xref: /linux/include/net/udp_tunnel.h (revision ab93e0dd72c37d378dd936f031ffb83ff2bd87ce)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __NET_UDP_TUNNEL_H
3 #define __NET_UDP_TUNNEL_H
4 
5 #include <net/ip_tunnels.h>
6 #include <net/udp.h>
7 
8 #if IS_ENABLED(CONFIG_IPV6)
9 #include <net/ipv6.h>
10 #include <net/ipv6_stubs.h>
11 #endif
12 
13 struct udp_port_cfg {
14 	u8			family;
15 
16 	/* Used only for kernel-created sockets */
17 	union {
18 		struct in_addr		local_ip;
19 #if IS_ENABLED(CONFIG_IPV6)
20 		struct in6_addr		local_ip6;
21 #endif
22 	};
23 
24 	union {
25 		struct in_addr		peer_ip;
26 #if IS_ENABLED(CONFIG_IPV6)
27 		struct in6_addr		peer_ip6;
28 #endif
29 	};
30 
31 	__be16			local_udp_port;
32 	__be16			peer_udp_port;
33 	int			bind_ifindex;
34 	unsigned int		use_udp_checksums:1,
35 				use_udp6_tx_checksums:1,
36 				use_udp6_rx_checksums:1,
37 				ipv6_v6only:1;
38 };
39 
40 int udp_sock_create4(struct net *net, struct udp_port_cfg *cfg,
41 		     struct socket **sockp);
42 
43 #if IS_ENABLED(CONFIG_IPV6)
44 int udp_sock_create6(struct net *net, struct udp_port_cfg *cfg,
45 		     struct socket **sockp);
46 #else
udp_sock_create6(struct net * net,struct udp_port_cfg * cfg,struct socket ** sockp)47 static inline int udp_sock_create6(struct net *net, struct udp_port_cfg *cfg,
48 				   struct socket **sockp)
49 {
50 	return 0;
51 }
52 #endif
53 
udp_sock_create(struct net * net,struct udp_port_cfg * cfg,struct socket ** sockp)54 static inline int udp_sock_create(struct net *net,
55 				  struct udp_port_cfg *cfg,
56 				  struct socket **sockp)
57 {
58 	if (cfg->family == AF_INET)
59 		return udp_sock_create4(net, cfg, sockp);
60 
61 	if (cfg->family == AF_INET6)
62 		return udp_sock_create6(net, cfg, sockp);
63 
64 	return -EPFNOSUPPORT;
65 }
66 
67 typedef int (*udp_tunnel_encap_rcv_t)(struct sock *sk, struct sk_buff *skb);
68 typedef int (*udp_tunnel_encap_err_lookup_t)(struct sock *sk,
69 					     struct sk_buff *skb);
70 typedef void (*udp_tunnel_encap_err_rcv_t)(struct sock *sk,
71 					   struct sk_buff *skb, int err,
72 					   __be16 port, u32 info, u8 *payload);
73 typedef void (*udp_tunnel_encap_destroy_t)(struct sock *sk);
74 typedef struct sk_buff *(*udp_tunnel_gro_receive_t)(struct sock *sk,
75 						    struct list_head *head,
76 						    struct sk_buff *skb);
77 typedef int (*udp_tunnel_gro_complete_t)(struct sock *sk, struct sk_buff *skb,
78 					 int nhoff);
79 
80 struct udp_tunnel_sock_cfg {
81 	void *sk_user_data;     /* user data used by encap_rcv call back */
82 	/* Used for setting up udp_sock fields, see udp.h for details */
83 	__u8  encap_type;
84 	udp_tunnel_encap_rcv_t encap_rcv;
85 	udp_tunnel_encap_err_lookup_t encap_err_lookup;
86 	udp_tunnel_encap_err_rcv_t encap_err_rcv;
87 	udp_tunnel_encap_destroy_t encap_destroy;
88 	udp_tunnel_gro_receive_t gro_receive;
89 	udp_tunnel_gro_complete_t gro_complete;
90 };
91 
92 /* Setup the given (UDP) sock to receive UDP encapsulated packets */
93 void setup_udp_tunnel_sock(struct net *net, struct socket *sock,
94 			   struct udp_tunnel_sock_cfg *sock_cfg);
95 
96 /* -- List of parsable UDP tunnel types --
97  *
98  * Adding to this list will result in serious debate.  The main issue is
99  * that this list is essentially a list of workarounds for either poorly
100  * designed tunnels, or poorly designed device offloads.
