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                 master = skb->dev;
 158
 159         if (master && master->l3mdev_ops->l3mdev_l3_rcv)
 160                 skb = master->l3mdev_ops->l3mdev_l3_rcv(master, skb, proto);
 161
 162         return skb;
 163 }
 164
 165 static inline
 166 struct sk_buff *l3mdev_ip_rcv(struct sk_buff *skb)
 167 {
 168         return l3mdev_l3_rcv(skb, AF_INET);
 169 }
 170
 171 static inline
 172 struct sk_buff *l3mdev_ip6_rcv(struct sk_buff *skb)
 173 {
 174         return l3mdev_l3_rcv(skb, AF_INET6);
 175 }
 176
 177 static inline
 178 struct sk_buff *l3mdev_l3_out(struct sock *sk, struct sk_buff *skb, u16 proto)
 179 {
 180         struct net_device *dev = skb_dst(skb)->dev;
 181
 182         if (netif_is_l3_slave(dev)) {
 183                 struct net_device *master;
 184
 185                 master = netdev_master_upper_dev_get_rcu(dev);
 186                 if (master && master->l3mdev_ops->l3mdev_l3_out)
 187                         skb = master->l3mdev_ops->l3mdev_l3_out(master, sk,
 188                                                                 skb, proto);
 189         }
 190
 191         return skb;
 192 }
 193
 194 static inline
 195 struct sk_buff *l3mdev_ip_out(struct sock *sk, struct sk_buff *skb)
 196 {
 197         return l3mdev_l3_out(sk, skb, AF_INET);
 198 }
 199
 200 static inline
 201 struct sk_buff *l3mdev_ip6_out(struct sock *sk, struct sk_buff *skb)
 202 {
 203         return l3mdev_l3_out(sk, skb, AF_INET6);
 204 }
 205 #else
 206
 207 static inline int l3mdev_master_ifindex_rcu(const struct net_device *dev)
 208 {
 209         return 0;
 210 }
 211 static inline int l3mdev_master_ifindex(struct net_device *dev)
 212 {
 213         return 0;
 214 }
 215
 216 static inline int l3mdev_master_ifindex_by_index(struct net *net, int ifindex)
 217 {
 218         return 0;
 219 }
 220
 221 static inline
 222 int l3mdev_master_upper_ifindex_by_index_rcu(struct net *net, int ifindex)
 223 {
 224         return 0;
 225 }
 226 static inline
 227 int l3mdev_master_upper_ifindex_by_index(struct net *net, int ifindex)
 228 {
 229         return 0;
 230 }
 231
 232 static inline
 233 struct net_device *l3mdev_master_dev_rcu(const struct net_device *dev)
 234 {
 235         return NULL;
 236 }
 237
 238 static inline u32 l3mdev_fib_table_rcu(const struct net_device *dev)
 239 {
 240         return 0;
 241 }
 242 static inline u32 l3mdev_fib_table(const struct net_device *dev)
 243 {
 244         return 0;
 245 }
 246 static inline u32 l3mdev_fib_table_by_index(struct net *net, int ifindex)
 247 {
 248         return 0;
 249 }
 250
 251 static inline bool netif_index_is_l3_master(struct net *net, int ifindex)
 252 {
 253         return false;
 254 }
 255
 256 static inline
 257 struct dst_entry *l3mdev_link_scope_lookup(struct net *net, struct flowi6 *fl6)
 258 {
 259         return NULL;
 260 }
 261
 262 static inline
 263 struct sk_buff *l3mdev_ip_rcv(struct sk_buff *skb)
 264 {
 265         return skb;
 266 }
 267
 268 static inline
 269 struct sk_buff *l3mdev_ip6_rcv(struct sk_buff *skb)
 270 {
 271         return skb;
 272 }
 273
 274 static inline
 275 struct sk_buff *l3mdev_ip_out(struct sock *sk, struct sk_buff *skb)
 276 {
 277         return skb;
 278 }
 279
 280 static inline
 281 struct sk_buff *l3mdev_ip6_out(struct sock *sk, struct sk_buff *skb)
 282 {
 283         return skb;
 284 }
 285
 286 static inline
 287 int l3mdev_fib_rule_match(struct net *net, struct flowi *fl,
 288                           struct fib_lookup_arg *arg)
 289 {
 290         return 1;
 291 }
 292 static inline
 293 void l3mdev_update_flow(struct net *net, struct flowi *fl)
 294 {
 295 }
 296 #endif
 297
 298 #endif /* _NET_L3MDEV_H_ */