[NETFILTER]: Move ipv4 specific code from net/core/netfilter.c to net/ipv4/netfilter.c

Netfilter cleanup
- Move ipv4 code from net/core/netfilter.c to net/ipv4/netfilter.c
- Move ipv6 netfilter code from net/ipv6/ip6_output.c to net/ipv6/netfilter.c

Signed-off-by: Harald Welte <laforge@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/core/netfilter.c

@@ -22,12 +22,7 @@
 #include <linux/if.h>
 #include <linux/netdevice.h>
 #include <linux/inetdevice.h>
-#include <linux/tcp.h>
-#include <linux/udp.h>
-#include <linux/icmp.h>
 #include <net/sock.h>
-#include <net/route.h>
-#include <linux/ip.h>
 
 /* In this code, we can be waiting indefinitely for userspace to
  * service a packet if a hook returns NF_QUEUE.  We could keep a count
@@ -447,73 +442,6 @@ void nf_reinject(struct sk_buff *skb, struct nf_info *info,
 	return;
 }
 
-#ifdef CONFIG_INET
-/* route_me_harder function, used by iptable_nat, iptable_mangle + ip_queue */
-int ip_route_me_harder(struct sk_buff **pskb)
-{
-	struct iphdr *iph = (*pskb)->nh.iph;
-	struct rtable *rt;
-	struct flowi fl = {};
-	struct dst_entry *odst;
-	unsigned int hh_len;
-
-	/* some non-standard hacks like ipt_REJECT.c:send_reset() can cause
-	 * packets with foreign saddr to appear on the NF_IP_LOCAL_OUT hook.
-	 */
-	if (inet_addr_type(iph->saddr) == RTN_LOCAL) {
-		fl.nl_u.ip4_u.daddr = iph->daddr;
-		fl.nl_u.ip4_u.saddr = iph->saddr;
-		fl.nl_u.ip4_u.tos = RT_TOS(iph->tos);
-		fl.oif = (*pskb)->sk ? (*pskb)->sk->sk_bound_dev_if : 0;
-#ifdef CONFIG_IP_ROUTE_FWMARK
-		fl.nl_u.ip4_u.fwmark = (*pskb)->nfmark;
-#endif
-		fl.proto = iph->protocol;
-		if (ip_route_output_key(&rt, &fl) != 0)
-			return -1;
-
-		/* Drop old route. */
-		dst_release((*pskb)->dst);
-		(*pskb)->dst = &rt->u.dst;
-	} else {
-		/* non-local src, find valid iif to satisfy
-		 * rp-filter when calling ip_route_input. */
-		fl.nl_u.ip4_u.daddr = iph->saddr;
-		if (ip_route_output_key(&rt, &fl) != 0)
-			return -1;
-
-		odst = (*pskb)->dst;
-		if (ip_route_input(*pskb, iph->daddr, iph->saddr,
-				   RT_TOS(iph->tos), rt->u.dst.dev) != 0) {
-			dst_release(&rt->u.dst);
-			return -1;
-		}
-		dst_release(&rt->u.dst);
-		dst_release(odst);
-	}
-	
-	if ((*pskb)->dst->error)
-		return -1;
-
-	/* Change in oif may mean change in hh_len. */
-	hh_len = (*pskb)->dst->dev->hard_header_len;
-	if (skb_headroom(*pskb) < hh_len) {
-		struct sk_buff *nskb;
-
-		nskb = skb_realloc_headroom(*pskb, hh_len);
-		if (!nskb) 
-			return -1;
-		if ((*pskb)->sk)
-			skb_set_owner_w(nskb, (*pskb)->sk);
-		kfree_skb(*pskb);
-		*pskb = nskb;
-	}
-
-	return 0;
-}
-EXPORT_SYMBOL(ip_route_me_harder);
-#endif /*CONFIG_INET*/
-
 int skb_make_writable(struct sk_buff **pskb, unsigned int writable_len)
 {
 	struct sk_buff *nskb;

