1/*
  2 *	Bridge per vlan tunnel port dst_metadata handling code
  3 *
  4 *	Authors:
  5 *	Roopa Prabhu		<roopa@cumulusnetworks.com>
  6 *
  7 *	This program is free software; you can redistribute it and/or
  8 *	modify it under the terms of the GNU General Public License
  9 *	as published by the Free Software Foundation; either version
 10 *	2 of the License, or (at your option) any later version.
 11 */
 12
 13#include <linux/kernel.h>
 14#include <linux/netdevice.h>
 15#include <linux/rtnetlink.h>
 16#include <linux/slab.h>
 17#include <net/switchdev.h>
 18#include <net/dst_metadata.h>
 19
 20#include "br_private.h"
 21#include "br_private_tunnel.h"
 22
 23static inline int br_vlan_tunid_cmp(struct rhashtable_compare_arg *arg,
 24				    const void *ptr)
 25{
 26	const struct net_bridge_vlan *vle = ptr;
 27	__be64 tunid = *(__be64 *)arg->key;
 28
 29	return vle->tinfo.tunnel_id != tunid;
 30}
 31
 32static const struct rhashtable_params br_vlan_tunnel_rht_params = {
 33	.head_offset = offsetof(struct net_bridge_vlan, tnode),
 34	.key_offset = offsetof(struct net_bridge_vlan, tinfo.tunnel_id),
 35	.key_len = sizeof(__be64),
 36	.nelem_hint = 3,
 37	.locks_mul = 1,
 38	.obj_cmpfn = br_vlan_tunid_cmp,
 39	.automatic_shrinking = true,
 40};
 41
 42static struct net_bridge_vlan *br_vlan_tunnel_lookup(struct rhashtable *tbl,
 43						     u64 tunnel_id)
 44{
 45	return rhashtable_lookup_fast(tbl, &tunnel_id,
 46				      br_vlan_tunnel_rht_params);
 47}
 48
 49void vlan_tunnel_info_del(struct net_bridge_vlan_group *vg,
 50			  struct net_bridge_vlan *vlan)
 51{
 52	if (!vlan->tinfo.tunnel_dst)
 53		return;
 54	rhashtable_remove_fast(&vg->tunnel_hash, &vlan->tnode,
 55			       br_vlan_tunnel_rht_params);
 56	vlan->tinfo.tunnel_id = 0;
 57	dst_release(&vlan->tinfo.tunnel_dst->dst);
 58	vlan->tinfo.tunnel_dst = NULL;
 59}
 60
 61static int __vlan_tunnel_info_add(struct net_bridge_vlan_group *vg,
 62				  struct net_bridge_vlan *vlan, u32 tun_id)
 63{
 64	struct metadata_dst *metadata = NULL;
 65	__be64 key = key32_to_tunnel_id(cpu_to_be32(tun_id));
 66	int err;
 67
 68	if (vlan->tinfo.tunnel_dst)
 69		return -EEXIST;
 70
 71	metadata = __ip_tun_set_dst(0, 0, 0, 0, 0, TUNNEL_KEY,
 72				    key, 0);
 73	if (!metadata)
 74		return -EINVAL;
 75
 76	metadata->u.tun_info.mode |= IP_TUNNEL_INFO_TX | IP_TUNNEL_INFO_BRIDGE;
 77	vlan->tinfo.tunnel_dst = metadata;
 78	vlan->tinfo.tunnel_id = key;
 79
 80	err = rhashtable_lookup_insert_fast(&vg->tunnel_hash, &vlan->tnode,
 81					    br_vlan_tunnel_rht_params);
 82	if (err)
 83		goto out;
 84
 85	return 0;
 86out:
 87	dst_release(&vlan->tinfo.tunnel_dst->dst);
 88	vlan->tinfo.tunnel_dst = NULL;
 89	vlan->tinfo.tunnel_id = 0;
 90
 91	return err;
 92}
 93
 94/* Must be protected by RTNL.
 95 * Must be called with vid in range from 1 to 4094 inclusive.
 96 */
 97int nbp_vlan_tunnel_info_add(struct net_bridge_port *port, u16 vid, u32 tun_id)
 98{
 99	struct net_bridge_vlan_group *vg;
100	struct net_bridge_vlan *vlan;
101
102	ASSERT_RTNL();
103
104	vg = nbp_vlan_group(port);
105	vlan = br_vlan_find(vg, vid);
106	if (!vlan)
107		return -EINVAL;
108
109	return __vlan_tunnel_info_add(vg, vlan, tun_id);
110}
111
112/* Must be protected by RTNL.
113 * Must be called with vid in range from 1 to 4094 inclusive.
114 */
115int nbp_vlan_tunnel_info_delete(struct net_bridge_port *port, u16 vid)
116{
117	struct net_bridge_vlan_group *vg;
118	struct net_bridge_vlan *v;
119
120	ASSERT_RTNL();
121
122	vg = nbp_vlan_group(port);
123	v = br_vlan_find(vg, vid);
124	if (!v)
125		return -ENOENT;
126
127	vlan_tunnel_info_del(vg, v);
128
129	return 0;
130}
131
132static void __vlan_tunnel_info_flush(struct net_bridge_vlan_group *vg)
133{
134	struct net_bridge_vlan *vlan, *tmp;
135
136	list_for_each_entry_safe(vlan, tmp, &vg->vlan_list, vlist)
137		vlan_tunnel_info_del(vg, vlan);
138}
139
140void nbp_vlan_tunnel_info_flush(struct net_bridge_port *port)
141{
142	struct net_bridge_vlan_group *vg;
143
144	ASSERT_RTNL();
145
146	vg = nbp_vlan_group(port);
147	__vlan_tunnel_info_flush(vg);
148}
149
150int vlan_tunnel_init(struct net_bridge_vlan_group *vg)
151{
152	return rhashtable_init(&vg->tunnel_hash, &br_vlan_tunnel_rht_params);
153}
154
155void vlan_tunnel_deinit(struct net_bridge_vlan_group *vg)
156{
157	rhashtable_destroy(&vg->tunnel_hash);
158}
159
160int br_handle_ingress_vlan_tunnel(struct sk_buff *skb,
161				  struct net_bridge_port *p,
162				  struct net_bridge_vlan_group *vg)
163{
164	struct ip_tunnel_info *tinfo = skb_tunnel_info(skb);
165	struct net_bridge_vlan *vlan;
166
167	if (!vg || !tinfo)
168		return 0;
169
170	/* if already tagged, ignore */
171	if (skb_vlan_tagged(skb))
172		return 0;
173
174	/* lookup vid, given tunnel id */
175	vlan = br_vlan_tunnel_lookup(&vg->tunnel_hash, tinfo->key.tun_id);
176	if (!vlan)
177		return 0;
178
179	skb_dst_drop(skb);
180
181	__vlan_hwaccel_put_tag(skb, p->br->vlan_proto, vlan->vid);
182
183	return 0;
184}
185
186int br_handle_egress_vlan_tunnel(struct sk_buff *skb,
187				 struct net_bridge_vlan *vlan)
188{
189	int err;
190
191	if (!vlan || !vlan->tinfo.tunnel_id)
192		return 0;
193
194	if (unlikely(!skb_vlan_tag_present(skb)))
195		return 0;
196
197	skb_dst_drop(skb);
198	err = skb_vlan_pop(skb);
199	if (err)
200		return err;
201
202	skb_dst_set(skb, dst_clone(&vlan->tinfo.tunnel_dst->dst));
203
204	return 0;
205}