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