net/ipv4/Makefile

@@ -8,7 +8,7 @@ obj-y     := route.o inetpeer.o protocol.o \
 	     tcp.o tcp_input.o tcp_output.o tcp_timer.o tcp_ipv4.o \
 	     tcp_minisocks.o tcp_cong.o \
 	     datagram.o raw.o udp.o arp.o icmp.o devinet.o af_inet.o igmp.o \
-	     sysctl_net_ipv4.o fib_frontend.o fib_semantics.o
+	     sysctl_net_ipv4.o fib_frontend.o fib_semantics.o netfilter.o
 
 obj-$(CONFIG_IP_FIB_HASH) += fib_hash.o
 obj-$(CONFIG_IP_FIB_TRIE) += fib_trie.o

net/ipv4/netfilter.c

@@ -0,0 +1,79 @@
+#include <linux/config.h>
+
+#ifdef CONFIG_NETFILTER
+
+/* IPv4 specific functions of netfilter core */
+#include <linux/kernel.h>
+#include <linux/netfilter.h>
+
+#include <linux/tcp.h>
+#include <linux/udp.h>
+#include <linux/icmp.h>
+#include <net/route.h>
+#include <linux/ip.h>
+
+/* route_me_harder function, used by iptable_nat, iptable_mangle + ip_queue */
+int ip_route_me_harder(struct sk_buff **pskb)
+{
+	struct iphdr *iph = (*pskb)->nh.iph;
+	struct rtable *rt;
+	struct flowi fl = {};
+	struct dst_entry *odst;
+	unsigned int hh_len;
+
+	/* some non-standard hacks like ipt_REJECT.c:send_reset() can cause
+	 * packets with foreign saddr to appear on the NF_IP_LOCAL_OUT hook.
+	 */
+	if (inet_addr_type(iph->saddr) == RTN_LOCAL) {
+		fl.nl_u.ip4_u.daddr = iph->daddr;
+		fl.nl_u.ip4_u.saddr = iph->saddr;
+		fl.nl_u.ip4_u.tos = RT_TOS(iph->tos);
+		fl.oif = (*pskb)->sk ? (*pskb)->sk->sk_bound_dev_if : 0;
+#ifdef CONFIG_IP_ROUTE_FWMARK
+		fl.nl_u.ip4_u.fwmark = (*pskb)->nfmark;
+#endif
+		fl.proto = iph->protocol;
+		if (ip_route_output_key(&rt, &fl) != 0)
+			return -1;
+
+		/* Drop old route. */
+		dst_release((*pskb)->dst);
+		(*pskb)->dst = &rt->u.dst;
+	} else {
+		/* non-local src, find valid iif to satisfy
+		 * rp-filter when calling ip_route_input. */
+		fl.nl_u.ip4_u.daddr = iph->saddr;
+		if (ip_route_output_key(&rt, &fl) != 0)
+			return -1;
+
+		odst = (*pskb)->dst;
+		if (ip_route_input(*pskb, iph->daddr, iph->saddr,
+				   RT_TOS(iph->tos), rt->u.dst.dev) != 0) {
+			dst_release(&rt->u.dst);
+			return -1;
+		}
+		dst_release(&rt->u.dst);
+		dst_release(odst);
+	}
+	
+	if ((*pskb)->dst->error)
+		return -1;
+
+	/* Change in oif may mean change in hh_len. */
+	hh_len = (*pskb)->dst->dev->hard_header_len;
+	if (skb_headroom(*pskb) < hh_len) {
+		struct sk_buff *nskb;
+
+		nskb = skb_realloc_headroom(*pskb, hh_len);
+		if (!nskb) 
+			return -1;
+		if ((*pskb)->sk)
+			skb_set_owner_w(nskb, (*pskb)->sk);
+		kfree_skb(*pskb);
+		*pskb = nskb;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL(ip_route_me_harder);
+#endif /* CONFIG_NETFILTER */