101  *
102  * The parsing supported via these types should really be used for Rx
103  * traffic only as the network stack will have already inserted offsets for
104  * the location of the headers in the skb.  In addition any ports that are
105  * pushed should be kept within the namespace without leaking to other
106  * devices such as VFs or other ports on the same device.
107  *
108  * It is strongly encouraged to use CHECKSUM_COMPLETE for Rx to avoid the
109  * need to use this for Rx checksum offload.  It should not be necessary to
110  * call this function to perform Tx offloads on outgoing traffic.
111  */
112 enum udp_parsable_tunnel_type {
113 	UDP_TUNNEL_TYPE_VXLAN	  = BIT(0), /* RFC 7348 */
114 	UDP_TUNNEL_TYPE_GENEVE	  = BIT(1), /* draft-ietf-nvo3-geneve */
115 	UDP_TUNNEL_TYPE_VXLAN_GPE = BIT(2), /* draft-ietf-nvo3-vxlan-gpe */
116 };
117 
118 struct udp_tunnel_info {
119 	unsigned short type;
120 	sa_family_t sa_family;
121 	__be16 port;
122 	u8 hw_priv;
123 };
124 
125 /* Notify network devices of offloadable types */
126 void udp_tunnel_push_rx_port(struct net_device *dev, struct socket *sock,
127 			     unsigned short type);
128 void udp_tunnel_drop_rx_port(struct net_device *dev, struct socket *sock,
129 			     unsigned short type);
130 void udp_tunnel_notify_add_rx_port(struct socket *sock, unsigned short type);
131 void udp_tunnel_notify_del_rx_port(struct socket *sock, unsigned short type);
132 
133 /* Transmit the skb using UDP encapsulation. */
134 void udp_tunnel_xmit_skb(struct rtable *rt, struct sock *sk, struct sk_buff *skb,
135 			 __be32 src, __be32 dst, __u8 tos, __u8 ttl,
136 			 __be16 df, __be16 src_port, __be16 dst_port,
137 			 bool xnet, bool nocheck, u16 ipcb_flags);
138 
139 void udp_tunnel6_xmit_skb(struct dst_entry *dst, struct sock *sk,
140 			  struct sk_buff *skb,
141 			  struct net_device *dev,
142 			  const struct in6_addr *saddr,
143 			  const struct in6_addr *daddr,
144 			  __u8 prio, __u8 ttl, __be32 label,
145 			  __be16 src_port, __be16 dst_port, bool nocheck,
146 			  u16 ip6cb_flags);
147 
148 void udp_tunnel_sock_release(struct socket *sock);
149 
150 struct rtable *udp_tunnel_dst_lookup(struct sk_buff *skb,
151 				     struct net_device *dev,
152 				     struct net *net, int oif,
153 				     __be32 *saddr,
154 				     const struct ip_tunnel_key *key,
155 				     __be16 sport, __be16 dport, u8 tos,
156 				     struct dst_cache *dst_cache);
157 struct dst_entry *udp_tunnel6_dst_lookup(struct sk_buff *skb,
158 					 struct net_device *dev,
159 					 struct net *net,
160 					 struct socket *sock, int oif,
161 					 struct in6_addr *saddr,
162 					 const struct ip_tunnel_key *key,
163 					 __be16 sport, __be16 dport, u8 dsfield,
164 					 struct dst_cache *dst_cache);
165 
166 struct metadata_dst *udp_tun_rx_dst(struct sk_buff *skb, unsigned short family,
167 				    const unsigned long *flags,
168 				    __be64 tunnel_id, int md_size);
169 
170 #ifdef CONFIG_INET
udp_tunnel_handle_offloads(struct sk_buff * skb,bool udp_csum)171 static inline int udp_tunnel_handle_offloads(struct sk_buff *skb, bool udp_csum)
172 {
173 	int type = udp_csum ? SKB_GSO_UDP_TUNNEL_CSUM : SKB_GSO_UDP_TUNNEL;
174 
175 	return iptunnel_handle_offloads(skb, type);
176 }
177 #endif
178 
179 #if IS_ENABLED(CONFIG_NET_UDP_TUNNEL)
180 void udp_tunnel_update_gro_lookup(struct net *net, struct sock *sk, bool add);
181 void udp_tunnel_update_gro_rcv(struct sock *sk, bool add);
