Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
		
			
				
	
	
		
			156 lines
		
	
	
	
		
			3.1 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			156 lines
		
	
	
	
		
			3.1 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
/*
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 *	Forwarding decision
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 *	Linux ethernet bridge
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 *
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 *	Authors:
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 *	Lennert Buytenhek		<buytenh@gnu.org>
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 *
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 *	$Id: br_forward.c,v 1.4 2001/08/14 22:05:57 davem Exp $
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 *
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 *	This program is free software; you can redistribute it and/or
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 *	modify it under the terms of the GNU General Public License
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 *	as published by the Free Software Foundation; either version
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 *	2 of the License, or (at your option) any later version.
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 */
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#include <linux/kernel.h>
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#include <linux/netdevice.h>
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#include <linux/skbuff.h>
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#include <linux/netfilter_bridge.h>
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#include "br_private.h"
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static inline int should_deliver(const struct net_bridge_port *p, 
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				 const struct sk_buff *skb)
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{
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	if (skb->dev == p->dev ||
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	    p->state != BR_STATE_FORWARDING)
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		return 0;
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	return 1;
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}
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int br_dev_queue_push_xmit(struct sk_buff *skb)
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{
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	if (skb->len > skb->dev->mtu) 
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		kfree_skb(skb);
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	else {
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#ifdef CONFIG_BRIDGE_NETFILTER
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		/* ip_refrag calls ip_fragment, doesn't copy the MAC header. */
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		nf_bridge_maybe_copy_header(skb);
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#endif
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		skb_push(skb, ETH_HLEN);
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		dev_queue_xmit(skb);
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	}
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	return 0;
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}
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int br_forward_finish(struct sk_buff *skb)
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{
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	NF_HOOK(PF_BRIDGE, NF_BR_POST_ROUTING, skb, NULL, skb->dev,
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			br_dev_queue_push_xmit);
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	return 0;
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}
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static void __br_deliver(const struct net_bridge_port *to, struct sk_buff *skb)
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{
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	skb->dev = to->dev;
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	NF_HOOK(PF_BRIDGE, NF_BR_LOCAL_OUT, skb, NULL, skb->dev,
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			br_forward_finish);
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}
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static void __br_forward(const struct net_bridge_port *to, struct sk_buff *skb)
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{
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	struct net_device *indev;
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	indev = skb->dev;
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	skb->dev = to->dev;
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	skb->ip_summed = CHECKSUM_NONE;
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	NF_HOOK(PF_BRIDGE, NF_BR_FORWARD, skb, indev, skb->dev,
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			br_forward_finish);
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}
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/* called with rcu_read_lock */
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void br_deliver(const struct net_bridge_port *to, struct sk_buff *skb)
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{
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	if (should_deliver(to, skb)) {
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		__br_deliver(to, skb);
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		return;
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	}
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	kfree_skb(skb);
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}
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/* called with rcu_read_lock */
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void br_forward(const struct net_bridge_port *to, struct sk_buff *skb)
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{
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	if (should_deliver(to, skb)) {
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		__br_forward(to, skb);
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		return;
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	}
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	kfree_skb(skb);
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}
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/* called under bridge lock */
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static void br_flood(struct net_bridge *br, struct sk_buff *skb, int clone,
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	void (*__packet_hook)(const struct net_bridge_port *p, 
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			      struct sk_buff *skb))
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{
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	struct net_bridge_port *p;
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	struct net_bridge_port *prev;
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	if (clone) {
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		struct sk_buff *skb2;
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		if ((skb2 = skb_clone(skb, GFP_ATOMIC)) == NULL) {
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			br->statistics.tx_dropped++;
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			return;
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		}
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		skb = skb2;
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	}
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	prev = NULL;
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	list_for_each_entry_rcu(p, &br->port_list, list) {
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		if (should_deliver(p, skb)) {
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			if (prev != NULL) {
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				struct sk_buff *skb2;
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				if ((skb2 = skb_clone(skb, GFP_ATOMIC)) == NULL) {
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					br->statistics.tx_dropped++;
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					kfree_skb(skb);
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					return;
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				}
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				__packet_hook(prev, skb2);
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			}
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			prev = p;
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		}
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	}
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	if (prev != NULL) {
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		__packet_hook(prev, skb);
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		return;
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	}
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	kfree_skb(skb);
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}
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/* called with rcu_read_lock */
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void br_flood_deliver(struct net_bridge *br, struct sk_buff *skb, int clone)
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{
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	br_flood(br, skb, clone, __br_deliver);
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}
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/* called under bridge lock */
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void br_flood_forward(struct net_bridge *br, struct sk_buff *skb, int clone)
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{
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	br_flood(br, skb, clone, __br_forward);
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}
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