[NETFILTER]: Merge ipt_tos into xt_dscp

Merge ipt_tos into xt_dscp.

Merge ipt_tos (tos v0 match) into xt_dscp. They both match on the same
field in the IPv4 header, so it seems reasonable to keep them in one
piece. This is part one of the implicit 4-patch series to move tos to
xtables and extend it by IPv6.

Signed-off-by: Jan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv4/netfilter/Kconfig

@@ -63,15 +63,6 @@ config IP_NF_MATCH_IPRANGE
 
 	  To compile it as a module, choose M here.  If unsure, say N.
 
-config IP_NF_MATCH_TOS
-	tristate "TOS match support"
-	depends on IP_NF_IPTABLES
-	help
-	  TOS matching allows you to match packets based on the Type Of
-	  Service fields of the IP packet.
-
-	  To compile it as a module, choose M here.  If unsure, say N.
-
 config IP_NF_MATCH_RECENT
 	tristate '"recent" match support'
 	depends on IP_NF_IPTABLES

net/ipv4/netfilter/Makefile

@@ -46,7 +46,6 @@ obj-$(CONFIG_IP_NF_MATCH_AH) += ipt_ah.o
 obj-$(CONFIG_IP_NF_MATCH_ECN) += ipt_ecn.o
 obj-$(CONFIG_IP_NF_MATCH_IPRANGE) += ipt_iprange.o
 obj-$(CONFIG_IP_NF_MATCH_RECENT) += ipt_recent.o
-obj-$(CONFIG_IP_NF_MATCH_TOS) += ipt_tos.o
 obj-$(CONFIG_IP_NF_MATCH_TTL) += ipt_ttl.o
 
 # targets

net/netfilter/Kconfig

@@ -487,14 +487,18 @@ config NETFILTER_XT_MATCH_DCCP
 	  <file:Documentation/kbuild/modules.txt>.  If unsure, say `N'.
 
 config NETFILTER_XT_MATCH_DSCP
-	tristate '"dscp" match support'
+	tristate '"dscp" and "tos" match support'
 	depends on NETFILTER_XTABLES
 	help
 	  This option adds a `DSCP' match, which allows you to match against
 	  the IPv4/IPv6 header DSCP field (differentiated services codepoint).
 
 	  The DSCP field can have any value between 0x0 and 0x3f inclusive.
 
+	  It will also add a "tos" match, which allows you to match packets
+	  based on the Type Of Service fields of the IPv4 packet (which share
+	  the same bits as DSCP).
+
 	  To compile it as a module, choose M here.  If unsure, say N.
 
 config NETFILTER_XT_MATCH_ESP

net/netfilter/xt_dscp.c

@@ -13,14 +13,16 @@
 #include <linux/ipv6.h>
 #include <net/dsfield.h>
 
-#include <linux/netfilter/xt_dscp.h>
 #include <linux/netfilter/x_tables.h>
+#include <linux/netfilter/xt_dscp.h>
+#include <linux/netfilter_ipv4/ipt_tos.h>
 
 MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
-MODULE_DESCRIPTION("x_tables DSCP matching module");
+MODULE_DESCRIPTION("x_tables DSCP/tos matching module");
 MODULE_LICENSE("GPL");
 MODULE_ALIAS("ipt_dscp");
 MODULE_ALIAS("ip6t_dscp");
+MODULE_ALIAS("ipt_tos");
 
 static bool
 dscp_mt(const struct sk_buff *skb, const struct net_device *in,
@@ -60,6 +62,16 @@ dscp_mt_check(const char *tablename, const void *info,
 	return true;
 }
 
+static bool tos_mt_v0(const struct sk_buff *skb, const struct net_device *in,
+                      const struct net_device *out,
+                      const struct xt_match *match, const void *matchinfo,
+                      int offset, unsigned int protoff, bool *hotdrop)
+{
+	const struct ipt_tos_info *info = matchinfo;
+
+	return (ip_hdr(skb)->tos == info->tos) ^ info->invert;
+}
+
 static struct xt_match dscp_mt_reg[] __read_mostly = {
 	{
 		.name		= "dscp",
@@ -77,6 +89,14 @@ static struct xt_match dscp_mt_reg[] __read_mostly = {
 		.matchsize	= sizeof(struct xt_dscp_info),
 		.me		= THIS_MODULE,
 	},
+	{
+		.name		= "tos",
+		.revision	= 0,
+		.family		= AF_INET,
+		.match		= tos_mt_v0,
+		.matchsize	= sizeof(struct ipt_tos_info),
+		.me		= THIS_MODULE,
+	},
 };
 
 static int __init dscp_mt_init(void)