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
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
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 static inline void udp_tunnel_get_rx_info(struct net_device *dev)
134 {
135 ASSERT_RTNL();
136 if (!(dev->features & NETIF_F_RX_UDP_TUNNEL_PORT))
137 return;
138 call_netdevice_notifiers(NETDEV_UDP_TUNNEL_PUSH_INFO, dev);
139 }
140
141 static inline void udp_tunnel_drop_rx_info(struct net_device *dev)
142 {
143 ASSERT_RTNL();
144 if (!(dev->features & NETIF_F_RX_UDP_TUNNEL_PORT))
145 return;
146 call_netdevice_notifiers(NETDEV_UDP_TUNNEL_DROP_INFO, dev);
147 }
148
149 /* Transmit the skb using UDP encapsulation. */
150 void udp_tunnel_xmit_skb(struct rtable *rt, struct sock *sk, struct sk_buff *skb,
151 __be32 src, __be32 dst, __u8 tos, __u8 ttl,
152 __be16 df, __be16 src_port, __be16 dst_port,
153 bool xnet, bool nocheck);
154
155 int udp_tunnel6_xmit_skb(struct dst_entry *dst, struct sock *sk,
156 struct sk_buff *skb,
157 struct net_device *dev,
158 const struct in6_addr *saddr,
159 const struct in6_addr *daddr,
160 __u8 prio, __u8 ttl, __be32 label,
161 __be16 src_port, __be16 dst_port, bool nocheck);
162
163 void udp_tunnel_sock_release(struct socket *sock);
164
165 struct rtable *udp_tunnel_dst_lookup(struct sk_buff *skb,
166 struct net_device *dev,
167 struct net *net, int oif,
168 __be32 *saddr,
169 const struct ip_tunnel_key *key,
170 __be16 sport, __be16 dport, u8 tos,
171 struct dst_cache *dst_cache);
172 struct dst_entry *udp_tunnel6_dst_lookup(struct sk_buff *skb,
173 struct net_device *dev,
174 struct net *net,
175 struct socket *sock, int oif,
176 struct in6_addr *saddr,
177 const struct ip_tunnel_key *key,
178 __be16 sport, __be16 dport, u8 dsfield,
179 struct dst_cache *dst_cache);
180
181 struct metadata_dst *udp_tun_rx_dst(struct sk_buff *skb, unsigned short family,
182 const unsigned long *flags,
183 __be64 tunnel_id, int md_size);
184
185 #ifdef CONFIG_INET
186 static inline int udp_tunnel_handle_offloads(struct sk_buff *skb, bool udp_csum)
187 {
188 int type = udp_csum ? SKB_GSO_UDP_TUNNEL_CSUM : SKB_GSO_UDP_TUNNEL;
189
190 return iptunnel_handle_offloads(skb, type);
191 }
192 #endif
193
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 callbacks may sleep */
210 UDP_TUNNEL_NIC_INFO_MAY_SLEEP = BIT(0),
211 /* Device only supports offloads when it's open, all ports
212 * will be removed before close and re-added after open.
213 */
214 UDP_TUNNEL_NIC_INFO_OPEN_ONLY = BIT(1),
215 /* Device supports only IPv4 tunnels */
216 UDP_TUNNEL_NIC_INFO_IPV4_ONLY = BIT(2),
217 /* Device has hard-coded the IANA VXLAN port (4789) as VXLAN.
218 * This port must not be counted towards n_entries of any table.
219 * Driver will not receive any callback associated with port 4789.
220 */
221 UDP_TUNNEL_NIC_INFO_STATIC_IANA_VXLAN = BIT(3),
222 };
223
224 struct udp_tunnel_nic;
225
226 #define UDP_TUNNEL_NIC_MAX_SHARING_DEVICES (U16_MAX / 2)
227
228 struct udp_tunnel_nic_shared {
229 struct udp_tunnel_nic *udp_tunnel_nic_info;
230
231 struct list_head devices;
232 };
233
234 struct udp_tunnel_nic_shared_node {
235 struct net_device *dev;
236 struct list_head list;
237 };
238
239 /**
240 * struct udp_tunnel_nic_info - driver UDP tunnel offload information
241 * @set_port: callback for adding a new port
242 * @unset_port: callback for removing a port
243 * @sync_table: callback for syncing the entire port table at once
244 * @shared: reference to device global state (optional)
245 * @flags: device flags from enum udp_tunnel_nic_info_flags
246 * @tables: UDP port tables this device has
247 * @tables.n_entries: number of entries in this table
248 * @tables.tunnel_types: types of tunnels this table accepts
249 *
250 * Drivers are expected to provide either @set_port and @unset_port callbacks
251 * or the @sync_table callback. Callbacks are invoked with rtnl lock held.
252 *
253 * Devices which (misguidedly) share the UDP tunnel port table across multiple
254 * netdevs should allocate an instance of struct udp_tunnel_nic_shared and
255 * point @shared at it.
256 * There must never be more than %UDP_TUNNEL_NIC_MAX_SHARING_DEVICES devices
257 * sharing a table.
258 *
259 * Known limitations:
260 * - UDP tunnel port notifications are fundamentally best-effort -
261 * it is likely the driver will both see skbs which use a UDP tunnel port,
262 * while not being a tunneled skb, and tunnel skbs from other ports -
263 * drivers should only use these ports for non-critical RX-side offloads,
264 * e.g. the checksum offload;
265 * - none of the devices care about the socket family at present, so we don't
266 * track it. Please extend this code if you care.
