[NETFILTER]: Convert x_tables matches/targets to centralized error checking

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/netfilter/xt_tcpudp.c b/net/netfilter/xt_tcpudp.c
index 669c811..9d01f07 100644
--- a/net/netfilter/xt_tcpudp.c
+++ b/net/netfilter/xt_tcpudp.c
@@ -142,35 +142,12 @@
 	       unsigned int matchsize,
 	       unsigned int hook_mask)
 {
-	const struct ipt_ip *ip = info;
 	const struct xt_tcp *tcpinfo = matchinfo;
 
-	/* Must specify proto == TCP, and no unknown invflags */
-	return ip->proto == IPPROTO_TCP
-		&& !(ip->invflags & XT_INV_PROTO)
-		&& matchsize == XT_ALIGN(sizeof(struct xt_tcp))
-		&& !(tcpinfo->invflags & ~XT_TCP_INV_MASK);
+	/* Must specify no unknown invflags */
+	return !(tcpinfo->invflags & ~XT_TCP_INV_MASK);
 }
 
-/* Called when user tries to insert an entry of this type. */
-static int
-tcp6_checkentry(const char *tablename,
-	       const void *entry,
-	       void *matchinfo,
-	       unsigned int matchsize,
-	       unsigned int hook_mask)
-{
-	const struct ip6t_ip6 *ipv6 = entry;
-	const struct xt_tcp *tcpinfo = matchinfo;
-
-	/* Must specify proto == TCP, and no unknown invflags */
-	return ipv6->proto == IPPROTO_TCP
-		&& !(ipv6->invflags & XT_INV_PROTO)
-		&& matchsize == XT_ALIGN(sizeof(struct xt_tcp))
-		&& !(tcpinfo->invflags & ~XT_TCP_INV_MASK);
-}
-
-
 static int
 udp_match(const struct sk_buff *skb,
 	  const struct net_device *in,
@@ -209,86 +186,47 @@
 udp_checkentry(const char *tablename,
 	       const void *info,
 	       void *matchinfo,
-	       unsigned int matchinfosize,
+	       unsigned int matchsize,
 	       unsigned int hook_mask)
 {
-	const struct ipt_ip *ip = info;
-	const struct xt_udp *udpinfo = matchinfo;
+	const struct xt_tcp *udpinfo = matchinfo;
 
-	/* Must specify proto == UDP, and no unknown invflags */
-	if (ip->proto != IPPROTO_UDP || (ip->invflags & XT_INV_PROTO)) {
-		duprintf("ipt_udp: Protocol %u != %u\n", ip->proto,
-			 IPPROTO_UDP);
-		return 0;
-	}
-	if (matchinfosize != XT_ALIGN(sizeof(struct xt_udp))) {
-		duprintf("ipt_udp: matchsize %u != %u\n",
-			 matchinfosize, XT_ALIGN(sizeof(struct xt_udp)));
-		return 0;
-	}
-	if (udpinfo->invflags & ~XT_UDP_INV_MASK) {
-		duprintf("ipt_udp: unknown flags %X\n",
-			 udpinfo->invflags);
-		return 0;
-	}
-
-	return 1;
-}
-
-/* Called when user tries to insert an entry of this type. */
-static int
-udp6_checkentry(const char *tablename,
-	       const void *entry,
-	       void *matchinfo,
-	       unsigned int matchinfosize,
-	       unsigned int hook_mask)
-{
-	const struct ip6t_ip6 *ipv6 = entry;
-	const struct xt_udp *udpinfo = matchinfo;
-
-	/* Must specify proto == UDP, and no unknown invflags */
-	if (ipv6->proto != IPPROTO_UDP || (ipv6->invflags & XT_INV_PROTO)) {
-		duprintf("ip6t_udp: Protocol %u != %u\n", ipv6->proto,
-			 IPPROTO_UDP);
-		return 0;
-	}
-	if (matchinfosize != XT_ALIGN(sizeof(struct xt_udp))) {
-		duprintf("ip6t_udp: matchsize %u != %u\n",
-			 matchinfosize, XT_ALIGN(sizeof(struct xt_udp)));
-		return 0;
-	}
-	if (udpinfo->invflags & ~XT_UDP_INV_MASK) {
-		duprintf("ip6t_udp: unknown flags %X\n",
-			 udpinfo->invflags);
-		return 0;
-	}
-
-	return 1;
+	/* Must specify no unknown invflags */
+	return !(udpinfo->invflags & ~XT_UDP_INV_MASK);
 }
 
 static struct xt_match tcp_matchstruct = {
 	.name		= "tcp",
-	.match		= &tcp_match,
-	.checkentry	= &tcp_checkentry,
+	.match		= tcp_match,
+	.matchsize	= sizeof(struct xt_tcp),
+	.proto		= IPPROTO_TCP,
+	.checkentry	= tcp_checkentry,
 	.me		= THIS_MODULE,
 };
+
 static struct xt_match tcp6_matchstruct = {
 	.name		= "tcp",
-	.match		= &tcp_match,
-	.checkentry	= &tcp6_checkentry,
+	.match		= tcp_match,
+	.matchsize	= sizeof(struct xt_tcp),
+	.proto		= IPPROTO_TCP,
+	.checkentry	= tcp_checkentry,
 	.me		= THIS_MODULE,
 };
 
 static struct xt_match udp_matchstruct = {
 	.name		= "udp",
-	.match		= &udp_match,
-	.checkentry	= &udp_checkentry,
+	.match		= udp_match,
+	.matchsize	= sizeof(struct xt_udp),
+	.proto		= IPPROTO_UDP,
+	.checkentry	= udp_checkentry,
 	.me		= THIS_MODULE,
 };
 static struct xt_match udp6_matchstruct = {
 	.name		= "udp",
-	.match		= &udp_match,
-	.checkentry	= &udp6_checkentry,
+	.match		= udp_match,
+	.matchsize	= sizeof(struct xt_udp),
+	.proto		= IPPROTO_UDP,
+	.checkentry	= udp_checkentry,
 	.me		= THIS_MODULE,
 };