1 files changed, 163 insertions, 0 deletions

diff --git a/net/x25/x25_forward.c b/net/x25/x25_forward.c
new file mode 100644
index 000000000000..d339e0c810a8
--- /dev/null
+++ b/net/x25/x25_forward.c
@@ -0,0 +1,163 @@
+/*
+ *      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>
+
+struct list_head x25_forward_list = LIST_HEAD_INIT(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) {
+
+                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);
+        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 out;
+
+        }
+        x25_transmit_link(skbn, nb);
+
+        x25_neigh_put(nb);
+        rc = 1;
+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);
+}