xref: /openbmc/linux/net/bridge/br_vlan_tunnel.c (revision cb1aaebe)
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 
23 static 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 
32 static 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 	.obj_cmpfn = br_vlan_tunid_cmp,
38 	.automatic_shrinking = true,
39 };
40 
41 static struct net_bridge_vlan *br_vlan_tunnel_lookup(struct rhashtable *tbl,
42 						     u64 tunnel_id)
43 {
44 	return rhashtable_lookup_fast(tbl, &tunnel_id,
45 				      br_vlan_tunnel_rht_params);
46 }
47 
48 void vlan_tunnel_info_del(struct net_bridge_vlan_group *vg,
49 			  struct net_bridge_vlan *vlan)
50 {
51 	if (!vlan->tinfo.tunnel_dst)
52 		return;
53 	rhashtable_remove_fast(&vg->tunnel_hash, &vlan->tnode,
54 			       br_vlan_tunnel_rht_params);
55 	vlan->tinfo.tunnel_id = 0;
56 	dst_release(&vlan->tinfo.tunnel_dst->dst);
57 	vlan->tinfo.tunnel_dst = NULL;
58 }
59 
60 static int __vlan_tunnel_info_add(struct net_bridge_vlan_group *vg,
61 				  struct net_bridge_vlan *vlan, u32 tun_id)
62 {
63 	struct metadata_dst *metadata = NULL;
64 	__be64 key = key32_to_tunnel_id(cpu_to_be32(tun_id));
65 	int err;
66 
67 	if (vlan->tinfo.tunnel_dst)
68 		return -EEXIST;
69 
70 	metadata = __ip_tun_set_dst(0, 0, 0, 0, 0, TUNNEL_KEY,
71 				    key, 0);
72 	if (!metadata)
73 		return -EINVAL;
74 
75 	metadata->u.tun_info.mode |= IP_TUNNEL_INFO_TX | IP_TUNNEL_INFO_BRIDGE;
76 	vlan->tinfo.tunnel_dst = metadata;
77 	vlan->tinfo.tunnel_id = key;
78 
79 	err = rhashtable_lookup_insert_fast(&vg->tunnel_hash, &vlan->tnode,
80 					    br_vlan_tunnel_rht_params);
81 	if (err)
82 		goto out;
83 
84 	return 0;
85 out:
86 	dst_release(&vlan->tinfo.tunnel_dst->dst);
87 	vlan->tinfo.tunnel_dst = NULL;
88 	vlan->tinfo.tunnel_id = 0;
89 
90 	return err;
91 }
92 
93 /* Must be protected by RTNL.
94  * Must be called with vid in range from 1 to 4094 inclusive.
95  */
96 int nbp_vlan_tunnel_info_add(struct net_bridge_port *port, u16 vid, u32 tun_id)
97 {
98 	struct net_bridge_vlan_group *vg;
99 	struct net_bridge_vlan *vlan;
100 
101 	ASSERT_RTNL();
102 
103 	vg = nbp_vlan_group(port);
104 	vlan = br_vlan_find(vg, vid);
105 	if (!vlan)
106 		return -EINVAL;
107 
108 	return __vlan_tunnel_info_add(vg, vlan, tun_id);
109 }
110 
111 /* Must be protected by RTNL.
112  * Must be called with vid in range from 1 to 4094 inclusive.
113  */
114 int nbp_vlan_tunnel_info_delete(struct net_bridge_port *port, u16 vid)
115 {
116 	struct net_bridge_vlan_group *vg;
117 	struct net_bridge_vlan *v;
118 
119 	ASSERT_RTNL();
120 
121 	vg = nbp_vlan_group(port);
122 	v = br_vlan_find(vg, vid);
123 	if (!v)
124 		return -ENOENT;
125 
126 	vlan_tunnel_info_del(vg, v);
127 
128 	return 0;
129 }
130 
131 static void __vlan_tunnel_info_flush(struct net_bridge_vlan_group *vg)
132 {
133 	struct net_bridge_vlan *vlan, *tmp;
134 
135 	list_for_each_entry_safe(vlan, tmp, &vg->vlan_list, vlist)
136 		vlan_tunnel_info_del(vg, vlan);
137 }
138 
139 void nbp_vlan_tunnel_info_flush(struct net_bridge_port *port)
140 {
141 	struct net_bridge_vlan_group *vg;
142 
143 	ASSERT_RTNL();
144 
145 	vg = nbp_vlan_group(port);
146 	__vlan_tunnel_info_flush(vg);
147 }
148 
149 int vlan_tunnel_init(struct net_bridge_vlan_group *vg)
150 {
151 	return rhashtable_init(&vg->tunnel_hash, &br_vlan_tunnel_rht_params);
152 }
153 
154 void vlan_tunnel_deinit(struct net_bridge_vlan_group *vg)
155 {
156 	rhashtable_destroy(&vg->tunnel_hash);
157 }
158 
159 int br_handle_ingress_vlan_tunnel(struct sk_buff *skb,
160 				  struct net_bridge_port *p,
161 				  struct net_bridge_vlan_group *vg)
162 {
163 	struct ip_tunnel_info *tinfo = skb_tunnel_info(skb);
164 	struct net_bridge_vlan *vlan;
165 
166 	if (!vg || !tinfo)
167 		return 0;
168 
169 	/* if already tagged, ignore */
170 	if (skb_vlan_tagged(skb))
171 		return 0;
172 
173 	/* lookup vid, given tunnel id */
174 	vlan = br_vlan_tunnel_lookup(&vg->tunnel_hash, tinfo->key.tun_id);
175 	if (!vlan)
176 		return 0;
177 
178 	skb_dst_drop(skb);
179 
180 	__vlan_hwaccel_put_tag(skb, p->br->vlan_proto, vlan->vid);
181 
182 	return 0;
183 }
184 
185 int br_handle_egress_vlan_tunnel(struct sk_buff *skb,
186 				 struct net_bridge_vlan *vlan)
187 {
188 	int err;
189 
190 	if (!vlan || !vlan->tinfo.tunnel_id)
191 		return 0;
192 
193 	if (unlikely(!skb_vlan_tag_present(skb)))
194 		return 0;
195 
196 	skb_dst_drop(skb);
197 	err = skb_vlan_pop(skb);
198 	if (err)
199 		return err;
200 
201 	skb_dst_set(skb, dst_clone(&vlan->tinfo.tunnel_dst->dst));
202 
203 	return 0;
204 }
205