[linux-block.git] / net / x25 / x25_forward.c

/*
 *	This module:
 *		This module 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.
 *
 *	History
 *	03-01-2007	Added forwarding for x.25	Andrew Hendry
 */
#include <linux/if_arp.h>
#include <linux/init.h>
#include <net/x25.h>

LIST_HEAD(x25_forward_list);
DEFINE_RWLOCK(x25_forward_list_lock);

int x25_forward_call(struct x25_address *dest_addr, struct x25_neigh *from,
			struct sk_buff *skb, int lci)
{
	struct x25_route *rt;
	struct x25_neigh *neigh_new = NULL;
	struct list_head *entry;
	struct x25_forward *x25_frwd, *new_frwd;
	struct sk_buff *skbn;
	short same_lci = 0;
	int rc = 0;

	if ((rt = x25_get_route(dest_addr)) == NULL)
		goto out_no_route;

	if ((neigh_new = x25_get_neigh(rt->dev)) == NULL) {
		/* This shouldnt happen, if it occurs somehow
		 * do something sensible
		 */
		goto out_put_route;
	}

	/* Avoid a loop. This is the normal exit path for a
	 * system with only one x.25 iface and default route
	 */
	if (rt->dev == from->dev) {
		goto out_put_nb;
	}

	/* Remote end sending a call request on an already
	 * established LCI? It shouldnt happen, just in case..
	 */
	read_lock_bh(&x25_forward_list_lock);
	list_for_each(entry, &x25_forward_list) {
		x25_frwd = list_entry(entry, struct x25_forward, node);
		if (x25_frwd->lci == lci) {
			printk(KERN_WARNING "X.25: call request for lci which is already registered!, transmitting but not registering new pair\n");
			same_lci = 1;
		}
	}
	read_unlock_bh(&x25_forward_list_lock);

	/* Save the forwarding details for future traffic */
	if (!same_lci){
		if ((new_frwd = kmalloc(sizeof(struct x25_forward),
						GFP_ATOMIC)) == NULL){
			rc = -ENOMEM;
			goto out_put_nb;
		}
		new_frwd->lci = lci;
		new_frwd->dev1 = rt->dev;
		new_frwd->dev2 = from->dev;
		write_lock_bh(&x25_forward_list_lock);
		list_add(&new_frwd->node, &x25_forward_list);
		write_unlock_bh(&x25_forward_list_lock);
	}

	/* Forward the call request */
	if ( (skbn = skb_clone(skb, GFP_ATOMIC)) == NULL){
		goto out_put_nb;
	}
	x25_transmit_link(skbn, neigh_new);
	rc = 1;


out_put_nb:
	x25_neigh_put(neigh_new);

out_put_route:
	x25_route_put(rt);

out_no_route:
	return rc;
}


int x25_forward_data(int lci, struct x25_neigh *from, struct sk_buff *skb) {

	struct x25_forward *frwd;
	struct list_head *entry;
	struct net_device *peer = NULL;
	struct x25_neigh *nb;
	struct sk_buff *skbn;
	int rc = 0;

	read_lock_bh(&x25_forward_list_lock);
	list_for_each(entry, &x25_forward_list) {
		frwd = list_entry(entry, struct x25_forward, node);
		if (frwd->lci == lci) {
			/* The call is established, either side can send */
			if (from->dev == frwd->dev1) {
				peer = frwd->dev2;
			} else {
				peer = frwd->dev1;
			}
			break;
		}
	}
	read_unlock_bh(&x25_forward_list_lock);

	if ( (nb = x25_get_neigh(peer)) == NULL)
		goto out;

	if ( (skbn = pskb_copy(skb, GFP_ATOMIC)) == NULL){
		goto output;

	}
	x25_transmit_link(skbn, nb);

	rc = 1;
output:
	x25_neigh_put(nb);
out:
	return rc;
}

void x25_clear_forward_by_lci(unsigned int lci)
{
	struct x25_forward *fwd;
	struct list_head *entry, *tmp;

	write_lock_bh(&x25_forward_list_lock);

	list_for_each_safe(entry, tmp, &x25_forward_list) {
		fwd = list_entry(entry, struct x25_forward, node);
		if (fwd->lci == lci) {
			list_del(&fwd->node);
			kfree(fwd);
		}
	}
	write_unlock_bh(&x25_forward_list_lock);
}


void x25_clear_forward_by_dev(struct net_device *dev)
{
	struct x25_forward *fwd;
	struct list_head *entry, *tmp;

	write_lock_bh(&x25_forward_list_lock);

