include/net/l3mdev.h

   1 /*
   2  * include/net/l3mdev.h - L3 master device API
   3  * Copyright (c) 2015 Cumulus Networks
   4  * Copyright (c) 2015 David Ahern <dsa@cumulusnetworks.com>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  */
  11 #ifndef _NET_L3MDEV_H_
  12 #define _NET_L3MDEV_H_
  13
  14 #include <net/dst.h>
  15 #include <net/fib_rules.h>
  16
  17 /**
  18  * struct l3mdev_ops - l3mdev operations
  19  *
  20  * @l3mdev_fib_table: Get FIB table id to use for lookups
  21  *
  22  * @l3mdev_l3_rcv:    Hook in L3 receive path
  23  *
  24  * @l3mdev_l3_out:    Hook in L3 output path
  25  *
  26  * @l3mdev_link_scope_lookup: IPv6 lookup for linklocal and mcast destinations
  27  */
  28
  29 struct l3mdev_ops {
  30         u32             (*l3mdev_fib_table)(const struct net_device *dev);
  31         struct sk_buff * (*l3mdev_l3_rcv)(struct net_device *dev,
  32                                           struct sk_buff *skb, u16 proto);
  33         struct sk_buff * (*l3mdev_l3_out)(struct net_device *dev,
  34                                           struct sock *sk, struct sk_buff *skb,
  35                                           u16 proto);
  36
  37         /* IPv6 ops */
  38         struct dst_entry * (*l3mdev_link_scope_lookup)(const struct net_device *dev,
  39                                                  struct flowi6 *fl6);
  40 };
  41
  42 #ifdef CONFIG_NET_L3_MASTER_DEV
  43
  44 int l3mdev_fib_rule_match(struct net *net, struct flowi *fl,
  45                           struct fib_lookup_arg *arg);
  46
  47 void l3mdev_update_flow(struct net *net, struct flowi *fl);
  48
  49 int l3mdev_master_ifindex_rcu(const struct net_device *dev);
  50 static inline int l3mdev_master_ifindex(struct net_device *dev)
  51 {
  52         int ifindex;
  53
  54         rcu_read_lock();
  55         ifindex = l3mdev_master_ifindex_rcu(dev);
  56         rcu_read_unlock();
  57
  58         return ifindex;
  59 }
  60
  61 static inline int l3mdev_master_ifindex_by_index(struct net *net, int ifindex)
  62 {
  63         struct net_device *dev;
  64         int rc = 0;
  65
  66         if (likely(ifindex)) {
  67                 rcu_read_lock();
  68
  69                 dev = dev_get_by_index_rcu(net, ifindex);
  70                 if (dev)
  71                         rc = l3mdev_master_ifindex_rcu(dev);
  72
  73                 rcu_read_unlock();
  74         }
  75
  76         return rc;
  77 }
  78
  79 static inline
  80 struct net_device *l3mdev_master_dev_rcu(const struct net_device *_dev)
  81 {
  82         /* netdev_master_upper_dev_get_rcu calls
  83          * list_first_or_null_rcu to walk the upper dev list.
  84          * list_first_or_null_rcu does not handle a const arg. We aren't
  85          * making changes, just want the master device from that list so
  86          * typecast to remove the const
  87          */
  88         struct net_device *dev = (struct net_device *)_dev;
  89         struct net_device *master;
  90
  91         if (!dev)
  92                 return NULL;
  93
  94         if (netif_is_l3_master(dev))
  95                 master = dev;
  96         else if (netif_is_l3_slave(dev))
  97                 master = netdev_master_upper_dev_get_rcu(dev);
  98         else
  99                 master = NULL;
 100
 101         return master;
 102 }
 103
 104 u32 l3mdev_fib_table_rcu(const struct net_device *dev);
 105 u32 l3mdev_fib_table_by_index(struct net *net, int ifindex);
 106 static inline u32 l3mdev_fib_table(const struct net_device *dev)
 107 {
 108         u32 tb_id;
 109
 110         rcu_read_lock();
 111         tb_id = l3mdev_fib_table_rcu(dev);
 112         rcu_read_unlock();
 113
 114         return tb_id;
 115 }
 116
 117 static inline bool netif_index_is_l3_master(struct net *net, int ifindex)
 118 {
 119         struct net_device *dev;
 120         bool rc = false;
 121
 122         if (ifindex == 0)
 123                 return false;
 124
 125         rcu_read_lock();
 126
 127         dev = dev_get_by_index_rcu(net, ifindex);
