[linux-block.git] / net / bridge / br_forward.c

/*
 *	Forwarding decision
 *	Linux ethernet bridge
 *
 *	Authors:
 *	Lennert Buytenhek		<buytenh@gnu.org>
 *
 *	$Id: br_forward.c,v 1.4 2001/08/14 22:05:57 davem Exp $
 *
 *	This program is free software; you can redistribute it and/or
 *	modify it under the terms of the GNU General Public License
 *	as published by the Free Software Foundation; either version
 *	2 of the License, or (at your option) any later version.
 */

#include <linux/kernel.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <linux/netfilter_bridge.h>
#include "br_private.h"

static inline int should_deliver(const struct net_bridge_port *p, 
				 const struct sk_buff *skb)
{
	if (skb->dev == p->dev ||
	    p->state != BR_STATE_FORWARDING)
		return 0;

	return 1;
}

int br_dev_queue_push_xmit(struct sk_buff *skb)
{
	if (skb->len > skb->dev->mtu) 
		kfree_skb(skb);
	else {
#ifdef CONFIG_BRIDGE_NETFILTER
		/* ip_refrag calls ip_fragment, doesn't copy the MAC header. */
		nf_bridge_maybe_copy_header(skb);
#endif
		skb_push(skb, ETH_HLEN);

		dev_queue_xmit(skb);
	}

	return 0;
}

int br_forward_finish(struct sk_buff *skb)
{
	NF_HOOK(PF_BRIDGE, NF_BR_POST_ROUTING, skb, NULL, skb->dev,
			br_dev_queue_push_xmit);

	return 0;
}

static void __br_deliver(const struct net_bridge_port *to, struct sk_buff *skb)
{
	skb->dev = to->dev;
#ifdef CONFIG_NETFILTER_DEBUG
	skb->nf_debug = 0;
#endif
	NF_HOOK(PF_BRIDGE, NF_BR_LOCAL_OUT, skb, NULL, skb->dev,
			br_forward_finish);
}

static void __br_forward(const struct net_bridge_port *to, struct sk_buff *skb)
{
	struct net_device *indev;

	indev = skb->dev;
	skb->dev = to->dev;
	skb->ip_summed = CHECKSUM_NONE;

	NF_HOOK(PF_BRIDGE, NF_BR_FORWARD, skb, indev, skb->dev,
			br_forward_finish);
}

/* called with rcu_read_lock */
void br_deliver(const struct net_bridge_port *to, struct sk_buff *skb)
{
	if (should_deliver(to, skb)) {
		__br_deliver(to, skb);
		return;
	}

	kfree_skb(skb);
}

/* called with rcu_read_lock */
void br_forward(const struct net_bridge_port *to, struct sk_buff *skb)
{
	if (should_deliver(to, skb)) {
		__br_forward(to, skb);
		return;
	}

	kfree_skb(skb);
}

/* called under bridge lock */
static void br_flood(struct net_bridge *br, struct sk_buff *skb, int clone,
	void (*__packet_hook)(const struct net_bridge_port *p, 
			      struct sk_buff *skb))
{
	struct net_bridge_port *p;
	struct net_bridge_port *prev;

	if (clone) {
		struct sk_buff *skb2;

		if ((skb2 = skb_clone(skb, GFP_ATOMIC)) == NULL) {
			br->statistics.tx_dropped++;
			return;
		}

		skb = skb2;
	}

	prev = NULL;

	list_for_each_entry_rcu(p, &br->port_list, list) {
		if (should_deliver(p, skb)) {
			if (prev != NULL) {
				struct sk_buff *skb2;

				if ((skb2 = skb_clone(skb, GFP_ATOMIC)) == NULL) {
					br->statistics.tx_dropped++;
					kfree_skb(skb);
					return;
				}

				__packet_hook(prev, skb2);
			}

			prev = p;
		}
	}

	if (prev != NULL) {
		__packet_hook(prev, skb);
		return;
	}

	kfree_skb(skb);
}


/* called with rcu_read_lock */
void br_flood_deliver(struct net_bridge *br, struct sk_buff *skb, int clone)
{
	br_flood(br, skb, clone, __br_deliver);
}