182 #else
udp_tunnel_update_gro_lookup(struct net * net,struct sock * sk,bool add)183 static inline void udp_tunnel_update_gro_lookup(struct net *net,
184 						struct sock *sk, bool add) {}
udp_tunnel_update_gro_rcv(struct sock * sk,bool add)185 static inline void udp_tunnel_update_gro_rcv(struct sock *sk, bool add) {}
186 #endif
187 
udp_tunnel_cleanup_gro(struct sock * sk)188 static inline void udp_tunnel_cleanup_gro(struct sock *sk)
189 {
190 	udp_tunnel_update_gro_rcv(sk, false);
191 	udp_tunnel_update_gro_lookup(sock_net(sk), sk, false);
192 }
193 
udp_tunnel_encap_enable(struct sock * sk)194 static inline void udp_tunnel_encap_enable(struct sock *sk)
195 {
196 	if (udp_test_and_set_bit(ENCAP_ENABLED, sk))
197 		return;
198 
199 #if IS_ENABLED(CONFIG_IPV6)
200 	if (READ_ONCE(sk->sk_family) == PF_INET6)
201 		ipv6_stub->udpv6_encap_enable();
202 #endif
203 	udp_encap_enable();
204 }
205 
206 #define UDP_TUNNEL_NIC_MAX_TABLES	4
207 
208 enum udp_tunnel_nic_info_flags {
209 	/* Device only supports offloads when it's open, all ports
210 	 * will be removed before close and re-added after open.
211 	 */
212 	UDP_TUNNEL_NIC_INFO_OPEN_ONLY	= BIT(0),
213 	/* Device supports only IPv4 tunnels */
214 	UDP_TUNNEL_NIC_INFO_IPV4_ONLY	= BIT(1),
215 	/* Device has hard-coded the IANA VXLAN port (4789) as VXLAN.
216 	 * This port must not be counted towards n_entries of any table.
217 	 * Driver will not receive any callback associated with port 4789.
218 	 */
219 	UDP_TUNNEL_NIC_INFO_STATIC_IANA_VXLAN	= BIT(2),
220 };
221 
222 struct udp_tunnel_nic;
223 
224 #define UDP_TUNNEL_NIC_MAX_SHARING_DEVICES	(U16_MAX / 2)
225 
226 struct udp_tunnel_nic_shared {
227 	struct udp_tunnel_nic *udp_tunnel_nic_info;
228 
229 	struct list_head devices;
230 };
231 
232 struct udp_tunnel_nic_shared_node {
233 	struct net_device *dev;
234 	struct list_head list;
235 };
236 
237 /**
238  * struct udp_tunnel_nic_info - driver UDP tunnel offload information
239  * @set_port:	callback for adding a new port
240  * @unset_port:	callback for removing a port
241  * @sync_table:	callback for syncing the entire port table at once
242  * @shared:	reference to device global state (optional)
243  * @flags:	device flags from enum udp_tunnel_nic_info_flags
244  * @tables:	UDP port tables this device has
245  * @tables.n_entries:		number of entries in this table
246  * @tables.tunnel_types:	types of tunnels this table accepts
247  *
248  * Drivers are expected to provide either @set_port and @unset_port callbacks
249  * or the @sync_table callback. Callbacks are invoked with rtnl lock held.
250  *
251  * Devices which (misguidedly) share the UDP tunnel port table across multiple
252  * netdevs should allocate an instance of struct udp_tunnel_nic_shared and
253  * point @shared at it.
254  * There must never be more than %UDP_TUNNEL_NIC_MAX_SHARING_DEVICES devices
255  * sharing a table.
256  *
257  * Known limitations:
258  *  - UDP tunnel port notifications are fundamentally best-effort -
259  *    it is likely the driver will both see skbs which use a UDP tunnel port,
260  *    while not being a tunneled skb, and tunnel skbs from other ports -
261  *    drivers should only use these ports for non-critical RX-side offloads,
262  *    e.g. the checksum offload;
263  *  - none of the devices care about the socket family at present, so we don't
264  *    track it. Please extend this code if you care.
