1/* SPDX-License-Identifier: GPL-2.0-or-later */
  2/*
  3 * include/net/l3mdev.h - L3 master device API
  4 * Copyright (c) 2015 Cumulus Networks
  5 * Copyright (c) 2015 David Ahern <dsa@cumulusnetworks.com>
  6 */
  7#ifndef _NET_L3MDEV_H_
  8#define _NET_L3MDEV_H_
  9
 10#include <net/dst.h>
 11#include <net/fib_rules.h>
 12
 13enum l3mdev_type {
 14	L3MDEV_TYPE_UNSPEC,
 15	L3MDEV_TYPE_VRF,
 16	__L3MDEV_TYPE_MAX
 17};
 18
 19#define L3MDEV_TYPE_MAX (__L3MDEV_TYPE_MAX - 1)
 20
 21typedef int (*lookup_by_table_id_t)(struct net *net, u32 table_d);
 22
 23/**
 24 * struct l3mdev_ops - l3mdev operations
 25 *
 26 * @l3mdev_fib_table: Get FIB table id to use for lookups
 27 *
 28 * @l3mdev_l3_rcv:    Hook in L3 receive path
 29 *
 30 * @l3mdev_l3_out:    Hook in L3 output path
 31 *
 32 * @l3mdev_link_scope_lookup: IPv6 lookup for linklocal and mcast destinations
 33 */
 34
 35struct l3mdev_ops {
 36	u32		(*l3mdev_fib_table)(const struct net_device *dev);
 37	struct sk_buff * (*l3mdev_l3_rcv)(struct net_device *dev,
 38					  struct sk_buff *skb, u16 proto);
 39	struct sk_buff * (*l3mdev_l3_out)(struct net_device *dev,
 40					  struct sock *sk, struct sk_buff *skb,
 41					  u16 proto);
 42
 43	/* IPv6 ops */
 44	struct dst_entry * (*l3mdev_link_scope_lookup)(const struct net_device *dev,
 45						 struct flowi6 *fl6);
 46};
 47
 48#ifdef CONFIG_NET_L3_MASTER_DEV
 49
 50int l3mdev_table_lookup_register(enum l3mdev_type l3type,
 51				 lookup_by_table_id_t fn);
 52
 53void l3mdev_table_lookup_unregister(enum l3mdev_type l3type,
 54				    lookup_by_table_id_t fn);
 55
 56int l3mdev_ifindex_lookup_by_table_id(enum l3mdev_type l3type, struct net *net,
 57				      u32 table_id);
 58
 59int l3mdev_fib_rule_match(struct net *net, struct flowi *fl,
 60			  struct fib_lookup_arg *arg);
 61
 62void l3mdev_update_flow(struct net *net, struct flowi *fl);
 63
 64int l3mdev_master_ifindex_rcu(const struct net_device *dev);
 65static inline int l3mdev_master_ifindex(struct net_device *dev)
 66{
 67	int ifindex;
 68
 69	rcu_read_lock();
 70	ifindex = l3mdev_master_ifindex_rcu(dev);
 71	rcu_read_unlock();
 72
 73	return ifindex;
 74}
 75
 76static inline int l3mdev_master_ifindex_by_index(struct net *net, int ifindex)
 77{
 78	struct net_device *dev;
 79	int rc = 0;
 80
 81	if (likely(ifindex)) {
 82		rcu_read_lock();
 83
 84		dev = dev_get_by_index_rcu(net, ifindex);
 85		if (dev)
 86			rc = l3mdev_master_ifindex_rcu(dev);
 87
 88		rcu_read_unlock();
 89	}
 90
 91	return rc;
 92}
 93
 94static inline
 95struct net_device *l3mdev_master_dev_rcu(const struct net_device *_dev)
 96{
 97	/* netdev_master_upper_dev_get_rcu calls
 98	 * list_first_or_null_rcu to walk the upper dev list.