net/ipv6/Makefile

@@ -8,7 +8,7 @@ ipv6-objs :=	af_inet6.o anycast.o ip6_output.o ip6_input.o addrconf.o sit.o \
 		route.o ip6_fib.o ipv6_sockglue.o ndisc.o udp.o raw.o \
 		protocol.o icmp.o mcast.o reassembly.o tcp_ipv6.o \
 		exthdrs.o sysctl_net_ipv6.o datagram.o proc.o \
-		ip6_flowlabel.o ipv6_syms.o
+		ip6_flowlabel.o ipv6_syms.o netfilter.o
 
 ipv6-$(CONFIG_XFRM) += xfrm6_policy.o xfrm6_state.o xfrm6_input.o \
 	xfrm6_output.o

net/ipv6/ip6_output.c

@@ -153,38 +153,6 @@ int ip6_output(struct sk_buff *skb)
 		return ip6_output2(skb);
 }
 
-#ifdef CONFIG_NETFILTER
-int ip6_route_me_harder(struct sk_buff *skb)
-{
-	struct ipv6hdr *iph = skb->nh.ipv6h;
-	struct dst_entry *dst;
-	struct flowi fl = {
-		.oif = skb->sk ? skb->sk->sk_bound_dev_if : 0,
-		.nl_u =
-		{ .ip6_u =
-		  { .daddr = iph->daddr,
-		    .saddr = iph->saddr, } },
-		.proto = iph->nexthdr,
-	};
-
-	dst = ip6_route_output(skb->sk, &fl);
-
-	if (dst->error) {
-		IP6_INC_STATS(IPSTATS_MIB_OUTNOROUTES);
-		LIMIT_NETDEBUG(
-			printk(KERN_DEBUG "ip6_route_me_harder: No more route.\n"));
-		dst_release(dst);
-		return -EINVAL;
-	}
-
-	/* Drop old route. */
-	dst_release(skb->dst);
-
-	skb->dst = dst;
-	return 0;
-}
-#endif
-
 /*
  *	xmit an sk_buff (used by TCP)
  */

net/ipv6/ipv6_syms.c

@@ -15,9 +15,6 @@ EXPORT_SYMBOL(ndisc_mc_map);
 EXPORT_SYMBOL(register_inet6addr_notifier);
 EXPORT_SYMBOL(unregister_inet6addr_notifier);
 EXPORT_SYMBOL(ip6_route_output);
-#ifdef CONFIG_NETFILTER
-EXPORT_SYMBOL(ip6_route_me_harder);
-#endif
 EXPORT_SYMBOL(addrconf_lock);
 EXPORT_SYMBOL(ipv6_setsockopt);
 EXPORT_SYMBOL(ipv6_getsockopt);

net/ipv6/netfilter.c

@@ -0,0 +1,43 @@
+#include <linux/config.h>
+#include <linux/init.h>
+
+#ifdef CONFIG_NETFILTER
+
+#include <linux/kernel.h>
+#include <linux/ipv6.h>
+#include <net/dst.h>
+#include <net/ipv6.h>
+#include <net/ip6_route.h>
+
+int ip6_route_me_harder(struct sk_buff *skb)
+{
+	struct ipv6hdr *iph = skb->nh.ipv6h;
+	struct dst_entry *dst;
+	struct flowi fl = {
+		.oif = skb->sk ? skb->sk->sk_bound_dev_if : 0,
+		.nl_u =
+		{ .ip6_u =
+		  { .daddr = iph->daddr,
+		    .saddr = iph->saddr, } },
+		.proto = iph->nexthdr,
+	};
+
+	dst = ip6_route_output(skb->sk, &fl);
+
+	if (dst->error) {
+		IP6_INC_STATS(IPSTATS_MIB_OUTNOROUTES);
+		LIMIT_NETDEBUG(
+			printk(KERN_DEBUG "ip6_route_me_harder: No more route.\n"));
+		dst_release(dst);
+		return -EINVAL;
+	}
+
+	/* Drop old route. */
+	dst_release(skb->dst);
+
+	skb->dst = dst;
+	return 0;
+}
+EXPORT_SYMBOL(ip6_route_me_harder);
+
+#endif /* CONFIG_NETFILTER */