265  */
266 struct udp_tunnel_nic_info {
267 	/* one-by-one */
268 	int (*set_port)(struct net_device *dev,
269 			unsigned int table, unsigned int entry,
270 			struct udp_tunnel_info *ti);
271 	int (*unset_port)(struct net_device *dev,
272 			  unsigned int table, unsigned int entry,
273 			  struct udp_tunnel_info *ti);
274 
275 	/* all at once */
276 	int (*sync_table)(struct net_device *dev, unsigned int table);
277 
278 	struct udp_tunnel_nic_shared *shared;
279 
280 	unsigned int flags;
281 
282 	struct udp_tunnel_nic_table_info {
283 		unsigned int n_entries;
284 		unsigned int tunnel_types;
285 	} tables[UDP_TUNNEL_NIC_MAX_TABLES];
286 };
287 
288 /* UDP tunnel module dependencies
289  *
290  * Tunnel drivers are expected to have a hard dependency on the udp_tunnel
291  * module. NIC drivers are not, they just attach their
292  * struct udp_tunnel_nic_info to the netdev and wait for callbacks to come.
293  * Loading a tunnel driver will cause the udp_tunnel module to be loaded
294  * and only then will all the required state structures be allocated.
295  * Since we want a weak dependency from the drivers and the core to udp_tunnel
296  * we call things through the following stubs.
297  */
298 struct udp_tunnel_nic_ops {
299 	void (*get_port)(struct net_device *dev, unsigned int table,
300 			 unsigned int idx, struct udp_tunnel_info *ti);
301 	void (*set_port_priv)(struct net_device *dev, unsigned int table,
302 			      unsigned int idx, u8 priv);
303 	void (*add_port)(struct net_device *dev, struct udp_tunnel_info *ti);
304 	void (*del_port)(struct net_device *dev, struct udp_tunnel_info *ti);
305 	void (*reset_ntf)(struct net_device *dev);
306 
307 	size_t (*dump_size)(struct net_device *dev, unsigned int table);
308 	int (*dump_write)(struct net_device *dev, unsigned int table,
309 			  struct sk_buff *skb);
310 	void (*assert_locked)(struct net_device *dev);
311 	void (*lock)(struct net_device *dev);
312 	void (*unlock)(struct net_device *dev);
313 };
314 
315 #ifdef CONFIG_INET
316 extern const struct udp_tunnel_nic_ops *udp_tunnel_nic_ops;
317 #else
318 #define udp_tunnel_nic_ops	((struct udp_tunnel_nic_ops *)NULL)
319 #endif
320 
321 static inline void
udp_tunnel_nic_get_port(struct net_device * dev,unsigned int table,unsigned int idx,struct udp_tunnel_info * ti)322 udp_tunnel_nic_get_port(struct net_device *dev, unsigned int table,
323 			unsigned int idx, struct udp_tunnel_info *ti)
324 {
325 	/* This helper is used from .sync_table, we indicate empty entries
326 	 * by zero'ed @ti. Drivers which need to know the details of a port
327 	 * when it gets deleted should use the .set_port / .unset_port
328 	 * callbacks.
329 	 * Zero out here, otherwise !CONFIG_INET causes uninitilized warnings.
