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v4.10.11
  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
 12#define pr_fmt(fmt) "X25: " fmt
 13
 14#include <linux/if_arp.h>
 15#include <linux/init.h>
 16#include <linux/slab.h>
 17#include <net/x25.h>
 18
 19LIST_HEAD(x25_forward_list);
 20DEFINE_RWLOCK(x25_forward_list_lock);
 21
 22int x25_forward_call(struct x25_address *dest_addr, struct x25_neigh *from,
 23			struct sk_buff *skb, int lci)
 24{
 25	struct x25_route *rt;
 26	struct x25_neigh *neigh_new = NULL;
 27	struct list_head *entry;
 28	struct x25_forward *x25_frwd, *new_frwd;
 29	struct sk_buff *skbn;
 30	short same_lci = 0;
 31	int rc = 0;
 32
 33	if ((rt = x25_get_route(dest_addr)) == NULL)
 34		goto out_no_route;
 35
 36	if ((neigh_new = x25_get_neigh(rt->dev)) == NULL) {
 37		/* This shouldn't happen, if it occurs somehow
 38		 * do something sensible
 39		 */
 40		goto out_put_route;
 41	}
 42
 43	/* Avoid a loop. This is the normal exit path for a
 44	 * system with only one x.25 iface and default route
 45	 */
 46	if (rt->dev == from->dev) {
 47		goto out_put_nb;
 48	}
 49
 50	/* Remote end sending a call request on an already
 51	 * established LCI? It shouldn't happen, just in case..
 52	 */
 53	read_lock_bh(&x25_forward_list_lock);
 54	list_for_each(entry, &x25_forward_list) {
 55		x25_frwd = list_entry(entry, struct x25_forward, node);
 56		if (x25_frwd->lci == lci) {
 57			pr_warn("call request for lci which is already registered!, transmitting but not registering new pair\n");
 58			same_lci = 1;
 59		}
 60	}
 61	read_unlock_bh(&x25_forward_list_lock);
 62
 63	/* Save the forwarding details for future traffic */
 64	if (!same_lci){
 65		if ((new_frwd = kmalloc(sizeof(struct x25_forward),
 66						GFP_ATOMIC)) == NULL){
 67			rc = -ENOMEM;
 68			goto out_put_nb;
 69		}
 70		new_frwd->lci = lci;
 71		new_frwd->dev1 = rt->dev;
 72		new_frwd->dev2 = from->dev;
 73		write_lock_bh(&x25_forward_list_lock);
 74		list_add(&new_frwd->node, &x25_forward_list);
 75		write_unlock_bh(&x25_forward_list_lock);
 76	}
 77
 78	/* Forward the call request */
 79	if ( (skbn = skb_clone(skb, GFP_ATOMIC)) == NULL){
 80		goto out_put_nb;
 81	}
 82	x25_transmit_link(skbn, neigh_new);
 83	rc = 1;
 84
 85
 86out_put_nb:
 87	x25_neigh_put(neigh_new);
 88
 89out_put_route:
 90	x25_route_put(rt);
 91
 92out_no_route:
 93	return rc;
 94}
 95
 96
 97int x25_forward_data(int lci, struct x25_neigh *from, struct sk_buff *skb) {
 98
 99	struct x25_forward *frwd;
100	struct list_head *entry;
101	struct net_device *peer = NULL;
102	struct x25_neigh *nb;
103	struct sk_buff *skbn;
104	int rc = 0;
105
106	read_lock_bh(&x25_forward_list_lock);
107	list_for_each(entry, &x25_forward_list) {
108		frwd = list_entry(entry, struct x25_forward, node);
109		if (frwd->lci == lci) {
110			/* The call is established, either side can send */
111			if (from->dev == frwd->dev1) {
112				peer = frwd->dev2;
113			} else {
114				peer = frwd->dev1;
115			}
116			break;
117		}
118	}
119	read_unlock_bh(&x25_forward_list_lock);
120
121	if ( (nb = x25_get_neigh(peer)) == NULL)
122		goto out;
123
124	if ( (skbn = pskb_copy(skb, GFP_ATOMIC)) == NULL){
125		goto output;
126
127	}
128	x25_transmit_link(skbn, nb);
129
130	rc = 1;
131output:
132	x25_neigh_put(nb);
133out:
134	return rc;
135}
136
137void x25_clear_forward_by_lci(unsigned int lci)
138{
139	struct x25_forward *fwd;
140	struct list_head *entry, *tmp;
141
142	write_lock_bh(&x25_forward_list_lock);
143
144	list_for_each_safe(entry, tmp, &x25_forward_list) {
145		fwd = list_entry(entry, struct x25_forward, node);
146		if (fwd->lci == lci) {
147			list_del(&fwd->node);
148			kfree(fwd);
149		}
150	}
151	write_unlock_bh(&x25_forward_list_lock);
152}
153
154
155void x25_clear_forward_by_dev(struct net_device *dev)
156{
157	struct x25_forward *fwd;
158	struct list_head *entry, *tmp;
159
160	write_lock_bh(&x25_forward_list_lock);
161
162	list_for_each_safe(entry, tmp, &x25_forward_list) {
163		fwd = list_entry(entry, struct x25_forward, node);
164		if ((fwd->dev1 == dev) || (fwd->dev2 == dev)){
165			list_del(&fwd->node);
166			kfree(fwd);
167		}
168	}
169	write_unlock_bh(&x25_forward_list_lock);
170}
v3.1
  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 <linux/slab.h>
 14#include <net/x25.h>
 15
 16LIST_HEAD(x25_forward_list);
 17DEFINE_RWLOCK(x25_forward_list_lock);
 18
 19int x25_forward_call(struct x25_address *dest_addr, struct x25_neigh *from,
 20			struct sk_buff *skb, int lci)
 21{
 22	struct x25_route *rt;
 23	struct x25_neigh *neigh_new = NULL;
 24	struct list_head *entry;
 25	struct x25_forward *x25_frwd, *new_frwd;
 26	struct sk_buff *skbn;
 27	short same_lci = 0;
 28	int rc = 0;
 29
 30	if ((rt = x25_get_route(dest_addr)) == NULL)
 31		goto out_no_route;
 32
 33	if ((neigh_new = x25_get_neigh(rt->dev)) == NULL) {
 34		/* This shouldn't happen, if it occurs somehow
 35		 * do something sensible
 36		 */
 37		goto out_put_route;
 38	}
 39
 40	/* Avoid a loop. This is the normal exit path for a
 41	 * system with only one x.25 iface and default route
 42	 */
 43	if (rt->dev == from->dev) {
 44		goto out_put_nb;
 45	}
 46
 47	/* Remote end sending a call request on an already
 48	 * established LCI? It shouldn't happen, just in case..
