1 files changed, 73 insertions, 0 deletions
diff --git a/net/netrom/nr_loopback.c b/net/netrom/nr_loopback.c
new file mode 100644
index 000000000..511819fbf
--- /dev/null
+++ b/net/netrom/nr_loopback.c
@@ -0,0 +1,73 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *
+ * Copyright Tomi Manninen OH2BNS (oh2bns@sral.fi)
+ */
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/socket.h>
+#include <linux/timer.h>
+#include <net/ax25.h>
+#include <linux/skbuff.h>
+#include <net/netrom.h>
+#include <linux/init.h>
+
+static void nr_loopback_timer(struct timer_list *);
+
+static struct sk_buff_head loopback_queue;
+static DEFINE_TIMER(loopback_timer, nr_loopback_timer);
+
+void __init nr_loopback_init(void)
+{
+	skb_queue_head_init(&loopback_queue);
+}
+
+static inline int nr_loopback_running(void)
+{
+	return timer_pending(&loopback_timer);
+}
+
+int nr_loopback_queue(struct sk_buff *skb)
+{
+	struct sk_buff *skbn;
+
+	if ((skbn = alloc_skb(skb->len, GFP_ATOMIC)) != NULL) {
+		skb_copy_from_linear_data(skb, skb_put(skbn, skb->len), skb->len);
+		skb_reset_transport_header(skbn);
+
+		skb_queue_tail(&loopback_queue, skbn);
+
+		if (!nr_loopback_running())
+			mod_timer(&loopback_timer, jiffies + 10);
+	}
+
+	kfree_skb(skb);
+	return 1;
+}
+
+static void nr_loopback_timer(struct timer_list *unused)
+{
+	struct sk_buff *skb;
+	ax25_address *nr_dest;
+	struct net_device *dev;
+
+	if ((skb = skb_dequeue(&loopback_queue)) != NULL) {
+		nr_dest = (ax25_address *)(skb->data + 7);
+
+		dev = nr_dev_get(nr_dest);
+
+		if (dev == NULL || nr_rx_frame(skb, dev) == 0)
+			kfree_skb(skb);
+
+		dev_put(dev);
+
+		if (!skb_queue_empty(&loopback_queue) && !nr_loopback_running())
+			mod_timer(&loopback_timer, jiffies + 10);
+	}
+}
+
+void nr_loopback_clear(void)
+{
+	del_timer_sync(&loopback_timer);
+	skb_queue_purge(&loopback_queue);
+}