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         .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 }