 49	 */
 50	read_lock_bh(&x25_forward_list_lock);
 51	list_for_each(entry, &x25_forward_list) {
 52		x25_frwd = list_entry(entry, struct x25_forward, node);
 53		if (x25_frwd->lci == lci) {
 54			printk(KERN_WARNING "X.25: call request for lci which is already registered!, transmitting but not registering new pair\n");
 55			same_lci = 1;
 56		}
 57	}
 58	read_unlock_bh(&x25_forward_list_lock);
 59
 60	/* Save the forwarding details for future traffic */
 61	if (!same_lci){
 62		if ((new_frwd = kmalloc(sizeof(struct x25_forward),
 63						GFP_ATOMIC)) == NULL){
 64			rc = -ENOMEM;
 65			goto out_put_nb;
 66		}
 67		new_frwd->lci = lci;
 68		new_frwd->dev1 = rt->dev;
 69		new_frwd->dev2 = from->dev;
 70		write_lock_bh(&x25_forward_list_lock);
 71		list_add(&new_frwd->node, &x25_forward_list);
 72		write_unlock_bh(&x25_forward_list_lock);
 73	}
 74
 75	/* Forward the call request */
 76	if ( (skbn = skb_clone(skb, GFP_ATOMIC)) == NULL){
 77		goto out_put_nb;
 78	}
 79	x25_transmit_link(skbn, neigh_new);
 80	rc = 1;
 81
 82
 83out_put_nb:
 84	x25_neigh_put(neigh_new);
 85
 86out_put_route:
 87	x25_route_put(rt);
 88
 89out_no_route:
 90	return rc;
 91}
 92
 93
 94int x25_forward_data(int lci, struct x25_neigh *from, struct sk_buff *skb) {
 95
 96	struct x25_forward *frwd;
 97	struct list_head *entry;
 98	struct net_device *peer = NULL;
 99	struct x25_neigh *nb;
100	struct sk_buff *skbn;
101	int rc = 0;
102
103	read_lock_bh(&x25_forward_list_lock);
104	list_for_each(entry, &x25_forward_list) {
105		frwd = list_entry(entry, struct x25_forward, node);
106		if (frwd->lci == lci) {
107			/* The call is established, either side can send */
108			if (from->dev == frwd->dev1) {
109				peer = frwd->dev2;
110			} else {
111				peer = frwd->dev1;
112			}
113			break;
114		}
115	}
116	read_unlock_bh(&x25_forward_list_lock);
117
118	if ( (nb = x25_get_neigh(peer)) == NULL)
119		goto out;
120
121	if ( (skbn = pskb_copy(skb, GFP_ATOMIC)) == NULL){
122		goto output;
123
124	}
125	x25_transmit_link(skbn, nb);
126
127	rc = 1;
128output:
129	x25_neigh_put(nb);
130out:
131	return rc;
132}
133
134void x25_clear_forward_by_lci(unsigned int lci)
135{
136	struct x25_forward *fwd;
137	struct list_head *entry, *tmp;
138
139	write_lock_bh(&x25_forward_list_lock);
140
141	list_for_each_safe(entry, tmp, &x25_forward_list) {
142		fwd = list_entry(entry, struct x25_forward, node);
143		if (fwd->lci == lci) {
144			list_del(&fwd->node);
145			kfree(fwd);
146		}
147	}
148	write_unlock_bh(&x25_forward_list_lock);
149}
150
151
152void x25_clear_forward_by_dev(struct net_device *dev)
153{
154	struct x25_forward *fwd;
155	struct list_head *entry, *tmp;
156
157	write_lock_bh(&x25_forward_list_lock);
158
159	list_for_each_safe(entry, tmp, &x25_forward_list) {
160		fwd = list_entry(entry, struct x25_forward, node);
161		if ((fwd->dev1 == dev) || (fwd->dev2 == dev)){
162			list_del(&fwd->node);
163			kfree(fwd);
164		}
165	}
166	write_unlock_bh(&x25_forward_list_lock);
167}