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
 29struct 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
 44int l3mdev_fib_rule_match(struct net *net, struct flowi *fl,
 45			  struct fib_lookup_arg *arg);
 46
 47void l3mdev_update_flow(struct net *net, struct flowi *fl);
 48
 49int l3mdev_master_ifindex_rcu(const struct net_device *dev);
 50static 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
 61static 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
 79static inline
 80struct 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
104u32 l3mdev_fib_table_rcu(const struct net_device *dev);
105u32 l3mdev_fib_table_by_index(struct net *net, int ifindex);
106static 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
117static 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
136struct dst_entry *l3mdev_link_scope_lookup(struct net *net, struct flowi6 *fl6);
137
138static inline
139struct 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		master = skb->dev;
147
148	if (master && master->l3mdev_ops->l3mdev_l3_rcv)
149		skb = master->l3mdev_ops->l3mdev_l3_rcv(master, skb, proto);
150
151	return skb;
152}
153
154static inline
155struct sk_buff *l3mdev_ip_rcv(struct sk_buff *skb)
156{
157	return l3mdev_l3_rcv(skb, AF_INET);
158}
159
160static inline
161struct sk_buff *l3mdev_ip6_rcv(struct sk_buff *skb)
162{
163	return l3mdev_l3_rcv(skb, AF_INET6);
164}
165
166static inline
167struct sk_buff *l3mdev_l3_out(struct sock *sk, struct sk_buff *skb, u16 proto)
168{
169	struct net_device *dev = skb_dst(skb)->dev;
170
171	if (netif_is_l3_slave(dev)) {
172		struct net_device *master;
173
174		master = netdev_master_upper_dev_get_rcu(dev);
175		if (master && master->l3mdev_ops->l3mdev_l3_out)
176			skb = master->l3mdev_ops->l3mdev_l3_out(master, sk,
177								skb, proto);
178	}
179
180	return skb;
181}
182
183static inline
184struct sk_buff *l3mdev_ip_out(struct sock *sk, struct sk_buff *skb)
185{
186	return l3mdev_l3_out(sk, skb, AF_INET);
187}
188
189static inline
190struct sk_buff *l3mdev_ip6_out(struct sock *sk, struct sk_buff *skb)
191{
192	return l3mdev_l3_out(sk, skb, AF_INET6);
193}
194#else
195
196static inline int l3mdev_master_ifindex_rcu(const struct net_device *dev)
197{
198	return 0;
199}
200static inline int l3mdev_master_ifindex(struct net_device *dev)
201{
202	return 0;
203}
204
205static inline int l3mdev_master_ifindex_by_index(struct net *net, int ifindex)
206{
207	return 0;
208}
209
210static inline
211struct net_device *l3mdev_master_dev_rcu(const struct net_device *dev)
212{
213	return NULL;
214}
215
216static inline u32 l3mdev_fib_table_rcu(const struct net_device *dev)
217{
218	return 0;
219}
220static inline u32 l3mdev_fib_table(const struct net_device *dev)
221{
222	return 0;
223}
224static inline u32 l3mdev_fib_table_by_index(struct net *net, int ifindex)
225{
226	return 0;
227}
228
229static inline bool netif_index_is_l3_master(struct net *net, int ifindex)
230{
231	return false;
232}
233
234static inline
235struct dst_entry *l3mdev_link_scope_lookup(struct net *net, struct flowi6 *fl6)
236{
237	return NULL;
238}
239
240static inline
241struct sk_buff *l3mdev_ip_rcv(struct sk_buff *skb)
242{
243	return skb;
244}
245
246static inline
247struct sk_buff *l3mdev_ip6_rcv(struct sk_buff *skb)
248{
249	return skb;
250}
251
252static inline
253struct sk_buff *l3mdev_ip_out(struct sock *sk, struct sk_buff *skb)
254{
255	return skb;
256}
257
258static inline
259struct sk_buff *l3mdev_ip6_out(struct sock *sk, struct sk_buff *skb)
260{
261	return skb;
262}
263
264static inline
265int l3mdev_fib_rule_match(struct net *net, struct flowi *fl,
266			  struct fib_lookup_arg *arg)
267{
268	return 1;
269}
270static inline
271void l3mdev_update_flow(struct net *net, struct flowi *fl)
272{
273}
274#endif
275
276#endif /* _NET_L3MDEV_H_ */