 99	 * list_first_or_null_rcu does not handle a const arg. We aren't
100	 * making changes, just want the master device from that list so
101	 * typecast to remove the const
102	 */
103	struct net_device *dev = (struct net_device *)_dev;
104	struct net_device *master;
105
106	if (!dev)
107		return NULL;
108
109	if (netif_is_l3_master(dev))
110		master = dev;
111	else if (netif_is_l3_slave(dev))
112		master = netdev_master_upper_dev_get_rcu(dev);
113	else
114		master = NULL;
115
116	return master;
117}
118
119int l3mdev_master_upper_ifindex_by_index_rcu(struct net *net, int ifindex);
120static inline
121int l3mdev_master_upper_ifindex_by_index(struct net *net, int ifindex)
122{
123	rcu_read_lock();
124	ifindex = l3mdev_master_upper_ifindex_by_index_rcu(net, ifindex);
125	rcu_read_unlock();
126
127	return ifindex;
128}
129
130u32 l3mdev_fib_table_rcu(const struct net_device *dev);
131u32 l3mdev_fib_table_by_index(struct net *net, int ifindex);
132static inline u32 l3mdev_fib_table(const struct net_device *dev)
133{
134	u32 tb_id;
135
136	rcu_read_lock();
137	tb_id = l3mdev_fib_table_rcu(dev);
138	rcu_read_unlock();
139
140	return tb_id;
141}
142
143static inline bool netif_index_is_l3_master(struct net *net, int ifindex)
144{
145	struct net_device *dev;
146	bool rc = false;
147
148	if (ifindex == 0)
149		return false;
150
151	rcu_read_lock();
152
153	dev = dev_get_by_index_rcu(net, ifindex);
154	if (dev)
155		rc = netif_is_l3_master(dev);
156
157	rcu_read_unlock();
158
159	return rc;
160}
161
162struct dst_entry *l3mdev_link_scope_lookup(struct net *net, struct flowi6 *fl6);
163
164static inline
165struct sk_buff *l3mdev_l3_rcv(struct sk_buff *skb, u16 proto)
166{
167	struct net_device *master = NULL;
168
169	if (netif_is_l3_slave(skb->dev))
170		master = netdev_master_upper_dev_get_rcu(skb->dev);
171	else if (netif_is_l3_master(skb->dev) ||
172		 netif_has_l3_rx_handler(skb->dev))
173		master = skb->dev;
174
175	if (master && master->l3mdev_ops->l3mdev_l3_rcv)
176		skb = master->l3mdev_ops->l3mdev_l3_rcv(master, skb, proto);
177
178	return skb;
179}
180
181static inline
182struct sk_buff *l3mdev_ip_rcv(struct sk_buff *skb)
183{
184	return l3mdev_l3_rcv(skb, AF_INET);
185}
186
187static inline
188struct sk_buff *l3mdev_ip6_rcv(struct sk_buff *skb)
189{
190	return l3mdev_l3_rcv(skb, AF_INET6);
191}
192
193static inline
194struct sk_buff *l3mdev_l3_out(struct sock *sk, struct sk_buff *skb, u16 proto)
195{
196	struct net_device *dev = skb_dst(skb)->dev;
197
198	if (netif_is_l3_slave(dev)) {
199		struct net_device *master;
200
201		master = netdev_master_upper_dev_get_rcu(dev);
202		if (master && master->l3mdev_ops->l3mdev_l3_out)
203			skb = master->l3mdev_ops->l3mdev_l3_out(master, sk,
204								skb, proto);
205	}
206
207	return skb;
208}
209
210static inline
211struct sk_buff *l3mdev_ip_out(struct sock *sk, struct sk_buff *skb)
212{
213	return l3mdev_l3_out(sk, skb, AF_INET);
214}
215
216static inline
217struct sk_buff *l3mdev_ip6_out(struct sock *sk, struct sk_buff *skb)
218{
219	return l3mdev_l3_out(sk, skb, AF_INET6);
220}
221#else
222
223static inline int l3mdev_master_ifindex_rcu(const struct net_device *dev)
224{
225	return 0;
226}
227static inline int l3mdev_master_ifindex(struct net_device *dev)
228{
229	return 0;
230}
231
232static inline int l3mdev_master_ifindex_by_index(struct net *net, int ifindex)
233{
234	return 0;
235}
236
237static inline
238int l3mdev_master_upper_ifindex_by_index_rcu(struct net *net, int ifindex)
239{
240	return 0;
241}
242static inline
243int l3mdev_master_upper_ifindex_by_index(struct net *net, int ifindex)
244{
245	return 0;
246}
247
248static inline
249struct net_device *l3mdev_master_dev_rcu(const struct net_device *dev)
250{
251	return NULL;
252}
253
254static inline u32 l3mdev_fib_table_rcu(const struct net_device *dev)
255{
256	return 0;
257}
258static inline u32 l3mdev_fib_table(const struct net_device *dev)
259{
260	return 0;
261}
262static inline u32 l3mdev_fib_table_by_index(struct net *net, int ifindex)
263{
264	return 0;
265}
266
267static inline bool netif_index_is_l3_master(struct net *net, int ifindex)
268{
269	return false;
270}
271
272static inline
273struct dst_entry *l3mdev_link_scope_lookup(struct net *net, struct flowi6 *fl6)
274{
275	return NULL;
276}
277
278static inline
279struct sk_buff *l3mdev_ip_rcv(struct sk_buff *skb)
280{
281	return skb;
282}
283
284static inline
285struct sk_buff *l3mdev_ip6_rcv(struct sk_buff *skb)
286{
287	return skb;
288}
289
290static inline
291struct sk_buff *l3mdev_ip_out(struct sock *sk, struct sk_buff *skb)
292{
293	return skb;
294}
295
296static inline
297struct sk_buff *l3mdev_ip6_out(struct sock *sk, struct sk_buff *skb)
298{
299	return skb;
300}
301
302static inline
303int l3mdev_table_lookup_register(enum l3mdev_type l3type,
304				 lookup_by_table_id_t fn)
305{
306	return -EOPNOTSUPP;
307}
308
309static inline
310void l3mdev_table_lookup_unregister(enum l3mdev_type l3type,
311				    lookup_by_table_id_t fn)
312{
313}
314
315static inline
316int l3mdev_ifindex_lookup_by_table_id(enum l3mdev_type l3type, struct net *net,
317				      u32 table_id)
318{
319	return -ENODEV;
320}
321
322static inline
323int l3mdev_fib_rule_match(struct net *net, struct flowi *fl,
324			  struct fib_lookup_arg *arg)
325{
326	return 1;
327}
328static inline
329void l3mdev_update_flow(struct net *net, struct flowi *fl)
330{
331}
332#endif
333
334#endif /* _NET_L3MDEV_H_ */