net/bridge/br_vlan_tunnel.c

   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 }