1 files changed, 100 insertions, 0 deletions
diff --git a/arch/um/os-Linux/drivers/ethertap_kern.c b/arch/um/os-Linux/drivers/ethertap_kern.c
new file mode 100644
index 000000000..3182e759d
--- /dev/null
+++ b/arch/um/os-Linux/drivers/ethertap_kern.c
@@ -0,0 +1,100 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2001 Lennert Buytenhek (buytenh@gnu.org) and
+ * James Leu (jleu@mindspring.net).
+ * Copyright (C) 2001 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
+ * Copyright (C) 2001 by various other people who didn't put their name here.
+ */
+
+#include <linux/init.h>
+#include <linux/netdevice.h>
+#include "etap.h"
+#include <net_kern.h>
+
+struct ethertap_init {
+	char *dev_name;
+	char *gate_addr;
+};
+
+static void etap_init(struct net_device *dev, void *data)
+{
+	struct uml_net_private *pri;
+	struct ethertap_data *epri;
+	struct ethertap_init *init = data;
+
+	pri = netdev_priv(dev);
+	epri = (struct ethertap_data *) pri->user;
+	epri->dev_name = init->dev_name;
+	epri->gate_addr = init->gate_addr;
+	epri->data_fd = -1;
+	epri->control_fd = -1;
+	epri->dev = dev;
+
+	printk(KERN_INFO "ethertap backend - %s", epri->dev_name);
+	if (epri->gate_addr != NULL)
+		printk(KERN_CONT ", IP = %s", epri->gate_addr);
+	printk(KERN_CONT "\n");
+}
+
+static int etap_read(int fd, struct sk_buff *skb, struct uml_net_private *lp)
+{
+	int len;
+
+	len = net_recvfrom(fd, skb_mac_header(skb),
+			   skb->dev->mtu + 2 + ETH_HEADER_ETHERTAP);
+	if (len <= 0)
+		return(len);
+
+	skb_pull(skb, 2);
+	len -= 2;
+	return len;
+}
+
+static int etap_write(int fd, struct sk_buff *skb, struct uml_net_private *lp)
+{
+	skb_push(skb, 2);
+	return net_send(fd, skb->data, skb->len);
+}
+
+const struct net_kern_info ethertap_kern_info = {
+	.init			= etap_init,
+	.protocol		= eth_protocol,
+	.read			= etap_read,
+	.write 			= etap_write,
+};
+
+int ethertap_setup(char *str, char **mac_out, void *data)
+{
+	struct ethertap_init *init = data;
+
+	*init = ((struct ethertap_init)
+		{ .dev_name 	= NULL,
+		  .gate_addr 	= NULL });
+	if (tap_setup_common(str, "ethertap", &init->dev_name, mac_out,
+			    &init->gate_addr))
+		return 0;
+	if (init->dev_name == NULL) {
+		printk(KERN_ERR "ethertap_setup : Missing tap device name\n");
+		return 0;
+	}
+
+	return 1;
+}
+
+static struct transport ethertap_transport = {
+	.list 		= LIST_HEAD_INIT(ethertap_transport.list),
+	.name 		= "ethertap",
+	.setup  	= ethertap_setup,
+	.user 		= &ethertap_user_info,
+	.kern 		= &ethertap_kern_info,
+	.private_size 	= sizeof(struct ethertap_data),
+	.setup_size 	= sizeof(struct ethertap_init),
+};
+
+static int register_ethertap(void)
+{
+	register_transport(&ethertap_transport);
+	return 0;
+}
+
+late_initcall(register_ethertap);