267 */
268 struct udp_tunnel_nic_info {
269 /* one-by-one */
270 int (*set_port)(struct net_device *dev,
271 unsigned int table, unsigned int entry,
272 struct udp_tunnel_info *ti);
273 int (*unset_port)(struct net_device *dev,
274 unsigned int table, unsigned int entry,
275 struct udp_tunnel_info *ti);
276
277 /* all at once */
278 int (*sync_table)(struct net_device *dev, unsigned int table);
279
280 struct udp_tunnel_nic_shared *shared;
281
282 unsigned int flags;
283
284 struct udp_tunnel_nic_table_info {
285 unsigned int n_entries;
286 unsigned int tunnel_types;
287 } tables[UDP_TUNNEL_NIC_MAX_TABLES];
288 };
289
290 /* UDP tunnel module dependencies
291 *
292 * Tunnel drivers are expected to have a hard dependency on the udp_tunnel
293 * module. NIC drivers are not, they just attach their
294 * struct udp_tunnel_nic_info to the netdev and wait for callbacks to come.
295 * Loading a tunnel driver will cause the udp_tunnel module to be loaded
296 * and only then will all the required state structures be allocated.
297 * Since we want a weak dependency from the drivers and the core to udp_tunnel
298 * we call things through the following stubs.
299 */
300 struct udp_tunnel_nic_ops {
301 void (*get_port)(struct net_device *dev, unsigned int table,
302 unsigned int idx, struct udp_tunnel_info *ti);
303 void (*set_port_priv)(struct net_device *dev, unsigned int table,
304 unsigned int idx, u8 priv);
305 void (*add_port)(struct net_device *dev, struct udp_tunnel_info *ti);
306 void (*del_port)(struct net_device *dev, struct udp_tunnel_info *ti);
307 void (*reset_ntf)(struct net_device *dev);
308
309 size_t (*dump_size)(struct net_device *dev, unsigned int table);
310 int (*dump_write)(struct net_device *dev, unsigned int table,
311 struct sk_buff *skb);
312 };
313
314 #ifdef CONFIG_INET
315 extern const struct udp_tunnel_nic_ops *udp_tunnel_nic_ops;
316 #else
317 #define udp_tunnel_nic_ops ((struct udp_tunnel_nic_ops *)NULL)
318 #endif
319
320 static inline void
321 udp_tunnel_nic_get_port(struct net_device *dev, unsigned int table,
322 unsigned int idx, struct udp_tunnel_info *ti)
323 {
324 /* This helper is used from .sync_table, we indicate empty entries
325 * by zero'ed @ti. Drivers which need to know the details of a port
326 * when it gets deleted should use the .set_port / .unset_port
327 * callbacks.
328 * Zero out here, otherwise !CONFIG_INET causes uninitilized warnings.
329 */
330 memset(ti, 0, sizeof(*ti));
331
332 if (udp_tunnel_nic_ops)
333 udp_tunnel_nic_ops->get_port(dev, table, idx, ti);
334 }
335
336 static inline void
337 udp_tunnel_nic_set_port_priv(struct net_device *dev, unsigned int table,
338 unsigned int idx, u8 priv)
339 {
340 if (udp_tunnel_nic_ops)
341 udp_tunnel_nic_ops->set_port_priv(dev, table, idx, priv);
342 }
343
344 static inline void
345 udp_tunnel_nic_add_port(struct net_device *dev, struct udp_tunnel_info *ti)
346 {
347 if (!(dev->features & NETIF_F_RX_UDP_TUNNEL_PORT))
348 return;
349 if (udp_tunnel_nic_ops)
350 udp_tunnel_nic_ops->add_port(dev, ti);
351 }
352
353 static inline void
354 udp_tunnel_nic_del_port(struct net_device *dev, struct udp_tunnel_info *ti)
355 {
356 if (!(dev->features & NETIF_F_RX_UDP_TUNNEL_PORT))
357 return;
358 if (udp_tunnel_nic_ops)
359 udp_tunnel_nic_ops->del_port(dev, ti);
360 }
361
362 /**
363 * udp_tunnel_nic_reset_ntf() - device-originating reset notification
364 * @dev: network interface device structure
365 *
366 * Called by the driver to inform the core that the entire UDP tunnel port
367 * state has been lost, usually due to device reset. Core will assume device
368 * forgot all the ports and issue .set_port and .sync_table callbacks as
369 * necessary.
370 *
371 * This function must be called with rtnl lock held, and will issue all
372 * the callbacks before returning.
373 */
374 static inline void udp_tunnel_nic_reset_ntf(struct net_device *dev)
375 {
376 if (udp_tunnel_nic_ops)
377 udp_tunnel_nic_ops->reset_ntf(dev);
378 }
379
380 static inline size_t
381 udp_tunnel_nic_dump_size(struct net_device *dev, unsigned int table)
382 {
383 if (!udp_tunnel_nic_ops)
384 return 0;
385 return udp_tunnel_nic_ops->dump_size(dev, table);
386 }
387
388 static inline int
389 udp_tunnel_nic_dump_write(struct net_device *dev, unsigned int table,
390 struct sk_buff *skb)
391 {
392 if (!udp_tunnel_nic_ops)
393 return 0;
394 return udp_tunnel_nic_ops->dump_write(dev, table, skb);
395 }
396 #endif
397
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