330 	 */
331 	memset(ti, 0, sizeof(*ti));
332 
333 	if (udp_tunnel_nic_ops)
334 		udp_tunnel_nic_ops->get_port(dev, table, idx, ti);
335 }
336 
337 static inline void
udp_tunnel_nic_set_port_priv(struct net_device * dev,unsigned int table,unsigned int idx,u8 priv)338 udp_tunnel_nic_set_port_priv(struct net_device *dev, unsigned int table,
339 			     unsigned int idx, u8 priv)
340 {
341 	if (udp_tunnel_nic_ops) {
342 		udp_tunnel_nic_ops->assert_locked(dev);
343 		udp_tunnel_nic_ops->set_port_priv(dev, table, idx, priv);
344 	}
345 }
346 
udp_tunnel_nic_assert_locked(struct net_device * dev)347 static inline void udp_tunnel_nic_assert_locked(struct net_device *dev)
348 {
349 	if (udp_tunnel_nic_ops)
350 		udp_tunnel_nic_ops->assert_locked(dev);
351 }
352 
udp_tunnel_nic_lock(struct net_device * dev)353 static inline void udp_tunnel_nic_lock(struct net_device *dev)
354 {
355 	if (udp_tunnel_nic_ops)
356 		udp_tunnel_nic_ops->lock(dev);
357 }
358 
udp_tunnel_nic_unlock(struct net_device * dev)359 static inline void udp_tunnel_nic_unlock(struct net_device *dev)
360 {
361 	if (udp_tunnel_nic_ops)
362 		udp_tunnel_nic_ops->unlock(dev);
363 }
364 
365 static inline void
udp_tunnel_nic_add_port(struct net_device * dev,struct udp_tunnel_info * ti)366 udp_tunnel_nic_add_port(struct net_device *dev, struct udp_tunnel_info *ti)
367 {
368 	if (!(dev->features & NETIF_F_RX_UDP_TUNNEL_PORT))
369 		return;
370 	if (udp_tunnel_nic_ops)
371 		udp_tunnel_nic_ops->add_port(dev, ti);
372 }
373 
374 static inline void
udp_tunnel_nic_del_port(struct net_device * dev,struct udp_tunnel_info * ti)375 udp_tunnel_nic_del_port(struct net_device *dev, struct udp_tunnel_info *ti)
376 {
377 	if (!(dev->features & NETIF_F_RX_UDP_TUNNEL_PORT))
378 		return;
379 	if (udp_tunnel_nic_ops)
380 		udp_tunnel_nic_ops->del_port(dev, ti);
381 }
382 
383 /**
384  * udp_tunnel_nic_reset_ntf() - device-originating reset notification
385  * @dev: network interface device structure
386  *
387  * Called by the driver to inform the core that the entire UDP tunnel port
388  * state has been lost, usually due to device reset. Core will assume device
389  * forgot all the ports and issue .set_port and .sync_table callbacks as
390  * necessary.
391  *
392  * This function must be called with rtnl lock held, and will issue all
393  * the callbacks before returning.
394  */
udp_tunnel_nic_reset_ntf(struct net_device * dev)395 static inline void udp_tunnel_nic_reset_ntf(struct net_device *dev)
396 {
397 	if (udp_tunnel_nic_ops)
398 		udp_tunnel_nic_ops->reset_ntf(dev);
399 }
400 
401 static inline size_t
udp_tunnel_nic_dump_size(struct net_device * dev,unsigned int table)402 udp_tunnel_nic_dump_size(struct net_device *dev, unsigned int table)
403 {
404 	size_t ret;
405 
406 	if (!udp_tunnel_nic_ops)
407 		return 0;
408 
409 	udp_tunnel_nic_ops->lock(dev);
410 	ret = udp_tunnel_nic_ops->dump_size(dev, table);
411 	udp_tunnel_nic_ops->unlock(dev);
412 
413 	return ret;
414 }
415 
416 static inline int
udp_tunnel_nic_dump_write(struct net_device * dev,unsigned int table,struct sk_buff * skb)417 udp_tunnel_nic_dump_write(struct net_device *dev, unsigned int table,
418 			  struct sk_buff *skb)
419 {
420 	int ret;
421 
422 	if (!udp_tunnel_nic_ops)
423 		return 0;
424 
425 	udp_tunnel_nic_ops->lock(dev);
426 	ret = udp_tunnel_nic_ops->dump_write(dev, table, skb);
427 	udp_tunnel_nic_ops->unlock(dev);
428 
429 	return ret;
430 }
431 
udp_tunnel_get_rx_info(struct net_device * dev)432 static inline void udp_tunnel_get_rx_info(struct net_device *dev)
433 {
434 	ASSERT_RTNL();
435 	if (!(dev->features & NETIF_F_RX_UDP_TUNNEL_PORT))
436 		return;
437 	udp_tunnel_nic_assert_locked(dev);
438 	call_netdevice_notifiers(NETDEV_UDP_TUNNEL_PUSH_INFO, dev);
439 }
440 
udp_tunnel_drop_rx_info(struct net_device * dev)441 static inline void udp_tunnel_drop_rx_info(struct net_device *dev)
442 {
443 	ASSERT_RTNL();
444 	if (!(dev->features & NETIF_F_RX_UDP_TUNNEL_PORT))
445 		return;
446 	udp_tunnel_nic_assert_locked(dev);
447 	call_netdevice_notifiers(NETDEV_UDP_TUNNEL_DROP_INFO, dev);
448 }
449 
450 #endif
451