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Diffstat (limited to 'net/x25/x25_forward.c')
-rw-r--r--net/x25/x25_forward.c170
1 files changed, 170 insertions, 0 deletions
diff --git a/net/x25/x25_forward.c b/net/x25/x25_forward.c
new file mode 100644
index 000000000..cf561f161
--- /dev/null
+++ b/net/x25/x25_forward.c
@@ -0,0 +1,170 @@
+/*
+ * 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
+ */
+
+#define pr_fmt(fmt) "X25: " fmt
+
+#include <linux/if_arp.h>
+#include <linux/init.h>
+#include <linux/slab.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 shouldn't 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 shouldn't 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) {
+ pr_warn("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);
+}