net/bridge/br_vlan_tunnel.c

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