Adding upstream version 5.10.209.upstream/5.10.209upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 161 insertions, 0 deletions

diff --git a/net/x25/x25_forward.c b/net/x25/x25_forward.c
new file mode 100644
index 000000000..d48ad6d29
--- /dev/null
+++ b/net/x25/x25_forward.c
@@ -0,0 +1,161 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *	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, *tmp;
+
+	write_lock_bh(&x25_forward_list_lock);
+
+	list_for_each_entry_safe(fwd, tmp, &x25_forward_list, 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, *tmp;
+
+	write_lock_bh(&x25_forward_list_lock);
+
+	list_for_each_entry_safe(fwd, tmp, &x25_forward_list, node) {
+		if ((fwd->dev1 == dev) || (fwd->dev2 == dev)){
+			list_del(&fwd->node);
+			kfree(fwd);
+		}
+	}
+	write_unlock_bh(&x25_forward_list_lock);
+}