blob: d339e0c810a820096dd6c040245d5256fe5065f1 [file] [log] [blame]
Andrew Hendry95a9dc42007-02-08 13:34:02 -08001/*
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
15struct list_head x25_forward_list = LIST_HEAD_INIT(x25_forward_list);
16DEFINE_RWLOCK(x25_forward_list_lock);
17
18int 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
29 if ((rt = x25_get_route(dest_addr)) != NULL) {
30
31 if ((neigh_new = x25_get_neigh(rt->dev)) == NULL) {
32 /* This shouldnt happen, if it occurs somehow
33 * do something sensible
34 */
35 goto out_put_route;
36 }
37
38 /* Avoid a loop. This is the normal exit path for a
39 * system with only one x.25 iface and default route
40 */
41 if (rt->dev == from->dev) {
42 goto out_put_nb;
43 }
44
45 /* Remote end sending a call request on an already
46 * established LCI? It shouldnt happen, just in case..
47 */
48 read_lock_bh(&x25_forward_list_lock);
49 list_for_each(entry, &x25_forward_list) {
50 x25_frwd = list_entry(entry, struct x25_forward, node);
51 if (x25_frwd->lci == lci) {
52 printk(KERN_WARNING "X.25: call request for lci which is already registered!, transmitting but not registering new pair\n");
53 same_lci = 1;
54 }
55 }
56 read_unlock_bh(&x25_forward_list_lock);
57
58 /* Save the forwarding details for future traffic */
59 if (!same_lci){
60 if ((new_frwd = kmalloc(sizeof(struct x25_forward),
61 GFP_ATOMIC)) == NULL){
62 rc = -ENOMEM;
63 goto out_put_nb;
64 }
65 new_frwd->lci = lci;
66 new_frwd->dev1 = rt->dev;
67 new_frwd->dev2 = from->dev;
68 write_lock_bh(&x25_forward_list_lock);
69 list_add(&new_frwd->node, &x25_forward_list);
70 write_unlock_bh(&x25_forward_list_lock);
71 }
72
73 /* Forward the call request */
74 if ( (skbn = skb_clone(skb, GFP_ATOMIC)) == NULL){
75 goto out_put_nb;
76 }
77 x25_transmit_link(skbn, neigh_new);
78 rc = 1;
79 }
80
81
82out_put_nb:
83 x25_neigh_put(neigh_new);
84
85out_put_route:
86 x25_route_put(rt);
87 return rc;
88}
89
90
91int x25_forward_data(int lci, struct x25_neigh *from, struct sk_buff *skb) {
92
93 struct x25_forward *frwd;
94 struct list_head *entry;
95 struct net_device *peer = NULL;
96 struct x25_neigh *nb;
97 struct sk_buff *skbn;
98 int rc = 0;
99
100 read_lock_bh(&x25_forward_list_lock);
101 list_for_each(entry, &x25_forward_list) {
102 frwd = list_entry(entry, struct x25_forward, node);
103 if (frwd->lci == lci) {
104 /* The call is established, either side can send */
105 if (from->dev == frwd->dev1) {
106 peer = frwd->dev2;
107 } else {
108 peer = frwd->dev1;
109 }
110 break;
111 }
112 }
113 read_unlock_bh(&x25_forward_list_lock);
114
115 if ( (nb = x25_get_neigh(peer)) == NULL)
116 goto out;
117
118 if ( (skbn = pskb_copy(skb, GFP_ATOMIC)) == NULL){
119 goto out;
120
121 }
122 x25_transmit_link(skbn, nb);
123
124 x25_neigh_put(nb);
125 rc = 1;
126out:
127 return rc;
128}
129
130void x25_clear_forward_by_lci(unsigned int lci)
131{
132 struct x25_forward *fwd;
133 struct list_head *entry, *tmp;
134
135 write_lock_bh(&x25_forward_list_lock);
136
137 list_for_each_safe(entry, tmp, &x25_forward_list) {
138 fwd = list_entry(entry, struct x25_forward, node);
139 if (fwd->lci == lci) {
140 list_del(&fwd->node);
141 kfree(fwd);
142 }
143 }
144 write_unlock_bh(&x25_forward_list_lock);
145}
146
147
148void x25_clear_forward_by_dev(struct net_device *dev)
149{
150 struct x25_forward *fwd;
151 struct list_head *entry, *tmp;
152
153 write_lock_bh(&x25_forward_list_lock);
154
155 list_for_each_safe(entry, tmp, &x25_forward_list) {
156 fwd = list_entry(entry, struct x25_forward, node);
157 if ((fwd->dev1 == dev) || (fwd->dev2 == dev)){
158 list_del(&fwd->node);
159 kfree(fwd);
160 }
161 }
162 write_unlock_bh(&x25_forward_list_lock);
163}