xref: /linux/net/bridge/br_vlan_tunnel.c (revision ca64d84e93762f4e587e040a44ad9f6089afc777)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *	Bridge per vlan tunnel port dst_metadata handling code
4  *
5  *	Authors:
6  *	Roopa Prabhu		<roopa@cumulusnetworks.com>
7  */
8 
9 #include <linux/kernel.h>
10 #include <linux/netdevice.h>
11 #include <linux/rtnetlink.h>
12 #include <linux/slab.h>
13 #include <net/switchdev.h>
14 #include <net/dst_metadata.h>
15 
16 #include "br_private.h"
17 #include "br_private_tunnel.h"
18 
19 static inline int br_vlan_tunid_cmp(struct rhashtable_compare_arg *arg,
20 				    const void *ptr)
21 {
22 	const struct net_bridge_vlan *vle = ptr;
23 	__be64 tunid = *(__be64 *)arg->key;
24 
25 	return vle->tinfo.tunnel_id != tunid;
26 }
27 
28 static const struct rhashtable_params br_vlan_tunnel_rht_params = {
29 	.head_offset = offsetof(struct net_bridge_vlan, tnode),
30 	.key_offset = offsetof(struct net_bridge_vlan, tinfo.tunnel_id),
31 	.key_len = sizeof(__be64),
32 	.nelem_hint = 3,
33 	.obj_cmpfn = br_vlan_tunid_cmp,
34 	.automatic_shrinking = true,
35 };
36 
37 static struct net_bridge_vlan *br_vlan_tunnel_lookup(struct rhashtable *tbl,
38 						     u64 tunnel_id)
39 {
40 	return rhashtable_lookup_fast(tbl, &tunnel_id,
41 				      br_vlan_tunnel_rht_params);
42 }
43 
44 void vlan_tunnel_info_del(struct net_bridge_vlan_group *vg,
45 			  struct net_bridge_vlan *vlan)
46 {
47 	if (!vlan->tinfo.tunnel_dst)
48 		return;
49 	rhashtable_remove_fast(&vg->tunnel_hash, &vlan->tnode,
50 			       br_vlan_tunnel_rht_params);
51 	vlan->tinfo.tunnel_id = 0;
52 	dst_release(&vlan->tinfo.tunnel_dst->dst);
53 	vlan->tinfo.tunnel_dst = NULL;
54 }
55 
56 static int __vlan_tunnel_info_add(struct net_bridge_vlan_group *vg,
57 				  struct net_bridge_vlan *vlan, u32 tun_id)
58 {
59 	struct metadata_dst *metadata = NULL;
60 	__be64 key = key32_to_tunnel_id(cpu_to_be32(tun_id));
61 	int err;
62 
63 	if (vlan->tinfo.tunnel_dst)
64 		return -EEXIST;
65 
66 	metadata = __ip_tun_set_dst(0, 0, 0, 0, 0, TUNNEL_KEY,
67 				    key, 0);
68 	if (!metadata)
69 		return -EINVAL;
70 
71 	metadata->u.tun_info.mode |= IP_TUNNEL_INFO_TX | IP_TUNNEL_INFO_BRIDGE;
72 	vlan->tinfo.tunnel_dst = metadata;
73 	vlan->tinfo.tunnel_id = key;
74 
75 	err = rhashtable_lookup_insert_fast(&vg->tunnel_hash, &vlan->tnode,
76 					    br_vlan_tunnel_rht_params);
77 	if (err)
78 		goto out;
79 
80 	return 0;
81 out:
82 	dst_release(&vlan->tinfo.tunnel_dst->dst);
83 	vlan->tinfo.tunnel_dst = NULL;
84 	vlan->tinfo.tunnel_id = 0;
85 
86 	return err;
87 }
88 
89 /* Must be protected by RTNL.
90  * Must be called with vid in range from 1 to 4094 inclusive.
91  */
92 int nbp_vlan_tunnel_info_add(const struct net_bridge_port *port, u16 vid,
93 			     u32 tun_id)
94 {
95 	struct net_bridge_vlan_group *vg;
96 	struct net_bridge_vlan *vlan;
97 
98 	ASSERT_RTNL();
99 
100 	vg = nbp_vlan_group(port);
101 	vlan = br_vlan_find(vg, vid);
102 	if (!vlan)
103 		return -EINVAL;
104 
105 	return __vlan_tunnel_info_add(vg, vlan, tun_id);
106 }
107 
108 /* Must be protected by RTNL.
109  * Must be called with vid in range from 1 to 4094 inclusive.
110  */
111 int nbp_vlan_tunnel_info_delete(const struct net_bridge_port *port, u16 vid)
112 {
113 	struct net_bridge_vlan_group *vg;
114 	struct net_bridge_vlan *v;
115 
116 	ASSERT_RTNL();
117 
118 	vg = nbp_vlan_group(port);
119 	v = br_vlan_find(vg, vid);
120 	if (!v)
121 		return -ENOENT;
122 
123 	vlan_tunnel_info_del(vg, v);
124 
125 	return 0;
126 }
127 
128 static void __vlan_tunnel_info_flush(struct net_bridge_vlan_group *vg)
129 {
130 	struct net_bridge_vlan *vlan, *tmp;
131 
132 	list_for_each_entry_safe(vlan, tmp, &vg->vlan_list, vlist)
133 		vlan_tunnel_info_del(vg, vlan);
134 }
135 
136 void nbp_vlan_tunnel_info_flush(struct net_bridge_port *port)
137 {
138 	struct net_bridge_vlan_group *vg;
139 
140 	ASSERT_RTNL();
141 
142 	vg = nbp_vlan_group(port);
143 	__vlan_tunnel_info_flush(vg);
144 }
145 
146 int vlan_tunnel_init(struct net_bridge_vlan_group *vg)
147 {
148 	return rhashtable_init(&vg->tunnel_hash, &br_vlan_tunnel_rht_params);
149 }
150 
151 void vlan_tunnel_deinit(struct net_bridge_vlan_group *vg)
152 {
153 	rhashtable_destroy(&vg->tunnel_hash);
154 }
155 
156 int br_handle_ingress_vlan_tunnel(struct sk_buff *skb,
157 				  struct net_bridge_port *p,
158 				  struct net_bridge_vlan_group *vg)
159 {
160 	struct ip_tunnel_info *tinfo = skb_tunnel_info(skb);
161 	struct net_bridge_vlan *vlan;
162 
163 	if (!vg || !tinfo)
164 		return 0;
165 
166 	/* if already tagged, ignore */
167 	if (skb_vlan_tagged(skb))
168 		return 0;
169 
170 	/* lookup vid, given tunnel id */
171 	vlan = br_vlan_tunnel_lookup(&vg->tunnel_hash, tinfo->key.tun_id);
172 	if (!vlan)
173 		return 0;
174 
175 	skb_dst_drop(skb);
176 
177 	__vlan_hwaccel_put_tag(skb, p->br->vlan_proto, vlan->vid);
178 
179 	return 0;
180 }
181 
182 int br_handle_egress_vlan_tunnel(struct sk_buff *skb,
183 				 struct net_bridge_vlan *vlan)
184 {
185 	int err;
186 
187 	if (!vlan || !vlan->tinfo.tunnel_id)
188 		return 0;
189 
190 	if (unlikely(!skb_vlan_tag_present(skb)))
191 		return 0;
192 
193 	skb_dst_drop(skb);
194 	err = skb_vlan_pop(skb);
195 	if (err)
196 		return err;
197 
198 	skb_dst_set(skb, dst_clone(&vlan->tinfo.tunnel_dst->dst));
199 
200 	return 0;
201 }
202