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 int l3mdev_master_upper_ifindex_by_index_rcu(struct net *net, int ifindex);
 105 static inline
 106 int l3mdev_master_upper_ifindex_by_index(struct net *net, int ifindex)
 107 {
 108         rcu_read_lock();
 109         ifindex = l3mdev_master_upper_ifindex_by_index_rcu(net, ifindex);
 110         rcu_read_unlock();
 111
 112         return ifindex;
 113 }
 114
 115 u32 l3mdev_fib_table_rcu(const struct net_device *dev);
 116 u32 l3mdev_fib_table_by_index(struct net *net, int ifindex);
 117 static inline u32 l3mdev_fib_table(const struct net_device *dev)
 118 {
 119         u32 tb_id;
 120
 121         rcu_read_lock();
 122         tb_id = l3mdev_fib_table_rcu(dev);
 123         rcu_read_unlock();
 124
 125         return tb_id;
 126 }
 127
 128 static inline bool netif_index_is_l3_master(struct net *net, int ifindex)
 129 {
 130         struct net_device *dev;
 131         bool rc = false;
 132
 133         if (ifindex == 0)
 134                 return false;
 135
 136         rcu_read_lock();
 137
 138         dev = dev_get_by_index_rcu(net, ifindex);
 139         if (dev)
 140                 rc = netif_is_l3_master(dev);
 141
 142         rcu_read_unlock();
 143
 144         return rc;
 145 }
 146
 147 struct dst_entry *l3mdev_link_scope_lookup(struct net *net, struct flowi6 *fl6);
 148
 149 static inline
 150 struct sk_buff *l3mdev_l3_rcv(struct sk_buff *skb, u16 proto)
 151 {
 152         struct net_device *master = NULL;
 153
 154         if (netif_is_l3_slave(skb->dev))
 155                 master = netdev_master_upper_dev_get_rcu(skb->dev);
 156         else if (netif_is_l3_master(skb->dev) ||
 157                  netif_has_l3_rx_handler(skb->dev))
 158                 master = skb->dev;
 159
 160         if (master && master->l3mdev_ops->l3mdev_l3_rcv)
 161                 skb = master->l3mdev_ops->l3mdev_l3_rcv(master, skb, proto);
 162
 163         return skb;
 164 }
 165
 166 static inline
 167 struct sk_buff *l3mdev_ip_rcv(struct sk_buff *skb)
 168 {
 169         return l3mdev_l3_rcv(skb, AF_INET);
 170 }
 171
 172 static inline
 173 struct sk_buff *l3mdev_ip6_rcv(struct sk_buff *skb)
 174 {
 175         return l3mdev_l3_rcv(skb, AF_INET6);
 176 }
 177
 178 static inline
 179 struct sk_buff *l3mdev_l3_out(struct sock *sk, struct sk_buff *skb, u16 proto)
 180 {
 181         struct net_device *dev = skb_dst(skb)->dev;
 182
 183         if (netif_is_l3_slave(dev)) {
 184                 struct net_device *master;
 185
 186                 master = netdev_master_upper_dev_get_rcu(dev);
 187                 if (master && master->l3mdev_ops->l3mdev_l3_out)
 188                         skb = master->l3mdev_ops->l3mdev_l3_out(master, sk,
 189                                                                 skb, proto);
 190         }
 191
 192         return skb;
 193 }
 194
 195 static inline
 196 struct sk_buff *l3mdev_ip_out(struct sock *sk, struct sk_buff *skb)
 197 {
 198         return l3mdev_l3_out(sk, skb, AF_INET);
 199 }
 200
 201 static inline
 202 struct sk_buff *l3mdev_ip6_out(struct sock *sk, struct sk_buff *skb)
 203 {
 204         return l3mdev_l3_out(sk, skb, AF_INET6);
 205 }
 206 #else
 207
 208 static inline int l3mdev_master_ifindex_rcu(const struct net_device *dev)
 209 {
 210         return 0;
 211 }
 212 static inline int l3mdev_master_ifindex(struct net_device *dev)
 213 {
 214         return 0;
 215 }
 216
 217 static inline int l3mdev_master_ifindex_by_index(struct net *net, int ifindex)
 218 {
 219         return 0;
 220 }
 221
 222 static inline
 223 int l3mdev_master_upper_ifindex_by_index_rcu(struct net *net, int ifindex)
 224 {
 225         return 0;
 226 }
 227 static inline
 228 int l3mdev_master_upper_ifindex_by_index(struct net *net, int ifindex)
 229 {
 230         return 0;
 231 }
 232
 233 static inline
 234 struct net_device *l3mdev_master_dev_rcu(const struct net_device *dev)
 235 {
 236         return NULL;
 237 }
 238
 239 static inline u32 l3mdev_fib_table_rcu(const struct net_device *dev)
 240 {
 241         return 0;
 242 }
 243 static inline u32 l3mdev_fib_table(const struct net_device *dev)
 244 {
 245         return 0;
 246 }
 247 static inline u32 l3mdev_fib_table_by_index(struct net *net, int ifindex)
 248 {
 249         return 0;
 250 }
 251
 252 static inline bool netif_index_is_l3_master(struct net *net, int ifindex)
 253 {
 254         return false;
 255 }
 256
 257 static inline
 258 struct dst_entry *l3mdev_link_scope_lookup(struct net *net, struct flowi6 *fl6)
 259 {
 260         return NULL;
 261 }
 262
 263 static inline
 264 struct sk_buff *l3mdev_ip_rcv(struct sk_buff *skb)
 265 {
 266         return skb;
 267 }
 268
 269 static inline
 270 struct sk_buff *l3mdev_ip6_rcv(struct sk_buff *skb)
 271 {
 272         return skb;
 273 }
 274
 275 static inline
 276 struct sk_buff *l3mdev_ip_out(struct sock *sk, struct sk_buff *skb)
 277 {
 278         return skb;
 279 }
 280
 281 static inline
 282 struct sk_buff *l3mdev_ip6_out(struct sock *sk, struct sk_buff *skb)
 283 {
 284         return skb;
 285 }
 286
 287 static inline
 288 int l3mdev_fib_rule_match(struct net *net, struct flowi *fl,
 289                           struct fib_lookup_arg *arg)
 290 {
 291         return 1;
 292 }
 293 static inline
 294 void l3mdev_update_flow(struct net *net, struct flowi *fl)
 295 {
 296 }
 297 #endif
 298
 299 #endif /* _NET_L3MDEV_H_ */