	list_for_each_safe(entry, tmp, &x25_forward_list) {
		fwd = list_entry(entry, struct x25_forward, node);
		if ((fwd->dev1 == dev) || (fwd->dev2 == dev)){
			list_del(&fwd->node);
			kfree(fwd);
		}
	}
	write_unlock_bh(&x25_forward_list_lock);
}
Commit	Line	Data
95a9dc43 AH	1	/*
	2	* This module:
	3	* This module is free software; you can redistribute it and/or
	4	* modify it under the terms of the GNU General Public License
	5	* as published by the Free Software Foundation; either version
	6	* 2 of the License, or (at your option) any later version.
	7	*
	8	* History
	9	* 03-01-2007 Added forwarding for x.25 Andrew Hendry
	10	*/
	11	#include <linux/if_arp.h>
	12	#include <linux/init.h>
	13	#include <net/x25.h>
	14
0e3cf7e9	15	LIST_HEAD(x25_forward_list);
95a9dc43 AH	16	DEFINE_RWLOCK(x25_forward_list_lock);
	17
	18	int x25_forward_call(struct x25_address dest_addr, struct x25_neigh from,
	19	struct sk_buff *skb, int lci)
	20	{
	21	struct x25_route *rt;
	22	struct x25_neigh *neigh_new = NULL;
	23	struct list_head *entry;
	24	struct x25_forward x25_frwd, new_frwd;
	25	struct sk_buff *skbn;
	26	short same_lci = 0;
	27	int rc = 0;
	28
e4ce837d AB	29	if ((rt = x25_get_route(dest_addr)) == NULL)
e4ce837d AB	30	goto out_no_route;
95a9dc43	31
e4ce837d AB	32	if ((neigh_new = x25_get_neigh(rt->dev)) == NULL) {
	33	/* This shouldnt happen, if it occurs somehow
	34	* do something sensible
95a9dc43	35	*/
e4ce837d AB	36	goto out_put_route;
e4ce837d AB	37	}
95a9dc43	38
e4ce837d AB	39	/* Avoid a loop. This is the normal exit path for a
	40	* system with only one x.25 iface and default route
	41	*/
	42	if (rt->dev == from->dev) {
	43	goto out_put_nb;
	44	}
	45
	46	/* Remote end sending a call request on an already
	47	* established LCI? It shouldnt happen, just in case..
	48	*/
	49	read_lock_bh(&x25_forward_list_lock);
	50	list_for_each(entry, &x25_forward_list) {
	51	x25_frwd = list_entry(entry, struct x25_forward, node);
	52	if (x25_frwd->lci == lci) {
	53	printk(KERN_WARNING "X.25: call request for lci which is already registered!, transmitting but not registering new pair\n");
	54	same_lci = 1;
95a9dc43	55	}
e4ce837d AB	56	}
e4ce837d AB	57	read_unlock_bh(&x25_forward_list_lock);
95a9dc43	58
e4ce837d AB	59	/* Save the forwarding details for future traffic */
	60	if (!same_lci){
	61	if ((new_frwd = kmalloc(sizeof(struct x25_forward),
	62	GFP_ATOMIC)) == NULL){
	63	rc = -ENOMEM;
95a9dc43 AH	64	goto out_put_nb;
95a9dc43 AH	65	}
e4ce837d AB	66	new_frwd->lci = lci;
	67	new_frwd->dev1 = rt->dev;
	68	new_frwd->dev2 = from->dev;
	69	write_lock_bh(&x25_forward_list_lock);
	70	list_add(&new_frwd->node, &x25_forward_list);
	71	write_unlock_bh(&x25_forward_list_lock);
	72	}
	73
	74	/* Forward the call request */
	75	if ( (skbn = skb_clone(skb, GFP_ATOMIC)) == NULL){
	76	goto out_put_nb;
95a9dc43	77	}
e4ce837d AB	78	x25_transmit_link(skbn, neigh_new);
e4ce837d AB	79	rc = 1;
95a9dc43 AH	80
	81
	82	out_put_nb:
	83	x25_neigh_put(neigh_new);
	84
	85	out_put_route:
	86	x25_route_put(rt);
e4ce837d AB	87
e4ce837d AB	88	out_no_route:
95a9dc43 AH	89	return rc;
	90	}
	91
	92
	93	int x25_forward_data(int lci, struct x25_neigh from, struct sk_buff skb) {
	94
	95	struct x25_forward *frwd;
	96	struct list_head *entry;
	97	struct net_device *peer = NULL;
	98	struct x25_neigh *nb;
	99	struct sk_buff *skbn;
	100	int rc = 0;
	101
	102	read_lock_bh(&x25_forward_list_lock);
	103	list_for_each(entry, &x25_forward_list) {
	104	frwd = list_entry(entry, struct x25_forward, node);
	105	if (frwd->lci == lci) {
	106	/* The call is established, either side can send */
	107	if (from->dev == frwd->dev1) {
	108	peer = frwd->dev2;
	109	} else {
	110	peer = frwd->dev1;
	111	}
	112	break;
	113	}
	114	}
	115	read_unlock_bh(&x25_forward_list_lock);
	116
	117	if ( (nb = x25_get_neigh(peer)) == NULL)
	118	goto out;
	119
	120	if ( (skbn = pskb_copy(skb, GFP_ATOMIC)) == NULL){
76975f8a	121	goto output;
95a9dc43 AH	122
	123	}
	124	x25_transmit_link(skbn, nb);
	125
95a9dc43	126	rc = 1;
76975f8a JL	127	output:
76975f8a JL	128	x25_neigh_put(nb);
95a9dc43 AH	129	out:
	130	return rc;
	131	}
	132
	133	void x25_clear_forward_by_lci(unsigned int lci)
	134	{
	135	struct x25_forward *fwd;
	136	struct list_head entry, tmp;
	137
	138	write_lock_bh(&x25_forward_list_lock);
	139
	140	list_for_each_safe(entry, tmp, &x25_forward_list) {
	141	fwd = list_entry(entry, struct x25_forward, node);
	142	if (fwd->lci == lci) {
	143	list_del(&fwd->node);
	144	kfree(fwd);
	145	}
	146	}
	147	write_unlock_bh(&x25_forward_list_lock);
	148	}
	149
	150
	151	void x25_clear_forward_by_dev(struct net_device *dev)
	152	{
	153	struct x25_forward *fwd;
	154	struct list_head entry, tmp;
	155
	156	write_lock_bh(&x25_forward_list_lock);
	157
	158	list_for_each_safe(entry, tmp, &x25_forward_list) {
	159	fwd = list_entry(entry, struct x25_forward, node);
	160	if ((fwd->dev1 == dev) \|\| (fwd->dev2 == dev)){
	161	list_del(&fwd->node);
	162	kfree(fwd);
	163	}
	164	}
	165	write_unlock_bh(&x25_forward_list_lock);
	166	}