iptables module to match inet_addr_type() of an ip.
+ *
+ *  Copyright (c) 2004 Patrick McHardy <kaber@trash.net>
+ *  (C) 2007 Laszlo Attila Toth <panther@balabit.hu>
+ *
+ *  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.
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/skbuff.h>
+#include <linux/netdevice.h>
+#include <linux/ip.h>
+#include <net/route.h>
+
+#include <linux/netfilter/xt_addrtype.h>
+#include <linux/netfilter/x_tables.h>
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
+MODULE_DESCRIPTION("Xtables: address type match");
+MODULE_ALIAS("ipt_addrtype");
+
+static inline bool match_type(struct net *net, const struct net_device *dev,
+			      __be32 addr, u_int16_t mask)
+{
+	return !!(mask & (1 << inet_dev_addr_type(net, dev, addr)));
+}
+
+static bool
+addrtype_mt_v0(const struct sk_buff *skb, struct xt_action_param *par)
+{
+	struct net *net = dev_net(par->in ? par->in : par->out);
+	const struct xt_addrtype_info *info = par->matchinfo;
+	const struct iphdr *iph = ip_hdr(skb);
+	bool ret = true;
+
+	if (info->source)
+		ret &= match_type(net, NULL, iph->saddr, info->source) ^
+		       info->invert_source;
+	if (info->dest)
+		ret &= match_type(net, NULL, iph->daddr, info->dest) ^
+		       info->invert_dest;
+
+	return ret;
+}
+
+static bool
+addrtype_mt_v1(const struct sk_buff *skb, struct xt_action_param *par)
+{
+	struct net *net = dev_net(par->in ? par->in : par->out);
+	const struct xt_addrtype_info_v1 *info = par->matchinfo;
+	const struct iphdr *iph = ip_hdr(skb);
+	const struct net_device *dev = NULL;
+	bool ret = true;
+
+	if (info->flags & XT_ADDRTYPE_LIMIT_IFACE_IN)
+		dev = par->in;
+	else if (info->flags & XT_ADDRTYPE_LIMIT_IFACE_OUT)
+		dev = par->out;
+
+	if (info->source)
+		ret &= match_type(net, dev, iph->saddr, info->source) ^
+		       (info->flags & XT_ADDRTYPE_INVERT_SOURCE);
+	if (ret && info->dest)
+		ret &= match_type(net, dev, iph->daddr, info->dest) ^
+		       !!(info->flags & XT_ADDRTYPE_INVERT_DEST);
+	return ret;
+}
+
+static int addrtype_mt_checkentry_v1(const struct xt_mtchk_param *par)
+{
+	struct xt_addrtype_info_v1 *info = par->matchinfo;
+
+	if (info->flags & XT_ADDRTYPE_LIMIT_IFACE_IN &&
+	    info->flags & XT_ADDRTYPE_LIMIT_IFACE_OUT) {
+		pr_info("both incoming and outgoing "
+			"interface limitation cannot be selected\n");
+		return -EINVAL;
+	}
+
+	if (par->hook_mask & ((1 << NF_INET_PRE_ROUTING) |
+	    (1 << NF_INET_LOCAL_IN)) &&
+	    info->flags & XT_ADDRTYPE_LIMIT_IFACE_OUT) {
+		pr_info("output interface limitation "
+			"not valid in PREROUTING and INPUT\n");
+		return -EINVAL;
+	}
+
+	if (par->hook_mask & ((1 << NF_INET_POST_ROUTING) |
+	    (1 << NF_INET_LOCAL_OUT)) &&
+	    info->flags & XT_ADDRTYPE_LIMIT_IFACE_IN) {
+		pr_info("input interface limitation "
+			"not valid in POSTROUTING and OUTPUT\n");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static struct xt_match addrtype_mt_reg[] __read_mostly = {
+	{
+		.name		= "addrtype",
+		.family		= NFPROTO_IPV4,
+		.match		= addrtype_mt_v0,
+		.matchsize	= sizeof(struct xt_addrtype_info),
+		.me		= THIS_MODULE
+	},
+	{
+		.name		= "addrtype",
+		.family		= NFPROTO_IPV4,
+		.revision	= 1,
+		.match		= addrtype_mt_v1,
+		.checkentry	= addrtype_mt_checkentry_v1,
+		.matchsize	= sizeof(struct xt_addrtype_info_v1),
+		.me		= THIS_MODULE
+	}
+};
+
+static int __init addrtype_mt_init(void)
+{
+	return xt_register_matches(addrtype_mt_reg,
+				   ARRAY_SIZE(addrtype_mt_reg));
+}
+
+static void __exit addrtype_mt_exit(void)
+{
+	xt_unregister_matches(addrtype_mt_reg, ARRAY_SIZE(addrtype_mt_reg));
+}
+
+module_init(addrtype_mt_init);
+module_exit(addrtype_mt_exit);