vlan: Add GVRP support

Add GVRP support for dynamically registering VLANs with switches.

By default GVRP is disabled because we only support the applicant-only
participant model, which means it should not be enabled on vlans that
are members of a bridge. Since there is currently no way to cleanly
determine that, the user is responsible for enabling it.

The code is pretty small and low impact, its wrapped in a config
option though because it depends on the GARP implementation and
the STP core.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 66 insertions, 0 deletions

diff --git a/net/8021q/vlan_gvrp.c b/net/8021q/vlan_gvrp.c
new file mode 100644
index 0000000..db97816
--- /dev/null
+++ b/net/8021q/vlan_gvrp.c
@@ -0,0 +1,66 @@
+/*
+ * 	IEEE 802.1Q GARP VLAN Registration Protocol (GVRP)
+ *
+ * 	Copyright (c) 2008 Patrick McHardy <kaber@trash.net>
+ *
+ *	This program is free software; you can redistribute it and/or
+ *	modify it under the terms of the GNU General Public License
+ *	version 2 as published by the Free Software Foundation.
+ */
+#include <linux/types.h>
+#include <linux/if_vlan.h>
+#include <net/garp.h>
+#include "vlan.h"
+
+#define GARP_GVRP_ADDRESS	{ 0x01, 0x80, 0xc2, 0x00, 0x00, 0x21 }
+
+enum gvrp_attributes {
+	GVRP_ATTR_INVALID,
+	GVRP_ATTR_VID,
+	__GVRP_ATTR_MAX
+};
+#define GVRP_ATTR_MAX	(__GVRP_ATTR_MAX - 1)
+
+static struct garp_application vlan_gvrp_app __read_mostly = {
+	.proto.group_address	= GARP_GVRP_ADDRESS,
+	.maxattr		= GVRP_ATTR_MAX,
+	.type			= GARP_APPLICATION_GVRP,
+};
+
+int vlan_gvrp_request_join(const struct net_device *dev)
+{
+	const struct vlan_dev_info *vlan = vlan_dev_info(dev);
+	__be16 vid = htons(vlan->vlan_id);
+
+	return garp_request_join(vlan->real_dev, &vlan_gvrp_app,
+				 &vid, sizeof(vid), GVRP_ATTR_VID);
+}
+
+void vlan_gvrp_request_leave(const struct net_device *dev)
+{
+	const struct vlan_dev_info *vlan = vlan_dev_info(dev);
+	__be16 vid = htons(vlan->vlan_id);
+
+	garp_request_leave(vlan->real_dev, &vlan_gvrp_app,
+			   &vid, sizeof(vid), GVRP_ATTR_VID);
+}
+
+int vlan_gvrp_init_applicant(struct net_device *dev)
+{
+	return garp_init_applicant(dev, &vlan_gvrp_app);
+}
+
+void vlan_gvrp_uninit_applicant(struct net_device *dev)
+{
+	garp_uninit_applicant(dev, &vlan_gvrp_app);
+}
+
+int __init vlan_gvrp_init(void)
+{
+	return garp_register_application(&vlan_gvrp_app);
+}
+
+void vlan_gvrp_uninit(void)
+{
+	garp_unregister_application(&vlan_gvrp_app);
+}