 128         if (dev)
 129                 rc = netif_is_l3_master(dev);
 130
 131         rcu_read_unlock();
 132
 133         return rc;
 134 }
 135
 136 struct dst_entry *l3mdev_link_scope_lookup(struct net *net, struct flowi6 *fl6);
 137
 138 static inline
 139 struct sk_buff *l3mdev_l3_rcv(struct sk_buff *skb, u16 proto)
 140 {
 141         struct net_device *master = NULL;
 142
 143         if (netif_is_l3_slave(skb->dev))
 144                 master = netdev_master_upper_dev_get_rcu(skb->dev);
 145         else if (netif_is_l3_master(skb->dev) ||
 146                  netif_has_l3_rx_handler(skb->dev))
 147                 master = skb->dev;
 148
 149         if (master && master->l3mdev_ops->l3mdev_l3_rcv)
 150                 skb = master->l3mdev_ops->l3mdev_l3_rcv(master, skb, proto);
 151
 152         return skb;
 153 }
 154
 155 static inline
 156 struct sk_buff *l3mdev_ip_rcv(struct sk_buff *skb)
 157 {
 158         return l3mdev_l3_rcv(skb, AF_INET);
 159 }
 160
 161 static inline
 162 struct sk_buff *l3mdev_ip6_rcv(struct sk_buff *skb)
 163 {
 164         return l3mdev_l3_rcv(skb, AF_INET6);
 165 }
 166
 167 static inline
 168 struct sk_buff *l3mdev_l3_out(struct sock *sk, struct sk_buff *skb, u16 proto)
 169 {
 170         struct net_device *dev = skb_dst(skb)->dev;
 171
 172         if (netif_is_l3_slave(dev)) {
 173                 struct net_device *master;
 174
 175                 master = netdev_master_upper_dev_get_rcu(dev);
 176                 if (master && master->l3mdev_ops->l3mdev_l3_out)
 177                         skb = master->l3mdev_ops->l3mdev_l3_out(master, sk,
 178                                                                 skb, proto);
 179         }
 180
 181         return skb;
 182 }
 183
 184 static inline
 185 struct sk_buff *l3mdev_ip_out(struct sock *sk, struct sk_buff *skb)
 186 {
 187         return l3mdev_l3_out(sk, skb, AF_INET);
 188 }
 189
 190 static inline
 191 struct sk_buff *l3mdev_ip6_out(struct sock *sk, struct sk_buff *skb)
 192 {
 193         return l3mdev_l3_out(sk, skb, AF_INET6);
 194 }
 195 #else
 196
 197 static inline int l3mdev_master_ifindex_rcu(const struct net_device *dev)
 198 {
 199         return 0;
 200 }
 201 static inline int l3mdev_master_ifindex(struct net_device *dev)
 202 {
 203         return 0;
 204 }
 205
 206 static inline int l3mdev_master_ifindex_by_index(struct net *net, int ifindex)
 207 {
 208         return 0;
 209 }
 210
 211 static inline
 212 struct net_device *l3mdev_master_dev_rcu(const struct net_device *dev)
 213 {
 214         return NULL;
 215 }
 216
 217 static inline u32 l3mdev_fib_table_rcu(const struct net_device *dev)
 218 {
 219         return 0;
 220 }
 221 static inline u32 l3mdev_fib_table(const struct net_device *dev)
 222 {
 223         return 0;
 224 }
 225 static inline u32 l3mdev_fib_table_by_index(struct net *net, int ifindex)
 226 {
 227         return 0;
 228 }
 229
 230 static inline bool netif_index_is_l3_master(struct net *net, int ifindex)
 231 {
 232         return false;
 233 }
 234
 235 static inline
 236 struct dst_entry *l3mdev_link_scope_lookup(struct net *net, struct flowi6 *fl6)
 237 {
 238         return NULL;
 239 }
 240
 241 static inline
 242 struct sk_buff *l3mdev_ip_rcv(struct sk_buff *skb)
 243 {
 244         return skb;
 245 }
 246
 247 static inline
 248 struct sk_buff *l3mdev_ip6_rcv(struct sk_buff *skb)
 249 {
 250         return skb;
 251 }
 252
 253 static inline
 254 struct sk_buff *l3mdev_ip_out(struct sock *sk, struct sk_buff *skb)
 255 {
 256         return skb;
 257 }
 258
 259 static inline
 260 struct sk_buff *l3mdev_ip6_out(struct sock *sk, struct sk_buff *skb)
 261 {
 262         return skb;
 263 }
 264
 265 static inline
 266 int l3mdev_fib_rule_match(struct net *net, struct flowi *fl,
 267                           struct fib_lookup_arg *arg)
 268 {
 269         return 1;
 270 }
 271 static inline
 272 void l3mdev_update_flow(struct net *net, struct flowi *fl)
 273 {
 274 }
 275 #endif
 276
 277 #endif /* _NET_L3MDEV_H_ */