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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 <[email protected]>
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
19static 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
28static 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
37static struct net_bridge_vlan *br_vlan_tunnel_lookup(struct rhashtable *tbl,
38 __be64 tunnel_id)
39{
40 return rhashtable_lookup_fast(tbl, &tunnel_id,
41 br_vlan_tunnel_rht_params);
42}
43
44static void vlan_tunnel_info_release(struct net_bridge_vlan *vlan)
45{
46 struct metadata_dst *tdst = rtnl_dereference(vlan->tinfo.tunnel_dst);
47
48 WRITE_ONCE(vlan->tinfo.tunnel_id, 0);
49 RCU_INIT_POINTER(vlan->tinfo.tunnel_dst, NULL);
50 dst_release(&tdst->dst);
51}
52
53void vlan_tunnel_info_del(struct net_bridge_vlan_group *vg,
54 struct net_bridge_vlan *vlan)
55{
56 if (!rcu_access_pointer(vlan->tinfo.tunnel_dst))
57 return;
58 rhashtable_remove_fast(&vg->tunnel_hash, &vlan->tnode,
59 br_vlan_tunnel_rht_params);
60 vlan_tunnel_info_release(vlan);
61}
62
63static int __vlan_tunnel_info_add(struct net_bridge_vlan_group *vg,
64 struct net_bridge_vlan *vlan, u32 tun_id)
65{
66 struct metadata_dst *metadata = rtnl_dereference(vlan->tinfo.tunnel_dst);
67 __be64 key = key32_to_tunnel_id(cpu_to_be32(tun_id));
68 IP_TUNNEL_DECLARE_FLAGS(flags) = { };
69 int err;
70
71 if (metadata)
72 return -EEXIST;
73
74 __set_bit(IP_TUNNEL_KEY_BIT, flags);
75 metadata = __ip_tun_set_dst(0, 0, 0, 0, 0, flags, key, 0);
76 if (!metadata)
77 return -EINVAL;
78
79 metadata->u.tun_info.mode |= IP_TUNNEL_INFO_TX | IP_TUNNEL_INFO_BRIDGE;
80 rcu_assign_pointer(vlan->tinfo.tunnel_dst, metadata);
81 WRITE_ONCE(vlan->tinfo.tunnel_id, key);
82
83 err = rhashtable_lookup_insert_fast(&vg->tunnel_hash, &vlan->tnode,
84 br_vlan_tunnel_rht_params);
85 if (err)
86 goto out;
87
88 return 0;
89out:
90 vlan_tunnel_info_release(vlan);
91
92 return err;
93}
94
95/* Must be protected by RTNL.
96 * Must be called with vid in range from 1 to 4094 inclusive.
97 */
98int nbp_vlan_tunnel_info_add(const struct net_bridge_port *port, u16 vid,
99 u32 tun_id)
100{
101 struct net_bridge_vlan_group *vg;
102 struct net_bridge_vlan *vlan;
103
104 ASSERT_RTNL();
105
106 vg = nbp_vlan_group(port);
107 vlan = br_vlan_find(vg, vid);
108 if (!vlan)
109 return -EINVAL;
110
111 return __vlan_tunnel_info_add(vg, vlan, tun_id);
112}
113
114/* Must be protected by RTNL.
115 * Must be called with vid in range from 1 to 4094 inclusive.
116 */
117int nbp_vlan_tunnel_info_delete(const struct net_bridge_port *port, u16 vid)
118{
119 struct net_bridge_vlan_group *vg;
120 struct net_bridge_vlan *v;
121
122 ASSERT_RTNL();
123
124 vg = nbp_vlan_group(port);
125 v = br_vlan_find(vg, vid);
126 if (!v)
127 return -ENOENT;
128
129 vlan_tunnel_info_del(vg, v);
130
131 return 0;
132}
133
134static void __vlan_tunnel_info_flush(struct net_bridge_vlan_group *vg)
135{
136 struct net_bridge_vlan *vlan, *tmp;
137
138 list_for_each_entry_safe(vlan, tmp, &vg->vlan_list, vlist)
139 vlan_tunnel_info_del(vg, vlan);
140}
141
142void nbp_vlan_tunnel_info_flush(struct net_bridge_port *port)
143{
144 struct net_bridge_vlan_group *vg;
145
146 ASSERT_RTNL();
147
148 vg = nbp_vlan_group(port);
149 __vlan_tunnel_info_flush(vg);
150}
151
152int vlan_tunnel_init(struct net_bridge_vlan_group *vg)
153{
154 return rhashtable_init(&vg->tunnel_hash, &br_vlan_tunnel_rht_params);
155}
156
157void vlan_tunnel_deinit(struct net_bridge_vlan_group *vg)
158{
159 rhashtable_destroy(&vg->tunnel_hash);
160}
161
162void br_handle_ingress_vlan_tunnel(struct sk_buff *skb,
163 struct net_bridge_port *p,
164 struct net_bridge_vlan_group *vg)
165{
166 struct ip_tunnel_info *tinfo = skb_tunnel_info(skb);
167 struct net_bridge_vlan *vlan;
168
169 if (!vg || !tinfo)
170 return;
171
172 /* if already tagged, ignore */
173 if (skb_vlan_tagged(skb))
174 return;
175
176 /* lookup vid, given tunnel id */
177 vlan = br_vlan_tunnel_lookup(&vg->tunnel_hash, tinfo->key.tun_id);
178 if (!vlan)
179 return;
180
181 skb_dst_drop(skb);
182
183 __vlan_hwaccel_put_tag(skb, p->br->vlan_proto, vlan->vid);
184}
185
186int br_handle_egress_vlan_tunnel(struct sk_buff *skb,
187 struct net_bridge_vlan *vlan)
188{
189 IP_TUNNEL_DECLARE_FLAGS(flags) = { };
190 struct metadata_dst *tunnel_dst;
191 __be64 tunnel_id;
192
193 if (!vlan)
194 return 0;
195
196 tunnel_id = READ_ONCE(vlan->tinfo.tunnel_id);
197 if (!tunnel_id || unlikely(!skb_vlan_tag_present(skb)))
198 return 0;
199
200 skb_dst_drop(skb);
201 /* For 802.1ad (QinQ), skb_vlan_pop() incorrectly moves the C-VLAN
202 * from payload to hwaccel after clearing S-VLAN. We only need to
203 * clear the hwaccel S-VLAN; the C-VLAN must stay in payload for
204 * correct VXLAN encapsulation. This is also correct for 802.1Q
205 * where no C-VLAN exists in payload.
206 */
207 __vlan_hwaccel_clear_tag(skb);
208
209 if (BR_INPUT_SKB_CB(skb)->backup_nhid) {
210 __set_bit(IP_TUNNEL_KEY_BIT, flags);
211 tunnel_dst = __ip_tun_set_dst(0, 0, 0, 0, 0, flags,
212 tunnel_id, 0);
213 if (!tunnel_dst)
214 return -ENOMEM;
215
216 tunnel_dst->u.tun_info.mode |= IP_TUNNEL_INFO_TX |
217 IP_TUNNEL_INFO_BRIDGE;
218 tunnel_dst->u.tun_info.key.nhid =
219 BR_INPUT_SKB_CB(skb)->backup_nhid;
220 skb_dst_set(skb, &tunnel_dst->dst);
221
222 return 0;
223 }
224
225 tunnel_dst = rcu_dereference(vlan->tinfo.tunnel_dst);
226 if (tunnel_dst && dst_hold_safe(&tunnel_dst->dst))
227 skb_dst_set(skb, &tunnel_dst->dst);
228
229 return 0;
230}