xref: /openbmc/linux/include/net/l3mdev.h (revision b737eecd)
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 enum 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 
21 typedef 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 
35 struct 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 
50 int l3mdev_table_lookup_register(enum l3mdev_type l3type,
51 				 lookup_by_table_id_t fn);
52 
53 void l3mdev_table_lookup_unregister(enum l3mdev_type l3type,
54 				    lookup_by_table_id_t fn);
55 
56 int l3mdev_ifindex_lookup_by_table_id(enum l3mdev_type l3type, struct net *net,
57 				      u32 table_id);
58 
59 int l3mdev_fib_rule_match(struct net *net, struct flowi *fl,
60 			  struct fib_lookup_arg *arg);
61 
62 void l3mdev_update_flow(struct net *net, struct flowi *fl);
63 
64 int l3mdev_master_ifindex_rcu(const struct net_device *dev);
65 static 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 
76 static 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 
94 static inline
95 struct 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 
119 int l3mdev_master_upper_ifindex_by_index_rcu(struct net *net, int ifindex);
120 static inline
121 int 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 
130 u32 l3mdev_fib_table_rcu(const struct net_device *dev);
131 u32 l3mdev_fib_table_by_index(struct net *net, int ifindex);
132 static 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 
143 static 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 
162 struct dst_entry *l3mdev_link_scope_lookup(struct net *net, struct flowi6 *fl6);
163 
164 static inline
165 struct 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 
181 static inline
182 struct sk_buff *l3mdev_ip_rcv(struct sk_buff *skb)
183 {
184 	return l3mdev_l3_rcv(skb, AF_INET);
185 }
186 
187 static inline
188 struct sk_buff *l3mdev_ip6_rcv(struct sk_buff *skb)
189 {
190 	return l3mdev_l3_rcv(skb, AF_INET6);
191 }
192 
193 static inline
194 struct 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 
210 static inline
211 struct sk_buff *l3mdev_ip_out(struct sock *sk, struct sk_buff *skb)
212 {
213 	return l3mdev_l3_out(sk, skb, AF_INET);
214 }
215 
216 static inline
217 struct 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 
223 static inline int l3mdev_master_ifindex_rcu(const struct net_device *dev)
224 {
225 	return 0;
226 }
227 static inline int l3mdev_master_ifindex(struct net_device *dev)
228 {
229 	return 0;
230 }
231 
232 static inline int l3mdev_master_ifindex_by_index(struct net *net, int ifindex)
233 {
234 	return 0;
235 }
236 
237 static inline
238 int l3mdev_master_upper_ifindex_by_index_rcu(struct net *net, int ifindex)
239 {
240 	return 0;
241 }
242 static inline
243 int l3mdev_master_upper_ifindex_by_index(struct net *net, int ifindex)
244 {
245 	return 0;
246 }
247 
248 static inline
249 struct net_device *l3mdev_master_dev_rcu(const struct net_device *dev)
250 {
251 	return NULL;
252 }
253 
254 static inline u32 l3mdev_fib_table_rcu(const struct net_device *dev)
255 {
256 	return 0;
257 }
258 static inline u32 l3mdev_fib_table(const struct net_device *dev)
259 {
260 	return 0;
261 }
262 static inline u32 l3mdev_fib_table_by_index(struct net *net, int ifindex)
263 {
264 	return 0;
265 }
266 
267 static inline bool netif_index_is_l3_master(struct net *net, int ifindex)
268 {
269 	return false;
270 }
271 
272 static inline
273 struct dst_entry *l3mdev_link_scope_lookup(struct net *net, struct flowi6 *fl6)
274 {
275 	return NULL;
276 }
277 
278 static inline
279 struct sk_buff *l3mdev_ip_rcv(struct sk_buff *skb)
280 {
281 	return skb;
282 }
283 
284 static inline
285 struct sk_buff *l3mdev_ip6_rcv(struct sk_buff *skb)
286 {
287 	return skb;
288 }
289 
290 static inline
291 struct sk_buff *l3mdev_ip_out(struct sock *sk, struct sk_buff *skb)
292 {
293 	return skb;
294 }
295 
296 static inline
297 struct sk_buff *l3mdev_ip6_out(struct sock *sk, struct sk_buff *skb)
298 {
299 	return skb;
300 }
301 
302 static inline
303 int l3mdev_table_lookup_register(enum l3mdev_type l3type,
304 				 lookup_by_table_id_t fn)
305 {
306 	return -EOPNOTSUPP;
307 }
308 
309 static inline
310 void l3mdev_table_lookup_unregister(enum l3mdev_type l3type,
311 				    lookup_by_table_id_t fn)
312 {
313 }
314 
315 static inline
316 int l3mdev_ifindex_lookup_by_table_id(enum l3mdev_type l3type, struct net *net,
317 				      u32 table_id)
318 {
319 	return -ENODEV;
320 }
321 
322 static inline
323 int l3mdev_fib_rule_match(struct net *net, struct flowi *fl,
324 			  struct fib_lookup_arg *arg)
325 {
326 	return 1;
327 }
328 static inline
329 void l3mdev_update_flow(struct net *net, struct flowi *fl)
330 {
331 }
332 #endif
333 
334 #endif /* _NET_L3MDEV_H_ */
335