xref: /openbmc/linux/net/bridge/br_vlan_tunnel.c (revision b7019ac5)
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(struct net_bridge_port *port, u16 vid, u32 tun_id)
93 {
94 	struct net_bridge_vlan_group *vg;
95 	struct net_bridge_vlan *vlan;
96 
97 	ASSERT_RTNL();
98 
99 	vg = nbp_vlan_group(port);
100 	vlan = br_vlan_find(vg, vid);
101 	if (!vlan)
102 		return -EINVAL;
103 
104 	return __vlan_tunnel_info_add(vg, vlan, tun_id);
105 }
106 
107 /* Must be protected by RTNL.
108  * Must be called with vid in range from 1 to 4094 inclusive.
109  */
110 int nbp_vlan_tunnel_info_delete(struct net_bridge_port *port, u16 vid)
111 {
112 	struct net_bridge_vlan_group *vg;
113 	struct net_bridge_vlan *v;
114 
115 	ASSERT_RTNL();
116 
117 	vg = nbp_vlan_group(port);
118 	v = br_vlan_find(vg, vid);
119 	if (!v)
120 		return -ENOENT;
121 
122 	vlan_tunnel_info_del(vg, v);
123 
124 	return 0;
125 }
126 
127 static void __vlan_tunnel_info_flush(struct net_bridge_vlan_group *vg)
128 {
129 	struct net_bridge_vlan *vlan, *tmp;
130 
131 	list_for_each_entry_safe(vlan, tmp, &vg->vlan_list, vlist)
132 		vlan_tunnel_info_del(vg, vlan);
133 }
134 
135 void nbp_vlan_tunnel_info_flush(struct net_bridge_port *port)
136 {
137 	struct net_bridge_vlan_group *vg;
138 
139 	ASSERT_RTNL();
140 
141 	vg = nbp_vlan_group(port);
142 	__vlan_tunnel_info_flush(vg);
143 }
144 
145 int vlan_tunnel_init(struct net_bridge_vlan_group *vg)
146 {
147 	return rhashtable_init(&vg->tunnel_hash, &br_vlan_tunnel_rht_params);
148 }
149 
150 void vlan_tunnel_deinit(struct net_bridge_vlan_group *vg)
151 {
152 	rhashtable_destroy(&vg->tunnel_hash);
153 }
154 
155 int br_handle_ingress_vlan_tunnel(struct sk_buff *skb,
156 				  struct net_bridge_port *p,
157 				  struct net_bridge_vlan_group *vg)
158 {
159 	struct ip_tunnel_info *tinfo = skb_tunnel_info(skb);
160 	struct net_bridge_vlan *vlan;
161 
162 	if (!vg || !tinfo)
163 		return 0;
164 
165 	/* if already tagged, ignore */
166 	if (skb_vlan_tagged(skb))
167 		return 0;
168 
169 	/* lookup vid, given tunnel id */
170 	vlan = br_vlan_tunnel_lookup(&vg->tunnel_hash, tinfo->key.tun_id);
171 	if (!vlan)
172 		return 0;
173 
174 	skb_dst_drop(skb);
175 
176 	__vlan_hwaccel_put_tag(skb, p->br->vlan_proto, vlan->vid);
177 
178 	return 0;
179 }
180 
181 int br_handle_egress_vlan_tunnel(struct sk_buff *skb,
182 				 struct net_bridge_vlan *vlan)
183 {
184 	int err;
185 
186 	if (!vlan || !vlan->tinfo.tunnel_id)
187 		return 0;
188 
189 	if (unlikely(!skb_vlan_tag_present(skb)))
190 		return 0;
191 
192 	skb_dst_drop(skb);
193 	err = skb_vlan_pop(skb);
194 	if (err)
195 		return err;
196 
197 	skb_dst_set(skb, dst_clone(&vlan->tinfo.tunnel_dst->dst));
198 
199 	return 0;
200 }
201