[GitHub/mt8127/android_kernel_alcatel_ttab.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)
{
	/* drop mtu oversized packets except tso */
	if (skb->len > skb->dev->mtu && !skb_shinfo(skb)->tso_size)
		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;
	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	{
2a7bc3c9 VD	34	/* drop mtu oversized packets except tso */
2a7bc3c9 VD	35	if (skb->len > skb->dev->mtu && !skb_shinfo(skb)->tso_size)
1da177e4 LT	36	kfree_skb(skb);
	37	else {
	38	#ifdef CONFIG_BRIDGE_NETFILTER
	39	/* ip_refrag calls ip_fragment, doesn't copy the MAC header. */
	40	nf_bridge_maybe_copy_header(skb);
	41	#endif
	42	skb_push(skb, ETH_HLEN);
	43
	44	dev_queue_xmit(skb);
	45	}
	46
	47	return 0;
	48	}
	49
	50	int br_forward_finish(struct sk_buff *skb)
	51	{
	52	NF_HOOK(PF_BRIDGE, NF_BR_POST_ROUTING, skb, NULL, skb->dev,
	53	br_dev_queue_push_xmit);
	54
	55	return 0;
	56	}
	57
	58	static void __br_deliver(const struct net_bridge_port to, struct sk_buff skb)
	59	{
	60	skb->dev = to->dev;
1da177e4 LT	61	NF_HOOK(PF_BRIDGE, NF_BR_LOCAL_OUT, skb, NULL, skb->dev,
	62	br_forward_finish);
	63	}
	64
	65	static void __br_forward(const struct net_bridge_port to, struct sk_buff skb)
	66	{
	67	struct net_device *indev;
	68
	69	indev = skb->dev;
	70	skb->dev = to->dev;
	71	skb->ip_summed = CHECKSUM_NONE;
	72
	73	NF_HOOK(PF_BRIDGE, NF_BR_FORWARD, skb, indev, skb->dev,
	74	br_forward_finish);
	75	}
	76
	77	/* called with rcu_read_lock */
	78	void br_deliver(const struct net_bridge_port to, struct sk_buff skb)
	79	{
	80	if (should_deliver(to, skb)) {
	81	__br_deliver(to, skb);
	82	return;
	83	}
	84
	85	kfree_skb(skb);
	86	}
	87
	88	/* called with rcu_read_lock */
	89	void br_forward(const struct net_bridge_port to, struct sk_buff skb)
	90	{
	91	if (should_deliver(to, skb)) {
	92	__br_forward(to, skb);
	93	return;
	94	}
	95
	96	kfree_skb(skb);
	97	}
	98
	99	/* called under bridge lock */
	100	static void br_flood(struct net_bridge br, struct sk_buff skb, int clone,
	101	void (__packet_hook)(const struct net_bridge_port p,
	102	struct sk_buff *skb))
	103	{
	104	struct net_bridge_port *p;
	105	struct net_bridge_port *prev;
	106
	107	if (clone) {
	108	struct sk_buff *skb2;
	109
	110	if ((skb2 = skb_clone(skb, GFP_ATOMIC)) == NULL) {
	111	br->statistics.tx_dropped++;
	112	return;
	113	}
	114
	115	skb = skb2;
	116	}
	117
	118	prev = NULL;
	119
	120	list_for_each_entry_rcu(p, &br->port_list, list) {
	121	if (should_deliver(p, skb)) {
	122	if (prev != NULL) {
	123	struct sk_buff *skb2;
	124
125	if ((skb2 = skb_clone(skb, GFP_ATOMIC)) == NULL) {
126	br->statistics.tx_dropped++;
127	kfree_skb(skb);
128	return;
129	}
130
131	__packet_hook(prev, skb2);
132	}
133
134	prev = p;
135	}
136	}
137
138	if (prev != NULL) {
139	__packet_hook(prev, skb);
140	return;
141	}
142
143	kfree_skb(skb);
144	}
145
146
147	/* called with rcu_read_lock */
148	void br_flood_deliver(struct net_bridge br, struct sk_buff skb, int clone)
149	{
150	br_flood(br, skb, clone, __br_deliver);
151	}
152
153	/* called under bridge lock */
154	void br_flood_forward(struct net_bridge br, struct sk_buff skb, int clone)
155	{
156	br_flood(br, skb, clone, __br_forward);
157	}