/* called under bridge lock */
void br_flood_forward(struct net_bridge *br, struct sk_buff *skb, int clone)
{
	br_flood(br, skb, clone, __br_forward);
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* Forwarding decision
	3	* Linux ethernet bridge
	4	*
	5	* Authors:
	6	* Lennert Buytenhek <buytenh@gnu.org>
	7	*
	8	* $Id: br_forward.c,v 1.4 2001/08/14 22:05:57 davem Exp $
	9	*
	10	* This program is free software; you can redistribute it and/or
	11	* modify it under the terms of the GNU General Public License
	12	* as published by the Free Software Foundation; either version
	13	* 2 of the License, or (at your option) any later version.
	14	*/
	15
	16	#include <linux/kernel.h>
	17	#include <linux/netdevice.h>
	18	#include <linux/skbuff.h>
	19	#include <linux/netfilter_bridge.h>
	20	#include "br_private.h"
	21
	22	static inline int should_deliver(const struct net_bridge_port *p,
	23	const struct sk_buff *skb)
	24	{
	25	if (skb->dev == p->dev \|\|
	26	p->state != BR_STATE_FORWARDING)
	27	return 0;
	28
	29	return 1;
	30	}
	31
	32	int br_dev_queue_push_xmit(struct sk_buff *skb)
	33	{
	34	if (skb->len > skb->dev->mtu)
	35	kfree_skb(skb);
	36	else {
	37	#ifdef CONFIG_BRIDGE_NETFILTER
	38	/* ip_refrag calls ip_fragment, doesn't copy the MAC header. */
	39	nf_bridge_maybe_copy_header(skb);
	40	#endif
	41	skb_push(skb, ETH_HLEN);
	42
	43	dev_queue_xmit(skb);
	44	}
	45
	46	return 0;
	47	}
	48
	49	int br_forward_finish(struct sk_buff *skb)
	50	{
	51	NF_HOOK(PF_BRIDGE, NF_BR_POST_ROUTING, skb, NULL, skb->dev,
	52	br_dev_queue_push_xmit);
	53
	54	return 0;
	55	}
	56
	57	static void __br_deliver(const struct net_bridge_port to, struct sk_buff skb)
	58	{
	59	skb->dev = to->dev;
	60	#ifdef CONFIG_NETFILTER_DEBUG
	61	skb->nf_debug = 0;
	62	#endif
	63	NF_HOOK(PF_BRIDGE, NF_BR_LOCAL_OUT, skb, NULL, skb->dev,
	64	br_forward_finish);
65	}
66
67	static void __br_forward(const struct net_bridge_port to, struct sk_buff skb)
68	{
69	struct net_device *indev;
70
71	indev = skb->dev;
72	skb->dev = to->dev;
73	skb->ip_summed = CHECKSUM_NONE;
74
75	NF_HOOK(PF_BRIDGE, NF_BR_FORWARD, skb, indev, skb->dev,
76	br_forward_finish);
77	}
78
79	/* called with rcu_read_lock */
80	void br_deliver(const struct net_bridge_port to, struct sk_buff skb)
81	{
82	if (should_deliver(to, skb)) {
83	__br_deliver(to, skb);
84	return;
85	}
86
87	kfree_skb(skb);
88	}
89
90	/* called with rcu_read_lock */
91	void br_forward(const struct net_bridge_port to, struct sk_buff skb)
92	{
93	if (should_deliver(to, skb)) {
94	__br_forward(to, skb);
95	return;
96	}
97
98	kfree_skb(skb);
99	}
100
101	/* called under bridge lock */
102	static void br_flood(struct net_bridge br, struct sk_buff skb, int clone,
103	void (__packet_hook)(const struct net_bridge_port p,
104	struct sk_buff *skb))
105	{
106	struct net_bridge_port *p;
107	struct net_bridge_port *prev;
108
109	if (clone) {
110	struct sk_buff *skb2;
111
112	if ((skb2 = skb_clone(skb, GFP_ATOMIC)) == NULL) {
113	br->statistics.tx_dropped++;
114	return;
115	}
116
117	skb = skb2;
118	}
119
120	prev = NULL;
121
122	list_for_each_entry_rcu(p, &br->port_list, list) {
123	if (should_deliver(p, skb)) {
124	if (prev != NULL) {
125	struct sk_buff *skb2;
126
127	if ((skb2 = skb_clone(skb, GFP_ATOMIC)) == NULL) {
128	br->statistics.tx_dropped++;
129	kfree_skb(skb);
130	return;
131	}
132
133	__packet_hook(prev, skb2);
134	}
135
136	prev = p;
137	}
138	}
139
140	if (prev != NULL) {
141	__packet_hook(prev, skb);
142	return;
143	}
144
145	kfree_skb(skb);
146	}
147
148
149	/* called with rcu_read_lock */
150	void br_flood_deliver(struct net_bridge br, struct sk_buff skb, int clone)
151	{
152	br_flood(br, skb, clone, __br_deliver);
153	}
154
155	/* called under bridge lock */
156	void br_flood_forward(struct net_bridge br, struct sk_buff skb, int clone)
157	{
158	br_flood(br, skb, clone, __br_forward);
159	}